/* userspec.c -- Parse a user and group string.
- Copyright (C) 1989-1992, 1997-1998, 2000, 2002-2004 Free Software
+ Copyright (C) 1989-1992, 1997-1998, 2000, 2002-2014 Free Software
Foundation, Inc.
- This program is free software; you can redistribute it and/or modify
+ This program 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 2, or (at your option)
- any later version.
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software Foundation,
- Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
/* Written by David MacKenzie <djm@gnu.ai.mit.edu>. */
-#if HAVE_CONFIG_H
-# include <config.h>
-#endif
-
-#include <alloca.h>
+#include <config.h>
/* Specification. */
#include "userspec.h"
+#include <stdbool.h>
#include <stdio.h>
#include <sys/types.h>
#include <pwd.h>
#include <stdlib.h>
#include <string.h>
-#if HAVE_UNISTD_H
-# include <unistd.h>
-#endif
+#include <unistd.h>
-#include "strdup.h"
-#include "posixver.h"
+#include "intprops.h"
+#include "inttostr.h"
#include "xalloc.h"
#include "xstrtol.h"
#define _(msgid) gettext (msgid)
#define N_(msgid) msgid
-#ifndef _POSIX_VERSION
-struct passwd *getpwnam ();
-struct group *getgrnam ();
-struct group *getgrgid ();
-#endif
-
#ifndef HAVE_ENDGRENT
# define endgrent() ((void) 0)
#endif
# define endpwent() ((void) 0)
#endif
-/* The extra casts work around common compiler bugs. */
-#define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
-/* The outer cast is needed to work around a bug in Cray C 5.0.3.0.
- It is necessary at least when t == time_t. */
-#define TYPE_MINIMUM(t) ((t) (TYPE_SIGNED (t) \
- ? ~ (t) 0 << (sizeof (t) * CHAR_BIT - 1) : (t) 0))
-#define TYPE_MAXIMUM(t) ((t) (~ (t) 0 - TYPE_MINIMUM (t)))
-
#ifndef UID_T_MAX
# define UID_T_MAX TYPE_MAXIMUM (uid_t)
#endif
# 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 \
- { \
- int _len = strlen ((src)); \
- (dest) = (char *) alloca (_len + 1); \
- strcpy (dest, src); \
- } \
- while (0)
+#ifdef __DJGPP__
/* 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.
+ - Its arg may be any int or unsigned int; it need not be an unsigned char
+ or EOF.
- It's typically faster.
POSIX says that only '0' through '9' are digits. Prefer ISDIGIT to
- ISDIGIT_LOCALE unless it's important to use the locale's definition
- of `digit' even when the host does not conform to POSIX. */
-#define ISDIGIT(c) ((unsigned) (c) - '0' <= 9)
+ isdigit unless it's important to use the locale's definition
+ of "digit" even when the host does not conform to POSIX. */
+# define ISDIGIT(c) ((unsigned int) (c) - '0' <= 9)
-/* Return nonzero if STR represents an unsigned decimal integer,
- otherwise return 0. */
+/* Return true if STR represents an unsigned decimal integer. */
-static int
+static bool
is_number (const char *str)
{
- for (; *str; str++)
- if (!ISDIGIT (*str))
- return 0;
- return 1;
-}
-
-/* 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.
+ do
+ {
+ if (!ISDIGIT (*str))
+ return false;
+ }
+ while (*++str);
- Return NULL if successful, a static error message string if not. */
+ return true;
+}
+#endif
-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");
+ static const char *E_bad_spec = N_("invalid spec");
const char *error_msg;
- char *spec; /* A copy we can write on. */
struct passwd *pwd;
struct group *grp;
- char *g, *u, *separator;
- char *groupname;
- int maybe_retry = 0;
- char *dot = NULL;
+ char *u;
+ char const *g;
+ char *gname = NULL;
+ uid_t unum = *uid;
+ gid_t gnum = gid ? *gid : -1;
error_msg = NULL;
- *username_arg = *groupname_arg = NULL;
- groupname = NULL;
-
- V_STRDUP (spec, spec_arg);
+ if (username)
+ *username = NULL;
+ if (groupname)
+ *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 `.'. */
- if (separator == NULL && posix2_version () < 200112)
+ 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. */
- /* FIXME: accepting `.' as the separator is contrary to POSIX.
