/* idcache.c -- map user and group IDs, cached for speed
- Copyright (C) 1985, 1988, 1989, 1990, 1997, 1998, 2003, 2005 Free
- Software Foundation, Inc.
+ Copyright (C) 1985, 1988, 1989, 1990, 1997, 1998, 2003, 2005, 2006
+ 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
along with this program; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
-#ifdef HAVE_CONFIG_H
-# include <config.h>
-#endif
+#include <config.h>
+#include <stddef.h>
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <pwd.h>
#include <grp.h>
-#if HAVE_UNISTD_H
-# include <unistd.h>
-#endif
+#include <unistd.h>
#include "xalloc.h"
uid_t u;
gid_t g;
} id;
- char *name;
struct userid *next;
+ char name[FLEXIBLE_ARRAY_MEMBER];
};
static struct userid *user_alist;
-/* 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;
/* Translate UID to a login name, with cache, or NULL if unresolved. */
char *
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 = xmalloc (sizeof *tail);
- 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;
}
/* Translate USER to a UID, with cache.
uid_t *
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__
}
#endif
- tail = xmalloc (sizeof *tail);
- 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;
}
/* 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 GID to a group name, with cache, or NULL if unresolved. */
char *
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 = xmalloc (sizeof *tail);
- 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;
}
/* Translate GROUP to a GID, with cache.
gid_t *
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 any arbitrary group name. */
+ grp functions know about an arbitrary group name. */
if (!grent && strspn (group, digits) < strlen (group))
{
setenv ("GROUP", group, 1);
}
#endif
- tail = xmalloc (sizeof *tail);
- 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;
}
projects / gnulib.git / blobdiff