tests/test-posix_spawn-open2.c

   1 /* Test of posix_spawn() function with 'open' action and O_APPEND flag.
   2    Copyright (C) 2008-2020 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 <stdbool.h>
  29 #include <stdio.h>
  30 #include <string.h>
  31 #include <unistd.h>
  32 #include <sys/types.h>
  33 #include <sys/wait.h>
  34
  35 #define CHILD_PROGRAM_FILENAME "test-posix_spawn-open2"
  36 #define DATA_FILENAME "test-posix_spawn-open2-data.tmp"
  37
  38 static int
  39 parent_main (void)
  40 {
  41   FILE *fp;
  42   char *argv[3] = { CHILD_PROGRAM_FILENAME, "-child", NULL };
  43   posix_spawn_file_actions_t actions;
  44   bool actions_allocated;
  45   int err;
  46   pid_t child;
  47   int status;
  48   int exitstatus;
  49
  50   /* Create a data file with specific contents.  */
  51   fp = fopen (DATA_FILENAME, "wb");
  52   if (fp == NULL)
  53     {
  54       perror ("cannot create data file");
  55       return 1;
  56     }
  57   fwrite ("Halle ", 1, 6, fp);
  58   if (fflush (fp) || fclose (fp))
  59     {
  60       perror ("cannot prepare data file");
  61       return 1;
  62     }
  63
  64   /* Test whether posix_spawn_file_actions_addopen with O_APPEND flag causes
  65      the child to append to this file.  */
  66   actions_allocated = false;
  67   if ((err = posix_spawn_file_actions_init (&actions)) != 0
  68       || (actions_allocated = true,
  69           (err = posix_spawn_file_actions_addopen (&actions, STDOUT_FILENO, DATA_FILENAME, O_RDWR | O_APPEND, 0600)) != 0
  70           || (err = posix_spawn (&child, CHILD_PROGRAM_FILENAME, &actions, NULL, argv, environ)) != 0))
  71     {
  72       if (actions_allocated)
  73         posix_spawn_file_actions_destroy (&actions);
  74       errno = err;
  75       perror ("subprocess failed");
  76       return 1;
  77     }
  78   posix_spawn_file_actions_destroy (&actions);
  79   status = 0;
  80   while (waitpid (child, &status, 0) != child)
  81     ;
  82   if (!WIFEXITED (status))
  83     {
  84       fprintf (stderr, "subprocess terminated with unexpected wait status %d\n", status);
  85       return 1;
  86     }
  87   exitstatus = WEXITSTATUS (status);
  88   if (exitstatus != 0)
  89     {
  90       fprintf (stderr, "subprocess terminated with unexpected exit status %d\n", exitstatus);
  91       return 1;
  92     }
  93
  94   /* Check the contents of the data file.  */
  95   fp = fopen (DATA_FILENAME, "rb");
  96   if (fp == NULL)
  97     {
  98       perror ("cannot open data file");
  99       return 1;
 100     }
 101   char buf[1024];
 102   int nread = fread (buf, 1, sizeof (buf), fp);
 103   if (!(nread == 11 && memcmp (buf, "Halle Potta", 11) == 0))
 104     {
 105       fprintf (stderr, "data file wrong: has %d bytes, expected %d bytes\n", nread, 11);
 106       return 1;
 107     }
 108   if (fclose (fp))
 109     {
 110       perror ("cannot close data file");
 111       return 1;
 112     }
 113
 114   /* Clean up data file.  */
 115   unlink (DATA_FILENAME);
 116
 117   return 0;
 118 }
 119
 120 static int
 121 child_main (void)
 122 {
 123   /* Write to STDOUT_FILENO.  */
 124   fwrite ("Potta", 1, 5, stdout);
 125   /* No 'fflush (stdout);' is needed.  It is implicit when the child process
 126      exits.  */
 127
 128   return 0;
 129 }
 130
 131 static void
 132 cleanup_then_die (int sig)
 133 {
 134   /* Clean up data file.  */
 135   unlink (DATA_FILENAME);
 136
 137   /* Re-raise the signal and die from it.  */
 138   signal (sig, SIG_DFL);
 139   raise (sig);
 140 }
 141
 142 int
 143 main (int argc, char *argv[])
 144 {
 145   int exitstatus;
 146
 147   if (!(argc > 1 && strcmp (argv[1], "-child") == 0))
 148     {
 149       /* This is the parent process.  */
 150       signal (SIGINT, cleanup_then_die);
 151       signal (SIGTERM, cleanup_then_die);
 152       #ifdef SIGHUP
 153       signal (SIGHUP, cleanup_then_die);
 154       #endif
 155
 156       exitstatus = parent_main ();
 157     }
 158   else
 159     {
 160       /* This is the child process.  */
 161       exitstatus = child_main ();
 162     }
 163   return exitstatus;
 164 }