/*
 * InspIRCd -- Internet Relay Chat Daemon
 *
 *   Copyright (C) 2009 Daniel De Graaf <danieldg@inspircd.org>
 *   Copyright (C) 2008 Craig Edwards <craigedwards@brainbox.cc>
 *
 * This file is part of InspIRCd.  InspIRCd is free software: you can
 * redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation, version 2.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */


#include "inspircd.h"
#include "threadengines/threadengine_pthread.h"
#include <pthread.h>
#include <signal.h>
#include <fcntl.h>

ThreadEngine::ThreadEngine(InspIRCd* Instance)
{
}

static void* entry_point(void* parameter)
{
	/* Recommended by nenolod, signal safety on a per-thread basis */
	sigset_t set;
	sigemptyset(&set);
	sigaddset(&set, SIGPIPE);
	pthread_sigmask(SIG_BLOCK, &set, NULL);

	Thread* pt = reinterpret_cast<Thread*>(parameter);
	pt->Run();
	return parameter;
}


void ThreadEngine::Start(Thread* thread)
{
	ThreadData* data = new ThreadData;
	thread->state = data;

	if (pthread_create(&data->pthread_id, NULL, entry_point, thread) != 0)
	{
		thread->state = NULL;
		delete data;
		throw CoreException("Unable to create new thread: " + std::string(strerror(errno)));
	}
}

ThreadEngine::~ThreadEngine()
{
}

void ThreadData::FreeThread(Thread* thread)
{
	thread->SetExitFlag();
	pthread_join(pthread_id, NULL);
}

#ifdef HAS_EVENTFD
#include <sys/eventfd.h>

class ThreadSignalSocket : public BufferedSocket
{
	SocketThread* parent;
 public:
	ThreadSignalSocket(SocketThread* p, InspIRCd* SI, int newfd) :
		BufferedSocket(SI, newfd, const_cast<char*>("0.0.0.0")), parent(p) {}

	~ThreadSignalSocket()
	{
	}

	void Notify()
	{
		eventfd_write(fd, 1);
	}

	virtual bool OnDataReady()
	{
		eventfd_t data;
		if (eventfd_read(fd, &data))
			return false;
		parent->OnNotify();
		return true;
	}
};

SocketThread::SocketThread(InspIRCd* SI)
{
	int fd = eventfd(0, EFD_NONBLOCK);
	if (fd < 0)
		throw new CoreException("Could not create pipe " + std::string(strerror(errno)));
	signal.sock = new ThreadSignalSocket(this, SI, fd);
}
#else

class ThreadSignalSocket : public BufferedSocket
{
	SocketThread* parent;
	int send_fd;
 public:
	ThreadSignalSocket(SocketThread* p, InspIRCd* SI, int recvfd, int sendfd) :
		BufferedSocket(SI, recvfd, const_cast<char*>("0.0.0.0")), parent(p), send_fd(sendfd)  {}

	~ThreadSignalSocket()
	{
		close(send_fd);
	}

	void Notify()
	{
		char dummy = '*';
		write(send_fd, &dummy, 1);
	}

	virtual bool OnDataReady()
	{
		char data;
		if (read(this->fd, &data, 1) <= 0)
			return false;
		parent->OnNotify();
		return true;
	}
};

SocketThread::SocketThread(InspIRCd* SI)
{
	int fds[2];
	if (pipe(fds))
		throw new CoreException("Could not create pipe " + std::string(strerror(errno)));
	signal.sock = new ThreadSignalSocket(this, SI, fds[0], fds[1]);
}
#endif

void SocketThread::NotifyParent()
{
	signal.sock->Notify();
}

SocketThread::~SocketThread()
{
}