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[GNUnet-SVN] r27499 - gnunet/src/regex
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From: |
gnunet |
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Subject: |
[GNUnet-SVN] r27499 - gnunet/src/regex |
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Date: |
Thu, 20 Jun 2013 10:55:56 +0200 |
Author: grothoff
Date: 2013-06-20 10:55:56 +0200 (Thu, 20 Jun 2013)
New Revision: 27499
Added:
gnunet/src/regex/regex_internal.c
gnunet/src/regex/regex_internal_dht.c
gnunet/src/regex/regex_test_graph.c
gnunet/src/regex/regex_test_random.c
Removed:
gnunet/src/regex/regex.c
gnunet/src/regex/regex_dht.c
gnunet/src/regex/regex_graph.c
gnunet/src/regex/regex_random.c
Modified:
gnunet/src/regex/Makefile.am
gnunet/src/regex/regex_internal.h
gnunet/src/regex/regex_internal_lib.h
gnunet/src/regex/regex_test_lib.h
gnunet/src/regex/test_regex_eval_api.c
gnunet/src/regex/test_regex_graph_api.c
gnunet/src/regex/test_regex_proofs.c
Log:
moving functions for testing and evaluation and experiments to the test
library, minimizing the internal library, renaming files according to which
library they belong to
Modified: gnunet/src/regex/Makefile.am
===================================================================
--- gnunet/src/regex/Makefile.am 2013-06-20 08:32:50 UTC (rev 27498)
+++ gnunet/src/regex/Makefile.am 2013-06-20 08:55:56 UTC (rev 27499)
@@ -55,9 +55,9 @@
libgnunetregex_internal_a_SOURCES = \
- regex_internal.h regex.c \
- regex_graph.c regex_random.c \
- regex_dht.c
+ regex_internal_lib.h \
+ regex_internal.h regex_internal.c \
+ regex_internal_dht.c
libgnunetregex_internal_a_DEPENDENCIES = \
libgnunetregexblock.la
@@ -100,7 +100,9 @@
endif
libgnunetregextest_a_SOURCES = \
- regex_test_lib.c regex_test_lib.h
+ regex_test_lib.c regex_test_lib.h \
+ regex_test_graph.c \
+ regex_test_random.c
libgnunetregextest_a_LIBADD = \
$(top_builddir)/src/util/libgnunetutil.la \
$(top_builddir)/src/regex/libgnunetregex_internal.a
@@ -172,6 +174,7 @@
test_regex_eval_api.c
test_regex_eval_api_LDADD = -lm \
$(top_builddir)/src/regex/libgnunetregex_internal.a \
+ $(top_builddir)/src/regex/libgnunetregextest.a \
$(top_builddir)/src/regex/libgnunetregexblock.la \
$(top_builddir)/src/util/libgnunetutil.la
@@ -186,6 +189,7 @@
test_regex_proofs.c
test_regex_proofs_LDADD = -lm \
$(top_builddir)/src/regex/libgnunetregex_internal.a \
+ $(top_builddir)/src/regex/libgnunetregextest.a \
$(top_builddir)/src/regex/libgnunetregexblock.la \
$(top_builddir)/src/util/libgnunetutil.la
@@ -193,6 +197,7 @@
test_regex_graph_api.c
test_regex_graph_api_LDADD = -lm \
$(top_builddir)/src/regex/libgnunetregex_internal.a \
+ $(top_builddir)/src/regex/libgnunetregextest.a \
$(top_builddir)/src/regex/libgnunetregexblock.la \
$(top_builddir)/src/util/libgnunetutil.la
Deleted: gnunet/src/regex/regex.c
===================================================================
--- gnunet/src/regex/regex.c 2013-06-20 08:32:50 UTC (rev 27498)
+++ gnunet/src/regex/regex.c 2013-06-20 08:55:56 UTC (rev 27499)
@@ -1,3485 +0,0 @@
-/*
- This file is part of GNUnet
- (C) 2012 Christian Grothoff (and other contributing authors)
-
- GNUnet is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published
- by the Free Software Foundation; either version 3, or (at your
- option) any later version.
-
- GNUnet is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with GNUnet; see the file COPYING. If not, write to the
- Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA.
-*/
-/**
- * @file src/regex/regex.c
- * @brief library to create Deterministic Finite Automatons (DFAs) from regular
- * expressions (regexes).
- * @author Maximilian Szengel
- */
-#include "platform.h"
-#include "gnunet_util_lib.h"
-#include "gnunet_regex_service.h"
-#include "regex_internal_lib.h"
-#include "regex_internal.h"
-
-
-/**
- * Set this to GNUNET_YES to enable state naming. Used to debug NFA->DFA
- * creation. Disabled by default for better performance.
- */
-#define REGEX_DEBUG_DFA GNUNET_NO
-
-/**
- * Set of states using MDLL API.
- */
-struct REGEX_ITERNAL_StateSet_MDLL
-{
- /**
- * MDLL of states.
- */
- struct REGEX_ITERNAL_State *head;
-
- /**
- * MDLL of states.
- */
- struct REGEX_ITERNAL_State *tail;
-
- /**
- * Length of the MDLL.
- */
- unsigned int len;
-};
-
-
-/**
- * Append state to the given StateSet '
- *
- * @param set set to be modified
- * @param state state to be appended
- */
-static void
-state_set_append (struct REGEX_ITERNAL_StateSet *set,
- struct REGEX_ITERNAL_State *state)
-{
- if (set->off == set->size)
- GNUNET_array_grow (set->states, set->size, set->size * 2 + 4);
- set->states[set->off++] = state;
-}
-
-
-/**
- * Compare two strings for equality. If either is NULL they are not equal.
- *
- * @param str1 first string for comparison.
- * @param str2 second string for comparison.
- *
- * @return 0 if the strings are the same or both NULL, 1 or -1 if not.
- */
-static int
-nullstrcmp (const char *str1, const char *str2)
-{
- if ((NULL == str1) != (NULL == str2))
- return -1;
- if ((NULL == str1) && (NULL == str2))
- return 0;
-
- return strcmp (str1, str2);
-}
-
-
-/**
- * Adds a transition from one state to another on 'label'. Does not add
- * duplicate states.
- *
- * @param ctx context
- * @param from_state starting state for the transition
- * @param label transition label
- * @param to_state state to where the transition should point to
- */
-static void
-state_add_transition (struct REGEX_ITERNAL_Context *ctx,
- struct REGEX_ITERNAL_State *from_state, const char
*label,
- struct REGEX_ITERNAL_State *to_state)
-{
- struct REGEX_ITERNAL_Transition *t;
- struct REGEX_ITERNAL_Transition *oth;
-
- if (NULL == from_state)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Could not create Transition.\n");
- return;
- }
-
- /* Do not add duplicate state transitions */
- for (t = from_state->transitions_head; NULL != t; t = t->next)
- {
- if (t->to_state == to_state && 0 == nullstrcmp (t->label, label) &&
- t->from_state == from_state)
- return;
- }
-
- /* sort transitions by label */
- for (oth = from_state->transitions_head; NULL != oth; oth = oth->next)
- {
- if (0 < nullstrcmp (oth->label, label))
- break;
- }
-
- t = GNUNET_malloc (sizeof (struct REGEX_ITERNAL_Transition));
- if (NULL != ctx)
- t->id = ctx->transition_id++;
- if (NULL != label)
- t->label = GNUNET_strdup (label);
- else
- t->label = NULL;
- t->to_state = to_state;
- t->from_state = from_state;
-
- /* Add outgoing transition to 'from_state' */
- from_state->transition_count++;
- GNUNET_CONTAINER_DLL_insert_before (from_state->transitions_head,
- from_state->transitions_tail, oth, t);
-}
-
-
-/**
- * Remove a 'transition' from 'state'.
- *
- * @param state state from which the to-be-removed transition originates.
- * @param transition transition that should be removed from state 'state'.
- */
-static void
-state_remove_transition (struct REGEX_ITERNAL_State *state,
- struct REGEX_ITERNAL_Transition *transition)
-{
- if (NULL == state || NULL == transition)
- return;
-
- if (transition->from_state != state)
- return;
-
- GNUNET_free_non_null (transition->label);
-
- state->transition_count--;
- GNUNET_CONTAINER_DLL_remove (state->transitions_head,
state->transitions_tail,
- transition);
-
- GNUNET_free (transition);
-}
-
-
-/**
- * Compare two states. Used for sorting.
- *
- * @param a first state
- * @param b second state
- *
- * @return an integer less than, equal to, or greater than zero
- * if the first argument is considered to be respectively
- * less than, equal to, or greater than the second.
- */
-static int
-state_compare (const void *a, const void *b)
-{
- struct REGEX_ITERNAL_State **s1 = (struct REGEX_ITERNAL_State **) a;
- struct REGEX_ITERNAL_State **s2 = (struct REGEX_ITERNAL_State **) b;
-
- return (*s1)->id - (*s2)->id;
-}
-
-
-/**
- * Get all edges leaving state 's'.
- *
- * @param s state.
- * @param edges all edges leaving 's', expected to be allocated and have enough
- * space for s->transitions_count elements.
- *
- * @return number of edges.
- */
-static unsigned int
-state_get_edges (struct REGEX_ITERNAL_State *s, struct REGEX_ITERNAL_Edge
*edges)
-{
- struct REGEX_ITERNAL_Transition *t;
- unsigned int count;
-
- if (NULL == s)
- return 0;
-
- count = 0;
-
- for (t = s->transitions_head; NULL != t; t = t->next)
- {
- if (NULL != t->to_state)
- {
- edges[count].label = t->label;
- edges[count].destination = t->to_state->hash;
- count++;
- }
- }
- return count;
-}
-
-
-/**
- * Compare to state sets by comparing the id's of the states that are contained
- * in each set. Both sets are expected to be sorted by id!
- *
- * @param sset1 first state set
- * @param sset2 second state set
- * @return 0 if the sets are equal, otherwise non-zero
- */
-static int
-state_set_compare (struct REGEX_ITERNAL_StateSet *sset1,
- struct REGEX_ITERNAL_StateSet *sset2)
-{
- int result;
- unsigned int i;
-
- if (NULL == sset1 || NULL == sset2)
- return 1;
-
- result = sset1->off - sset2->off;
- if (result < 0)
- return -1;
- if (result > 0)
- return 1;
- for (i = 0; i < sset1->off; i++)
- if (0 != (result = state_compare (&sset1->states[i], &sset2->states[i])))
- break;
- return result;
-}
-
-
-/**
- * Clears the given StateSet 'set'
- *
- * @param set set to be cleared
- */
-static void
-state_set_clear (struct REGEX_ITERNAL_StateSet *set)
-{
- GNUNET_array_grow (set->states, set->size, 0);
- set->off = 0;
-}
-
-
-/**
- * Clears an automaton fragment. Does not destroy the states inside the
- * automaton.
- *
- * @param a automaton to be cleared
- */
-static void
-automaton_fragment_clear (struct REGEX_ITERNAL_Automaton *a)
-{
- if (NULL == a)
- return;
-
- a->start = NULL;
- a->end = NULL;
- a->states_head = NULL;
- a->states_tail = NULL;
- a->state_count = 0;
- GNUNET_free (a);
-}
-
-
-/**
- * Frees the memory used by State 's'
- *
- * @param s state that should be destroyed
- */
-static void
-automaton_destroy_state (struct REGEX_ITERNAL_State *s)
-{
- struct REGEX_ITERNAL_Transition *t;
- struct REGEX_ITERNAL_Transition *next_t;
-
- if (NULL == s)
- return;
-
- GNUNET_free_non_null (s->name);
- GNUNET_free_non_null (s->proof);
- state_set_clear (&s->nfa_set);
- for (t = s->transitions_head; NULL != t; t = next_t)
- {
- next_t = t->next;
- state_remove_transition (s, t);
- }
-
- GNUNET_free (s);
-}
-
-
-/**
- * Remove a state from the given automaton 'a'. Always use this function when
- * altering the states of an automaton. Will also remove all transitions
leading
- * to this state, before destroying it.
- *
- * @param a automaton
- * @param s state to remove
- */
-static void
-automaton_remove_state (struct REGEX_ITERNAL_Automaton *a,
- struct REGEX_ITERNAL_State *s)
-{
- struct REGEX_ITERNAL_State *s_check;
- struct REGEX_ITERNAL_Transition *t_check;
- struct REGEX_ITERNAL_Transition *t_check_next;
-
- if (NULL == a || NULL == s)
- return;
-
- /* remove all transitions leading to this state */
- for (s_check = a->states_head; NULL != s_check; s_check = s_check->next)
- {
- for (t_check = s_check->transitions_head; NULL != t_check;
- t_check = t_check_next)
- {
- t_check_next = t_check->next;
- if (t_check->to_state == s)
- state_remove_transition (s_check, t_check);
- }
- }
-
- /* remove state */
- GNUNET_CONTAINER_DLL_remove (a->states_head, a->states_tail, s);
- a->state_count--;
-
- automaton_destroy_state (s);
-}
-
-
-/**
- * Merge two states into one. Will merge 's1' and 's2' into 's1' and destroy
- * 's2'. 's1' will contain all (non-duplicate) outgoing transitions of 's2'.
- *
- * @param ctx context
- * @param a automaton
- * @param s1 first state
- * @param s2 second state, will be destroyed
- */
-static void
-automaton_merge_states (struct REGEX_ITERNAL_Context *ctx,
- struct REGEX_ITERNAL_Automaton *a,
- struct REGEX_ITERNAL_State *s1,
- struct REGEX_ITERNAL_State *s2)
-{
- struct REGEX_ITERNAL_State *s_check;
- struct REGEX_ITERNAL_Transition *t_check;
- struct REGEX_ITERNAL_Transition *t;
- struct REGEX_ITERNAL_Transition *t_next;
- int is_dup;
-
- if (s1 == s2)
- return;
-
- /* 1. Make all transitions pointing to s2 point to s1, unless this transition
- * does not already exists, if it already exists remove transition. */
- for (s_check = a->states_head; NULL != s_check; s_check = s_check->next)
- {
- for (t_check = s_check->transitions_head; NULL != t_check; t_check =
t_next)
- {
- t_next = t_check->next;
-
- if (s2 == t_check->to_state)
- {
- is_dup = GNUNET_NO;
- for (t = t_check->from_state->transitions_head; NULL != t; t = t->next)
- {
- if (t->to_state == s1 && 0 == strcmp (t_check->label, t->label))
- is_dup = GNUNET_YES;
- }
- if (GNUNET_NO == is_dup)
- t_check->to_state = s1;
- else
- state_remove_transition (t_check->from_state, t_check);
- }
- }
- }
-
- /* 2. Add all transitions from s2 to sX to s1 */
- for (t_check = s2->transitions_head; NULL != t_check; t_check =
t_check->next)
- {
- if (t_check->to_state != s1)
- state_add_transition (ctx, s1, t_check->label, t_check->to_state);
- }
-
- /* 3. Rename s1 to {s1,s2} */
-#if REGEX_DEBUG_DFA
- char *new_name;
-
- new_name = s1->name;
- GNUNET_asprintf (&s1->name, "{%s,%s}", new_name, s2->name);
- GNUNET_free (new_name);
-#endif
-
- /* remove state */
- GNUNET_CONTAINER_DLL_remove (a->states_head, a->states_tail, s2);
- a->state_count--;
- automaton_destroy_state (s2);
-}
-
-
-/**
- * Add a state to the automaton 'a', always use this function to alter the
- * states DLL of the automaton.
- *
- * @param a automaton to add the state to
- * @param s state that should be added
- */
-static void
-automaton_add_state (struct REGEX_ITERNAL_Automaton *a,
- struct REGEX_ITERNAL_State *s)
-{
- GNUNET_CONTAINER_DLL_insert (a->states_head, a->states_tail, s);
- a->state_count++;
-}
-
-
-/**
- * Depth-first traversal (DFS) of all states that are reachable from state
- * 's'. Performs 'action' on each visited state.
- *
- * @param s start state.
- * @param marks an array of size a->state_count to remember which state was
- * already visited.
- * @param count current count of the state.
- * @param check function that is checked before advancing on each transition
- * in the DFS.
- * @param check_cls closure for check.
- * @param action action to be performed on each state.
- * @param action_cls closure for action.
- */
-static void
-automaton_state_traverse (struct REGEX_ITERNAL_State *s, int *marks,
- unsigned int *count,
- REGEX_ITERNAL_traverse_check check, void *check_cls,
- REGEX_ITERNAL_traverse_action action, void
*action_cls)
-{
- struct REGEX_ITERNAL_Transition *t;
-
- if (GNUNET_YES == marks[s->traversal_id])
- return;
-
- marks[s->traversal_id] = GNUNET_YES;
-
- if (NULL != action)
- action (action_cls, *count, s);
-
- (*count)++;
-
- for (t = s->transitions_head; NULL != t; t = t->next)
- {
- if (NULL == check ||
- (NULL != check && GNUNET_YES == check (check_cls, s, t)))
- {
- automaton_state_traverse (t->to_state, marks, count, check, check_cls,
- action, action_cls);
- }
- }
-}
-
-
-/**
- * Traverses the given automaton using depth-first-search (DFS) from it's start
- * state, visiting all reachable states and calling 'action' on each one of
- * them.
- *
- * @param a automaton to be traversed.
- * @param start start state, pass a->start or NULL to traverse the whole
automaton.
- * @param check function that is checked before advancing on each transition
- * in the DFS.
- * @param check_cls closure for check.
- * @param action action to be performed on each state.
- * @param action_cls closure for action
- */
-void
-REGEX_ITERNAL_automaton_traverse (const struct REGEX_ITERNAL_Automaton *a,
- struct REGEX_ITERNAL_State *start,
- REGEX_ITERNAL_traverse_check check,
- void *check_cls,
- REGEX_ITERNAL_traverse_action action,
- void *action_cls)
-{
- unsigned int count;
- struct REGEX_ITERNAL_State *s;
-
- if (NULL == a || 0 == a->state_count)
- return;
-
- int marks[a->state_count];
-
- for (count = 0, s = a->states_head; NULL != s && count < a->state_count;
- s = s->next, count++)
- {
- s->traversal_id = count;
- marks[s->traversal_id] = GNUNET_NO;
- }
-
- count = 0;
-
- if (NULL == start)
- s = a->start;
- else
- s = start;
-
- automaton_state_traverse (s, marks, &count, check, check_cls, action,
- action_cls);
-}
-
-
-/**
- * String container for faster string operations.
- */
-struct StringBuffer
-{
- /**
- * Buffer holding the string (may start in the middle!);
- * NOT 0-terminated!
- */
- char *sbuf;
-
- /**
- * Allocated buffer.
- */
- char *abuf;
-
- /**
- * Length of the string in the buffer.
- */
- size_t slen;
-
- /**
- * Number of bytes allocated for 'sbuf'
- */
- unsigned int blen;
-
- /**
- * Buffer currently represents "NULL" (not the empty string!)
- */
- int16_t null_flag;
-
- /**
- * If this entry is part of the last/current generation array,
- * this flag is GNUNET_YES if the last and current generation are
- * identical (and thus copying is unnecessary if the value didn't
- * change). This is used in an optimization that improves
- * performance by about 1% --- if we use int16_t here. With just
- * "int" for both flags, performance drops (on my system) significantly,
- * most likely due to increased cache misses.
- */
- int16_t synced;
-
-};
-
-
-/**
- * Compare two strings for equality. If either is NULL they are not equal.
- *
- * @param s1 first string for comparison.
- * @param s2 second string for comparison.
- *
- * @return 0 if the strings are the same or both NULL, 1 or -1 if not.
- */
-static int
-sb_nullstrcmp (const struct StringBuffer *s1,
- const struct StringBuffer *s2)
-{
- if ( (GNUNET_YES == s1->null_flag) &&
- (GNUNET_YES == s2->null_flag) )
- return 0;
- if ( (GNUNET_YES == s1->null_flag) ||
- (GNUNET_YES == s2->null_flag) )
- return -1;
- if (s1->slen != s2->slen)
- return -1;
- return memcmp (s1->sbuf, s2->sbuf, s1->slen);
-}
-
-
-/**
- * Compare two strings for equality.
- *
- * @param s1 first string for comparison.
- * @param s2 second string for comparison.
- *
- * @return 0 if the strings are the same, 1 or -1 if not.
- */
-static int
-sb_strcmp (const struct StringBuffer *s1,
- const struct StringBuffer *s2)
-{
- if (s1->slen != s2->slen)
- return -1;
- return memcmp (s1->sbuf, s2->sbuf, s1->slen);
-}
-
-
-/**
- * Reallocate the buffer of 'ret' to fit 'nlen' characters;
- * move the existing string to the beginning of the new buffer.
- *
- * @param ret current buffer, to be updated
- * @param nlen target length for the buffer, must be at least ret->slen
- */
-static void
-sb_realloc (struct StringBuffer *ret,
- size_t nlen)
-{
- char *old;
-
- GNUNET_assert (nlen >= ret->slen);
- old = ret->abuf;
- ret->abuf = GNUNET_malloc (nlen);
- ret->blen = nlen;
- memcpy (ret->abuf,
- ret->sbuf,
- ret->slen);
- ret->sbuf = ret->abuf;
- GNUNET_free_non_null (old);
-}
-
-
-/**
- * Append a string.
- *
- * @param ret where to write the result
- * @param sarg string to append
- */
-static void
-sb_append (struct StringBuffer *ret,
- const struct StringBuffer *sarg)
-{
- if (GNUNET_YES == ret->null_flag)
- ret->slen = 0;
- ret->null_flag = GNUNET_NO;
- if (ret->blen < sarg->slen + ret->slen)
- sb_realloc (ret, ret->blen + sarg->slen + 128);
- memcpy (&ret->sbuf[ret->slen],
- sarg->sbuf,
- sarg->slen);
- ret->slen += sarg->slen;
-}
-
-
-/**
- * Append a C string.
- *
- * @param ret where to write the result
- * @param cstr string to append
- */
-static void
-sb_append_cstr (struct StringBuffer *ret,
- const char *cstr)
-{
- size_t cstr_len = strlen (cstr);
-
- if (GNUNET_YES == ret->null_flag)
- ret->slen = 0;
- ret->null_flag = GNUNET_NO;
- if (ret->blen < cstr_len + ret->slen)
- sb_realloc (ret, ret->blen + cstr_len + 128);
- memcpy (&ret->sbuf[ret->slen],
- cstr,
- cstr_len);
- ret->slen += cstr_len;
-}
-
-
-/**
- * Wrap a string buffer, that is, set ret to the format string
- * which contains an "%s" which is to be replaced with the original
- * content of 'ret'. Note that optimizing this function is not
- * really worth it, it is rarely called.
- *
- * @param ret where to write the result and take the input for %.*s from
- * @param format format string, fprintf-style, with exactly one "%.*s"
- * @param extra_chars how long will the result be, in addition to 'sarg' length
- */
-static void
-sb_wrap (struct StringBuffer *ret,
- const char *format,
- size_t extra_chars)
-{
- char *temp;
-
- if (GNUNET_YES == ret->null_flag)
- ret->slen = 0;
- ret->null_flag = GNUNET_NO;
- temp = GNUNET_malloc (ret->slen + extra_chars + 1);
- GNUNET_snprintf (temp,
- ret->slen + extra_chars + 1,
- format,
- (int) ret->slen,
- ret->sbuf);
- GNUNET_free_non_null (ret->abuf);
- ret->abuf = temp;
- ret->sbuf = temp;
- ret->blen = ret->slen + extra_chars + 1;
- ret->slen = ret->slen + extra_chars;
-}
-
-
-/**
- * Format a string buffer. Note that optimizing this function is not
- * really worth it, it is rarely called.
- *
- * @param ret where to write the result
- * @param format format string, fprintf-style, with exactly one "%.*s"
- * @param extra_chars how long will the result be, in addition to 'sarg' length
- * @param sarg string to print into the format
- */
-static void
-sb_printf1 (struct StringBuffer *ret,
- const char *format,
- size_t extra_chars,
- const struct StringBuffer *sarg)
-{
- if (ret->blen < sarg->slen + extra_chars + 1)
- sb_realloc (ret,
- sarg->slen + extra_chars + 1);
- ret->null_flag = GNUNET_NO;
- ret->sbuf = ret->abuf;
- ret->slen = sarg->slen + extra_chars;
- GNUNET_snprintf (ret->sbuf,
- ret->blen,
- format,
- (int) sarg->slen,
- sarg->sbuf);
-}
-
-
-/**
- * Format a string buffer.
- *
- * @param ret where to write the result
- * @param format format string, fprintf-style, with exactly two "%.*s"
- * @param extra_chars how long will the result be, in addition to 'sarg1/2'
length
- * @param sarg1 first string to print into the format
- * @param sarg2 second string to print into the format
- */
-static void
-sb_printf2 (struct StringBuffer *ret,
- const char *format,
- size_t extra_chars,
- const struct StringBuffer *sarg1,
- const struct StringBuffer *sarg2)
-{
- if (ret->blen < sarg1->slen + sarg2->slen + extra_chars + 1)
- sb_realloc (ret,
- sarg1->slen + sarg2->slen + extra_chars + 1);
- ret->null_flag = GNUNET_NO;
- ret->slen = sarg1->slen + sarg2->slen + extra_chars;
- ret->sbuf = ret->abuf;
- GNUNET_snprintf (ret->sbuf,
- ret->blen,
- format,
- (int) sarg1->slen,
- sarg1->sbuf,
- (int) sarg2->slen,
- sarg2->sbuf);
-}
-
-
-/**
- * Format a string buffer. Note that optimizing this function is not
- * really worth it, it is rarely called.
- *
- * @param ret where to write the result
- * @param format format string, fprintf-style, with exactly three "%.*s"
- * @param extra_chars how long will the result be, in addition to 'sarg1/2/3'
length
- * @param sarg1 first string to print into the format
- * @param sarg2 second string to print into the format
- * @param sarg3 third string to print into the format
- */
-static void
-sb_printf3 (struct StringBuffer *ret,
- const char *format,
- size_t extra_chars,
- const struct StringBuffer *sarg1,
- const struct StringBuffer *sarg2,
- const struct StringBuffer *sarg3)
-{
- if (ret->blen < sarg1->slen + sarg2->slen + sarg3->slen + extra_chars + 1)
- sb_realloc (ret,
- sarg1->slen + sarg2->slen + sarg3->slen + extra_chars + 1);
- ret->null_flag = GNUNET_NO;
- ret->slen = sarg1->slen + sarg2->slen + sarg3->slen + extra_chars;
- ret->sbuf = ret->abuf;
- GNUNET_snprintf (ret->sbuf,
- ret->blen,
- format,
- (int) sarg1->slen,
- sarg1->sbuf,
- (int) sarg2->slen,
- sarg2->sbuf,
- (int) sarg3->slen,
- sarg3->sbuf);
-}
-
-
-/**
- * Free resources of the given string buffer.
- *
- * @param sb buffer to free (actual pointer is not freed, as they
- * should not be individually allocated)
- */
-static void
-sb_free (struct StringBuffer *sb)
-{
- GNUNET_array_grow (sb->abuf,
- sb->blen,
- 0);
- sb->slen = 0;
- sb->sbuf = NULL;
- sb->null_flag= GNUNET_YES;
-}
-
-
-/**
- * Copy the given string buffer from 'in' to 'out'.
- *
- * @param in input string
- * @param out output string
- */
-static void
-sb_strdup (struct StringBuffer *out,
- const struct StringBuffer *in)
-
-{
- out->null_flag = in->null_flag;
- if (GNUNET_YES == out->null_flag)
- return;
- if (out->blen < in->slen)
- {
- GNUNET_array_grow (out->abuf,
- out->blen,
- in->slen);
- }
- out->sbuf = out->abuf;
- out->slen = in->slen;
- memcpy (out->sbuf, in->sbuf, out->slen);
-}
-
-
-/**
- * Copy the given string buffer from 'in' to 'out'.
- *
- * @param cstr input string
- * @param out output string
- */
-static void
-sb_strdup_cstr (struct StringBuffer *out,
- const char *cstr)
-{
- if (NULL == cstr)
- {
- out->null_flag = GNUNET_YES;
- return;
- }
- out->null_flag = GNUNET_NO;
- out->slen = strlen (cstr);
- if (out->blen < out->slen)
- {
- GNUNET_array_grow (out->abuf,
- out->blen,
- out->slen);
- }
- out->sbuf = out->abuf;
- memcpy (out->sbuf, cstr, out->slen);
-}
-
-
-/**
- * Check if the given string 'str' needs parentheses around it when
- * using it to generate a regex.
- *
- * @param str string
- *
- * @return GNUNET_YES if parentheses are needed, GNUNET_NO otherwise
- */
-static int
-needs_parentheses (const struct StringBuffer *str)
-{
- size_t slen;
- const char *op;
- const char *cl;
- const char *pos;
- const char *end;
- unsigned int cnt;
-
- if ((GNUNET_YES == str->null_flag) || ((slen = str->slen) < 2))
- return GNUNET_NO;
- pos = str->sbuf;
- if ('(' != pos[0])
- return GNUNET_YES;
- end = str->sbuf + slen;
- cnt = 1;
- pos++;
- while (cnt > 0)
- {
- cl = memchr (pos, ')', end - pos);
- if (NULL == cl)
- {
- GNUNET_break (0);
- return GNUNET_YES;
- }
- /* while '(' before ')', count opening parens */
- while ( (NULL != (op = memchr (pos, '(', end - pos))) &&
- (op < cl) )
- {
- cnt++;
- pos = op + 1;
- }
- /* got ')' first */
- cnt--;
- pos = cl + 1;
- }
- return (*pos == '\0') ? GNUNET_NO : GNUNET_YES;
-}
-
-
-/**
- * Remove parentheses surrounding string 'str'.
- * Example: "(a)" becomes "a", "(a|b)|(a|c)" stays the same.
- * You need to GNUNET_free the returned string.
- *
- * @param str string, modified to contain a
- * @return string without surrounding parentheses, string 'str' if no preceding
- * epsilon could be found, NULL if 'str' was NULL
- */
-static void
-remove_parentheses (struct StringBuffer *str)
-{
- size_t slen;
- const char *pos;
- const char *end;
- const char *sbuf;
- const char *op;
- const char *cp;
- unsigned int cnt;
-
- if (0)
- return;
- sbuf = str->sbuf;
- if ( (GNUNET_YES == str->null_flag) ||
- (1 >= (slen = str->slen)) ||
- ('(' != str->sbuf[0]) ||
- (')' != str->sbuf[slen - 1]) )
- return;
- cnt = 0;
- pos = &sbuf[1];
- end = &sbuf[slen - 1];
- op = memchr (pos, '(', end - pos);
- cp = memchr (pos, ')', end - pos);
- while (NULL != cp)
- {
- while ( (NULL != op) &&
- (op < cp) )
- {
- cnt++;
- pos = op + 1;
- op = memchr (pos, '(', end - pos);
- }
- while ( (NULL != cp) &&
- ( (NULL == op) ||
- (cp < op) ) )
- {
- if (0 == cnt)
- return; /* can't strip parens */
- cnt--;
- pos = cp + 1;
- cp = memchr (pos, ')', end - pos);
- }
- }
- if (0 != cnt)
- {
- GNUNET_break (0);
- return;
- }
- str->sbuf++;
- str->slen -= 2;
-}
-
-
-/**
- * Check if the string 'str' starts with an epsilon (empty string).
- * Example: "(|a)" is starting with an epsilon.
- *
- * @param str string to test
- *
- * @return 0 if str has no epsilon, 1 if str starts with '(|' and ends with ')'
- */
-static int
-has_epsilon (const struct StringBuffer *str)
-{
- return
- (GNUNET_YES != str->null_flag) &&
- (0 < str->slen) &&
- ('(' == str->sbuf[0]) &&
- ('|' == str->sbuf[1]) &&
- (')' == str->sbuf[str->slen - 1]);
-}
-
-
-/**
- * Remove an epsilon from the string str. Where epsilon is an empty string
- * Example: str = "(|a|b|c)", result: "a|b|c"
- * The returned string needs to be freed.
- *
- * @param str original string
- * @param ret where to return string without preceding epsilon, string 'str'
if no preceding
- * epsilon could be found, NULL if 'str' was NULL
- */
-static void
-remove_epsilon (const struct StringBuffer *str,
- struct StringBuffer *ret)
-{
- if (GNUNET_YES == str->null_flag)
- {
- ret->null_flag = GNUNET_YES;
- return;
- }
- if ( (str->slen > 1) &&
- ('(' == str->sbuf[0]) &&
- ('|' == str->sbuf[1]) &&
- (')' == str->sbuf[str->slen - 1]) )
- {
- /* remove epsilon */
- if (ret->blen < str->slen - 3)
- {
- GNUNET_array_grow (ret->abuf,
- ret->blen,
- str->slen - 3);
- }
- ret->sbuf = ret->abuf;
- ret->slen = str->slen - 3;
- memcpy (ret->sbuf, &str->sbuf[2], ret->slen);
- return;
- }
- sb_strdup (ret, str);
-}
-
-
-/**
- * Compare n bytes of 'str1' and 'str2'
- *
- * @param str1 first string to compare
- * @param str2 second string for comparison
- * @param n number of bytes to compare
- *
- * @return -1 if any of the strings is NULL, 0 if equal, non 0 otherwise
- */
-static int
-sb_strncmp (const struct StringBuffer *str1,
- const struct StringBuffer *str2, size_t n)
-{
- size_t max;
-
- if ( (str1->slen != str2->slen) &&
- ( (str1->slen < n) ||
- (str2->slen < n) ) )
- return -1;
- max = GNUNET_MAX (str1->slen, str2->slen);
- if (max > n)
- max = n;
- return memcmp (str1->sbuf, str2->sbuf, max);
-}
-
-
-/**
- * Compare n bytes of 'str1' and 'str2'
- *
- * @param str1 first string to compare
- * @param str2 second C string for comparison
- * @param n number of bytes to compare (and length of str2)
- *
- * @return -1 if any of the strings is NULL, 0 if equal, non 0 otherwise
- */
-static int
-sb_strncmp_cstr (const struct StringBuffer *str1,
- const char *str2, size_t n)
-{
- if (str1->slen < n)
- return -1;
- return memcmp (str1->sbuf, str2, n);
-}
-
-
-/**
- * Initialize string buffer for storing strings of up to n
- * characters.
- *
- * @param sb buffer to initialize
- * @param n desired target length
- */
-static void
-sb_init (struct StringBuffer *sb,
- size_t n)
-{
- sb->null_flag = GNUNET_NO;
- sb->abuf = sb->sbuf = (0 == n) ? NULL : GNUNET_malloc (n);
- sb->blen = n;
- sb->slen = 0;
-}
-
-
-/**
- * Compare 'str1', starting from position 'k', with whole 'str2'
- *
- * @param str1 first string to compare, starting from position 'k'
- * @param str2 second string for comparison
- * @param k starting position in 'str1'
- *
- * @return -1 if any of the strings is NULL, 0 if equal, non 0 otherwise
- */
-static int
-sb_strkcmp (const struct StringBuffer *str1,
- const struct StringBuffer *str2, size_t k)
-{
- if ( (GNUNET_YES == str1->null_flag) ||
- (GNUNET_YES == str2->null_flag) ||
- (k > str1->slen) ||
- (str1->slen - k != str2->slen) )
- return -1;
- return memcmp (&str1->sbuf[k], str2->sbuf, str2->slen);
-}
-
-
-/**
- * Helper function used as 'action' in 'REGEX_ITERNAL_automaton_traverse'
- * function to create the depth-first numbering of the states.
- *
- * @param cls states array.
- * @param count current state counter.
- * @param s current state.
- */
-static void
-number_states (void *cls, const unsigned int count,
- struct REGEX_ITERNAL_State *s)
-{
- struct REGEX_ITERNAL_State **states = cls;
-
- s->dfs_id = count;
- if (NULL != states)
- states[count] = s;
-}
-
-
-
-#define PRIS(a) \
- ((GNUNET_YES == a.null_flag) ? 6 : (int) a.slen), \
- ((GNUNET_YES == a.null_flag) ? "(null)" : a.sbuf)
-
-
-/**
- * Construct the regular expression given the inductive step,
- * $R^{(k)}_{ij} = R^{(k-1)}_{ij} | R^{(k-1)}_{ik} ( R^{(k-1)}_{kk} )^*
- * R^{(k-1)}_{kj}, and simplify the resulting expression saved in R_cur_ij.
- *
- * @param R_last_ij value of $R^{(k-1)_{ij}.
- * @param R_last_ik value of $R^{(k-1)_{ik}.
- * @param R_last_kk value of $R^{(k-1)_{kk}.
- * @param R_last_kj value of $R^{(k-1)_{kj}.
- * @param R_cur_ij result for this inductive step is saved in R_cur_ij,
R_cur_ij
- * is expected to be NULL when called!
