MemoryBuffer.h

/*
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 *
 * MemoryBuffer.h
 * A derived class of InputBuffer that wraps a memory buffer.
 * Copyright (C) 2012 Simon Newton
 */

#ifndef INCLUDE_OLA_IO_MEMORYBUFFER_H_
#define INCLUDE_OLA_IO_MEMORYBUFFER_H_

#include <ola/base/Macro.h>
#include <ola/io/InputBuffer.h>
#include <stdint.h>
#include <string.h>
#include <algorithm>
#include <string>

namespace ola {
namespace io {

class MemoryBuffer: public InputBufferInterface {
 public:
 explicit MemoryBuffer(const uint8_t *data, unsigned int size)
 : m_data(data),
 m_size(size),
 m_cursor(0) {
 }
 ~MemoryBuffer() {}

 unsigned int Read(uint8_t *data, unsigned int length) {
 unsigned int data_size = std::min(m_size - m_cursor, length);
 memcpy(data, m_data + m_cursor, data_size);
 m_cursor += data_size;
 return data_size;
 }

 unsigned int Read(std::string *output, unsigned int length) {
 unsigned int data_size = std::min(m_size - m_cursor, length);
 output->append(reinterpret_cast<const char*>(m_data + m_cursor),
 data_size);
 m_cursor += data_size;
 return data_size;
 }

 private:
 const uint8_t *m_data;
 const unsigned int m_size;
 unsigned int m_cursor;

 DISALLOW_COPY_AND_ASSIGN(MemoryBuffer);
};
} // namespace io
} // namespace ola
#endif // INCLUDE_OLA_IO_MEMORYBUFFER_H_