Clementine-audio-player-Mac.../3rdparty/taglib/ogg/oggpage.cpp

309 lines
9.1 KiB
C++

/***************************************************************************
copyright : (C) 2002 - 2008 by Scott Wheeler
email : wheeler@kde.org
***************************************************************************/
/***************************************************************************
* This library is free software; you can redistribute it and/or modify *
* it under the terms of the GNU Lesser General Public License version *
* 2.1 as published by the Free Software Foundation. *
* *
* This library 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 *
* Lesser General Public License for more details. *
* *
* You should have received a copy of the GNU Lesser General Public *
* License along with this library; if not, write to the Free Software *
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA *
* 02110-1301 USA *
* *
* Alternatively, this file is available under the Mozilla Public *
* License Version 1.1. You may obtain a copy of the License at *
* http://www.mozilla.org/MPL/ *
***************************************************************************/
#include <algorithm>
#include <tstring.h>
#include <tdebug.h>
#include "oggpage.h"
#include "oggpageheader.h"
#include "oggfile.h"
using namespace TagLib;
class Ogg::Page::PagePrivate
{
public:
PagePrivate(File *f = 0, long pageOffset = -1) :
file(f),
fileOffset(pageOffset),
header(f, pageOffset),
firstPacketIndex(-1) {}
File *file;
long fileOffset;
PageHeader header;
int firstPacketIndex;
ByteVectorList packets;
};
////////////////////////////////////////////////////////////////////////////////
// public members
////////////////////////////////////////////////////////////////////////////////
Ogg::Page::Page(Ogg::File *file, long pageOffset) :
d(new PagePrivate(file, pageOffset))
{
}
Ogg::Page::~Page()
{
delete d;
}
long Ogg::Page::fileOffset() const
{
return d->fileOffset;
}
const Ogg::PageHeader *Ogg::Page::header() const
{
return &d->header;
}
int Ogg::Page::pageSequenceNumber() const
{
return d->header.pageSequenceNumber();
}
void Ogg::Page::setPageSequenceNumber(int sequenceNumber)
{
d->header.setPageSequenceNumber(sequenceNumber);
}
int Ogg::Page::firstPacketIndex() const
{
return d->firstPacketIndex;
}
void Ogg::Page::setFirstPacketIndex(int index)
{
d->firstPacketIndex = index;
}
Ogg::Page::ContainsPacketFlags Ogg::Page::containsPacket(int index) const
{
const int lastPacketIndex = d->firstPacketIndex + packetCount() - 1;
if(index < d->firstPacketIndex || index > lastPacketIndex)
return DoesNotContainPacket;
ContainsPacketFlags flags = DoesNotContainPacket;
if(index == d->firstPacketIndex)
flags = ContainsPacketFlags(flags | BeginsWithPacket);
if(index == lastPacketIndex)
flags = ContainsPacketFlags(flags | EndsWithPacket);
// If there's only one page and it's complete:
if(packetCount() == 1 &&
!d->header.firstPacketContinued() &&
d->header.lastPacketCompleted())
{
flags = ContainsPacketFlags(flags | CompletePacket);
}
// Or if there is more than one page and the page is
// (a) the first page and it's complete or
// (b) the last page and it's complete or
// (c) a page in the middle.
else if(packetCount() > 1 &&
((flags & BeginsWithPacket && !d->header.firstPacketContinued()) ||
(flags & EndsWithPacket && d->header.lastPacketCompleted()) ||
(!(flags & BeginsWithPacket) && !(flags & EndsWithPacket))))
{
flags = ContainsPacketFlags(flags | CompletePacket);
}
return flags;
}
unsigned int Ogg::Page::packetCount() const
{
return d->header.packetSizes().size();
}
ByteVectorList Ogg::Page::packets() const
{
if(!d->packets.isEmpty())
return d->packets;
ByteVectorList l;
if(d->file && d->header.isValid()) {
d->file->seek(d->fileOffset + d->header.size());
List<int> packetSizes = d->header.packetSizes();
List<int>::ConstIterator it = packetSizes.begin();
for(; it != packetSizes.end(); ++it)
l.append(d->file->readBlock(*it));
}
else
debug("Ogg::Page::packets() -- attempting to read packets from an invalid page.");
return l;
}
int Ogg::Page::size() const
{
return d->header.size() + d->header.dataSize();
}
ByteVector Ogg::Page::render() const
{
ByteVector data;
data.append(d->header.render());
if(d->packets.isEmpty()) {
if(d->file) {
d->file->seek(d->fileOffset + d->header.size());
data.append(d->file->readBlock(d->header.dataSize()));
}
else
debug("Ogg::Page::render() -- this page is empty!");
}
else {
ByteVectorList::ConstIterator it = d->packets.begin();
for(; it != d->packets.end(); ++it)
data.append(*it);
}
// Compute and set the checksum for the Ogg page. The checksum is taken over
// the entire page with the 4 bytes reserved for the checksum zeroed and then
// inserted in bytes 22-25 of the page header.