- * @param R_cur_l optimization -- kept between iterations to avoid realloc
- * @param R_cur_r optimization -- kept between iterations to avoid realloc
- */
-static void
-automaton_create_proofs_simplify (const struct StringBuffer *R_last_ij,
- const struct StringBuffer *R_last_ik,
- const struct StringBuffer *R_last_kk,
- const struct StringBuffer *R_last_kj,
- struct StringBuffer *R_cur_ij,
- struct StringBuffer *R_cur_l,
- struct StringBuffer *R_cur_r)
-{
- struct StringBuffer R_temp_ij;
- struct StringBuffer R_temp_ik;
- struct StringBuffer R_temp_kj;
- struct StringBuffer R_temp_kk;
- int eps_check;
- int ij_ik_cmp;
- int ij_kj_cmp;
- int ik_kk_cmp;
- int kk_kj_cmp;
- int clean_ik_kk_cmp;
- int clean_kk_kj_cmp;
- size_t length;
- size_t length_l;
- size_t length_r;
-
- /*
- * $R^{(k)}_{ij} = R^{(k-1)}_{ij} | R^{(k-1)}_{ik} ( R^{(k-1)}_{kk} )^*
R^{(k-1)}_{kj}
- * R_last == R^{(k-1)}, R_cur == R^{(k)}
- * R_cur_ij = R_cur_l | R_cur_r
- * R_cur_l == R^{(k-1)}_{ij}
- * R_cur_r == R^{(k-1)}_{ik} ( R^{(k-1)}_{kk} )^* R^{(k-1)}_{kj}
- */
-
- if ( (GNUNET_YES == R_last_ij->null_flag) &&
- ( (GNUNET_YES == R_last_ik->null_flag) ||
- (GNUNET_YES == R_last_kj->null_flag)))
- {
- /* R^{(k)}_{ij} = N | N */
- R_cur_ij->null_flag = GNUNET_YES;
- R_cur_ij->synced = GNUNET_NO;
- return;
- }
-
- if ( (GNUNET_YES == R_last_ik->null_flag) ||
- (GNUNET_YES == R_last_kj->null_flag) )
- {
- /* R^{(k)}_{ij} = R^{(k-1)}_{ij} | N */
- if (GNUNET_YES == R_last_ij->synced)
- {
- R_cur_ij->synced = GNUNET_YES;
- R_cur_ij->null_flag = GNUNET_NO;
- return;
- }
- R_cur_ij->synced = GNUNET_YES;
- sb_strdup (R_cur_ij, R_last_ij);
- return;
- }
- R_cur_ij->synced = GNUNET_NO;
-
- /* $R^{(k)}_{ij} = N | R^{(k-1)}_{ik} ( R^{(k-1)}_{kk} )^* R^{(k-1)}_{kj} OR
- * $R^{(k)}_{ij} = R^{(k-1)}_{ij} | R^{(k-1)}_{ik} ( R^{(k-1)}_{kk} )^*
R^{(k-1)}_{kj} */
-
- R_cur_r->null_flag = GNUNET_YES;
- R_cur_r->slen = 0;
- R_cur_l->null_flag = GNUNET_YES;
- R_cur_l->slen = 0;
-
- /* cache results from strcmp, we might need these many times */
- ij_kj_cmp = sb_nullstrcmp (R_last_ij, R_last_kj);
- ij_ik_cmp = sb_nullstrcmp (R_last_ij, R_last_ik);
- ik_kk_cmp = sb_nullstrcmp (R_last_ik, R_last_kk);
- kk_kj_cmp = sb_nullstrcmp (R_last_kk, R_last_kj);
-
- /* Assign R_temp_(ik|kk|kj) to R_last[][] and remove epsilon as well
- * as parentheses, so we can better compare the contents */
-
- memset (&R_temp_ij, 0, sizeof (struct StringBuffer));
- memset (&R_temp_ik, 0, sizeof (struct StringBuffer));
- memset (&R_temp_kk, 0, sizeof (struct StringBuffer));
- memset (&R_temp_kj, 0, sizeof (struct StringBuffer));
- remove_epsilon (R_last_ik, &R_temp_ik);
- remove_epsilon (R_last_kk, &R_temp_kk);
- remove_epsilon (R_last_kj, &R_temp_kj);
- remove_parentheses (&R_temp_ik);
- remove_parentheses (&R_temp_kk);
- remove_parentheses (&R_temp_kj);
- clean_ik_kk_cmp = sb_nullstrcmp (R_last_ik, &R_temp_kk);
- clean_kk_kj_cmp = sb_nullstrcmp (&R_temp_kk, R_last_kj);
-
- /* construct R_cur_l (and, if necessary R_cur_r) */
- if (GNUNET_YES != R_last_ij->null_flag)
- {
- /* Assign R_temp_ij to R_last_ij and remove epsilon as well
- * as parentheses, so we can better compare the contents */
- remove_epsilon (R_last_ij, &R_temp_ij);
- remove_parentheses (&R_temp_ij);
-
- if ( (0 == sb_strcmp (&R_temp_ij, &R_temp_ik)) &&
- (0 == sb_strcmp (&R_temp_ik, &R_temp_kk)) &&
- (0 == sb_strcmp (&R_temp_kk, &R_temp_kj)) )
- {
- if (0 == R_temp_ij.slen)
- {
- R_cur_r->null_flag = GNUNET_NO;
- }
- else if ((0 == sb_strncmp_cstr (R_last_ij, "(|", 2)) ||
- (0 == sb_strncmp_cstr (R_last_ik, "(|", 2) &&
- 0 == sb_strncmp_cstr (R_last_kj, "(|", 2)))
- {
- /*
- * a|(e|a)a*(e|a) = a*
- * a|(e|a)(e|a)*(e|a) = a*
- * (e|a)|aa*a = a*
- * (e|a)|aa*(e|a) = a*
- * (e|a)|(e|a)a*a = a*
- * (e|a)|(e|a)a*(e|a) = a*
- * (e|a)|(e|a)(e|a)*(e|a) = a*
- */
- if (GNUNET_YES == needs_parentheses (&R_temp_ij))
- sb_printf1 (R_cur_r, "(%.*s)*", 3, &R_temp_ij);
- else
- sb_printf1 (R_cur_r, "%.*s*", 1, &R_temp_ij);
- }
- else
- {
- /*
- * a|aa*a = a+
- * a|(e|a)a*a = a+
- * a|aa*(e|a) = a+
- * a|(e|a)(e|a)*a = a+
- * a|a(e|a)*(e|a) = a+
- */
- if (GNUNET_YES == needs_parentheses (&R_temp_ij))
- sb_printf1 (R_cur_r, "(%.*s)+", 3, &R_temp_ij);
- else
- sb_printf1 (R_cur_r, "%.*s+", 1, &R_temp_ij);
- }
- }
- else if ( (0 == ij_ik_cmp) && (0 == clean_kk_kj_cmp) && (0 !=
clean_ik_kk_cmp) )
- {
- /* a|ab*b = ab* */
- if (0 == R_last_kk->slen)
- sb_strdup (R_cur_r, R_last_ij);
- else if (GNUNET_YES == needs_parentheses (&R_temp_kk))
- sb_printf2 (R_cur_r, "%.*s(%.*s)*", 3, R_last_ij, &R_temp_kk);
- else
- sb_printf2 (R_cur_r, "%.*s%.*s*", 1, R_last_ij, R_last_kk);
- R_cur_l->null_flag = GNUNET_YES;
- }
- else if ( (0 == ij_kj_cmp) && (0 == clean_ik_kk_cmp) && (0 !=
clean_kk_kj_cmp))
- {
- /* a|bb*a = b*a */
- if (R_last_kk->slen < 1)
- {
- sb_strdup (R_cur_r, R_last_kj);
- }
- else if (GNUNET_YES == needs_parentheses (&R_temp_kk))
- sb_printf2 (R_cur_r, "(%.*s)*%.*s", 3, &R_temp_kk, R_last_kj);
- else
- sb_printf2 (R_cur_r, "%.*s*%.*s", 1, &R_temp_kk, R_last_kj);
-
- R_cur_l->null_flag = GNUNET_YES;
- }
- else if ( (0 == ij_ik_cmp) && (0 == kk_kj_cmp) && (! has_epsilon
(R_last_ij)) &&
- has_epsilon (R_last_kk))
- {
- /* a|a(e|b)*(e|b) = a|ab* = a|a|ab|abb|abbb|... = ab* */
- if (needs_parentheses (&R_temp_kk))
- sb_printf2 (R_cur_r, "%.*s(%.*s)*", 3, R_last_ij, &R_temp_kk);
- else
- sb_printf2 (R_cur_r, "%.*s%.*s*", 1, R_last_ij, &R_temp_kk);
- R_cur_l->null_flag = GNUNET_YES;
- }
- else if ( (0 == ij_kj_cmp) && (0 == ik_kk_cmp) && (! has_epsilon
(R_last_ij)) &&
- has_epsilon (R_last_kk))
- {
- /* a|(e|b)(e|b)*a = a|b*a = a|a|ba|bba|bbba|... = b*a */
- if (needs_parentheses (&R_temp_kk))
- sb_printf2 (R_cur_r, "(%.*s)*%.*s", 3, &R_temp_kk, R_last_ij);
- else
- sb_printf2 (R_cur_r, "%.*s*%.*s", 1, &R_temp_kk, R_last_ij);
- R_cur_l->null_flag = GNUNET_YES;
- }
- else
- {
- sb_strdup (R_cur_l, R_last_ij);
- remove_parentheses (R_cur_l);
- }
- }
- else
- {
- /* we have no left side */
- R_cur_l->null_flag = GNUNET_YES;
- }
-
- /* construct R_cur_r, if not already constructed */
- if (GNUNET_YES == R_cur_r->null_flag)
- {
- length = R_temp_kk.slen - R_last_ik->slen;
-
- /* a(ba)*bx = (ab)+x */
- if ( (length > 0) &&
- (GNUNET_YES != R_last_kk->null_flag) &&
- (0 < R_last_kk->slen) &&
- (GNUNET_YES != R_last_kj->null_flag) &&
- (0 < R_last_kj->slen) &&
- (GNUNET_YES != R_last_ik->null_flag) &&
- (0 < R_last_ik->slen) &&
- (0 == sb_strkcmp (&R_temp_kk, R_last_ik, length)) &&
- (0 == sb_strncmp (&R_temp_kk, R_last_kj, length)) )
- {
- struct StringBuffer temp_a;
- struct StringBuffer temp_b;
-
- sb_init (&temp_a, length);
- sb_init (&temp_b, R_last_kj->slen - length);
-
- length_l = length;
- temp_a.sbuf = temp_a.abuf;
- memcpy (temp_a.sbuf, R_last_kj->sbuf, length_l);
- temp_a.slen = length_l;
-
- length_r = R_last_kj->slen - length;
- temp_b.sbuf = temp_b.abuf;
- memcpy (temp_b.sbuf, &R_last_kj->sbuf[length], length_r);
- temp_b.slen = length_r;
-
- /* e|(ab)+ = (ab)* */
- if ( (GNUNET_YES != R_cur_l->null_flag) &&
- (0 == R_cur_l->slen) &&
- (0 == temp_b.slen) )
- {
- sb_printf2 (R_cur_r, "(%.*s%.*s)*", 3, R_last_ik, &temp_a);
- sb_free (R_cur_l);
- R_cur_l->null_flag = GNUNET_YES;
- }
- else
- {
- sb_printf3 (R_cur_r, "(%.*s%.*s)+%.*s", 3, R_last_ik, &temp_a,
&temp_b);
- }
- sb_free (&temp_a);
- sb_free (&temp_b);
- }
- else if (0 == sb_strcmp (&R_temp_ik, &R_temp_kk) &&
- 0 == sb_strcmp (&R_temp_kk, &R_temp_kj))
- {
- /*
- * (e|a)a*(e|a) = a*
- * (e|a)(e|a)*(e|a) = a*
- */
- if (has_epsilon (R_last_ik) && has_epsilon (R_last_kj))
- {
- if (needs_parentheses (&R_temp_kk))
- sb_printf1 (R_cur_r, "(%.*s)*", 3, &R_temp_kk);
- else
- sb_printf1 (R_cur_r, "%.*s*", 1, &R_temp_kk);
- }
- /* aa*a = a+a */
- else if ( (0 == clean_ik_kk_cmp) &&
- (0 == clean_kk_kj_cmp) &&
- (! has_epsilon (R_last_ik)) )
- {
- if (needs_parentheses (&R_temp_kk))
- sb_printf2 (R_cur_r, "(%.*s)+%.*s", 3, &R_temp_kk, &R_temp_kk);
- else
- sb_printf2 (R_cur_r, "%.*s+%.*s", 1, &R_temp_kk, &R_temp_kk);
- }
- /*
- * (e|a)a*a = a+
- * aa*(e|a) = a+
- * a(e|a)*(e|a) = a+
- * (e|a)a*a = a+
- */
- else
- {
- eps_check =
- (has_epsilon (R_last_ik) + has_epsilon (R_last_kk) +
- has_epsilon (R_last_kj));
-
- if (1 == eps_check)
- {
- if (needs_parentheses (&R_temp_kk))
- sb_printf1 (R_cur_r, "(%.*s)+", 3, &R_temp_kk);
- else
- sb_printf1 (R_cur_r, "%.*s+", 1, &R_temp_kk);
- }
- }
- }
- /*
- * aa*b = a+b
- * (e|a)(e|a)*b = a*b
- */
- else if (0 == sb_strcmp (&R_temp_ik, &R_temp_kk))
- {
- if (has_epsilon (R_last_ik))
- {
- if (needs_parentheses (&R_temp_kk))
- sb_printf2 (R_cur_r, "(%.*s)*%.*s", 3, &R_temp_kk, R_last_kj);
- else
- sb_printf2 (R_cur_r, "%.*s*%.*s", 1, &R_temp_kk, R_last_kj);
- }
- else
- {
- if (needs_parentheses (&R_temp_kk))
- sb_printf2 (R_cur_r, "(%.*s)+%.*s", 3, &R_temp_kk, R_last_kj);
- else
- sb_printf2 (R_cur_r, "%.*s+%.*s", 1, &R_temp_kk, R_last_kj);
- }
- }
- /*
- * ba*a = ba+
- * b(e|a)*(e|a) = ba*
- */
- else if (0 == sb_strcmp (&R_temp_kk, &R_temp_kj))
- {
- if (has_epsilon (R_last_kj))
- {
- if (needs_parentheses (&R_temp_kk))
- sb_printf2 (R_cur_r, "%.*s(%.*s)*", 3, R_last_ik, &R_temp_kk);
- else
- sb_printf2 (R_cur_r, "%.*s%.*s*", 1, R_last_ik, &R_temp_kk);
- }
- else
- {
- if (needs_parentheses (&R_temp_kk))
- sb_printf2 (R_cur_r, "(%.*s)+%.*s", 3, R_last_ik, &R_temp_kk);
- else
- sb_printf2 (R_cur_r, "%.*s+%.*s", 1, R_last_ik, &R_temp_kk);
- }
- }
- else
- {
- if (0 < R_temp_kk.slen)
- {
- if (needs_parentheses (&R_temp_kk))
- {
- sb_printf3 (R_cur_r, "%.*s(%.*s)*%.*s", 3, R_last_ik, &R_temp_kk,
- R_last_kj);
- }
- else
- {
- sb_printf3 (R_cur_r, "%.*s%.*s*%.*s", 1, R_last_ik, &R_temp_kk,
- R_last_kj);
- }
- }
- else
- {
- sb_printf2 (R_cur_r, "%.*s%.*s", 0, R_last_ik, R_last_kj);
- }
- }
- }
- sb_free (&R_temp_ij);
- sb_free (&R_temp_ik);
- sb_free (&R_temp_kk);
- sb_free (&R_temp_kj);
-
- if ( (GNUNET_YES == R_cur_l->null_flag) &&
- (GNUNET_YES == R_cur_r->null_flag) )
- {
- R_cur_ij->null_flag = GNUNET_YES;
- return;
- }
-
- if ( (GNUNET_YES != R_cur_l->null_flag) &&
- (GNUNET_YES == R_cur_r->null_flag) )
- {
- struct StringBuffer tmp;
-
- tmp = *R_cur_ij;
- *R_cur_ij = *R_cur_l;
- *R_cur_l = tmp;
- return;
- }
-
- if ( (GNUNET_YES == R_cur_l->null_flag) &&
- (GNUNET_YES != R_cur_r->null_flag) )
- {
- struct StringBuffer tmp;
-
- tmp = *R_cur_ij;
- *R_cur_ij = *R_cur_r;
- *R_cur_r = tmp;
- return;
- }
-
- if (0 == sb_nullstrcmp (R_cur_l, R_cur_r))
- {
- struct StringBuffer tmp;
-
- tmp = *R_cur_ij;
- *R_cur_ij = *R_cur_l;
- *R_cur_l = tmp;
- return;
- }
- sb_printf2 (R_cur_ij, "(%.*s|%.*s)", 3, R_cur_l, R_cur_r);
-}
-
-
-/**
- * Create proofs for all states in the given automaton. Implementation of the
- * algorithm descriped in chapter 3.2.1 of "Automata Theory, Languages, and
- * Computation 3rd Edition" by Hopcroft, Motwani and Ullman.
- *
- * Each state in the automaton gets assigned 'proof' and 'hash' (hash of the
- * proof) fields. The starting state will only have a valid proof/hash if it
has
- * any incoming transitions.
- *
- * @param a automaton for which to assign proofs and hashes, must not be NULL
- */
-static int
-automaton_create_proofs (struct REGEX_ITERNAL_Automaton *a)
-{
- unsigned int n = a->state_count;
- struct REGEX_ITERNAL_State *states[n];
- struct StringBuffer *R_last;
- struct StringBuffer *R_cur;
- struct StringBuffer R_cur_r;
- struct StringBuffer R_cur_l;
- struct StringBuffer *R_swap;
- struct REGEX_ITERNAL_Transition *t;
- struct StringBuffer complete_regex;
- unsigned int i;
- unsigned int j;
- unsigned int k;
-
- R_last = GNUNET_malloc_large (sizeof (struct StringBuffer) * n * n);
- R_cur = GNUNET_malloc_large (sizeof (struct StringBuffer) * n * n);
- if ( (NULL == R_last) ||
- (NULL == R_cur) )
- {
- GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "malloc");
- GNUNET_free_non_null (R_cur);
- GNUNET_free_non_null (R_last);
- return GNUNET_SYSERR;
- }
-
- /* create depth-first numbering of the states, initializes 'state' */
- REGEX_ITERNAL_automaton_traverse (a, a->start, NULL, NULL, &number_states,
- states);
-
- for (i = 0; i < n; i++)
- GNUNET_assert (NULL != states[i]);
- for (i = 0; i < n; i++)
- for (j = 0; j < n; j++)
- R_last[i *n + j].null_flag = GNUNET_YES;
-
- /* Compute regular expressions of length "1" between each pair of states */
- for (i = 0; i < n; i++)
- {
- for (t = states[i]->transitions_head; NULL != t; t = t->next)
- {
- j = t->to_state->dfs_id;
- if (GNUNET_YES == R_last[i * n + j].null_flag)
- {
- sb_strdup_cstr (&R_last[i * n + j], t->label);
- }
- else
- {
- sb_append_cstr (&R_last[i * n + j], "|");
- sb_append_cstr (&R_last[i * n + j], t->label);
- }
- }
- /* add self-loop: i is reachable from i via epsilon-transition */
- if (GNUNET_YES == R_last[i * n + i].null_flag)
- {
- R_last[i * n + i].slen = 0;
- R_last[i * n + i].null_flag = GNUNET_NO;
- }
- else
- {
- sb_wrap (&R_last[i * n + i], "(|%.*s)", 3);
- }
- }
- for (i = 0; i < n; i++)
- for (j = 0; j < n; j++)
- if (needs_parentheses (&R_last[i * n + j]))
- sb_wrap (&R_last[i * n + j], "(%.*s)", 2);
- /* Compute regular expressions of length "k" between each pair of states per
- * induction */
- memset (&R_cur_l, 0, sizeof (struct StringBuffer));
- memset (&R_cur_r, 0, sizeof (struct StringBuffer));
- for (k = 0; k < n; k++)
- {
- for (i = 0; i < n; i++)
- {
- for (j = 0; j < n; j++)
- {
- /* Basis for the recursion:
- * $R^{(k)}_{ij} = R^{(k-1)}_{ij} | R^{(k-1)}_{ik} ( R^{(k-1)}_{kk}
)^* R^{(k-1)}_{kj}
- * R_last == R^{(k-1)}, R_cur == R^{(k)}
- */
-
- /* Create R_cur[i][j] and simplify the expression */
- automaton_create_proofs_simplify (&R_last[i * n + j], &R_last[i * n +
k],
- &R_last[k * n + k], &R_last[k * n +
j],
- &R_cur[i * n + j],
- &R_cur_l, &R_cur_r);
- }
- }
- /* set R_last = R_cur */
- R_swap = R_last;
- R_last = R_cur;
- R_cur = R_swap;
- /* clear 'R_cur' for next iteration */
- for (i = 0; i < n; i++)
- for (j = 0; j < n; j++)
- R_cur[i * n + j].null_flag = GNUNET_YES;
- }
- sb_free (&R_cur_l);
- sb_free (&R_cur_r);
- /* assign proofs and hashes */
- for (i = 0; i < n; i++)
- {
- if (GNUNET_YES != R_last[a->start->dfs_id * n + i].null_flag)
- {
- states[i]->proof = GNUNET_strndup (R_last[a->start->dfs_id * n + i].sbuf,
- R_last[a->start->dfs_id * n + i].slen);
- GNUNET_CRYPTO_hash (states[i]->proof, strlen (states[i]->proof),
- &states[i]->hash);
- }
- }
-
- /* complete regex for whole DFA: union of all pairs (start state/accepting
- * state(s)). */
- sb_init (&complete_regex, 16 * n);
- for (i = 0; i < n; i++)
- {
- if (states[i]->accepting)
- {
- if ( (0 == complete_regex.slen) &&
- (0 < R_last[a->start->dfs_id * n + i].slen) )
- {
- sb_append (&complete_regex,
- &R_last[a->start->dfs_id * n + i]);
- }
- else if ( (GNUNET_YES != R_last[a->start->dfs_id * n + i].null_flag) &&
- (0 < R_last[a->start->dfs_id * n + i].slen) )
- {
- sb_append_cstr (&complete_regex, "|");
- sb_append (&complete_regex,
- &R_last[a->start->dfs_id * n + i]);
- }
- }
- }
- a->canonical_regex = GNUNET_strndup (complete_regex.sbuf,
complete_regex.slen);
-
- /* cleanup */
- sb_free (&complete_regex);
- for (i = 0; i < n; i++)
- for (j = 0; j < n; j++)
- {
- sb_free (&R_cur[i * n + j]);
- sb_free (&R_last[i * n + j]);
- }
- GNUNET_free (R_cur);
- GNUNET_free (R_last);
- return GNUNET_OK;
-}
-
-
-/**
- * Creates a new DFA state based on a set of NFA states. Needs to be freed
using
- * automaton_destroy_state.
- *
- * @param ctx context
- * @param nfa_states set of NFA states on which the DFA should be based on
- *
- * @return new DFA state
- */
-static struct REGEX_ITERNAL_State *
-dfa_state_create (struct REGEX_ITERNAL_Context *ctx,
- struct REGEX_ITERNAL_StateSet *nfa_states)
-{
- struct REGEX_ITERNAL_State *s;
- char *pos;
- size_t len;
- struct REGEX_ITERNAL_State *cstate;
- struct REGEX_ITERNAL_Transition *ctran;
- unsigned int i;
-
- s = GNUNET_malloc (sizeof (struct REGEX_ITERNAL_State));
- s->id = ctx->state_id++;
- s->index = -1;
- s->lowlink = -1;
-
- if (NULL == nfa_states)
- {
- GNUNET_asprintf (&s->name, "s%i", s->id);
- return s;
- }
-
- s->nfa_set = *nfa_states;
-
- if (nfa_states->off < 1)
- return s;
-
- /* Create a name based on 'nfa_states' */
- len = nfa_states->off * 14 + 4;
- s->name = GNUNET_malloc (len);
- strcat (s->name, "{");
- pos = s->name + 1;
-
- for (i = 0; i < nfa_states->off; i++)
- {
- cstate = nfa_states->states[i];
- GNUNET_snprintf (pos, pos - s->name + len,
- "%i,", cstate->id);
- pos += strlen (pos);
-
- /* Add a transition for each distinct label to NULL state */
- for (ctran = cstate->transitions_head; NULL != ctran; ctran = ctran->next)
- if (NULL != ctran->label)
- state_add_transition (ctx, s, ctran->label, NULL);
-
- /* If the nfa_states contain an accepting state, the new dfa state is also
- * accepting. */
- if (cstate->accepting)
- s->accepting = 1;
- }
- pos[-1] = '}';
- s->name = GNUNET_realloc (s->name, strlen (s->name) + 1);
-
- memset (nfa_states, 0, sizeof (struct REGEX_ITERNAL_StateSet));
- return s;
-}
-
-
-/**
- * Move from the given state 's' to the next state on transition 'str'.
Consumes
- * as much of the given 'str' as possible (usefull for strided DFAs). On return
- * 's' will point to the next state, and the length of the substring used for
- * this transition will be returned. If no transition possible 0 is returned
and
- * 's' points to NULL.
- *
- * @param s starting state, will point to the next state or NULL (if no
- * transition possible)
- * @param str edge label to follow (will match longest common prefix)
- *
- * @return length of the substring comsumed from 'str'
- */
-static unsigned int
-dfa_move (struct REGEX_ITERNAL_State **s, const char *str)
-{
- struct REGEX_ITERNAL_Transition *t;
- struct REGEX_ITERNAL_State *new_s;
- unsigned int len;
- unsigned int max_len;
-
- if (NULL == s)
- return 0;
-
- new_s = NULL;
- max_len = 0;
- for (t = (*s)->transitions_head; NULL != t; t = t->next)
- {
- len = strlen (t->label);
-
- if (0 == strncmp (t->label, str, len))
- {
- if (len >= max_len)
- {
- max_len = len;
- new_s = t->to_state;
- }
- }
- }
-
- *s = new_s;
- return max_len;
-}
-
-
-/**
- * Set the given state 'marked' to GNUNET_YES. Used by the
- * 'dfa_remove_unreachable_states' function to detect unreachable states in the
- * automaton.
- *
- * @param cls closure, not used.
- * @param count count, not used.
- * @param s state where the marked attribute will be set to GNUNET_YES.
- */
-static void
-mark_states (void *cls, const unsigned int count, struct REGEX_ITERNAL_State
*s)
-{
- s->marked = GNUNET_YES;
-}
-
-
-/**
- * Remove all unreachable states from DFA 'a'. Unreachable states are those
- * states that are not reachable from the starting state.
- *
- * @param a DFA automaton
- */
-static void
-dfa_remove_unreachable_states (struct REGEX_ITERNAL_Automaton *a)
-{
- struct REGEX_ITERNAL_State *s;
- struct REGEX_ITERNAL_State *s_next;
-
- /* 1. unmark all states */
- for (s = a->states_head; NULL != s; s = s->next)
- s->marked = GNUNET_NO;
-
- /* 2. traverse dfa from start state and mark all visited states */
- REGEX_ITERNAL_automaton_traverse (a, a->start, NULL, NULL, &mark_states,
NULL);
-
- /* 3. delete all states that were not visited */
- for (s = a->states_head; NULL != s; s = s_next)
- {
- s_next = s->next;
- if (GNUNET_NO == s->marked)
- automaton_remove_state (a, s);
- }
-}
-
-
-/**
- * Remove all dead states from the DFA 'a'. Dead states are those states that
do
- * not transition to any other state but themselves.
- *
- * @param a DFA automaton
- */
-static void
-dfa_remove_dead_states (struct REGEX_ITERNAL_Automaton *a)
-{
- struct REGEX_ITERNAL_State *s;
- struct REGEX_ITERNAL_State *s_next;
- struct REGEX_ITERNAL_Transition *t;
- int dead;
-
- GNUNET_assert (DFA == a->type);
-
- for (s = a->states_head; NULL != s; s = s_next)
- {
- s_next = s->next;
-
- if (s->accepting)
- continue;
-
- dead = 1;
- for (t = s->transitions_head; NULL != t; t = t->next)
- {
- if (NULL != t->to_state && t->to_state != s)
- {
- dead = 0;
- break;
- }
- }
-
- if (0 == dead)
- continue;
-
- /* state s is dead, remove it */
- automaton_remove_state (a, s);
- }
-}
-
-
-/**
- * Merge all non distinguishable states in the DFA 'a'
- *
- * @param ctx context
- * @param a DFA automaton
- * @return GNUNET_OK on success
- */
-static int
-dfa_merge_nondistinguishable_states (struct REGEX_ITERNAL_Context *ctx,
- struct REGEX_ITERNAL_Automaton *a)
-{
- uint32_t *table;
- struct REGEX_ITERNAL_State *s1;
- struct REGEX_ITERNAL_State *s2;
- struct REGEX_ITERNAL_Transition *t1;
- struct REGEX_ITERNAL_Transition *t2;
- struct REGEX_ITERNAL_State *s1_next;
- struct REGEX_ITERNAL_State *s2_next;
- int change;
- unsigned int num_equal_edges;
- unsigned int i;
- unsigned int state_cnt;
- unsigned long long idx;
- unsigned long long idx1;
-
- if ( (NULL == a) || (0 == a->state_count) )
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "Could not merge nondistinguishable states, automaton was
NULL.\n");
- return GNUNET_SYSERR;
- }
-
- state_cnt = a->state_count;
- table = GNUNET_malloc_large ((sizeof (uint32_t) * state_cnt * state_cnt /
32) + sizeof (uint32_t));
- if (NULL == table)
- {
- GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "malloc");
- return GNUNET_SYSERR;
- }
-
- for (i = 0, s1 = a->states_head; NULL != s1; s1 = s1->next)
- s1->marked = i++;
-
- /* Mark all pairs of accepting/!accepting states */
- for (s1 = a->states_head; NULL != s1; s1 = s1->next)
- for (s2 = a->states_head; NULL != s2; s2 = s2->next)
- if ( (s1->accepting && !s2->accepting) ||
- (!s1->accepting && s2->accepting) )
- {
- idx = s1->marked * state_cnt + s2->marked;
- table[idx / 32] |= (1 << (idx % 32));
- }
-
- /* Find all equal states */
- change = 1;
- while (0 != change)
- {
- change = 0;
- for (s1 = a->states_head; NULL != s1; s1 = s1->next)
- {
- for (s2 = a->states_head; NULL != s2 && s1 != s2; s2 = s2->next)
- {
- idx = s1->marked * state_cnt + s2->marked;
- if (0 != (table[idx / 32] & (1 << (idx % 32))))
- continue;
- num_equal_edges = 0;
- for (t1 = s1->transitions_head; NULL != t1; t1 = t1->next)
- {
- for (t2 = s2->transitions_head; NULL != t2; t2 = t2->next)
- {
- if (0 == strcmp (t1->label, t2->label))
- {
- num_equal_edges++;
- /* same edge, but targets definitively different, so we're
different
- as well */
- if (t1->to_state->marked > t2->to_state->marked)
- idx1 = t1->to_state->marked * state_cnt + t2->to_state->marked;
- else
- idx1 = t2->to_state->marked * state_cnt + t1->to_state->marked;
- if (0 != (table[idx1 / 32] & (1 << (idx1 % 32))))
- {
- table[idx / 32] |= (1 << (idx % 32));
- change = 1; /* changed a marker, need to run again */
- }
- }
- }
- }
- if ( (num_equal_edges != s1->transition_count) ||
- (num_equal_edges != s2->transition_count) )
- {
- /* Make sure ALL edges of possible equal states are the same */
- table[idx / 32] |= (1 << (idx % 32));
- change = 1; /* changed a marker, need to run again */
- }
- }
- }
- }
-
- /* Merge states that are equal */
- for (s1 = a->states_head; NULL != s1; s1 = s1_next)
- {
- s1_next = s1->next;
- for (s2 = a->states_head; NULL != s2 && s1 != s2; s2 = s2_next)
- {
- s2_next = s2->next;
- idx = s1->marked * state_cnt + s2->marked;
- if (0 == (table[idx / 32] & (1 << (idx % 32))))
- automaton_merge_states (ctx, a, s1, s2);
- }
- }
-
- GNUNET_free (table);
- return GNUNET_OK;
-}
-
-
-/**
- * Minimize the given DFA 'a' by removing all unreachable states, removing all
- * dead states and merging all non distinguishable states
- *
- * @param ctx context
- * @param a DFA automaton
- * @return GNUNET_OK on success
- */
-static int
-dfa_minimize (struct REGEX_ITERNAL_Context *ctx,
- struct REGEX_ITERNAL_Automaton *a)
-{
- if (NULL == a)
- return GNUNET_SYSERR;
-
- GNUNET_assert (DFA == a->type);
-
- /* 1. remove unreachable states */
- dfa_remove_unreachable_states (a);
-
- /* 2. remove dead states */
- dfa_remove_dead_states (a);
-
- /* 3. Merge nondistinguishable states */
- if (GNUNET_OK != dfa_merge_nondistinguishable_states (ctx, a))
- return GNUNET_SYSERR;
- return GNUNET_OK;
-}
-
-
-/**
- * Context for adding strided transitions to a DFA.
- */
-struct REGEX_ITERNAL_Strided_Context
-{
- /**
- * Length of the strides.
- */
- const unsigned int stride;
-
- /**
- * Strided transitions DLL. New strided transitions will be stored in this
DLL
- * and afterwards added to the DFA.
- */
- struct REGEX_ITERNAL_Transition *transitions_head;
-
- /**
- * Strided transitions DLL.
- */
- struct REGEX_ITERNAL_Transition *transitions_tail;
-};
-
-
-/**
- * Recursive helper function to add strides to a DFA.
- *
- * @param cls context, contains stride length and strided transitions DLL.
- * @param depth current depth of the depth-first traversal of the graph.
- * @param label current label, string that contains all labels on the path from
- * 'start' to 's'.
- * @param start start state for the depth-first traversal of the graph.
- * @param s current state in the depth-first traversal
- */
-void
-dfa_add_multi_strides_helper (void *cls, const unsigned int depth, char *label,
- struct REGEX_ITERNAL_State *start,
- struct REGEX_ITERNAL_State *s)
-{
- struct REGEX_ITERNAL_Strided_Context *ctx = cls;
- struct REGEX_ITERNAL_Transition *t;
- char *new_label;
-
- if (depth == ctx->stride)
- {
- t = GNUNET_malloc (sizeof (struct REGEX_ITERNAL_Transition));
- t->label = GNUNET_strdup (label);
- t->to_state = s;
- t->from_state = start;
- GNUNET_CONTAINER_DLL_insert (ctx->transitions_head, ctx->transitions_tail,
- t);
- }
- else
- {
- for (t = s->transitions_head; NULL != t; t = t->next)
- {
- /* Do not consider self-loops, because it end's up in too many
- * transitions */
- if (t->to_state == t->from_state)
- continue;
-
- if (NULL != label)
- {
- GNUNET_asprintf (&new_label, "%s%s", label, t->label);
- }
- else
- new_label = GNUNET_strdup (t->label);
-
- dfa_add_multi_strides_helper (cls, (depth + 1), new_label, start,
- t->to_state);
- }
- }
- GNUNET_free_non_null (label);
-}
-
-
-/**
- * Function called for each state in the DFA. Starts a traversal of depth set
in
- * context starting from state 's'.
- *
- * @param cls context.
- * @param count not used.
- * @param s current state.
- */
-void
-dfa_add_multi_strides (void *cls, const unsigned int count,
- struct REGEX_ITERNAL_State *s)
-{
- dfa_add_multi_strides_helper (cls, 0, NULL, s, s);
-}
-
-
-/**
- * Adds multi-strided transitions to the given 'dfa'.
- *
- * @param regex_ctx regex context needed to add transitions to the automaton.
- * @param dfa DFA to which the multi strided transitions should be added.
- * @param stride_len length of the strides.
- */
-void
-REGEX_ITERNAL_dfa_add_multi_strides (struct REGEX_ITERNAL_Context *regex_ctx,
- struct REGEX_ITERNAL_Automaton *dfa,
- const unsigned int stride_len)
-{
- struct REGEX_ITERNAL_Strided_Context ctx = { stride_len, NULL, NULL };
- struct REGEX_ITERNAL_Transition *t;
- struct REGEX_ITERNAL_Transition *t_next;
-
- if (1 > stride_len || GNUNET_YES == dfa->is_multistrided)
- return;
-
- /* Compute the new transitions of given stride_len */
- REGEX_ITERNAL_automaton_traverse (dfa, dfa->start, NULL, NULL,
- &dfa_add_multi_strides, &ctx);
-
- /* Add all the new transitions to the automaton. */
- for (t = ctx.transitions_head; NULL != t; t = t_next)
- {
- t_next = t->next;
- state_add_transition (regex_ctx, t->from_state, t->label, t->to_state);
- GNUNET_CONTAINER_DLL_remove (ctx.transitions_head, ctx.transitions_tail,
t);
- GNUNET_free_non_null (t->label);
- GNUNET_free (t);
- }
-
- /* Mark this automaton as multistrided */
- dfa->is_multistrided = GNUNET_YES;
-}
-
-/**
- * Recursive Helper function for DFA path compression. Does DFS on the DFA
graph
- * and adds new transitions to the given transitions DLL and marks states that
- * should be removed by setting state->contained to GNUNET_YES.
- *
- * @param dfa DFA for which the paths should be compressed.
- * @param start starting state for linear path search.
- * @param cur current state in the recursive DFS.
- * @param label current label (string of traversed labels).
- * @param max_len maximal path compression length.
- * @param transitions_head transitions DLL.
- * @param transitions_tail transitions DLL.
- */
-void
-dfa_compress_paths_helper (struct REGEX_ITERNAL_Automaton *dfa,
- struct REGEX_ITERNAL_State *start,
- struct REGEX_ITERNAL_State *cur, char *label,
- unsigned int max_len,
- struct REGEX_ITERNAL_Transition **transitions_head,
- struct REGEX_ITERNAL_Transition **transitions_tail)
-{
- struct REGEX_ITERNAL_Transition *t;
- char *new_label;
-
-
- if (NULL != label &&
- ((cur->incoming_transition_count > 1 || GNUNET_YES == cur->accepting ||
- GNUNET_YES == cur->marked) || (start != dfa->start && max_len > 0 &&
- max_len == strlen (label)) ||
- (start == dfa->start && GNUNET_REGEX_INITIAL_BYTES == strlen (label))))
- {
- t = GNUNET_malloc (sizeof (struct REGEX_ITERNAL_Transition));
- t->label = GNUNET_strdup (label);
- t->to_state = cur;
- t->from_state = start;
- GNUNET_CONTAINER_DLL_insert (*transitions_head, *transitions_tail, t);
-
- if (GNUNET_NO == cur->marked)
- {
- dfa_compress_paths_helper (dfa, cur, cur, NULL, max_len,
transitions_head,
- transitions_tail);
- }
- return;
- }
- else if (cur != start)
- cur->contained = GNUNET_YES;
-
- if (GNUNET_YES == cur->marked && cur != start)
- return;
-
- cur->marked = GNUNET_YES;
-
-
- for (t = cur->transitions_head; NULL != t; t = t->next)
- {
- if (NULL != label)
- GNUNET_asprintf (&new_label, "%s%s", label, t->label);
- else
- new_label = GNUNET_strdup (t->label);
-
- if (t->to_state != cur)
- {
- dfa_compress_paths_helper (dfa, start, t->to_state, new_label, max_len,
- transitions_head, transitions_tail);
- }
- GNUNET_free (new_label);
- }
-}
-
-
-/**
- * Compress paths in the given 'dfa'. Linear paths like 0->1->2->3 will be
- * compressed to 0->3 by combining transitions.
- *
- * @param regex_ctx context for adding new transitions.
- * @param dfa DFA representation, will directly modify the given DFA.
- * @param max_len maximal length of the compressed paths.
- */
-static void
-dfa_compress_paths (struct REGEX_ITERNAL_Context *regex_ctx,
- struct REGEX_ITERNAL_Automaton *dfa, unsigned int max_len)
-{
- struct REGEX_ITERNAL_State *s;
- struct REGEX_ITERNAL_State *s_next;
- struct REGEX_ITERNAL_Transition *t;
- struct REGEX_ITERNAL_Transition *t_next;
- struct REGEX_ITERNAL_Transition *transitions_head = NULL;
- struct REGEX_ITERNAL_Transition *transitions_tail = NULL;
-
- if (NULL == dfa)
- return;
-
- /* Count the incoming transitions on each state. */
- for (s = dfa->states_head; NULL != s; s = s->next)
- {
- for (t = s->transitions_head; NULL != t; t = t->next)
- {
- if (NULL != t->to_state)
- t->to_state->incoming_transition_count++;
- }
- }
-
- /* Unmark all states. */
- for (s = dfa->states_head; NULL != s; s = s->next)
- {
- s->marked = GNUNET_NO;
- s->contained = GNUNET_NO;
- }
-
- /* Add strides and mark states that can be deleted. */
- dfa_compress_paths_helper (dfa, dfa->start, dfa->start, NULL, max_len,
- &transitions_head, &transitions_tail);
-
- /* Add all the new transitions to the automaton. */
- for (t = transitions_head; NULL != t; t = t_next)
- {
- t_next = t->next;
- state_add_transition (regex_ctx, t->from_state, t->label, t->to_state);
- GNUNET_CONTAINER_DLL_remove (transitions_head, transitions_tail, t);
- GNUNET_free_non_null (t->label);
- GNUNET_free (t);
- }
-
- /* Remove marked states (including their incoming and outgoing transitions).
*/
- for (s = dfa->states_head; NULL != s; s = s_next)
- {
- s_next = s->next;
- if (GNUNET_YES == s->contained)
- automaton_remove_state (dfa, s);
- }
-}
-
-
-/**
- * Creates a new NFA fragment. Needs to be cleared using
- * automaton_fragment_clear.
- *
- * @param start starting state
- * @param end end state
- *
- * @return new NFA fragment
- */
-static struct REGEX_ITERNAL_Automaton *
-nfa_fragment_create (struct REGEX_ITERNAL_State *start,
- struct REGEX_ITERNAL_State *end)
-{
- struct REGEX_ITERNAL_Automaton *n;
-
- n = GNUNET_malloc (sizeof (struct REGEX_ITERNAL_Automaton));
-
- n->type = NFA;
- n->start = NULL;
- n->end = NULL;
- n->state_count = 0;
-
- if (NULL == start || NULL == end)
- return n;
-
- automaton_add_state (n, end);
- automaton_add_state (n, start);
-
- n->state_count = 2;
-
- n->start = start;
- n->end = end;
-
- return n;
-}
-
-
-/**
- * Adds a list of states to the given automaton 'n'.
