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Re: userspec fixes for coreutils (e.g., "chown 010 file")
|
From: |
Paul Eggert |
|
Subject: |
Re: userspec fixes for coreutils (e.g., "chown 010 file") |
|
Date: |
Thu, 19 Aug 2004 13:17:29 -0700 |
|
User-agent: |
Gnus/5.1006 (Gnus v5.10.6) Emacs/21.3 (gnu/linux) |
"Dmitry V. Levin" <address@hidden> writes:
> $ chown "`id -u`.`id -g`" .
> chown: `567.567': invalid user
> $ chown "`id -un`.`id -gn`" .
> chown: `me.me': invalid user
>
> Proposed fix along with new testcase is attached.
Thanks for finding that. While looking at your patch, I noticed a
similar problem with invalid numeric groups. The code is pretty
crufty with that weird goto (and I think I wrote some of it -- sorry!)
and this cruftiness contributed to the bug. Also, this reminded me of
a BSD-compatibility glitch in this area that I volunteered to fix in May
<http://lists.gnu.org/archive/html/bug-coreutils/2004-05/msg00174.html>.
I installed the following patch to try to fix all these problems at
once. It adds your test cases and a bunch of others (though probably
not enough :-).
2004-08-19 Paul Eggert <address@hidden>
* NEWS: "chown : file", "chown '' file", and "chgrp '' file" now
succeed without changing the uid and gid, like FreeBSD.
* src/chgrp.c (parse_group): Return gid_t rather than storing it
through a pointer. Treat "chgrp '' file" as a no-op change,
as FreeBSD does.
(main): Set chopt.group_name to NULL if the group is the empty
string.
* src/chown-core.c (describe_change): Describe changes to -1:-1
without using "to OWNERSHIP" phrase.
* src/chown.c (usage): "chown '' file" is now allowed.
(main): Do not set user name to the empty string if the group
name is null.
* tests/chgrp/basic: Test "chgrp '' file".
* tests/chown/Makefile.am (TESTS): Add separator.
* tests/chown/separator: New file, partly taken from
Dmitry V. Levin's suggestion in
<http://lists.gnu.org/archive/html/bug-coreutils/2004-08/msg00102.html>
* doc/coreutils.texi (chown invocation): Fix synopsis:
group must always be preceded by separator.
"chown : file" and "chown '' file" don't change the owner or group.
Update the explanation of what happens to the set-user-ID or
set-group-ID bits, e.g., they sometimes are not cleared if they
denote mandatory locking. Change "find"-oriented examples to use
chown -h.
* lib/userspec.c: Don't use <alloca.h>, so that we don't use alloca on
strings on unbounded length. alloca's performance benefits aren't
that important here.
(V_STRDUP): Remove.
(parse_with_separator): New function, with most of the internals
of the old parse_user_spec. Allow user to omit both user and group,
for compatibility with FreeBSD.
Clone only the user name, not the entire spec.
Do not set *uid, *gid unless entirely successful.
Avoid memory leak in some failing cases.
Fix regression for USER.GROUP reported by Dmitry V. Levin in
<http://lists.gnu.org/archive/html/bug-coreutils/2004-08/msg00102.html>
(parse_user_spec): Rewrite to use parse_with_separator.
Index: NEWS
===================================================================
RCS file: /home/eggert/coreutils/cu/NEWS,v
retrieving revision 1.228
diff -p -u -r1.228 NEWS
--- NEWS 10 Aug 2004 22:05:47 -0000 1.228
+++ NEWS 19 Aug 2004 02:23:34 -0000
@@ -32,6 +32,9 @@ GNU coreutils NEWS
incorrect, as it failed to update the last-changed time and reset
special permission bits, as POSIX requires.
+ "chown : file", "chown '' file", and "chgrp '' file" now succeed
+ without changing the uid or gid, instead of reporting an error.
+
Do not report an error if the owner or group of a
recursively-encountered symbolic link cannot be updated because
the file system does not support it.
