From 913342415cb7d24fbfdbfe415fd729f6f35f1f1c Mon Sep 17 00:00:00 2001
From: Jun Wu <quark@zju.edu.cn>
Date: Sun, 9 Nov 2014 16:11:45 +0800
Subject: [PATCH] Check fork failed

---
 src/ljudge.cc | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/ljudge.cc b/src/ljudge.cc
index 468ca18..9e8671b 100644
--- a/src/ljudge.cc
+++ b/src/ljudge.cc
@@ -1507,6 +1507,11 @@ static LrunResult lrun(
 #endif
 
   pid_t pid = fork();
+  if (pid == -1) {
+    log_debug("failed to fork\n");
+    result.error = "cannot fork to run lrun";
+    return result;
+  }
   if (pid) {
     close(pipe_fd[1]);