This patch fixes a problem that smbd process for LPQ thread
is orphaned if the parent smbd is aborted.

See also: https://bugzilla.samba.org/show_bug.cgi?id=5688

-- fumiyas, 2008-12-09

diff -rup samba-3.2.4/source/printing/printing.c samba-3.2.4.osstech/source/printing/printing.c
--- samba-3.2.4/source/printing/printing.c	2008-09-18 15:49:02.000000000 +0900
+++ samba-3.2.4.osstech/source/printing/printing.c	2008-12-09 18:53:14.000000000 +0900
@@ -1394,7 +1394,23 @@ main thread of the background lpq update
 ****************************************************************************/
 void start_background_queue(void)
 {
+	static int pause_pipe[2] = {-1, -1};
+
 	DEBUG(3,("start_background_queue: Starting background LPQ thread\n"));
+
+	if (pause_pipe[0] >= 0) {
+		close(pause_pipe[0]);
+		pause_pipe[0] = -1;
+	}
+	if (pause_pipe[1] >= 0) {
+		close(pause_pipe[1]);
+		pause_pipe[1] = -1;
+	}
+	if (pipe(pause_pipe) == -1) {
+		DEBUG(5,("start_background_queue: cannot create pipe. %s\n", strerror(errno) ));
+		exit(1);
+	}
+
 	background_lpq_updater_pid = sys_fork();
 
 	if (background_lpq_updater_pid == -1) {
@@ -1406,6 +1422,9 @@ void start_background_queue(void)
 		/* Child. */
 		DEBUG(5,("start_background_queue: background LPQ thread started\n"));
 
+		close(pause_pipe[0]);
+		pause_pipe[0] = -1;
+
 		if (!reinit_after_fork(smbd_messaging_context(), true)) {
 			DEBUG(0,("reinit_after_fork() failed\n"));
 			smb_panic("reinit_after_fork() failed");
@@ -1423,7 +1442,17 @@ void start_background_queue(void)
 		
 		DEBUG(5,("start_background_queue: background LPQ thread waiting for messages\n"));
 		while (1) {
-			pause();
+			fd_set pause_fds;
+			int pause_select;
+
+			FD_ZERO(&pause_fds);
+			FD_SET(pause_pipe[1], &pause_fds);
+			pause_select = sys_select(pause_pipe[1]+1, &pause_fds, NULL, NULL, NULL);
+			/* pause_pipe[0] is closed, i.e. parent smbd and
+			   children are aborted. */
+			if (pause_select == 1) {
+                                exit_server_cleanly(NULL);
+			}
 			
 			/* check for some essential signals first */
 			
@@ -1449,6 +1478,9 @@ void start_background_queue(void)
 						   0);
 		}
 	}
+
+	close(pause_pipe[1]);
+	pause_pipe[1] = -1;
 }
 
 /****************************************************************************
samba-3.2.4.osstech/source/printingだけに発見: printing.c.old