nsresult SkeletonState::GetDuration(const nsTArray<uint32_t>& aTracks,
int64_t& aDuration)
{
if (!mActive ||
mVersion < SKELETON_VERSION(4,0) ||
!HasIndex() ||
aTracks.Length() == 0)
{
return NS_ERROR_FAILURE;
}
int64_t endTime = INT64_MIN;
int64_t startTime = INT64_MAX;
for (uint32_t i=0; i<aTracks.Length(); i++) {
nsKeyFrameIndex* index = nullptr;
mIndex.Get(aTracks[i], &index);
if (!index) {
// Can't get the timestamps for one of the required tracks, fail.
return NS_ERROR_FAILURE;
}
if (index->mEndTime > endTime) {
endTime = index->mEndTime;
}
if (index->mStartTime < startTime) {
startTime = index->mStartTime;
}
}
NS_ASSERTION(endTime > startTime, "Duration must be positive");
CheckedInt64 duration = CheckedInt64(endTime) - startTime;
aDuration = duration.isValid() ? duration.value() : 0;
return duration.isValid() ? NS_OK : NS_ERROR_FAILURE;
}
int64_t OpusState::Time(int aPreSkip, int64_t aGranulepos)
{
if (aGranulepos < 0)
return -1;
// Ogg Opus always runs at a granule rate of 48 kHz.
CheckedInt64 t = CheckedInt64(aGranulepos - aPreSkip) * USECS_PER_S;
return t.isValid() ? t.value() / 48000 : -1;
}
int64_t TheoraState::StartTime(int64_t granulepos) {
if (granulepos < 0 || !mActive || mInfo.fps_numerator == 0) {
return -1;
}
CheckedInt64 t = (CheckedInt64(th_granule_frame(mCtx, granulepos)) * USECS_PER_S) * mInfo.fps_denominator;
if (!t.isValid())
return -1;
return t.value() / mInfo.fps_numerator;
}
int64_t VorbisState::Time(vorbis_info* aInfo, int64_t aGranulepos)
{
if (aGranulepos == -1 || aInfo->rate == 0) {
return -1;
}
CheckedInt64 t = CheckedInt64(aGranulepos) * USECS_PER_S;
if (!t.isValid())
t = 0;
return t.value() / aInfo->rate;
}
int64_t TheoraState::Time(th_info* aInfo, int64_t aGranulepos)
{
if (aGranulepos < 0 || aInfo->fps_numerator == 0) {
return -1;
}
// Implementation of th_granule_frame inlined here to operate
// on the th_info structure instead of the theora_state.
int shift = aInfo->keyframe_granule_shift;
ogg_int64_t iframe = aGranulepos >> shift;
ogg_int64_t pframe = aGranulepos - (iframe << shift);
int64_t frameno = iframe + pframe - TH_VERSION_CHECK(aInfo, 3, 2, 1);
CheckedInt64 t = ((CheckedInt64(frameno) + 1) * USECS_PER_S) * aInfo->fps_denominator;
if (!t.isValid())
return -1;
t /= aInfo->fps_numerator;
return t.isValid() ? t.value() : -1;
}
PRInt64
nsTheoraState::MaxKeyframeOffset()
{
// Determine the maximum time in microseconds by which a key frame could
// offset for the theora bitstream. Theora granulepos encode time as:
// ((key_frame_number << granule_shift) + frame_offset).
// Therefore the maximum possible time by which any frame could be offset
// from a keyframe is the duration of (1 << granule_shift) - 1) frames.
PRInt64 frameDuration;
// Max number of frames keyframe could possibly be offset.
PRInt64 keyframeDiff = (1 << mInfo.keyframe_granule_shift) - 1;
// Length of frame in usecs.
CheckedInt64 d = CheckedInt64(mInfo.fps_denominator) * USECS_PER_S;
if (!d.valid())
d = 0;
frameDuration = d.value() / mInfo.fps_numerator;
// Total time in usecs keyframe can be offset from any given frame.
return frameDuration * keyframeDiff;
}
// Converts from microseconds to number of audio frames, given the specified
// audio rate.
