bool
WaveReader::GetNextChunk(uint32_t* aChunk, uint32_t* aChunkSize)
{
NS_ABORT_IF_FALSE(aChunk, "Must have aChunk");
NS_ABORT_IF_FALSE(aChunkSize, "Must have aChunkSize");
NS_ABORT_IF_FALSE(mDecoder->GetResource()->Tell() % 2 == 0,
"GetNextChunk called with unaligned resource");
char chunkHeader[CHUNK_HEADER_SIZE];
const char* p = chunkHeader;
if (!ReadAll(chunkHeader, sizeof(chunkHeader))) {
return false;
}
PR_STATIC_ASSERT(sizeof(uint32_t) * 2 <= CHUNK_HEADER_SIZE);
*aChunk = ReadUint32BE(&p);
*aChunkSize = ReadUint32LE(&p);
return true;
}
bool
WaveReader::GetNextChunk(uint32_t* aChunk, uint32_t* aChunkSize)
{
MOZ_ASSERT(aChunk, "Must have aChunk");
MOZ_ASSERT(aChunkSize, "Must have aChunkSize");
MOZ_ASSERT(mDecoder->GetResource()->Tell() % 2 == 0,
"GetNextChunk called with unaligned resource");
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.");
*aChunk = ReadUint32BE(&p);
*aChunkSize = ReadUint32LE(&p);
return true;
}
bool
WaveReader::ScanForwardUntil(uint32_t aWantedChunk, uint32_t* aChunkSize)
{
NS_ABORT_IF_FALSE(aChunkSize, "Require aChunkSize argument");
*aChunkSize = 0;
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;
}
PR_STATIC_ASSERT(sizeof(uint32_t) * 2 <= CHUNK_HEADER_SIZE);
uint32_t magic = ReadUint32BE(&p);
uint32_t chunkSize = ReadUint32LE(&p);
if (magic == aWantedChunk) {
*aChunkSize = chunkSize;
return true;
}
// RIFF chunks are two-byte aligned, so round up if necessary.
chunkSize += chunkSize % 2;
static const unsigned int MAX_CHUNK_SIZE = 1 << 16;
PR_STATIC_ASSERT(MAX_CHUNK_SIZE < UINT_MAX / sizeof(char));
nsAutoArrayPtr<char> chunk(new char[MAX_CHUNK_SIZE]);
while (chunkSize > 0) {
uint32_t size = NS_MIN(chunkSize, MAX_CHUNK_SIZE);
if (!ReadAll(chunk.get(), size)) {
return false;
}
chunkSize -= size;
}
}
}
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;
}
bool
WaveReader::LoadListChunk(uint32_t aChunkSize,
nsAutoPtr<dom::HTMLMediaElement::MetadataTags> &aTags)
{
// List chunks are always word (two byte) aligned.
MOZ_ASSERT(mDecoder->GetResource()->Tell() % 2 == 0,
"LoadListChunk called with unaligned resource");
static const unsigned int MAX_CHUNK_SIZE = 1 << 16;
static_assert(uint64_t(MAX_CHUNK_SIZE) < UINT_MAX / sizeof(char),
"MAX_CHUNK_SIZE too large for enumerator.");
if (aChunkSize > MAX_CHUNK_SIZE || aChunkSize < 4) {
return false;
}
nsAutoArrayPtr<char> chunk(new char[aChunkSize]);
if (!ReadAll(chunk.get(), aChunkSize)) {
return false;
}
static const uint32_t INFO_LIST_MAGIC = 0x494e464f;
const char* p = chunk.get();
if (ReadUint32BE(&p) != INFO_LIST_MAGIC) {
return false;
}
const waveIdToName ID_TO_NAME[] = {
{ 0x49415254, NS_LITERAL_CSTRING("artist") }, // IART
{ 0x49434d54, NS_LITERAL_CSTRING("comments") }, // ICMT
{ 0x49474e52, NS_LITERAL_CSTRING("genre") }, // IGNR
{ 0x494e414d, NS_LITERAL_CSTRING("name") }, // INAM
};
const char* const end = chunk.get() + aChunkSize;
aTags = new dom::HTMLMediaElement::MetadataTags;
while (p + 8 < end) {
uint32_t id = ReadUint32BE(&p);
// Uppercase tag id, inspired by GStreamer's Wave parser.
