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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 "OggFind.hxx"
#include "lib/xiph/OggSyncState.hxx"
#include "input/InputStream.hxx"
bool
OggFindEOS(OggSyncState &oy, ogg_stream_state &os, ogg_packet &packet)
{
while (true) {
int r = ogg_stream_packetout(&os, &packet);
if (r == 0) {
if (!oy.ExpectPageIn(os))
return false;
continue;
} else if (r > 0 && packet.e_o_s)
return true;
}
}
bool
OggSeekPageAtOffset(OggSyncState &oy, ogg_stream_state &os, InputStream &is,
offset_type offset)
{
oy.Reset();
/* reset the stream to clear any previous partial packet
data */
ogg_stream_reset(&os);
try {
is.LockSeek(offset);
} catch (...) {
return false;
}
return oy.ExpectPageSeekIn(os);
}
bool
OggSeekFindEOS(OggSyncState &oy, ogg_stream_state &os, ogg_packet &packet,
InputStream &is)
{
if (!is.KnownSize())
return false;
if (is.GetRest() < 65536)
return OggFindEOS(oy, os, packet);
if (!is.CheapSeeking())
return false;
return OggSeekPageAtOffset(oy, os, is, is.GetSize() - 65536) &&
OggFindEOS(oy, os, packet);
}