path: root/src/decoder/plugins/FfmpegIo.cxx

/*
 * Copyright (C) 2003-2015 The Music Player Daemon Project
 * http://www.musicpd.org
 *
 * This program 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; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

/* necessary because libavutil/common.h uses UINT64_C */
#define __STDC_CONSTANT_MACROS

#include "config.h"
#include "FfmpegIo.hxx"
#include "../DecoderAPI.hxx"
#include "input/InputStream.hxx"
#include "util/Error.hxx"

AvioStream::~AvioStream()
{
	av_free(io);
}

inline int
AvioStream::Read(void *dest, int size)
{
	return decoder_read(decoder, input, dest, size);
}

inline int64_t
AvioStream::Seek(int64_t pos, int whence)
{
	switch (whence) {
	case SEEK_SET:
		break;

	case SEEK_CUR:
		pos += input.GetOffset();
		break;

	case SEEK_END:
		if (!input.KnownSize())
			return -1;

		pos += input.GetSize();
		break;

	case AVSEEK_SIZE:
		if (!input.KnownSize())
			return -1;

		return input.GetSize();

	default:
		return -1;
	}

	if (!input.LockSeek(pos, IgnoreError()))
		return -1;

	return input.GetOffset();
}

int
AvioStream::_Read(void *opaque, uint8_t *buf, int size)
{
	AvioStream &stream = *(AvioStream *)opaque;

	return stream.Read(buf, size);
}

int64_t
AvioStream::_Seek(void *opaque, int64_t pos, int whence)
{
	AvioStream &stream = *(AvioStream *)opaque;

	return stream.Seek(pos, whence);
}

bool
AvioStream::Open()
{
	io = avio_alloc_context(buffer, sizeof(buffer),
				false, this,
				_Read, nullptr,
				input.IsSeekable() ? _Seek : nullptr);
	return io != nullptr;
}