NS_IMETHODIMP
nsBinaryOutputStream::WriteCompoundObject(nsISupports* aObject,
const nsIID& aIID,
PRBool aIsStrongRef)
{
// Can't deal with weak refs
NS_ENSURE_TRUE(aIsStrongRef, NS_ERROR_UNEXPECTED);
nsCOMPtr<nsIClassInfo> classInfo = do_QueryInterface(aObject);
NS_ENSURE_TRUE(classInfo, NS_ERROR_NOT_AVAILABLE);
nsCOMPtr<nsISerializable> serializable = do_QueryInterface(aObject);
NS_ENSURE_TRUE(serializable, NS_ERROR_NOT_AVAILABLE);
nsCID cid;
classInfo->GetClassIDNoAlloc(&cid);
nsresult rv = WriteID(cid);
NS_ENSURE_SUCCESS(rv, rv);
rv = WriteID(aIID);
NS_ENSURE_SUCCESS(rv, rv);
return serializable->Write(this);
}
uint64 WriteVoidElement(IMkvWriter* writer, uint64 size) {
if (!writer)
return false;
// Subtract one for the void ID and the coded size.
uint64 void_entry_size = size - 1 - GetCodedUIntSize(size-1);
uint64 void_size = EbmlMasterElementSize(kMkvVoid, void_entry_size) +
void_entry_size;
if (void_size != size)
return 0;
const int64 payload_position = writer->Position();
if (payload_position < 0)
return 0;
if (WriteID(writer, kMkvVoid))
return 0;
if (WriteUInt(writer, void_entry_size))
return 0;
const uint8 value = 0;
for (int32 i = 0; i < static_cast<int32>(void_entry_size); ++i) {
if (writer->Write(&value, 1))
return 0;
}
const int64 stop_position = writer->Position();
if (stop_position < 0 ||
stop_position - payload_position != static_cast<int64>(void_size))
return 0;
return void_size;
}
// Writes a WebM BlockGroup with DiscardPadding. The structure is as follows:
// Indentation shows sub-levels
// BlockGroup
// Block
// Data
// DiscardPadding
uint64 WriteBlockWithDiscardPadding(IMkvWriter* writer,
const uint8* data,
uint64 length,
int64 discard_padding,
uint64 track_number,
int64 timecode,
uint64 is_key) {
if (!data || length < 1 || discard_padding <= 0)
return 0;
const uint64 block_payload_size = 4 + length;
const uint64 block_elem_size = EbmlMasterElementSize(kMkvBlock,
block_payload_size) +
block_payload_size;
const uint64 discard_padding_elem_size = EbmlElementSize(kMkvDiscardPadding,
discard_padding);
const uint64 block_group_payload_size = block_elem_size +
discard_padding_elem_size;
const uint64 block_group_elem_size = EbmlMasterElementSize(
kMkvBlockGroup,
block_group_payload_size) +
block_group_payload_size;
if (!WriteEbmlMasterElement(writer, kMkvBlockGroup,
block_group_payload_size))
return 0;
if (!WriteEbmlMasterElement(writer, kMkvBlock, block_payload_size))
return 0;
if (WriteUInt(writer, track_number))
return 0;
if (SerializeInt(writer, timecode, 2))
return 0;
uint64 flags = 0;
if (is_key)
flags |= 0x80;
if (SerializeInt(writer, flags, 1))
return 0;
if (writer->Write(data, static_cast<uint32>(length)))
return 0;
if (WriteID(writer, kMkvDiscardPadding))
return 0;
const uint64 size = GetUIntSize(discard_padding);
if (WriteUInt(writer, size))
return false;
if (SerializeInt(writer, discard_padding, static_cast<int32>(size)))
return false;
return block_group_elem_size;
}
void GoBlock::Write(std::ostream& stream) const
{
WriteID(stream);
stream << '\n'
<< SgWritePointSet(Stones(), "Stones: ")
<< "\nhealthy: " << Healthy().Length()
<< "\nisSafe: " << SgWriteBoolean(IsSafe())
<< "\nhas1Eye: " << SgWriteBoolean(Has1Eye())
<< "\n";
}
uint64 WriteSimpleBlock(IMkvWriter* writer,
const uint8* data,
uint64 length,
uint64 track_number,
int64 timecode,
uint64 is_key) {
if (!writer)
return false;
if (!data || length < 1)
return false;
// Here we only permit track number values to be no greater than
// 126, which the largest value we can store having a Matroska
// integer representation of only 1 byte.
if (track_number < 1 || track_number > 126)
return false;
// Technically the timestamp for a block can be less than the
// timestamp for the cluster itself (remember that block timestamp
// is a signed, 16-bit integer). However, as a simplification we
// only permit non-negative cluster-relative timestamps for blocks.
