Fix Event implementation

On non-windows platforms this just used a semaphore,
which meant that multiple calls to signal() would
result in wait() returning multiple times.

src/threading/event.cpp

@@ -0,0 +1,95 @@
+/*
+This file is a part of the JThread package, which contains some object-
+oriented thread wrappers for different thread implementations.
+
+Copyright (c) 2000-2006  Jori Liesenborgs (jori.liesenborgs@gmail.com)
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the "Software"),
+to deal in the Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute, sublicense,
+and/or sell copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
+*/
+
+#include "threading/event.h"
+
+#if defined(_WIN32)
+	#ifndef WIN32_LEAN_AND_MEAN
+		#define WIN32_LEAN_AND_MEAN
+	#endif
+	#include <windows.h>
+#endif
+
+
+#if __cplusplus < 201103L
+Event::Event()
+{
+#ifdef _WIN32
+	event = CreateEvent(NULL, false, false, NULL);
+#else
+	pthread_cond_init(&cv, NULL);
+	pthread_mutex_init(&mutex, NULL);
+#endif
+}
+
+Event::~Event()
+{
+#ifdef _WIN32
+	CloseHandle(event);
+#else
+	pthread_cond_destroy(&cv);
+	pthread_mutex_destroy(&mutex);
+#endif
+}
+#endif
+
+
+void Event::wait()
+{
+#if __cplusplus >= 201103L
+	MutexAutoLock lock(mutex);
+	while (!notified) {
+		cv.wait(lock);
+	}
+	notified = false;
+#elif defined(_WIN32)
+	WaitForSingleObject(event, INFINITE);
+#else
+	pthread_mutex_lock(&mutex);
+	while (!notified) {
+		pthread_cond_wait(&cv, &mutex);
+	}
+	notified = false;
+	pthread_mutex_unlock(&mutex);
+#endif
+}
+
+
+void Event::signal()
+{
+#if __cplusplus >= 201103L
+	MutexAutoLock lock(mutex);
+	notified = true;
+	cv.notify_one();
+#elif defined(_WIN32)
+	SetEvent(event);
+#else
+	pthread_mutex_lock(&mutex);
+	notified = true;
+	pthread_cond_signal(&cv);
+	pthread_mutex_unlock(&mutex);
+#endif
+}
+