Initial import

[samba] / source / lib / util_pw.c

diff --git a/source/lib/util_pw.c b/source/lib/util_pw.c
new file mode 100644 (file)
index 0000000..13349ba
--- /dev/null
+++ b/source/lib/util_pw.c
@@ -0,0 +1,146 @@
+/* 
+   Unix SMB/CIFS implementation.
+
+   Safe versions of getpw* calls
+
+   Copyright (C) Andrew Bartlett 2002
+   
+   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 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
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   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., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include "includes.h"
+
+static struct passwd *alloc_copy_passwd(const struct passwd *from) 
+{
+       struct passwd *ret = SMB_XMALLOC_P(struct passwd);
+       ZERO_STRUCTP(ret);
+       ret->pw_name = smb_xstrdup(from->pw_name);
+       ret->pw_passwd = smb_xstrdup(from->pw_passwd);
+       ret->pw_uid = from->pw_uid;
+       ret->pw_gid = from->pw_gid;
+       ret->pw_gecos = smb_xstrdup(from->pw_gecos);
+       ret->pw_dir = smb_xstrdup(from->pw_dir);
+       ret->pw_shell = smb_xstrdup(from->pw_shell);
+       return ret;
+}
+
+void passwd_free (struct passwd **buf)
+{
+       if (!*buf) {
+               DEBUG(0, ("attempted double-free of allocated passwd\n"));
+               return;
+       }
+
+       SAFE_FREE((*buf)->pw_name);
+       SAFE_FREE((*buf)->pw_passwd);
+       SAFE_FREE((*buf)->pw_gecos);
+       SAFE_FREE((*buf)->pw_dir);
+       SAFE_FREE((*buf)->pw_shell);
+
+       SAFE_FREE(*buf);
+}
+
+#define PWNAMCACHE_SIZE 4
+static struct passwd *pwnam_cache[PWNAMCACHE_SIZE];
+static BOOL pwnam_cache_initialized = False;
+
+static void init_pwnam_cache(void)
+{
+       int i;
+
+       if (pwnam_cache_initialized)
+               return;
+
+       for (i=0; i<PWNAMCACHE_SIZE; i++)
+               pwnam_cache[i] = NULL;
+
+       pwnam_cache_initialized = True;
+       return;
+}
+
+void flush_pwnam_cache(void)
+{
+       int i;
+
+       init_pwnam_cache();
+
+       for (i=0; i<PWNAMCACHE_SIZE; i++) {
+               if (pwnam_cache[i] == NULL)
+                       continue;
+
+               passwd_free(&pwnam_cache[i]);
+       }
+}
+
+struct passwd *getpwnam_alloc(const char *name) 
+{
+       int i;
+
+       struct passwd *temp;
+
+       init_pwnam_cache();
+
+       for (i=0; i<PWNAMCACHE_SIZE; i++) {
+               if ((pwnam_cache[i] != NULL) && 
+                   (strcmp(name, pwnam_cache[i]->pw_name) == 0)) {
+                       DEBUG(10, ("Got %s from pwnam_cache\n", name));
+                       return alloc_copy_passwd(pwnam_cache[i]);
+               }
+       }
+
+       temp = sys_getpwnam(name);
+       
+       if (!temp) {
+#if 0
+               if (errno == ENOMEM) {
+                       /* what now? */
+               }
+#endif
+               return NULL;
+       }
+
+       for (i=0; i<PWNAMCACHE_SIZE; i++) {
+               if (pwnam_cache[i] == NULL)
+                       break;
+       }
+
+       if (i == PWNAMCACHE_SIZE)
+               i = rand() % PWNAMCACHE_SIZE;
+
+       if (pwnam_cache[i] != NULL)
+               passwd_free(&pwnam_cache[i]);
+
+       pwnam_cache[i] = alloc_copy_passwd(temp);
+
+       return alloc_copy_passwd(temp);
+}
+
+struct passwd *getpwuid_alloc(uid_t uid) 
+{
+       struct passwd *temp;
+
+       temp = sys_getpwuid(uid);
+       
+       if (!temp) {
+#if 0
+               if (errno == ENOMEM) {
+                       /* what now? */
+               }
+#endif
+               return NULL;
+       }
+
+       return alloc_copy_passwd(temp);
+}