tests/test-posix_spawn-open2.c

   1 /* Test of posix_spawn() function with 'open' action and O_APPEND flag.
   2    Copyright (C) 2008-2024 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>, 2020.  */
  18
  19 /* Test whether posix_spawn_file_actions_addopen supports the O_APPEND flag.  */
  20
  21 #include <config.h>
  22
  23 #include <spawn.h>
  24
  25 #include <errno.h>
  26 #include <fcntl.h>
  27 #include <signal.h>
  28 #include <stdio.h>
  29 #include <string.h>
  30 #include <unistd.h>
  31 #include <sys/types.h>
  32 #include <sys/wait.h>
  33
  34 #define CHILD_PROGRAM_FILENAME "test-posix_spawn-open2" EXEEXT
  35 #define DATA_FILENAME "test-posix_spawn-open2-data.tmp"
  36
  37 static int
  38 parent_main (void)
  39 {
  40   FILE *fp;
  41   char *argv[3] = { CHILD_PROGRAM_FILENAME, "-child", NULL };
  42   posix_spawn_file_actions_t actions;
  43   bool actions_allocated;
  44   int err;
  45   pid_t child;
  46   int status;
  47   int exitstatus;
  48
  49   /* Create a data file with specific contents.  */
  50   fp = fopen (DATA_FILENAME, "wb");
  51   if (fp == NULL)
  52     {
  53       perror ("cannot create data file");
  54       return 1;
  55     }
  56   fwrite ("Halle ", 1, 6, fp);
  57   if (fflush (fp) || fclose (fp))
  58     {
  59       perror ("cannot prepare data file");
  60       return 1;
  61     }
  62
  63   /* Test whether posix_spawn_file_actions_addopen with O_APPEND flag causes
  64      the child to append to this file.  */
  65   actions_allocated = false;
  66   if ((err = posix_spawn_file_actions_init (&actions)) != 0
  67       || (actions_allocated = true,
  68           (err = posix_spawn_file_actions_addopen (&actions, STDOUT_FILENO, DATA_FILENAME, O_RDWR | O_APPEND, 0600)) != 0
  69           || (err = posix_spawn (&child, CHILD_PROGRAM_FILENAME, &actions, NULL, argv, environ)) != 0))
  70     {
  71       if (actions_allocated)
  72         posix_spawn_file_actions_destroy (&actions);
  73       errno = err;
  74       perror ("subprocess failed");
  75       return 1;
  76     }
  77   posix_spawn_file_actions_destroy (&actions);
  78   status = 0;
  79   while (waitpid (child, &status, 0) != child)
  80     ;
  81   if (!WIFEXITED (status))
  82     {
  83       fprintf (stderr, "subprocess terminated with unexpected wait status %d\n", status);
  84       return 1;
  85     }
  86   exitstatus = WEXITSTATUS (status);
  87   if (exitstatus != 0)
  88     {
  89       fprintf (stderr, "subprocess terminated with unexpected exit status %d\n", exitstatus);
  90       return 1;
  91     }
  92
  93   /* Check the contents of the data file.  */
  94   fp = fopen (DATA_FILENAME, "rb");
  95   if (fp == NULL)
  96     {
  97       perror ("cannot open data file");
  98       return 1;
  99     }
 100   char buf[1024];
 101   int nread = fread (buf, 1, sizeof (buf), fp);
 102   if (!(nread == 11 && memcmp (buf, "Halle Potta", 11) == 0))
 103     {
 104       fprintf (stderr, "data file wrong: has %d bytes, expected %d bytes\n", nread, 11);
 105       return 1;
 106     }
 107   if (fclose (fp))
 108     {
 109       perror ("cannot close data file");
 110       return 1;
 111     }
 112
 113   /* Clean up data file.  */
 114   unlink (DATA_FILENAME);
 115
 116   return 0;
 117 }
 118
 119 static int
 120 child_main (void)
 121 {
 122   /* Write to STDOUT_FILENO.  */
 123   fwrite ("Potta", 1, 5, stdout);
 124   /* No 'fflush (stdout);' is needed.  It is implicit when the child process
 125      exits.  */
 126
 127   return 0;
 128 }
 129
 130 static void
 131 cleanup_then_die (int sig)
 132 {
 133   /* Clean up data file.  */
 134   unlink (DATA_FILENAME);
 135
 136   /* Re-raise the signal and die from it.  */
 137   signal (sig, SIG_DFL);
 138   raise (sig);
 139 }
 140
 141 int
 142 main (int argc, char *argv[])
 143 {
 144   int exitstatus;
 145
 146   if (!(argc > 1 && strcmp (argv[1], "-child") == 0))
 147     {
 148       /* This is the parent process.  */
 149       signal (SIGINT, cleanup_then_die);
 150       signal (SIGTERM, cleanup_then_die);
 151       #ifdef SIGHUP
 152       signal (SIGHUP, cleanup_then_die);
 153       #endif
 154
 155       exitstatus = parent_main ();
 156     }
 157   else
 158     {
 159       /* This is the child process.  */
 160       exitstatus = child_main ();
 161     }
 162   return exitstatus;
 163 }