- *
- * @param n automaton to which the states should be added
- * @param states_head head of the DLL of states
- * @param states_tail tail of the DLL of states
- */
-static void
-nfa_add_states (struct REGEX_ITERNAL_Automaton *n,
- struct REGEX_ITERNAL_State *states_head,
- struct REGEX_ITERNAL_State *states_tail)
-{
- struct REGEX_ITERNAL_State *s;
-
- if (NULL == n || NULL == states_head)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Could not add states\n");
- return;
- }
-
- if (NULL == n->states_head)
- {
- n->states_head = states_head;
- n->states_tail = states_tail;
- return;
- }
-
- if (NULL != states_head)
- {
- n->states_tail->next = states_head;
- n->states_tail = states_tail;
- }
-
- for (s = states_head; NULL != s; s = s->next)
- n->state_count++;
-}
-
-
-/**
- * Creates a new NFA state. Needs to be freed using automaton_destroy_state.
- *
- * @param ctx context
- * @param accepting is it an accepting state or not
- *
- * @return new NFA state
- */
-static struct REGEX_ITERNAL_State *
-nfa_state_create (struct REGEX_ITERNAL_Context *ctx, int accepting)
-{
- struct REGEX_ITERNAL_State *s;
-
- s = GNUNET_malloc (sizeof (struct REGEX_ITERNAL_State));
- s->id = ctx->state_id++;
- s->accepting = accepting;
- s->marked = GNUNET_NO;
- s->contained = 0;
- s->index = -1;
- s->lowlink = -1;
- s->scc_id = 0;
- s->name = NULL;
- GNUNET_asprintf (&s->name, "s%i", s->id);
-
- return s;
-}
-
-
-/**
- * Calculates the closure set for the given set of states.
- *
- * @param ret set to sorted nfa closure on 'label' (epsilon closure if 'label'
is NULL)
- * @param nfa the NFA containing 's'
- * @param states list of states on which to base the closure on
- * @param label transitioning label for which to base the closure on,
- * pass NULL for epsilon transition
- */
-static void
-nfa_closure_set_create (struct REGEX_ITERNAL_StateSet *ret,
- struct REGEX_ITERNAL_Automaton *nfa,
- struct REGEX_ITERNAL_StateSet *states, const char
*label)
-{
- struct REGEX_ITERNAL_State *s;
- unsigned int i;
- struct REGEX_ITERNAL_StateSet_MDLL cls_stack;
- struct REGEX_ITERNAL_State *clsstate;
- struct REGEX_ITERNAL_State *currentstate;
- struct REGEX_ITERNAL_Transition *ctran;
-
- memset (ret, 0, sizeof (struct REGEX_ITERNAL_StateSet));
- if (NULL == states)
- return;
-
- for (i = 0; i < states->off; i++)
- {
- s = states->states[i];
-
- /* Add start state to closure only for epsilon closure */
- if (NULL == label)
- state_set_append (ret, s);
-
- /* initialize work stack */
- cls_stack.head = NULL;
- cls_stack.tail = NULL;
- GNUNET_CONTAINER_MDLL_insert (ST, cls_stack.head, cls_stack.tail, s);
- cls_stack.len = 1;
-
- while (NULL != (currentstate = cls_stack.tail))
- {
- GNUNET_CONTAINER_MDLL_remove (ST, cls_stack.head, cls_stack.tail,
- currentstate);
- cls_stack.len--;
- for (ctran = currentstate->transitions_head; NULL != ctran;
- ctran = ctran->next)
- {
- if (NULL == (clsstate = ctran->to_state))
- continue;
- if (0 != clsstate->contained)
- continue;
- if (0 != nullstrcmp (label, ctran->label))
- continue;
- state_set_append (ret, clsstate);
- GNUNET_CONTAINER_MDLL_insert_tail (ST, cls_stack.head, cls_stack.tail,
- clsstate);
- cls_stack.len++;
- clsstate->contained = 1;
- }
- }
- }
- for (i = 0; i < ret->off; i++)
- ret->states[i]->contained = 0;
-
- if (ret->off > 1)
- qsort (ret->states, ret->off, sizeof (struct REGEX_ITERNAL_State *),
- &state_compare);
-}
-
-
-/**
- * Pops two NFA fragments (a, b) from the stack and concatenates them (ab)
- *
- * @param ctx context
- */
-static void
-nfa_add_concatenation (struct REGEX_ITERNAL_Context *ctx)
-{
- struct REGEX_ITERNAL_Automaton *a;
- struct REGEX_ITERNAL_Automaton *b;
- struct REGEX_ITERNAL_Automaton *new_nfa;
-
- b = ctx->stack_tail;
- GNUNET_assert (NULL != b);
- GNUNET_CONTAINER_DLL_remove (ctx->stack_head, ctx->stack_tail, b);
- a = ctx->stack_tail;
- GNUNET_assert (NULL != a);
- GNUNET_CONTAINER_DLL_remove (ctx->stack_head, ctx->stack_tail, a);
-
- state_add_transition (ctx, a->end, NULL, b->start);
- a->end->accepting = 0;
- b->end->accepting = 1;
-
- new_nfa = nfa_fragment_create (NULL, NULL);
- nfa_add_states (new_nfa, a->states_head, a->states_tail);
- nfa_add_states (new_nfa, b->states_head, b->states_tail);
- new_nfa->start = a->start;
- new_nfa->end = b->end;
- new_nfa->state_count += a->state_count + b->state_count;
- automaton_fragment_clear (a);
- automaton_fragment_clear (b);
-
- GNUNET_CONTAINER_DLL_insert_tail (ctx->stack_head, ctx->stack_tail, new_nfa);
-}
-
-
-/**
- * Pops a NFA fragment from the stack (a) and adds a new fragment (a*)
- *
- * @param ctx context
- */
-static void
-nfa_add_star_op (struct REGEX_ITERNAL_Context *ctx)
-{
- struct REGEX_ITERNAL_Automaton *a;
- struct REGEX_ITERNAL_Automaton *new_nfa;
- struct REGEX_ITERNAL_State *start;
- struct REGEX_ITERNAL_State *end;
-
- a = ctx->stack_tail;
-
- if (NULL == a)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "nfa_add_star_op failed, because there was no element on the
stack");
- return;
- }
-
- GNUNET_CONTAINER_DLL_remove (ctx->stack_head, ctx->stack_tail, a);
-
- start = nfa_state_create (ctx, 0);
- end = nfa_state_create (ctx, 1);
-
- state_add_transition (ctx, start, NULL, a->start);
- state_add_transition (ctx, start, NULL, end);
- state_add_transition (ctx, a->end, NULL, a->start);
- state_add_transition (ctx, a->end, NULL, end);
-
- a->end->accepting = 0;
- end->accepting = 1;
-
- new_nfa = nfa_fragment_create (start, end);
- nfa_add_states (new_nfa, a->states_head, a->states_tail);
- automaton_fragment_clear (a);
-
- GNUNET_CONTAINER_DLL_insert_tail (ctx->stack_head, ctx->stack_tail, new_nfa);
-}
-
-
-/**
- * Pops an NFA fragment (a) from the stack and adds a new fragment (a+)
- *
- * @param ctx context
- */
-static void
-nfa_add_plus_op (struct REGEX_ITERNAL_Context *ctx)
-{
- struct REGEX_ITERNAL_Automaton *a;
-
- a = ctx->stack_tail;
-
- if (NULL == a)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "nfa_add_plus_op failed, because there was no element on the
stack");
- return;
- }
-
- GNUNET_CONTAINER_DLL_remove (ctx->stack_head, ctx->stack_tail, a);
-
- state_add_transition (ctx, a->end, NULL, a->start);
-
- GNUNET_CONTAINER_DLL_insert_tail (ctx->stack_head, ctx->stack_tail, a);
-}
-
-
-/**
- * Pops an NFA fragment (a) from the stack and adds a new fragment (a?)
- *
- * @param ctx context
- */
-static void
-nfa_add_question_op (struct REGEX_ITERNAL_Context *ctx)
-{
- struct REGEX_ITERNAL_Automaton *a;
- struct REGEX_ITERNAL_Automaton *new_nfa;
- struct REGEX_ITERNAL_State *start;
- struct REGEX_ITERNAL_State *end;
-
- a = ctx->stack_tail;
-
- if (NULL == a)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "nfa_add_question_op failed, because there was no element on
the stack");
- return;
- }
-
- GNUNET_CONTAINER_DLL_remove (ctx->stack_head, ctx->stack_tail, a);
-
- start = nfa_state_create (ctx, 0);
- end = nfa_state_create (ctx, 1);
-
- state_add_transition (ctx, start, NULL, a->start);
- state_add_transition (ctx, start, NULL, end);
- state_add_transition (ctx, a->end, NULL, end);
-
- a->end->accepting = 0;
-
- new_nfa = nfa_fragment_create (start, end);
- nfa_add_states (new_nfa, a->states_head, a->states_tail);
- GNUNET_CONTAINER_DLL_insert_tail (ctx->stack_head, ctx->stack_tail, new_nfa);
- automaton_fragment_clear (a);
-}
-
-
-/**
- * Pops two NFA fragments (a, b) from the stack and adds a new NFA fragment
that
- * alternates between a and b (a|b)
- *
- * @param ctx context
- */
-static void
-nfa_add_alternation (struct REGEX_ITERNAL_Context *ctx)
-{
- struct REGEX_ITERNAL_Automaton *a;
- struct REGEX_ITERNAL_Automaton *b;
- struct REGEX_ITERNAL_Automaton *new_nfa;
- struct REGEX_ITERNAL_State *start;
- struct REGEX_ITERNAL_State *end;
-
- b = ctx->stack_tail;
- GNUNET_assert (NULL != b);
- GNUNET_CONTAINER_DLL_remove (ctx->stack_head, ctx->stack_tail, b);
- a = ctx->stack_tail;
- GNUNET_assert (NULL != a);
- GNUNET_CONTAINER_DLL_remove (ctx->stack_head, ctx->stack_tail, a);
-
- start = nfa_state_create (ctx, 0);
- end = nfa_state_create (ctx, 1);
- state_add_transition (ctx, start, NULL, a->start);
- state_add_transition (ctx, start, NULL, b->start);
-
- state_add_transition (ctx, a->end, NULL, end);
- state_add_transition (ctx, b->end, NULL, end);
-
- a->end->accepting = 0;
- b->end->accepting = 0;
- end->accepting = 1;
-
- new_nfa = nfa_fragment_create (start, end);
- nfa_add_states (new_nfa, a->states_head, a->states_tail);
- nfa_add_states (new_nfa, b->states_head, b->states_tail);
- automaton_fragment_clear (a);
- automaton_fragment_clear (b);
-
- GNUNET_CONTAINER_DLL_insert_tail (ctx->stack_head, ctx->stack_tail, new_nfa);
-}
-
-
-/**
- * Adds a new nfa fragment to the stack
- *
- * @param ctx context
- * @param label label for nfa transition
- */
-static void
-nfa_add_label (struct REGEX_ITERNAL_Context *ctx, const char *label)
-{
- struct REGEX_ITERNAL_Automaton *n;
- struct REGEX_ITERNAL_State *start;
- struct REGEX_ITERNAL_State *end;
-
- GNUNET_assert (NULL != ctx);
-
- start = nfa_state_create (ctx, 0);
- end = nfa_state_create (ctx, 1);
- state_add_transition (ctx, start, label, end);
- n = nfa_fragment_create (start, end);
- GNUNET_assert (NULL != n);
- GNUNET_CONTAINER_DLL_insert_tail (ctx->stack_head, ctx->stack_tail, n);
-}
-
-
-/**
- * Initialize a new context
- *
- * @param ctx context
- */
-static void
-REGEX_ITERNAL_context_init (struct REGEX_ITERNAL_Context *ctx)
-{
- if (NULL == ctx)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Context was NULL!");
- return;
- }
- ctx->state_id = 0;
- ctx->transition_id = 0;
- ctx->stack_head = NULL;
- ctx->stack_tail = NULL;
-}
-
-
-/**
- * Construct an NFA by parsing the regex string of length 'len'.
- *
- * @param regex regular expression string
- * @param len length of the string
- *
- * @return NFA, needs to be freed using REGEX_ITERNAL_destroy_automaton
- */
-struct REGEX_ITERNAL_Automaton *
-REGEX_ITERNAL_construct_nfa (const char *regex, const size_t len)
-{
- struct REGEX_ITERNAL_Context ctx;
- struct REGEX_ITERNAL_Automaton *nfa;
- const char *regexp;
- char curlabel[2];
- char *error_msg;
- unsigned int count;
- unsigned int altcount;
- unsigned int atomcount;
- unsigned int poff;
- unsigned int psize;
- struct
- {
- int altcount;
- int atomcount;
- } *p;
-
- if (NULL == regex || 0 == strlen (regex) || 0 == len)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "Could not parse regex. Empty regex string provided.\n");
-
- return NULL;
- }
- REGEX_ITERNAL_context_init (&ctx);
-
- regexp = regex;
- curlabel[1] = '\0';
- p = NULL;
- error_msg = NULL;
- altcount = 0;
- atomcount = 0;
- poff = 0;
- psize = 0;
-
- for (count = 0; count < len && *regexp; count++, regexp++)
- {
- switch (*regexp)
- {
- case '(':
- if (atomcount > 1)
- {
- --atomcount;
- nfa_add_concatenation (&ctx);
- }
- if (poff == psize)
- GNUNET_array_grow (p, psize, psize * 2 + 4);
- p[poff].altcount = altcount;
- p[poff].atomcount = atomcount;
- poff++;
- altcount = 0;
- atomcount = 0;
- break;
- case '|':
- if (0 == atomcount)
- {
- error_msg = "Cannot append '|' to nothing";
- goto error;
- }
- while (--atomcount > 0)
- nfa_add_concatenation (&ctx);
- altcount++;
- break;
- case ')':
- if (0 == poff)
- {
- error_msg = "Missing opening '('";
- goto error;
- }
- if (0 == atomcount)
- {
- /* Ignore this: "()" */
- poff--;
- altcount = p[poff].altcount;
- atomcount = p[poff].atomcount;
- break;
- }
- while (--atomcount > 0)
- nfa_add_concatenation (&ctx);
- for (; altcount > 0; altcount--)
- nfa_add_alternation (&ctx);
- poff--;
- altcount = p[poff].altcount;
- atomcount = p[poff].atomcount;
- atomcount++;
- break;
- case '*':
- if (atomcount == 0)
- {
- error_msg = "Cannot append '*' to nothing";
- goto error;
- }
- nfa_add_star_op (&ctx);
- break;
- case '+':
- if (atomcount == 0)
- {
- error_msg = "Cannot append '+' to nothing";
- goto error;
- }
- nfa_add_plus_op (&ctx);
- break;
- case '?':
- if (atomcount == 0)
- {
- error_msg = "Cannot append '?' to nothing";
- goto error;
- }
- nfa_add_question_op (&ctx);
- break;
- default:
- if (atomcount > 1)
- {
- --atomcount;
- nfa_add_concatenation (&ctx);
- }
- curlabel[0] = *regexp;
- nfa_add_label (&ctx, curlabel);
- atomcount++;
- break;
- }
- }
- if (0 != poff)
- {
- error_msg = "Unbalanced parenthesis";
- goto error;
- }
- while (--atomcount > 0)
- nfa_add_concatenation (&ctx);
- for (; altcount > 0; altcount--)
- nfa_add_alternation (&ctx);
-
- GNUNET_array_grow (p, psize, 0);
-
- nfa = ctx.stack_tail;
- GNUNET_CONTAINER_DLL_remove (ctx.stack_head, ctx.stack_tail, nfa);
-
- if (NULL != ctx.stack_head)
- {
- error_msg = "Creating the NFA failed. NFA stack was not empty!";
- goto error;
- }
-
- /* Remember the regex that was used to generate this NFA */
- nfa->regex = GNUNET_strdup (regex);
-
- /* create depth-first numbering of the states for pretty printing */
- REGEX_ITERNAL_automaton_traverse (nfa, NULL, NULL, NULL, &number_states,
NULL);
-
- /* No multistriding added so far */
- nfa->is_multistrided = GNUNET_NO;
-
- return nfa;
-
-error:
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Could not parse regex: `%s'\n", regex);
- if (NULL != error_msg)
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "%s\n", error_msg);
-
- GNUNET_free_non_null (p);
-
- while (NULL != (nfa = ctx.stack_head))
- {
- GNUNET_CONTAINER_DLL_remove (ctx.stack_head, ctx.stack_tail, nfa);
- REGEX_ITERNAL_automaton_destroy (nfa);
- }
-
- return NULL;
-}
-
-
-/**
- * Create DFA states based on given 'nfa' and starting with 'dfa_state'.
- *
- * @param ctx context.
- * @param nfa NFA automaton.
- * @param dfa DFA automaton.
- * @param dfa_state current dfa state, pass epsilon closure of first nfa state
- * for starting.
- */
-static void
-construct_dfa_states (struct REGEX_ITERNAL_Context *ctx,
- struct REGEX_ITERNAL_Automaton *nfa,
- struct REGEX_ITERNAL_Automaton *dfa,
- struct REGEX_ITERNAL_State *dfa_state)
-{
- struct REGEX_ITERNAL_Transition *ctran;
- struct REGEX_ITERNAL_State *new_dfa_state;
- struct REGEX_ITERNAL_State *state_contains;
- struct REGEX_ITERNAL_State *state_iter;
- struct REGEX_ITERNAL_StateSet tmp;
- struct REGEX_ITERNAL_StateSet nfa_set;
-
- for (ctran = dfa_state->transitions_head; NULL != ctran; ctran = ctran->next)
- {
- if (NULL == ctran->label || NULL != ctran->to_state)
- continue;
-
- nfa_closure_set_create (&tmp, nfa, &dfa_state->nfa_set, ctran->label);
- nfa_closure_set_create (&nfa_set, nfa, &tmp, NULL);
- state_set_clear (&tmp);
-
- state_contains = NULL;
- for (state_iter = dfa->states_head; NULL != state_iter;
- state_iter = state_iter->next)
- {
- if (0 == state_set_compare (&state_iter->nfa_set, &nfa_set))
- {
- state_contains = state_iter;
- break;
- }
- }
- if (NULL == state_contains)
- {
- new_dfa_state = dfa_state_create (ctx, &nfa_set);
- automaton_add_state (dfa, new_dfa_state);
- ctran->to_state = new_dfa_state;
- construct_dfa_states (ctx, nfa, dfa, new_dfa_state);
- }
- else
- {
- ctran->to_state = state_contains;
- state_set_clear (&nfa_set);
- }
- }
-}
-
-
-/**
- * Construct DFA for the given 'regex' of length 'len'.
- *
- * Path compression means, that for example a DFA o -> a -> b -> c -> o will be
- * compressed to o -> abc -> o. Note that this parameter influences the
- * non-determinism of states of the resulting NFA in the DHT (number of
outgoing
- * edges with the same label). For example for an application that stores IPv4
- * addresses as bitstrings it could make sense to limit the path compression to
- * 4 or 8.
- *
- * @param regex regular expression string.
- * @param len length of the regular expression.
- * @param max_path_len limit the path compression length to the
- * given value. If set to 1, no path compression is applied. Set to 0
for
- * maximal possible path compression (generally not desireable).
- * @return DFA, needs to be freed using REGEX_ITERNAL_automaton_destroy.
- */
-struct REGEX_ITERNAL_Automaton *
-REGEX_ITERNAL_construct_dfa (const char *regex, const size_t len,
- unsigned int max_path_len)
-{
- struct REGEX_ITERNAL_Context ctx;
- struct REGEX_ITERNAL_Automaton *dfa;
- struct REGEX_ITERNAL_Automaton *nfa;
- struct REGEX_ITERNAL_StateSet nfa_start_eps_cls;
- struct REGEX_ITERNAL_StateSet singleton_set;
-
- REGEX_ITERNAL_context_init (&ctx);
-
- /* Create NFA */
- // fprintf (stderr, "N");
- nfa = REGEX_ITERNAL_construct_nfa (regex, len);
-
- if (NULL == nfa)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "Could not create DFA, because NFA creation failed\n");
- return NULL;
- }
-
- dfa = GNUNET_malloc (sizeof (struct REGEX_ITERNAL_Automaton));
- dfa->type = DFA;
- dfa->regex = GNUNET_strdup (regex);
-
- /* Create DFA start state from epsilon closure */
- memset (&singleton_set, 0, sizeof (struct REGEX_ITERNAL_StateSet));
- state_set_append (&singleton_set, nfa->start);
- nfa_closure_set_create (&nfa_start_eps_cls, nfa, &singleton_set, NULL);
- state_set_clear (&singleton_set);
- dfa->start = dfa_state_create (&ctx, &nfa_start_eps_cls);
- automaton_add_state (dfa, dfa->start);
-
- // fprintf (stderr, "D");
- construct_dfa_states (&ctx, nfa, dfa, dfa->start);
- REGEX_ITERNAL_automaton_destroy (nfa);
-
- /* Minimize DFA */
- // fprintf (stderr, "M");
- if (GNUNET_OK != dfa_minimize (&ctx, dfa))
- {
- REGEX_ITERNAL_automaton_destroy (dfa);
- return NULL;
- }
-
- /* Create proofs and hashes for all states */
- if (GNUNET_OK != automaton_create_proofs (dfa))
- {
- REGEX_ITERNAL_automaton_destroy (dfa);
- return NULL;
- }
-
- /* Compress linear DFA paths */
- if (1 != max_path_len)
- dfa_compress_paths (&ctx, dfa, max_path_len);
-
- return dfa;
-}
-
-
-/**
- * Free the memory allocated by constructing the REGEX_ITERNAL_Automaton data
- * structure.
- *
- * @param a automaton to be destroyed
- */
-void
-REGEX_ITERNAL_automaton_destroy (struct REGEX_ITERNAL_Automaton *a)
-{
- struct REGEX_ITERNAL_State *s;
- struct REGEX_ITERNAL_State *next_state;
-
- if (NULL == a)
- return;
-
- GNUNET_free_non_null (a->regex);
- GNUNET_free_non_null (a->canonical_regex);
-
- for (s = a->states_head; NULL != s; s = next_state)
- {
- next_state = s->next;
- GNUNET_CONTAINER_DLL_remove (a->states_head, a->states_tail, s);
- automaton_destroy_state (s);
- }
-
- GNUNET_free (a);
-}
-
-
-/**
- * Evaluates the given string using the given DFA automaton
- *
- * @param a automaton, type must be DFA
- * @param string string that should be evaluated
- *
- * @return 0 if string matches, non 0 otherwise
- */
-static int
-evaluate_dfa (struct REGEX_ITERNAL_Automaton *a, const char *string)
-{
- const char *strp;
- struct REGEX_ITERNAL_State *s;
- unsigned int step_len;
-
- if (DFA != a->type)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "Tried to evaluate DFA, but NFA automaton given");
- return -1;
- }
-
- s = a->start;
-
- /* If the string is empty but the starting state is accepting, we accept. */
- if ((NULL == string || 0 == strlen (string)) && s->accepting)
- return 0;
-
- for (strp = string; NULL != strp && *strp; strp += step_len)
- {
- step_len = dfa_move (&s, strp);
-
- if (NULL == s)
- break;
- }
-
- if (NULL != s && s->accepting)
- return 0;
-
- return 1;
-}
-
-
-/**
- * Evaluates the given string using the given NFA automaton
- *
- * @param a automaton, type must be NFA
- * @param string string that should be evaluated
- *
- * @return 0 if string matches, non 0 otherwise
- */
-static int
-evaluate_nfa (struct REGEX_ITERNAL_Automaton *a, const char *string)
-{
- const char *strp;
- char str[2];
- struct REGEX_ITERNAL_State *s;
- struct REGEX_ITERNAL_StateSet sset;
- struct REGEX_ITERNAL_StateSet new_sset;
- struct REGEX_ITERNAL_StateSet singleton_set;
- unsigned int i;
- int result;
-
- if (NFA != a->type)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "Tried to evaluate NFA, but DFA automaton given");
- return -1;
- }
-
- /* If the string is empty but the starting state is accepting, we accept. */
- if ((NULL == string || 0 == strlen (string)) && a->start->accepting)
- return 0;
-
- result = 1;
- memset (&singleton_set, 0, sizeof (struct REGEX_ITERNAL_StateSet));
- state_set_append (&singleton_set, a->start);
- nfa_closure_set_create (&sset, a, &singleton_set, NULL);
- state_set_clear (&singleton_set);
-
- str[1] = '\0';
- for (strp = string; NULL != strp && *strp; strp++)
- {
- str[0] = *strp;
- nfa_closure_set_create (&new_sset, a, &sset, str);
- state_set_clear (&sset);
- nfa_closure_set_create (&sset, a, &new_sset, 0);
- state_set_clear (&new_sset);
- }
-
- for (i = 0; i < sset.off; i++)
- {
- s = sset.states[i];
- if ( (NULL != s) && (s->accepting) )
- {
- result = 0;
- break;
- }
- }
-
- state_set_clear (&sset);
- return result;
-}
-
-
-/**
- * Evaluates the given 'string' against the given compiled regex
- *
- * @param a automaton
- * @param string string to check
- *
- * @return 0 if string matches, non 0 otherwise
- */
-int
-REGEX_ITERNAL_eval (struct REGEX_ITERNAL_Automaton *a, const char *string)
-{
- int result;
-
- switch (a->type)
- {
- case DFA:
- result = evaluate_dfa (a, string);
- break;
- case NFA:
- result = evaluate_nfa (a, string);
- break;
- default:
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "Evaluating regex failed, automaton has no type!\n");
- result = GNUNET_SYSERR;
- break;
- }
-
- return result;
-}
-
-
-/**
- * Get the canonical regex of the given automaton.
- * When constructing the automaton a proof is computed for each state,
- * consisting of the regular expression leading to this state. A complete
- * regex for the automaton can be computed by combining these proofs.
- * As of now this function is only useful for testing.
- *
- * @param a automaton for which the canonical regex should be returned.
- *
- * @return
- */
-const char *
-REGEX_ITERNAL_get_canonical_regex (struct REGEX_ITERNAL_Automaton *a)
-{
- if (NULL == a)
- return NULL;
-
- return a->canonical_regex;
-}
-
-
-/**
- * Get the number of transitions that are contained in the given automaton.
- *
- * @param a automaton for which the number of transitions should be returned.
- *
- * @return number of transitions in the given automaton.
- */
-unsigned int
-REGEX_ITERNAL_get_transition_count (struct REGEX_ITERNAL_Automaton *a)
-{
- unsigned int t_count;
- struct REGEX_ITERNAL_State *s;
-
- if (NULL == a)
- return 0;
-
- t_count = 0;
- for (s = a->states_head; NULL != s; s = s->next)
- t_count += s->transition_count;
-
- return t_count;
-}
-
-
-/**
- * Get the first key for the given 'input_string'. This hashes the first x bits
- * of the 'input_string'.
- *
- * @param input_string string.
- * @param string_len length of the 'input_string'.
- * @param key pointer to where to write the hash code.
- *
- * @return number of bits of 'input_string' that have been consumed
- * to construct the key
- */
-size_t
-REGEX_ITERNAL_get_first_key (const char *input_string, size_t string_len,
- struct GNUNET_HashCode * key)
-{
- unsigned int size;
-
- size =
- string_len <
- GNUNET_REGEX_INITIAL_BYTES ? string_len : GNUNET_REGEX_INITIAL_BYTES;
-
- if (NULL == input_string)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Given input string was NULL!\n");
- return 0;
- }
-
- GNUNET_CRYPTO_hash (input_string, size, key);
-
- return size;
-}
-
-
-/**
- * Check if the given 'proof' matches the given 'key'.
- *
- * @param proof partial regex of a state.
- * @param key hash of a state.
- *
- * @return GNUNET_OK if the proof is valid for the given key.
- */
-int
-REGEX_ITERNAL_check_proof (const char *proof, const struct GNUNET_HashCode
*key)
-{
- struct GNUNET_HashCode key_check;
-
- if (NULL == proof || NULL == key)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Proof check failed, was NULL.\n");
- return GNUNET_NO;
- }
-
- GNUNET_CRYPTO_hash (proof, strlen (proof), &key_check);
- return (0 ==
- GNUNET_CRYPTO_hash_cmp (key, &key_check)) ? GNUNET_OK : GNUNET_NO;
-}
-
-
-/**
- * Recursive function that calls the iterator for each synthetic start state.
- *
- * @param min_len minimum length of the path in the graph.
- * @param max_len maximum length of the path in the graph.
- * @param consumed_string string consumed by traversing the graph till this
state.
- * @param state current state of the automaton.
- * @param iterator iterator function called for each edge.
- * @param iterator_cls closure for the iterator function.
- */
-static void
-iterate_initial_edge (const unsigned int min_len, const unsigned int max_len,
- char *consumed_string, struct REGEX_ITERNAL_State *state,
- REGEX_ITERNAL_KeyIterator iterator, void *iterator_cls)
-{
- unsigned int i;
- char *temp;
- struct REGEX_ITERNAL_Transition *t;
- unsigned int num_edges = state->transition_count;
- struct REGEX_ITERNAL_Edge edges[num_edges];
- struct REGEX_ITERNAL_Edge edge[1];
- struct GNUNET_HashCode hash;
- struct GNUNET_HashCode hash_new;
-
- unsigned int cur_len;
-
- if (NULL != consumed_string)
- cur_len = strlen (consumed_string);
- else
- cur_len = 0;
-
- if ((cur_len >= min_len || GNUNET_YES == state->accepting) && cur_len > 0 &&
- NULL != consumed_string)
- {
- if (cur_len <= max_len)
- {
- if (state->proof != NULL && 0 != strcmp (consumed_string, state->proof))
- {
- for (i = 0, t = state->transitions_head; NULL != t && i < num_edges;
- t = t->next, i++)
- {
- edges[i].label = t->label;
- edges[i].destination = t->to_state->hash;
- }
- GNUNET_CRYPTO_hash (consumed_string, strlen (consumed_string), &hash);
- iterator (iterator_cls, &hash, consumed_string, state->accepting,
- num_edges, edges);
- }
-
- if (GNUNET_YES == state->accepting && cur_len > 1 &&
- state->transition_count < 1 && cur_len < max_len)
- {
- /* Special case for regex consisting of just a string that is shorter
than
- * max_len */
- edge[0].label = &consumed_string[cur_len - 1];
- edge[0].destination = state->hash;
- temp = GNUNET_strdup (consumed_string);
- temp[cur_len - 1] = '\0';
- GNUNET_CRYPTO_hash (temp, cur_len - 1, &hash_new);
- iterator (iterator_cls, &hash_new, temp, GNUNET_NO, 1, edge);
- GNUNET_free (temp);
- }
- }
- else if (max_len < cur_len)
- {
- /* Case where the concatenated labels are longer than max_len, then
split. */
- edge[0].label = &consumed_string[max_len];
- edge[0].destination = state->hash;
- temp = GNUNET_strdup (consumed_string);
- temp[max_len] = '\0';
- GNUNET_CRYPTO_hash (temp, max_len, &hash);
- iterator (iterator_cls, &hash, temp, GNUNET_NO, 1, edge);
- GNUNET_free (temp);
- }
- }
-
- if (cur_len < max_len)
- {
- for (t = state->transitions_head; NULL != t; t = t->next)
- {
- if (NULL != consumed_string)
- GNUNET_asprintf (&temp, "%s%s", consumed_string, t->label);
- else
- GNUNET_asprintf (&temp, "%s", t->label);
-
- iterate_initial_edge (min_len, max_len, temp, t->to_state, iterator,
- iterator_cls);
- GNUNET_free (temp);
- }
- }
-}
-
-
-/**
- * Iterate over all edges starting from start state of automaton 'a'. Calling
- * iterator for each edge.
- *
- * @param a automaton.
- * @param iterator iterator called for each edge.
- * @param iterator_cls closure.
- */
-void
-REGEX_ITERNAL_iterate_all_edges (struct REGEX_ITERNAL_Automaton *a,
- REGEX_ITERNAL_KeyIterator iterator,
- void *iterator_cls)
-{
- struct REGEX_ITERNAL_State *s;
-
- for (s = a->states_head; NULL != s; s = s->next)
- {
- struct REGEX_ITERNAL_Edge edges[s->transition_count];
- unsigned int num_edges;
-
- num_edges = state_get_edges (s, edges);
-
- if ((NULL != s->proof && 0 < strlen (s->proof)) || s->accepting)
- iterator (iterator_cls, &s->hash, s->proof, s->accepting, num_edges,
- edges);
-
- s->marked = GNUNET_NO;
- }
-
- iterate_initial_edge (GNUNET_REGEX_INITIAL_BYTES, GNUNET_REGEX_INITIAL_BYTES,
- NULL, a->start, iterator, iterator_cls);
-}
-
-
-
-
-/* end of regex.c */
Deleted: gnunet/src/regex/regex_dht.c
===================================================================
--- gnunet/src/regex/regex_dht.c 2013-06-20 08:32:50 UTC (rev 27498)
+++ gnunet/src/regex/regex_dht.c 2013-06-20 08:55:56 UTC (rev 27499)
@@ -1,814 +0,0 @@
-/*
- This file is part of GNUnet
- (C) 2012 Christian Grothoff (and other contributing authors)
-
- GNUnet is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published
- by the Free Software Foundation; either version 3, or (at your
- option) any later version.
-
- GNUnet is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with GNUnet; see the file COPYING. If not, write to the
- Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA.
-*/
-/**
- * @file src/regex/regex_dht.c
- * @brief library to announce regexes in the network and match strings
- * against published regexes.
- * @author Bartlomiej Polot
- */
-#include "platform.h"
-#include "regex_internal_lib.h"
-#include "regex_block_lib.h"
-#include "gnunet_dht_service.h"
-#include "gnunet_statistics_service.h"
-
-#define LOG(kind,...) GNUNET_log_from (kind,"regex-dht",__VA_ARGS__)
-
-/* FIXME: OPTION (API, CONFIG) */
-#define DHT_REPLICATION 5
-#define DHT_TTL GNUNET_TIME_UNIT_HOURS
-#define DEBUG_DHT GNUNET_NO
-
-#if DEBUG_DHT
-#define DHT_OPT GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE |
GNUNET_DHT_RO_RECORD_ROUTE
-#else
-#define DHT_OPT GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE
-#endif
-
-struct REGEX_ITERNAL_Announcement
-{
- /**
- * DHT handle to use, must be initialized externally.
- */
- struct GNUNET_DHT_Handle *dht;
-
- /**
- * Regular expression.
- */
- const char *regex;
-
- /**
- * Automaton representation of the regex (expensive to build).
- */
- struct REGEX_ITERNAL_Automaton* dfa;
-
- /**
- * Identity under which to announce the regex.
- */
- struct GNUNET_PeerIdentity id;
-
- /**
- * Optional statistics handle to report usage. Can be NULL.
- */
- struct GNUNET_STATISTICS_Handle *stats;
-};
-
-
-/**
- * Regex callback iterator to store own service description in the DHT.
- *
- * @param cls closure.
- * @param key hash for current state.
- * @param proof proof for current state.
- * @param accepting GNUNET_YES if this is an accepting state, GNUNET_NO if not.
- * @param num_edges number of edges leaving current state.
- * @param edges edges leaving current state.
- */
-static void
-regex_iterator (void *cls,
- const struct GNUNET_HashCode *key,
- const char *proof,
- int accepting,
- unsigned int num_edges,
- const struct REGEX_ITERNAL_Edge *edges)
-{
- struct REGEX_ITERNAL_Announcement *h = cls;
- struct RegexBlock *block;
- struct RegexEdge *block_edge;
- size_t size;
- size_t len;
- unsigned int i;
- unsigned int offset;
- char *aux;
-
- LOG (GNUNET_ERROR_TYPE_DEBUG,
- " regex dht put for state %s\n",
- GNUNET_h2s (key));
- LOG (GNUNET_ERROR_TYPE_DEBUG, " proof: %s\n", proof);
- LOG (GNUNET_ERROR_TYPE_DEBUG, " num edges: %u\n", num_edges);
-
- if (GNUNET_YES == accepting)
- {
- struct RegexAccept block;
-
- LOG (GNUNET_ERROR_TYPE_DEBUG,
- " state %s is accepting, putting own id\n",
- GNUNET_h2s(key));
- size = sizeof (block);
- block.key = *key;
- block.id = h->id;
- GNUNET_STATISTICS_update (h->stats, "# regex accepting blocks stored",
- 1, GNUNET_NO);
- GNUNET_STATISTICS_update (h->stats, "# regex accepting block bytes stored",
- sizeof (block), GNUNET_NO);
- (void)
- GNUNET_DHT_put (h->dht, key,
- DHT_REPLICATION,
- DHT_OPT | GNUNET_DHT_RO_RECORD_ROUTE,
- GNUNET_BLOCK_TYPE_REGEX_ACCEPT,
- size,
- (char *) &block,
- GNUNET_TIME_relative_to_absolute (DHT_TTL),
- DHT_TTL,
- NULL, NULL);
- }
- len = strlen(proof);
- size = sizeof (struct RegexBlock) + len;
- block = GNUNET_malloc (size);
-
- block->key = *key;
- block->n_proof = htonl (len);
- block->n_edges = htonl (num_edges);
- block->accepting = htonl (accepting);
-
- /* Store the proof at the end of the block. */
- aux = (char *) &block[1];
- memcpy (aux, proof, len);
- aux = &aux[len];
-
- /* Store each edge in a variable length MeshEdge struct at the
- * very end of the MeshRegexBlock structure.
- */
- for (i = 0; i < num_edges; i++)
- {
- LOG (GNUNET_ERROR_TYPE_DEBUG, " edge %s towards %s\n",
- edges[i].label, GNUNET_h2s(&edges[i].destination));
-
- /* aux points at the end of the last block */
- len = strlen (edges[i].label);
- size += sizeof (struct RegexEdge) + len;
- // Calculate offset FIXME is this ok? use size instead?
- offset = aux - (char *) block;
- block = GNUNET_realloc (block, size);
- aux = &((char *) block)[offset];
- block_edge = (struct RegexEdge *) aux;
- block_edge->key = edges[i].destination;
- block_edge->n_token = htonl (len);
- aux = (char *) &block_edge[1];
- memcpy (aux, edges[i].label, len);
- aux = &aux[len];
- }
- (void)
- GNUNET_DHT_put (h->dht, key,
- DHT_REPLICATION,
- DHT_OPT,
- GNUNET_BLOCK_TYPE_REGEX, size,
- (char *) block,
- GNUNET_TIME_relative_to_absolute (DHT_TTL),
- DHT_TTL,
- NULL, NULL);
- GNUNET_STATISTICS_update (h->stats, "# regex blocks stored",
- 1, GNUNET_NO);
- GNUNET_STATISTICS_update (h->stats, "# regex block bytes stored",
- size, GNUNET_NO);
- GNUNET_free (block);
-}
-
-
-struct REGEX_ITERNAL_Announcement *
-REGEX_ITERNAL_announce (struct GNUNET_DHT_Handle *dht,
- const struct GNUNET_PeerIdentity *id,
- const char *regex,
- uint16_t compression,
- struct GNUNET_STATISTICS_Handle *stats)
-{
- struct REGEX_ITERNAL_Announcement *h;
-
- GNUNET_assert (NULL != dht);
- h = GNUNET_malloc (sizeof (struct REGEX_ITERNAL_Announcement));
- h->regex = regex;
- h->dht = dht;
- h->stats = stats;
- h->id = *id;
- h->dfa = REGEX_ITERNAL_construct_dfa (regex,
- strlen (regex),
- compression);
- REGEX_ITERNAL_reannounce (h);
- return h;
-}
-
-void
-REGEX_ITERNAL_reannounce (struct REGEX_ITERNAL_Announcement *h)
-{
- GNUNET_assert (NULL != h->dfa); /* make sure to call announce first */
- LOG (GNUNET_ERROR_TYPE_INFO, "REGEX_ITERNAL_reannounce: %.60s\n", h->regex);
- LOG (GNUNET_ERROR_TYPE_DEBUG, " full: %s\n", h->regex);
- REGEX_ITERNAL_iterate_all_edges (h->dfa, ®ex_iterator, h);
-}
-
-void
-REGEX_ITERNAL_announce_cancel (struct REGEX_ITERNAL_Announcement *h)
-{
- REGEX_ITERNAL_automaton_destroy (h->dfa);
- GNUNET_free (h);
-}
-
-
-/******************************************************************************/
-
-
-/**
- * Struct to keep state of running searches that have consumed a part of
- * the inital string.
