/* idcache.c -- map user and group IDs, cached for speed
- Copyright (C) 1985, 1988, 1989, 1990, 1997 Free Software Foundation, Inc.
- This program is free software; you can redistribute it and/or modify
+ Copyright (C) 1985, 1988-1990, 1997-1998, 2003, 2005-2007, 2009-2014 Free
+ Software Foundation, Inc.
+
+ 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/>. */
-#if HAVE_CONFIG_H
-# include <config.h>
-#endif
+#include <config.h>
+#include "idcache.h"
+#include <stddef.h>
#include <stdio.h>
-#include <sys/types.h>
+#include <string.h>
#include <pwd.h>
#include <grp.h>
-#if defined(STDC_HEADERS) || defined(HAVE_STRING_H)
-# include <string.h>
-#else
-# include <strings.h>
-#endif
+#include <unistd.h>
-#if HAVE_UNISTD_H
-# include <unistd.h>
-#endif
+#include "xalloc.h"
-#ifndef _POSIX_VERSION
-struct passwd *getpwuid ();
-struct passwd *getpwnam ();
-struct group *getgrgid ();
-struct group *getgrnam ();
+#ifdef __DJGPP__
+static char digits[] = "0123456789";
#endif
-char *xmalloc ();
-char *xstrdup ();
-
struct userid
{
union
uid_t u;
gid_t g;
} id;
- char *name;
struct userid *next;
+ char name[FLEXIBLE_ARRAY_MEMBER];
};
+/* FIXME: provide a function to free any malloc'd storage and reset lists,
+ so that an application can use code like this just before exiting:
+ #ifdef lint
+ idcache_clear ();
+ #endif
+*/
+
static struct userid *user_alist;
-#ifdef NOT_USED
-/* The members of this list have names not in the local passwd file. */
+/* Each entry on list is a user name for which the first lookup failed. */
static struct userid *nouser_alist;
-#endif /* NOT_USED */
-/* Translate UID to a login name, with cache.
- If UID cannot be resolved, return NULL.
- Cache lookup failures, too. */
+/* Use the same struct as for userids. */
+static struct userid *group_alist;
+
+/* Each entry on list is a group name for which the first lookup failed. */
+static struct userid *nogroup_alist;
+
+/* Translate UID to a login name, with cache, or NULL if unresolved. */
char *
-getuser (uid)
- uid_t uid;
+getuser (uid_t uid)
{
- register struct userid *tail;
- struct passwd *pwent;
+ struct userid *tail;
+ struct userid *match = NULL;
for (tail = user_alist; tail; tail = tail->next)
- if (tail->id.u == uid)
- return tail->name;
+ {
+ if (tail->id.u == uid)
+ {
+ match = tail;
+ break;
+ }
+ }
- pwent = getpwuid (uid);
- tail = (struct userid *) xmalloc (sizeof (struct userid));
- tail->id.u = uid;
- tail->name = (pwent ? xstrdup (pwent->pw_name) : NULL);
+ if (match == NULL)
+ {
+ struct passwd *pwent = getpwuid (uid);
+ char const *name = pwent ? pwent->pw_name : "";
+ match = xmalloc (offsetof (struct userid, name) + strlen (name) + 1);
+ match->id.u = uid;
+ strcpy (match->name, name);
+
+ /* Add to the head of the list, so most recently used is first. */
+ match->next = user_alist;
+ user_alist = match;
+ }
- /* Add to the head of the list, so most recently used is first. */
- tail->next = user_alist;
- user_alist = tail;
- return tail->name;
+ return match->name[0] ? match->name : NULL;
}
-#ifdef NOT_USED
-
/* Translate USER to a UID, with cache.
Return NULL if there is no such user.
