func (hr *headerReader) read() (h http.Header, err error) {
var count uint32
if hr.decompressor == nil {
hr.decompressor, err = zlib.NewReaderDict(&hr.source, headerDictionary)
if err != nil {
return
}
}
err = binary.Read(hr.decompressor, binary.BigEndian, &count)
if err != nil {
return
}
h = make(http.Header, int(count))
for i := 0; i < int(count); i++ {
var name, value string
name, err = readHeaderString(hr.decompressor)
if err != nil {
return
}
value, err = readHeaderString(hr.decompressor)
if err != nil {
return
}
valueList := strings.Split(string(value), "\x00")
for _, v := range valueList {
h.Add(name, v)
}
}
return
}
//进行zlib解压缩
func DoZlibUnCompress(compressSrc []byte) ([]byte, error) {
b := bytes.NewReader(compressSrc)
var out bytes.Buffer
r, err := zlib.NewReaderDict(b, dict)
if err != nil {
return nil, err
}
io.Copy(&out, r)
return out.Bytes(), nil
}
func (f *Framer) initHeaderDecompression() os.Error {
if f.headerDecompressor != nil {
return nil
}
decompressor, err := zlib.NewReaderDict(f.r, []byte(HeaderDictionary))
if err != nil {
return err
}
f.headerDecompressor = decompressor
return nil
}
func (self *ZlibCompressor) DecompressFromReader(src io.Reader) ([]byte, error) {
ddest := bytes.NewBuffer(nil)
decompressor, err := zlib.NewReaderDict(src, self.dict)
if err != nil {
fmt.Println("DecompressFromReader err:%s", err.Error())
} else {
_, err = io.Copy(ddest, decompressor)
}
if err != nil {
fmt.Println("DecompressFromReader err:%s", err.Error())
}
return ddest.Bytes(), err
}
func (f *Framer) uncorkHeaderDecompressor(payloadSize int64) os.Error {
if f.headerDecompressor != nil {
f.headerReader.N = payloadSize
return nil
}
f.headerReader = io.LimitedReader{R: f.r, N: payloadSize}
decompressor, err := zlib.NewReaderDict(&f.headerReader, []byte(HeaderDictionary))
if err != nil {
return err
}
f.headerDecompressor = decompressor
return nil
}
// Decompress uses zlib decompression to decompress the provided
// data, according to the SPDY specification of the given version.
func (d *decompressor) Decompress(data []byte) (headers http.Header, err error) {
d.Lock()
defer d.Unlock()
// Make sure the buffer is ready.
if d.in == nil {
d.in = bytes.NewBuffer(data)
} else {
d.in.Reset()
d.in.Write(data)
}
// Initialise the decompressor with the appropriate
// dictionary, depending on SPDY version.
if d.out == nil {
switch d.version {
case 2:
d.out, err = zlib.NewReaderDict(d.in, HeaderDictionaryV2)
case 3:
d.out, err = zlib.NewReaderDict(d.in, HeaderDictionaryV3)
default:
err = versionError
}
if err != nil {
return nil, err
}
}
var size int
var bytesToInt func([]byte) int
// SPDY/2 uses 16-bit fixed fields, where SPDY/3 uses 32-bit fields.
switch d.version {
case 2:
size = 2
bytesToInt = func(b []byte) int {
return int(BytesToUint16(b))
}
case 3:
size = 4
bytesToInt = func(b []byte) int {
return int(BytesToUint32(b))
}
default:
return nil, versionError
}
// Read in the number of name/value pairs.
pairs, err := ReadExactly(d.out, size)
if err != nil {
return nil, err
}
numNameValuePairs := bytesToInt(pairs)
headers = make(http.Header)
bounds := MAX_FRAME_SIZE - 12 // Maximum frame size minus maximum non-headers data (SYN_STREAM)
for i := 0; i < numNameValuePairs; i++ {
var nameLength, valueLength int
// Get the name's length.
length, err := ReadExactly(d.out, size)
if err != nil {
return nil, err
}
nameLength = bytesToInt(length)
bounds -= size
if nameLength > bounds {
debug.Printf("Error: Maximum header length is %d. Received name length %d.\n", bounds, nameLength)
return nil, errors.New("Error: Incorrect header name length.")
