Get vfork_daemon_rexec working under uclinux

include/libbb.h

@@ -473,7 +473,8 @@ extern llist_t *llist_add_to(llist_t *old_head, char *new_item);
 extern void print_login_issue(const char *issue_file, const char *tty);
 extern void print_login_prompt(void);
 
-extern void vfork_daemon_rexec(int argc, char **argv, char *foreground_opt);
+extern void vfork_daemon_rexec(int nochdir, int noclose,
+		int argc, char **argv, char *foreground_opt);
 extern void get_terminal_width_height(int fd, int *width, int *height);
 extern unsigned long get_ug_id(const char *s, long (*my_getxxnam)(const char *));
 extern void xregcomp(regex_t *preg, const char *regex, int cflags);

libbb/vfork_daemon_rexec.c

@@ -1,27 +1,78 @@
 /*
  * Rexec program for system have fork() as vfork() with foregound option
- * Copyright (C) Vladminr Oleynik and many different people.
+ *
+ * Copyright (C) Vladimir N. Oleynik <dzo@simtreas.ru>
+ * Copyright (C) 2003 Russ Dill <Russ.Dill@asu.edu>
+ *
+ * daemon() portion taken from uclibc:
+ *
+ * Copyright (c) 1991, 1993
+ *      The Regents of the University of California.  All rights reserved.
+ *
+ * Modified for uClibc by Erik Andersen <andersee@debian.org>
+ *
+ * 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
  */
 
 #include <unistd.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <paths.h>
 #include "libbb.h"
 
 
 #if defined(__uClinux__)
-void vfork_daemon_rexec(int argc, char **argv, char *foreground_opt)
+void vfork_daemon_rexec(int nochdir, int noclose,
+		int argc, char **argv, char *foreground_opt)
 {
+	int fd;
 	char **vfork_args;
 	int a = 0;
 	
+	setsid();
+	
+	if (!nochdir)
+		chdir("/");
+
+	if (!noclose && (fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) {
+		dup2(fd, STDIN_FILENO);
+		dup2(fd, STDOUT_FILENO);
+		dup2(fd, STDERR_FILENO);
+		if (fd > 2)
+			close(fd);
+	}
+
 	vfork_args = xcalloc(sizeof(char *), argc + 3);
+	vfork_args[a++] = "/bin/busybox";
 	while(*argv) {
 	    vfork_args[a++] = *argv;
 	    argv++;
 	}
 	vfork_args[a] = foreground_opt;
-	execvp("/proc/self/exe", vfork_args);
-	vfork_args[0] = "/bin/busybox";
+	switch (vfork()) {
+	case 0: /* child */
+		/* Make certain we are not a session leader, or else we
+		 * might reacquire a controlling terminal */
+		if (vfork())
+			_exit(0);
 		execv(vfork_args[0], vfork_args);
 		bb_perror_msg_and_die("execv %s", vfork_args[0]);
+	case -1: /* error */
+		bb_perror_msg_and_die("vfork");
+	default: /* parent */
+		exit(0);
+	}	
 }
 #endif /* uClinux */

miscutils/crond.c

@@ -200,14 +200,12 @@ crond_main(int ac, char **av)
      */
 
     if (!(opt & 4)) {
+#if defined(__uClinux__)
+	/* reexec for vfork() do continue parent */
+	vfork_daemon_rexec(1, 0, ac, av, "-f");
+#else /* uClinux */
 	if(daemon(1, 0) < 0) {
 		bb_perror_msg_and_die("daemon");
-	} 
-#if defined(__uClinux__)
-	else {
-	    /* reexec for vfork() do continue parent */
-	    vfork_daemon_rexec(ac, av, "-f");
-	}
 #endif /* uClinux */
     }
 

sysklogd/klogd.c

@@ -147,11 +147,12 @@ extern int klogd_main(int argc, char **argv)
 	}
 
 	if (doFork) {
+#if defined(__uClinux__)
+		vfork_daemon_rexec(0, 1, argc, argv, "-n");
+#else /* __uClinux__ */
 		if (daemon(0, 1) < 0)
 			bb_perror_msg_and_die("daemon");
-#if defined(__uClinux__)
-		vfork_daemon_rexec(argc, argv, "-n");
-#endif
+#endif /* __uClinux__ */
 	}
 	doKlogd(console_log_level);
 

sysklogd/syslogd.c

@@ -681,11 +681,12 @@ extern int syslogd_main(int argc, char **argv)
 	umask(0);
 
 	if (doFork == TRUE) {
+#if defined(__uClinux__)
+		vfork_daemon_rexec(0, 1, argc, argv, "-n");
+#else /* __uClinux__ */
 		if(daemon(0, 1) < 0)
 			bb_perror_msg_and_die("daemon");
-#if defined(__uClinux__)
-		vfork_daemon_rexec(argc, argv, "-n");
-#endif
+#endif /* __uClinux__ */
 	}
 	doSyslogd();