diff options
Diffstat (limited to 'posix/tst-spawn3.c')
| -rw-r--r-- | posix/tst-spawn3.c | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/posix/tst-spawn3.c b/posix/tst-spawn3.c new file mode 100644 index 0000000000..7d5ffc6cac --- /dev/null +++ b/posix/tst-spawn3.c @@ -0,0 +1,189 @@ +/* Check posix_spawn add file actions. + Copyright (C) 2016 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#include <stdio.h> +#include <spawn.h> +#include <error.h> +#include <errno.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <sys/wait.h> +#include <sys/resource.h> + +static int do_test (void); +#define TEST_FUNCTION do_test () +#include <test-skeleton.c> + +static int +do_test (void) +{ + /* The test checks if posix_spawn open file action close the file descriptor + before opening a new one in case the input file descriptor is already + opened. It does by exhausting all file descriptors on the process before + issue posix_spawn. It then issues a posix_spawn for '/bin/sh echo $$' + and add two rules: + + 1. Redirect stdout to a temporary filepath + 2. Redirect stderr to stdout + + If the implementation does not close the file 1. will fail with + EMFILE. */ + + struct rlimit rl; + int max_fd = 24; + + /* Set maximum number of file descriptor to a low value to avoid open + too many files in environments where RLIMIT_NOFILE is large and to + limit the array size to track the opened file descriptors. */ + + if (getrlimit (RLIMIT_NOFILE, &rl) == -1) + { + printf ("error: getrlimit RLIMIT_NOFILE failed"); + exit (EXIT_FAILURE); + } + + max_fd = (rl.rlim_cur < max_fd ? rl.rlim_cur : max_fd); + rl.rlim_cur = max_fd; + + if (setrlimit (RLIMIT_NOFILE, &rl) == 1) + { + printf ("error: setrlimit RLIMIT_NOFILE to %u failed", max_fd); + exit (EXIT_FAILURE); + } + + /* Exhauste the file descriptor limit with temporary files. */ + int files[max_fd]; + int nfiles = 0; + for (;;) + { + int fd = create_temp_file ("tst-spawn3.", NULL); + if (fd == -1) + { + if (errno != EMFILE) + { + printf ("error: create_temp_file returned -1 with " + "errno != EMFILE\n"); + exit (EXIT_FAILURE); + } + break; + } + files[nfiles++] = fd; + } + + posix_spawn_file_actions_t a; + if (posix_spawn_file_actions_init (&a) != 0) + { + puts ("error: spawn_file_actions_init failed"); + exit (EXIT_FAILURE); + } + + /* Executes a /bin/sh echo $$ 2>&1 > /tmp/tst-spawn3.pid . */ + const char pidfile[] = "/tmp/tst-spawn3.pid"; + if (posix_spawn_file_actions_addopen (&a, STDOUT_FILENO, pidfile, O_WRONLY | + O_CREAT | O_TRUNC, 0644) != 0) + { + puts ("error: spawn_file_actions_addopen failed"); + exit (EXIT_FAILURE); + } + + if (posix_spawn_file_actions_adddup2 (&a, STDOUT_FILENO, STDERR_FILENO) != 0) + { + puts ("error: spawn_file_actions_addclose"); + exit (EXIT_FAILURE); + } + + /* Since execve (called by posix_spawn) might require to open files to + actually execute the shell script, setup to close the temporary file + descriptors. */ + for (int i=0; i<nfiles; i++) + { + if (posix_spawn_file_actions_addclose (&a, files[i])) + { + printf ("error: posix_spawn_file_actions_addclose failed"); + exit (EXIT_FAILURE); + } + } + + char *spawn_argv[] = { (char *) _PATH_BSHELL, (char *) "-c", + (char *) "echo $$", NULL }; + pid_t pid; + if (posix_spawn (&pid, _PATH_BSHELL, &a, NULL, spawn_argv, NULL) != 0) + { + puts ("error: posix_spawn failed"); + exit (EXIT_FAILURE); + } + + int status; + int err = waitpid (pid, &status, 0); + if (err != pid) + { + puts ("error: waitpid failed"); + exit (EXIT_FAILURE); + } + + /* Close the temporary files descriptor so it can check posix_spawn + output. */ + for (int i=0; i<nfiles; i++) + { + if (close (files[i])) + { + printf ("error: close failed\n"); + exit (EXIT_FAILURE); + } + } + + int pidfd = open (pidfile, O_RDONLY); + if (pidfd == -1) + { + printf ("error: open pidfile failed\n"); + exit (EXIT_FAILURE); + } + + char buf[64]; + ssize_t n; + if ((n = read (pidfd, buf, sizeof (buf))) < 0) + { + printf ("error: read pidfile failed\n"); + exit (EXIT_FAILURE); + } + + unlink (pidfile); + + /* We only expect to read the PID. */ + char *endp; + long int rpid = strtol (buf, &endp, 10); + if (*endp != '\n') + { + printf ("error: didn't parse whole line: \"%s\"\n", buf); + exit (EXIT_FAILURE); + } + if (endp == buf) + { + puts ("error: read empty line"); + exit (EXIT_FAILURE); + } + + if (rpid != pid) + { + printf ("error: found \"%s\", expected PID %ld\n", buf, (long int) pid); + exit (EXIT_FAILURE); + } + + return 0; +} |