summaryrefslogtreecommitdiff
path: root/lib/execute.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/execute.c')
-rw-r--r--lib/execute.c278
1 files changed, 278 insertions, 0 deletions
diff --git a/lib/execute.c b/lib/execute.c
new file mode 100644
index 0000000..fe57e22
--- /dev/null
+++ b/lib/execute.c
@@ -0,0 +1,278 @@
+/* Creation of autonomous subprocesses.
+ Copyright (C) 2001-2004, 2006-2011 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 3 of the License, 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, see <http://www.gnu.org/licenses/>. */
+
+
+#include <config.h>
+
+/* Specification. */
+#include "execute.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <unistd.h>
+
+#include "error.h"
+#include "fatal-signal.h"
+#include "wait-process.h"
+#include "gettext.h"
+
+#define _(str) gettext (str)
+
+#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+
+/* Native Woe32 API. */
+# include <process.h>
+# include "w32spawn.h"
+
+#else
+
+/* Unix API. */
+# include <spawn.h>
+
+#endif
+
+/* The results of open() in this file are not used with fchdir,
+ therefore save some unnecessary work in fchdir.c. */
+#undef open
+#undef close
+
+
+#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 (int fd)
+{
+ int retval;
+
+ do
+ retval = close (fd);
+ while (retval < 0 && errno == EINTR);
+
+ return retval;
+}
+#define close nonintr_close
+
+static inline int
+nonintr_open (const char *pathname, int oflag, mode_t mode)
+{
+ int retval;
+
+ do
+ retval = open (pathname, oflag, mode);
+ while (retval < 0 && errno == EINTR);
+
+ return retval;
+}
+#undef open /* avoid warning on VMS */
+#define open nonintr_open
+
+#endif
+
+
+/* Execute a command, optionally redirecting any of the three standard file
+ descriptors to /dev/null. Return its exit code.
+ If it didn't terminate correctly, exit if exit_on_error is true, otherwise
+ return 127.
+ If slave_process is true, the child process will be terminated when its
+ creator receives a catchable fatal signal. */
+int
+execute (const char *progname,
+ const char *prog_path, char **prog_argv,
+ bool ignore_sigpipe,
+ bool null_stdin, bool null_stdout, bool null_stderr,
+ bool slave_process, bool exit_on_error,
+ int *termsigp)
+{
+#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+
+ /* Native Woe32 API. */
+ int orig_stdin;
+ int orig_stdout;
+ int orig_stderr;
+ int exitcode;
+ int nullinfd;
+ int nulloutfd;
+
+ /* FIXME: Need to free memory allocated by prepare_spawn. */
+ prog_argv = prepare_spawn (prog_argv);
+
+ /* Save standard file handles of parent process. */
+ if (null_stdin)
+ orig_stdin = dup_safer_noinherit (STDIN_FILENO);
+ if (null_stdout)
+ orig_stdout = dup_safer_noinherit (STDOUT_FILENO);
+ if (null_stderr)
+ orig_stderr = dup_safer_noinherit (STDERR_FILENO);
+ exitcode = -1;
+
+ /* Create standard file handles of child process. */
+ nullinfd = -1;
+ nulloutfd = -1;
+ if ((!null_stdin
+ || ((nullinfd = open ("NUL", O_RDONLY, 0)) >= 0
+ && (nullinfd == STDIN_FILENO
+ || (dup2 (nullinfd, STDIN_FILENO) >= 0
+ && close (nullinfd) >= 0))))
+ && (!(null_stdout || null_stderr)
+ || ((nulloutfd = open ("NUL", 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))))
+ /* Use spawnvpe and pass the environment explicitly. This is needed if
+ the program has modified the environment using putenv() or [un]setenv().
