Imported Upstream version 1.4.16upstream/1.4.16

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
+}