C++ PacketReader::available方法代码示例

	void add(PacketReader& fragment) {
		string::size_type old = _pBuffer->size();
		_pBuffer->resize(old + fragment.available(),true);
		if(_pBuffer->size()>old)
			memcpy(_pBuffer->data()+old,fragment.current(),fragment.available());
		++(UInt16&)fragments;
	}

	void add(PacketReader& fragment) {
		string::size_type old = _buffer.size();
		_buffer.resize(old + (string::size_type)fragment.available());
		if(_buffer.size()>old)
			memcpy(&_buffer[old],fragment.current(),(size_t)fragment.available());
		++(UInt16&)fragments;
	}

bool WSSession::buildPacket(PacketReader& packet) {
	if (packet.available()<2)
		return false;
	UInt8 type = packet.read8() & 0x0F;
	UInt8 lengthByte = packet.read8();

	UInt32 size=lengthByte&0x7f;
	if (size==127) {
		if (packet.available()<8)
			return false;
		size = (UInt32)packet.read64();
	} else if (size==126) {
		if (packet.available()<2)
			return false;
		size = packet.read16();
	}

	if(lengthByte&0x80)
		size += 4;

	if (packet.available()<size)
		return false;

	packet.shrink(size);

	if (lengthByte & 0x80) {
		shared_ptr<WSUnmasking> pWSUnmasking(new WSUnmasking(invoker, packet.current(),packet.available(), type));
		decode<WSUnmasking>(pWSUnmasking);
	} else {
		packet.reset(packet.position()-1);
		*(UInt8*)packet.current() = type;
	}
	return true;
}

void ServerConnection::packetHandler(PacketReader& packet) {

	UInt8 marker = packet.read8();
	if(marker!=0x0b) {
		ERROR("ServerConnection with an unknown %u marker, it should be 0x0b",marker);
		return;
	}

	packet.next(2);
	UInt8 id = packet.read8();
	switch(id) {
		case 0x71: {
			packet.next(2);
			string tag;
			packet.readString8(tag);
			map<string,P2PHandshakerAddress>::iterator it = _p2pHandshakers.find(tag);
			if(it==_p2pHandshakers.end()) {
				ERROR("Unknown ServerConnection tag %s on P2P handshake",tag.c_str());
				break;
			}

			(SocketAddress&)_handshake.peer.address = it->second;
			packet.reset(0);
			PacketWriter writer(packet.current(),packet.available()+16); // +16 for futur 0xFFFF padding
			writer.clear(packet.available());
			_handshake.send(writer);
			_p2pHandshakers.erase(it);

			break;
		}
		case 0x40: {
			if(!_connected) {
				// Edge hello response
				_connected=true;
				return;
			}
			// Edge keepalive
			PacketWriter& packet(writer());
			packet.write8(0x41);
			packet.write16(0);
			flush();
			INFO("Keepalive RTMFP server");
			break;
		}
		case 0x45: {
			// Server is death!
			(bool&)died=true;
			break;
		}
		default:
			ERROR("Unkown ServerConnection packet id %u",id);
	}


}

Message::Type Flow::unpack(PacketReader& reader) {
	if(reader.available()==0)
		return Message::EMPTY;
	Message::Type type = (Message::Type)reader.read8();
	switch(type) {
		// amf content
		case 0x11:
			reader.next(1);
		case Message::AMF_WITH_HANDLER:
			reader.next(4);
			return Message::AMF_WITH_HANDLER;
		case Message::AMF:
			reader.next(5);
		case Message::AUDIO:
		case Message::VIDEO:
			break;
		// raw data
		case 0x04:
			reader.next(4);
		case 0x01:
			break;
		default:
			ERROR("Unpacking type '%02x' unknown",type);
			break;
	}
	return type;
}

AMF::ContentType RTMFPFlow::unpack(PacketReader& packet,UInt32& time) {
	if(packet.available()==0)
		return AMF::EMPTY;
	AMF::ContentType type = (AMF::ContentType)packet.read8();
	switch(type) {
		// amf content
		case AMF::INVOCATION_AMF3:
			packet.next(1);
		case AMF::INVOCATION:
			packet.next(4);
			return AMF::INVOCATION;
		case AMF::AUDIO:
		case AMF::VIDEO:
			time = packet.read32();
			break;
		case AMF::DATA:
			packet.next(1);
		case AMF::RAW:
			packet.next(4);
		case AMF::CHUNKSIZE:
			break;
		default:
			ERROR("Unpacking type '",Format<UInt8>("%02x",(UInt8)type),"' unknown");
			break;
	}
	return type;
}

bool RTMFP::Decode(Exception& ex,RTMFPEngine& aesDecrypt,PacketReader& packet) {
	// Decrypt
	aesDecrypt.process(packet.current(),(UInt8*)packet.current(),packet.available());
	bool result = ReadCRC(packet);
	if (!result)
		ex.set(Exception::CRYPTO, "Bad RTMFP CRC sum computing");
	return result;
}

bool RTMFP::Decode(AESEngine& aesDecrypt,PacketReader& packet) {
	// Decrypt
	aesDecrypt.process(packet.current(),packet.current(),packet.available());

