[PATCH] dfa: improve documentation of struct dfa

[Paolo Bonzini]

* src/dfa.h (struct dfa): Reword some comments.
---
 src/dfa.h |   29 ++++++++++++++++-------------
 1 files changed, 16 insertions(+), 13 deletions(-)

diff --git a/src/dfa.h b/src/dfa.h
index 4ca55f0..effb47a 100644
--- a/src/dfa.h
+++ b/src/dfa.h
@@ -261,12 +261,12 @@ struct mb_char_classes
 /* A compiled regular expression. */
 struct dfa
 {
-  /* Stuff built by the scanner. */
+  /* Fields filled by the scanner. */
   charclass *charclasses;      /* Array of character sets for CSET tokens. */
   int cindex;                  /* Index for adding new charclasses. */
   int calloc;                  /* Number of charclasses currently allocated. */
 
-  /* Stuff built by the parser. */
+  /* Fields filled by the parser. */
   token *tokens;               /* Postfix parse array. */
   int tindex;                  /* Index for adding new tokens. */
   int talloc;                  /* Number of tokens currently allocated. */
@@ -277,15 +277,15 @@ struct dfa
   int nregexps;                        /* Count of parallel regexps being built
                                   with dfaparse(). */
 #ifdef MBS_SUPPORT
-  /* These stuff are used only if MB_CUR_MAX > 1 or multibyte environments.  */
-  int nmultibyte_prop;
-  int *multibyte_prop;
+  /* The following are used only if MB_CUR_MAX > 1.  */
+
   /* The value of multibyte_prop[i] is defined by following rule.
        if tokens[i] < NOTCHAR
-         bit 1 : tokens[i] is a single byte character, or the last-byte of
-                a multibyte character.
-        bit 0 : tokens[i] is a single byte character, or the 1st-byte of
-                a multibyte character.
+         bit 0 : tokens[i] is the first byte of a character, including
+                 single-byte characters.
+         bit 1 : tokens[i] is the last byte of a character, including
+                 single-byte characters.
+
        if tokens[i] = MBCSET
          ("the index of mbcsets correspnd to this operator" << 2) + 3
 
@@ -296,19 +296,21 @@ struct dfa
      multibyte_prop
         = 3     , 1               ,  0              ,  2              , 3
   */
+  int nmultibyte_prop;
+  int *multibyte_prop;
 
-  /* Array of the bracket expressoin in the DFA.  */
+  /* Array of the bracket expression in the DFA.  */
   struct mb_char_classes *mbcsets;
   int nmbcsets;
   int mbcsets_alloc;
 #endif
 
-  /* Stuff owned by the state builder. */
+  /* Fields filled by the state builder. */
   dfa_state *states;           /* States of the dfa. */
   int sindex;                  /* Index for adding new states. */
   int salloc;                  /* Number of states currently allocated. */
 
-  /* Stuff built by the structure analyzer. */
+  /* Fields filled by the parse tree->NFA conversion. */
   position_set *follows;       /* Array of follow sets, indexed by position
                                   index.  The follow of a position is the set
                                   of positions containing characters that
@@ -324,7 +326,7 @@ struct dfa
                                   string matching, but anchored to the
                                   beginning of the buffer. */
 
-  /* Stuff owned by the executor. */
+  /* Fields filled by dfaexec. */
   int tralloc;                 /* Number of transition tables that have
                                   slots so far. */
   int trcount;                 /* Number of transition tables that have
@@ -349,6 +351,7 @@ struct dfa
   struct dfamust *musts;       /* List of strings, at least one of which
                                   is known to appear in any r.e. matching
                                   the dfa. */
+
 #ifdef GAWK
   int broken;                  /* True if using a feature where there
                                   are bugs and gawk should use regex. */
-- 
1.6.6.1