id &= 0xDFDFDFDF;
uint32_t length = ReadUint32LE(&p);
// Subchunk shall not exceed parent chunk.
if (uint32_t(end - p) < length) {
break;
}
// Wrap the string, adjusting length to account for optional
// null termination in the chunk.
nsCString val(p, length);
if (length > 0 && val[length - 1] == '\0') {
val.SetLength(length - 1);
}
// Chunks in List::INFO are always word (two byte) aligned. So round up if
// necessary.
length += length % 2;
p += length;
if (!IsUTF8(val)) {
continue;
}
for (size_t i = 0; i < mozilla::ArrayLength(ID_TO_NAME); ++i) {
if (id == ID_TO_NAME[i].id) {
aTags->Put(ID_TO_NAME[i].name, val);
break;
}
}
}
return true;
}
bool
WaveReader::LoadFormatChunk(uint32_t aChunkSize)
{
uint32_t rate, channels, frameSize, sampleFormat;
char waveFormat[WAVE_FORMAT_CHUNK_SIZE];
const char* p = waveFormat;
// RIFF chunks are always word (two byte) aligned.
MOZ_ASSERT(mDecoder->GetResource()->Tell() % 2 == 0,
"LoadFormatChunk called with unaligned resource");
if (!ReadAll(waveFormat, sizeof(waveFormat))) {
return false;
}
static_assert(sizeof(uint16_t) +
sizeof(uint16_t) +
sizeof(uint32_t) +
4 +
sizeof(uint16_t) +
sizeof(uint16_t) <= sizeof(waveFormat),
"Reads would overflow waveFormat buffer.");
if (ReadUint16LE(&p) != WAVE_FORMAT_ENCODING_PCM) {
NS_WARNING("WAVE is not uncompressed PCM, compressed encodings are not supported");
return false;
}
channels = ReadUint16LE(&p);
rate = ReadUint32LE(&p);
// Skip over average bytes per second field.
p += 4;
frameSize = ReadUint16LE(&p);
sampleFormat = ReadUint16LE(&p);
// PCM encoded WAVEs are not expected to have an extended "format" chunk,
// but I have found WAVEs that have a extended "format" chunk with an
// extension size of 0 bytes. Be polite and handle this rather than
// considering the file invalid. This code skips any extension of the
// "format" chunk.
if (aChunkSize > WAVE_FORMAT_CHUNK_SIZE) {
char extLength[2];
const char* p = extLength;
if (!ReadAll(extLength, sizeof(extLength))) {
return false;
}
static_assert(sizeof(uint16_t) <= sizeof(extLength),
"Reads would overflow extLength buffer.");
uint16_t extra = ReadUint16LE(&p);
if (aChunkSize - (WAVE_FORMAT_CHUNK_SIZE + 2) != extra) {
NS_WARNING("Invalid extended format chunk size");
return false;
}
extra += extra % 2;
if (extra > 0) {
static_assert(UINT16_MAX + (UINT16_MAX % 2) < UINT_MAX / sizeof(char),
"chunkExtension array too large for iterator.");
nsAutoArrayPtr<char> chunkExtension(new char[extra]);
if (!ReadAll(chunkExtension.get(), extra)) {
return false;
}
}
}
// RIFF chunks are always word (two byte) aligned.
MOZ_ASSERT(mDecoder->GetResource()->Tell() % 2 == 0,
"LoadFormatChunk left resource unaligned");
// Make sure metadata is fairly sane. The rate check is fairly arbitrary,
// but the channels check is intentionally limited to mono or stereo
// when the media is intended for direct playback because that's what the
// audio backend currently supports.