if (timecode < 0 || timecode > kMaxBlockTimecode)
return false;
if (WriteID(writer, kMkvSimpleBlock))
return 0;
const int32 size = static_cast<int32>(length) + 4;
if (WriteUInt(writer, size))
return 0;
if (WriteUInt(writer, static_cast<uint64>(track_number)))
return 0;
if (SerializeInt(writer, timecode, 2))
return 0;
uint64 flags = 0;
if (is_key)
flags |= 0x80;
if (SerializeInt(writer, flags, 1))
return 0;
if (writer->Write(data, static_cast<uint32>(length)))
return 0;
const uint64 element_size =
GetUIntSize(kMkvSimpleBlock) + GetCodedUIntSize(size) + 4 + length;
return element_size;
}
bool WriteEbmlMasterElement(IMkvWriter* writer, uint64 type, uint64 size) {
if (!writer)
return false;
if (WriteID(writer, type))
return false;
if (WriteUInt(writer, size))
return false;
return true;
}
NS_IMETHODIMP
nsBinaryOutputStream::WriteCompoundObject(nsISupports* aObject,
const nsIID& aIID,
bool aIsStrongRef)
{
nsCOMPtr<nsIClassInfo> classInfo = do_QueryInterface(aObject);
nsCOMPtr<nsISerializable> serializable = do_QueryInterface(aObject);
// Can't deal with weak refs
if (NS_WARN_IF(!aIsStrongRef))
return NS_ERROR_UNEXPECTED;
if (NS_WARN_IF(!classInfo) || NS_WARN_IF(!serializable))
return NS_ERROR_NOT_AVAILABLE;
nsCID cid;
nsresult rv = classInfo->GetClassIDNoAlloc(&cid);
if (NS_SUCCEEDED(rv)) {
rv = WriteID(cid);
} else {
nsCID *cidptr = nullptr;
rv = classInfo->GetClassID(&cidptr);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
rv = WriteID(*cidptr);
NS_Free(cidptr);
}
if (NS_WARN_IF(NS_FAILED(rv)))
return rv;
rv = WriteID(aIID);
if (NS_WARN_IF(NS_FAILED(rv)))
return rv;
return serializable->Write(this);
}
bool WriteEbmlElement(IMkvWriter* writer, uint64 type, float value) {
if (!writer)
return false;
if (WriteID(writer, type))
return false;
if (WriteUInt(writer, 4))
return false;
if (SerializeFloat(writer, value))
return false;
return true;
}
bool WriteEbmlDateElement(IMkvWriter* writer, uint64 type, int64 value) {
if (!writer)
return false;
if (WriteID(writer, type))
return false;
if (WriteUInt(writer, kDateElementSize))
return false;
if (SerializeInt(writer, value, kDateElementSize))
return false;
return true;
}
bool WriteEbmlElement(IMkvWriter* writer, uint64 type, const char* value) {
if (!writer || !value)
return false;
if (WriteID(writer, type))
return false;
const int32 length = strlen(value);
if (WriteUInt(writer, length))
return false;
if (writer->Write(value, length))
return false;
return true;
}
bool WriteEbmlElement(IMkvWriter* writer, uint64 type, uint64 value) {
if (!writer)
return false;
if (WriteID(writer, type))
return false;
const uint64 size = GetUIntSize(value);
if (WriteUInt(writer, size))
return false;
if (SerializeInt(writer, value, static_cast<int32>(size)))
return false;
return true;
}
bool WriteEbmlElement(IMkvWriter* writer, uint64 type, const uint8* value,
uint64 size) {
if (!writer || !value || size < 1)
return false;
if (WriteID(writer, type))
return false;
if (WriteUInt(writer, size))
return false;
if (writer->Write(value, static_cast<uint32>(size)))
return false;
return true;
}
// We must write the metadata (key)frame as a BlockGroup element,
// because we need to specify a duration for the frame. The
// BlockGroup element comprises the frame itself and its duration,
// and is laid out as follows:
//
// BlockGroup tag
// BlockGroup size
// Block tag
// Block size
// (the frame is the block payload)
// Duration tag
// Duration size
// (duration payload)
//
uint64 WriteMetadataBlock(IMkvWriter* writer,
const uint8* data,
uint64 length,
uint64 track_number,
int64 timecode,
uint64 duration) {
// We don't backtrack when writing to the stream, so we must
// pre-compute the BlockGroup size, by summing the sizes of each
// sub-element (the block and the duration).
// We use a single byte for the track number of the block, which
// means the block header is exactly 4 bytes.
// TODO(matthewjheaney): use EbmlMasterElementSize and WriteEbmlMasterElement
const uint64 block_payload_size = 4 + length;
const int32 block_size = GetCodedUIntSize(block_payload_size);
const uint64 block_elem_size = 1 + block_size + block_payload_size;
const int32 duration_payload_size = GetUIntSize(duration);
const int32 duration_size = GetCodedUIntSize(duration_payload_size);
const uint64 duration_elem_size = 1 + duration_size + duration_payload_size;
const uint64 blockg_payload_size = block_elem_size + duration_elem_size;
const int32 blockg_size = GetCodedUIntSize(blockg_payload_size);
const uint64 blockg_elem_size = 1 + blockg_size + blockg_payload_size;
if (WriteID(writer, kMkvBlockGroup)) // 1-byte ID size
return 0;
if (WriteUInt(writer, blockg_payload_size))
return 0;
// Write Block element
if (WriteID(writer, kMkvBlock)) // 1-byte ID size
return 0;
if (WriteUInt(writer, block_payload_size))
return 0;
// Byte 1 of 4
if (WriteUInt(writer, track_number))
return 0;
// Bytes 2 & 3 of 4
if (SerializeInt(writer, timecode, 2))
return 0;
// Byte 4 of 4
const uint64 flags = 0;
if (SerializeInt(writer, flags, 1))
return 0;
// Now write the actual frame (of metadata)
if (writer->Write(data, static_cast<uint32>(length)))
return 0;
// Write Duration element
if (WriteID(writer, kMkvBlockDuration)) // 1-byte ID size
return 0;
if (WriteUInt(writer, duration_payload_size))
return 0;
if (SerializeInt(writer, duration, duration_payload_size))
return 0;
// Note that we don't write a reference time as part of the block
// group; no reference time(s) indicates that this block is a
// keyframe. (Unlike the case for a SimpleBlock element, the header
// bits of the Block sub-element of a BlockGroup element do not
// indicate keyframe status. The keyframe status is inferred from
// the absence of reference time sub-elements.)
return blockg_elem_size;
}