	// Check the first 2 CRC bytes 
	packet.reset(4);
	UInt16 sum = packet.read16();
	return (sum == CheckSum(packet));
}

void Listener::pushDataPacket(const string& name,PacketReader& packet) {
	// TODO create _dataWriter ??
	if(_unbuffered) {
		UInt16 offset = name.size()+9;
		if(packet.position()>=offset) {
			packet.reset(packet.position()-offset);
			_writer.writeUnbufferedMessage(packet.current(),packet.available());
			return;
		}
		WARN("Written unbuffered impossible, it requires %u head bytes available on PacketReader given",offset);
	}
	StreamCopier::copyStream(packet.stream(),_writer.writeAMFPacket(name).writer.stream());
}

bool WSWriter::writeMedia(MediaType type,UInt32 time,PacketReader& packet,Parameters& properties) {
	if(state()==CLOSED)
		return true;
	switch(type) {
		case START:
			writeInvocation("__publishing").writeString(string((const char*)packet.current(),packet.available()));
			break;
		case STOP:
			writeInvocation("__unpublishing").writeString(string((const char*)packet.current(),packet.available()));
			break;
		case DATA: {
			JSONWriter& writer = newDataWriter();
			writer.packet.write8('[');
			writer.packet.writeRaw(packet.current(),packet.available());
			writer.packet.write8(']');
			break;
		}
		case INIT:
			break;
		default:
			return Writer::writeMedia(type,time,packet,properties);
	}
	return true;
}

	void write(UInt32 time,PacketReader& data,bool unbuffered) {
	//	if(_type==0x08)
	//		time=0;
	/*	if(_type==0x09)
			TRACE("Video timestamp : %u",_time)
		else
			TRACE("Audio timestamp : %u",_time);*/
		if(unbuffered) {
			if(data.position()>=5) {
				data.reset(data.position()-5);
				PacketWriter writer(data.current(),5);
				writer.write8(_type);
				writer.write32(time);
				writeUnbufferedMessage(data.current(),data.available(),data.current(),5);
				return;
			}
			WARN("Written unbuffered impossible, it requires 5 head bytes available on PacketReader given");
		}
		BinaryWriter& out = writeRawMessage(true);
		out.write8(_type);
		out.write32(time);
		StreamCopier::copyStream(data.stream(),out.stream());

	}

void Middle::targetPacketHandler(PacketReader& packet) {

	if(_firstResponse)
		((Timestamp&)peer.lastReceptionTime).update(); // To emulate a long ping corresponding, otherwise client send multiple times each packet
	_firstResponse = false;

	UInt8 marker = packet.read8();
	
	_timeSent = packet.read16(); // time

	UInt16 timeEcho(0);
	if((marker|0xF0) == 0xFE)
		timeEcho = packet.read16(); // time echo

	PacketWriter& packetOut = writer();

	int pos = packetOut.position();

	UInt8 type = packet.available()>0 ? packet.read8() : 0xFF;

	UInt64 idFlow,stage;
	UInt8 nbPeerSent = 0;

	while(type!=0xFF) {
		int posType = packetOut.position();
		packetOut.write8(type);

		UInt16 size = packet.read16();
		PacketReader content(packet.current(),size);packetOut.write16(size);

		if(type==0x10 || type==0x11) {
			UInt8 flag = content.read8();packetOut.write8(flag);
			if(type==0x10) {
				idFlow = content.read7BitLongValue();packetOut.write7BitLongValue(idFlow);
				stage = content.read7BitLongValue();packetOut.write7BitLongValue(stage);
				packetOut.write7BitLongValue(content.read7BitLongValue());
			} else
				++stage;
			
			if(!(flag&MESSAGE_WITH_BEFOREPART)) {

				if(flag&MESSAGE_HEADER) {
					UInt8 len = content.read8(); packetOut.write8(len);
					while(len!=0) {
						packetOut.writeRaw(content.current(),len);
						content.next(len);
						len = content.read8(); packetOut.write8(len);
					}
				}

