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/*
* Copyright 2003-2018 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.
*/
#include "OggDecoder.hxx"
#include "lib/xiph/OggFind.hxx"
#include "input/InputStream.hxx"
#include <exception>
/**
* Load the end-of-stream packet and restore the previous file
* position.
*/
bool
OggDecoder::LoadEndPacket(ogg_packet &packet) const
{
if (!input_stream.CheapSeeking())
/* we do this for local files only, because seeking
around remote files is expensive and not worth the
trouble */
return false;
const auto old_offset = input_stream.GetOffset();
/* create temporary Ogg objects for seeking and parsing the
EOS packet */
bool result;
{
DecoderReader reader(client, input_stream);
OggSyncState sync2(reader);
OggStreamState stream2(GetSerialNo());
result = OggSeekFindEOS(sync2, stream2, packet,
input_stream);
}
/* restore the previous file position */
try {
input_stream.LockSeek(old_offset);
} catch (...) {
}
return result;
}
ogg_int64_t
OggDecoder::LoadEndGranulePos() const
{
ogg_packet packet;
if (!LoadEndPacket(packet))
return -1;
return packet.granulepos;
}
void
OggDecoder::SeekGranulePos(ogg_int64_t where_granulepos)
{
assert(IsSeekable());
/* interpolate the file offset where we expect to find the
given granule position */
/* TODO: implement binary search */
offset_type offset(where_granulepos * input_stream.GetSize()
/ end_granulepos);
input_stream.LockSeek(offset);
PostSeek();
}