/* getugroups.c -- return a list of the groups a user is in
- Copyright (C) 1990, 1991, 1998 Free Software Foundation.
+
+ Copyright (C) 1990, 1991, 1998, 1999, 2000, 2003, 2004 Free
+ Software Foundation.
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
# include <unistd.h>
#endif
+#include <errno.h>
+#ifndef EOVERFLOW
+# define EOVERFLOW EINVAL
+#endif
+
/* setgrent, getgrent, and endgrent are not specified by POSIX.1,
so header files might not declare them.
If you don't have them at all, we can't implement this function.
You lose! */
struct group *getgrent ();
-#if defined(STDC_HEADERS) || defined(HAVE_STRING_H)
-# include <string.h>
-#else
-# include <strings.h>
-#endif
+#include <string.h>
+
+#define STREQ(s1, s2) ((strcmp (s1, s2) == 0))
-/* Like `getgroups', but for user USERNAME instead of for
- the current process. */
+/* Like `getgroups', but for user USERNAME instead of for the current
+ process. Store at most MAXCOUNT group IDs in the GROUPLIST array.
+ If GID is not -1, store it first (if possible). GID should be the
+ group ID (pw_gid) obtained from getpwuid, in case USERNAME is not
+ listed in /etc/groups.
+ Always return the number of groups of which USERNAME is a member. */
int
-getugroups (int maxcount, GETGROUPS_T *grouplist, char *username)
+getugroups (int maxcount, GETGROUPS_T *grouplist, char *username, gid_t gid)
{
struct group *grp;
register char **cp;
register int count = 0;
+ if (gid != (gid_t) -1)
+ {
+ if (maxcount != 0)
+ grouplist[count] = gid;
+ ++count;
+ }
+
setgrent ();
while ((grp = getgrent ()) != 0)
- for (cp = grp->gr_mem; *cp; ++cp)
- if (!strcmp (username, *cp))
+ {
+ for (cp = grp->gr_mem; *cp; ++cp)
{
int n;
+ if ( ! STREQ (username, *cp))
+ continue;
+
/* See if this group number is already on the list. */
for (n = 0; n < count; ++n)
- if (grouplist[n] == grp->gr_gid)
+ if (grouplist && grouplist[n] == grp->gr_gid)
break;
/* If it's a new group number, then try to add it to the list. */
grouplist[count] = grp->gr_gid;
}
count++;
+ if (count < 0)
+ {
+ errno = EOVERFLOW;
+ return -1;
+ }
}
}
+ }
endgrent ();
+
return count;
}