libc/sysdeps/linux/common/setegid.c

   1 /*
   2  * Copyright (C) 2000-2006 Erik Andersen <andersen@uclibc.org>
   3  *
   4  * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
   5  */
   6
   7 #include <unistd.h>
   8 #include <stdio.h>
   9 #include <errno.h>
  10 #include <grp.h>
  11 #include <sys/types.h>
  12 #include <sys/syscall.h>
  13
  14
  15 #if !defined __UCLIBC_LINUX_SPECIFIC__
  16 #undef __NR_setresgid
  17 #undef __NR_setresgid32
  18 #endif
  19
  20 int setegid(gid_t gid)
  21 {
  22     int result;
  23
  24     if (gid == (gid_t) ~0)
  25     {
  26         __set_errno (EINVAL);
  27         return -1;
  28     }
  29
  30 #if (defined __NR_setresgid || defined __NR_setresgid32) && defined __USE_GNU
  31     result = setresgid(-1, gid, -1);
  32     if (result == -1 && errno == ENOSYS)
  33         /* Will also set the saved group ID if egid != gid,
  34          * making it impossible to switch back...*/
  35 #endif
  36         result = setregid(-1, gid);
  37
  38     return result;
  39 }