(We also cache which user names have no passwd entry,
so we don't keep looking them up.) */
uid_t *
-getuidbyname (user)
- const char *user;
+getuidbyname (const char *user)
{
- register struct userid *tail;
+ struct userid *tail;
struct passwd *pwent;
for (tail = user_alist; tail; tail = tail->next)
for (tail = nouser_alist; tail; tail = tail->next)
/* Avoid a function call for the most common case. */
if (*tail->name == *user && !strcmp (tail->name, user))
- return 0;
+ return NULL;
pwent = getpwnam (user);
+#ifdef __DJGPP__
+ /* We need to pretend to be the user USER, to make
+ pwd functions know about an arbitrary user name. */
+ if (!pwent && strspn (user, digits) < strlen (user))
+ {
+ setenv ("USER", user, 1);
+ pwent = getpwnam (user); /* now it will succeed */
+ }
+#endif
- tail = (struct userid *) xmalloc (sizeof (struct userid));
- tail->name = xstrdup (user);
+ tail = xmalloc (offsetof (struct userid, name) + strlen (user) + 1);
+ strcpy (tail->name, user);
/* Add to the head of the list, so most recently used is first. */
if (pwent)
tail->next = nouser_alist;
nouser_alist = tail;
- return 0;
+ return NULL;
}
-#endif /* NOT_USED */
-
-/* Use the same struct as for userids. */
-static struct userid *group_alist;
-#ifdef NOT_USED
-static struct userid *nogroup_alist;
-#endif
-
-/* Translate GID to a group name or a stringified number,
- with cache. */
+/* Translate GID to a group name, with cache, or NULL if unresolved. */
char *
-getgroup (gid)
- gid_t gid;
+getgroup (gid_t gid)
{
- register struct userid *tail;
- struct group *grent;
+ struct userid *tail;
+ struct userid *match = NULL;
for (tail = group_alist; tail; tail = tail->next)
- if (tail->id.g == gid)
- return tail->name;
+ {
+ if (tail->id.g == gid)
+ {
+ match = tail;
+ break;
+ }
+ }
- grent = getgrgid (gid);
- tail = (struct userid *) xmalloc (sizeof (struct userid));
- tail->id.g = gid;
- tail->name = (grent ? xstrdup (grent->gr_name) : NULL);
+ if (match == NULL)
+ {
+ struct group *grent = getgrgid (gid);
+ char const *name = grent ? grent->gr_name : "";
+ match = xmalloc (offsetof (struct userid, name) + strlen (name) + 1);
+ match->id.g = gid;
+ strcpy (match->name, name);
+
+ /* Add to the head of the list, so most recently used is first. */
+ match->next = group_alist;
+ group_alist = match;
+ }
- /* Add to the head of the list, so most recently used is first. */
- tail->next = group_alist;
- group_alist = tail;
- return tail->name;
+ return match->name[0] ? match->name : NULL;
}
-#ifdef NOT_USED
-
/* Translate GROUP to a GID, with cache.
Return NULL if there is no such group.
(We also cache which group names have no group entry,
so we don't keep looking them up.) */
gid_t *
-getgidbyname (group)
- const char *group;
+getgidbyname (const char *group)
{
- register struct userid *tail;
+ struct userid *tail;
struct group *grent;
for (tail = group_alist; tail; tail = tail->next)
for (tail = nogroup_alist; tail; tail = tail->next)
/* Avoid a function call for the most common case. */
if (*tail->name == *group && !strcmp (tail->name, group))
- return 0;
+ return NULL;
grent = getgrnam (group);
+#ifdef __DJGPP__
+ /* We need to pretend to belong to group GROUP, to make
+ grp functions know about an arbitrary group name. */
+ if (!grent && strspn (group, digits) < strlen (group))
+ {
+ setenv ("GROUP", group, 1);
+ grent = getgrnam (group); /* now it will succeed */
+ }
+#endif
- tail = (struct userid *) xmalloc (sizeof (struct userid));
- tail->name = xstrdup (group);
+ tail = xmalloc (offsetof (struct userid, name) + strlen (group) + 1);
+ strcpy (tail->name, group);
/* Add to the head of the list, so most recently used is first. */
if (grent)
tail->next = nogroup_alist;
nogroup_alist = tail;
- return 0;
+ return NULL;
}
-
-#endif /* NOT_USED */
projects / gnulib.git / blobdiff