Index: doc/coreutils.texi
===================================================================
RCS file: /home/eggert/coreutils/cu/doc/coreutils.texi,v
retrieving revision 1.200
diff -p -u -r1.200 coreutils.texi
--- doc/coreutils.texi 18 Aug 2004 20:22:32 -0000 1.200
+++ doc/coreutils.texi 19 Aug 2004 03:05:37 -0000
@@ -7948,7 +7948,7 @@ If used, @var{new-owner} specifies the n
(with no embedded white space):
@example
address@hidden [ [:] address@hidden ]
address@hidden [ : address@hidden ]
@end example
Specifically:
@@ -7959,21 +7959,25 @@ If only an @var{owner} (a user name or n
user is made the owner of each given file, and the files' group is not
changed.
address@hidden address@hidden:}group
address@hidden address@hidden:}group
If the @var{owner} is followed by a colon and a @var{group} (a
group name or numeric group id), with no spaces between them, the group
ownership of the files is changed as well (to @var{group}).
address@hidden address@hidden:}
address@hidden address@hidden:}
If a colon but no group name follows @var{owner}, that user is
made the owner of the files and the group of the files is changed to
@var{owner}'s login group.
address@hidden @samp{:}group
address@hidden @samp{:}group
If the colon and following @var{group} are given, but the owner
is omitted, only the group of the files is changed; in this case,
@command{chown} performs the same function as @command{chgrp}.
address@hidden @samp{:}
+If only a colon is given, or if @var{new-owner} is empty, neither the
+owner nor the group is changed.
+
@end table
Some older scripts may still use @samp{.} in place of the @samp{:} separator.
@@ -7985,16 +7989,14 @@ portable, and because it has undesirable
@address@hidden happens to identify a user whose name
contains @samp{.}.
-Warning: The @command{chown} command may clear the set-user-ID or
-set-group-ID bits on some systems. The @command{chown} command is
-dependent upon the policy and functionality of the underlying system
-which may make system-dependent file mode modifications outside the
-control of the @command{chown} command. On some systems (e.g., Linux)
-the @command{chown} command clears the set-UID and set-GID bits because
-the underlying, system @code{chown} function clears them. On other
-systems (e.g., HP-UX and Solaris) the @command{chown} command does not
-affect those bits when operated as the superuser. On systems which allow
-non-privileged use of chown those bits are always cleared by the system.
+The @command{chown} command sometimes clears the set-user-ID or
+set-group-ID permission bits. This behavior depends on the policy and
+functionality of the underlying @code{chown} system call, which may
+make system-dependent file mode modifications outside the control of
+the @command{chown} command. For example, the @command{chown} command
+might not affect those bits when operated as the superuser, or if the
+bits signify some function other than executable permission (e.g.,
+mandatory locking).
When in doubt, check the underlying system behavior.
The program accepts the following options. Also see @ref{Common options}.
@@ -8031,7 +8033,7 @@ For example, to reflect a UID numbering
without an option like this, @code{root} might run
@smallexample
-find / -owner OLDUSER -print0 | xargs -0 chown NEWUSER
+find / -owner OLDUSER -print0 | xargs -0 chown -h NEWUSER
@end smallexample
But that is dangerous because the interval between when the @command{find}
@@ -8041,7 +8043,7 @@ One way to narrow the gap would be to in
as it is found:
@example
-find / -owner OLDUSER -exec chown NEWUSER @address@hidden \;
+find / -owner OLDUSER -exec chown -h NEWUSER @address@hidden \;
@end example
But that is very slow if there are many affected files.
@@ -8049,7 +8051,7 @@ With this option, it is safer (the gap i
though still not perfect:
@example
-chown -R --from=OLDUSER NEWUSER /
+chown -h -R --from=OLDUSER NEWUSER /
@end example
@item --dereference
Index: lib/userspec.c
===================================================================
RCS file: /home/eggert/coreutils/cu/lib/userspec.c,v
retrieving revision 1.43
diff -p -u -r1.43 userspec.c
--- lib/userspec.c 9 Aug 2004 18:44:50 -0000 1.43
+++ lib/userspec.c 19 Aug 2004 14:09:22 -0000
@@ -25,8 +25,6 @@
/* Specification. */
#include "userspec.h"
-#include <alloca.h>
-
#include <stdbool.h>
#include <stdio.h>
#include <sys/types.h>
@@ -92,18 +90,6 @@ struct group *getgrgid ();
# define MAXGID GID_T_MAX
#endif
-/* Perform the equivalent of the statement `dest = strdup (src);',
- but obtaining storage via alloca instead of from the heap. */
-
-#define V_STRDUP(dest, src) \
- do \
- { \
- size_t size = strlen (src) + 1; \
- (dest) = (char *) alloca (size); \
- memcpy (dest, src, size);
\
- } \
- while (0)
-
/* ISDIGIT differs from isdigit, as follows:
- Its arg may be any int or unsigned int; it need not be an unsigned char.
