From: Marco Costalba <mcostalba@gmail.com>
Date: Mon, 2 Jan 2012 13:37:44 +0000 (+0100)
Subject: Revert cond_signal() fix
X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=cb1709ef5e6f96d8db44854b42b67fb524214717;hp=67338e6f322b8f8ec0d897815e16a87937efc9b0

Revert cond_signal() fix

It seems it yields to missing wake-up events with the
result of SF loosing on time as reported by many people.

So revert the patch and use a more robust approach: assume
there can be spurious wake ups events and make the code to
work also in those cases.

While debugging I found that WaitForSingleObject() had wrong
parameter 0 instead of INFINITE yielding to a crash while
exiting under Windows, strangely unnoticed til now.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
---

diff --git a/src/lock.h b/src/lock.h
index 0af1443d..3b3de1ac 100644
--- a/src/lock.h
+++ b/src/lock.h
@@ -75,8 +75,8 @@ typedef HANDLE WaitCondition;
 #  define cond_init(x) { *x = CreateEvent(0, FALSE, FALSE, 0); }
 #  define cond_destroy(x) CloseHandle(*x)
 #  define cond_signal(x) SetEvent(*x)
-#  define cond_wait(x,y) { ResetEvent(*x); lock_release(y); WaitForSingleObject(*x, INFINITE); lock_grab(y); }
-#  define cond_timedwait(x,y,z) { ResetEvent(*x); lock_release(y); WaitForSingleObject(*x,z); lock_grab(y); }
+#  define cond_wait(x,y) { lock_release(y); WaitForSingleObject(*x, INFINITE); lock_grab(y); }
+#  define cond_timedwait(x,y,z) { lock_release(y); WaitForSingleObject(*x,z); lock_grab(y); }
 
 #endif
 
diff --git a/src/thread.cpp b/src/thread.cpp
index bc26d4df..394e0698 100644
--- a/src/thread.cpp
+++ b/src/thread.cpp
@@ -202,7 +202,7 @@ void ThreadsManager::exit() {
 
       // Wait for thread termination
 #if defined(_MSC_VER)
-      WaitForSingleObject(threads[i].handle, 0);
+      WaitForSingleObject(threads[i].handle, INFINITE);
       CloseHandle(threads[i].handle);
 #else
       pthread_join(threads[i].handle, NULL);
@@ -452,7 +452,8 @@ void ThreadsManager::start_thinking(const Position& pos, const LimitsType& limit
   cond_signal(&main.sleepCond); // Wake up main thread and start searching
 
   if (!asyncMode)
-      cond_wait(&sleepCond, &main.sleepLock);
+      while (!main.do_sleep)
+          cond_wait(&sleepCond, &main.sleepLock);
 
   lock_release(&main.sleepLock);
 }