CheckedInt64 UsecsToFrames(PRInt64 aUsecs, PRUint32 aRate) {
return (CheckedInt64(aUsecs) * aRate) / USECS_PER_S;
}
// Converts from number of audio frames to microseconds, given the specified
// audio rate.
CheckedInt64 FramesToUsecs(PRInt64 aFrames, PRUint32 aRate) {
return (CheckedInt64(aFrames) * USECS_PER_S) / aRate;
}
bool
WaveReader::LoadAllChunks(nsAutoPtr<dom::HTMLMediaElement::MetadataTags> &aTags)
{
// Chunks are always word (two byte) aligned.
MOZ_ASSERT(mDecoder->GetResource()->Tell() % 2 == 0,
"LoadAllChunks called with unaligned resource");
bool loadFormatChunk = false;
bool findDataOffset = false;
for (;;) {
static const unsigned int CHUNK_HEADER_SIZE = 8;
char chunkHeader[CHUNK_HEADER_SIZE];
const char* p = chunkHeader;
if (!ReadAll(chunkHeader, sizeof(chunkHeader))) {
return false;
}
static_assert(sizeof(uint32_t) * 2 <= CHUNK_HEADER_SIZE,
"Reads would overflow chunkHeader buffer.");
uint32_t magic = ReadUint32BE(&p);
uint32_t chunkSize = ReadUint32LE(&p);
int64_t chunkStart = GetPosition();
switch (magic) {
case FRMT_CHUNK_MAGIC:
loadFormatChunk = LoadFormatChunk(chunkSize);
if (!loadFormatChunk) {
return false;
}
break;
case LIST_CHUNK_MAGIC:
if (!aTags) {
LoadListChunk(chunkSize, aTags);
}
break;
case DATA_CHUNK_MAGIC:
findDataOffset = FindDataOffset(chunkSize);
return loadFormatChunk && findDataOffset;
default:
break;
}
// RIFF chunks are two-byte aligned, so round up if necessary.
chunkSize += chunkSize % 2;
// Move forward to next chunk
CheckedInt64 forward = CheckedInt64(chunkStart) + chunkSize - GetPosition();
if (!forward.isValid() || forward.value() < 0) {
return false;
}
static const int64_t MAX_CHUNK_SIZE = 1 << 16;
static_assert(uint64_t(MAX_CHUNK_SIZE) < UINT_MAX / sizeof(char),
"MAX_CHUNK_SIZE too large for enumerator.");
nsAutoArrayPtr<char> chunk(new char[MAX_CHUNK_SIZE]);
while (forward.value() > 0) {
int64_t size = std::min(forward.value(), MAX_CHUNK_SIZE);
if (!ReadAll(chunk.get(), size)) {
return false;
}
forward -= size;
}
}
return false;
}
// Format TimeUnit as number of frames at given rate.
CheckedInt64 TimeUnitToFrames(const TimeUnit& aTime, uint32_t aRate) {
return aTime.IsValid() ? UsecsToFrames(aTime.ToMicroseconds(), aRate)
: CheckedInt64(INT64_MAX) + 1;
}
// Converts from microseconds to number of audio frames, given the specified
// audio rate.
CheckedInt64 UsecsToFrames(int64_t aUsecs, uint32_t aRate) {
return (CheckedInt64(aUsecs) * aRate) / USECS_PER_S;
}
// Converts from number of audio frames to microseconds, given the specified
// audio rate.
