tests/test-posix_spawn-fchdir.c

   1 /* Test of posix_spawn() function with 'fchdir' action.
   2    Copyright (C) 2008-2021 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Bruno Haible <bruno@clisp.org>, 2018.  */
  18
  19 #include <config.h>
  20
  21 #include <spawn.h>
  22
  23 #include <errno.h>
  24 #include <fcntl.h>
  25 #include <signal.h>
  26 #include <stdbool.h>
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include <unistd.h>
  31 #include <sys/types.h>
  32 #include <sys/wait.h>
  33
  34 #include "findprog.h"
  35
  36 static int
  37 fd_safer (int fd)
  38 {
  39   if (0 <= fd && fd <= 2)
  40     {
  41       int f = fd_safer (dup (fd));
  42       int e = errno;
  43       close (fd);
  44       errno = e;
  45       fd = f;
  46     }
  47
  48   return fd;
  49 }
  50
  51 static void
  52 test (const char *pwd_prog)
  53 {
  54   char *argv[2] = { (char *) "pwd", NULL };
  55   int rootfd;
  56   int ifd[2];
  57   sigset_t blocked_signals;
  58   sigset_t fatal_signal_set;
  59   posix_spawn_file_actions_t actions;
  60   bool actions_allocated;
  61   posix_spawnattr_t attrs;
  62   bool attrs_allocated;
  63   int err;
  64   pid_t child;
  65   int fd;
  66   FILE *fp;
  67   char line[80];
  68   int status;
  69   int exitstatus;
  70
  71   rootfd = open ("/", O_RDONLY);
  72   if (rootfd < 0)
  73     {
  74       perror ("cannot open directory");
  75       exit (1);
  76     }
  77   if (pipe (ifd) < 0 || (ifd[0] = fd_safer (ifd[0])) < 0)
  78     {
  79       perror ("cannot create pipe");
  80       exit (1);
  81     }
  82   sigprocmask (SIG_SETMASK, NULL, &blocked_signals);
  83   sigemptyset (&fatal_signal_set);
  84   sigaddset (&fatal_signal_set, SIGINT);
  85   sigaddset (&fatal_signal_set, SIGTERM);
  86   #ifdef SIGHUP
  87   sigaddset (&fatal_signal_set, SIGHUP);
  88   #endif
  89   #ifdef SIGPIPE
  90   sigaddset (&fatal_signal_set, SIGPIPE);
  91   #endif
  92   sigprocmask (SIG_BLOCK, &fatal_signal_set, NULL);
  93   actions_allocated = false;
  94   attrs_allocated = false;
  95   if ((err = posix_spawn_file_actions_init (&actions)) != 0
  96       || (actions_allocated = true,
  97           (err = posix_spawn_file_actions_adddup2 (&actions, ifd[1], STDOUT_FILENO)) != 0
  98           || (err = posix_spawn_file_actions_addclose (&actions, ifd[1])) != 0
  99           || (err = posix_spawn_file_actions_addclose (&actions, ifd[0])) != 0
 100           || (err = posix_spawn_file_actions_addopen (&actions, STDIN_FILENO, "/dev/null", O_RDONLY, 0)) != 0
 101           || (err = posix_spawn_file_actions_addfchdir (&actions, rootfd)) != 0
 102           || (err = posix_spawnattr_init (&attrs)) != 0
 103           || (attrs_allocated = true,
 104               #if defined _WIN32 && !defined __CYGWIN__
 105               0
 106               #else
 107               (err = posix_spawnattr_setsigmask (&attrs, &blocked_signals)) != 0
 108               || (err = posix_spawnattr_setflags (&attrs, POSIX_SPAWN_SETSIGMASK)) != 0
 109               #endif
 110              )
 111           || (err = posix_spawnp (&child, pwd_prog, &actions, &attrs, argv, environ)) != 0))
 112     {
 113       if (actions_allocated)
 114         posix_spawn_file_actions_destroy (&actions);
 115       if (attrs_allocated)
 116         posix_spawnattr_destroy (&attrs);
 117       sigprocmask (SIG_UNBLOCK, &fatal_signal_set, NULL);
 118       errno = err;
 119       perror ("subprocess failed");
 120       exit (1);
 121     }
 122   posix_spawn_file_actions_destroy (&actions);
 123   posix_spawnattr_destroy (&attrs);
 124   sigprocmask (SIG_UNBLOCK, &fatal_signal_set, NULL);
 125   close (ifd[1]);
 126   fd = ifd[0];
 127   fp = fdopen (fd, "r");
 128   if (fp == NULL)
 129     {
 130       fprintf (stderr, "fdopen() failed\n");
 131       exit (1);
 132     }
 133   if (fread (line, 1, 80, fp) < 2)
 134     {
 135       fprintf (stderr, "could not read expected output\n");
 136       exit (1);
 137     }
 138   if (memcmp (line, "/\n", 2) != 0)
 139     {
 140       fprintf (stderr, "read output is not the expected output\n");
 141       exit (1);
 142     }
 143   fclose (fp);
 144   status = 0;
 145   while (waitpid (child, &status, 0) != child)
 146     ;
 147   if (!WIFEXITED (status))
 148     {
 149       fprintf (stderr, "subprocess terminated with unexpected wait status %d\n", status);
 150       exit (1);
 151     }
 152   exitstatus = WEXITSTATUS (status);
 153   if (exitstatus != 0)
 154     {
 155       fprintf (stderr, "subprocess terminated with unexpected exit status %d\n", exitstatus);
 156       exit (1);
 157     }
 158 }
 159
 160 int
 161 main ()
 162 {
 163   test ("pwd");
 164
 165   /* Verify that if a program is given as a relative file name with at least one
 166      slash, it is interpreted w.r.t. the current directory after fchdir has been
 167      executed.  */
 168   {
 169     const char *abs_pwd_prog = find_in_path ("pwd");
 170
 171     if (abs_pwd_prog != NULL
 172         && abs_pwd_prog[0] == '/'
 173         && abs_pwd_prog[1] != '0' && abs_pwd_prog[1] != '/')
 174       test (&abs_pwd_prog[1]);
 175   }
 176
 177   return 0;
 178 }