unsigned int actualFrameSize = (sampleFormat == 8 ? 1 : 2) * channels;
if (rate < 100 || rate > 96000 ||
(((channels < 1 || channels > MAX_CHANNELS) ||
(frameSize != 1 && frameSize != 2 && frameSize != 4)) &&
!mIgnoreAudioOutputFormat) ||
(sampleFormat != 8 && sampleFormat != 16) ||
frameSize != actualFrameSize) {
NS_WARNING("Invalid WAVE metadata");
return false;
}
ReentrantMonitorAutoEnter monitor(mDecoder->GetReentrantMonitor());
mSampleRate = rate;
mChannels = channels;
mFrameSize = frameSize;
if (sampleFormat == 8) {
mSampleFormat = FORMAT_U8;
} else {
mSampleFormat = FORMAT_S16;
}
return true;
}
bool
WaveReader::LoadFormatChunk()
{
uint32_t fmtSize, rate, channels, frameSize, sampleFormat;
char waveFormat[WAVE_FORMAT_CHUNK_SIZE];
const char* p = waveFormat;
// RIFF chunks are always word (two byte) aligned.
NS_ABORT_IF_FALSE(mDecoder->GetResource()->Tell() % 2 == 0,
"LoadFormatChunk called with unaligned resource");
// The "format" chunk may not directly follow the "riff" chunk, so skip
// over any intermediate chunks.
if (!ScanForwardUntil(FRMT_CHUNK_MAGIC, &fmtSize)) {
return false;
}
if (!ReadAll(waveFormat, sizeof(waveFormat))) {
return false;
}
PR_STATIC_ASSERT(sizeof(uint16_t) +
sizeof(uint16_t) +
sizeof(uint32_t) +
4 +
sizeof(uint16_t) +
sizeof(uint16_t) <= sizeof(waveFormat));
if (ReadUint16LE(&p) != WAVE_FORMAT_ENCODING_PCM) {
NS_WARNING("WAVE is not uncompressed PCM, compressed encodings are not supported");
return false;
}
channels = ReadUint16LE(&p);
rate = ReadUint32LE(&p);
// Skip over average bytes per second field.
p += 4;
frameSize = ReadUint16LE(&p);
sampleFormat = ReadUint16LE(&p);
// PCM encoded WAVEs are not expected to have an extended "format" chunk,
// but I have found WAVEs that have a extended "format" chunk with an
// extension size of 0 bytes. Be polite and handle this rather than
// considering the file invalid. This code skips any extension of the
// "format" chunk.
if (fmtSize > WAVE_FORMAT_CHUNK_SIZE) {
char extLength[2];
const char* p = extLength;
if (!ReadAll(extLength, sizeof(extLength))) {
return false;
}
PR_STATIC_ASSERT(sizeof(uint16_t) <= sizeof(extLength));
uint16_t extra = ReadUint16LE(&p);
if (fmtSize - (WAVE_FORMAT_CHUNK_SIZE + 2) != extra) {
NS_WARNING("Invalid extended format chunk size");
return false;
}
extra += extra % 2;
if (extra > 0) {
PR_STATIC_ASSERT(UINT16_MAX + (UINT16_MAX % 2) < UINT_MAX / sizeof(char));
nsAutoArrayPtr<char> chunkExtension(new char[extra]);
if (!ReadAll(chunkExtension.get(), extra)) {
return false;
}
}
}
// RIFF chunks are always word (two byte) aligned.
NS_ABORT_IF_FALSE(mDecoder->GetResource()->Tell() % 2 == 0,
"LoadFormatChunk left resource unaligned");
// Make sure metadata is fairly sane. The rate check is fairly arbitrary,
// but the channels check is intentionally limited to mono or stereo
// because that's what the audio backend currently supports.
unsigned int actualFrameSize = sampleFormat == 8 ? 1 : 2 * channels;
if (rate < 100 || rate > 96000 ||
channels < 1 || channels > MAX_CHANNELS ||
(frameSize != 1 && frameSize != 2 && frameSize != 4) ||
(sampleFormat != 8 && sampleFormat != 16) ||
frameSize != actualFrameSize) {
NS_WARNING("Invalid WAVE metadata");
return false;
}
ReentrantMonitorAutoEnter monitor(mDecoder->GetReentrantMonitor());
mSampleRate = rate;
mChannels = channels;
mFrameSize = frameSize;
if (sampleFormat == 8) {
mSampleFormat = FORMAT_U8;
} else {
mSampleFormat = FORMAT_S16;
}
return true;
}
