Merge moksha.local:/Users/davi/mysql/push/mysql-5.0-runtime

into  moksha.local:/Users/davi/mysql/push/mysql-5.1-runtime

include/config-win.h

@@ -21,6 +21,9 @@
 /* We have to do this define before including windows.h to get the AWE API
 functions */
 #define _WIN32_WINNT     0x0500
+#else
+/* Get NT 4.0 functions */
+#define _WIN32_WINNT     0x0400
 #endif
 
 #if defined(_MSC_VER) && _MSC_VER >= 1400

include/my_pthread.h

@@ -101,6 +101,7 @@ struct timespec {
 
 void win_pthread_init(void);
 int win_pthread_setspecific(void *A,void *B,uint length);
+int win_pthread_mutex_trylock(pthread_mutex_t *mutex);
 int pthread_create(pthread_t *,pthread_attr_t *,pthread_handler,void *);
 int pthread_cond_init(pthread_cond_t *cond, const pthread_condattr_t *attr);
 int pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex);
@@ -156,7 +157,7 @@ void pthread_exit(void *a);	 /* was #define pthread_exit(A) ExitThread(A)*/
 #define pthread_equal(A,B) ((A) == (B))
 #define pthread_mutex_init(A,B)  (InitializeCriticalSection(A),0)
 #define pthread_mutex_lock(A)	 (EnterCriticalSection(A),0)
-#define pthread_mutex_trylock(A) (WaitForSingleObject((A), 0) == WAIT_TIMEOUT)
+#define pthread_mutex_trylock(A) win_pthread_mutex_trylock((A))
 #define pthread_mutex_unlock(A)  LeaveCriticalSection(A)
 #define pthread_mutex_destroy(A) DeleteCriticalSection(A)
 #define my_pthread_setprio(A,B)  SetThreadPriority(GetCurrentThread(), (B))
@@ -472,7 +473,7 @@ typedef struct st_safe_mutex_info_t
 
 int safe_mutex_init(safe_mutex_t *mp, const pthread_mutexattr_t *attr,
                     const char *file, uint line);
-int safe_mutex_lock(safe_mutex_t *mp,const char *file, uint line);
+int safe_mutex_lock(safe_mutex_t *mp, my_bool try_lock, const char *file, uint line);
 int safe_mutex_unlock(safe_mutex_t *mp,const char *file, uint line);
 int safe_mutex_destroy(safe_mutex_t *mp,const char *file, uint line);
 int safe_cond_wait(pthread_cond_t *cond, safe_mutex_t *mp,const char *file,
@@ -495,12 +496,12 @@ void safe_mutex_end(FILE *file);
 #undef pthread_cond_timedwait
 #undef pthread_mutex_trylock
 #define pthread_mutex_init(A,B) safe_mutex_init((A),(B),__FILE__,__LINE__)
-#define pthread_mutex_lock(A) safe_mutex_lock((A),__FILE__,__LINE__)
+#define pthread_mutex_lock(A) safe_mutex_lock((A), FALSE, __FILE__, __LINE__)
 #define pthread_mutex_unlock(A) safe_mutex_unlock((A),__FILE__,__LINE__)
 #define pthread_mutex_destroy(A) safe_mutex_destroy((A),__FILE__,__LINE__)
 #define pthread_cond_wait(A,B) safe_cond_wait((A),(B),__FILE__,__LINE__)
 #define pthread_cond_timedwait(A,B,C) safe_cond_timedwait((A),(B),(C),__FILE__,__LINE__)
-#define pthread_mutex_trylock(A) pthread_mutex_lock(A)
+#define pthread_mutex_trylock(A) safe_mutex_lock((A), TRUE, __FILE__, __LINE__)
 #define pthread_mutex_t safe_mutex_t
 #define safe_mutex_assert_owner(mp) \
           DBUG_ASSERT((mp)->count > 0 && \

mysys/my_winthread.c

@@ -40,6 +40,29 @@ void win_pthread_init(void)
   pthread_mutex_init(&THR_LOCK_thread,MY_MUTEX_INIT_FAST);
 }
 
+
+/**
+   Adapter to @c pthread_mutex_trylock()
+
+   @retval 0      Mutex was acquired
+   @retval EBUSY  Mutex was already locked by a thread
+ */
+int
+win_pthread_mutex_trylock(pthread_mutex_t *mutex)
+{
+  if (TryEnterCriticalSection(mutex))
+  {
+    /* Don't allow recursive lock */
+    if (mutex->RecursionCount > 1){
+      LeaveCriticalSection(mutex);
+      return EBUSY;
+    }
+    return 0;
+  }
+  return EBUSY;
+}
+
+
 /*
 ** We have tried to use '_beginthreadex' instead of '_beginthread' here
 ** but in this case the program leaks about 512 characters for each

mysys/thr_mutex.c

@@ -91,7 +91,7 @@ int safe_mutex_init(safe_mutex_t *mp,
 }
 
 
-int safe_mutex_lock(safe_mutex_t *mp,const char *file, uint line)
+int safe_mutex_lock(safe_mutex_t *mp, my_bool try_lock, const char *file, uint line)
 {
   int error;
   if (!mp->file)
@@ -104,15 +104,50 @@ int safe_mutex_lock(safe_mutex_t *mp,const char *file, uint line)
   }
 
   pthread_mutex_lock(&mp->global);
-  if (mp->count > 0 && pthread_equal(pthread_self(),mp->thread))
+  if (mp->count > 0)
   {
-    fprintf(stderr,"safe_mutex: Trying to lock mutex at %s, line %d, when the mutex was already locked at %s, line %d in thread %s\n",
+    if (try_lock)
+    {
+      pthread_mutex_unlock(&mp->global);
+      return EBUSY;
+    }
+    else if (pthread_equal(pthread_self(),mp->thread))
+    {
+      fprintf(stderr,
+              "safe_mutex: Trying to lock mutex at %s, line %d, when the"
+              " mutex was already locked at %s, line %d in thread %s\n",
               file,line,mp->file, mp->line, my_thread_name());
       fflush(stderr);
       abort();
     }
+  }
   pthread_mutex_unlock(&mp->global);
-  error=pthread_mutex_lock(&mp->mutex);
+
+  /*
+    If we are imitating trylock(), we need to take special
+    precautions.
+
+    - We cannot use pthread_mutex_lock() only since another thread can
+      overtake this thread and take the lock before this thread
+      causing pthread_mutex_trylock() to hang. In this case, we should
+      just return EBUSY. Hence, we use pthread_mutex_trylock() to be
+      able to return immediately.
+
+    - We cannot just use trylock() and continue execution below, since
+      this would generate an error and abort execution if the thread
+      was overtaken and trylock() returned EBUSY . In this case, we
+      instead just return EBUSY, since this is the expected behaviour
+      of trylock().
+   */
+  if (try_lock)
+  {
+    error= pthread_mutex_trylock(&mp->mutex);
+    if (error == EBUSY)
+      return error;
+  }
+  else
+    error= pthread_mutex_lock(&mp->mutex);
+
   if (error || (error=pthread_mutex_lock(&mp->global)))
   {
     fprintf(stderr,"Got error %d when trying to lock mutex at %s, line %d\n",