+ On Windows, programs have two environments, one in the "environment
+ block" of the process and managed through SetEnvironmentVariable(), and
+ one inside the process, in the location retrieved by the 'environ'
+ macro. When using spawnvp() without 'e', the child process inherits a
+ copy of the environment block - ignoring the effects of putenv() and
+ [un]setenv(). */
+ {
+ exitcode = spawnvpe (P_WAIT, prog_path, (const char **) prog_argv,
+ (const char **) environ);
+ if (exitcode < 0 && errno == ENOEXEC)
+ {
+ /* prog is not an native executable. Try to execute it as a
+ shell script. Note that prepare_spawn() has already prepended
+ a hidden element "sh.exe" to prog_argv. */
+ --prog_argv;
+ exitcode = spawnvpe (P_WAIT, prog_argv[0], (const char **) prog_argv,
+ (const char **) environ);
+ }
+ }
+ if (nulloutfd >= 0)
+ close (nulloutfd);
+ if (nullinfd >= 0)
+ close (nullinfd);
+
+ /* Restore standard file handles of parent process. */
+ if (null_stderr)
+ undup_safer_noinherit (orig_stderr, STDERR_FILENO);
+ if (null_stdout)
+ undup_safer_noinherit (orig_stdout, STDOUT_FILENO);
+ if (null_stdin)
+ undup_safer_noinherit (orig_stdin, STDIN_FILENO);
+
+ if (termsigp != NULL)
+ *termsigp = 0;
+
+ if (exitcode == -1)
+ {
+ if (exit_on_error || !null_stderr)
+ error (exit_on_error ? EXIT_FAILURE : 0, errno,
+ _("%s subprocess failed"), progname);
+ return 127;
+ }
+
+ return exitcode;
+
+#else
+
+ /* Unix API. */
+ /* Note about 127: Some errors during posix_spawnp() cause the function
+ posix_spawnp() to return an error code; some other errors cause the
+ subprocess to exit with return code 127. It is implementation
+ dependent which error is reported which way. We treat both cases as
+ equivalent. */
+ sigset_t blocked_signals;
+ posix_spawn_file_actions_t actions;
+ bool actions_allocated;
+ posix_spawnattr_t attrs;
+ bool attrs_allocated;
+ int err;
+ pid_t child;
+
+ if (slave_process)
+ {
+ sigprocmask (SIG_SETMASK, NULL, &blocked_signals);
+ block_fatal_signals ();
+ }
+ actions_allocated = false;
+ attrs_allocated = false;
+ if ((err = posix_spawn_file_actions_init (&actions)) != 0
+ || (actions_allocated = true,
+ (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)
+ || (slave_process
+ && ((err = posix_spawnattr_init (&attrs)) != 0
+ || (attrs_allocated = true,
+ (err = posix_spawnattr_setsigmask (&attrs,
+ &blocked_signals))
+ != 0
+ || (err = posix_spawnattr_setflags (&attrs,
+ POSIX_SPAWN_SETSIGMASK))
+ != 0)))
+ || (err = posix_spawnp (&child, prog_path, &actions,
+ attrs_allocated ? &attrs : NULL, prog_argv,
+ environ))
+ != 0))
+ {
+ if (actions_allocated)
+ posix_spawn_file_actions_destroy (&actions);
+ if (attrs_allocated)
+ posix_spawnattr_destroy (&attrs);
+ if (slave_process)
+ unblock_fatal_signals ();
+ if (termsigp != NULL)
+ *termsigp = 0;
+ if (exit_on_error || !null_stderr)
+ error (exit_on_error ? EXIT_FAILURE : 0, err,
+ _("%s subprocess failed"), progname);
+ return 127;
+ }
+ posix_spawn_file_actions_destroy (&actions);
+ if (attrs_allocated)
+ posix_spawnattr_destroy (&attrs);
+ if (slave_process)
+ {
+ register_slave_subprocess (child);
+ unblock_fatal_signals ();
+ }
+
+ return wait_subprocess (child, progname, ignore_sigpipe, null_stderr,
+ slave_process, exit_on_error, termsigp);
+
+#endif
+}