- It's guaranteed to evaluate its argument exactly once.
@@ -131,78 +117,52 @@ is_number (const char *str)
}
#endif
-/* Extract from NAME, which has the form "[user][:.][group]",
- a USERNAME, UID U, GROUPNAME, and GID G.
- Either user or group, or both, must be present.
- If the group is omitted but the ":" separator is given,
- use the given user's login group.
- If SPEC_ARG contains a `:', then use that as the separator, ignoring
- any `.'s. If there is no `:', but there is a `.', then first look
- up the entire SPEC_ARG as a login name. If that look-up fails, then
- try again interpreting the `.' as a separator.
-
- USERNAME and GROUPNAME will be in newly malloc'd memory.
- Either one might be NULL instead, indicating that it was not
- given and the corresponding numeric ID was left unchanged.
-
- Return NULL if successful, a static error message string if not. */
-
-const char *
-parse_user_spec (const char *spec_arg, uid_t *uid, gid_t *gid,
- char **username_arg, char **groupname_arg)
+static char const *
+parse_with_separator (char const *spec, char const *separator,
+ uid_t *uid, gid_t *gid,
+ char **username, char **groupname)
{
static const char *E_invalid_user = N_("invalid user");
static const char *E_invalid_group = N_("invalid group");
static const char *E_bad_spec =
N_("cannot get the login group of a numeric UID");
- static const char *E_cannot_omit_both =
- N_("cannot omit both user and group");
const char *error_msg;
- char *spec; /* A copy we can write on. */
struct passwd *pwd;
struct group *grp;
- char *g, *u, *separator;
- char *groupname;
- char *dot = NULL;
+ char *u;
+ char const *g;
+ char *gname = NULL;
+ uid_t unum = *uid;
+ gid_t gnum = *gid;
error_msg = NULL;
- *username_arg = *groupname_arg = NULL;
- groupname = NULL;
-
- V_STRDUP (spec, spec_arg);
+ *username = *groupname = NULL;
- /* Find the POSIX `:' separator if there is one. */
- separator = strchr (spec, ':');
+ /* Set U and G to nonzero length strings corresponding to user and
+ group specifiers or to NULL. If U is not NULL, it is a newly
+ allocated string. */
- /* If there is no colon, then see if there's a `.'. */
+ u = NULL;
if (separator == NULL)
{
- dot = strchr (spec, '.');
- /* If there's no colon but there is a `.', then first look up the
- whole spec, in case it's an OWNER name that includes a dot.
- If that fails, then we'll try again, but interpreting the `.'
- as a separator. This is a compatible extension to POSIX, since
- the POSIX-required behavior is always tried first. */
+ if (*spec)
+ u = xstrdup (spec);
+ }
+ else
+ {
+ size_t ulen = separator - spec;
+ if (ulen != 0)
+ {
+ u = xclone (spec, ulen + 1);
+ u[ulen] = '\0';
+ }
}
-
- retry:
-
- /* Replace separator with a NUL. */
- if (separator != NULL)
- *separator = '\0';
-
- /* Set U and G to non-zero length strings corresponding to user and
- group specifiers or to NULL. */
- u = (*spec == '\0' ? NULL : spec);
g = (separator == NULL || *(separator + 1) == '\0'
? NULL
: separator + 1);
- if (u == NULL && g == NULL)
- return _(E_cannot_omit_both);
-
#ifdef __DJGPP__
/* Pretend that we are the user U whose group is G. This makes
pwd and grp functions ``know'' about the UID and GID of these. */
@@ -222,32 +182,25 @@ parse_user_spec (const char *spec_arg, u
error_msg = E_bad_spec;
else
{
- unsigned long int tmp_long;
- if (! (xstrtoul (u, NULL, 10, &tmp_long, "") == LONGINT_OK
- && tmp_long <= MAXUID))
- return _(E_invalid_user);
- *uid = tmp_long;
+ unsigned long int tmp;