- */
-struct RegexSearchContext
-{
- /**
- * Part of the description already consumed by
- * this particular search branch.
- */
- size_t position;
-
- /**
- * Information about the search.
- */
- struct REGEX_ITERNAL_Search *info;
-
- /**
- * We just want to look for one edge, the longer the better.
- * Keep its length.
- */
- unsigned int longest_match;
-
- /**
- * Destination hash of the longest match.
- */
- struct GNUNET_HashCode hash;
-};
-
-
-/**
- * Struct to keep information of searches of services described by a regex
- * using a user-provided string service description.
- */
-struct REGEX_ITERNAL_Search
-{
- /**
- * DHT handle to use, must be initialized externally.
- */
- struct GNUNET_DHT_Handle *dht;
-
- /**
- * Optional statistics handle to report usage. Can be NULL.
- */
- struct GNUNET_STATISTICS_Handle *stats;
-
- /**
- * User provided description of the searched service.
- */
- char *description;
-
- /**
- * Running DHT GETs.
- */
- struct GNUNET_CONTAINER_MultiHashMap *dht_get_handles;
-
- /**
- * Results from running DHT GETs.
- */
- struct GNUNET_CONTAINER_MultiHashMap *dht_get_results;
-
- /**
- * Contexts, for each running DHT GET. Free all on end of search.
- */
- struct RegexSearchContext **contexts;
-
- /**
- * Number of contexts (branches/steps in search).
- */
- unsigned int n_contexts;
-
- /**
- * @param callback Callback for found peers.
- */
- REGEX_ITERNAL_Found callback;
-
- /**
- * @param callback_cls Closure for @c callback.
- */
- void *callback_cls;
-};
-
-
-
-/**
- * Jump to the next edge, with the longest matching token.
- *
- * @param block Block found in the DHT.
- * @param size Size of the block.
- * @param ctx Context of the search.
- *
- * @return GNUNET_YES if should keep iterating, GNUNET_NO otherwise.
- */
-static void
-regex_next_edge (const struct RegexBlock *block,
- size_t size,
- struct RegexSearchContext *ctx);
-
-
-/**
- * Function to process DHT string to regex matching.
- * Called on each result obtained for the DHT search.
- *
- * @param cls Closure (search context).
- * @param exp When will this value expire.
- * @param key Key of the result.
- * @param get_path Path of the get request.
- * @param get_path_length Lenght of get_path.
- * @param put_path Path of the put request.
- * @param put_path_length Length of the put_path.
- * @param type Type of the result.
- * @param size Number of bytes in data.
- * @param data Pointer to the result data.
- */
-static void
-dht_get_string_accept_handler (void *cls, struct GNUNET_TIME_Absolute exp,
- const struct GNUNET_HashCode * key,
- const struct GNUNET_PeerIdentity *get_path,
- unsigned int get_path_length,
- const struct GNUNET_PeerIdentity *put_path,
- unsigned int put_path_length,
- enum GNUNET_BLOCK_Type type,
- size_t size, const void *data)
-{
- const struct RegexAccept *block = data;
- struct RegexSearchContext *ctx = cls;
- struct REGEX_ITERNAL_Search *info = ctx->info;
-
- LOG (GNUNET_ERROR_TYPE_DEBUG, "Got regex results from DHT!\n");
- LOG (GNUNET_ERROR_TYPE_INFO, " accept for %s (key %s)\n",
- info->description, GNUNET_h2s(key));
-
- GNUNET_STATISTICS_update (info->stats, "# regex accepting blocks found",
- 1, GNUNET_NO);
- GNUNET_STATISTICS_update (info->stats, "# regex accepting block bytes found",
- size, GNUNET_NO);
-
- info->callback (info->callback_cls,
- &block->id,
- get_path, get_path_length,
- put_path, put_path_length);
-
- return;
-}
-
-/**
- * Find a path to a peer that offers a regex servcie compatible
- * with a given string.
- *
- * @param key The key of the accepting state.
- * @param ctx Context containing info about the string, tunnel, etc.
- */
-static void
-regex_find_path (const struct GNUNET_HashCode *key,
- struct RegexSearchContext *ctx)
-{
- struct GNUNET_DHT_GetHandle *get_h;
-
- LOG (GNUNET_ERROR_TYPE_DEBUG, "Found peer by service\n");
- LOG (GNUNET_ERROR_TYPE_INFO, " find accept for %s\n", GNUNET_h2s (key));
- get_h = GNUNET_DHT_get_start (ctx->info->dht, /* handle */
- GNUNET_BLOCK_TYPE_REGEX_ACCEPT, /* type */
- key, /* key to search */
- DHT_REPLICATION, /* replication level */
- DHT_OPT | GNUNET_DHT_RO_RECORD_ROUTE,
- NULL, /* xquery */ // FIXME BLOOMFILTER
- 0, /* xquery bits */ // FIXME BLOOMFILTER
SIZE
- &dht_get_string_accept_handler, ctx);
- GNUNET_break (GNUNET_OK ==
- GNUNET_CONTAINER_multihashmap_put(ctx->info->dht_get_handles,
- key,
- get_h,
-
GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE));
-}
-
-
-/**
- * Function to process DHT string to regex matching.
- * Called on each result obtained for the DHT search.
- *
- * @param cls closure (search context)
- * @param exp when will this value expire
- * @param key key of the result
- * @param get_path path of the get request (not used)
- * @param get_path_length lenght of get_path (not used)
- * @param put_path path of the put request (not used)
- * @param put_path_length length of the put_path (not used)
- * @param type type of the result
- * @param size number of bytes in data
- * @param data pointer to the result data
- *
- * TODO: re-issue the request after certain time? cancel after X results?
- */
-static void
-dht_get_string_handler (void *cls, struct GNUNET_TIME_Absolute exp,
- const struct GNUNET_HashCode * key,
- const struct GNUNET_PeerIdentity *get_path,
- unsigned int get_path_length,
- const struct GNUNET_PeerIdentity *put_path,
- unsigned int put_path_length,
- enum GNUNET_BLOCK_Type type,
- size_t size, const void *data)
-{
- const struct RegexBlock *block = data;
- struct RegexSearchContext *ctx = cls;
- struct REGEX_ITERNAL_Search *info = ctx->info;
- void *copy;
- size_t len;
- char *datastore;
-
-#if DEBUG_DHT
- if (NULL != put_path && 0 != put_path_length)
- {
- datastore = GNUNET_strdup (GNUNET_i2s (&put_path[put_path_length - 1]));
- }
- else
- {
- GNUNET_asprintf (&datastore, "?? %u/%u", put_path_length, get_path_length);
- }
-#else
- datastore = GNUNET_strdup ("N/A");
-#endif
-
- LOG (GNUNET_ERROR_TYPE_INFO, " DHT GET result for %s (%s) at %s\n",
- GNUNET_h2s (key), ctx->info->description, datastore);
- GNUNET_free (datastore);
-
- copy = GNUNET_malloc (size);
- memcpy (copy, data, size);
- GNUNET_break (
- GNUNET_OK ==
- GNUNET_CONTAINER_multihashmap_put (info->dht_get_results,
- &((struct RegexBlock *)copy)->key, copy,
-
GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE)
- );
- len = ntohl (block->n_proof);
- {
- char proof[len + 1];
-
- memcpy (proof, &block[1], len);
- proof[len] = '\0';
- if (GNUNET_OK != REGEX_ITERNAL_check_proof (proof, key))
- {
- GNUNET_break_op (0);
- return;
- }
- }
- len = strlen (info->description);
- if (len == ctx->position) // String processed
- {
- if (GNUNET_YES == ntohl (block->accepting))
- {
- regex_find_path (key, ctx);
- }
- else
- {
- LOG (GNUNET_ERROR_TYPE_INFO, " block not accepting!\n");
- // FIXME REGEX this block not successful, wait for more? start timeout?
- }
- return;
- }
-
- regex_next_edge (block, size, ctx);
-
- return;
-}
-
-
-/**
- * Iterator over found existing mesh regex blocks that match an ongoing search.
- *
- * @param cls Closure (current context)-
- * @param key Current key code (key for cached block).
- * @param value Value in the hash map (cached RegexBlock).
- * @return GNUNET_YES: we should always continue to iterate.
- */
-static int
-regex_result_iterator (void *cls,
- const struct GNUNET_HashCode * key,
- void *value)
-{
- struct RegexBlock *block = value;
- struct RegexSearchContext *ctx = cls;
-
- if (GNUNET_YES == ntohl(block->accepting) &&
- ctx->position == strlen (ctx->info->description))
- {
- LOG (GNUNET_ERROR_TYPE_INFO, " * Found accepting known block\n");
- regex_find_path (key, ctx);
- return GNUNET_YES; // We found an accept state!
- }
- LOG (GNUNET_ERROR_TYPE_DEBUG, "* %u, %u, [%u]\n",
- ctx->position, strlen(ctx->info->description),
- ntohl(block->accepting));
-
- regex_next_edge (block, SIZE_MAX, ctx);
-
- GNUNET_STATISTICS_update (ctx->info->stats, "# regex mesh blocks iterated",
- 1, GNUNET_NO);
-
- return GNUNET_YES;
-}
-
-
-/**
- * Iterator over edges in a regex block retrieved from the DHT.
- *
- * @param cls Closure (context of the search).
- * @param token Token that follows to next state.
- * @param len Lenght of token.
- * @param key Hash of next state.
- *
- * @return GNUNET_YES if should keep iterating, GNUNET_NO otherwise.
- */
-static int
-regex_edge_iterator (void *cls,
- const char *token,
- size_t len,
- const struct GNUNET_HashCode *key)
-{
- struct RegexSearchContext *ctx = cls;
- struct REGEX_ITERNAL_Search *info = ctx->info;
- const char *current;
- size_t current_len;
-
- GNUNET_STATISTICS_update (info->stats, "# regex edges iterated",
- 1, GNUNET_NO);
-
- LOG (GNUNET_ERROR_TYPE_DEBUG, "* Start of regex edge iterator\n");
- LOG (GNUNET_ERROR_TYPE_DEBUG, "* descr : %s\n", info->description);
- LOG (GNUNET_ERROR_TYPE_DEBUG, "* posit : %u\n", ctx->position);
- current = &info->description[ctx->position];
- LOG (GNUNET_ERROR_TYPE_DEBUG, "* currt : %s\n", current);
- current_len = strlen (info->description) - ctx->position;
- LOG (GNUNET_ERROR_TYPE_DEBUG, "* ctlen : %u\n", current_len);
- LOG (GNUNET_ERROR_TYPE_DEBUG, "* tklen : %u\n", len);
- LOG (GNUNET_ERROR_TYPE_DEBUG, "* token : %.*s\n", len, token);
- LOG (GNUNET_ERROR_TYPE_DEBUG, "* nextk : %s\n", GNUNET_h2s(key));
- if (len > current_len)
- {
- LOG (GNUNET_ERROR_TYPE_DEBUG, "* Token too long, END\n");
- return GNUNET_YES; // Token too long, wont match
- }
- if (0 != strncmp (current, token, len))
- {
- LOG (GNUNET_ERROR_TYPE_DEBUG, "* Token doesn't match, END\n");
- return GNUNET_YES; // Token doesn't match
- }
-
- if (len > ctx->longest_match)
- {
- LOG (GNUNET_ERROR_TYPE_DEBUG, "* Token is longer, KEEP\n");
- ctx->longest_match = len;
- ctx->hash = *key;
- }
- else
- {
- LOG (GNUNET_ERROR_TYPE_DEBUG, "* Token is not longer, IGNORE\n");
- }
-
- LOG (GNUNET_ERROR_TYPE_DEBUG, "* End of regex edge iterator\n");
- return GNUNET_YES;
-}
-
-
-/**
- * Jump to the next edge, with the longest matching token.
- *
- * @param block Block found in the DHT.
- * @param size Size of the block.
- * @param ctx Context of the search.
- *
- * @return GNUNET_YES if should keep iterating, GNUNET_NO otherwise.
- */
-static void
-regex_next_edge (const struct RegexBlock *block,
- size_t size,
- struct RegexSearchContext *ctx)
-{
- struct RegexSearchContext *new_ctx;
- struct REGEX_ITERNAL_Search *info = ctx->info;
- struct GNUNET_DHT_GetHandle *get_h;
- struct GNUNET_HashCode *hash;
- const char *rest;
- int result;
-
- /* Find the longest match for the current string position,
- * among tokens in the given block */
- ctx->longest_match = 0;
- result = REGEX_ITERNAL_block_iterate (block, size,
- ®ex_edge_iterator, ctx);
- GNUNET_break (GNUNET_OK == result);
-
- /* Did anything match? */
- if (0 == ctx->longest_match)
- {
- LOG (GNUNET_ERROR_TYPE_DEBUG, " no match in block\n");
- return;
- }
-
- hash = &ctx->hash;
- new_ctx = GNUNET_malloc (sizeof (struct RegexSearchContext));
- new_ctx->info = info;
- new_ctx->position = ctx->position + ctx->longest_match;
- GNUNET_array_append (info->contexts, info->n_contexts, new_ctx);
-
- /* Check whether we already have a DHT GET running for it */
- if (GNUNET_YES ==
- GNUNET_CONTAINER_multihashmap_contains (info->dht_get_handles, hash))
- {
- LOG (GNUNET_ERROR_TYPE_DEBUG, "* GET for %s running, END\n",
- GNUNET_h2s (hash));
- GNUNET_CONTAINER_multihashmap_get_multiple (info->dht_get_results,
- hash,
- ®ex_result_iterator,
- new_ctx);
- return; /* We are already looking for it */
- }
-
- GNUNET_STATISTICS_update (info->stats, "# regex nodes traversed",
- 1, GNUNET_NO);
-
- /* Start search in DHT */
- LOG (GNUNET_ERROR_TYPE_INFO, " looking for %s\n", GNUNET_h2s (hash));
- rest = &new_ctx->info->description[new_ctx->position];
- get_h =
- GNUNET_DHT_get_start (info->dht, /* handle */
- GNUNET_BLOCK_TYPE_REGEX, /* type */
- hash, /* key to search */
- DHT_REPLICATION, /* replication level */
- DHT_OPT,
- rest, /* xquery */
- // FIXME add BLOOMFILTER to exclude filtered peers
- strlen(rest) + 1, /* xquery bits */
- // FIXME add BLOOMFILTER SIZE
- &dht_get_string_handler, new_ctx);
- if (GNUNET_OK !=
- GNUNET_CONTAINER_multihashmap_put(info->dht_get_handles,
- hash,
- get_h,
-
GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
- {
- GNUNET_break (0);
- return;
- }
-}
-
-
-struct REGEX_ITERNAL_Search *
-REGEX_ITERNAL_search (struct GNUNET_DHT_Handle *dht,
- const char *string,
- REGEX_ITERNAL_Found callback,
- void *callback_cls,
- struct GNUNET_STATISTICS_Handle *stats)
-{
- struct REGEX_ITERNAL_Search *h;
- struct GNUNET_DHT_GetHandle *get_h;
- struct RegexSearchContext *ctx;
- struct GNUNET_HashCode key;
- size_t size;
- size_t len;
-
- /* Initialize handle */
- LOG (GNUNET_ERROR_TYPE_INFO, "REGEX_ITERNAL_search: %s\n", string);
- GNUNET_assert (NULL != dht);
- GNUNET_assert (NULL != callback);
- h = GNUNET_malloc (sizeof (struct REGEX_ITERNAL_Search));
- h->dht = dht;
- h->description = GNUNET_strdup (string);
- h->callback = callback;
- h->callback_cls = callback_cls;
- h->stats = stats;
- h->dht_get_handles = GNUNET_CONTAINER_multihashmap_create (32, GNUNET_NO);
- h->dht_get_results = GNUNET_CONTAINER_multihashmap_create (32, GNUNET_YES);
-
- /* Initialize context */
- len = strlen (string);
- size = REGEX_ITERNAL_get_first_key (string, len, &key);
- ctx = GNUNET_malloc (sizeof (struct RegexSearchContext));
- ctx->position = size;
- ctx->info = h;
- GNUNET_array_append (h->contexts, h->n_contexts, ctx);
- LOG (GNUNET_ERROR_TYPE_DEBUG, " consumed %u bits out of %u\n", size, len);
- LOG (GNUNET_ERROR_TYPE_INFO, " looking for %s\n", GNUNET_h2s (&key));
-
- /* Start search in DHT */
- get_h = GNUNET_DHT_get_start (h->dht, /* handle */
- GNUNET_BLOCK_TYPE_REGEX, /* type */
- &key, /* key to search */
- DHT_REPLICATION, /* replication level */
- DHT_OPT,
- &h->description[size], /* xquery */
- // FIXME add BLOOMFILTER to exclude filtered
peers
- len + 1 - size, /* xquery bits
*/
- // FIXME add BLOOMFILTER SIZE
- &dht_get_string_handler, ctx);
- GNUNET_break (
- GNUNET_OK ==
- GNUNET_CONTAINER_multihashmap_put (h->dht_get_handles,
- &key,
- get_h,
-
GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST)
- );
-
- return h;
-}
-
-
-/**
- * Iterator over hash map entries to cancel DHT GET requests after a
- * successful connect_by_string.
- *
- * @param cls Closure (unused).
- * @param key Current key code (unused).
- * @param value Value in the hash map (get handle).
- * @return GNUNET_YES if we should continue to iterate,
- * GNUNET_NO if not.
- */
-static int
-regex_cancel_dht_get (void *cls,
- const struct GNUNET_HashCode * key,
- void *value)
-{
- struct GNUNET_DHT_GetHandle *h = value;
-
- GNUNET_DHT_get_stop (h);
- return GNUNET_YES;
-}
-
-
-/**
- * Iterator over hash map entries to free MeshRegexBlocks stored during the
- * search for connect_by_string.
- *
- * @param cls Closure (unused).
- * @param key Current key code (unused).
- * @param value MeshRegexBlock in the hash map.
- * @return GNUNET_YES if we should continue to iterate,
- * GNUNET_NO if not.
- */
-static int
-regex_free_result (void *cls,
- const struct GNUNET_HashCode * key,
- void *value)
-{
-
- GNUNET_free (value);
- return GNUNET_YES;
-}
-
-
-/**
- * Cancel an ongoing regex search in the DHT and free all resources.
- *
- * @param ctx The search context.
- */
-static void
-regex_cancel_search (struct REGEX_ITERNAL_Search *ctx)
-{
- GNUNET_free (ctx->description);
- GNUNET_CONTAINER_multihashmap_iterate (ctx->dht_get_handles,
- ®ex_cancel_dht_get, NULL);
- GNUNET_CONTAINER_multihashmap_iterate (ctx->dht_get_results,
- ®ex_free_result, NULL);
- GNUNET_CONTAINER_multihashmap_destroy (ctx->dht_get_results);
- GNUNET_CONTAINER_multihashmap_destroy (ctx->dht_get_handles);
- if (0 < ctx->n_contexts)
- {
- int i;
-
- for (i = 0; i < ctx->n_contexts; i++)
- {
- GNUNET_free (ctx->contexts[i]);
- }
- GNUNET_free (ctx->contexts);
- }
-}
-
-void
-REGEX_ITERNAL_search_cancel (struct REGEX_ITERNAL_Search *h)
-{
- regex_cancel_search (h);
- GNUNET_free (h);
-}
-
-
-
-/* end of regex_dht.c */
Deleted: gnunet/src/regex/regex_graph.c
===================================================================
--- gnunet/src/regex/regex_graph.c 2013-06-20 08:32:50 UTC (rev 27498)
+++ gnunet/src/regex/regex_graph.c 2013-06-20 08:55:56 UTC (rev 27499)
@@ -1,317 +0,0 @@
-/*
- This file is part of GNUnet
- (C) 2012 Christian Grothoff (and other contributing authors)
-
- GNUnet is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published
- by the Free Software Foundation; either version 3, or (at your
- option) any later version.
-
- GNUnet is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with GNUnet; see the file COPYING. If not, write to the
- Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA.
-*/
-/**
- * @file src/regex/regex_graph.c
- * @brief functions for creating .dot graphs from regexes
- * @author Maximilian Szengel
- */
-#include "platform.h"
-#include "regex_internal_lib.h"
-#include "regex_internal.h"
-
-/**
- * Context for graph creation. Passed as the cls to
- * REGEX_ITERNAL_automaton_save_graph_step.
- */
-struct REGEX_ITERNAL_Graph_Context
-{
- /**
- * File pointer to the dot file used for output.
- */
- FILE *filep;
-
- /**
- * Verbose flag, if it's set to GNUNET_YES additional info will be printed in
- * the graph.
- */
- int verbose;
-
- /**
- * Coloring flag, if set to GNUNET_YES SCCs will be colored.
- */
- int coloring;
-};
-
-
-/**
- * Recursive function doing DFS with 'v' as a start, detecting all SCCs inside
- * the subgraph reachable from 'v'. Used with scc_tarjan function to detect all
- * SCCs inside an automaton.
- *
- * @param scc_counter counter for numbering the sccs
- * @param v start vertex
- * @param index current index
- * @param stack stack for saving all SCCs
- * @param stack_size current size of the stack
- */
-static void
-scc_tarjan_strongconnect (unsigned int *scc_counter,
- struct REGEX_ITERNAL_State *v, unsigned int *index,
- struct REGEX_ITERNAL_State **stack,
- unsigned int *stack_size)
-{
- struct REGEX_ITERNAL_State *w;
- struct REGEX_ITERNAL_Transition *t;
-
- v->index = *index;
- v->lowlink = *index;
- (*index)++;
- stack[(*stack_size)++] = v;
- v->contained = 1;
-
- for (t = v->transitions_head; NULL != t; t = t->next)
- {
- w = t->to_state;
-
- if (NULL == w)
- continue;
-
- if (w->index < 0)
- {
- scc_tarjan_strongconnect (scc_counter, w, index, stack, stack_size);
- v->lowlink = (v->lowlink > w->lowlink) ? w->lowlink : v->lowlink;
- }
- else if (1 == w->contained)
- v->lowlink = (v->lowlink > w->index) ? w->index : v->lowlink;
- }
-
- if (v->lowlink == v->index)
- {
- (*scc_counter)++;
- do
- {
- w = stack[--(*stack_size)];
- w->contained = 0;
- w->scc_id = *scc_counter;
- }
- while (w != v);
- }
-}
-
-
-/**
- * Detect all SCCs (Strongly Connected Components) inside the given automaton.
- * SCCs will be marked using the scc_id on each state.
- *
- * @param a the automaton for which SCCs should be computed and assigned.
- */
-static void
-scc_tarjan (struct REGEX_ITERNAL_Automaton *a)
-{
- unsigned int index;
- unsigned int scc_counter;
- struct REGEX_ITERNAL_State *v;
- struct REGEX_ITERNAL_State *stack[a->state_count];
- unsigned int stack_size;
-
- for (v = a->states_head; NULL != v; v = v->next)
- {
- v->contained = 0;
- v->index = -1;
- v->lowlink = -1;
- }
-
- stack_size = 0;
- index = 0;
- scc_counter = 0;
-
- for (v = a->states_head; NULL != v; v = v->next)
- {
- if (v->index < 0)
- scc_tarjan_strongconnect (&scc_counter, v, &index, stack, &stack_size);
- }
-}
-
-
-/**
- * Save a state to an open file pointer. cls is expected to be a file pointer
to
- * an open file. Used only in conjunction with
- * REGEX_ITERNAL_automaton_save_graph.
- *
- * @param cls file pointer.
- * @param count current count of the state, not used.
- * @param s state.
- */
-void
-REGEX_ITERNAL_automaton_save_graph_step (void *cls, unsigned int count,
- struct REGEX_ITERNAL_State *s)
-{
- struct REGEX_ITERNAL_Graph_Context *ctx = cls;
- struct REGEX_ITERNAL_Transition *ctran;
- char *s_acc = NULL;
- char *s_tran = NULL;
- char *name;
- char *to_name;
-
- if (GNUNET_YES == ctx->verbose)
- GNUNET_asprintf (&name, "%i (%s) (%s) (%s)", s->dfs_id, s->name, s->proof,
- GNUNET_h2s (&s->hash));
- else
- GNUNET_asprintf (&name, "%i", s->dfs_id);
-
- if (s->accepting)
- {
- if (GNUNET_YES == ctx->coloring)
- {
- GNUNET_asprintf (&s_acc,
- "\"%s\" [shape=doublecircle, color=\"0.%i 0.8
0.95\"];\n",
- name, s->scc_id * s->scc_id);
- }
- else
- {
- GNUNET_asprintf (&s_acc, "\"%s\" [shape=doublecircle];\n", name,
- s->scc_id);
- }
- }
- else if (GNUNET_YES == ctx->coloring)
- {
- GNUNET_asprintf (&s_acc,
- "\"%s\" [shape=circle, color=\"0.%i 0.8 0.95\"];\n", name,
- s->scc_id * s->scc_id);
- }
- else
- {
- GNUNET_asprintf (&s_acc, "\"%s\" [shape=circle];\n", name, s->scc_id);
- }
-
- GNUNET_assert (NULL != s_acc);
-
- fwrite (s_acc, strlen (s_acc), 1, ctx->filep);
- GNUNET_free (s_acc);
- s_acc = NULL;
-
- for (ctran = s->transitions_head; NULL != ctran; ctran = ctran->next)
- {
- if (NULL == ctran->to_state)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "Transition from State %i has no state for transitioning\n",
- s->id);
- continue;
- }
-
- if (GNUNET_YES == ctx->verbose)
- {
- GNUNET_asprintf (&to_name, "%i (%s) (%s) (%s)", ctran->to_state->dfs_id,
- ctran->to_state->name, ctran->to_state->proof,
- GNUNET_h2s (&ctran->to_state->hash));
- }
- else
- GNUNET_asprintf (&to_name, "%i", ctran->to_state->dfs_id);
-
- if (NULL == ctran->label)
- {
- if (GNUNET_YES == ctx->coloring)
- {
- GNUNET_asprintf (&s_tran,
- "\"%s\" -> \"%s\" [label = \"ε\", color=\"0.%i 0.8
0.95\"];\n",
- name, to_name, s->scc_id * s->scc_id);
- }
- else
- {
- GNUNET_asprintf (&s_tran, "\"%s\" -> \"%s\" [label = \"ε\"];\n", name,
- to_name, s->scc_id);
- }
- }
- else
- {
- if (GNUNET_YES == ctx->coloring)
- {
- GNUNET_asprintf (&s_tran,
- "\"%s\" -> \"%s\" [label = \"%s\", color=\"0.%i 0.8
0.95\"];\n",
- name, to_name, ctran->label, s->scc_id * s->scc_id);
- }
- else
- {
- GNUNET_asprintf (&s_tran, "\"%s\" -> \"%s\" [label = \"%s\"];\n", name,
- to_name, ctran->label, s->scc_id);
- }
- }
-
- GNUNET_free (to_name);
-
- GNUNET_assert (NULL != s_tran);
-
- fwrite (s_tran, strlen (s_tran), 1, ctx->filep);
- GNUNET_free (s_tran);
- s_tran = NULL;
- }
-
- GNUNET_free (name);
-}
-
-
-/**
- * Save the given automaton as a GraphViz dot file.
- *
- * @param a the automaton to be saved.
- * @param filename where to save the file.
- * @param options options for graph generation that include coloring or verbose
- * mode
- */
-void
-REGEX_ITERNAL_automaton_save_graph (struct REGEX_ITERNAL_Automaton *a,
- const char *filename,
- enum REGEX_ITERNAL_GraphSavingOptions
options)
-{
- char *start;
- char *end;
- struct REGEX_ITERNAL_Graph_Context ctx;
-
- if (NULL == a)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Could not print NFA, was NULL!");
- return;
- }
-
- if (NULL == filename || strlen (filename) < 1)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No Filename given!");
- return;
- }
-
- ctx.filep = fopen (filename, "w");
- ctx.verbose =
- (0 == (options & REGEX_ITERNAL_GRAPH_VERBOSE)) ? GNUNET_NO : GNUNET_YES;
- ctx.coloring =
- (0 == (options & REGEX_ITERNAL_GRAPH_COLORING)) ? GNUNET_NO : GNUNET_YES;
-
- if (NULL == ctx.filep)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Could not open file for writing: %s",
- filename);
- return;
- }
-
- /* First add the SCCs to the automaton, so we can color them nicely */
- if (GNUNET_YES == ctx.coloring)
- scc_tarjan (a);
-
- start = "digraph G {\nrankdir=LR\n";
- fwrite (start, strlen (start), 1, ctx.filep);
-
- REGEX_ITERNAL_automaton_traverse (a, a->start, NULL, NULL,
- ®EX_ITERNAL_automaton_save_graph_step,
- &ctx);
-
- end = "\n}\n";
- fwrite (end, strlen (end), 1, ctx.filep);
- fclose (ctx.filep);
-}
Copied: gnunet/src/regex/regex_internal.c (from rev 27498,
gnunet/src/regex/regex.c)
===================================================================
--- gnunet/src/regex/regex_internal.c (rev 0)
+++ gnunet/src/regex/regex_internal.c 2013-06-20 08:55:56 UTC (rev 27499)
@@ -0,0 +1,3485 @@
+/*
+ This file is part of GNUnet
+ (C) 2012 Christian Grothoff (and other contributing authors)
+
+ GNUnet is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published
+ by the Free Software Foundation; either version 3, or (at your
+ option) any later version.
+
+ GNUnet is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GNUnet; see the file COPYING. If not, write to the
+ Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA.
+*/
+/**
+ * @file src/regex/regex_internal.c
+ * @brief library to create Deterministic Finite Automatons (DFAs) from regular
+ * expressions (regexes).
+ * @author Maximilian Szengel
+ */
+#include "platform.h"
+#include "gnunet_util_lib.h"
+#include "gnunet_regex_service.h"
+#include "regex_internal_lib.h"
+#include "regex_internal.h"
+
+
+/**
+ * Set this to GNUNET_YES to enable state naming. Used to debug NFA->DFA
+ * creation. Disabled by default for better performance.
+ */
+#define REGEX_DEBUG_DFA GNUNET_NO
+
+/**
+ * Set of states using MDLL API.
+ */
+struct REGEX_ITERNAL_StateSet_MDLL
+{
+ /**
+ * MDLL of states.
+ */
+ struct REGEX_ITERNAL_State *head;
+
+ /**
+ * MDLL of states.
+ */
+ struct REGEX_ITERNAL_State *tail;
+
+ /**
+ * Length of the MDLL.
+ */
+ unsigned int len;
+};
+
+
+/**
+ * Append state to the given StateSet '
+ *
+ * @param set set to be modified
+ * @param state state to be appended
+ */
+static void
+state_set_append (struct REGEX_ITERNAL_StateSet *set,
+ struct REGEX_ITERNAL_State *state)
+{
+ if (set->off == set->size)
+ GNUNET_array_grow (set->states, set->size, set->size * 2 + 4);
+ set->states[set->off++] = state;
+}
+
+
+/**
+ * Compare two strings for equality. If either is NULL they are not equal.
+ *
+ * @param str1 first string for comparison.
+ * @param str2 second string for comparison.
+ *
+ * @return 0 if the strings are the same or both NULL, 1 or -1 if not.
+ */
+static int
+nullstrcmp (const char *str1, const char *str2)
+{
+ if ((NULL == str1) != (NULL == str2))
+ return -1;
+ if ((NULL == str1) && (NULL == str2))
+ return 0;
+
+ return strcmp (str1, str2);
+}
+
+
+/**
+ * Adds a transition from one state to another on 'label'. Does not add
+ * duplicate states.
+ *
+ * @param ctx context
+ * @param from_state starting state for the transition
+ * @param label transition label
+ * @param to_state state to where the transition should point to
+ */
+static void
+state_add_transition (struct REGEX_ITERNAL_Context *ctx,
+ struct REGEX_ITERNAL_State *from_state, const char
*label,
+ struct REGEX_ITERNAL_State *to_state)
+{
+ struct REGEX_ITERNAL_Transition *t;
+ struct REGEX_ITERNAL_Transition *oth;
+
+ if (NULL == from_state)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Could not create Transition.\n");
+ return;
+ }
+
+ /* Do not add duplicate state transitions */
+ for (t = from_state->transitions_head; NULL != t; t = t->next)
+ {
+ if (t->to_state == to_state && 0 == nullstrcmp (t->label, label) &&
+ t->from_state == from_state)
+ return;
+ }
+
+ /* sort transitions by label */
+ for (oth = from_state->transitions_head; NULL != oth; oth = oth->next)
+ {
+ if (0 < nullstrcmp (oth->label, label))
+ break;
+ }
+
+ t = GNUNET_malloc (sizeof (struct REGEX_ITERNAL_Transition));
+ if (NULL != ctx)
+ t->id = ctx->transition_id++;
+ if (NULL != label)
+ t->label = GNUNET_strdup (label);
+ else
+ t->label = NULL;
+ t->to_state = to_state;
+ t->from_state = from_state;
+
+ /* Add outgoing transition to 'from_state' */
+ from_state->transition_count++;
+ GNUNET_CONTAINER_DLL_insert_before (from_state->transitions_head,
+ from_state->transitions_tail, oth, t);
+}
+
+
+/**
+ * Remove a 'transition' from 'state'.
+ *
+ * @param state state from which the to-be-removed transition originates.
+ * @param transition transition that should be removed from state 'state'.
+ */
+static void
+state_remove_transition (struct REGEX_ITERNAL_State *state,
+ struct REGEX_ITERNAL_Transition *transition)
+{
+ if (NULL == state || NULL == transition)
+ return;
+
+ if (transition->from_state != state)
+ return;
+
+ GNUNET_free_non_null (transition->label);
+
+ state->transition_count--;
+ GNUNET_CONTAINER_DLL_remove (state->transitions_head,
state->transitions_tail,
+ transition);
+
+ GNUNET_free (transition);
+}
+
+
+/**
+ * Compare two states. Used for sorting.
+ *
+ * @param a first state
+ * @param b second state
+ *
+ * @return an integer less than, equal to, or greater than zero
+ * if the first argument is considered to be respectively
+ * less than, equal to, or greater than the second.
+ */
+static int
+state_compare (const void *a, const void *b)
+{
+ struct REGEX_ITERNAL_State **s1 = (struct REGEX_ITERNAL_State **) a;
+ struct REGEX_ITERNAL_State **s2 = (struct REGEX_ITERNAL_State **) b;
+
+ return (*s1)->id - (*s2)->id;
+}
+
+
+/**
+ * Get all edges leaving state 's'.
+ *
+ * @param s state.
+ * @param edges all edges leaving 's', expected to be allocated and have enough
+ * space for s->transitions_count elements.
+ *
+ * @return number of edges.
+ */
+static unsigned int
+state_get_edges (struct REGEX_ITERNAL_State *s, struct REGEX_ITERNAL_Edge
*edges)
+{
+ struct REGEX_ITERNAL_Transition *t;
+ unsigned int count;
+
+ if (NULL == s)
+ return 0;
+
+ count = 0;
+
+ for (t = s->transitions_head; NULL != t; t = t->next)
+ {
+ if (NULL != t->to_state)
+ {
+ edges[count].label = t->label;
+ edges[count].destination = t->to_state->hash;
+ count++;
+ }
+ }
+ return count;
+}
+
+
+/**
+ * Compare to state sets by comparing the id's of the states that are contained
+ * in each set. Both sets are expected to be sorted by id!
+ *
+ * @param sset1 first state set
+ * @param sset2 second state set
+ * @return 0 if the sets are equal, otherwise non-zero
+ */
+static int
+state_set_compare (struct REGEX_ITERNAL_StateSet *sset1,
+ struct REGEX_ITERNAL_StateSet *sset2)
+{
+ int result;
+ unsigned int i;
+
+ if (NULL == sset1 || NULL == sset2)
+ return 1;
+
+ result = sset1->off - sset2->off;
+ if (result < 0)
+ return -1;
+ if (result > 0)
+ return 1;
+ for (i = 0; i < sset1->off; i++)
+ if (0 != (result = state_compare (&sset1->states[i], &sset2->states[i])))
+ break;
+ return result;
+}
+
+
+/**
+ * Clears the given StateSet 'set'
+ *
+ * @param set set to be cleared
+ */
+static void
+state_set_clear (struct REGEX_ITERNAL_StateSet *set)
+{
+ GNUNET_array_grow (set->states, set->size, 0);
+ set->off = 0;
+}
+
+
+/**
+ * Clears an automaton fragment. Does not destroy the states inside the
+ * automaton.
+ *
+ * @param a automaton to be cleared
+ */
+static void
+automaton_fragment_clear (struct REGEX_ITERNAL_Automaton *a)
+{
+ if (NULL == a)
+ return;
+
+ a->start = NULL;
+ a->end = NULL;
+ a->states_head = NULL;
+ a->states_tail = NULL;
+ a->state_count = 0;
+ GNUNET_free (a);
+}
+
+
+/**
+ * Frees the memory used by State 's'
+ *
+ * @param s state that should be destroyed
+ */
+static void
+automaton_destroy_state (struct REGEX_ITERNAL_State *s)
+{
+ struct REGEX_ITERNAL_Transition *t;
+ struct REGEX_ITERNAL_Transition *next_t;
+
+ if (NULL == s)
+ return;
+
+ GNUNET_free_non_null (s->name);
+ GNUNET_free_non_null (s->proof);
+ state_set_clear (&s->nfa_set);
+ for (t = s->transitions_head; NULL != t; t = next_t)
+ {
+ next_t = t->next;
+ state_remove_transition (s, t);
+ }
+
+ GNUNET_free (s);
+}
+
+
+/**
+ * Remove a state from the given automaton 'a'. Always use this function when
+ * altering the states of an automaton. Will also remove all transitions
leading
+ * to this state, before destroying it.
+ *
+ * @param a automaton
+ * @param s state to remove
+ */
+static void
+automaton_remove_state (struct REGEX_ITERNAL_Automaton *a,
+ struct REGEX_ITERNAL_State *s)
+{
+ struct REGEX_ITERNAL_State *s_check;
+ struct REGEX_ITERNAL_Transition *t_check;
+ struct REGEX_ITERNAL_Transition *t_check_next;
+
+ if (NULL == a || NULL == s)
+ return;
+
+ /* remove all transitions leading to this state */
+ for (s_check = a->states_head; NULL != s_check; s_check = s_check->next)
+ {
+ for (t_check = s_check->transitions_head; NULL != t_check;
+ t_check = t_check_next)
+ {
+ t_check_next = t_check->next;
+ if (t_check->to_state == s)
+ state_remove_transition (s_check, t_check);
+ }
+ }
+
+ /* remove state */
+ GNUNET_CONTAINER_DLL_remove (a->states_head, a->states_tail, s);
+ a->state_count--;
+
+ automaton_destroy_state (s);
+}
+
+
+/**
+ * Merge two states into one. Will merge 's1' and 's2' into 's1' and destroy
+ * 's2'. 's1' will contain all (non-duplicate) outgoing transitions of 's2'.