- someday we should drop support for this. */
- if (dot)
- maybe_retry = 1;
+ if (*spec)
+ u = xstrdup (spec);
+ }
+ else
+ {
+ size_t ulen = separator - spec;
+ if (ulen != 0)
+ {
+ u = xmemdup (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. */
+ pwd and grp functions "know" about the UID and GID of these. */
if (u && !is_number (u))
setenv ("USER", u, 1);
if (g && !is_number (g))
if (u != NULL)
{
- pwd = getpwnam (u);
+ /* If it starts with "+", skip the look-up. */
+ pwd = (*u == '+' ? NULL : getpwnam (u));
if (pwd == NULL)
- {
-
- if (!is_number (u))
- error_msg = E_invalid_user;
- else
- {
- int use_login_group;
- use_login_group = (separator != NULL && g == NULL);
- if (use_login_group)
- error_msg = E_bad_spec;
- else
- {
- unsigned long int tmp_long;
- if (xstrtoul (u, NULL, 0, &tmp_long, NULL) != LONGINT_OK
- || tmp_long > MAXUID)
- return _(E_invalid_user);
- *uid = tmp_long;
- }
- }
- }
+ {
+ bool use_login_group = (separator != NULL && g == NULL);
+ if (use_login_group)
+ {
+ /* If there is no group,
+ then there may not be a trailing ":", either. */
+ error_msg = E_bad_spec;
+ }
+ else
+ {
+ unsigned long int tmp;
+ if (xstrtoul (u, NULL, 10, &tmp, "") == LONGINT_OK
+ && tmp <= MAXUID && (uid_t) tmp != (uid_t) -1)
+ unum = tmp;
+ else
+ error_msg = E_invalid_user;
+ }
+ }
else
- {
- *uid = 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)
- {
- /* This is enough room to hold the unsigned decimal
- representation of any 32-bit quantity and the trailing
- zero byte. */
- char uint_buf[21];
- sprintf (uint_buf, "%u", (unsigned) (pwd->pw_gid));
- V_STRDUP (groupname, uint_buf);
- }
- else
- {
- V_STRDUP (groupname, grp->gr_name);
- }
- endgrent ();
- }
- }
+ {
+ unum = pwd->pw_uid;
+ if (g == NULL && separator != NULL)
+ {
+ /* A separator was given, but a group was not specified,
+ so get the login group. */
+ char buf[INT_BUFSIZE_BOUND (uintmax_t)];
+ gnum = pwd->pw_gid;
+ grp = getgrgid (gnum);
+ gname = xstrdup (grp ? grp->gr_name : umaxtostr (gnum, buf));
+ endgrent ();
+ }
+ }
endpwent ();
}
if (g != NULL && error_msg == NULL)
{
/* Explicit group. */
- grp = getgrnam (g);
+ /* If it starts with "+", skip the look-up. */
+ grp = (*g == '+' ? NULL : getgrnam (g));
if (grp == NULL)
- {
- if (!is_number (g))
- error_msg = E_invalid_group;
- else
- {
- unsigned long int tmp_long;
- if (xstrtoul (g, NULL, 0, &tmp_long, NULL) != 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 && (gid_t) tmp != (gid_t) -1)
+ gnum = tmp;
+ else
+ error_msg = E_invalid_group;
+ }
else
- *gid = grp->gr_gid;
- endgrent (); /* Save a file descriptor. */
-
- if (error_msg == NULL)
- V_STRDUP (groupname, g);
+ gnum = grp->gr_gid;
+ endgrent (); /* Save a file descriptor. */
+ gname = xstrdup (g);
}
if (error_msg == NULL)
{
- if (u != NULL)
- {
- *username_arg = strdup (u);
- if (*username_arg == NULL)
- error_msg = xalloc_msg_memory_exhausted;
- }
-
- if (groupname != NULL && error_msg == NULL)
- {
- *groupname_arg = strdup (groupname);
- if (*groupname_arg == NULL)
- {
- if (*username_arg != NULL)
- {
- free (*username_arg);
- *username_arg = NULL;
- }
- error_msg = xalloc_msg_memory_exhausted;
- }
- }
+ *uid = unum;
+ if (gid)
+ *gid = gnum;
+ if (username)
+ {
+ *username = u;
+ u = NULL;
+ }
+ if (groupname)
+ {
+ *groupname = gname;
+ gname = NULL;
+ }
}
- if (error_msg && maybe_retry)
+ free (u);
+ free (gname);
+ return _(error_msg);
+}
+
+/* Extract from SPEC, which has the form "[user][:.][group]",
+ a USERNAME, UID U, GROUPNAME, and GID G.
+ If the GID parameter is NULL the entire SPEC is treated as a user.
+ If the USERNAME and GROUPNAME parameters are NULL they're ignored.
+ 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 = gid ? strchr (spec, ':') : NULL;
+ char const *error_msg =
+ parse_with_separator (spec, colon, uid, gid, username, groupname);
+
+ if (gid && !colon && error_msg)
{
- maybe_retry = 0;
- separator = dot;
- error_msg = NULL;
- goto retry;
+ /* If there's no colon but there is a dot, and if looking up the
+ whole spec failed (i.e., the spec is not an 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
tmp = strdup (argv[i]);
e = parse_user_spec (tmp, &uid, &gid, &username, &groupname);
free (tmp);
- printf ("%s: %u %u %s %s %s\n",
- argv[i],
- (unsigned int) uid,
- (unsigned int) gid,
- NULL_CHECK (username),
- NULL_CHECK (groupname),
- NULL_CHECK (e));
+ printf ("%s: %lu %lu %s %s %s\n",
+ argv[i],
+ (unsigned long int) uid,
+ (unsigned long int) gid,
+ NULL_CHECK (username),
+ NULL_CHECK (groupname),
+ NULL_CHECK (e));
}
exit (0);
}
#endif
+
+/*
+Local Variables:
+indent-tabs-mode: nil
+End:
+*/
projects / gnulib.git / blobdiff