diff options
Diffstat (limited to 'lib/execute.c')
| -rw-r--r-- | lib/execute.c | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/lib/execute.c b/lib/execute.c new file mode 100644 index 0000000..48cba72 --- /dev/null +++ b/lib/execute.c @@ -0,0 +1,179 @@ +/* Creation of autonomous subprocesses. + Copyright (C) 2001 Free Software Foundation, Inc. + Written by Bruno Haible <haible@clisp.cons.org>, 2001. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software Foundation, + Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + + +#ifdef HAVE_CONFIG_H +# include "config.h" +#endif + +/* Specification. */ +#include "execute.h" + +#include <errno.h> +#include <fcntl.h> +#include <stdbool.h> +#include <stdlib.h> + +#ifdef HAVE_UNISTD_H +# include <unistd.h> +#endif + +#ifdef HAVE_POSIX_SPAWN +# include <spawn.h> +#else +# ifdef HAVE_VFORK_H +# include <vfork.h> +# endif +#endif + +#include "error.h" +#include "wait-process.h" +#include "libgettext.h" + +#ifndef STDIN_FILENO +# define STDIN_FILENO 0 +#endif +#ifndef STDOUT_FILENO +# define STDOUT_FILENO 1 +#endif +#ifndef STDERR_FILENO +# define STDERR_FILENO 2 +#endif + +#define _(str) gettext (str) + + +/* Prototypes for local functions. Needed to ensure compiler checking of + function argument counts despite of K&R C function definition syntax. */ +#ifdef EINTR +static inline int nonintr_close PARAMS ((int fd)); +static inline int nonintr_open PARAMS ((const char *pathname, int oflag, + mode_t mode)); +#endif + + +#ifdef EINTR + +/* EINTR handling for close(), open(). + These functions can return -1/EINTR even though we don't have any + signal handlers set up, namely when we get interrupted via SIGSTOP. */ + +static inline int +nonintr_close (fd) + int fd; +{ + int retval; + + do + retval = close (fd); + while (retval < 0 && errno == EINTR); + + return retval; +} +#define close nonintr_close + +static inline int +nonintr_open (pathname, oflag, mode) + const char *pathname; + int oflag; + mode_t mode; +{ + int retval; + + do + retval = open (pathname, oflag, mode); + while (retval < 0 && errno == EINTR); + + return retval; +} +#define open nonintr_open + +#endif + + +/* Execute a command, optionally redirecting any of the three standard file + descriptors to /dev/null. Exit if it didn't terminate correctly. + Otherwise return its exit code. */ +int +execute (progname, prog_path, prog_argv, null_stdin, null_stdout, null_stderr) + const char *progname; + const char *prog_path; + char **prog_argv; + bool null_stdin; + bool null_stdout; + bool null_stderr; +{ +#if HAVE_POSIX_SPAWN + posix_spawn_file_actions_t actions; + int err; + pid_t child; +#else + int child; +#endif + +#if HAVE_POSIX_SPAWN + if ((err = posix_spawn_file_actions_init (&actions)) != 0 + || (null_stdin + && (err = posix_spawn_file_actions_addopen (&actions, STDIN_FILENO, + "/dev/null", O_RDONLY, 0)) + != 0) + || (null_stdout + && (err = posix_spawn_file_actions_addopen (&actions, STDOUT_FILENO, + "/dev/null", O_RDWR, 0)) + != 0) + || (null_stderr + && (err = posix_spawn_file_actions_addopen (&actions, STDERR_FILENO, + "/dev/null", O_RDWR, 0)) + != 0) + || (err = posix_spawnp (&child, prog_path, &actions, NULL, prog_argv, + environ)) != 0) + error (EXIT_FAILURE, err, _("%s subprocess failed"), progname); + posix_spawn_file_actions_destroy (&actions); +#else + /* Use vfork() instead of fork() for efficiency. */ + if ((child = vfork ()) == 0) + { + /* Child process code. */ + int nullinfd; + int nulloutfd; + + if ((!null_stdin + || ((nullinfd = open ("/dev/null", O_RDONLY, 0)) >= 0 + && (nullinfd == STDIN_FILENO + || (dup2 (nullinfd, STDIN_FILENO) >= 0 + && close (nullinfd) >= 0)))) + && (!(null_stdout || null_stderr) + || ((nulloutfd = open ("/dev/null", O_RDWR, 0)) >= 0 + && (!null_stdout + || nulloutfd == STDOUT_FILENO + || dup2 (nulloutfd, STDOUT_FILENO) >= 0) + && (!null_stderr + || nulloutfd == STDERR_FILENO + || dup2 (nulloutfd, STDERR_FILENO) >= 0) + && ((null_stdout && nulloutfd == STDOUT_FILENO) + || (null_stderr && nulloutfd == STDERR_FILENO) + || close (nulloutfd) >= 0)))) + execvp (prog_path, prog_argv); + _exit (-1); + } + if (child == -1) + error (EXIT_FAILURE, errno, _("%s subprocess failed"), progname); +#endif + + return wait_subprocess (child, progname); +} |