initial import

1 files changed, 145 insertions, 0 deletions

diff --git a/sysdeps/posix/system.c b/sysdeps/posix/system.c
new file mode 100644
index 0000000000..69b004bb41
--- /dev/null
+++ b/sysdeps/posix/system.c
@@ -0,0 +1,145 @@
+/* Copyright (C) 1991, 1992, 1994 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 Library General Public License as
+published by the Free Software Foundation; either version 2 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <ansidecl.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/wait.h>
+#include <signal.h>
+#include <sys/types.h>
+
+
+#ifndef	HAVE_GNU_LD
+#define	__environ	environ
+#endif
+
+#define	SHELL_PATH	"/bin/sh"	/* Path of the shell.  */
+#define	SHELL_NAME	"sh"		/* Name to give it.  */
+
+/* Execute LINE as a shell command, returning its status.  */
+int
+DEFUN(system, (line), register CONST char *line)
+{
+  int status, save;
+  pid_t pid;
+  struct sigaction sa, intr, quit;
+#ifndef WAITPID_CANNOT_BLOCK_SIGCHLD
+  sigset_t block, omask;
+#endif
+
+  if (line == NULL)
+    return 1;
+
+  sa.sa_handler = SIG_IGN;
+  sa.sa_flags = 0;
+  __sigemptyset (&sa.sa_mask);
+
+  if (__sigaction (SIGINT, &sa, &intr) < 0)
+    return -1;
+  if (__sigaction (SIGQUIT, &sa, &quit) < 0)
+    {
+      save = errno;
+      (void) __sigaction (SIGINT, &intr, (struct sigaction *) NULL);
+      errno = save;
+      return -1;
+    }
+
+#ifndef WAITPID_CANNOT_BLOCK_SIGCHLD
+
+/* SCO 3.2v4 has a bug where `waitpid' will never return if SIGCHLD is
+   blocked.  This makes it impossible for `system' to be implemented in
+   compliance with POSIX.2-1992.  They have acknowledged that this is a bug
+   but I have not seen nor heard of any forthcoming fix.  */
+
+  __sigemptyset (&block);
+  __sigaddset (&block, SIGCHLD);
+  save = errno;
+  if (__sigprocmask (SIG_BLOCK, &block, &omask) < 0)
+    {
+      if (errno == ENOSYS)
+	errno = save;
+      else
+	{
+	  save = errno;
+	  (void) __sigaction (SIGINT, &intr, (struct sigaction *) NULL);
+	  (void) __sigaction (SIGQUIT, &quit, (struct sigaction *) NULL);
+	  errno = save;
+	  return -1;
+	}
+    }
+#define UNBLOCK	__sigprocmask (SIG_SETMASK, &omask, (sigset_t *) NULL)
+#else
+#define UNBLOCK 0
+#endif
+
+  pid = __vfork ();
+  if (pid == (pid_t) 0)
+    {
+      /* Child side.  */
+      CONST char *new_argv[4];
+      new_argv[0] = SHELL_NAME;
+      new_argv[1] = "-c";
+      new_argv[2] = line;
+      new_argv[3] = NULL;
+
+      /* Restore the signals.  */
+      (void) __sigaction (SIGINT, &intr, (struct sigaction *) NULL);
+      (void) __sigaction (SIGQUIT, &quit, (struct sigaction *) NULL);
+      (void) UNBLOCK;
+
+      /* Exec the shell.  */
+      (void) __execve (SHELL_PATH, (char *CONST *) new_argv, __environ);
+      _exit (127);
+    }
+  else if (pid < (pid_t) 0)
+    /* The fork failed.  */
+    status = -1;
+  else
+    /* Parent side.  */
+#ifdef	NO_WAITPID
+    {
+      pid_t child;
+      do
+	{
+	  child = __wait (&status);
+	  if (child <= -1)
+	    {
+	      status = -1;
+	      break;
+	    }
+	} while (child != pid);
+    }
+#else
+    if (__waitpid (pid, &status, 0) != pid)
+      status = -1;
+#endif
+
+  save = errno;
+  if ((__sigaction (SIGINT, &intr, (struct sigaction *) NULL) |
+       __sigaction (SIGQUIT, &quit, (struct sigaction *) NULL) |
+       UNBLOCK) != 0)
+    {
+      if (errno == ENOSYS)
+	errno = save;
+      else
+	return -1;
+    }
+
+  return status;
+}