mpd/src/lib/xiph/OggVisitor.cxx
2017-01-03 20:48:59 +01:00

102 lines
2.0 KiB
C++

/*
* Copyright 2003-2017 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 "config.h"
#include "OggVisitor.hxx"
#include <stdexcept>
void
OggVisitor::EndStream()
{
if (!has_stream)
return;
has_stream = false;
OnOggEnd();
}
inline bool
OggVisitor::ReadNextPage()
{
ogg_page page;
if (!sync.ExpectPage(page))
return false;
const auto page_serialno = ogg_page_serialno(&page);
if (page_serialno != stream.GetSerialNo()) {
EndStream();
stream.Reinitialize(page_serialno);
}
stream.PageIn(page);
return true;
}
inline void
OggVisitor::HandlePacket(const ogg_packet &packet)
{
if (packet.b_o_s) {
EndStream();
has_stream = true;
OnOggBeginning(packet);
return;
}
if (!has_stream)
/* fail if BOS is missing */
throw std::runtime_error("BOS packet expected");
if (packet.e_o_s) {
EndStream();
return;
}
OnOggPacket(packet);
}
inline void
OggVisitor::HandlePackets()
{
ogg_packet packet;
while (stream.PacketOut(packet) == 1)
HandlePacket(packet);
}
void
OggVisitor::Visit()
{
do {
HandlePackets();
} while (ReadNextPage());
}
void
OggVisitor::PostSeek()
{
sync.Reset();
/* reset the stream to clear any previous partial packet
data */
stream.Reset();
/* find the next Ogg page and feed it into the stream */
sync.ExpectPageSeekIn(stream);
}