Use vfork, by vodz

1 files changed, 22 insertions, 42 deletions

diff --git a/libbb/run_parts.c b/libbb/run_parts.c
index bf906a399..8399a6afb 100644
--- a/libbb/run_parts.c
+++ b/libbb/run_parts.c
@@ -1,53 +1,20 @@
 /* vi: set sw=4 ts=4: */
 /*
- * Mini run-parts implementation for busybox
+ * run command from specified directory
  *
  *
  * Copyright (C) 2001 by Emanuele Aina <emanuele.aina@tiscali.it>
- *
- * Based on the Debian run-parts program, version 1.15
- *   Copyright (C) 1996 Jeff Noxon <jeff@router.patch.net>,
- *   Copyright (C) 1996-1999 Guy Maor <maor@debian.org>
- *   
+ * rewrite to vfork usage by
+ * Copyright (C) 2002 by Vladimir Oleynik <dzo@simtreas.ru>
  *
  * 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 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, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
- * 02111-1307 USA
  *
  */
 
-/* This is my first attempt to write a program in C (well, this is my first
- * attempt to write a program! :-) . */
-
-/* This piece of code is heavily based on the original version of run-parts,
- * taken from debian-utils. I've only removed the long options and a the 
- * report mode. As the original run-parts support only long options, I've
- * broken compatibility because the BusyBox policy doesn't allow them. 
- * The supported options are: 
- * -t			test. Print the name of the files to be executed, without
- * 				execute them.
- * -a ARG		argument. Pass ARG as an argument the program executed. It can 
- * 				be repeated to pass multiple arguments.
- * -u MASK 		umask. Set the umask of the program executed to MASK. */
-
-/* TODO 
- * done - convert calls to error in perror... and remove error()
- * done - convert malloc/realloc to their x... counterparts 
- * done - remove catch_sigchld
- * done - use bb's concat_path_file() 
- * done - declare run_parts_main() as extern and any other function as static?
- */
 
 #include <sys/types.h>
 #include <sys/wait.h>
@@ -55,6 +22,7 @@
 #include <dirent.h>
 #include <unistd.h>
 #include <ctype.h>
+#include <errno.h>
 
 #include "libbb.h"
 
@@ -86,6 +54,11 @@ extern int run_parts(char **args, const unsigned char test_mode)
 	int i;
 	int exitstatus = 0;
 
+#if __GNUC__
+	/* Avoid longjmp clobbering */
+	(void) &i;
+	(void) &exitstatus;
+#endif
 	/* scandir() isn't POSIX, but it makes things easy. */
 	entries = scandir(args[0], &namelist, valid_name, alphasort);
 
@@ -104,23 +77,30 @@ extern int run_parts(char **args, const unsigned char test_mode)
 			if (test_mode)
 				printf("run-parts would run %s\n", filename);
 			else {
+				/* exec_errno is common vfork variable */
+				volatile int exec_errno = 0;
 				int result;
 				int pid;
 
-				if ((pid = fork()) < 0) {
+				if ((pid = vfork()) < 0) {
 					perror_msg_and_die("failed to fork");
 				} else if (!pid) {
-					execv(args[0], args);
-					perror_msg_and_die("failed to exec %s", args[0]);
+					args[0] = filename;
+					execv(filename, args);
+					exec_errno = errno;
+					_exit(1);
 				}
 
 				waitpid(pid, &result, 0);
-
+				if(exec_errno) {
+					errno = exec_errno;
+					perror_msg_and_die("failed to exec %s", filename);
+				}
 				if (WIFEXITED(result) && WEXITSTATUS(result)) {
-					perror_msg("%s exited with return code %d", args[0], WEXITSTATUS(result));
+					perror_msg("%s exited with return code %d", filename, WEXITSTATUS(result));
 					exitstatus = 1;
 				} else if (WIFSIGNALED(result)) {
-					perror_msg("%s exited because of uncaught signal %d", args[0], WTERMSIG(result));
+					perror_msg("%s exited because of uncaught signal %d", filename, WTERMSIG(result));
 					exitstatus = 1;
 				}
 			}