}
bounds -= nameLength
// Get the name.
name, err := ReadExactly(d.out, nameLength)
if err != nil {
return nil, err
}
// Get the value's length.
length, err = ReadExactly(d.out, size)
if err != nil {
return nil, err
}
valueLength = bytesToInt(length)
bounds -= size
if valueLength > bounds {
debug.Printf("Error: Maximum header length is %d. Received values length %d.\n", bounds, valueLength)
return nil, errors.New("Error: Incorrect header values length.")
}
bounds -= valueLength
// Get the values.
values, err := ReadExactly(d.out, valueLength)
if err != nil {
return nil, err
}
// Split the value on null boundaries.
for _, value := range bytes.Split(values, []byte{'\x00'}) {
headers.Add(string(name), string(value))
}
}
return headers, nil
}
// NewZlibCompressionLevelDict returns a Zlib-based Compression with the given
// level, based on the given dictionary.
func NewZlibCompressionLevelDict(level int, dict []byte) Compression {
return &genericCompression{
func(w io.Writer) (io.WriteCloser, error) { return zlib.NewWriterLevelDict(w, level, dict) },
func(r io.Reader) (io.ReadCloser, error) { return zlib.NewReaderDict(r, dict) },
}
}
// Decompress uses zlib decompression to decompress the provided
// data, according to the SPDY specification of the given version.
func (d *decompressor) Decompress(data []byte) (headers http.Header, err error) {
d.m.Lock()
defer d.m.Unlock()
if d.in == nil {
d.in = bytes.NewBuffer(data)
} else {
d.in.Reset()
d.in.Write(data)
}
// Initialise the decompressor with the appropriate
// dictionary, depending on SPDY version.
if d.out == nil {
switch d.version {
case 2:
d.out, err = zlib.NewReaderDict(d.in, headerDictionaryV2)
case 3:
d.out, err = zlib.NewReaderDict(d.in, headerDictionaryV3)
default:
err = versionError
}
if err != nil {
return nil, err
}
}
var chunk []byte
var dechunk func([]byte) int
// SPDY/2 uses 16-bit fixed fields, where SPDY/3 uses 32-bit fields.
switch d.version {
case 2:
chunk = make([]byte, 2)
dechunk = func(b []byte) int {
return int(bytesToUint16(b))
}
case 3:
chunk = make([]byte, 4)
dechunk = func(b []byte) int {
return int(bytesToUint32(b))
}
default:
return nil, versionError
}
// Read in the number of name/value pairs.
if _, err = d.out.Read(chunk); err != nil {
panic(err)
return nil, err
}
numNameValuePairs := dechunk(chunk)
headers = make(http.Header)
length := 0
bounds := MAX_FRAME_SIZE - 12 // Maximum frame size minus maximum non-headers data (SYN_STREAM)
for i := 0; i < numNameValuePairs; i++ {
var nameLength, valueLength int
// Get the name.
if _, err = d.out.Read(chunk); err != nil {
return nil, err
}
nameLength = dechunk(chunk)
if nameLength > bounds {
return nil, errors.New("Error: Incorrect header name length.")
}
bounds -= nameLength
name := make([]byte, nameLength)
if _, err = d.out.Read(name); err != nil {
panic(err)
return nil, err
}
// Get the value.
if _, err = d.out.Read(chunk); err != nil {
panic(err)
return nil, err
}
valueLength = dechunk(chunk)
if valueLength > bounds {
return nil, errors.New("Error: Incorrect header values length.")
}
bounds -= valueLength
values := make([]byte, valueLength)
if _, err = d.out.Read(values); err != nil {
return nil, err
}
// Count name and ': '.
length += nameLength + 2
// Split the value on null boundaries.
for _, value := range bytes.Split(values, []byte{'\x00'}) {
headers.Add(string(name), string(value))
length += len(value) + 2 // count value and ', ' or '\n\r'.
}
}
return headers, nil
}