+ *
+ * @param ctx context
+ * @param a automaton
+ * @param s1 first state
+ * @param s2 second state, will be destroyed
+ */
+static void
+automaton_merge_states (struct REGEX_ITERNAL_Context *ctx,
+ struct REGEX_ITERNAL_Automaton *a,
+ struct REGEX_ITERNAL_State *s1,
+ struct REGEX_ITERNAL_State *s2)
+{
+ struct REGEX_ITERNAL_State *s_check;
+ struct REGEX_ITERNAL_Transition *t_check;
+ struct REGEX_ITERNAL_Transition *t;
+ struct REGEX_ITERNAL_Transition *t_next;
+ int is_dup;
+
+ if (s1 == s2)
+ return;
+
+ /* 1. Make all transitions pointing to s2 point to s1, unless this transition
+ * does not already exists, if it already exists remove transition. */
+ for (s_check = a->states_head; NULL != s_check; s_check = s_check->next)
+ {
+ for (t_check = s_check->transitions_head; NULL != t_check; t_check =
t_next)
+ {
+ t_next = t_check->next;
+
+ if (s2 == t_check->to_state)
+ {
+ is_dup = GNUNET_NO;
+ for (t = t_check->from_state->transitions_head; NULL != t; t = t->next)
+ {
+ if (t->to_state == s1 && 0 == strcmp (t_check->label, t->label))
+ is_dup = GNUNET_YES;
+ }
+ if (GNUNET_NO == is_dup)
+ t_check->to_state = s1;
+ else
+ state_remove_transition (t_check->from_state, t_check);
+ }
+ }
+ }
+
+ /* 2. Add all transitions from s2 to sX to s1 */
+ for (t_check = s2->transitions_head; NULL != t_check; t_check =
t_check->next)
+ {
+ if (t_check->to_state != s1)
+ state_add_transition (ctx, s1, t_check->label, t_check->to_state);
+ }
+
+ /* 3. Rename s1 to {s1,s2} */
+#if REGEX_DEBUG_DFA
+ char *new_name;
+
+ new_name = s1->name;
+ GNUNET_asprintf (&s1->name, "{%s,%s}", new_name, s2->name);
+ GNUNET_free (new_name);
+#endif
+
+ /* remove state */
+ GNUNET_CONTAINER_DLL_remove (a->states_head, a->states_tail, s2);
+ a->state_count--;
+ automaton_destroy_state (s2);
+}
+
+
+/**
+ * Add a state to the automaton 'a', always use this function to alter the
+ * states DLL of the automaton.
+ *
+ * @param a automaton to add the state to
+ * @param s state that should be added
+ */
+static void
+automaton_add_state (struct REGEX_ITERNAL_Automaton *a,
+ struct REGEX_ITERNAL_State *s)
+{
+ GNUNET_CONTAINER_DLL_insert (a->states_head, a->states_tail, s);
+ a->state_count++;
+}
+
+
+/**
+ * Depth-first traversal (DFS) of all states that are reachable from state
+ * 's'. Performs 'action' on each visited state.
+ *
+ * @param s start state.
+ * @param marks an array of size a->state_count to remember which state was
+ * already visited.
+ * @param count current count of the state.
+ * @param check function that is checked before advancing on each transition
+ * in the DFS.
+ * @param check_cls closure for check.
+ * @param action action to be performed on each state.
+ * @param action_cls closure for action.
+ */
+static void
+automaton_state_traverse (struct REGEX_ITERNAL_State *s, int *marks,
+ unsigned int *count,
+ REGEX_ITERNAL_traverse_check check, void *check_cls,
+ REGEX_ITERNAL_traverse_action action, void
*action_cls)
+{
+ struct REGEX_ITERNAL_Transition *t;
+
+ if (GNUNET_YES == marks[s->traversal_id])
+ return;
+
+ marks[s->traversal_id] = GNUNET_YES;
+
+ if (NULL != action)
+ action (action_cls, *count, s);
+
+ (*count)++;
+
+ for (t = s->transitions_head; NULL != t; t = t->next)
+ {
+ if (NULL == check ||
+ (NULL != check && GNUNET_YES == check (check_cls, s, t)))
+ {
+ automaton_state_traverse (t->to_state, marks, count, check, check_cls,
+ action, action_cls);
+ }
+ }
+}
+
+
+/**
+ * Traverses the given automaton using depth-first-search (DFS) from it's start
+ * state, visiting all reachable states and calling 'action' on each one of
+ * them.
+ *
+ * @param a automaton to be traversed.
+ * @param start start state, pass a->start or NULL to traverse the whole
automaton.
+ * @param check function that is checked before advancing on each transition
+ * in the DFS.
+ * @param check_cls closure for check.
+ * @param action action to be performed on each state.
+ * @param action_cls closure for action
+ */
+void
+REGEX_ITERNAL_automaton_traverse (const struct REGEX_ITERNAL_Automaton *a,
+ struct REGEX_ITERNAL_State *start,
+ REGEX_ITERNAL_traverse_check check,
+ void *check_cls,
+ REGEX_ITERNAL_traverse_action action,
+ void *action_cls)
+{
+ unsigned int count;
+ struct REGEX_ITERNAL_State *s;
+
+ if (NULL == a || 0 == a->state_count)
+ return;
+
+ int marks[a->state_count];
+
+ for (count = 0, s = a->states_head; NULL != s && count < a->state_count;
+ s = s->next, count++)
+ {
+ s->traversal_id = count;
+ marks[s->traversal_id] = GNUNET_NO;
+ }
+
+ count = 0;
+
+ if (NULL == start)
+ s = a->start;
+ else
+ s = start;
+
+ automaton_state_traverse (s, marks, &count, check, check_cls, action,
+ action_cls);
+}
+
+
+/**
+ * String container for faster string operations.
+ */
+struct StringBuffer
+{
+ /**
+ * Buffer holding the string (may start in the middle!);
+ * NOT 0-terminated!
+ */
+ char *sbuf;
+
+ /**
+ * Allocated buffer.
+ */
+ char *abuf;
+
+ /**
+ * Length of the string in the buffer.
+ */
+ size_t slen;
+
+ /**
+ * Number of bytes allocated for 'sbuf'
+ */
+ unsigned int blen;
+
+ /**
+ * Buffer currently represents "NULL" (not the empty string!)
+ */
+ int16_t null_flag;
+
+ /**
+ * If this entry is part of the last/current generation array,
+ * this flag is GNUNET_YES if the last and current generation are
+ * identical (and thus copying is unnecessary if the value didn't
+ * change). This is used in an optimization that improves
+ * performance by about 1% --- if we use int16_t here. With just
+ * "int" for both flags, performance drops (on my system) significantly,
+ * most likely due to increased cache misses.
+ */
+ int16_t synced;
+
+};
+
+
+/**
+ * Compare two strings for equality. If either is NULL they are not equal.
+ *
+ * @param s1 first string for comparison.
+ * @param s2 second string for comparison.
+ *
+ * @return 0 if the strings are the same or both NULL, 1 or -1 if not.
+ */
+static int
+sb_nullstrcmp (const struct StringBuffer *s1,
+ const struct StringBuffer *s2)
+{
+ if ( (GNUNET_YES == s1->null_flag) &&
+ (GNUNET_YES == s2->null_flag) )
+ return 0;
+ if ( (GNUNET_YES == s1->null_flag) ||
+ (GNUNET_YES == s2->null_flag) )
+ return -1;
+ if (s1->slen != s2->slen)
+ return -1;
+ return memcmp (s1->sbuf, s2->sbuf, s1->slen);
+}
+
+
+/**
+ * Compare two strings for equality.
+ *
+ * @param s1 first string for comparison.
+ * @param s2 second string for comparison.
+ *
+ * @return 0 if the strings are the same, 1 or -1 if not.
+ */
+static int
+sb_strcmp (const struct StringBuffer *s1,
+ const struct StringBuffer *s2)
+{
+ if (s1->slen != s2->slen)
+ return -1;
+ return memcmp (s1->sbuf, s2->sbuf, s1->slen);
+}
+
+
+/**
+ * Reallocate the buffer of 'ret' to fit 'nlen' characters;
+ * move the existing string to the beginning of the new buffer.
+ *
+ * @param ret current buffer, to be updated
+ * @param nlen target length for the buffer, must be at least ret->slen
+ */
+static void
+sb_realloc (struct StringBuffer *ret,
+ size_t nlen)
+{
+ char *old;
+
+ GNUNET_assert (nlen >= ret->slen);
+ old = ret->abuf;
+ ret->abuf = GNUNET_malloc (nlen);
+ ret->blen = nlen;
+ memcpy (ret->abuf,
+ ret->sbuf,
+ ret->slen);
+ ret->sbuf = ret->abuf;
+ GNUNET_free_non_null (old);
+}
+
+
+/**
+ * Append a string.
+ *
+ * @param ret where to write the result
+ * @param sarg string to append
+ */
+static void
+sb_append (struct StringBuffer *ret,
+ const struct StringBuffer *sarg)
+{
+ if (GNUNET_YES == ret->null_flag)
+ ret->slen = 0;
+ ret->null_flag = GNUNET_NO;
+ if (ret->blen < sarg->slen + ret->slen)
+ sb_realloc (ret, ret->blen + sarg->slen + 128);
+ memcpy (&ret->sbuf[ret->slen],
+ sarg->sbuf,
+ sarg->slen);
+ ret->slen += sarg->slen;
+}
+
+
+/**
+ * Append a C string.
+ *
+ * @param ret where to write the result
+ * @param cstr string to append
+ */
+static void
+sb_append_cstr (struct StringBuffer *ret,
+ const char *cstr)
+{
+ size_t cstr_len = strlen (cstr);
+
+ if (GNUNET_YES == ret->null_flag)
+ ret->slen = 0;
+ ret->null_flag = GNUNET_NO;
+ if (ret->blen < cstr_len + ret->slen)
+ sb_realloc (ret, ret->blen + cstr_len + 128);
+ memcpy (&ret->sbuf[ret->slen],
+ cstr,
+ cstr_len);
+ ret->slen += cstr_len;
+}
+
+
+/**
+ * Wrap a string buffer, that is, set ret to the format string
+ * which contains an "%s" which is to be replaced with the original
+ * content of 'ret'. Note that optimizing this function is not
+ * really worth it, it is rarely called.
+ *
+ * @param ret where to write the result and take the input for %.*s from
+ * @param format format string, fprintf-style, with exactly one "%.*s"
+ * @param extra_chars how long will the result be, in addition to 'sarg' length
+ */
+static void
+sb_wrap (struct StringBuffer *ret,
+ const char *format,
+ size_t extra_chars)
+{
+ char *temp;
+
+ if (GNUNET_YES == ret->null_flag)
+ ret->slen = 0;
+ ret->null_flag = GNUNET_NO;
+ temp = GNUNET_malloc (ret->slen + extra_chars + 1);
+ GNUNET_snprintf (temp,
+ ret->slen + extra_chars + 1,
+ format,
+ (int) ret->slen,
+ ret->sbuf);
+ GNUNET_free_non_null (ret->abuf);
+ ret->abuf = temp;
+ ret->sbuf = temp;
+ ret->blen = ret->slen + extra_chars + 1;
+ ret->slen = ret->slen + extra_chars;
+}
+
+
+/**
+ * Format a string buffer. Note that optimizing this function is not
+ * really worth it, it is rarely called.
+ *
+ * @param ret where to write the result
+ * @param format format string, fprintf-style, with exactly one "%.*s"
+ * @param extra_chars how long will the result be, in addition to 'sarg' length
+ * @param sarg string to print into the format
+ */
+static void
+sb_printf1 (struct StringBuffer *ret,
+ const char *format,
+ size_t extra_chars,
+ const struct StringBuffer *sarg)
+{
+ if (ret->blen < sarg->slen + extra_chars + 1)
+ sb_realloc (ret,
+ sarg->slen + extra_chars + 1);
+ ret->null_flag = GNUNET_NO;
+ ret->sbuf = ret->abuf;
+ ret->slen = sarg->slen + extra_chars;
+ GNUNET_snprintf (ret->sbuf,
+ ret->blen,
+ format,
+ (int) sarg->slen,
+ sarg->sbuf);
+}
+
+
+/**
+ * Format a string buffer.
+ *
+ * @param ret where to write the result
+ * @param format format string, fprintf-style, with exactly two "%.*s"
+ * @param extra_chars how long will the result be, in addition to 'sarg1/2'
length
+ * @param sarg1 first string to print into the format
+ * @param sarg2 second string to print into the format
+ */
+static void
+sb_printf2 (struct StringBuffer *ret,
+ const char *format,
+ size_t extra_chars,
+ const struct StringBuffer *sarg1,
+ const struct StringBuffer *sarg2)
+{
+ if (ret->blen < sarg1->slen + sarg2->slen + extra_chars + 1)
+ sb_realloc (ret,
+ sarg1->slen + sarg2->slen + extra_chars + 1);
+ ret->null_flag = GNUNET_NO;
+ ret->slen = sarg1->slen + sarg2->slen + extra_chars;
+ ret->sbuf = ret->abuf;
+ GNUNET_snprintf (ret->sbuf,
+ ret->blen,
+ format,
+ (int) sarg1->slen,
+ sarg1->sbuf,
+ (int) sarg2->slen,
+ sarg2->sbuf);
+}
+
+
+/**
+ * Format a string buffer. Note that optimizing this function is not
+ * really worth it, it is rarely called.
+ *
+ * @param ret where to write the result
+ * @param format format string, fprintf-style, with exactly three "%.*s"
+ * @param extra_chars how long will the result be, in addition to 'sarg1/2/3'
length
+ * @param sarg1 first string to print into the format
+ * @param sarg2 second string to print into the format
+ * @param sarg3 third string to print into the format
+ */
+static void
+sb_printf3 (struct StringBuffer *ret,
+ const char *format,
+ size_t extra_chars,
+ const struct StringBuffer *sarg1,
+ const struct StringBuffer *sarg2,
+ const struct StringBuffer *sarg3)
+{
+ if (ret->blen < sarg1->slen + sarg2->slen + sarg3->slen + extra_chars + 1)
+ sb_realloc (ret,
+ sarg1->slen + sarg2->slen + sarg3->slen + extra_chars + 1);
+ ret->null_flag = GNUNET_NO;
+ ret->slen = sarg1->slen + sarg2->slen + sarg3->slen + extra_chars;
+ ret->sbuf = ret->abuf;
+ GNUNET_snprintf (ret->sbuf,
+ ret->blen,
+ format,
+ (int) sarg1->slen,
+ sarg1->sbuf,
+ (int) sarg2->slen,
+ sarg2->sbuf,
+ (int) sarg3->slen,
+ sarg3->sbuf);
+}
+
+
+/**
+ * Free resources of the given string buffer.
+ *
+ * @param sb buffer to free (actual pointer is not freed, as they
+ * should not be individually allocated)
+ */
+static void
+sb_free (struct StringBuffer *sb)
+{
+ GNUNET_array_grow (sb->abuf,
+ sb->blen,
+ 0);
+ sb->slen = 0;
+ sb->sbuf = NULL;
+ sb->null_flag= GNUNET_YES;
+}
+
+
+/**
+ * Copy the given string buffer from 'in' to 'out'.
+ *
+ * @param in input string
+ * @param out output string
+ */
+static void
+sb_strdup (struct StringBuffer *out,
+ const struct StringBuffer *in)
+
+{
+ out->null_flag = in->null_flag;
+ if (GNUNET_YES == out->null_flag)
+ return;
+ if (out->blen < in->slen)
+ {
+ GNUNET_array_grow (out->abuf,
+ out->blen,
+ in->slen);
+ }
+ out->sbuf = out->abuf;
+ out->slen = in->slen;
+ memcpy (out->sbuf, in->sbuf, out->slen);
+}
+
+
+/**
+ * Copy the given string buffer from 'in' to 'out'.
+ *
+ * @param cstr input string
+ * @param out output string
+ */
+static void
+sb_strdup_cstr (struct StringBuffer *out,
+ const char *cstr)
+{
+ if (NULL == cstr)
+ {
+ out->null_flag = GNUNET_YES;
+ return;
+ }
+ out->null_flag = GNUNET_NO;
+ out->slen = strlen (cstr);
+ if (out->blen < out->slen)
+ {
+ GNUNET_array_grow (out->abuf,
+ out->blen,
+ out->slen);
+ }
+ out->sbuf = out->abuf;
+ memcpy (out->sbuf, cstr, out->slen);
+}
+
+
+/**
+ * Check if the given string 'str' needs parentheses around it when
+ * using it to generate a regex.
+ *
+ * @param str string
+ *
+ * @return GNUNET_YES if parentheses are needed, GNUNET_NO otherwise
+ */
+static int
+needs_parentheses (const struct StringBuffer *str)
+{
+ size_t slen;
+ const char *op;
+ const char *cl;
+ const char *pos;
+ const char *end;
+ unsigned int cnt;
+
+ if ((GNUNET_YES == str->null_flag) || ((slen = str->slen) < 2))
+ return GNUNET_NO;
+ pos = str->sbuf;
+ if ('(' != pos[0])
+ return GNUNET_YES;
+ end = str->sbuf + slen;
+ cnt = 1;
+ pos++;
+ while (cnt > 0)
+ {
+ cl = memchr (pos, ')', end - pos);
+ if (NULL == cl)
+ {
+ GNUNET_break (0);
+ return GNUNET_YES;
+ }
+ /* while '(' before ')', count opening parens */
+ while ( (NULL != (op = memchr (pos, '(', end - pos))) &&
+ (op < cl) )
+ {
+ cnt++;
+ pos = op + 1;
+ }
+ /* got ')' first */
+ cnt--;
+ pos = cl + 1;
+ }
+ return (*pos == '\0') ? GNUNET_NO : GNUNET_YES;
+}
+
+
+/**
+ * Remove parentheses surrounding string 'str'.
+ * Example: "(a)" becomes "a", "(a|b)|(a|c)" stays the same.
+ * You need to GNUNET_free the returned string.
+ *
+ * @param str string, modified to contain a
+ * @return string without surrounding parentheses, string 'str' if no preceding
+ * epsilon could be found, NULL if 'str' was NULL
+ */
+static void
+remove_parentheses (struct StringBuffer *str)
+{
+ size_t slen;
+ const char *pos;
+ const char *end;
+ const char *sbuf;
+ const char *op;
+ const char *cp;
+ unsigned int cnt;
+
+ if (0)
+ return;
+ sbuf = str->sbuf;
+ if ( (GNUNET_YES == str->null_flag) ||
+ (1 >= (slen = str->slen)) ||
+ ('(' != str->sbuf[0]) ||
+ (')' != str->sbuf[slen - 1]) )
+ return;
+ cnt = 0;
+ pos = &sbuf[1];
+ end = &sbuf[slen - 1];
+ op = memchr (pos, '(', end - pos);
+ cp = memchr (pos, ')', end - pos);
+ while (NULL != cp)
+ {
+ while ( (NULL != op) &&
+ (op < cp) )
+ {
+ cnt++;
+ pos = op + 1;
+ op = memchr (pos, '(', end - pos);
+ }
+ while ( (NULL != cp) &&
+ ( (NULL == op) ||
+ (cp < op) ) )
+ {
+ if (0 == cnt)
+ return; /* can't strip parens */
+ cnt--;
+ pos = cp + 1;
+ cp = memchr (pos, ')', end - pos);
+ }
+ }
+ if (0 != cnt)
+ {
+ GNUNET_break (0);
+ return;
+ }
+ str->sbuf++;
+ str->slen -= 2;
+}
+
+
+/**
+ * Check if the string 'str' starts with an epsilon (empty string).
+ * Example: "(|a)" is starting with an epsilon.
+ *
+ * @param str string to test
+ *
+ * @return 0 if str has no epsilon, 1 if str starts with '(|' and ends with ')'
+ */
+static int
+has_epsilon (const struct StringBuffer *str)
+{
+ return
+ (GNUNET_YES != str->null_flag) &&
+ (0 < str->slen) &&
+ ('(' == str->sbuf[0]) &&
+ ('|' == str->sbuf[1]) &&
+ (')' == str->sbuf[str->slen - 1]);
+}
+
+
+/**
+ * Remove an epsilon from the string str. Where epsilon is an empty string
+ * Example: str = "(|a|b|c)", result: "a|b|c"
+ * The returned string needs to be freed.
+ *
+ * @param str original string
+ * @param ret where to return string without preceding epsilon, string 'str'
if no preceding
+ * epsilon could be found, NULL if 'str' was NULL
+ */
+static void
+remove_epsilon (const struct StringBuffer *str,
+ struct StringBuffer *ret)
+{
+ if (GNUNET_YES == str->null_flag)
+ {
+ ret->null_flag = GNUNET_YES;
+ return;
+ }
+ if ( (str->slen > 1) &&
+ ('(' == str->sbuf[0]) &&
+ ('|' == str->sbuf[1]) &&
+ (')' == str->sbuf[str->slen - 1]) )
+ {
+ /* remove epsilon */
+ if (ret->blen < str->slen - 3)
+ {
+ GNUNET_array_grow (ret->abuf,
+ ret->blen,
+ str->slen - 3);
+ }
+ ret->sbuf = ret->abuf;
+ ret->slen = str->slen - 3;
+ memcpy (ret->sbuf, &str->sbuf[2], ret->slen);
+ return;
+ }
+ sb_strdup (ret, str);
+}
+
+
+/**
+ * Compare n bytes of 'str1' and 'str2'
+ *
+ * @param str1 first string to compare
+ * @param str2 second string for comparison
+ * @param n number of bytes to compare
+ *
+ * @return -1 if any of the strings is NULL, 0 if equal, non 0 otherwise
+ */
+static int
+sb_strncmp (const struct StringBuffer *str1,
+ const struct StringBuffer *str2, size_t n)
+{
+ size_t max;
+
+ if ( (str1->slen != str2->slen) &&
+ ( (str1->slen < n) ||
+ (str2->slen < n) ) )
+ return -1;
+ max = GNUNET_MAX (str1->slen, str2->slen);
+ if (max > n)
+ max = n;
+ return memcmp (str1->sbuf, str2->sbuf, max);
+}
+
+
+/**
+ * Compare n bytes of 'str1' and 'str2'
+ *
+ * @param str1 first string to compare
+ * @param str2 second C string for comparison
+ * @param n number of bytes to compare (and length of str2)
+ *
+ * @return -1 if any of the strings is NULL, 0 if equal, non 0 otherwise
+ */
+static int
+sb_strncmp_cstr (const struct StringBuffer *str1,
+ const char *str2, size_t n)
+{
+ if (str1->slen < n)
+ return -1;
+ return memcmp (str1->sbuf, str2, n);
+}
+
+
+/**
+ * Initialize string buffer for storing strings of up to n
+ * characters.
+ *
+ * @param sb buffer to initialize
+ * @param n desired target length
+ */
+static void
+sb_init (struct StringBuffer *sb,
+ size_t n)
+{
+ sb->null_flag = GNUNET_NO;
+ sb->abuf = sb->sbuf = (0 == n) ? NULL : GNUNET_malloc (n);
+ sb->blen = n;
+ sb->slen = 0;
+}
+
+
+/**
+ * Compare 'str1', starting from position 'k', with whole 'str2'
+ *
+ * @param str1 first string to compare, starting from position 'k'
+ * @param str2 second string for comparison
+ * @param k starting position in 'str1'
+ *
+ * @return -1 if any of the strings is NULL, 0 if equal, non 0 otherwise
+ */
+static int
+sb_strkcmp (const struct StringBuffer *str1,
+ const struct StringBuffer *str2, size_t k)
+{
+ if ( (GNUNET_YES == str1->null_flag) ||
+ (GNUNET_YES == str2->null_flag) ||
+ (k > str1->slen) ||
+ (str1->slen - k != str2->slen) )
+ return -1;
+ return memcmp (&str1->sbuf[k], str2->sbuf, str2->slen);
+}
+
+
+/**
+ * Helper function used as 'action' in 'REGEX_ITERNAL_automaton_traverse'
+ * function to create the depth-first numbering of the states.
+ *
+ * @param cls states array.
+ * @param count current state counter.
+ * @param s current state.
+ */
+static void
+number_states (void *cls, const unsigned int count,
+ struct REGEX_ITERNAL_State *s)
+{
+ struct REGEX_ITERNAL_State **states = cls;
+
+ s->dfs_id = count;
+ if (NULL != states)
+ states[count] = s;
+}
+
+
+
+#define PRIS(a) \
+ ((GNUNET_YES == a.null_flag) ? 6 : (int) a.slen), \
+ ((GNUNET_YES == a.null_flag) ? "(null)" : a.sbuf)
+
+
+/**
+ * Construct the regular expression given the inductive step,
+ * $R^{(k)}_{ij} = R^{(k-1)}_{ij} | R^{(k-1)}_{ik} ( R^{(k-1)}_{kk} )^*
+ * R^{(k-1)}_{kj}, and simplify the resulting expression saved in R_cur_ij.
+ *
+ * @param R_last_ij value of $R^{(k-1)_{ij}.
+ * @param R_last_ik value of $R^{(k-1)_{ik}.
+ * @param R_last_kk value of $R^{(k-1)_{kk}.
+ * @param R_last_kj value of $R^{(k-1)_{kj}.
+ * @param R_cur_ij result for this inductive step is saved in R_cur_ij,
R_cur_ij
+ * is expected to be NULL when called!
+ * @param R_cur_l optimization -- kept between iterations to avoid realloc
+ * @param R_cur_r optimization -- kept between iterations to avoid realloc
+ */
+static void
+automaton_create_proofs_simplify (const struct StringBuffer *R_last_ij,
+ const struct StringBuffer *R_last_ik,
+ const struct StringBuffer *R_last_kk,
+ const struct StringBuffer *R_last_kj,
+ struct StringBuffer *R_cur_ij,
+ struct StringBuffer *R_cur_l,
+ struct StringBuffer *R_cur_r)
+{
+ struct StringBuffer R_temp_ij;
+ struct StringBuffer R_temp_ik;
+ struct StringBuffer R_temp_kj;
+ struct StringBuffer R_temp_kk;
+ int eps_check;
+ int ij_ik_cmp;
+ int ij_kj_cmp;
+ int ik_kk_cmp;
+ int kk_kj_cmp;
+ int clean_ik_kk_cmp;
+ int clean_kk_kj_cmp;
+ size_t length;
+ size_t length_l;
+ size_t length_r;
+
+ /*
+ * $R^{(k)}_{ij} = R^{(k-1)}_{ij} | R^{(k-1)}_{ik} ( R^{(k-1)}_{kk} )^*
R^{(k-1)}_{kj}
+ * R_last == R^{(k-1)}, R_cur == R^{(k)}
+ * R_cur_ij = R_cur_l | R_cur_r
+ * R_cur_l == R^{(k-1)}_{ij}
+ * R_cur_r == R^{(k-1)}_{ik} ( R^{(k-1)}_{kk} )^* R^{(k-1)}_{kj}
+ */
+
+ if ( (GNUNET_YES == R_last_ij->null_flag) &&
+ ( (GNUNET_YES == R_last_ik->null_flag) ||
+ (GNUNET_YES == R_last_kj->null_flag)))
+ {
+ /* R^{(k)}_{ij} = N | N */
+ R_cur_ij->null_flag = GNUNET_YES;
+ R_cur_ij->synced = GNUNET_NO;
+ return;
+ }
+
+ if ( (GNUNET_YES == R_last_ik->null_flag) ||
+ (GNUNET_YES == R_last_kj->null_flag) )
+ {
+ /* R^{(k)}_{ij} = R^{(k-1)}_{ij} | N */
+ if (GNUNET_YES == R_last_ij->synced)
+ {
+ R_cur_ij->synced = GNUNET_YES;
+ R_cur_ij->null_flag = GNUNET_NO;
+ return;
+ }
+ R_cur_ij->synced = GNUNET_YES;
+ sb_strdup (R_cur_ij, R_last_ij);
+ return;
+ }
+ R_cur_ij->synced = GNUNET_NO;
+
+ /* $R^{(k)}_{ij} = N | R^{(k-1)}_{ik} ( R^{(k-1)}_{kk} )^* R^{(k-1)}_{kj} OR
+ * $R^{(k)}_{ij} = R^{(k-1)}_{ij} | R^{(k-1)}_{ik} ( R^{(k-1)}_{kk} )^*
R^{(k-1)}_{kj} */
+
+ R_cur_r->null_flag = GNUNET_YES;
+ R_cur_r->slen = 0;
+ R_cur_l->null_flag = GNUNET_YES;
+ R_cur_l->slen = 0;
+
+ /* cache results from strcmp, we might need these many times */
+ ij_kj_cmp = sb_nullstrcmp (R_last_ij, R_last_kj);
+ ij_ik_cmp = sb_nullstrcmp (R_last_ij, R_last_ik);
+ ik_kk_cmp = sb_nullstrcmp (R_last_ik, R_last_kk);
+ kk_kj_cmp = sb_nullstrcmp (R_last_kk, R_last_kj);
+
+ /* Assign R_temp_(ik|kk|kj) to R_last[][] and remove epsilon as well
+ * as parentheses, so we can better compare the contents */
+
+ memset (&R_temp_ij, 0, sizeof (struct StringBuffer));
+ memset (&R_temp_ik, 0, sizeof (struct StringBuffer));
+ memset (&R_temp_kk, 0, sizeof (struct StringBuffer));
+ memset (&R_temp_kj, 0, sizeof (struct StringBuffer));
+ remove_epsilon (R_last_ik, &R_temp_ik);
+ remove_epsilon (R_last_kk, &R_temp_kk);
+ remove_epsilon (R_last_kj, &R_temp_kj);
+ remove_parentheses (&R_temp_ik);
+ remove_parentheses (&R_temp_kk);
+ remove_parentheses (&R_temp_kj);
+ clean_ik_kk_cmp = sb_nullstrcmp (R_last_ik, &R_temp_kk);
+ clean_kk_kj_cmp = sb_nullstrcmp (&R_temp_kk, R_last_kj);
+
+ /* construct R_cur_l (and, if necessary R_cur_r) */
+ if (GNUNET_YES != R_last_ij->null_flag)
+ {
+ /* Assign R_temp_ij to R_last_ij and remove epsilon as well
+ * as parentheses, so we can better compare the contents */
+ remove_epsilon (R_last_ij, &R_temp_ij);
+ remove_parentheses (&R_temp_ij);
+
+ if ( (0 == sb_strcmp (&R_temp_ij, &R_temp_ik)) &&
+ (0 == sb_strcmp (&R_temp_ik, &R_temp_kk)) &&
+ (0 == sb_strcmp (&R_temp_kk, &R_temp_kj)) )
+ {
+ if (0 == R_temp_ij.slen)
+ {
+ R_cur_r->null_flag = GNUNET_NO;
+ }
+ else if ((0 == sb_strncmp_cstr (R_last_ij, "(|", 2)) ||
+ (0 == sb_strncmp_cstr (R_last_ik, "(|", 2) &&
+ 0 == sb_strncmp_cstr (R_last_kj, "(|", 2)))
+ {
+ /*
+ * a|(e|a)a*(e|a) = a*
+ * a|(e|a)(e|a)*(e|a) = a*
+ * (e|a)|aa*a = a*
+ * (e|a)|aa*(e|a) = a*
+ * (e|a)|(e|a)a*a = a*
+ * (e|a)|(e|a)a*(e|a) = a*
+ * (e|a)|(e|a)(e|a)*(e|a) = a*
+ */
+ if (GNUNET_YES == needs_parentheses (&R_temp_ij))
+ sb_printf1 (R_cur_r, "(%.*s)*", 3, &R_temp_ij);
+ else
+ sb_printf1 (R_cur_r, "%.*s*", 1, &R_temp_ij);
+ }
+ else
+ {
+ /*
+ * a|aa*a = a+
+ * a|(e|a)a*a = a+
+ * a|aa*(e|a) = a+
+ * a|(e|a)(e|a)*a = a+
+ * a|a(e|a)*(e|a) = a+
+ */
+ if (GNUNET_YES == needs_parentheses (&R_temp_ij))
+ sb_printf1 (R_cur_r, "(%.*s)+", 3, &R_temp_ij);
+ else
+ sb_printf1 (R_cur_r, "%.*s+", 1, &R_temp_ij);
+ }
+ }
+ else if ( (0 == ij_ik_cmp) && (0 == clean_kk_kj_cmp) && (0 !=
clean_ik_kk_cmp) )
+ {
+ /* a|ab*b = ab* */
+ if (0 == R_last_kk->slen)
+ sb_strdup (R_cur_r, R_last_ij);
+ else if (GNUNET_YES == needs_parentheses (&R_temp_kk))
+ sb_printf2 (R_cur_r, "%.*s(%.*s)*", 3, R_last_ij, &R_temp_kk);
+ else
+ sb_printf2 (R_cur_r, "%.*s%.*s*", 1, R_last_ij, R_last_kk);
+ R_cur_l->null_flag = GNUNET_YES;
+ }
+ else if ( (0 == ij_kj_cmp) && (0 == clean_ik_kk_cmp) && (0 !=
clean_kk_kj_cmp))
+ {
+ /* a|bb*a = b*a */
+ if (R_last_kk->slen < 1)
+ {
+ sb_strdup (R_cur_r, R_last_kj);
+ }
+ else if (GNUNET_YES == needs_parentheses (&R_temp_kk))
+ sb_printf2 (R_cur_r, "(%.*s)*%.*s", 3, &R_temp_kk, R_last_kj);
+ else
+ sb_printf2 (R_cur_r, "%.*s*%.*s", 1, &R_temp_kk, R_last_kj);
+
+ R_cur_l->null_flag = GNUNET_YES;
+ }
+ else if ( (0 == ij_ik_cmp) && (0 == kk_kj_cmp) && (! has_epsilon
(R_last_ij)) &&
+ has_epsilon (R_last_kk))
+ {
+ /* a|a(e|b)*(e|b) = a|ab* = a|a|ab|abb|abbb|... = ab* */
+ if (needs_parentheses (&R_temp_kk))
+ sb_printf2 (R_cur_r, "%.*s(%.*s)*", 3, R_last_ij, &R_temp_kk);
+ else
+ sb_printf2 (R_cur_r, "%.*s%.*s*", 1, R_last_ij, &R_temp_kk);
+ R_cur_l->null_flag = GNUNET_YES;
+ }
+ else if ( (0 == ij_kj_cmp) && (0 == ik_kk_cmp) && (! has_epsilon
(R_last_ij)) &&
+ has_epsilon (R_last_kk))
+ {
+ /* a|(e|b)(e|b)*a = a|b*a = a|a|ba|bba|bbba|... = b*a */
+ if (needs_parentheses (&R_temp_kk))
+ sb_printf2 (R_cur_r, "(%.*s)*%.*s", 3, &R_temp_kk, R_last_ij);
+ else
+ sb_printf2 (R_cur_r, "%.*s*%.*s", 1, &R_temp_kk, R_last_ij);
+ R_cur_l->null_flag = GNUNET_YES;
+ }
+ else
+ {
+ sb_strdup (R_cur_l, R_last_ij);
+ remove_parentheses (R_cur_l);
+ }
+ }
+ else
+ {
+ /* we have no left side */
+ R_cur_l->null_flag = GNUNET_YES;
+ }
+
+ /* construct R_cur_r, if not already constructed */
+ if (GNUNET_YES == R_cur_r->null_flag)
+ {
+ length = R_temp_kk.slen - R_last_ik->slen;
+
+ /* a(ba)*bx = (ab)+x */
+ if ( (length > 0) &&
+ (GNUNET_YES != R_last_kk->null_flag) &&
+ (0 < R_last_kk->slen) &&
+ (GNUNET_YES != R_last_kj->null_flag) &&
+ (0 < R_last_kj->slen) &&
+ (GNUNET_YES != R_last_ik->null_flag) &&
+ (0 < R_last_ik->slen) &&
+ (0 == sb_strkcmp (&R_temp_kk, R_last_ik, length)) &&
+ (0 == sb_strncmp (&R_temp_kk, R_last_kj, length)) )
+ {
+ struct StringBuffer temp_a;
+ struct StringBuffer temp_b;
+
+ sb_init (&temp_a, length);
+ sb_init (&temp_b, R_last_kj->slen - length);
+
+ length_l = length;
+ temp_a.sbuf = temp_a.abuf;
+ memcpy (temp_a.sbuf, R_last_kj->sbuf, length_l);
+ temp_a.slen = length_l;
+
+ length_r = R_last_kj->slen - length;
+ temp_b.sbuf = temp_b.abuf;
+ memcpy (temp_b.sbuf, &R_last_kj->sbuf[length], length_r);
+ temp_b.slen = length_r;
+
+ /* e|(ab)+ = (ab)* */
+ if ( (GNUNET_YES != R_cur_l->null_flag) &&
+ (0 == R_cur_l->slen) &&
+ (0 == temp_b.slen) )
+ {
+ sb_printf2 (R_cur_r, "(%.*s%.*s)*", 3, R_last_ik, &temp_a);
+ sb_free (R_cur_l);
+ R_cur_l->null_flag = GNUNET_YES;
+ }
+ else
+ {
+ sb_printf3 (R_cur_r, "(%.*s%.*s)+%.*s", 3, R_last_ik, &temp_a,
&temp_b);
+ }
+ sb_free (&temp_a);
+ sb_free (&temp_b);
+ }
+ else if (0 == sb_strcmp (&R_temp_ik, &R_temp_kk) &&
+ 0 == sb_strcmp (&R_temp_kk, &R_temp_kj))
+ {
+ /*
+ * (e|a)a*(e|a) = a*
+ * (e|a)(e|a)*(e|a) = a*
+ */
+ if (has_epsilon (R_last_ik) && has_epsilon (R_last_kj))
+ {
+ if (needs_parentheses (&R_temp_kk))
+ sb_printf1 (R_cur_r, "(%.*s)*", 3, &R_temp_kk);
+ else
+ sb_printf1 (R_cur_r, "%.*s*", 1, &R_temp_kk);
+ }
+ /* aa*a = a+a */
+ else if ( (0 == clean_ik_kk_cmp) &&
+ (0 == clean_kk_kj_cmp) &&
+ (! has_epsilon (R_last_ik)) )
+ {
+ if (needs_parentheses (&R_temp_kk))
+ sb_printf2 (R_cur_r, "(%.*s)+%.*s", 3, &R_temp_kk, &R_temp_kk);
+ else
+ sb_printf2 (R_cur_r, "%.*s+%.*s", 1, &R_temp_kk, &R_temp_kk);
+ }
+ /*
+ * (e|a)a*a = a+
+ * aa*(e|a) = a+
+ * a(e|a)*(e|a) = a+
+ * (e|a)a*a = a+
+ */
+ else
+ {
+ eps_check =
+ (has_epsilon (R_last_ik) + has_epsilon (R_last_kk) +
+ has_epsilon (R_last_kj));
+
+ if (1 == eps_check)
+ {
+ if (needs_parentheses (&R_temp_kk))
+ sb_printf1 (R_cur_r, "(%.*s)+", 3, &R_temp_kk);
+ else
+ sb_printf1 (R_cur_r, "%.*s+", 1, &R_temp_kk);
+ }
+ }
+ }
+ /*
+ * aa*b = a+b
+ * (e|a)(e|a)*b = a*b
+ */
+ else if (0 == sb_strcmp (&R_temp_ik, &R_temp_kk))
+ {
+ if (has_epsilon (R_last_ik))
+ {
+ if (needs_parentheses (&R_temp_kk))
+ sb_printf2 (R_cur_r, "(%.*s)*%.*s", 3, &R_temp_kk, R_last_kj);
+ else
+ sb_printf2 (R_cur_r, "%.*s*%.*s", 1, &R_temp_kk, R_last_kj);
+ }
+ else
+ {
+ if (needs_parentheses (&R_temp_kk))
+ sb_printf2 (R_cur_r, "(%.*s)+%.*s", 3, &R_temp_kk, R_last_kj);
+ else
+ sb_printf2 (R_cur_r, "%.*s+%.*s", 1, &R_temp_kk, R_last_kj);
+ }
+ }
+ /*
+ * ba*a = ba+
+ * b(e|a)*(e|a) = ba*
+ */
+ else if (0 == sb_strcmp (&R_temp_kk, &R_temp_kj))
+ {
+ if (has_epsilon (R_last_kj))
+ {
+ if (needs_parentheses (&R_temp_kk))
+ sb_printf2 (R_cur_r, "%.*s(%.*s)*", 3, R_last_ik, &R_temp_kk);
+ else
+ sb_printf2 (R_cur_r, "%.*s%.*s*", 1, R_last_ik, &R_temp_kk);
+ }
+ else
+ {
+ if (needs_parentheses (&R_temp_kk))
+ sb_printf2 (R_cur_r, "(%.*s)+%.*s", 3, R_last_ik, &R_temp_kk);
+ else
+ sb_printf2 (R_cur_r, "%.*s+%.*s", 1, R_last_ik, &R_temp_kk);
+ }
+ }
+ else
+ {
+ if (0 < R_temp_kk.slen)
+ {
+ if (needs_parentheses (&R_temp_kk))
+ {
+ sb_printf3 (R_cur_r, "%.*s(%.*s)*%.*s", 3, R_last_ik, &R_temp_kk,
+ R_last_kj);
+ }
+ else
+ {
+ sb_printf3 (R_cur_r, "%.*s%.*s*%.*s", 1, R_last_ik, &R_temp_kk,
+ R_last_kj);
+ }
+ }
+ else
+ {
+ sb_printf2 (R_cur_r, "%.*s%.*s", 0, R_last_ik, R_last_kj);
+ }
+ }
+ }
+ sb_free (&R_temp_ij);
+ sb_free (&R_temp_ik);
+ sb_free (&R_temp_kk);
+ sb_free (&R_temp_kj);
+
+ if ( (GNUNET_YES == R_cur_l->null_flag) &&
+ (GNUNET_YES == R_cur_r->null_flag) )
+ {
+ R_cur_ij->null_flag = GNUNET_YES;
+ return;
+ }
+
+ if ( (GNUNET_YES != R_cur_l->null_flag) &&
+ (GNUNET_YES == R_cur_r->null_flag) )
+ {
+ struct StringBuffer tmp;
+
+ tmp = *R_cur_ij;
+ *R_cur_ij = *R_cur_l;
+ *R_cur_l = tmp;
+ return;
+ }
+
+ if ( (GNUNET_YES == R_cur_l->null_flag) &&
+ (GNUNET_YES != R_cur_r->null_flag) )
+ {
+ struct StringBuffer tmp;
+
+ tmp = *R_cur_ij;
+ *R_cur_ij = *R_cur_r;
+ *R_cur_r = tmp;
+ return;
+ }
+
+ if (0 == sb_nullstrcmp (R_cur_l, R_cur_r))
+ {
+ struct StringBuffer tmp;
+
+ tmp = *R_cur_ij;
+ *R_cur_ij = *R_cur_l;
+ *R_cur_l = tmp;
+ return;
+ }
+ sb_printf2 (R_cur_ij, "(%.*s|%.*s)", 3, R_cur_l, R_cur_r);
+}
+
+
+/**
+ * Create proofs for all states in the given automaton. Implementation of the
+ * algorithm descriped in chapter 3.2.1 of "Automata Theory, Languages, and
+ * Computation 3rd Edition" by Hopcroft, Motwani and Ullman.
