posix/tst-posix_spawn-setsid.c

   1 /* Test posix_spawn setsid attribute.
   2    Copyright (C) 2017-2023 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <fcntl.h>
  21 #include <spawn.h>
  22 #include <stdbool.h>
  23 #include <stdio.h>
  24 #include <sys/resource.h>
  25 #include <unistd.h>
  26
  27 #include <support/check.h>
  28
  29 static void
  30 do_test_setsid (bool test_setsid)
  31 {
  32   pid_t sid, child_sid;
  33   int res;
  34
  35   /* Current session ID.  */
  36   sid = getsid(0);
  37   if (sid == (pid_t) -1)
  38     FAIL_EXIT1 ("getsid (0): %m");
  39
  40   posix_spawnattr_t attrp;
  41   /* posix_spawnattr_init should not fail (it basically memset the
  42      attribute).  */
  43   posix_spawnattr_init (&attrp);
  44   if (test_setsid)
  45     {
  46       res = posix_spawnattr_setflags (&attrp, POSIX_SPAWN_SETSID);
  47       if (res != 0)
  48         {
  49           errno = res;
  50           FAIL_EXIT1 ("posix_spawnattr_setflags: %m");
  51         }
  52     }
  53
  54   /* Program to run.  */
  55   char *args[2] = { (char *) "true", NULL };
  56   pid_t child;
  57
  58   res = posix_spawnp (&child, "true", NULL, &attrp, args, environ);
  59   /* posix_spawnattr_destroy is noop.  */
  60   posix_spawnattr_destroy (&attrp);
  61
  62   if (res != 0)
  63     {
  64       errno = res;
  65       FAIL_EXIT1 ("posix_spawnp: %m");
  66     }
  67
  68   /* Child should have a different session ID than parent.  */
  69   child_sid = getsid (child);
  70
  71   if (child_sid == (pid_t) -1)
  72     FAIL_EXIT1 ("getsid (%i): %m", child);
  73
  74   if (test_setsid)
  75     {
  76       if (child_sid == sid)
  77         FAIL_EXIT1 ("child session ID matched parent one");
  78     }
  79   else
  80     {
  81       if (child_sid != sid)
  82         FAIL_EXIT1 ("child session ID did not match parent one");
  83     }
  84 }
  85
  86 static int
  87 do_test (void)
  88 {
  89   do_test_setsid (false);
  90   do_test_setsid (true);
  91
  92   return 0;
  93 }
  94
  95 #include <support/test-driver.c>