+ if (xstrtoul (u, NULL, 10, &tmp, "") == LONGINT_OK
+ && tmp <= MAXUID)
+ unum = tmp;
+ else
+ error_msg = E_invalid_user;
}
}
else
{
- *uid = pwd->pw_uid;
+ unum = pwd->pw_uid;
if (g == NULL && separator != NULL)
{
/* A separator was given, but a group was not specified,
so get the login group. */
- *gid = pwd->pw_gid;
- grp = getgrgid (pwd->pw_gid);
- if (grp == NULL)
- {
- char buf[INT_BUFSIZE_BOUND (uintmax_t)];
- char const *num = umaxtostr (pwd->pw_gid, buf);
- V_STRDUP (groupname, num);
- }
- else
- {
- V_STRDUP (groupname, grp->gr_name);
- }
+ char buf[INT_BUFSIZE_BOUND (uintmax_t)];
+ gnum = pwd->pw_gid;
+ grp = getgrgid (gnum);
+ gname = xstrdup (grp ? grp->gr_name : umaxtostr (gnum, buf));
endgrent ();
}
}
@@ -260,38 +213,72 @@ parse_user_spec (const char *spec_arg, u
grp = getgrnam (g);
if (grp == NULL)
{
- unsigned long int tmp_long;
- if (! (xstrtoul (g, NULL, 10, &tmp_long, "") == LONGINT_OK
- && tmp_long <= MAXGID))
- return _(E_invalid_group);
- *gid = tmp_long;
+ unsigned long int tmp;
+ if (xstrtoul (g, NULL, 10, &tmp, "") == LONGINT_OK && tmp <= MAXGID)
+ gnum = tmp;
+ else
+ error_msg = E_invalid_group;
}
else
- *gid = grp->gr_gid;
+ gnum = grp->gr_gid;
endgrent (); /* Save a file descriptor. */
-
- if (error_msg == NULL)
- V_STRDUP (groupname, g);
+ gname = xstrdup (g);
}
if (error_msg == NULL)
{
- if (u != NULL)
- *username_arg = xstrdup (u);
-
- if (groupname != NULL)
- *groupname_arg = xstrdup (groupname);
+ *uid = unum;
+ *gid = gnum;
+ *username = u;
+ *groupname = gname;
+ u = NULL;
}
+ else
+ free (gname);
- if (error_msg && dot)
- {
- separator = dot;
- dot = NULL;
- error_msg = NULL;
- goto retry;
+ free (u);
+ return _(error_msg);
+}
+
+/* Extract from SPEC, which has the form "[user][:.][group]",
+ a USERNAME, UID U, GROUPNAME, and GID G.
+ Either user or group, or both, must be present.
+ If the group is omitted but the separator is given,
+ use the given user's login group.
+ If SPEC contains a `:', then use that as the separator, ignoring
+ any `.'s. If there is no `:', but there is a `.', then first look
+ up the entire SPEC as a login name. If that look-up fails, then
+ try again interpreting the `.' as a separator.
+
+ USERNAME and GROUPNAME will be in newly malloc'd memory.
+ Either one might be NULL instead, indicating that it was not
+ given and the corresponding numeric ID was left unchanged.
+
+ Return NULL if successful, a static error message string if not. */
+
+char const *
+parse_user_spec (char const *spec, uid_t *uid, gid_t *gid,
+ char **username, char **groupname)
+{
+ char const *colon = strchr (spec, ':');
+ char const *error_msg =
+ parse_with_separator (spec, colon, uid, gid, username, groupname);
+
+ if (!colon && error_msg)
+ {
+ /* If there's no colon but there is a dot, and if looking up the
+ whole spec failed (i.e., the spec is not a owner name that
+ includes a dot), then try again, but interpret the dot as a
+ separator. This is a compatible extension to POSIX, since
+ the POSIX-required behavior is always tried first. */
+
+ char const *dot = strchr (spec, '.');
+ if (dot
+ && ! parse_with_separator (spec, dot, uid, gid, username, groupname))
+ error_msg = NULL;
}
- return _(error_msg);
+ return error_msg;
}
#ifdef TEST
Index: src/chgrp.c
===================================================================
RCS file: /home/eggert/coreutils/cu/src/chgrp.c,v
retrieving revision 1.113
diff -p -u -r1.113 chgrp.c
--- src/chgrp.c 28 Jul 2004 23:36:59 -0000 1.113
+++ src/chgrp.c 19 Aug 2004 16:27:19 -0000
