Mac: ensure child processes are properly reaped -- eliminate Helper zombies.

BUG=32001
TEST=Surf a lot. Then close all Chrome/Chromium windows. Make sure there aren't any zombie Chrome/Chromium Helper processes (run "ps -Al" and look for things with status containing 'Z').

Review URL: http://codereview.chromium.org/542042

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@36124 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 20 insertions, 2 deletions

diff --git a/chrome/common/process_watcher_mac.cc b/chrome/common/process_watcher_mac.cc
index 2d5d185..be5b9f7 100644
--- a/chrome/common/process_watcher_mac.cc
+++ b/chrome/common/process_watcher_mac.cc
@@ -42,7 +42,9 @@ void WaitForChildToDie(pid_t child, unsigned timeout) {
   int result = HANDLE_EINTR(kevent(kq, &event_to_add, 1, NULL, 0, NULL));
   if (result == -1 && errno == ESRCH) {
     // A "No Such Process" error is fine, the process may have died already
-    // and been reaped by someone else.
+    // and been reaped by someone else. But make sure that it was/is reaped.
+    // Don't report an error in case it was already reaped.
+    HANDLE_EINTR(waitpid(child, NULL, WNOHANG));
     return;
   }
 
diff --git a/chrome/common/process_watcher_unittest.cc b/chrome/common/process_watcher_unittest.cc
index 505a468..af4aaa2 100644
--- a/chrome/common/process_watcher_unittest.cc
+++ b/chrome/common/process_watcher_unittest.cc
@@ -39,10 +39,26 @@ TEST_F(ProcessWatcherTest, DelayedTermination) {
 }
 
 MULTIPROCESS_TEST_MAIN(process_watcher_test_never_die) {
-  while(1){
+  while (1) {
     sleep(500);
   }
   return 0;
 }
 
+TEST_F(ProcessWatcherTest, ImmediateTermination) {
+  base::ProcessHandle child_process =
+      SpawnChild(L"process_watcher_test_die_immediately");
+  // Give it time to die.
+  sleep(2);
+  ProcessWatcher::EnsureProcessTerminated(child_process);
+
+  // Check that process was really killed.
+  EXPECT_TRUE(IsProcessDead(child_process));
+  base::CloseProcessHandle(child_process);
+}
+
+MULTIPROCESS_TEST_MAIN(process_watcher_test_die_immediately) {
+  return 0;
+}
+
 #endif  // OS_POSIX