From 3e4485642bd79f6a047c27bc494ad69918eedcd6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marc=20Andr=C3=A9=20Tanner?= <mat@brain-dump.org>
Date: Tue, 17 Jun 2014 15:59:17 +0200
Subject: [PATCH] Do not start server main loop if execvp(3) failed

---
 abduco.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/abduco.c b/abduco.c
index bf1f45e..56fcad8 100644
--- a/abduco.c
+++ b/abduco.c
@@ -22,6 +22,7 @@
 #include <stdbool.h>
 #include <stddef.h>
 #include <signal.h>
+#include <poll.h>
 #include <libgen.h>
 #include <string.h>
 #include <limits.h>
@@ -298,6 +299,9 @@ static bool create_session(const char *name, char * const argv[]) {
 				dup2(fd, 2);
 			#endif /* NDEBUG */
 				close(pipefds[1]);
+				struct pollfd pipe_status = { .fd = pipefds[0], .events = POLLIN };
+				if (poll(&pipe_status, 1, -1) == 1 && pipe_status.revents == POLLHUP)
+					exit(EXIT_FAILURE);
 				server_mainloop();
 				break;
 			}
@@ -314,8 +318,9 @@ static bool create_session(const char *name, char * const argv[]) {
 		close(pipefds[1]);
 		int status;
 		wait(&status); /* wait for first fork */
-		if ((status = read_all(pipefds[0], errormsg, sizeof(errormsg))) > 0) {
-			write_all(STDERR_FILENO, errormsg, status);
+		ssize_t len = read_all(pipefds[0], errormsg, sizeof(errormsg));
+		if (len > 0) {
+			write_all(STDERR_FILENO, errormsg, len);
 			unlink(sockaddr.sun_path);
 			exit(EXIT_FAILURE);
 		}