@@ -75,28 +75,30 @@ static struct option const long_options[
{0, 0, 0, 0}
};
-/* Set *G according to NAME. */
+/* Return the group ID of NAME, or -1 if no name was specified. */
-static void
-parse_group (const char *name, gid_t *g)
+static gid_t
+parse_group (const char *name)
{
- struct group *grp;
+ gid_t gid = -1;
- if (*name == '\0')
- error (EXIT_FAILURE, 0, _("cannot change to null group"));
-
- grp = getgrnam (name);
- if (grp == NULL)
+ if (*name)
{
- unsigned long int tmp_long;
- if (! (xstrtoul (name, NULL, 10, &tmp_long, "") == LONGINT_OK
- && tmp_long <= GID_T_MAX))
- error (EXIT_FAILURE, 0, _("invalid group %s"), quote (name));
- *g = tmp_long;
+ struct group *grp = getgrnam (name);
+ if (grp)
+ gid = grp->gr_gid;
+ else
+ {
+ unsigned long int tmp;
+ if (! (xstrtoul (name, NULL, 10, &tmp, "") == LONGINT_OK
+ && tmp <= GID_T_MAX))
+ error (EXIT_FAILURE, 0, _("invalid group %s"), quote (name));
+ gid = tmp;
+ }
+ endgrent (); /* Save a file descriptor. */
}
- else
- *g = grp->gr_gid;
- endgrent (); /* Save a file descriptor. */
+
+ return gid;
}
void
@@ -281,8 +283,9 @@ main (int argc, char **argv)
}
else
{
- chopt.group_name = argv[optind++];
- parse_group (chopt.group_name, &gid);
+ char *group_name = argv[optind++];
+ chopt.group_name = (*group_name ? group_name : NULL);
+ gid = parse_group (group_name);
}
ok = chown_files (argv + optind, bit_flags,
Index: src/chown-core.c
===================================================================
RCS file: /home/eggert/coreutils/cu/src/chown-core.c,v
retrieving revision 1.27
diff -p -u -r1.27 chown-core.c
--- src/chown-core.c 28 Jul 2004 23:37:49 -0000 1.27
+++ src/chown-core.c 19 Aug 2004 16:52:01 -0000
@@ -124,19 +124,19 @@ describe_change (const char *file, enum
switch (changed)
{
case CH_SUCCEEDED:
- fmt = (user
- ? _("changed ownership of %s to %s\n")
- : _("changed group of %s to %s\n"));
+ fmt = (user ? _("changed ownership of %s to %s\n")
+ : group ? _("changed group of %s to %s\n")
+ : _("no change to ownership of %s\n"));
break;
case CH_FAILED:
- fmt = (user
- ? _("failed to change ownership of %s to %s\n")
- : _("failed to change group of %s to %s\n"));
+ fmt = (user ? _("failed to change ownership of %s to %s\n")
+ : group ? _("failed to change group of %s to %s\n")
+ : _("failed to change ownership of %s\n"));
break;
case CH_NO_CHANGE_REQUESTED:
- fmt = (user
- ? _("ownership of %s retained as %s\n")
- : _("group of %s retained as %s\n"));
+ fmt = (user ? _("ownership of %s retained as %s\n")
+ : group ? _("group of %s retained as %s\n")
+ : _("ownership of %s retained\n"));
break;
default:
abort ();
Index: src/chown.c
===================================================================
RCS file: /home/eggert/coreutils/cu/src/chown.c,v
retrieving revision 1.118
diff -p -u -r1.118 chown.c
--- src/chown.c 28 Jul 2004 23:37:21 -0000 1.118
+++ src/chown.c 19 Aug 2004 16:39:58 -0000
@@ -92,11 +92,10 @@ usage (int status)
else
{
printf (_("\
-Usage: %s [OPTION]... OWNER[:[GROUP]] FILE...\n\
- or: %s [OPTION]... :GROUP FILE...\n\
+Usage: %s [OPTION]... [OWNER][:[GROUP]] FILE...\n\
or: %s [OPTION]... --reference=RFILE FILE...\n\
"),
- program_name, program_name, program_name);
+ program_name, program_name);
fputs (_("\
Change the owner and/or group of each FILE to OWNER and/or GROUP.\n\
With --reference, change the owner and group of each FILE to those of RFILE.\n\
@@ -146,8 +145,8 @@ one takes effect.\n\
fputs (_("\
\n\
Owner is unchanged if missing. Group is unchanged if missing, but changed\n\