+ *
+ * Each state in the automaton gets assigned 'proof' and 'hash' (hash of the
+ * proof) fields. The starting state will only have a valid proof/hash if it
has
+ * any incoming transitions.
+ *
+ * @param a automaton for which to assign proofs and hashes, must not be NULL
+ */
+static int
+automaton_create_proofs (struct REGEX_ITERNAL_Automaton *a)
+{
+ unsigned int n = a->state_count;
+ struct REGEX_ITERNAL_State *states[n];
+ struct StringBuffer *R_last;
+ struct StringBuffer *R_cur;
+ struct StringBuffer R_cur_r;
+ struct StringBuffer R_cur_l;
+ struct StringBuffer *R_swap;
+ struct REGEX_ITERNAL_Transition *t;
+ struct StringBuffer complete_regex;
+ unsigned int i;
+ unsigned int j;
+ unsigned int k;
+
+ R_last = GNUNET_malloc_large (sizeof (struct StringBuffer) * n * n);
+ R_cur = GNUNET_malloc_large (sizeof (struct StringBuffer) * n * n);
+ if ( (NULL == R_last) ||
+ (NULL == R_cur) )
+ {
+ GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "malloc");
+ GNUNET_free_non_null (R_cur);
+ GNUNET_free_non_null (R_last);
+ return GNUNET_SYSERR;
+ }
+
+ /* create depth-first numbering of the states, initializes 'state' */
+ REGEX_ITERNAL_automaton_traverse (a, a->start, NULL, NULL, &number_states,
+ states);
+
+ for (i = 0; i < n; i++)
+ GNUNET_assert (NULL != states[i]);
+ for (i = 0; i < n; i++)
+ for (j = 0; j < n; j++)
+ R_last[i *n + j].null_flag = GNUNET_YES;
+
+ /* Compute regular expressions of length "1" between each pair of states */
+ for (i = 0; i < n; i++)
+ {
+ for (t = states[i]->transitions_head; NULL != t; t = t->next)
+ {
+ j = t->to_state->dfs_id;
+ if (GNUNET_YES == R_last[i * n + j].null_flag)
+ {
+ sb_strdup_cstr (&R_last[i * n + j], t->label);
+ }
+ else
+ {
+ sb_append_cstr (&R_last[i * n + j], "|");
+ sb_append_cstr (&R_last[i * n + j], t->label);
+ }
+ }
+ /* add self-loop: i is reachable from i via epsilon-transition */
+ if (GNUNET_YES == R_last[i * n + i].null_flag)
+ {
+ R_last[i * n + i].slen = 0;
+ R_last[i * n + i].null_flag = GNUNET_NO;
+ }
+ else
+ {
+ sb_wrap (&R_last[i * n + i], "(|%.*s)", 3);
+ }
+ }
+ for (i = 0; i < n; i++)
+ for (j = 0; j < n; j++)
+ if (needs_parentheses (&R_last[i * n + j]))
+ sb_wrap (&R_last[i * n + j], "(%.*s)", 2);
+ /* Compute regular expressions of length "k" between each pair of states per
+ * induction */
+ memset (&R_cur_l, 0, sizeof (struct StringBuffer));
+ memset (&R_cur_r, 0, sizeof (struct StringBuffer));
+ for (k = 0; k < n; k++)
+ {
+ for (i = 0; i < n; i++)
+ {
+ for (j = 0; j < n; j++)
+ {
+ /* Basis for the recursion:
+ * $R^{(k)}_{ij} = R^{(k-1)}_{ij} | R^{(k-1)}_{ik} ( R^{(k-1)}_{kk}
)^* R^{(k-1)}_{kj}
+ * R_last == R^{(k-1)}, R_cur == R^{(k)}
+ */
+
+ /* Create R_cur[i][j] and simplify the expression */
+ automaton_create_proofs_simplify (&R_last[i * n + j], &R_last[i * n +
k],
+ &R_last[k * n + k], &R_last[k * n +
j],
+ &R_cur[i * n + j],
+ &R_cur_l, &R_cur_r);
+ }
+ }
+ /* set R_last = R_cur */
+ R_swap = R_last;
+ R_last = R_cur;
+ R_cur = R_swap;
+ /* clear 'R_cur' for next iteration */
+ for (i = 0; i < n; i++)
+ for (j = 0; j < n; j++)
+ R_cur[i * n + j].null_flag = GNUNET_YES;
+ }
+ sb_free (&R_cur_l);
+ sb_free (&R_cur_r);
+ /* assign proofs and hashes */
+ for (i = 0; i < n; i++)
+ {
+ if (GNUNET_YES != R_last[a->start->dfs_id * n + i].null_flag)
+ {
+ states[i]->proof = GNUNET_strndup (R_last[a->start->dfs_id * n + i].sbuf,
+ R_last[a->start->dfs_id * n + i].slen);
+ GNUNET_CRYPTO_hash (states[i]->proof, strlen (states[i]->proof),
+ &states[i]->hash);
+ }
+ }
+
+ /* complete regex for whole DFA: union of all pairs (start state/accepting
+ * state(s)). */
+ sb_init (&complete_regex, 16 * n);
+ for (i = 0; i < n; i++)
+ {
+ if (states[i]->accepting)
+ {
+ if ( (0 == complete_regex.slen) &&
+ (0 < R_last[a->start->dfs_id * n + i].slen) )
+ {
+ sb_append (&complete_regex,
+ &R_last[a->start->dfs_id * n + i]);
+ }
+ else if ( (GNUNET_YES != R_last[a->start->dfs_id * n + i].null_flag) &&
+ (0 < R_last[a->start->dfs_id * n + i].slen) )
+ {
+ sb_append_cstr (&complete_regex, "|");
+ sb_append (&complete_regex,
+ &R_last[a->start->dfs_id * n + i]);
+ }
+ }
+ }
+ a->canonical_regex = GNUNET_strndup (complete_regex.sbuf,
complete_regex.slen);
+
+ /* cleanup */
+ sb_free (&complete_regex);
+ for (i = 0; i < n; i++)
+ for (j = 0; j < n; j++)
+ {
+ sb_free (&R_cur[i * n + j]);
+ sb_free (&R_last[i * n + j]);
+ }
+ GNUNET_free (R_cur);
+ GNUNET_free (R_last);
+ return GNUNET_OK;
+}
+
+
+/**
+ * Creates a new DFA state based on a set of NFA states. Needs to be freed
using
+ * automaton_destroy_state.
+ *
+ * @param ctx context
+ * @param nfa_states set of NFA states on which the DFA should be based on
+ *
+ * @return new DFA state
+ */
+static struct REGEX_ITERNAL_State *
+dfa_state_create (struct REGEX_ITERNAL_Context *ctx,
+ struct REGEX_ITERNAL_StateSet *nfa_states)
+{
+ struct REGEX_ITERNAL_State *s;
+ char *pos;
+ size_t len;
+ struct REGEX_ITERNAL_State *cstate;
+ struct REGEX_ITERNAL_Transition *ctran;
+ unsigned int i;
+
+ s = GNUNET_malloc (sizeof (struct REGEX_ITERNAL_State));
+ s->id = ctx->state_id++;
+ s->index = -1;
+ s->lowlink = -1;
+
+ if (NULL == nfa_states)
+ {
+ GNUNET_asprintf (&s->name, "s%i", s->id);
+ return s;
+ }
+
+ s->nfa_set = *nfa_states;
+
+ if (nfa_states->off < 1)
+ return s;
+
+ /* Create a name based on 'nfa_states' */
+ len = nfa_states->off * 14 + 4;
+ s->name = GNUNET_malloc (len);
+ strcat (s->name, "{");
+ pos = s->name + 1;
+
+ for (i = 0; i < nfa_states->off; i++)
+ {
+ cstate = nfa_states->states[i];
+ GNUNET_snprintf (pos, pos - s->name + len,
+ "%i,", cstate->id);
+ pos += strlen (pos);
+
+ /* Add a transition for each distinct label to NULL state */
+ for (ctran = cstate->transitions_head; NULL != ctran; ctran = ctran->next)
+ if (NULL != ctran->label)
+ state_add_transition (ctx, s, ctran->label, NULL);
+
+ /* If the nfa_states contain an accepting state, the new dfa state is also
+ * accepting. */
+ if (cstate->accepting)
+ s->accepting = 1;
+ }
+ pos[-1] = '}';
+ s->name = GNUNET_realloc (s->name, strlen (s->name) + 1);
+
+ memset (nfa_states, 0, sizeof (struct REGEX_ITERNAL_StateSet));
+ return s;
+}
+
+
+/**
+ * Move from the given state 's' to the next state on transition 'str'.
Consumes
+ * as much of the given 'str' as possible (usefull for strided DFAs). On return
+ * 's' will point to the next state, and the length of the substring used for
+ * this transition will be returned. If no transition possible 0 is returned
and
+ * 's' points to NULL.
+ *
+ * @param s starting state, will point to the next state or NULL (if no
+ * transition possible)
+ * @param str edge label to follow (will match longest common prefix)
+ *
+ * @return length of the substring comsumed from 'str'
+ */
+static unsigned int
+dfa_move (struct REGEX_ITERNAL_State **s, const char *str)
+{
+ struct REGEX_ITERNAL_Transition *t;
+ struct REGEX_ITERNAL_State *new_s;
+ unsigned int len;
+ unsigned int max_len;
+
+ if (NULL == s)
+ return 0;
+
+ new_s = NULL;
+ max_len = 0;
+ for (t = (*s)->transitions_head; NULL != t; t = t->next)
+ {
+ len = strlen (t->label);
+
+ if (0 == strncmp (t->label, str, len))
+ {
+ if (len >= max_len)
+ {
+ max_len = len;
+ new_s = t->to_state;
+ }
+ }
+ }
+
+ *s = new_s;
+ return max_len;
+}
+
+
+/**
+ * Set the given state 'marked' to GNUNET_YES. Used by the
+ * 'dfa_remove_unreachable_states' function to detect unreachable states in the
+ * automaton.
+ *
+ * @param cls closure, not used.
+ * @param count count, not used.
+ * @param s state where the marked attribute will be set to GNUNET_YES.
+ */
+static void
+mark_states (void *cls, const unsigned int count, struct REGEX_ITERNAL_State
*s)
+{
+ s->marked = GNUNET_YES;
+}
+
+
+/**
+ * Remove all unreachable states from DFA 'a'. Unreachable states are those
+ * states that are not reachable from the starting state.
+ *
+ * @param a DFA automaton
+ */
+static void
+dfa_remove_unreachable_states (struct REGEX_ITERNAL_Automaton *a)
+{
+ struct REGEX_ITERNAL_State *s;
+ struct REGEX_ITERNAL_State *s_next;
+
+ /* 1. unmark all states */
+ for (s = a->states_head; NULL != s; s = s->next)
+ s->marked = GNUNET_NO;
+
+ /* 2. traverse dfa from start state and mark all visited states */
+ REGEX_ITERNAL_automaton_traverse (a, a->start, NULL, NULL, &mark_states,
NULL);
+
+ /* 3. delete all states that were not visited */
+ for (s = a->states_head; NULL != s; s = s_next)
+ {
+ s_next = s->next;
+ if (GNUNET_NO == s->marked)
+ automaton_remove_state (a, s);
+ }
+}
+
+
+/**
+ * Remove all dead states from the DFA 'a'. Dead states are those states that
do
+ * not transition to any other state but themselves.
+ *
+ * @param a DFA automaton
+ */
+static void
+dfa_remove_dead_states (struct REGEX_ITERNAL_Automaton *a)
+{
+ struct REGEX_ITERNAL_State *s;
+ struct REGEX_ITERNAL_State *s_next;
+ struct REGEX_ITERNAL_Transition *t;
+ int dead;
+
+ GNUNET_assert (DFA == a->type);
+
+ for (s = a->states_head; NULL != s; s = s_next)
+ {
+ s_next = s->next;
+
+ if (s->accepting)
+ continue;
+
+ dead = 1;
+ for (t = s->transitions_head; NULL != t; t = t->next)
+ {
+ if (NULL != t->to_state && t->to_state != s)
+ {
+ dead = 0;
+ break;
+ }
+ }
+
+ if (0 == dead)
+ continue;
+
+ /* state s is dead, remove it */
+ automaton_remove_state (a, s);
+ }
+}
+
+
+/**
+ * Merge all non distinguishable states in the DFA 'a'
+ *
+ * @param ctx context
+ * @param a DFA automaton
+ * @return GNUNET_OK on success
+ */
+static int
+dfa_merge_nondistinguishable_states (struct REGEX_ITERNAL_Context *ctx,
+ struct REGEX_ITERNAL_Automaton *a)
+{
+ uint32_t *table;
+ struct REGEX_ITERNAL_State *s1;
+ struct REGEX_ITERNAL_State *s2;
+ struct REGEX_ITERNAL_Transition *t1;
+ struct REGEX_ITERNAL_Transition *t2;
+ struct REGEX_ITERNAL_State *s1_next;
+ struct REGEX_ITERNAL_State *s2_next;
+ int change;
+ unsigned int num_equal_edges;
+ unsigned int i;
+ unsigned int state_cnt;
+ unsigned long long idx;
+ unsigned long long idx1;
+
+ if ( (NULL == a) || (0 == a->state_count) )
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "Could not merge nondistinguishable states, automaton was
NULL.\n");
+ return GNUNET_SYSERR;
+ }
+
+ state_cnt = a->state_count;
+ table = GNUNET_malloc_large ((sizeof (uint32_t) * state_cnt * state_cnt /
32) + sizeof (uint32_t));
+ if (NULL == table)
+ {
+ GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "malloc");
+ return GNUNET_SYSERR;
+ }
+
+ for (i = 0, s1 = a->states_head; NULL != s1; s1 = s1->next)
+ s1->marked = i++;
+
+ /* Mark all pairs of accepting/!accepting states */
+ for (s1 = a->states_head; NULL != s1; s1 = s1->next)
+ for (s2 = a->states_head; NULL != s2; s2 = s2->next)
+ if ( (s1->accepting && !s2->accepting) ||
+ (!s1->accepting && s2->accepting) )
+ {
+ idx = s1->marked * state_cnt + s2->marked;
+ table[idx / 32] |= (1 << (idx % 32));
+ }
+
+ /* Find all equal states */
+ change = 1;
+ while (0 != change)
+ {
+ change = 0;
+ for (s1 = a->states_head; NULL != s1; s1 = s1->next)
+ {
+ for (s2 = a->states_head; NULL != s2 && s1 != s2; s2 = s2->next)
+ {
+ idx = s1->marked * state_cnt + s2->marked;
+ if (0 != (table[idx / 32] & (1 << (idx % 32))))
+ continue;
+ num_equal_edges = 0;
+ for (t1 = s1->transitions_head; NULL != t1; t1 = t1->next)
+ {
+ for (t2 = s2->transitions_head; NULL != t2; t2 = t2->next)
+ {
+ if (0 == strcmp (t1->label, t2->label))
+ {
+ num_equal_edges++;
+ /* same edge, but targets definitively different, so we're
different
+ as well */
+ if (t1->to_state->marked > t2->to_state->marked)
+ idx1 = t1->to_state->marked * state_cnt + t2->to_state->marked;
+ else
+ idx1 = t2->to_state->marked * state_cnt + t1->to_state->marked;
+ if (0 != (table[idx1 / 32] & (1 << (idx1 % 32))))
+ {
+ table[idx / 32] |= (1 << (idx % 32));
+ change = 1; /* changed a marker, need to run again */
+ }
+ }
+ }
+ }
+ if ( (num_equal_edges != s1->transition_count) ||
+ (num_equal_edges != s2->transition_count) )
+ {
+ /* Make sure ALL edges of possible equal states are the same */
+ table[idx / 32] |= (1 << (idx % 32));
+ change = 1; /* changed a marker, need to run again */
+ }
+ }
+ }
+ }
+
+ /* Merge states that are equal */
+ for (s1 = a->states_head; NULL != s1; s1 = s1_next)
+ {
+ s1_next = s1->next;
+ for (s2 = a->states_head; NULL != s2 && s1 != s2; s2 = s2_next)
+ {
+ s2_next = s2->next;
+ idx = s1->marked * state_cnt + s2->marked;
+ if (0 == (table[idx / 32] & (1 << (idx % 32))))
+ automaton_merge_states (ctx, a, s1, s2);
+ }
+ }
+
+ GNUNET_free (table);
+ return GNUNET_OK;
+}
+
+
+/**
+ * Minimize the given DFA 'a' by removing all unreachable states, removing all
+ * dead states and merging all non distinguishable states
+ *
+ * @param ctx context
+ * @param a DFA automaton
+ * @return GNUNET_OK on success
+ */
+static int
+dfa_minimize (struct REGEX_ITERNAL_Context *ctx,
+ struct REGEX_ITERNAL_Automaton *a)
+{
+ if (NULL == a)
+ return GNUNET_SYSERR;
+
+ GNUNET_assert (DFA == a->type);
+
+ /* 1. remove unreachable states */
+ dfa_remove_unreachable_states (a);
+
+ /* 2. remove dead states */
+ dfa_remove_dead_states (a);
+
+ /* 3. Merge nondistinguishable states */
+ if (GNUNET_OK != dfa_merge_nondistinguishable_states (ctx, a))
+ return GNUNET_SYSERR;
+ return GNUNET_OK;
+}
+
+
+/**
+ * Context for adding strided transitions to a DFA.
+ */
+struct REGEX_ITERNAL_Strided_Context
+{
+ /**
+ * Length of the strides.
+ */
+ const unsigned int stride;
+
+ /**
+ * Strided transitions DLL. New strided transitions will be stored in this
DLL
+ * and afterwards added to the DFA.
+ */
+ struct REGEX_ITERNAL_Transition *transitions_head;
+
+ /**
+ * Strided transitions DLL.
+ */
+ struct REGEX_ITERNAL_Transition *transitions_tail;
+};
+
+
+/**
+ * Recursive helper function to add strides to a DFA.
+ *
+ * @param cls context, contains stride length and strided transitions DLL.
+ * @param depth current depth of the depth-first traversal of the graph.
+ * @param label current label, string that contains all labels on the path from
+ * 'start' to 's'.
+ * @param start start state for the depth-first traversal of the graph.
+ * @param s current state in the depth-first traversal
+ */
+void
+dfa_add_multi_strides_helper (void *cls, const unsigned int depth, char *label,
+ struct REGEX_ITERNAL_State *start,
+ struct REGEX_ITERNAL_State *s)
+{
+ struct REGEX_ITERNAL_Strided_Context *ctx = cls;
+ struct REGEX_ITERNAL_Transition *t;
+ char *new_label;
+
+ if (depth == ctx->stride)
+ {
+ t = GNUNET_malloc (sizeof (struct REGEX_ITERNAL_Transition));
+ t->label = GNUNET_strdup (label);
+ t->to_state = s;
+ t->from_state = start;
+ GNUNET_CONTAINER_DLL_insert (ctx->transitions_head, ctx->transitions_tail,
+ t);
+ }
+ else
+ {
+ for (t = s->transitions_head; NULL != t; t = t->next)
+ {
+ /* Do not consider self-loops, because it end's up in too many
+ * transitions */
+ if (t->to_state == t->from_state)
+ continue;
+
+ if (NULL != label)
+ {
+ GNUNET_asprintf (&new_label, "%s%s", label, t->label);
+ }
+ else
+ new_label = GNUNET_strdup (t->label);
+
+ dfa_add_multi_strides_helper (cls, (depth + 1), new_label, start,
+ t->to_state);
+ }
+ }
+ GNUNET_free_non_null (label);
+}
+
+
+/**
+ * Function called for each state in the DFA. Starts a traversal of depth set
in
+ * context starting from state 's'.
+ *
+ * @param cls context.
+ * @param count not used.
+ * @param s current state.
+ */
+void
+dfa_add_multi_strides (void *cls, const unsigned int count,
+ struct REGEX_ITERNAL_State *s)
+{
+ dfa_add_multi_strides_helper (cls, 0, NULL, s, s);
+}
+
+
+/**
+ * Adds multi-strided transitions to the given 'dfa'.
+ *
+ * @param regex_ctx regex context needed to add transitions to the automaton.
+ * @param dfa DFA to which the multi strided transitions should be added.
+ * @param stride_len length of the strides.
+ */
+void
+REGEX_ITERNAL_dfa_add_multi_strides (struct REGEX_ITERNAL_Context *regex_ctx,
+ struct REGEX_ITERNAL_Automaton *dfa,
+ const unsigned int stride_len)
+{
+ struct REGEX_ITERNAL_Strided_Context ctx = { stride_len, NULL, NULL };
+ struct REGEX_ITERNAL_Transition *t;
+ struct REGEX_ITERNAL_Transition *t_next;
+
+ if (1 > stride_len || GNUNET_YES == dfa->is_multistrided)
+ return;
+
+ /* Compute the new transitions of given stride_len */
+ REGEX_ITERNAL_automaton_traverse (dfa, dfa->start, NULL, NULL,
+ &dfa_add_multi_strides, &ctx);
+
+ /* Add all the new transitions to the automaton. */
+ for (t = ctx.transitions_head; NULL != t; t = t_next)
+ {
+ t_next = t->next;
+ state_add_transition (regex_ctx, t->from_state, t->label, t->to_state);
+ GNUNET_CONTAINER_DLL_remove (ctx.transitions_head, ctx.transitions_tail,
t);
+ GNUNET_free_non_null (t->label);
+ GNUNET_free (t);
+ }
+
+ /* Mark this automaton as multistrided */
+ dfa->is_multistrided = GNUNET_YES;
+}
+
+/**
+ * Recursive Helper function for DFA path compression. Does DFS on the DFA
graph
+ * and adds new transitions to the given transitions DLL and marks states that
+ * should be removed by setting state->contained to GNUNET_YES.
+ *
+ * @param dfa DFA for which the paths should be compressed.
+ * @param start starting state for linear path search.
+ * @param cur current state in the recursive DFS.
+ * @param label current label (string of traversed labels).
+ * @param max_len maximal path compression length.
+ * @param transitions_head transitions DLL.
+ * @param transitions_tail transitions DLL.
+ */
+void
+dfa_compress_paths_helper (struct REGEX_ITERNAL_Automaton *dfa,
+ struct REGEX_ITERNAL_State *start,
+ struct REGEX_ITERNAL_State *cur, char *label,
+ unsigned int max_len,
+ struct REGEX_ITERNAL_Transition **transitions_head,
+ struct REGEX_ITERNAL_Transition **transitions_tail)
+{
+ struct REGEX_ITERNAL_Transition *t;
+ char *new_label;
+
+
+ if (NULL != label &&
+ ((cur->incoming_transition_count > 1 || GNUNET_YES == cur->accepting ||
+ GNUNET_YES == cur->marked) || (start != dfa->start && max_len > 0 &&
+ max_len == strlen (label)) ||
+ (start == dfa->start && GNUNET_REGEX_INITIAL_BYTES == strlen (label))))
+ {
+ t = GNUNET_malloc (sizeof (struct REGEX_ITERNAL_Transition));
+ t->label = GNUNET_strdup (label);
+ t->to_state = cur;
+ t->from_state = start;
+ GNUNET_CONTAINER_DLL_insert (*transitions_head, *transitions_tail, t);
+
+ if (GNUNET_NO == cur->marked)
+ {
+ dfa_compress_paths_helper (dfa, cur, cur, NULL, max_len,
transitions_head,
+ transitions_tail);
+ }
+ return;
+ }
+ else if (cur != start)
+ cur->contained = GNUNET_YES;
+
+ if (GNUNET_YES == cur->marked && cur != start)
+ return;
+
+ cur->marked = GNUNET_YES;
+
+
+ for (t = cur->transitions_head; NULL != t; t = t->next)
+ {
+ if (NULL != label)
+ GNUNET_asprintf (&new_label, "%s%s", label, t->label);
+ else
+ new_label = GNUNET_strdup (t->label);
+
+ if (t->to_state != cur)
+ {
+ dfa_compress_paths_helper (dfa, start, t->to_state, new_label, max_len,
+ transitions_head, transitions_tail);
+ }
+ GNUNET_free (new_label);
+ }
+}
+
+
+/**
+ * Compress paths in the given 'dfa'. Linear paths like 0->1->2->3 will be
+ * compressed to 0->3 by combining transitions.
+ *
+ * @param regex_ctx context for adding new transitions.
+ * @param dfa DFA representation, will directly modify the given DFA.
+ * @param max_len maximal length of the compressed paths.
+ */
+static void
+dfa_compress_paths (struct REGEX_ITERNAL_Context *regex_ctx,
+ struct REGEX_ITERNAL_Automaton *dfa, unsigned int max_len)
+{
+ struct REGEX_ITERNAL_State *s;
+ struct REGEX_ITERNAL_State *s_next;
+ struct REGEX_ITERNAL_Transition *t;
+ struct REGEX_ITERNAL_Transition *t_next;
+ struct REGEX_ITERNAL_Transition *transitions_head = NULL;
+ struct REGEX_ITERNAL_Transition *transitions_tail = NULL;
+
+ if (NULL == dfa)
+ return;
+
+ /* Count the incoming transitions on each state. */
+ for (s = dfa->states_head; NULL != s; s = s->next)
+ {
+ for (t = s->transitions_head; NULL != t; t = t->next)
+ {
+ if (NULL != t->to_state)
+ t->to_state->incoming_transition_count++;
+ }
+ }
+
+ /* Unmark all states. */
+ for (s = dfa->states_head; NULL != s; s = s->next)
+ {
+ s->marked = GNUNET_NO;
+ s->contained = GNUNET_NO;
+ }
+
+ /* Add strides and mark states that can be deleted. */
+ dfa_compress_paths_helper (dfa, dfa->start, dfa->start, NULL, max_len,
+ &transitions_head, &transitions_tail);
+
+ /* Add all the new transitions to the automaton. */
+ for (t = transitions_head; NULL != t; t = t_next)
+ {
+ t_next = t->next;
+ state_add_transition (regex_ctx, t->from_state, t->label, t->to_state);
+ GNUNET_CONTAINER_DLL_remove (transitions_head, transitions_tail, t);
+ GNUNET_free_non_null (t->label);
+ GNUNET_free (t);
+ }
+
+ /* Remove marked states (including their incoming and outgoing transitions).
*/
+ for (s = dfa->states_head; NULL != s; s = s_next)
+ {
+ s_next = s->next;
+ if (GNUNET_YES == s->contained)
+ automaton_remove_state (dfa, s);
+ }
+}
+
+
+/**
+ * Creates a new NFA fragment. Needs to be cleared using
+ * automaton_fragment_clear.
+ *
+ * @param start starting state
+ * @param end end state
+ *
+ * @return new NFA fragment
+ */
+static struct REGEX_ITERNAL_Automaton *
+nfa_fragment_create (struct REGEX_ITERNAL_State *start,
+ struct REGEX_ITERNAL_State *end)
+{
+ struct REGEX_ITERNAL_Automaton *n;
+
+ n = GNUNET_malloc (sizeof (struct REGEX_ITERNAL_Automaton));
+
+ n->type = NFA;
+ n->start = NULL;
+ n->end = NULL;
+ n->state_count = 0;
+
+ if (NULL == start || NULL == end)
+ return n;
+
+ automaton_add_state (n, end);
+ automaton_add_state (n, start);
+
+ n->state_count = 2;
+
+ n->start = start;
+ n->end = end;
+
+ return n;
+}
+
+
+/**
+ * Adds a list of states to the given automaton 'n'.
+ *
+ * @param n automaton to which the states should be added
+ * @param states_head head of the DLL of states
+ * @param states_tail tail of the DLL of states
+ */
+static void
+nfa_add_states (struct REGEX_ITERNAL_Automaton *n,
+ struct REGEX_ITERNAL_State *states_head,
+ struct REGEX_ITERNAL_State *states_tail)
+{
+ struct REGEX_ITERNAL_State *s;
+
+ if (NULL == n || NULL == states_head)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Could not add states\n");
+ return;
+ }
+
+ if (NULL == n->states_head)
+ {
+ n->states_head = states_head;
+ n->states_tail = states_tail;
+ return;
+ }
+
+ if (NULL != states_head)
+ {
+ n->states_tail->next = states_head;
+ n->states_tail = states_tail;
+ }
+
+ for (s = states_head; NULL != s; s = s->next)
+ n->state_count++;
+}
+
+
+/**
+ * Creates a new NFA state. Needs to be freed using automaton_destroy_state.
+ *
+ * @param ctx context
+ * @param accepting is it an accepting state or not
+ *
+ * @return new NFA state
+ */
+static struct REGEX_ITERNAL_State *
+nfa_state_create (struct REGEX_ITERNAL_Context *ctx, int accepting)
+{
+ struct REGEX_ITERNAL_State *s;
+
+ s = GNUNET_malloc (sizeof (struct REGEX_ITERNAL_State));
+ s->id = ctx->state_id++;
+ s->accepting = accepting;
+ s->marked = GNUNET_NO;
+ s->contained = 0;
+ s->index = -1;
+ s->lowlink = -1;
+ s->scc_id = 0;
+ s->name = NULL;
+ GNUNET_asprintf (&s->name, "s%i", s->id);
+
+ return s;
+}
+
+
+/**
+ * Calculates the closure set for the given set of states.
+ *
+ * @param ret set to sorted nfa closure on 'label' (epsilon closure if 'label'
is NULL)
+ * @param nfa the NFA containing 's'
+ * @param states list of states on which to base the closure on
+ * @param label transitioning label for which to base the closure on,
+ * pass NULL for epsilon transition
+ */
+static void
+nfa_closure_set_create (struct REGEX_ITERNAL_StateSet *ret,
+ struct REGEX_ITERNAL_Automaton *nfa,
+ struct REGEX_ITERNAL_StateSet *states, const char
*label)
+{
+ struct REGEX_ITERNAL_State *s;
+ unsigned int i;
+ struct REGEX_ITERNAL_StateSet_MDLL cls_stack;
+ struct REGEX_ITERNAL_State *clsstate;
+ struct REGEX_ITERNAL_State *currentstate;
+ struct REGEX_ITERNAL_Transition *ctran;
+
+ memset (ret, 0, sizeof (struct REGEX_ITERNAL_StateSet));
+ if (NULL == states)
+ return;
+
+ for (i = 0; i < states->off; i++)
+ {
+ s = states->states[i];
+
+ /* Add start state to closure only for epsilon closure */
+ if (NULL == label)
+ state_set_append (ret, s);
+
+ /* initialize work stack */
+ cls_stack.head = NULL;
+ cls_stack.tail = NULL;
+ GNUNET_CONTAINER_MDLL_insert (ST, cls_stack.head, cls_stack.tail, s);
+ cls_stack.len = 1;
+
+ while (NULL != (currentstate = cls_stack.tail))
+ {
+ GNUNET_CONTAINER_MDLL_remove (ST, cls_stack.head, cls_stack.tail,
+ currentstate);
+ cls_stack.len--;
+ for (ctran = currentstate->transitions_head; NULL != ctran;
+ ctran = ctran->next)
+ {
+ if (NULL == (clsstate = ctran->to_state))
+ continue;
+ if (0 != clsstate->contained)
+ continue;
+ if (0 != nullstrcmp (label, ctran->label))
+ continue;
+ state_set_append (ret, clsstate);
+ GNUNET_CONTAINER_MDLL_insert_tail (ST, cls_stack.head, cls_stack.tail,
+ clsstate);
+ cls_stack.len++;
+ clsstate->contained = 1;
+ }
+ }
+ }
+ for (i = 0; i < ret->off; i++)
+ ret->states[i]->contained = 0;
+
+ if (ret->off > 1)
+ qsort (ret->states, ret->off, sizeof (struct REGEX_ITERNAL_State *),
+ &state_compare);
+}
+
+
+/**
+ * Pops two NFA fragments (a, b) from the stack and concatenates them (ab)
+ *
+ * @param ctx context
+ */
+static void
+nfa_add_concatenation (struct REGEX_ITERNAL_Context *ctx)
+{
+ struct REGEX_ITERNAL_Automaton *a;
+ struct REGEX_ITERNAL_Automaton *b;
+ struct REGEX_ITERNAL_Automaton *new_nfa;
+
+ b = ctx->stack_tail;
+ GNUNET_assert (NULL != b);
+ GNUNET_CONTAINER_DLL_remove (ctx->stack_head, ctx->stack_tail, b);
+ a = ctx->stack_tail;
+ GNUNET_assert (NULL != a);
+ GNUNET_CONTAINER_DLL_remove (ctx->stack_head, ctx->stack_tail, a);
+
+ state_add_transition (ctx, a->end, NULL, b->start);
+ a->end->accepting = 0;
+ b->end->accepting = 1;
+
+ new_nfa = nfa_fragment_create (NULL, NULL);
+ nfa_add_states (new_nfa, a->states_head, a->states_tail);
+ nfa_add_states (new_nfa, b->states_head, b->states_tail);
+ new_nfa->start = a->start;
+ new_nfa->end = b->end;
+ new_nfa->state_count += a->state_count + b->state_count;
+ automaton_fragment_clear (a);
+ automaton_fragment_clear (b);
+
+ GNUNET_CONTAINER_DLL_insert_tail (ctx->stack_head, ctx->stack_tail, new_nfa);
+}
+
+
+/**
+ * Pops a NFA fragment from the stack (a) and adds a new fragment (a*)
+ *
+ * @param ctx context
+ */
+static void
+nfa_add_star_op (struct REGEX_ITERNAL_Context *ctx)
+{
+ struct REGEX_ITERNAL_Automaton *a;
+ struct REGEX_ITERNAL_Automaton *new_nfa;
+ struct REGEX_ITERNAL_State *start;
+ struct REGEX_ITERNAL_State *end;
+
+ a = ctx->stack_tail;
+
+ if (NULL == a)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "nfa_add_star_op failed, because there was no element on the
stack");
+ return;
+ }
+
+ GNUNET_CONTAINER_DLL_remove (ctx->stack_head, ctx->stack_tail, a);
+
+ start = nfa_state_create (ctx, 0);
+ end = nfa_state_create (ctx, 1);
+
+ state_add_transition (ctx, start, NULL, a->start);
+ state_add_transition (ctx, start, NULL, end);
+ state_add_transition (ctx, a->end, NULL, a->start);
+ state_add_transition (ctx, a->end, NULL, end);
+
+ a->end->accepting = 0;
+ end->accepting = 1;
+
+ new_nfa = nfa_fragment_create (start, end);
+ nfa_add_states (new_nfa, a->states_head, a->states_tail);
+ automaton_fragment_clear (a);
+
+ GNUNET_CONTAINER_DLL_insert_tail (ctx->stack_head, ctx->stack_tail, new_nfa);
+}
+
+
+/**
+ * Pops an NFA fragment (a) from the stack and adds a new fragment (a+)
+ *
+ * @param ctx context
+ */
+static void
+nfa_add_plus_op (struct REGEX_ITERNAL_Context *ctx)
+{
+ struct REGEX_ITERNAL_Automaton *a;
+
+ a = ctx->stack_tail;
+
+ if (NULL == a)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "nfa_add_plus_op failed, because there was no element on the
stack");
+ return;
+ }
+
+ GNUNET_CONTAINER_DLL_remove (ctx->stack_head, ctx->stack_tail, a);
+
+ state_add_transition (ctx, a->end, NULL, a->start);
+
+ GNUNET_CONTAINER_DLL_insert_tail (ctx->stack_head, ctx->stack_tail, a);
+}
+
+
+/**
+ * Pops an NFA fragment (a) from the stack and adds a new fragment (a?)
