execserver/xsPosixFileReader.cpp

/*-------------------------------------------------------------------------
 * drawElements Quality Program Execution Server
 * ---------------------------------------------
 *
 * Copyright 2014 The Android Open Source Project
 *
 * 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.
 *
 *//*!
 * \file
 * \brief File Reader.
 *//*--------------------------------------------------------------------*/

#include "xsPosixFileReader.hpp"

#include <vector>

namespace xs
{
namespace posix
{

FileReader::FileReader (int blockSize, int numBlocks)
	: m_file		(DE_NULL)
	, m_buf			(blockSize, numBlocks)
	, m_isRunning	(false)
{
}

FileReader::~FileReader (void)
{
}

void FileReader::start (const char* filename)
{
	DE_ASSERT(!m_isRunning);

	m_file = deFile_create(filename, DE_FILEMODE_OPEN|DE_FILEMODE_READ);
	XS_CHECK(m_file);

#if (DE_OS != DE_OS_IOS)
	// Set to non-blocking mode.
	if (!deFile_setFlags(m_file, DE_FILE_NONBLOCKING))
	{
		deFile_destroy(m_file);
		m_file = DE_NULL;
		XS_FAIL("Failed to set non-blocking mode");
	}
#endif

	m_isRunning	= true;

	de::Thread::start();
}

void FileReader::run (void)
{
	std::vector<deUint8>	tmpBuf		(FILEREADER_TMP_BUFFER_SIZE);
	deInt64					numRead		= 0;

	while (!m_buf.isCanceled())
	{
		deFileResult result = deFile_read(m_file, &tmpBuf[0], (deInt64)tmpBuf.size(), &numRead);

		if (result == DE_FILERESULT_SUCCESS)
		{
			// Write to buffer.
			try
			{
				m_buf.write((int)numRead, &tmpBuf[0]);
				m_buf.flush();
			}
			catch (const ThreadedByteBuffer::CanceledException&)
			{
				// Canceled.
				break;
			}
		}
		else if (result == DE_FILERESULT_END_OF_FILE ||
				 result == DE_FILERESULT_WOULD_BLOCK)
		{
			// Wait for more data.
			deSleep(FILEREADER_IDLE_SLEEP);
		}
		else
			break; // Error.
	}
}

void FileReader::stop (void)
{
	if (!m_isRunning)
		return; // Nothing to do.

	m_buf.cancel();

	// Join thread.
	join();

	// Destroy file.
	deFile_destroy(m_file);
	m_file = DE_NULL;

	// Reset buffer.
	m_buf.clear();

	m_isRunning = false;
}

} // posix
} // xs