				UInt8 flagType = content.read8(); packetOut.write8(flagType);
				if(flagType==0x09) {
					UInt32 time = content.read32(); packetOut.write32(time);
					TRACE("Timestamp/Flag video : %u/%2x",time,*content.current());
				} else if(flagType==0x08) {
					UInt32 time = content.read32(); packetOut.write32(time);
					TRACE("Timestamp/Flag audio : %u/%2x",time,*content.current());
				} else if(flagType==0x04) {
					packetOut.write32(content.read32());
					UInt16 a = content.read16();packetOut.write16(a);
					UInt32 b = content.read32(); packetOut.write32(b);
					if(content.available()>0) {
						UInt32 c = content.read32(); packetOut.write32(c);
						if(a!=0x22) {
							DEBUG("Raw %llu : %.2x %u %u",idFlow,a,b,c)
						} else {
							TRACE("Bound %llu : %.2x %u %u",idFlow,a,b,c);
						}
					} else
						DEBUG("Raw %llu : %.2x %u",idFlow,a,b)
					
				/*	if(a==0x1F) {
						packetOut.reset(posType);
						content.next(content.available());
					}*/
				}

void Middle::packetHandler(PacketReader& packet) {
	if(!_pMiddleAesEncrypt)
		manage(); // to wait the target handshake response

	// Middle to target
	PacketWriter& request = requester();

	UInt8 marker = packet.read8();
	request << marker;

	request << packet.read16();

	if((marker|0xF0) == 0xFD)
		request.write16(packet.read16()); // time echo

	int pos = request.position();

	UInt8 type = packet.available()>0 ? packet.read8() : 0xFF;
	while(type!=0xFF) {
		UInt16 size = packet.read16();
		PacketReader content(packet.current(),size);

		PacketWriter out(request.begin()+request.position(),request.available()); // 3 for future type and size
		out.clear(3);

		if(type==0x10) {

			out.write8(content.read8());
			UInt64 idFlow = content.read7BitLongValue();out.write7BitLongValue(idFlow);
			UInt64 stage = content.read7BitLongValue();out.write7BitLongValue(stage);

			if(idFlow==0x02 && stage==0x01) {
				if(!_isPeer) {
				
					/// Replace NetConnection infos

					out.writeRaw(content.current(),14);content.next(14);

					// first string
					string tmp;
					content.readString16(tmp);out.writeString16(tmp);

					AMFWriter writer(out);
					writer.amf0Preference=true;
					AMFReader reader(content);
					writer.writeNumber(reader.readNumber()); // double
					
					AMFSimpleObject obj;
					reader.readSimpleObject(obj);
					
					/// Replace tcUrl
					if(obj.has("tcUrl"))
						obj.setString("tcUrl",_queryUrl);
					
					writer.writeSimpleObject(obj);

				} else {

					out.writeRaw(content.current(),3);content.next(3);
					UInt16 netGroupHeader = content.read16();out.write16(netGroupHeader);
					if(netGroupHeader==0x4752) {

						map<string,string>::const_iterator it = peer.properties.find("groupspec");
						if(it!=peer.properties.end()) {
							out.writeRaw(content.current(),71);content.next(71);
							UInt8 result1[AES_KEY_SIZE];
							UInt8 result2[AES_KEY_SIZE];
							HMAC(EVP_sha256(),&_sharedSecret[0],_sharedSecret.size(),&_targetNonce[0],_targetNonce.size(),result1,NULL);
							HMAC(EVP_sha256(),it->second.c_str(),it->second.size(),result1,AES_KEY_SIZE,result2,NULL);
							out.writeRaw(result2,AES_KEY_SIZE);content.next(AES_KEY_SIZE);
							out.writeRaw(content.current(),4);content.next(4);
							out.writeRaw(_target.peerId,ID_SIZE);content.next(ID_SIZE);
						} else
							WARN("No groupspec client property indicated to make working the 'man-in-the-middle' mode between peers in a NetGroup case");
						
					}
				}
			}

		}  else if(type == 0x4C) {
			 kill();
			 return;
		}  else if(type == 0x51) {
			//printf("%s\n",Util::FormatHex(content.current(),content.available()).c_str());
		}
		out.writeRaw(content.current(),content.available());

		packet.next(size);

		if(out.length()>=3) {
			request<<type;
			size = out.length()-3;
			request.write16(size);request.next(size);
		}


		type = packet.available()>0 ? packet.read8() : 0xFF;
	}

	if(request.length()>pos)
//.........这里部分代码省略.........

	Fragment(PacketReader& data,UInt8 flags) : flags(flags),Buffer<UInt8>(data.available()) {
		data.readRaw(begin(),size());
	}

bool RTMFP::Decode(AESEngine& aesDecrypt,PacketReader& packet) {
	// Decrypt
	aesDecrypt.process(packet.current(),packet.current(),packet.available());
	return ReadCRC(packet);
}