+ *
+ * @param ctx context
+ */
+static void
+nfa_add_question_op (struct REGEX_ITERNAL_Context *ctx)
+{
+ struct REGEX_ITERNAL_Automaton *a;
+ struct REGEX_ITERNAL_Automaton *new_nfa;
+ struct REGEX_ITERNAL_State *start;
+ struct REGEX_ITERNAL_State *end;
+
+ a = ctx->stack_tail;
+
+ if (NULL == a)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "nfa_add_question_op failed, because there was no element on
the stack");
+ return;
+ }
+
+ GNUNET_CONTAINER_DLL_remove (ctx->stack_head, ctx->stack_tail, a);
+
+ start = nfa_state_create (ctx, 0);
+ end = nfa_state_create (ctx, 1);
+
+ state_add_transition (ctx, start, NULL, a->start);
+ state_add_transition (ctx, start, NULL, end);
+ state_add_transition (ctx, a->end, NULL, end);
+
+ a->end->accepting = 0;
+
+ new_nfa = nfa_fragment_create (start, end);
+ nfa_add_states (new_nfa, a->states_head, a->states_tail);
+ GNUNET_CONTAINER_DLL_insert_tail (ctx->stack_head, ctx->stack_tail, new_nfa);
+ automaton_fragment_clear (a);
+}
+
+
+/**
+ * Pops two NFA fragments (a, b) from the stack and adds a new NFA fragment
that
+ * alternates between a and b (a|b)
+ *
+ * @param ctx context
+ */
+static void
+nfa_add_alternation (struct REGEX_ITERNAL_Context *ctx)
+{
+ struct REGEX_ITERNAL_Automaton *a;
+ struct REGEX_ITERNAL_Automaton *b;
+ struct REGEX_ITERNAL_Automaton *new_nfa;
+ struct REGEX_ITERNAL_State *start;
+ struct REGEX_ITERNAL_State *end;
+
+ b = ctx->stack_tail;
+ GNUNET_assert (NULL != b);
+ GNUNET_CONTAINER_DLL_remove (ctx->stack_head, ctx->stack_tail, b);
+ a = ctx->stack_tail;
+ GNUNET_assert (NULL != a);
+ GNUNET_CONTAINER_DLL_remove (ctx->stack_head, ctx->stack_tail, a);
+
+ start = nfa_state_create (ctx, 0);
+ end = nfa_state_create (ctx, 1);
+ state_add_transition (ctx, start, NULL, a->start);
+ state_add_transition (ctx, start, NULL, b->start);
+
+ state_add_transition (ctx, a->end, NULL, end);
+ state_add_transition (ctx, b->end, NULL, end);
+
+ a->end->accepting = 0;
+ b->end->accepting = 0;
+ end->accepting = 1;
+
+ new_nfa = nfa_fragment_create (start, end);
+ nfa_add_states (new_nfa, a->states_head, a->states_tail);
+ nfa_add_states (new_nfa, b->states_head, b->states_tail);
+ automaton_fragment_clear (a);
+ automaton_fragment_clear (b);
+
+ GNUNET_CONTAINER_DLL_insert_tail (ctx->stack_head, ctx->stack_tail, new_nfa);
+}
+
+
+/**
+ * Adds a new nfa fragment to the stack
+ *
+ * @param ctx context
+ * @param label label for nfa transition
+ */
+static void
+nfa_add_label (struct REGEX_ITERNAL_Context *ctx, const char *label)
+{
+ struct REGEX_ITERNAL_Automaton *n;
+ struct REGEX_ITERNAL_State *start;
+ struct REGEX_ITERNAL_State *end;
+
+ GNUNET_assert (NULL != ctx);
+
+ start = nfa_state_create (ctx, 0);
+ end = nfa_state_create (ctx, 1);
+ state_add_transition (ctx, start, label, end);
+ n = nfa_fragment_create (start, end);
+ GNUNET_assert (NULL != n);
+ GNUNET_CONTAINER_DLL_insert_tail (ctx->stack_head, ctx->stack_tail, n);
+}
+
+
+/**
+ * Initialize a new context
+ *
+ * @param ctx context
+ */
+static void
+REGEX_ITERNAL_context_init (struct REGEX_ITERNAL_Context *ctx)
+{
+ if (NULL == ctx)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Context was NULL!");
+ return;
+ }
+ ctx->state_id = 0;
+ ctx->transition_id = 0;
+ ctx->stack_head = NULL;
+ ctx->stack_tail = NULL;
+}
+
+
+/**
+ * Construct an NFA by parsing the regex string of length 'len'.
+ *
+ * @param regex regular expression string
+ * @param len length of the string
+ *
+ * @return NFA, needs to be freed using REGEX_ITERNAL_destroy_automaton
+ */
+struct REGEX_ITERNAL_Automaton *
+REGEX_ITERNAL_construct_nfa (const char *regex, const size_t len)
+{
+ struct REGEX_ITERNAL_Context ctx;
+ struct REGEX_ITERNAL_Automaton *nfa;
+ const char *regexp;
+ char curlabel[2];
+ char *error_msg;
+ unsigned int count;
+ unsigned int altcount;
+ unsigned int atomcount;
+ unsigned int poff;
+ unsigned int psize;
+ struct
+ {
+ int altcount;
+ int atomcount;
+ } *p;
+
+ if (NULL == regex || 0 == strlen (regex) || 0 == len)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "Could not parse regex. Empty regex string provided.\n");
+
+ return NULL;
+ }
+ REGEX_ITERNAL_context_init (&ctx);
+
+ regexp = regex;
+ curlabel[1] = '\0';
+ p = NULL;
+ error_msg = NULL;
+ altcount = 0;
+ atomcount = 0;
+ poff = 0;
+ psize = 0;
+
+ for (count = 0; count < len && *regexp; count++, regexp++)
+ {
+ switch (*regexp)
+ {
+ case '(':
+ if (atomcount > 1)
+ {
+ --atomcount;
+ nfa_add_concatenation (&ctx);
+ }
+ if (poff == psize)
+ GNUNET_array_grow (p, psize, psize * 2 + 4);
+ p[poff].altcount = altcount;
+ p[poff].atomcount = atomcount;
+ poff++;
+ altcount = 0;
+ atomcount = 0;
+ break;
+ case '|':
+ if (0 == atomcount)
+ {
+ error_msg = "Cannot append '|' to nothing";
+ goto error;
+ }
+ while (--atomcount > 0)
+ nfa_add_concatenation (&ctx);
+ altcount++;
+ break;
+ case ')':
+ if (0 == poff)
+ {
+ error_msg = "Missing opening '('";
+ goto error;
+ }
+ if (0 == atomcount)
+ {
+ /* Ignore this: "()" */
+ poff--;
+ altcount = p[poff].altcount;
+ atomcount = p[poff].atomcount;
+ break;
+ }
+ while (--atomcount > 0)
+ nfa_add_concatenation (&ctx);
+ for (; altcount > 0; altcount--)
+ nfa_add_alternation (&ctx);
+ poff--;
+ altcount = p[poff].altcount;
+ atomcount = p[poff].atomcount;
+ atomcount++;
+ break;
+ case '*':
+ if (atomcount == 0)
+ {
+ error_msg = "Cannot append '*' to nothing";
+ goto error;
+ }
+ nfa_add_star_op (&ctx);
+ break;
+ case '+':
+ if (atomcount == 0)
+ {
+ error_msg = "Cannot append '+' to nothing";
+ goto error;
+ }
+ nfa_add_plus_op (&ctx);
+ break;
+ case '?':
+ if (atomcount == 0)
+ {
+ error_msg = "Cannot append '?' to nothing";
+ goto error;
+ }
+ nfa_add_question_op (&ctx);
+ break;
+ default:
+ if (atomcount > 1)
+ {
+ --atomcount;
+ nfa_add_concatenation (&ctx);
+ }
+ curlabel[0] = *regexp;
+ nfa_add_label (&ctx, curlabel);
+ atomcount++;
+ break;
+ }
+ }
+ if (0 != poff)
+ {
+ error_msg = "Unbalanced parenthesis";
+ goto error;
+ }
+ while (--atomcount > 0)
+ nfa_add_concatenation (&ctx);
+ for (; altcount > 0; altcount--)
+ nfa_add_alternation (&ctx);
+
+ GNUNET_array_grow (p, psize, 0);
+
+ nfa = ctx.stack_tail;
+ GNUNET_CONTAINER_DLL_remove (ctx.stack_head, ctx.stack_tail, nfa);
+
+ if (NULL != ctx.stack_head)
+ {
+ error_msg = "Creating the NFA failed. NFA stack was not empty!";
+ goto error;
+ }
+
+ /* Remember the regex that was used to generate this NFA */
+ nfa->regex = GNUNET_strdup (regex);
+
+ /* create depth-first numbering of the states for pretty printing */
+ REGEX_ITERNAL_automaton_traverse (nfa, NULL, NULL, NULL, &number_states,
NULL);
+
+ /* No multistriding added so far */
+ nfa->is_multistrided = GNUNET_NO;
+
+ return nfa;
+
+error:
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Could not parse regex: `%s'\n", regex);
+ if (NULL != error_msg)
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "%s\n", error_msg);
+
+ GNUNET_free_non_null (p);
+
+ while (NULL != (nfa = ctx.stack_head))
+ {
+ GNUNET_CONTAINER_DLL_remove (ctx.stack_head, ctx.stack_tail, nfa);
+ REGEX_ITERNAL_automaton_destroy (nfa);
+ }
+
+ return NULL;
+}
+
+
+/**
+ * Create DFA states based on given 'nfa' and starting with 'dfa_state'.
+ *
+ * @param ctx context.
+ * @param nfa NFA automaton.
+ * @param dfa DFA automaton.
+ * @param dfa_state current dfa state, pass epsilon closure of first nfa state
+ * for starting.
+ */
+static void
+construct_dfa_states (struct REGEX_ITERNAL_Context *ctx,
+ struct REGEX_ITERNAL_Automaton *nfa,
+ struct REGEX_ITERNAL_Automaton *dfa,
+ struct REGEX_ITERNAL_State *dfa_state)
+{
+ struct REGEX_ITERNAL_Transition *ctran;
+ struct REGEX_ITERNAL_State *new_dfa_state;
+ struct REGEX_ITERNAL_State *state_contains;
+ struct REGEX_ITERNAL_State *state_iter;
+ struct REGEX_ITERNAL_StateSet tmp;
+ struct REGEX_ITERNAL_StateSet nfa_set;
+
+ for (ctran = dfa_state->transitions_head; NULL != ctran; ctran = ctran->next)
+ {
+ if (NULL == ctran->label || NULL != ctran->to_state)
+ continue;
+
+ nfa_closure_set_create (&tmp, nfa, &dfa_state->nfa_set, ctran->label);
+ nfa_closure_set_create (&nfa_set, nfa, &tmp, NULL);
+ state_set_clear (&tmp);
+
+ state_contains = NULL;
+ for (state_iter = dfa->states_head; NULL != state_iter;
+ state_iter = state_iter->next)
+ {
+ if (0 == state_set_compare (&state_iter->nfa_set, &nfa_set))
+ {
+ state_contains = state_iter;
+ break;
+ }
+ }
+ if (NULL == state_contains)
+ {
+ new_dfa_state = dfa_state_create (ctx, &nfa_set);
+ automaton_add_state (dfa, new_dfa_state);
+ ctran->to_state = new_dfa_state;
+ construct_dfa_states (ctx, nfa, dfa, new_dfa_state);
+ }
+ else
+ {
+ ctran->to_state = state_contains;
+ state_set_clear (&nfa_set);
+ }
+ }
+}
+
+
+/**
+ * Construct DFA for the given 'regex' of length 'len'.
+ *
+ * Path compression means, that for example a DFA o -> a -> b -> c -> o will be
+ * compressed to o -> abc -> o. Note that this parameter influences the
+ * non-determinism of states of the resulting NFA in the DHT (number of
outgoing
+ * edges with the same label). For example for an application that stores IPv4
+ * addresses as bitstrings it could make sense to limit the path compression to
+ * 4 or 8.
+ *
+ * @param regex regular expression string.
+ * @param len length of the regular expression.
+ * @param max_path_len limit the path compression length to the
+ * given value. If set to 1, no path compression is applied. Set to 0
for
+ * maximal possible path compression (generally not desireable).
+ * @return DFA, needs to be freed using REGEX_ITERNAL_automaton_destroy.
+ */
+struct REGEX_ITERNAL_Automaton *
+REGEX_ITERNAL_construct_dfa (const char *regex, const size_t len,
+ unsigned int max_path_len)
+{
+ struct REGEX_ITERNAL_Context ctx;
+ struct REGEX_ITERNAL_Automaton *dfa;
+ struct REGEX_ITERNAL_Automaton *nfa;
+ struct REGEX_ITERNAL_StateSet nfa_start_eps_cls;
+ struct REGEX_ITERNAL_StateSet singleton_set;
+
+ REGEX_ITERNAL_context_init (&ctx);
+
+ /* Create NFA */
+ // fprintf (stderr, "N");
+ nfa = REGEX_ITERNAL_construct_nfa (regex, len);
+
+ if (NULL == nfa)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "Could not create DFA, because NFA creation failed\n");
+ return NULL;
+ }
+
+ dfa = GNUNET_malloc (sizeof (struct REGEX_ITERNAL_Automaton));
+ dfa->type = DFA;
+ dfa->regex = GNUNET_strdup (regex);
+
+ /* Create DFA start state from epsilon closure */
+ memset (&singleton_set, 0, sizeof (struct REGEX_ITERNAL_StateSet));
+ state_set_append (&singleton_set, nfa->start);
+ nfa_closure_set_create (&nfa_start_eps_cls, nfa, &singleton_set, NULL);
+ state_set_clear (&singleton_set);
+ dfa->start = dfa_state_create (&ctx, &nfa_start_eps_cls);
+ automaton_add_state (dfa, dfa->start);
+
+ // fprintf (stderr, "D");
+ construct_dfa_states (&ctx, nfa, dfa, dfa->start);
+ REGEX_ITERNAL_automaton_destroy (nfa);
+
+ /* Minimize DFA */
+ // fprintf (stderr, "M");
+ if (GNUNET_OK != dfa_minimize (&ctx, dfa))
+ {
+ REGEX_ITERNAL_automaton_destroy (dfa);
+ return NULL;
+ }
+
+ /* Create proofs and hashes for all states */
+ if (GNUNET_OK != automaton_create_proofs (dfa))
+ {
+ REGEX_ITERNAL_automaton_destroy (dfa);
+ return NULL;
+ }
+
+ /* Compress linear DFA paths */
+ if (1 != max_path_len)
+ dfa_compress_paths (&ctx, dfa, max_path_len);
+
+ return dfa;
+}
+
+
+/**
+ * Free the memory allocated by constructing the REGEX_ITERNAL_Automaton data
+ * structure.
+ *
+ * @param a automaton to be destroyed
+ */
+void
+REGEX_ITERNAL_automaton_destroy (struct REGEX_ITERNAL_Automaton *a)
+{
+ struct REGEX_ITERNAL_State *s;
+ struct REGEX_ITERNAL_State *next_state;
+
+ if (NULL == a)
+ return;
+
+ GNUNET_free_non_null (a->regex);
+ GNUNET_free_non_null (a->canonical_regex);
+
+ for (s = a->states_head; NULL != s; s = next_state)
+ {
+ next_state = s->next;
+ GNUNET_CONTAINER_DLL_remove (a->states_head, a->states_tail, s);
+ automaton_destroy_state (s);
+ }
+
+ GNUNET_free (a);
+}
+
+
+/**
+ * Evaluates the given string using the given DFA automaton
+ *
+ * @param a automaton, type must be DFA
+ * @param string string that should be evaluated
+ *
+ * @return 0 if string matches, non 0 otherwise
+ */
+static int
+evaluate_dfa (struct REGEX_ITERNAL_Automaton *a, const char *string)
+{
+ const char *strp;
+ struct REGEX_ITERNAL_State *s;
+ unsigned int step_len;
+
+ if (DFA != a->type)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "Tried to evaluate DFA, but NFA automaton given");
+ return -1;
+ }
+
+ s = a->start;
+
+ /* If the string is empty but the starting state is accepting, we accept. */
+ if ((NULL == string || 0 == strlen (string)) && s->accepting)
+ return 0;
+
+ for (strp = string; NULL != strp && *strp; strp += step_len)
+ {
+ step_len = dfa_move (&s, strp);
+
+ if (NULL == s)
+ break;
+ }
+
+ if (NULL != s && s->accepting)
+ return 0;
+
+ return 1;
+}
+
+
+/**
+ * Evaluates the given string using the given NFA automaton
+ *
+ * @param a automaton, type must be NFA
+ * @param string string that should be evaluated
+ *
+ * @return 0 if string matches, non 0 otherwise
+ */
+static int
+evaluate_nfa (struct REGEX_ITERNAL_Automaton *a, const char *string)
+{
+ const char *strp;
+ char str[2];
+ struct REGEX_ITERNAL_State *s;
+ struct REGEX_ITERNAL_StateSet sset;
+ struct REGEX_ITERNAL_StateSet new_sset;
+ struct REGEX_ITERNAL_StateSet singleton_set;
+ unsigned int i;
+ int result;
+
+ if (NFA != a->type)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "Tried to evaluate NFA, but DFA automaton given");
+ return -1;
+ }
+
+ /* If the string is empty but the starting state is accepting, we accept. */
+ if ((NULL == string || 0 == strlen (string)) && a->start->accepting)
+ return 0;
+
+ result = 1;
+ memset (&singleton_set, 0, sizeof (struct REGEX_ITERNAL_StateSet));
+ state_set_append (&singleton_set, a->start);
+ nfa_closure_set_create (&sset, a, &singleton_set, NULL);
+ state_set_clear (&singleton_set);
+
+ str[1] = '\0';
+ for (strp = string; NULL != strp && *strp; strp++)
+ {
+ str[0] = *strp;
+ nfa_closure_set_create (&new_sset, a, &sset, str);
+ state_set_clear (&sset);
+ nfa_closure_set_create (&sset, a, &new_sset, 0);
+ state_set_clear (&new_sset);
+ }
+
+ for (i = 0; i < sset.off; i++)
+ {
+ s = sset.states[i];
+ if ( (NULL != s) && (s->accepting) )
+ {
+ result = 0;
+ break;
+ }
+ }
+
+ state_set_clear (&sset);
+ return result;
+}
+
+
+/**
+ * Evaluates the given 'string' against the given compiled regex
+ *
+ * @param a automaton
+ * @param string string to check
+ *
+ * @return 0 if string matches, non 0 otherwise
+ */
+int
+REGEX_ITERNAL_eval (struct REGEX_ITERNAL_Automaton *a, const char *string)
+{
+ int result;
+
+ switch (a->type)
+ {
+ case DFA:
+ result = evaluate_dfa (a, string);
+ break;
+ case NFA:
+ result = evaluate_nfa (a, string);
+ break;
+ default:
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "Evaluating regex failed, automaton has no type!\n");
+ result = GNUNET_SYSERR;
+ break;
+ }
+
+ return result;
+}
+
+
+/**
+ * Get the canonical regex of the given automaton.
+ * When constructing the automaton a proof is computed for each state,
+ * consisting of the regular expression leading to this state. A complete
+ * regex for the automaton can be computed by combining these proofs.
+ * As of now this function is only useful for testing.
+ *
+ * @param a automaton for which the canonical regex should be returned.
+ *
+ * @return
+ */
+const char *
+REGEX_ITERNAL_get_canonical_regex (struct REGEX_ITERNAL_Automaton *a)
+{
+ if (NULL == a)
+ return NULL;
+
+ return a->canonical_regex;
+}
+
+
+/**
+ * Get the number of transitions that are contained in the given automaton.
+ *
+ * @param a automaton for which the number of transitions should be returned.
+ *
+ * @return number of transitions in the given automaton.
+ */
+unsigned int
+REGEX_ITERNAL_get_transition_count (struct REGEX_ITERNAL_Automaton *a)
+{
+ unsigned int t_count;
+ struct REGEX_ITERNAL_State *s;
+
+ if (NULL == a)
+ return 0;
+
+ t_count = 0;
+ for (s = a->states_head; NULL != s; s = s->next)
+ t_count += s->transition_count;
+
+ return t_count;
+}
+
+
+/**
+ * Get the first key for the given 'input_string'. This hashes the first x bits
+ * of the 'input_string'.
+ *
+ * @param input_string string.
+ * @param string_len length of the 'input_string'.
+ * @param key pointer to where to write the hash code.
+ *
+ * @return number of bits of 'input_string' that have been consumed
+ * to construct the key
+ */
+size_t
+REGEX_ITERNAL_get_first_key (const char *input_string, size_t string_len,
+ struct GNUNET_HashCode * key)
+{
+ unsigned int size;
+
+ size =
+ string_len <
+ GNUNET_REGEX_INITIAL_BYTES ? string_len : GNUNET_REGEX_INITIAL_BYTES;
+
+ if (NULL == input_string)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Given input string was NULL!\n");
+ return 0;
+ }
+
+ GNUNET_CRYPTO_hash (input_string, size, key);
+
+ return size;
+}
+
+
+/**
+ * Check if the given 'proof' matches the given 'key'.
+ *
+ * @param proof partial regex of a state.
+ * @param key hash of a state.
+ *
+ * @return GNUNET_OK if the proof is valid for the given key.
+ */
+int
+REGEX_ITERNAL_check_proof (const char *proof, const struct GNUNET_HashCode
*key)
+{
+ struct GNUNET_HashCode key_check;
+
+ if (NULL == proof || NULL == key)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Proof check failed, was NULL.\n");
+ return GNUNET_NO;
+ }
+
+ GNUNET_CRYPTO_hash (proof, strlen (proof), &key_check);
+ return (0 ==
+ GNUNET_CRYPTO_hash_cmp (key, &key_check)) ? GNUNET_OK : GNUNET_NO;
+}
+
+
+/**
+ * Recursive function that calls the iterator for each synthetic start state.
+ *
+ * @param min_len minimum length of the path in the graph.
+ * @param max_len maximum length of the path in the graph.
+ * @param consumed_string string consumed by traversing the graph till this
state.
+ * @param state current state of the automaton.
+ * @param iterator iterator function called for each edge.
+ * @param iterator_cls closure for the iterator function.
+ */
+static void
+iterate_initial_edge (const unsigned int min_len, const unsigned int max_len,
+ char *consumed_string, struct REGEX_ITERNAL_State *state,
+ REGEX_ITERNAL_KeyIterator iterator, void *iterator_cls)
+{
+ unsigned int i;
+ char *temp;
+ struct REGEX_ITERNAL_Transition *t;
+ unsigned int num_edges = state->transition_count;
+ struct REGEX_ITERNAL_Edge edges[num_edges];
+ struct REGEX_ITERNAL_Edge edge[1];
+ struct GNUNET_HashCode hash;
+ struct GNUNET_HashCode hash_new;
+
+ unsigned int cur_len;
+
+ if (NULL != consumed_string)
+ cur_len = strlen (consumed_string);
+ else
+ cur_len = 0;
+
+ if ((cur_len >= min_len || GNUNET_YES == state->accepting) && cur_len > 0 &&
+ NULL != consumed_string)
+ {
+ if (cur_len <= max_len)
+ {
+ if (state->proof != NULL && 0 != strcmp (consumed_string, state->proof))
+ {
+ for (i = 0, t = state->transitions_head; NULL != t && i < num_edges;
+ t = t->next, i++)
+ {
+ edges[i].label = t->label;
+ edges[i].destination = t->to_state->hash;
+ }
+ GNUNET_CRYPTO_hash (consumed_string, strlen (consumed_string), &hash);
+ iterator (iterator_cls, &hash, consumed_string, state->accepting,
+ num_edges, edges);
+ }
+
+ if (GNUNET_YES == state->accepting && cur_len > 1 &&
+ state->transition_count < 1 && cur_len < max_len)
+ {
+ /* Special case for regex consisting of just a string that is shorter
than
+ * max_len */
+ edge[0].label = &consumed_string[cur_len - 1];
+ edge[0].destination = state->hash;
+ temp = GNUNET_strdup (consumed_string);
+ temp[cur_len - 1] = '\0';
+ GNUNET_CRYPTO_hash (temp, cur_len - 1, &hash_new);
+ iterator (iterator_cls, &hash_new, temp, GNUNET_NO, 1, edge);
+ GNUNET_free (temp);
+ }
+ }
+ else if (max_len < cur_len)
+ {
+ /* Case where the concatenated labels are longer than max_len, then
split. */
+ edge[0].label = &consumed_string[max_len];
+ edge[0].destination = state->hash;
+ temp = GNUNET_strdup (consumed_string);
+ temp[max_len] = '\0';
+ GNUNET_CRYPTO_hash (temp, max_len, &hash);
+ iterator (iterator_cls, &hash, temp, GNUNET_NO, 1, edge);
+ GNUNET_free (temp);
+ }
+ }
+
+ if (cur_len < max_len)
+ {
+ for (t = state->transitions_head; NULL != t; t = t->next)
+ {
+ if (NULL != consumed_string)
+ GNUNET_asprintf (&temp, "%s%s", consumed_string, t->label);
+ else
+ GNUNET_asprintf (&temp, "%s", t->label);
+
+ iterate_initial_edge (min_len, max_len, temp, t->to_state, iterator,
+ iterator_cls);
+ GNUNET_free (temp);
+ }
+ }
+}
+
+
+/**
+ * Iterate over all edges starting from start state of automaton 'a'. Calling
+ * iterator for each edge.
+ *
+ * @param a automaton.
+ * @param iterator iterator called for each edge.
+ * @param iterator_cls closure.
+ */
+void
+REGEX_ITERNAL_iterate_all_edges (struct REGEX_ITERNAL_Automaton *a,
+ REGEX_ITERNAL_KeyIterator iterator,
+ void *iterator_cls)
+{
+ struct REGEX_ITERNAL_State *s;
+
+ for (s = a->states_head; NULL != s; s = s->next)
+ {
+ struct REGEX_ITERNAL_Edge edges[s->transition_count];
+ unsigned int num_edges;
+
+ num_edges = state_get_edges (s, edges);
+
+ if ((NULL != s->proof && 0 < strlen (s->proof)) || s->accepting)
+ iterator (iterator_cls, &s->hash, s->proof, s->accepting, num_edges,
+ edges);
+
+ s->marked = GNUNET_NO;
+ }
+
+ iterate_initial_edge (GNUNET_REGEX_INITIAL_BYTES, GNUNET_REGEX_INITIAL_BYTES,
+ NULL, a->start, iterator, iterator_cls);
+}
+
+
+
+
+/* end of regex.c */
Modified: gnunet/src/regex/regex_internal.h
===================================================================
--- gnunet/src/regex/regex_internal.h 2013-06-20 08:32:50 UTC (rev 27498)
+++ gnunet/src/regex/regex_internal.h 2013-06-20 08:55:56 UTC (rev 27499)
@@ -444,36 +444,7 @@
const unsigned int stride_len);
-/**
- * Generate a (pseudo) random regular expression of length 'rx_length', as well
- * as a (optional) string that will be matched by the generated regex. The
- * returned regex needs to be freed.
- *
- * @param rx_length length of the random regex.
- * @param matching_str (optional) pointer to a string that will contain a
string
- * that will be matched by the generated regex, if
- * 'matching_str' pointer was not NULL.
- *
- * @return NULL if 'rx_length' is 0, a random regex of length 'rx_length',
which
- * needs to be freed, otherwise.
- */
-char *
-REGEX_ITERNAL_generate_random_regex (size_t rx_length, char *matching_str);
-
-/**
- * Generate a random string of maximum length 'max_len' that only contains
literals allowed
- * in a regular expression. The string might be 0 chars long but is garantueed
- * to be shorter or equal to 'max_len'.
- *
- * @param max_len maximum length of the string that should be generated.
- *
- * @return random string that needs to be freed.
- */
-char *
-REGEX_ITERNAL_generate_random_string (size_t max_len);
-
-
#if 0 /* keep Emacsens' auto-indent happy */
{
#endif
Copied: gnunet/src/regex/regex_internal_dht.c (from rev 27498,
gnunet/src/regex/regex_dht.c)
===================================================================
--- gnunet/src/regex/regex_internal_dht.c (rev 0)
+++ gnunet/src/regex/regex_internal_dht.c 2013-06-20 08:55:56 UTC (rev
27499)
@@ -0,0 +1,812 @@
+/*
+ This file is part of GNUnet
+ (C) 2012 Christian Grothoff (and other contributing authors)
+
+ GNUnet is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published
+ by the Free Software Foundation; either version 3, or (at your
+ option) any later version.
+
+ GNUnet is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GNUnet; see the file COPYING. If not, write to the
+ Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA.
+*/
+/**
+ * @file src/regex/regex_internal_dht.c
+ * @brief library to announce regexes in the network and match strings
+ * against published regexes.
+ * @author Bartlomiej Polot
+ */
+#include "platform.h"
+#include "regex_internal_lib.h"
+#include "regex_block_lib.h"
+#include "gnunet_dht_service.h"
+#include "gnunet_statistics_service.h"
+
+#define LOG(kind,...) GNUNET_log_from (kind,"regex-dht",__VA_ARGS__)
+
+/* FIXME: OPTION (API, CONFIG) */
+#define DHT_REPLICATION 5
+#define DHT_TTL GNUNET_TIME_UNIT_HOURS
+#define DEBUG_DHT GNUNET_NO
+
+#if DEBUG_DHT
+#define DHT_OPT GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE |
GNUNET_DHT_RO_RECORD_ROUTE
+#else
+#define DHT_OPT GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE
+#endif
+
+struct REGEX_ITERNAL_Announcement
+{
+ /**
+ * DHT handle to use, must be initialized externally.
+ */
+ struct GNUNET_DHT_Handle *dht;
+
+ /**
+ * Regular expression.
+ */
+ const char *regex;
+
+ /**
+ * Automaton representation of the regex (expensive to build).
+ */
+ struct REGEX_ITERNAL_Automaton* dfa;
+
+ /**
+ * Identity under which to announce the regex.
+ */
+ struct GNUNET_PeerIdentity id;
+
+ /**
+ * Optional statistics handle to report usage. Can be NULL.
+ */
+ struct GNUNET_STATISTICS_Handle *stats;
+};
+
+
+/**
+ * Regex callback iterator to store own service description in the DHT.
+ *
+ * @param cls closure.
+ * @param key hash for current state.
+ * @param proof proof for current state.
+ * @param accepting GNUNET_YES if this is an accepting state, GNUNET_NO if not.
+ * @param num_edges number of edges leaving current state.
+ * @param edges edges leaving current state.
+ */
+static void
+regex_iterator (void *cls,
+ const struct GNUNET_HashCode *key,
+ const char *proof,
+ int accepting,
+ unsigned int num_edges,
+ const struct REGEX_ITERNAL_Edge *edges)
+{
+ struct REGEX_ITERNAL_Announcement *h = cls;
+ struct RegexBlock *block;
+ struct RegexEdge *block_edge;
+ size_t size;
+ size_t len;
+ unsigned int i;
+ unsigned int offset;
+ char *aux;
+
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ " regex dht put for state %s\n",
+ GNUNET_h2s (key));
+ LOG (GNUNET_ERROR_TYPE_DEBUG, " proof: %s\n", proof);
+ LOG (GNUNET_ERROR_TYPE_DEBUG, " num edges: %u\n", num_edges);
+
+ if (GNUNET_YES == accepting)
+ {
+ struct RegexAccept block;
+
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ " state %s is accepting, putting own id\n",
+ GNUNET_h2s(key));
+ size = sizeof (block);
+ block.key = *key;
+ block.id = h->id;
+ GNUNET_STATISTICS_update (h->stats, "# regex accepting blocks stored",
+ 1, GNUNET_NO);
+ GNUNET_STATISTICS_update (h->stats, "# regex accepting block bytes stored",
+ sizeof (block), GNUNET_NO);
+ (void)
+ GNUNET_DHT_put (h->dht, key,
+ DHT_REPLICATION,
+ DHT_OPT | GNUNET_DHT_RO_RECORD_ROUTE,
+ GNUNET_BLOCK_TYPE_REGEX_ACCEPT,
+ size,
+ (char *) &block,
+ GNUNET_TIME_relative_to_absolute (DHT_TTL),
+ DHT_TTL,
+ NULL, NULL);
+ }
+ len = strlen(proof);
+ size = sizeof (struct RegexBlock) + len;
+ block = GNUNET_malloc (size);
+
+ block->key = *key;
+ block->n_proof = htonl (len);
+ block->n_edges = htonl (num_edges);
+ block->accepting = htonl (accepting);
+
+ /* Store the proof at the end of the block. */
+ aux = (char *) &block[1];
+ memcpy (aux, proof, len);
+ aux = &aux[len];
+
+ /* Store each edge in a variable length MeshEdge struct at the
+ * very end of the MeshRegexBlock structure.
+ */
+ for (i = 0; i < num_edges; i++)
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG, " edge %s towards %s\n",
+ edges[i].label, GNUNET_h2s(&edges[i].destination));
+
+ /* aux points at the end of the last block */
+ len = strlen (edges[i].label);
+ size += sizeof (struct RegexEdge) + len;
+ // Calculate offset FIXME is this ok? use size instead?
+ offset = aux - (char *) block;
+ block = GNUNET_realloc (block, size);
+ aux = &((char *) block)[offset];
+ block_edge = (struct RegexEdge *) aux;
+ block_edge->key = edges[i].destination;
+ block_edge->n_token = htonl (len);
+ aux = (char *) &block_edge[1];
+ memcpy (aux, edges[i].label, len);
+ aux = &aux[len];
+ }
+ (void)
+ GNUNET_DHT_put (h->dht, key,
+ DHT_REPLICATION,
+ DHT_OPT,
+ GNUNET_BLOCK_TYPE_REGEX, size,
+ (char *) block,
+ GNUNET_TIME_relative_to_absolute (DHT_TTL),
+ DHT_TTL,
+ NULL, NULL);
+ GNUNET_STATISTICS_update (h->stats, "# regex blocks stored",
+ 1, GNUNET_NO);
+ GNUNET_STATISTICS_update (h->stats, "# regex block bytes stored",
+ size, GNUNET_NO);
+ GNUNET_free (block);
+}
+
+
+struct REGEX_ITERNAL_Announcement *
+REGEX_ITERNAL_announce (struct GNUNET_DHT_Handle *dht,
+ const struct GNUNET_PeerIdentity *id,
+ const char *regex,
+ uint16_t compression,
+ struct GNUNET_STATISTICS_Handle *stats)
+{
+ struct REGEX_ITERNAL_Announcement *h;
+
+ GNUNET_assert (NULL != dht);
+ h = GNUNET_malloc (sizeof (struct REGEX_ITERNAL_Announcement));
+ h->regex = regex;
+ h->dht = dht;
+ h->stats = stats;
+ h->id = *id;
+ h->dfa = REGEX_ITERNAL_construct_dfa (regex,
+ strlen (regex),
+ compression);
+ REGEX_ITERNAL_reannounce (h);
+ return h;
+}
+
+
+void
+REGEX_ITERNAL_reannounce (struct REGEX_ITERNAL_Announcement *h)
+{
+ GNUNET_assert (NULL != h->dfa); /* make sure to call announce first */
+ LOG (GNUNET_ERROR_TYPE_INFO, "REGEX_ITERNAL_reannounce: %.60s\n", h->regex);
+ LOG (GNUNET_ERROR_TYPE_DEBUG, " full: %s\n", h->regex);
+ REGEX_ITERNAL_iterate_all_edges (h->dfa, ®ex_iterator, h);
+}
+
+
+void
+REGEX_ITERNAL_announce_cancel (struct REGEX_ITERNAL_Announcement *h)
+{
+ REGEX_ITERNAL_automaton_destroy (h->dfa);
+ GNUNET_free (h);
+}
+
+
+/******************************************************************************/
+
+
+/**
+ * Struct to keep state of running searches that have consumed a part of
+ * the inital string.
+ */
+struct RegexSearchContext
+{
+ /**
+ * Part of the description already consumed by
+ * this particular search branch.
+ */
+ size_t position;
+
+ /**
+ * Information about the search.
+ */
+ struct REGEX_ITERNAL_Search *info;
+
+ /**
+ * We just want to look for one edge, the longer the better.
+ * Keep its length.
+ */
+ unsigned int longest_match;
+
+ /**
+ * Destination hash of the longest match.
+ */
+ struct GNUNET_HashCode hash;
+};
+
+
+/**
+ * Struct to keep information of searches of services described by a regex
+ * using a user-provided string service description.
+ */
+struct REGEX_ITERNAL_Search
+{
+ /**
+ * DHT handle to use, must be initialized externally.
+ */
+ struct GNUNET_DHT_Handle *dht;
+
+ /**
+ * Optional statistics handle to report usage. Can be NULL.
+ */
+ struct GNUNET_STATISTICS_Handle *stats;
+
+ /**
+ * User provided description of the searched service.
+ */
+ char *description;
+
+ /**
+ * Running DHT GETs.
+ */
+ struct GNUNET_CONTAINER_MultiHashMap *dht_get_handles;
+
+ /**
+ * Results from running DHT GETs.
+ */
+ struct GNUNET_CONTAINER_MultiHashMap *dht_get_results;
+
+ /**
+ * Contexts, for each running DHT GET. Free all on end of search.
+ */
+ struct RegexSearchContext **contexts;
+
+ /**
+ * Number of contexts (branches/steps in search).
+ */
+ unsigned int n_contexts;
+
+ /**
+ * @param callback Callback for found peers.
+ */
+ REGEX_ITERNAL_Found callback;
+
+ /**
+ * @param callback_cls Closure for @c callback.
+ */
+ void *callback_cls;
+};
+
+
+
+/**
+ * Jump to the next edge, with the longest matching token.
+ *
+ * @param block Block found in the DHT.
+ * @param size Size of the block.
+ * @param ctx Context of the search.
+ *
+ * @return GNUNET_YES if should keep iterating, GNUNET_NO otherwise.
+ */
+static void
+regex_next_edge (const struct RegexBlock *block,
+ size_t size,
+ struct RegexSearchContext *ctx);
+
+
+/**
+ * Function to process DHT string to regex matching.
+ * Called on each result obtained for the DHT search.
+ *
+ * @param cls Closure (search context).
+ * @param exp When will this value expire.
+ * @param key Key of the result.
+ * @param get_path Path of the get request.
+ * @param get_path_length Lenght of get_path.
+ * @param put_path Path of the put request.
+ * @param put_path_length Length of the put_path.
+ * @param type Type of the result.
+ * @param size Number of bytes in data.
+ * @param data Pointer to the result data.
+ */
+static void
+dht_get_string_accept_handler (void *cls, struct GNUNET_TIME_Absolute exp,
+ const struct GNUNET_HashCode * key,
+ const struct GNUNET_PeerIdentity *get_path,
+ unsigned int get_path_length,
+ const struct GNUNET_PeerIdentity *put_path,
+ unsigned int put_path_length,
+ enum GNUNET_BLOCK_Type type,
+ size_t size, const void *data)
+{
+ const struct RegexAccept *block = data;
+ struct RegexSearchContext *ctx = cls;
+ struct REGEX_ITERNAL_Search *info = ctx->info;
+
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "Got regex results from DHT!\n");
+ LOG (GNUNET_ERROR_TYPE_INFO, " accept for %s (key %s)\n",
+ info->description, GNUNET_h2s(key));
+
+ GNUNET_STATISTICS_update (info->stats, "# regex accepting blocks found",
+ 1, GNUNET_NO);
+ GNUNET_STATISTICS_update (info->stats, "# regex accepting block bytes found",
+ size, GNUNET_NO);
+
+ info->callback (info->callback_cls,
+ &block->id,
+ get_path, get_path_length,
+ put_path, put_path_length);
+}
+
+
+/**
+ * Find a path to a peer that offers a regex servcie compatible
+ * with a given string.
+ *
+ * @param key The key of the accepting state.
+ * @param ctx Context containing info about the string, tunnel, etc.
+ */
+static void
+regex_find_path (const struct GNUNET_HashCode *key,
+ struct RegexSearchContext *ctx)
+{
+ struct GNUNET_DHT_GetHandle *get_h;
+
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "Found peer by service\n");
+ LOG (GNUNET_ERROR_TYPE_INFO, " find accept for %s\n", GNUNET_h2s (key));
+ get_h = GNUNET_DHT_get_start (ctx->info->dht, /* handle */
+ GNUNET_BLOCK_TYPE_REGEX_ACCEPT, /* type */
+ key, /* key to search */
+ DHT_REPLICATION, /* replication level */
+ DHT_OPT | GNUNET_DHT_RO_RECORD_ROUTE,
+ NULL, /* xquery */ // FIXME BLOOMFILTER
+ 0, /* xquery bits */ // FIXME BLOOMFILTER
SIZE
+ &dht_get_string_accept_handler, ctx);
+ GNUNET_break (GNUNET_OK ==
+ GNUNET_CONTAINER_multihashmap_put(ctx->info->dht_get_handles,
+ key,
+ get_h,
+
GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE));
+}
+
+
+/**
+ * Function to process DHT string to regex matching.
