From: Todd C. Miller <Todd.Miller@courtesan.com>
Date: Wed, 16 Mar 2011 16:02:04 +0000 (-0400)
Subject: Save the controlling tty process group before suspending so we can
X-Git-Tag: SUDO_1_8_1~91^2
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=240642399b352f8eb0129b95a8d0a4df1cd6c62c;p=sudo

Save the controlling tty process group before suspending so we can
restore it when we resume.  Fixes job control problems on Linux
caused by the previous attemp to fix resuming a shell when I/O
logging not enabled.
---

diff --git a/src/exec.c b/src/exec.c
index 2cda3c9e8..510ce1134 100644
--- a/src/exec.c
+++ b/src/exec.c
@@ -444,9 +444,21 @@ handle_signals(int fd, pid_t child, int log_io, struct command_status *cstat)
 		/* If not logging I/O and child has exited we are done. */
 		if (!log_io) {
 		    if (WIFSTOPPED(status)) {
-			/* Child may not have privs to suspend us itself. */
+			/*
+			 * Save the controlling terminal's process group
+			 * so we can restore it after we resume.
+			 */
+			pid_t saved_pgrp = (pid_t)-1;
+			int fd = open(_PATH_TTY, O_RDWR|O_NOCTTY, 0);
+			if (fd != -1)
+			    saved_pgrp = tcgetpgrp(fd);
 			if (kill(getpid(), WSTOPSIG(status)) != 0)
 			    warning("kill(%d, %d)", getpid(), WSTOPSIG(status));
+			if (fd != -1) {
+			    if (saved_pgrp != (pid_t)-1)
+				(void)tcsetpgrp(fd, saved_pgrp);
+			    close(fd);
+			}
 		    } else {
 			/* Child has exited, we are done. */
 			cstat->type = CMD_WSTATUS;
@@ -462,24 +474,10 @@ handle_signals(int fd, pid_t child, int log_io, struct command_status *cstat)
 		schedule_signal(signo);
 	    } else {
 		/* Nothing listening on sv[0], send directly. */
-		if (signo == SIGALRM) {
+		if (signo == SIGALRM)
 		    terminate_child(child, FALSE);
-		} else {
-		    if (signo == SIGCONT) {
-			/*
-			 * Before continuing the child, make it the foreground
-			 * pgrp if possible.  Fixes resuming a shell.
-			 */
-			int fd = open(_PATH_TTY, O_RDWR|O_NOCTTY, 0);
-			if (fd != -1) {
-			    if (tcgetpgrp(fd) == getpgrp())
-				(void)tcsetpgrp(fd, child);
-			    close(fd);
-			}
-		    }
-		    if (kill(child, signo) != 0)
-			warning("kill(%d, %d)", child, signo);
-		}
+		else if (kill(child, signo) != 0)
+		    warning("kill(%d, %d)", child, signo);
 	    }
 	}
     }