// Copyright 2016 The SwiftShader Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//    http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include "Thread.hpp"

namespace rr {

Thread::Thread(void (*threadFunction)(void *parameters), void *parameters)
{
	Event init;
	Entry entry = { threadFunction, parameters, &init };

#if defined(_WIN32)
	handle = CreateThread(NULL, 1024 * 1024, startFunction, &entry, 0, NULL);
#else
	pthread_create(&handle, NULL, startFunction, &entry);
#endif

	init.wait();
}

Thread::~Thread()
{
	join();  // Make threads exit before deleting them to not block here
}

void Thread::join()
{
	if(!hasJoined)
	{
#if defined(_WIN32)
		WaitForSingleObject(handle, INFINITE);
		CloseHandle(handle);
#else
		pthread_join(handle, NULL);
#endif

		hasJoined = true;
	}
}

#if defined(_WIN32)
unsigned long __stdcall Thread::startFunction(void *parameters)
{
	Entry entry = *(Entry *)parameters;
	entry.init->signal();
	entry.threadFunction(entry.threadParameters);
	return 0;
}
#else
void *Thread::startFunction(void *parameters)
{
	Entry entry = *(Entry *)parameters;
	entry.init->signal();
	entry.threadFunction(entry.threadParameters);
	return nullptr;
}
#endif

Event::Event()
{
#if defined(_WIN32)
	handle = CreateEvent(NULL, FALSE, FALSE, NULL);
#else
	pthread_cond_init(&handle, NULL);
	pthread_mutex_init(&mutex, NULL);
	signaled = false;
#endif
}

Event::~Event()
{
#if defined(_WIN32)
	CloseHandle(handle);
#else
	pthread_cond_destroy(&handle);
	pthread_mutex_destroy(&mutex);
#endif
}

}  // namespace rr