/**
* Continues a read from the provided {@code source} into a given {@code target}. It's assumed
* that the data should be written into {@code target} starting from an offset of zero.
*
* @param source The source from which to read.
* @param target The target into which data is to be read, or {@code null} to skip.
* @param targetLength The target length of the read.
* @return Whether the target length has been reached.
*/
private boolean continueRead(ParsableByteArray source, byte[] target, int targetLength) {
int bytesToRead = Math.min(source.bytesLeft(), targetLength - bytesRead);
if (bytesToRead <= 0) {
return true;
} else if (target == null) {
source.skip(bytesToRead);
} else {
source.readBytes(target, bytesRead, bytesToRead);
}
bytesRead += bytesToRead;
return bytesRead == targetLength;
}
private static void parseSenc(ParsableByteArray senc, int offset, TrackFragment out)
throws ParserException {
senc.setPosition(Atom.HEADER_SIZE + offset);
int fullAtom = senc.readInt();
int flags = Atom.parseFullAtomFlags(fullAtom);
if ((flags & 0x01 /* override_track_encryption_box_parameters */) != 0) {
// TODO: Implement this.
throw new ParserException("Overriding TrackEncryptionBox parameters is unsupported.");
}
boolean subsampleEncryption = (flags & 0x02 /* use_subsample_encryption */) != 0;
int sampleCount = senc.readUnsignedIntToInt();
if (sampleCount != out.length) {
throw new ParserException("Length mismatch: " + sampleCount + ", " + out.length);
}
Arrays.fill(out.sampleHasSubsampleEncryptionTable, 0, sampleCount, subsampleEncryption);
out.initEncryptionData(senc.bytesLeft());
out.fillEncryptionData(senc);
}
@Override
public void consume(ParsableByteArray data) {
if (!writingSample) {
return;
}
int bytesAvailable = data.bytesLeft();
if (sampleBytesRead < ID3_HEADER_SIZE) {
// We're still reading the ID3 header.
int headerBytesAvailable = Math.min(bytesAvailable, ID3_HEADER_SIZE - sampleBytesRead);
System.arraycopy(
data.data, data.getPosition(), id3Header.data, sampleBytesRead, headerBytesAvailable);
if (sampleBytesRead + headerBytesAvailable == ID3_HEADER_SIZE) {
// We've finished reading the ID3 header. Extract the sample size.
id3Header.setPosition(6); // 'ID3' (3) + version (2) + flags (1)
sampleSize = ID3_HEADER_SIZE + id3Header.readSynchSafeInt();
}
}
// Write data to the output.
output.sampleData(data, bytesAvailable);
sampleBytesRead += bytesAvailable;
}
@Override
public void consume(ParsableByteArray data, boolean payloadUnitStartIndicator) {
if (payloadUnitStartIndicator) {
switch (state) {
case STATE_FINDING_HEADER:
case STATE_READING_HEADER:
// Expected.
break;
case STATE_READING_HEADER_EXTENSION:
Log.w(TAG, "Unexpected start indicator reading extended header");
break;
case STATE_READING_BODY:
// If payloadSize == -1 then the length of the previous packet was unspecified, and so
// we only know that it's finished now that we've seen the start of the next one. This
// is expected. If payloadSize != -1, then the length of the previous packet was known,
// but we didn't receive that amount of data. This is not expected.
if (payloadSize != -1) {
Log.w(TAG, "Unexpected start indicator: expected " + payloadSize + " more bytes");
}
// Either way, if the body was started, notify the reader that it has now finished.
if (bodyStarted) {
pesPayloadReader.packetFinished();
}
break;
}
setState(STATE_READING_HEADER);
}
while (data.bytesLeft() > 0) {
switch (state) {
case STATE_FINDING_HEADER:
data.skip(data.bytesLeft());
break;
case STATE_READING_HEADER:
if (continueRead(data, pesScratch.getData(), HEADER_SIZE)) {
setState(parseHeader() ? STATE_READING_HEADER_EXTENSION : STATE_FINDING_HEADER);
}
break;
case STATE_READING_HEADER_EXTENSION:
int readLength = Math.min(MAX_HEADER_EXTENSION_SIZE, extendedHeaderLength);
// Read as much of the extended header as we're interested in, and skip the rest.
if (continueRead(data, pesScratch.getData(), readLength)
&& continueRead(data, null, extendedHeaderLength)) {
parseHeaderExtension();
bodyStarted = false;
setState(STATE_READING_BODY);
}
break;
case STATE_READING_BODY:
readLength = data.bytesLeft();
int padding = payloadSize == -1 ? 0 : readLength - payloadSize;
if (padding > 0) {
readLength -= padding;
data.setLimit(data.getPosition() + readLength);
}
pesPayloadReader.consume(data, timeUs, !bodyStarted);
bodyStarted = true;
if (payloadSize != -1) {
payloadSize -= readLength;
if (payloadSize == 0) {
pesPayloadReader.packetFinished();
setState(STATE_READING_HEADER);
}
}
break;
}
}
}