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/*
* Copyright 2003-2020 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 "OggVisitor.hxx"
#include <stdexcept>
#include <utility>
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)
{
const bool _post_seek = std::exchange(post_seek, false);
if (packet.b_o_s) {
if (_post_seek)
/* ignore the BOS packet after seeking */
return;
EndStream();
has_stream = true;
OnOggBeginning(packet);
return;
}
if (!has_stream)
/* fail if BOS is missing */
throw std::runtime_error("BOS packet expected");
OnOggPacket(packet);
if (packet.e_o_s) {
EndStream();
return;
}
}
inline void
OggVisitor::HandlePackets()
{
ogg_packet packet;
while (stream.PacketOut(packet) == 1)
HandlePacket(packet);
}
void
OggVisitor::Visit()
{
do {
HandlePackets();
} while (ReadNextPage());
}
void
OggVisitor::PostSeek(uint64_t offset)
{
sync.Reset();
sync.SetOffset(offset);
/* 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);
post_seek = true;
}
ogg_int64_t
OggVisitor::ReadGranulepos() noexcept
{
ogg_packet packet;
while (stream.PacketOut(packet) == 1)
if (packet.granulepos >= 0)
return packet.granulepos;
return -1;
}