-to login group if implied by a `:'. OWNER and GROUP may be numeric as well\n\
-as symbolic.\n\
+to login group if implied by a `:' following a symbolic OWNER.\n\
+OWNER and GROUP may be numeric as well as symbolic.\n\
"), stdout);
printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
}
@@ -313,8 +312,10 @@ main (int argc, char **argv)
if (e)
error (EXIT_FAILURE, 0, "%s: %s", quote (argv[optind]), e);
- /* FIXME: set it to the empty string? */
- if (chopt.user_name == NULL)
+ /* If a group is specified but no user, set the user name to the
+ empty string so that diagnostics say "ownership :GROUP"
+ rather than "group GROUP". */
+ if (!chopt.user_name && chopt.group_name)
chopt.user_name = "";
optind++;
Index: tests/chgrp/basic
===================================================================
RCS file: /home/eggert/coreutils/cu/tests/chgrp/basic,v
retrieving revision 1.18
diff -p -u -r1.18 basic
--- tests/chgrp/basic 23 Jun 2004 15:07:04 -0000 1.18
+++ tests/chgrp/basic 19 Aug 2004 16:52:46 -0000
@@ -43,6 +43,7 @@ test "$VERBOSE" = yes && set +x
chgrp -c $g1 f
chgrp -c $g2 f
chgrp -c $g2 f
+ chgrp --verbose '' f
chgrp --verbose $g1 f
chgrp --verbose $g1 f
chgrp --verbose --reference=f2 f
@@ -80,6 +81,7 @@ test "$VERBOSE" = yes && set +x
chgrp $g2 g
sleep 1
chgrp $g1 f
+ chgrp '' f
ls -c -t f g
) 2>&1 | sed "s/\([ :]\)$g1$/\1G1/;s/\([ :]\)$g2$/\1G2/" > actual
@@ -87,6 +89,7 @@ test "$VERBOSE" = yes && set +x
cat <<\EOF > expected
changed group of `f' to G1
changed group of `f' to G2
+ownership of `f' retained
changed group of `f' to G1
group of `f' retained as G1
changed group of `f' to G2
Index: tests/chown/Makefile.am
===================================================================
RCS file: /home/eggert/coreutils/cu/tests/chown/Makefile.am,v
retrieving revision 1.4
diff -p -u -r1.4 Makefile.am
--- tests/chown/Makefile.am 16 May 2004 14:10:17 -0000 1.4
+++ tests/chown/Makefile.am 18 Aug 2004 23:31:59 -0000
@@ -2,8 +2,9 @@
AUTOMAKE_OPTIONS = 1.4 gnits
TESTS = \
+ basic \
deref \
- basic
+ separator
EXTRA_DIST = $(TESTS)
TESTS_ENVIRONMENT = \
PATH="`pwd`/../../src$(PATH_SEPARATOR)$$PATH"
--- /dev/null 2003-03-18 13:55:57 -0800
+++ tests//chown/separator 2004-08-18 19:24:08 -0700
@@ -0,0 +1,55 @@
+#!/bin/sh
+# Make sure "chown USER:GROUP FILE" works, and similar tests with separators.
+
+if test "$VERBOSE" = yes; then
+ set -x
+ chown --version
+fi
+
+pwd=`pwd`
+t0=`echo "$0" |sed 's,.*/,,'`.tmp; tmp=$t0/$$
+trap 'status=$?; cd $pwd; chmod -R u+rwx $t0; rm -rf $t0 && exit $status' 0
+trap 'status=$?; (exit $status); exit $status' 1 2 13 15
+
+framework_failure=0
+
+mkdir -p $tmp || framework_failure=1
+cd $tmp || framework_failure=1
+
+id_u=`id -u` || framework_failure=1
+test -n "$id_u" || framework_failure=1
+
+id_un=`id -un` || framework_failure=1
+test -n "$id_un" || framework_failure=1
+
+id_g=`id -g` || framework_failure=1
+test -n "$id_g" || framework_failure=1
+
+id_gn=`id -gn` || framework_failure=1
+test -n "$id_gn" || framework_failure=1
+
+if test $framework_failure = 1; then
+ echo "$0: failure in testing framework" 1>&2
+ (exit 1); exit 1
+fi
+
+fail=0
+
+chown '' . || fail=1
+
+for u in $id_u $id_un ''; do
+ for g in $id_g $id_gn ''; do
+ case $u$g in
+ *.*) seps=':' ;;
+ *) seps=': .' ;;
+ esac
+ for sep in $seps; do
+ case $u$sep$g in
+ [0-9]*$sep) chown "$u$sep$g" . 2> /dev/null && fail=1 ;;
+ *) chown "$u$sep$g" . || fail=1 ;;
+ esac
+ done
+ done
+done
+
+(exit $fail); exit $fail