+ * Called on each result obtained for the DHT search.
+ *
+ * @param cls closure (search context)
+ * @param exp when will this value expire
+ * @param key key of the result
+ * @param get_path path of the get request (not used)
+ * @param get_path_length lenght of get_path (not used)
+ * @param put_path path of the put request (not used)
+ * @param put_path_length length of the put_path (not used)
+ * @param type type of the result
+ * @param size number of bytes in data
+ * @param data pointer to the result data
+ *
+ * TODO: re-issue the request after certain time? cancel after X results?
+ */
+static void
+dht_get_string_handler (void *cls, struct GNUNET_TIME_Absolute exp,
+ const struct GNUNET_HashCode * key,
+ const struct GNUNET_PeerIdentity *get_path,
+ unsigned int get_path_length,
+ const struct GNUNET_PeerIdentity *put_path,
+ unsigned int put_path_length,
+ enum GNUNET_BLOCK_Type type,
+ size_t size, const void *data)
+{
+ const struct RegexBlock *block = data;
+ struct RegexSearchContext *ctx = cls;
+ struct REGEX_ITERNAL_Search *info = ctx->info;
+ void *copy;
+ size_t len;
+ char *datastore;
+
+#if DEBUG_DHT
+ if (NULL != put_path && 0 != put_path_length)
+ {
+ datastore = GNUNET_strdup (GNUNET_i2s (&put_path[put_path_length - 1]));
+ }
+ else
+ {
+ GNUNET_asprintf (&datastore, "?? %u/%u", put_path_length, get_path_length);
+ }
+#else
+ datastore = GNUNET_strdup ("N/A");
+#endif
+
+ LOG (GNUNET_ERROR_TYPE_INFO, " DHT GET result for %s (%s) at %s\n",
+ GNUNET_h2s (key), ctx->info->description, datastore);
+ GNUNET_free (datastore);
+
+ copy = GNUNET_malloc (size);
+ memcpy (copy, data, size);
+ GNUNET_break (
+ GNUNET_OK ==
+ GNUNET_CONTAINER_multihashmap_put (info->dht_get_results,
+ &((struct RegexBlock *)copy)->key, copy,
+
GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE)
+ );
+ len = ntohl (block->n_proof);
+ {
+ char proof[len + 1];
+
+ memcpy (proof, &block[1], len);
+ proof[len] = '\0';
+ if (GNUNET_OK != REGEX_ITERNAL_check_proof (proof, key))
+ {
+ GNUNET_break_op (0);
+ return;
+ }
+ }
+ len = strlen (info->description);
+ if (len == ctx->position) // String processed
+ {
+ if (GNUNET_YES == ntohl (block->accepting))
+ {
+ regex_find_path (key, ctx);
+ }
+ else
+ {
+ LOG (GNUNET_ERROR_TYPE_INFO, " block not accepting!\n");
+ // FIXME REGEX this block not successful, wait for more? start timeout?
+ }
+ return;
+ }
+ regex_next_edge (block, size, ctx);
+}
+
+
+/**
+ * Iterator over found existing mesh regex blocks that match an ongoing search.
+ *
+ * @param cls Closure (current context)-
+ * @param key Current key code (key for cached block).
+ * @param value Value in the hash map (cached RegexBlock).
+ * @return GNUNET_YES: we should always continue to iterate.
+ */
+static int
+regex_result_iterator (void *cls,
+ const struct GNUNET_HashCode * key,
+ void *value)
+{
+ struct RegexBlock *block = value;
+ struct RegexSearchContext *ctx = cls;
+
+ if (GNUNET_YES == ntohl(block->accepting) &&
+ ctx->position == strlen (ctx->info->description))
+ {
+ LOG (GNUNET_ERROR_TYPE_INFO, " * Found accepting known block\n");
+ regex_find_path (key, ctx);
+ return GNUNET_YES; // We found an accept state!
+ }
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "* %u, %u, [%u]\n",
+ ctx->position, strlen(ctx->info->description),
+ ntohl(block->accepting));
+
+ regex_next_edge (block, SIZE_MAX, ctx);
+
+ GNUNET_STATISTICS_update (ctx->info->stats, "# regex mesh blocks iterated",
+ 1, GNUNET_NO);
+
+ return GNUNET_YES;
+}
+
+
+/**
+ * Iterator over edges in a regex block retrieved from the DHT.
+ *
+ * @param cls Closure (context of the search).
+ * @param token Token that follows to next state.
+ * @param len Lenght of token.
+ * @param key Hash of next state.
+ *
+ * @return GNUNET_YES if should keep iterating, GNUNET_NO otherwise.
+ */
+static int
+regex_edge_iterator (void *cls,
+ const char *token,
+ size_t len,
+ const struct GNUNET_HashCode *key)
+{
+ struct RegexSearchContext *ctx = cls;
+ struct REGEX_ITERNAL_Search *info = ctx->info;
+ const char *current;
+ size_t current_len;
+
+ GNUNET_STATISTICS_update (info->stats, "# regex edges iterated",
+ 1, GNUNET_NO);
+
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "* Start of regex edge iterator\n");
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "* descr : %s\n", info->description);
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "* posit : %u\n", ctx->position);
+ current = &info->description[ctx->position];
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "* currt : %s\n", current);
+ current_len = strlen (info->description) - ctx->position;
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "* ctlen : %u\n", current_len);
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "* tklen : %u\n", len);
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "* token : %.*s\n", len, token);
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "* nextk : %s\n", GNUNET_h2s(key));
+ if (len > current_len)
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "* Token too long, END\n");
+ return GNUNET_YES; // Token too long, wont match
+ }
+ if (0 != strncmp (current, token, len))
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "* Token doesn't match, END\n");
+ return GNUNET_YES; // Token doesn't match
+ }
+
+ if (len > ctx->longest_match)
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "* Token is longer, KEEP\n");
+ ctx->longest_match = len;
+ ctx->hash = *key;
+ }
+ else
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "* Token is not longer, IGNORE\n");
+ }
+
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "* End of regex edge iterator\n");
+ return GNUNET_YES;
+}
+
+
+/**
+ * Jump to the next edge, with the longest matching token.
+ *
+ * @param block Block found in the DHT.
+ * @param size Size of the block.
+ * @param ctx Context of the search.
+ *
+ * @return GNUNET_YES if should keep iterating, GNUNET_NO otherwise.
+ */
+static void
+regex_next_edge (const struct RegexBlock *block,
+ size_t size,
+ struct RegexSearchContext *ctx)
+{
+ struct RegexSearchContext *new_ctx;
+ struct REGEX_ITERNAL_Search *info = ctx->info;
+ struct GNUNET_DHT_GetHandle *get_h;
+ struct GNUNET_HashCode *hash;
+ const char *rest;
+ int result;
+
+ /* Find the longest match for the current string position,
+ * among tokens in the given block */
+ ctx->longest_match = 0;
+ result = REGEX_ITERNAL_block_iterate (block, size,
+ ®ex_edge_iterator, ctx);
+ GNUNET_break (GNUNET_OK == result);
+
+ /* Did anything match? */
+ if (0 == ctx->longest_match)
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG, " no match in block\n");
+ return;
+ }
+
+ hash = &ctx->hash;
+ new_ctx = GNUNET_malloc (sizeof (struct RegexSearchContext));
+ new_ctx->info = info;
+ new_ctx->position = ctx->position + ctx->longest_match;
+ GNUNET_array_append (info->contexts, info->n_contexts, new_ctx);
+
+ /* Check whether we already have a DHT GET running for it */
+ if (GNUNET_YES ==
+ GNUNET_CONTAINER_multihashmap_contains (info->dht_get_handles, hash))
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "* GET for %s running, END\n",
+ GNUNET_h2s (hash));
+ GNUNET_CONTAINER_multihashmap_get_multiple (info->dht_get_results,
+ hash,
+ ®ex_result_iterator,
+ new_ctx);
+ return; /* We are already looking for it */
+ }
+
+ GNUNET_STATISTICS_update (info->stats, "# regex nodes traversed",
+ 1, GNUNET_NO);
+
+ /* Start search in DHT */
+ LOG (GNUNET_ERROR_TYPE_INFO, " looking for %s\n", GNUNET_h2s (hash));
+ rest = &new_ctx->info->description[new_ctx->position];
+ get_h =
+ GNUNET_DHT_get_start (info->dht, /* handle */
+ GNUNET_BLOCK_TYPE_REGEX, /* type */
+ hash, /* key to search */
+ DHT_REPLICATION, /* replication level */
+ DHT_OPT,
+ rest, /* xquery */
+ // FIXME add BLOOMFILTER to exclude filtered peers
+ strlen(rest) + 1, /* xquery bits */
+ // FIXME add BLOOMFILTER SIZE
+ &dht_get_string_handler, new_ctx);
+ if (GNUNET_OK !=
+ GNUNET_CONTAINER_multihashmap_put(info->dht_get_handles,
+ hash,
+ get_h,
+
GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
+ {
+ GNUNET_break (0);
+ return;
+ }
+}
+
+
+struct REGEX_ITERNAL_Search *
+REGEX_ITERNAL_search (struct GNUNET_DHT_Handle *dht,
+ const char *string,
+ REGEX_ITERNAL_Found callback,
+ void *callback_cls,
+ struct GNUNET_STATISTICS_Handle *stats)
+{
+ struct REGEX_ITERNAL_Search *h;
+ struct GNUNET_DHT_GetHandle *get_h;
+ struct RegexSearchContext *ctx;
+ struct GNUNET_HashCode key;
+ size_t size;
+ size_t len;
+
+ /* Initialize handle */
+ LOG (GNUNET_ERROR_TYPE_INFO, "REGEX_ITERNAL_search: %s\n", string);
+ GNUNET_assert (NULL != dht);
+ GNUNET_assert (NULL != callback);
+ h = GNUNET_malloc (sizeof (struct REGEX_ITERNAL_Search));
+ h->dht = dht;
+ h->description = GNUNET_strdup (string);
+ h->callback = callback;
+ h->callback_cls = callback_cls;
+ h->stats = stats;
+ h->dht_get_handles = GNUNET_CONTAINER_multihashmap_create (32, GNUNET_NO);
+ h->dht_get_results = GNUNET_CONTAINER_multihashmap_create (32, GNUNET_YES);
+
+ /* Initialize context */
+ len = strlen (string);
+ size = REGEX_ITERNAL_get_first_key (string, len, &key);
+ ctx = GNUNET_malloc (sizeof (struct RegexSearchContext));
+ ctx->position = size;
+ ctx->info = h;
+ GNUNET_array_append (h->contexts, h->n_contexts, ctx);
+ LOG (GNUNET_ERROR_TYPE_DEBUG, " consumed %u bits out of %u\n", size, len);
+ LOG (GNUNET_ERROR_TYPE_INFO, " looking for %s\n", GNUNET_h2s (&key));
+
+ /* Start search in DHT */
+ get_h = GNUNET_DHT_get_start (h->dht, /* handle */
+ GNUNET_BLOCK_TYPE_REGEX, /* type */
+ &key, /* key to search */
+ DHT_REPLICATION, /* replication level */
+ DHT_OPT,
+ &h->description[size], /* xquery */
+ // FIXME add BLOOMFILTER to exclude filtered
peers
+ len + 1 - size, /* xquery bits
*/
+ // FIXME add BLOOMFILTER SIZE
+ &dht_get_string_handler, ctx);
+ GNUNET_break (
+ GNUNET_OK ==
+ GNUNET_CONTAINER_multihashmap_put (h->dht_get_handles,
+ &key,
+ get_h,
+
GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST)
+ );
+
+ return h;
+}
+
+
+/**
+ * Iterator over hash map entries to cancel DHT GET requests after a
+ * successful connect_by_string.
+ *
+ * @param cls Closure (unused).
+ * @param key Current key code (unused).
+ * @param value Value in the hash map (get handle).
+ * @return GNUNET_YES if we should continue to iterate,
+ * GNUNET_NO if not.
+ */
+static int
+regex_cancel_dht_get (void *cls,
+ const struct GNUNET_HashCode * key,
+ void *value)
+{
+ struct GNUNET_DHT_GetHandle *h = value;
+
+ GNUNET_DHT_get_stop (h);
+ return GNUNET_YES;
+}
+
+
+/**
+ * Iterator over hash map entries to free MeshRegexBlocks stored during the
+ * search for connect_by_string.
+ *
+ * @param cls Closure (unused).
+ * @param key Current key code (unused).
+ * @param value MeshRegexBlock in the hash map.
+ * @return GNUNET_YES if we should continue to iterate,
+ * GNUNET_NO if not.
+ */
+static int
+regex_free_result (void *cls,
+ const struct GNUNET_HashCode * key,
+ void *value)
+{
+
+ GNUNET_free (value);
+ return GNUNET_YES;
+}
+
+
+/**
+ * Cancel an ongoing regex search in the DHT and free all resources.
+ *
+ * @param ctx The search context.
+ */
+static void
+regex_cancel_search (struct REGEX_ITERNAL_Search *ctx)
+{
+ GNUNET_free (ctx->description);
+ GNUNET_CONTAINER_multihashmap_iterate (ctx->dht_get_handles,
+ ®ex_cancel_dht_get, NULL);
+ GNUNET_CONTAINER_multihashmap_iterate (ctx->dht_get_results,
+ ®ex_free_result, NULL);
+ GNUNET_CONTAINER_multihashmap_destroy (ctx->dht_get_results);
+ GNUNET_CONTAINER_multihashmap_destroy (ctx->dht_get_handles);
+ if (0 < ctx->n_contexts)
+ {
+ int i;
+
+ for (i = 0; i < ctx->n_contexts; i++)
+ {
+ GNUNET_free (ctx->contexts[i]);
+ }
+ GNUNET_free (ctx->contexts);
+ }
+}
+
+void
+REGEX_ITERNAL_search_cancel (struct REGEX_ITERNAL_Search *h)
+{
+ regex_cancel_search (h);
+ GNUNET_free (h);
+}
+
+
+
+/* end of regex_dht.c */
Modified: gnunet/src/regex/regex_internal_lib.h
===================================================================
--- gnunet/src/regex/regex_internal_lib.h 2013-06-20 08:32:50 UTC (rev
27498)
+++ gnunet/src/regex/regex_internal_lib.h 2013-06-20 08:55:56 UTC (rev
27499)
@@ -21,7 +21,6 @@
* @file regex/regex_internal_lib.h
* @brief library to parse regular expressions into dfa
* @author Maximilian Szengel
- *
*/
#ifndef REGEX_INTERNAL_LIB_H
@@ -40,11 +39,9 @@
#endif
-
-
/**
* Automaton (NFA/DFA) representation.
-- */
+ */
struct REGEX_ITERNAL_Automaton;
@@ -98,44 +95,6 @@
/**
- * Options for graph creation function
- * REGEX_ITERNAL_automaton_save_graph.
- */
-enum REGEX_ITERNAL_GraphSavingOptions
-{
- /**
- * Default. Do nothing special.
- */
- REGEX_ITERNAL_GRAPH_DEFAULT = 0,
-
- /**
- * The generated graph will include extra information such as the NFA states
- * that were used to generate the DFA state.
- */
- REGEX_ITERNAL_GRAPH_VERBOSE = 1,
-
- /**
- * Enable graph coloring. Will color each SCC in a different color.
- */
- REGEX_ITERNAL_GRAPH_COLORING = 2
-};
-
-
-/**
- * Save the given automaton as a GraphViz dot file.
- *
- * @param a the automaton to be saved.
- * @param filename where to save the file.
- * @param options options for graph generation that include coloring or verbose
- * mode
- */
-void
-REGEX_ITERNAL_automaton_save_graph (struct REGEX_ITERNAL_Automaton *a,
- const char *filename,
- enum REGEX_ITERNAL_GraphSavingOptions
options);
-
-
-/**
* Evaluates the given 'string' against the given compiled regex.
*
* @param a automaton.
Deleted: gnunet/src/regex/regex_random.c
===================================================================
--- gnunet/src/regex/regex_random.c 2013-06-20 08:32:50 UTC (rev 27498)
+++ gnunet/src/regex/regex_random.c 2013-06-20 08:55:56 UTC (rev 27499)
@@ -1,170 +0,0 @@
-/*
- This file is part of GNUnet
- (C) 2012 Christian Grothoff (and other contributing authors)
-
- GNUnet is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published
- by the Free Software Foundation; either version 3, or (at your
- option) any later version.
-
- GNUnet is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with GNUnet; see the file COPYING. If not, write to the
- Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA.
-*/
-/**
- * @file src/regex/regex_random.c
- * @brief functions for creating random regular expressions and strings
- * @author Maximilian Szengel
- */
-#include "platform.h"
-#include "regex_internal_lib.h"
-#include "gnunet_crypto_lib.h"
-#include "regex_internal.h"
-
-
-/**
- * Get a (pseudo) random valid literal for building a regular expression.
- *
- * @return random valid literal
- */
-char
-get_random_literal ()
-{
- uint32_t ridx;
-
- ridx =
- GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
- (uint32_t) strlen (ALLOWED_LITERALS));
-
- return ALLOWED_LITERALS[ridx];
-}
-
-
-/**
- * Generate a (pseudo) random regular expression of length 'rx_length', as well
- * as a (optional) string that will be matched by the generated regex. The
- * returned regex needs to be freed.
- *
- * @param rx_length length of the random regex.
- * @param matching_str (optional) pointer to a string that will contain a
string
- * that will be matched by the generated regex, if
- * 'matching_str' pointer was not NULL. Make sure you
- * allocated at least rx_length+1 bytes for this sting.
- *
- * @return NULL if 'rx_length' is 0, a random regex of length 'rx_length',
which
- * needs to be freed, otherwise.
- */
-char *
-REGEX_ITERNAL_generate_random_regex (size_t rx_length, char *matching_str)
-{
- char *rx;
- char *rx_p;
- char *matching_strp;
- unsigned int i;
- unsigned int char_op_switch;
- unsigned int last_was_op;
- int rx_op;
- char current_char;
-
- if (0 == rx_length)
- return NULL;
-
- if (NULL != matching_str)
- matching_strp = matching_str;
- else
- matching_strp = NULL;
-
- rx = GNUNET_malloc (rx_length + 1);
- rx_p = rx;
- current_char = 0;
- last_was_op = 1;
-
- for (i = 0; i < rx_length; i++)
- {
- char_op_switch = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, 2);
-
- if (0 == char_op_switch && !last_was_op)
- {
- last_was_op = 1;
- rx_op = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, 4);
-
- switch (rx_op)
- {
- case 0:
- current_char = '+';
- break;
- case 1:
- current_char = '*';
- break;
- case 2:
- current_char = '?';
- break;
- case 3:
- if (i < rx_length - 1) /* '|' cannot be at the end */
- current_char = '|';
- else
- current_char = get_random_literal ();
- break;
- }
- }
- else
- {
- current_char = get_random_literal ();
- last_was_op = 0;
- }
-
- if (NULL != matching_strp &&
- (current_char != '+' && current_char != '*' && current_char != '?' &&
- current_char != '|'))
- {
- *matching_strp = current_char;
- matching_strp++;
- }
-
- *rx_p = current_char;
- rx_p++;
- }
- *rx_p = '\0';
- if (NULL != matching_strp)
- *matching_strp = '\0';
-
- return rx;
-}
-
-/**
- * Generate a random string of maximum length 'max_len' that only contains
literals allowed
- * in a regular expression. The string might be 0 chars long but is garantueed
- * to be shorter or equal to 'max_len'.
- *
- * @param max_len maximum length of the string that should be generated.
- *
- * @return random string that needs to be freed.
- */
-char *
-REGEX_ITERNAL_generate_random_string (size_t max_len)
-{
- unsigned int i;
- char *str;
- size_t len;
-
- if (1 > max_len)
- return GNUNET_strdup ("");
-
- len = (size_t) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
max_len);
- str = GNUNET_malloc (len + 1);
-
- for (i = 0; i < len; i++)
- {
- str[i] = get_random_literal ();
- }
-
- str[i] = '\0';
-
- return str;
-}
Copied: gnunet/src/regex/regex_test_graph.c (from rev 27498,
gnunet/src/regex/regex_graph.c)
===================================================================
--- gnunet/src/regex/regex_test_graph.c (rev 0)
+++ gnunet/src/regex/regex_test_graph.c 2013-06-20 08:55:56 UTC (rev 27499)
@@ -0,0 +1,318 @@
+/*
+ This file is part of GNUnet
+ (C) 2012 Christian Grothoff (and other contributing authors)
+
+ GNUnet is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published
+ by the Free Software Foundation; either version 3, or (at your
+ option) any later version.
+
+ GNUnet is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GNUnet; see the file COPYING. If not, write to the
+ Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA.
+*/
+/**
+ * @file src/regex/regex_test_graph.c
+ * @brief functions for creating .dot graphs from regexes
+ * @author Maximilian Szengel
+ */
+#include "platform.h"
+#include "regex_internal_lib.h"
+#include "regex_test_lib.h"
+#include "regex_internal.h"
+
+/**
+ * Context for graph creation. Passed as the cls to
+ * REGEX_ITERNAL_automaton_save_graph_step.
+ */
+struct REGEX_ITERNAL_Graph_Context
+{
+ /**
+ * File pointer to the dot file used for output.
+ */
+ FILE *filep;
+
+ /**
+ * Verbose flag, if it's set to GNUNET_YES additional info will be printed in
+ * the graph.
+ */
+ int verbose;
+
+ /**
+ * Coloring flag, if set to GNUNET_YES SCCs will be colored.
+ */
+ int coloring;
+};
+
+
+/**
+ * Recursive function doing DFS with 'v' as a start, detecting all SCCs inside
+ * the subgraph reachable from 'v'. Used with scc_tarjan function to detect all
+ * SCCs inside an automaton.
+ *
+ * @param scc_counter counter for numbering the sccs
+ * @param v start vertex
+ * @param index current index
+ * @param stack stack for saving all SCCs
+ * @param stack_size current size of the stack
+ */
+static void
+scc_tarjan_strongconnect (unsigned int *scc_counter,
+ struct REGEX_ITERNAL_State *v, unsigned int *index,
+ struct REGEX_ITERNAL_State **stack,
+ unsigned int *stack_size)
+{
+ struct REGEX_ITERNAL_State *w;
+ struct REGEX_ITERNAL_Transition *t;
+
+ v->index = *index;
+ v->lowlink = *index;
+ (*index)++;
+ stack[(*stack_size)++] = v;
+ v->contained = 1;
+
+ for (t = v->transitions_head; NULL != t; t = t->next)
+ {
+ w = t->to_state;
+
+ if (NULL == w)
+ continue;
+
+ if (w->index < 0)
+ {
+ scc_tarjan_strongconnect (scc_counter, w, index, stack, stack_size);
+ v->lowlink = (v->lowlink > w->lowlink) ? w->lowlink : v->lowlink;
+ }
+ else if (1 == w->contained)
+ v->lowlink = (v->lowlink > w->index) ? w->index : v->lowlink;
+ }
+
+ if (v->lowlink == v->index)
+ {
+ (*scc_counter)++;
+ do
+ {
+ w = stack[--(*stack_size)];
+ w->contained = 0;
+ w->scc_id = *scc_counter;
+ }
+ while (w != v);
+ }
+}
+
+
+/**
+ * Detect all SCCs (Strongly Connected Components) inside the given automaton.
+ * SCCs will be marked using the scc_id on each state.
+ *
+ * @param a the automaton for which SCCs should be computed and assigned.
+ */
+static void
+scc_tarjan (struct REGEX_ITERNAL_Automaton *a)
+{
+ unsigned int index;
+ unsigned int scc_counter;
+ struct REGEX_ITERNAL_State *v;
+ struct REGEX_ITERNAL_State *stack[a->state_count];
+ unsigned int stack_size;
+
+ for (v = a->states_head; NULL != v; v = v->next)
+ {
+ v->contained = 0;
+ v->index = -1;
+ v->lowlink = -1;
+ }
+
+ stack_size = 0;
+ index = 0;
+ scc_counter = 0;
+
+ for (v = a->states_head; NULL != v; v = v->next)
+ {
+ if (v->index < 0)
+ scc_tarjan_strongconnect (&scc_counter, v, &index, stack, &stack_size);
+ }
+}
+
+
+/**
+ * Save a state to an open file pointer. cls is expected to be a file pointer
to
+ * an open file. Used only in conjunction with
+ * REGEX_ITERNAL_automaton_save_graph.
+ *
+ * @param cls file pointer.
+ * @param count current count of the state, not used.
+ * @param s state.
+ */
+void
+REGEX_ITERNAL_automaton_save_graph_step (void *cls, unsigned int count,
+ struct REGEX_ITERNAL_State *s)
+{
+ struct REGEX_ITERNAL_Graph_Context *ctx = cls;
+ struct REGEX_ITERNAL_Transition *ctran;
+ char *s_acc = NULL;
+ char *s_tran = NULL;
+ char *name;
+ char *to_name;
+
+ if (GNUNET_YES == ctx->verbose)
+ GNUNET_asprintf (&name, "%i (%s) (%s) (%s)", s->dfs_id, s->name, s->proof,
+ GNUNET_h2s (&s->hash));
+ else
+ GNUNET_asprintf (&name, "%i", s->dfs_id);
+
+ if (s->accepting)
+ {
+ if (GNUNET_YES == ctx->coloring)
+ {
+ GNUNET_asprintf (&s_acc,
+ "\"%s\" [shape=doublecircle, color=\"0.%i 0.8
0.95\"];\n",
+ name, s->scc_id * s->scc_id);
+ }
+ else
+ {
+ GNUNET_asprintf (&s_acc, "\"%s\" [shape=doublecircle];\n", name,
+ s->scc_id);
+ }
+ }
+ else if (GNUNET_YES == ctx->coloring)
+ {
+ GNUNET_asprintf (&s_acc,
+ "\"%s\" [shape=circle, color=\"0.%i 0.8 0.95\"];\n", name,
+ s->scc_id * s->scc_id);
+ }
+ else
+ {
+ GNUNET_asprintf (&s_acc, "\"%s\" [shape=circle];\n", name, s->scc_id);
+ }
+
+ GNUNET_assert (NULL != s_acc);
+
+ fwrite (s_acc, strlen (s_acc), 1, ctx->filep);
+ GNUNET_free (s_acc);
+ s_acc = NULL;
+
+ for (ctran = s->transitions_head; NULL != ctran; ctran = ctran->next)
+ {
+ if (NULL == ctran->to_state)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "Transition from State %i has no state for transitioning\n",
+ s->id);
+ continue;
+ }
+
+ if (GNUNET_YES == ctx->verbose)
+ {
+ GNUNET_asprintf (&to_name, "%i (%s) (%s) (%s)", ctran->to_state->dfs_id,
+ ctran->to_state->name, ctran->to_state->proof,
+ GNUNET_h2s (&ctran->to_state->hash));
+ }
+ else
+ GNUNET_asprintf (&to_name, "%i", ctran->to_state->dfs_id);
+
+ if (NULL == ctran->label)
+ {
+ if (GNUNET_YES == ctx->coloring)
+ {
+ GNUNET_asprintf (&s_tran,
+ "\"%s\" -> \"%s\" [label = \"ε\", color=\"0.%i 0.8
0.95\"];\n",
+ name, to_name, s->scc_id * s->scc_id);
+ }
+ else
+ {
+ GNUNET_asprintf (&s_tran, "\"%s\" -> \"%s\" [label = \"ε\"];\n", name,
+ to_name, s->scc_id);
+ }
+ }
+ else
+ {
+ if (GNUNET_YES == ctx->coloring)
+ {
+ GNUNET_asprintf (&s_tran,
+ "\"%s\" -> \"%s\" [label = \"%s\", color=\"0.%i 0.8
0.95\"];\n",
+ name, to_name, ctran->label, s->scc_id * s->scc_id);
+ }
+ else
+ {
+ GNUNET_asprintf (&s_tran, "\"%s\" -> \"%s\" [label = \"%s\"];\n", name,
+ to_name, ctran->label, s->scc_id);
+ }
+ }
+
+ GNUNET_free (to_name);
+
+ GNUNET_assert (NULL != s_tran);
+
+ fwrite (s_tran, strlen (s_tran), 1, ctx->filep);
+ GNUNET_free (s_tran);
+ s_tran = NULL;
+ }
+
+ GNUNET_free (name);
+}
+
+
+/**
+ * Save the given automaton as a GraphViz dot file.
+ *
+ * @param a the automaton to be saved.
+ * @param filename where to save the file.
+ * @param options options for graph generation that include coloring or verbose
+ * mode
+ */
+void
+REGEX_ITERNAL_automaton_save_graph (struct REGEX_ITERNAL_Automaton *a,
+ const char *filename,
+ enum REGEX_ITERNAL_GraphSavingOptions
options)
+{
+ char *start;
+ char *end;
+ struct REGEX_ITERNAL_Graph_Context ctx;
+
+ if (NULL == a)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Could not print NFA, was NULL!");
+ return;
+ }
+
+ if (NULL == filename || strlen (filename) < 1)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No Filename given!");
+ return;
+ }
+
+ ctx.filep = fopen (filename, "w");
+ ctx.verbose =
+ (0 == (options & REGEX_ITERNAL_GRAPH_VERBOSE)) ? GNUNET_NO : GNUNET_YES;
+ ctx.coloring =
+ (0 == (options & REGEX_ITERNAL_GRAPH_COLORING)) ? GNUNET_NO : GNUNET_YES;
+
+ if (NULL == ctx.filep)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Could not open file for writing: %s",
+ filename);
+ return;
+ }
+
+ /* First add the SCCs to the automaton, so we can color them nicely */
+ if (GNUNET_YES == ctx.coloring)
+ scc_tarjan (a);
+
+ start = "digraph G {\nrankdir=LR\n";
+ fwrite (start, strlen (start), 1, ctx.filep);
+
+ REGEX_ITERNAL_automaton_traverse (a, a->start, NULL, NULL,
+ ®EX_ITERNAL_automaton_save_graph_step,
+ &ctx);
+
+ end = "\n}\n";
+ fwrite (end, strlen (end), 1, ctx.filep);
+ fclose (ctx.filep);
+}
Modified: gnunet/src/regex/regex_test_lib.h
===================================================================
--- gnunet/src/regex/regex_test_lib.h 2013-06-20 08:32:50 UTC (rev 27498)
+++ gnunet/src/regex/regex_test_lib.h 2013-06-20 08:55:56 UTC (rev 27499)
@@ -20,15 +20,15 @@
/**
* @file src/regex/regex_test_lib.h
* @brief library to read regexes representing IP networks from a file.
- * and simplyfinying the into one big regex, in order to run
- * tests (regex performance, mesh profiler).
+ * and simplifying the into one big regex, in order to run
+ * tests (regex performance, regex profiler).
* @author Bertlomiej Polot
- *
*/
#ifndef REGEX_ITERNAL_TEST_LIB_H
#define REGEX_ITERNAL_TEST_LIB_H
+#include "regex_internal_lib.h"
#ifdef __cplusplus
extern "C"
@@ -48,6 +48,7 @@
char *
REGEX_ITERNAL_combine(char * const regexes[]);
+
/**
* Read a set of regexes from a file, one per line and return them in an array
* suitable for REGEX_ITERNAL_combine.
@@ -69,6 +70,76 @@
void
REGEX_ITERNAL_free_from_file (char **regexes);
+
+/**
+ * Generate a (pseudo) random regular expression of length 'rx_length', as well
+ * as a (optional) string that will be matched by the generated regex. The
+ * returned regex needs to be freed.
+ *
+ * @param rx_length length of the random regex.
+ * @param matching_str (optional) pointer to a string that will contain a
string
+ * that will be matched by the generated regex, if
+ * 'matching_str' pointer was not NULL.
+ *
+ * @return NULL if 'rx_length' is 0, a random regex of length 'rx_length',
which
+ * needs to be freed, otherwise.
+ */
+char *
+REGEX_ITERNAL_generate_random_regex (size_t rx_length, char *matching_str);
+
+
+/**
+ * Generate a random string of maximum length 'max_len' that only contains
literals allowed
+ * in a regular expression. The string might be 0 chars long but is garantueed
+ * to be shorter or equal to 'max_len'.
+ *
+ * @param max_len maximum length of the string that should be generated.
+ *
+ * @return random string that needs to be freed.
+ */
+char *
+REGEX_ITERNAL_generate_random_string (size_t max_len);
+
+
+/**
+ * Options for graph creation function
+ * REGEX_ITERNAL_automaton_save_graph.
+ */
+enum REGEX_ITERNAL_GraphSavingOptions
+{
+ /**
+ * Default. Do nothing special.
+ */
+ REGEX_ITERNAL_GRAPH_DEFAULT = 0,
+
+ /**
+ * The generated graph will include extra information such as the NFA states
+ * that were used to generate the DFA state.
+ */
+ REGEX_ITERNAL_GRAPH_VERBOSE = 1,
+
+ /**
+ * Enable graph coloring. Will color each SCC in a different color.
+ */
+ REGEX_ITERNAL_GRAPH_COLORING = 2
+};
+
+
+/**
+ * Save the given automaton as a GraphViz dot file.
+ *
+ * @param a the automaton to be saved.
+ * @param filename where to save the file.
+ * @param options options for graph generation that include coloring or verbose
+ * mode
+ */
+void
+REGEX_ITERNAL_automaton_save_graph (struct REGEX_ITERNAL_Automaton *a,
+ const char *filename,
+ enum REGEX_ITERNAL_GraphSavingOptions
options);
+
+
+
#if 0 /* keep Emacsens' auto-indent happy */
{
#endif
@@ -77,4 +148,4 @@
#endif
/* end of regex_internal_lib.h */
-#endif
\ No newline at end of file
+#endif
Copied: gnunet/src/regex/regex_test_random.c (from rev 27498,
gnunet/src/regex/regex_random.c)
===================================================================
--- gnunet/src/regex/regex_test_random.c (rev 0)
+++ gnunet/src/regex/regex_test_random.c 2013-06-20 08:55:56 UTC (rev
27499)
@@ -0,0 +1,171 @@
+/*
+ This file is part of GNUnet
+ (C) 2012 Christian Grothoff (and other contributing authors)
+
+ GNUnet is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published
+ by the Free Software Foundation; either version 3, or (at your
+ option) any later version.
+
+ GNUnet is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GNUnet; see the file COPYING. If not, write to the
+ Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA.
+*/
+/**
+ * @file src/regex/regex_test_random.c
+ * @brief functions for creating random regular expressions and strings
+ * @author Maximilian Szengel
+ */
+#include "platform.h"
+#include "regex_test_lib.h"
+#include "gnunet_crypto_lib.h"
+#include "regex_internal.h"
+
+
+/**
+ * Get a (pseudo) random valid literal for building a regular expression.
+ *
+ * @return random valid literal
+ */
+static char
+get_random_literal ()
+{
+ uint32_t ridx;
+
+ ridx =
+ GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
+ (uint32_t) strlen (ALLOWED_LITERALS));
+
+ return ALLOWED_LITERALS[ridx];
+}
+
+
+/**
+ * Generate a (pseudo) random regular expression of length 'rx_length', as well
+ * as a (optional) string that will be matched by the generated regex. The
+ * returned regex needs to be freed.
+ *
+ * @param rx_length length of the random regex.
+ * @param matching_str (optional) pointer to a string that will contain a
string
+ * that will be matched by the generated regex, if
+ * 'matching_str' pointer was not NULL. Make sure you
+ * allocated at least rx_length+1 bytes for this sting.
+ *
+ * @return NULL if 'rx_length' is 0, a random regex of length 'rx_length',
which
+ * needs to be freed, otherwise.
+ */
+char *
+REGEX_ITERNAL_generate_random_regex (size_t rx_length, char *matching_str)
+{
+ char *rx;
+ char *rx_p;
+ char *matching_strp;
+ unsigned int i;
+ unsigned int char_op_switch;
+ unsigned int last_was_op;
+ int rx_op;
+ char current_char;
+
+ if (0 == rx_length)
+ return NULL;
+
+ if (NULL != matching_str)
+ matching_strp = matching_str;
+ else
+ matching_strp = NULL;
+
+ rx = GNUNET_malloc (rx_length + 1);
+ rx_p = rx;
+ current_char = 0;
+ last_was_op = 1;
+
+ for (i = 0; i < rx_length; i++)
+ {
+ char_op_switch = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, 2);
+
+ if (0 == char_op_switch && !last_was_op)
+ {
+ last_was_op = 1;
+ rx_op = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, 4);
+
+ switch (rx_op)
+ {
+ case 0:
+ current_char = '+';
+ break;
+ case 1:
+ current_char = '*';
+ break;
+ case 2:
+ current_char = '?';
+ break;
+ case 3:
+ if (i < rx_length - 1) /* '|' cannot be at the end */
+ current_char = '|';
+ else
+ current_char = get_random_literal ();
+ break;
+ }
+ }
+ else
+ {
+ current_char = get_random_literal ();
+ last_was_op = 0;
+ }
+
+ if (NULL != matching_strp &&
+ (current_char != '+' && current_char != '*' && current_char != '?' &&
+ current_char != '|'))
+ {
+ *matching_strp = current_char;
+ matching_strp++;
+ }
+
+ *rx_p = current_char;
+ rx_p++;
+ }
+ *rx_p = '\0';
+ if (NULL != matching_strp)
+ *matching_strp = '\0';
+
+ return rx;
+}
+
+
+/**
+ * Generate a random string of maximum length 'max_len' that only contains
literals allowed
+ * in a regular expression. The string might be 0 chars long but is garantueed
+ * to be shorter or equal to 'max_len'.
+ *
+ * @param max_len maximum length of the string that should be generated.
+ *
+ * @return random string that needs to be freed.
+ */
+char *
+REGEX_ITERNAL_generate_random_string (size_t max_len)
+{
+ unsigned int i;
+ char *str;
+ size_t len;
+
+ if (1 > max_len)
+ return GNUNET_strdup ("");
+
+ len = (size_t) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
max_len);
+ str = GNUNET_malloc (len + 1);
+
+ for (i = 0; i < len; i++)
+ {
+ str[i] = get_random_literal ();
+ }
+
+ str[i] = '\0';
+
+ return str;
+}
Modified: gnunet/src/regex/test_regex_eval_api.c
===================================================================
--- gnunet/src/regex/test_regex_eval_api.c 2013-06-20 08:32:50 UTC (rev
27498)
+++ gnunet/src/regex/test_regex_eval_api.c 2013-06-20 08:55:56 UTC (rev
27499)
@@ -26,6 +26,7 @@
#include <time.h>
#include "platform.h"
#include "regex_internal_lib.h"
+#include "regex_test_lib.h"
#include "regex_internal.h"
enum Match_Result
Modified: gnunet/src/regex/test_regex_graph_api.c
===================================================================
--- gnunet/src/regex/test_regex_graph_api.c 2013-06-20 08:32:50 UTC (rev
27498)
+++ gnunet/src/regex/test_regex_graph_api.c 2013-06-20 08:55:56 UTC (rev
27499)
@@ -26,6 +26,7 @@
#include <time.h>
#include "platform.h"
#include "regex_internal_lib.h"
+#include "regex_test_lib.h"
#include "regex_internal.h"
#define KEEP_FILES 1
Modified: gnunet/src/regex/test_regex_proofs.c
===================================================================
--- gnunet/src/regex/test_regex_proofs.c 2013-06-20 08:32:50 UTC (rev
27498)
+++ gnunet/src/regex/test_regex_proofs.c 2013-06-20 08:55:56 UTC (rev
27499)
@@ -24,6 +24,7 @@
*/
#include "platform.h"
#include "regex_internal_lib.h"
+#include "regex_test_lib.h"
#include "regex_internal.h"
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