From 017a0fd20d677294b7af427b10654156512a7c77 Mon Sep 17 00:00:00 2001
From: Vladislav Vaintroub <vvaintroub@mysql.com>
Date: Wed, 30 Sep 2009 00:19:00 +0200
Subject: Bug #47731 mtr freezes for many seconds when process to be killed has
 already gone.

The problem is that safe_kill_win fails to detect a dead process. OpenProcess() will
succeed even after the process died, it will first fail after the last handle to process
is closed.

To fix the problem, check process status with GetExitCodeProcess() and consider
process to be dead if the exit code returned by this routine is not STILL_ALIVE.
---
 mysql-test/lib/My/SafeProcess/safe_kill_win.cc | 28 ++++++++++++++++++++------
 1 file changed, 22 insertions(+), 6 deletions(-)

(limited to 'mysql-test/lib/My/SafeProcess/safe_kill_win.cc')

diff --git a/mysql-test/lib/My/SafeProcess/safe_kill_win.cc b/mysql-test/lib/My/SafeProcess/safe_kill_win.cc
index c6256fd92e1..963a02c8099 100755
--- a/mysql-test/lib/My/SafeProcess/safe_kill_win.cc
+++ b/mysql-test/lib/My/SafeProcess/safe_kill_win.cc
@@ -30,7 +30,7 @@ int main(int argc, const char** argv )
   DWORD pid= -1;
   HANDLE shutdown_event;
   char safe_process_name[32]= {0};
-  int retry_open_event= 100;
+  int retry_open_event= 2;
   /* Ignore any signals */
   signal(SIGINT,   SIG_IGN);
   signal(SIGBREAK, SIG_IGN);
@@ -51,15 +51,31 @@ int main(int argc, const char** argv )
   {
      /*
       Check if the process is alive, otherwise there is really
-      no idea to retry the open of the event
+      no sense to retry the open of the event
      */
     HANDLE process;
-    if ((process= OpenProcess(SYNCHRONIZE, FALSE, pid)) == NULL)
+    DWORD exit_code;
+    process= OpenProcess(SYNCHRONIZE| PROCESS_QUERY_INFORMATION, FALSE, pid);
+    if (!process)
     {
-      fprintf(stderr, "Could not open event or process %d, error: %d\n",
-            pid, GetLastError());
-      exit(3);
+      /* Already died */
+      exit(1);
+    }
+
+    if (!GetExitCodeProcess(process,&exit_code))
+    {
+       fprintf(stderr,  "GetExitCodeProcess failed, pid= %d, err= %d\n",
+         pid, GetLastError());
+       exit(1);
     }
+
+    if (exit_code != STILL_ACTIVE)
+    {
+       /* Already died */
+       CloseHandle(process);
+       exit(2);
+    }
+
     CloseHandle(process);
 
     if (retry_open_event--)
-- 
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