bool LineBasedFrameDecoder::decode(Context* ctx,
IOBufQueue& buf,
std::unique_ptr<IOBuf>& result,
size_t&) {
int64_t eol = findEndOfLine(buf);
if (!discarding_) {
if (eol >= 0) {
Cursor c(buf.front());
c += eol;
auto delimLength = c.read<char>() == '\r' ? 2 : 1;
if (eol > maxLength_) {
buf.split(eol + delimLength);
fail(ctx, folly::to<std::string>(eol));
return false;
}
std::unique_ptr<folly::IOBuf> frame;
if (stripDelimiter_) {
frame = buf.split(eol);
buf.trimStart(delimLength);
} else {
frame = buf.split(eol + delimLength);
}
result = std::move(frame);
return true;
} else {
auto len = buf.chainLength();
if (len > maxLength_) {
discardedBytes_ = len;
buf.trimStart(len);
discarding_ = true;
fail(ctx, "over " + folly::to<std::string>(len));
}
return false;
}
} else {
if (eol >= 0) {
Cursor c(buf.front());
c += eol;
auto delimLength = c.read<char>() == '\r' ? 2 : 1;
buf.trimStart(eol + delimLength);
discardedBytes_ = 0;
discarding_ = false;
} else {
discardedBytes_ = buf.chainLength();
buf.move();
}
return false;
}
}
int64_t LineBasedFrameDecoder::findEndOfLine(IOBufQueue& buf) {
Cursor c(buf.front());
for (uint32_t i = 0; i < maxLength_ && i < buf.chainLength(); i++) {
auto b = c.read<char>();
if (b == '\n' && terminatorType_ != TerminatorType::CARRIAGENEWLINE) {
return i;
} else if (terminatorType_ != TerminatorType::NEWLINE &&
b == '\r' && !c.isAtEnd() && c.read<char>() == '\n') {
return i;
}
}
return -1;
}
uint64_t LengthFieldBasedFrameDecoder::getUnadjustedFrameLength(
IOBufQueue& buf, int offset, int length, bool networkByteOrder) {
folly::io::Cursor c(buf.front());
uint64_t frameLength;
c.skip(offset);
switch(length) {
case 1:{
if (networkByteOrder) {
frameLength = c.readBE<uint8_t>();
} else {
frameLength = c.readLE<uint8_t>();
}
break;
}
case 2:{
if (networkByteOrder) {
frameLength = c.readBE<uint16_t>();
} else {
frameLength = c.readLE<uint16_t>();
}
break;
}
case 4:{
if (networkByteOrder) {
frameLength = c.readBE<uint32_t>();
} else {
frameLength = c.readLE<uint32_t>();
}
break;
}
case 8:{
if (networkByteOrder) {
frameLength = c.readBE<uint64_t>();
} else {
frameLength = c.readLE<uint64_t>();
}
break;
}
}
return frameLength;
}