[patch] sysvinit-exec.patch

sysvinit-exec.patch (text/plain), 4.64 KB, created by i.Dark_Templar on 2014-10-03 20:16:12 UTC

diff --git a/sysvinit-2.88dsf/src/init.c b/sysvinit-2.88dsf/src/init.c
index 27532ad..4124f6a 100644
--- a/sysvinit-2.88dsf/src/init.c
+++ b/sysvinit-2.88dsf/src/init.c
@@ -168,6 +168,7 @@ struct actions {
   { "initdefault", INITDEFAULT	},
   { "sysinit",	   SYSINIT	},
   { "kbrequest",   KBREQUEST    },
+  { "exec",   EXEC    },
   { NULL,	   0		},
 };
 
@@ -924,7 +925,7 @@ void init_freeenv(char **e)
  *
  */
 static
-pid_t spawn(CHILD *ch, int *res)
+pid_t spawn(CHILD *ch, int *res, int do_fork)
 {
   char *args[16];		/* Argv array */
   char buf[136];		/* Line buffer */
@@ -933,7 +934,7 @@ pid_t spawn(CHILD *ch, int *res)
   time_t t;			/* System time */
   int oldAlarm;			/* Previous alarm value */
   char *proc = ch->process;	/* Command line */
-  pid_t pid, pgrp;		/* child, console process group. */
+  pid_t pid = -1, pgrp;		/* child, console process group. */
   sigset_t nmask, omask;	/* For blocking SIGCHLD */
   struct sigaction sa;
 
@@ -1033,25 +1034,29 @@ pid_t spawn(CHILD *ch, int *res)
 	/*
 	 *	Block sigchild while forking.
 	 */
-	sigemptyset(&nmask);
-	sigaddset(&nmask, SIGCHLD);
-	sigprocmask(SIG_BLOCK, &nmask, &omask);
+	if (do_fork) {
+		sigemptyset(&nmask);
+		sigaddset(&nmask, SIGCHLD);
+		sigprocmask(SIG_BLOCK, &nmask, &omask);
+	}
 
-	if ((pid = fork()) == 0) {
+	if ((!do_fork) || ((pid = fork()) == 0)) {
 
-		close(0);
-		close(1);
-		close(2);
-		if (pipe_fd >= 0) close(pipe_fd);
+		if (do_fork) {
+			close(0);
+			close(1);
+			close(2);
+			if (pipe_fd >= 0) close(pipe_fd);
 
-  		sigprocmask(SIG_SETMASK, &omask, NULL);
+			sigprocmask(SIG_SETMASK, &omask, NULL);
+		}
 
 		/*
 		 *	In sysinit, boot, bootwait or single user mode:
 		 *	for any wait-type subprocess we _force_ the console
 		 *	to be its controlling tty.
 		 */
-  		if (strchr("*#sS", runlevel) && ch->flags & WAITING) {
+  		if (strchr("*#sS", runlevel) && ch->flags & WAITING && do_fork) {
 			/*
 			 *	We fork once extra. This is so that we can
 			 *	wait and change the process group and session
@@ -1123,8 +1128,10 @@ pid_t spawn(CHILD *ch, int *res)
 			/* Set ioctl settings to default ones */
 			console_stty();
 
-  		} else {
-			setsid();
+		} else {
+			if (do_fork) {
+				setsid();
+			}
 			if ((f = console_open(O_RDWR|O_NOCTTY)) < 0) {
 				initlog(L_VB, "open(%s): %s", console_dev,
 					strerror(errno));
@@ -1150,8 +1157,10 @@ pid_t spawn(CHILD *ch, int *res)
 		 * FIXME: that's for compatibility with *very*
 		 * old getties - probably it can be taken out.
 		 */
-		if (ch->process[0] != '+')
-			write_utmp_wtmp("", ch->id, getpid(), INIT_PROCESS, "");
+		if (do_fork) {
+			if (ch->process[0] != '+')
+				write_utmp_wtmp("", ch->id, getpid(), INIT_PROCESS, "");
+		}
 
   		/* Reset all the signals, set up environment */
   		for(f = 1; f < NSIG; f++) SETSIG(sa, f, SIG_DFL, SA_RESTART);
@@ -1173,16 +1182,31 @@ pid_t spawn(CHILD *ch, int *res)
 		}
   		initlog(L_VB, "cannot execute \"%s\"", args[1]);
 
-		if (ch->process[0] != '+')
-			write_utmp_wtmp("", ch->id, getpid(), DEAD_PROCESS, NULL);
-  		exit(1);
+		if (do_fork) {
+			if (ch->process[0] != '+')
+				write_utmp_wtmp("", ch->id, getpid(), DEAD_PROCESS, NULL);
+			exit(1);
+		}
+		else
+		{
+			/*
+			 * exec() failed, continue init process
+			 * Make sure there are some fallback records after an exec record
+			 */
+
+			initlog(L_VB, "cannot execute \"%s\", continuing to next action", args[1]);
+		 }
   	}
+
 	*res = pid;
-  	sigprocmask(SIG_SETMASK, &omask, NULL);
 
-	INITDBG(L_VB, "Started id %s (pid %d)", ch->id, pid);
+	if (do_fork) {
+		sigprocmask(SIG_SETMASK, &omask, NULL);
 
-	if (pid == -1) {
+		INITDBG(L_VB, "Started id %s (pid %d)", ch->id, pid);
+	}
+
+	if (do_fork && (pid == -1)) {
 		initlog(L_VB, "cannot fork, retry..");
 		do_sleep(5);
 		continue;
@@ -1220,8 +1244,11 @@ void startup(CHILD *ch)
 		case ONDEMAND:
 		case RESPAWN:
   			ch->flags |= RUNNING;
-  			(void)spawn(ch, &(ch->pid));
+  			(void)spawn(ch, &(ch->pid), 1);
   			break;
+  		case EXEC:
+			(void)spawn(ch, &(ch->pid), 0);
+			break;
 	}
 }
 
@@ -2606,7 +2633,7 @@ void init_main(void)
 	if (emerg_shell) {
 		pid_t rc;
 		SETSIG(sa, SIGCHLD, SIG_DFL, SA_RESTART);
-		if (spawn(&ch_emerg, &f) > 0) {
+		if (spawn(&ch_emerg, &f, 1) > 0) {
 			while((rc = wait(&st)) != f)
 				if (rc < 0 && errno == ECHILD)
 					break;
diff --git a/src/init.h b/src/init.h
index 9763140..17a3f0d 100644
--- a/sysvinit-2.88dsf/src/init.h
+++ b/sysvinit-2.88dsf/src/init.h
@@ -78,6 +78,7 @@ void wall(const char *text, int remote);
 #define SYSINIT		       13
 #define POWERFAILNOW           14
 #define KBREQUEST               15
+#define EXEC               16
 
 /* Information about a process in the in-core inittab */
 typedef struct _child_ {