const ByteVector checksum = ByteVector::fromUInt(data.checksum(), false);
std::copy(checksum.begin(), checksum.end(), data.begin() + 22);
return data;
}
List<Ogg::Page *> Ogg::Page::paginate(const ByteVectorList &packets,
PaginationStrategy strategy,
unsigned int streamSerialNumber,
int firstPage,
bool firstPacketContinued,
bool lastPacketCompleted,
bool containsLastPacket)
{
// SplitSize must be a multiple of 255 in order to get the lacing values right
// create pages of about 8KB each
static const unsigned int SplitSize = 32 * 255;
// Force repagination if the segment table will exceed the size limit.
if(strategy != Repaginate) {
size_t tableSize = 0;
for(ByteVectorList::ConstIterator it = packets.begin(); it != packets.end(); ++it)
tableSize += it->size() / 255 + 1;
if(tableSize > 255)
strategy = Repaginate;
}
List<Page *> l;
// Handle creation of multiple pages with appropriate pagination.
if(strategy == Repaginate) {
int pageIndex = firstPage;
for(ByteVectorList::ConstIterator it = packets.begin(); it != packets.end(); ++it) {
const bool lastPacketInList = (it == --packets.end());
// mark very first packet?
bool continued = (firstPacketContinued && it == packets.begin());
unsigned int pos = 0;
while(pos < it->size()) {
const bool lastSplit = (pos + SplitSize >= it->size());
ByteVectorList packetList;
packetList.append(it->mid(pos, SplitSize));
l.append(new Page(packetList,
streamSerialNumber,
pageIndex,
continued,
lastSplit && (lastPacketInList ? lastPacketCompleted : true),
lastSplit && (containsLastPacket && lastPacketInList)));
pageIndex++;
continued = true;
pos += SplitSize;
}
}
}
else {
l.append(new Page(packets,
streamSerialNumber,
firstPage,
firstPacketContinued,
lastPacketCompleted,
containsLastPacket));
}
return l;
}
Ogg::Page* Ogg::Page::getCopyWithNewPageSequenceNumber(int /*sequenceNumber*/)
{
debug("Ogg::Page::getCopyWithNewPageSequenceNumber() -- This function is obsolete. Returning null.");
return 0;
}
////////////////////////////////////////////////////////////////////////////////
// protected members
////////////////////////////////////////////////////////////////////////////////
Ogg::Page::Page(const ByteVectorList &packets,
unsigned int streamSerialNumber,
int pageNumber,
bool firstPacketContinued,
bool lastPacketCompleted,
bool containsLastPacket) :
d(new PagePrivate())
{
d->header.setFirstPageOfStream(pageNumber == 0 && !firstPacketContinued);
d->header.setLastPageOfStream(containsLastPacket);
d->header.setFirstPacketContinued(firstPacketContinued);
d->header.setLastPacketCompleted(lastPacketCompleted);
d->header.setStreamSerialNumber(streamSerialNumber);
d->header.setPageSequenceNumber(pageNumber);
// Build a page from the list of packets.
ByteVector data;
List<int> packetSizes;
for(ByteVectorList::ConstIterator it = packets.begin(); it != packets.end(); ++it) {
packetSizes.append((*it).size());
data.append(*it);
}
d->packets = packets;
d->header.setPacketSizes(packetSizes);
}