git-svn-id: svn://db.shs.com.ru/libs@622 a8b55f48-bf90-11e4-a774-851b48703e85

qad/utils/chunkstream.cpp

@@ -23,6 +23,32 @@ void ChunkStream::setSource(QDataStream & str) {
 }
 
 
+int ChunkStream::read() {
+	switch (version_) {
+	case Version_1:
+		stream_ >> last_id >> last_data;
+		break;
+	case Version_2:
+		last_id = readVInt(stream_);
+		last_data.resize(readVInt(stream_));
+		//piCout << last_id << last_data.size();
+		stream_.readRawData(last_data.data(), last_data.size());
+		break;
+	default: break;
+	}
+	return last_id;
+}
+
+
+void ChunkStream::readAll() {
+	data_map.clear();
+	while (!atEnd()) {
+		read();
+		data_map[last_id] = last_data;
+	}
+}
+
+
 ChunkStream::~ChunkStream() {
 
 }
@@ -35,4 +61,53 @@ void ChunkStream::_init() {
 	buffer.setBuffer(data_);
 	buffer.open(QIODevice::ReadWrite);
 	stream_.setDevice(&buffer);
+	if (!data_->isEmpty()) {
+		uchar v = data_->at(0);
+		if ((v & 0x80) == 0x80) {
+			v &= 0x7f;
+			switch (v) {
+			case 2:  version_ = (uchar)Version_2; stream_.skipRawData(1); break;
+			default: break;
+			}
+		} else
+			version_ = Version_1;
+	}
+}
+
+
+uint ChunkStream::readVInt(QDataStream & s) {
+	if (s.atEnd()) return 0;
+	uchar bytes[4]; s >> bytes[0];
+	uchar abc = 0;
+	for (abc = 0; abc < 3; ++abc) {
+		uchar mask = (0x80 >> abc);
+		if ((bytes[0] & mask) == mask) {
+			//if (s.isEmpty()) return 0;
+			bytes[0] &= (mask - 1);
+			s >> bytes[abc + 1];
+		} else break;
+	}
+	uint ret = 0;
+	for (int i = 0; i <= abc; ++i) {
+		ret += (bytes[i] << (8 * ((int)abc - i)));
+	}
+	return ret;
+}
+
+
+void ChunkStream::writeVInt(QDataStream & s, uint val) {
+	if (val > 0xfffffff) return;
+	if (val <= 0x7f) {
+		s << uchar(val);
+		return;
+	}
+	if (val <= 0x3fff) {
+		s << uchar((val >> 8) | 0x80) << uchar(val & 0xff);
+		return;
+	}
+	if (val <= 0x1fffff) {
+		s << uchar((val >> 16) | 0xc0) << uchar((val >> 8) & 0xff) << uchar(val & 0xff);
+		return;
+	}
+	s << uchar((val >> 24) | 0xe0) << uchar((val >> 16) & 0xff) << uchar((val >> 8) & 0xff) << uchar(val & 0xff);
 }

qad/utils/chunkstream.h

@@ -4,14 +4,20 @@
 #include <QDataStream>
 #include <QBuffer>
 #include <QByteArray>
+#include <QMap>
 
 
 class ChunkStream
 {
 public:
-	ChunkStream(const QByteArray & data) {setSource(data);}
-	ChunkStream(QDataStream & str) {setSource(str);}
-	ChunkStream(QByteArray * data = 0) {setSource(data);}
+	enum Version {
+		Version_1 /*! First, old version */,
+		Version_2 /*! Second, more optimized version */ = 2,
+	};
+	ChunkStream(const QByteArray & data): version_(Version_2) {setSource(data);}
+	ChunkStream(QDataStream & str): version_(Version_2) {setSource(str);}
+	ChunkStream(QByteArray * data = 0, Version v = Version_2): version_(v) {setSource(data);}
+	ChunkStream(Version v): version_(v) {setSource(0);}
 	~ChunkStream();
 
 	template <typename T>
@@ -30,21 +36,38 @@ public:
 	QDataStream & dataStream() {return stream_;}
 	QByteArray data() const {return tmp_data;}
 	bool atEnd() const {return stream_.atEnd();}
+	Version version() const {return (Version)version_;}
 
-	int read() {stream_ >> last_id >> last_data; return last_id;}
+	int read();
+	void readAll();
 	int getID() {return last_id;}
 	template <typename T>
 	T getData() const {T ret; QDataStream s(last_data); s.setVersion(QDataStream::Qt_4_8); s >> ret; return ret;}
 	template <typename T>
 	void get(T & v) const {v = getData<T>();}
+	template <typename T>
+	const ChunkStream & get(int id, T & v) const {
+		QByteArray ba = data_map.value(id);
+		if (!ba.isEmpty()) {
+			QDataStream s(ba); s.setVersion(QDataStream::Qt_4_8);
+			s >> v;
+		}
+		return *this;
+	}
 private:
 	void _init();
 
+	static uint readVInt(QDataStream & s);
+	static void writeVInt(QDataStream & s, uint val);
+
 	int last_id;
+	uchar version_;
 	QByteArray * data_, last_data, tmp_data;
 	QBuffer buffer;
 	QDataStream stream_;
+	QMap<int, QByteArray> data_map;
 
+	template <typename T> friend ChunkStream & operator <<(ChunkStream & s, const ChunkStream::Chunk<T> & c);
 };
 
 template <typename T>
@@ -53,7 +76,19 @@ ChunkStream & operator <<(ChunkStream & s, const ChunkStream::Chunk<T> & c) {
 	QDataStream bas(&ba, QIODevice::WriteOnly);
 	bas.setVersion(QDataStream::Qt_4_8);
 	bas << c.data;
-	s.dataStream() << c.id << ba;
+	switch (s.version_) {
+	case ChunkStream::Version_1:
+		s.stream_ << c.id << ba;
+		break;
+	case ChunkStream::Version_2:
+		if (s.data_->isEmpty())
+			s.stream_ << uchar(uchar(s.version_) | 0x80);
+		ChunkStream::writeVInt(s.stream_, c.id);
+		ChunkStream::writeVInt(s.stream_, ba.size());
+		s.stream_.writeRawData(ba.data(), ba.size());
+		break;
+	default: break;
+	}
 	return s;
 }