CheckedInt64 FramesToUsecs(int64_t aFrames, uint32_t aRate) {
return (CheckedInt64(aFrames) * USECS_PER_S) / aRate;
}
bool SkeletonState::DecodeIndex(ogg_packet* aPacket)
{
NS_ASSERTION(aPacket->bytes >= SKELETON_4_0_MIN_INDEX_LEN,
"Index must be at least minimum size");
if (!mActive) {
return false;
}
uint32_t serialno = LittleEndian::readUint32(aPacket->packet + INDEX_SERIALNO_OFFSET);
int64_t numKeyPoints = LittleEndian::readInt64(aPacket->packet + INDEX_NUM_KEYPOINTS_OFFSET);
int64_t endTime = 0, startTime = 0;
const unsigned char* p = aPacket->packet;
int64_t timeDenom = LittleEndian::readInt64(aPacket->packet + INDEX_TIME_DENOM_OFFSET);
if (timeDenom == 0) {
LOG(PR_LOG_DEBUG, ("Ogg Skeleton Index packet for stream %u has 0 "
"timestamp denominator.", serialno));
return (mActive = false);
}
// Extract the start time.
CheckedInt64 t = CheckedInt64(LittleEndian::readInt64(p + INDEX_FIRST_NUMER_OFFSET)) * USECS_PER_S;
if (!t.isValid()) {
return (mActive = false);
} else {
startTime = t.value() / timeDenom;
}
// Extract the end time.
t = LittleEndian::readInt64(p + INDEX_LAST_NUMER_OFFSET) * USECS_PER_S;
if (!t.isValid()) {
return (mActive = false);
} else {
endTime = t.value() / timeDenom;
}
// Check the numKeyPoints value read, ensure we're not going to run out of
// memory while trying to decode the index packet.
CheckedInt64 minPacketSize = (CheckedInt64(numKeyPoints) * MIN_KEY_POINT_SIZE) + INDEX_KEYPOINT_OFFSET;
if (!minPacketSize.isValid())
{
return (mActive = false);
}
int64_t sizeofIndex = aPacket->bytes - INDEX_KEYPOINT_OFFSET;
int64_t maxNumKeyPoints = sizeofIndex / MIN_KEY_POINT_SIZE;
if (aPacket->bytes < minPacketSize.value() ||
numKeyPoints > maxNumKeyPoints ||
numKeyPoints < 0)
{
// Packet size is less than the theoretical minimum size, or the packet is
// claiming to store more keypoints than it's capable of storing. This means
// that the numKeyPoints field is too large or small for the packet to
// possibly contain as many packets as it claims to, so the numKeyPoints
// field is possibly malicious. Don't try decoding this index, we may run
// out of memory.
LOG(PR_LOG_DEBUG, ("Possibly malicious number of key points reported "
"(%lld) in index packet for stream %u.",
numKeyPoints,
serialno));
return (mActive = false);
}
nsAutoPtr<nsKeyFrameIndex> keyPoints(new nsKeyFrameIndex(startTime, endTime));
p = aPacket->packet + INDEX_KEYPOINT_OFFSET;
const unsigned char* limit = aPacket->packet + aPacket->bytes;
int64_t numKeyPointsRead = 0;
CheckedInt64 offset = 0;
CheckedInt64 time = 0;
while (p < limit &&
numKeyPointsRead < numKeyPoints)
{
int64_t delta = 0;
p = ReadVariableLengthInt(p, limit, delta);
offset += delta;
if (p == limit ||
!offset.isValid() ||
offset.value() > mLength ||
offset.value() < 0)
{
return (mActive = false);
}
p = ReadVariableLengthInt(p, limit, delta);
time += delta;
if (!time.isValid() ||
time.value() > endTime ||
time.value() < startTime)
{
return (mActive = false);
}
CheckedInt64 timeUsecs = time * USECS_PER_S;
if (!timeUsecs.isValid())
return mActive = false;
timeUsecs /= timeDenom;
keyPoints->Add(offset.value(), timeUsecs.value());
numKeyPointsRead++;
}
int32_t keyPointsRead = keyPoints->Length();
if (keyPointsRead > 0) {
mIndex.Put(serialno, keyPoints.forget());
}
LOG(PR_LOG_DEBUG, ("Loaded %d keypoints for Skeleton on stream %u",
keyPointsRead, serialno));
return true;
}
