diff options
Diffstat (limited to 'src/pkg/http/spdy/read.go')
-rw-r--r-- | src/pkg/http/spdy/read.go | 287 |
1 files changed, 287 insertions, 0 deletions
diff --git a/src/pkg/http/spdy/read.go b/src/pkg/http/spdy/read.go new file mode 100644 index 000000000..159dbc578 --- /dev/null +++ b/src/pkg/http/spdy/read.go @@ -0,0 +1,287 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package spdy + +import ( + "compress/zlib" + "encoding/binary" + "http" + "io" + "os" + "strings" +) + +func (frame *SynStreamFrame) read(h ControlFrameHeader, f *Framer) os.Error { + return f.readSynStreamFrame(h, frame) +} + +func (frame *SynReplyFrame) read(h ControlFrameHeader, f *Framer) os.Error { + return f.readSynReplyFrame(h, frame) +} + +func (frame *RstStreamFrame) read(h ControlFrameHeader, f *Framer) os.Error { + frame.CFHeader = h + if err := binary.Read(f.r, binary.BigEndian, &frame.StreamId); err != nil { + return err + } + if err := binary.Read(f.r, binary.BigEndian, &frame.Status); err != nil { + return err + } + return nil +} + +func (frame *SettingsFrame) read(h ControlFrameHeader, f *Framer) os.Error { + frame.CFHeader = h + var numSettings uint32 + if err := binary.Read(f.r, binary.BigEndian, &numSettings); err != nil { + return err + } + frame.FlagIdValues = make([]SettingsFlagIdValue, numSettings) + for i := uint32(0); i < numSettings; i++ { + if err := binary.Read(f.r, binary.BigEndian, &frame.FlagIdValues[i].Id); err != nil { + return err + } + frame.FlagIdValues[i].Flag = SettingsFlag((frame.FlagIdValues[i].Id & 0xff000000) >> 24) + frame.FlagIdValues[i].Id &= 0xffffff + if err := binary.Read(f.r, binary.BigEndian, &frame.FlagIdValues[i].Value); err != nil { + return err + } + } + return nil +} + +func (frame *NoopFrame) read(h ControlFrameHeader, f *Framer) os.Error { + frame.CFHeader = h + return nil +} + +func (frame *PingFrame) read(h ControlFrameHeader, f *Framer) os.Error { + frame.CFHeader = h + if err := binary.Read(f.r, binary.BigEndian, &frame.Id); err != nil { + return err + } + return nil +} + +func (frame *GoAwayFrame) read(h ControlFrameHeader, f *Framer) os.Error { + frame.CFHeader = h + if err := binary.Read(f.r, binary.BigEndian, &frame.LastGoodStreamId); err != nil { + return err + } + return nil +} + +func (frame *HeadersFrame) read(h ControlFrameHeader, f *Framer) os.Error { + return f.readHeadersFrame(h, frame) +} + +func newControlFrame(frameType ControlFrameType) (controlFrame, os.Error) { + ctor, ok := cframeCtor[frameType] + if !ok { + return nil, InvalidControlFrame + } + return ctor(), nil +} + +var cframeCtor = map[ControlFrameType]func() controlFrame{ + TypeSynStream: func() controlFrame { return new(SynStreamFrame) }, + TypeSynReply: func() controlFrame { return new(SynReplyFrame) }, + TypeRstStream: func() controlFrame { return new(RstStreamFrame) }, + TypeSettings: func() controlFrame { return new(SettingsFrame) }, + TypeNoop: func() controlFrame { return new(NoopFrame) }, + TypePing: func() controlFrame { return new(PingFrame) }, + TypeGoAway: func() controlFrame { return new(GoAwayFrame) }, + TypeHeaders: func() controlFrame { return new(HeadersFrame) }, + // TODO(willchan): Add TypeWindowUpdate +} + +type corkedReader struct { + r io.Reader + ch chan int + n int +} + +func (cr *corkedReader) Read(p []byte) (int, os.Error) { + if cr.n == 0 { + cr.n = <-cr.ch + } + if len(p) > cr.n { + p = p[:cr.n] + } + n, err := cr.r.Read(p) + cr.n -= n + return n, err +} + +func (f *Framer) uncorkHeaderDecompressor(payloadSize int) os.Error { + if f.headerDecompressor != nil { + f.headerReader.ch <- payloadSize + return nil + } + f.headerReader = corkedReader{r: f.r, ch: make(chan int, 1), n: payloadSize} + decompressor, err := zlib.NewReaderDict(&f.headerReader, []byte(HeaderDictionary)) + if err != nil { + return err + } + f.headerDecompressor = decompressor + return nil +} + +// ReadFrame reads SPDY encoded data and returns a decompressed Frame. +func (f *Framer) ReadFrame() (Frame, os.Error) { + var firstWord uint32 + if err := binary.Read(f.r, binary.BigEndian, &firstWord); err != nil { + return nil, err + } + if (firstWord & 0x80000000) != 0 { + frameType := ControlFrameType(firstWord & 0xffff) + version := uint16(0x7fff & (firstWord >> 16)) + return f.parseControlFrame(version, frameType) + } + return f.parseDataFrame(firstWord & 0x7fffffff) +} + +func (f *Framer) parseControlFrame(version uint16, frameType ControlFrameType) (Frame, os.Error) { + var length uint32 + if err := binary.Read(f.r, binary.BigEndian, &length); err != nil { + return nil, err + } + flags := ControlFlags((length & 0xff000000) >> 24) + length &= 0xffffff + header := ControlFrameHeader{version, frameType, flags, length} + cframe, err := newControlFrame(frameType) + if err != nil { + return nil, err + } + if err = cframe.read(header, f); err != nil { + return nil, err + } + return cframe, nil +} + +func parseHeaderValueBlock(r io.Reader) (http.Header, os.Error) { + var numHeaders uint16 + if err := binary.Read(r, binary.BigEndian, &numHeaders); err != nil { + return nil, err + } + h := make(http.Header, int(numHeaders)) + for i := 0; i < int(numHeaders); i++ { + var length uint16 + if err := binary.Read(r, binary.BigEndian, &length); err != nil { + return nil, err + } + nameBytes := make([]byte, length) + if _, err := io.ReadFull(r, nameBytes); err != nil { + return nil, err + } + name := string(nameBytes) + if name != strings.ToLower(name) { + return nil, UnlowercasedHeaderName + } + if h[name] != nil { + return nil, DuplicateHeaders + } + if err := binary.Read(r, binary.BigEndian, &length); err != nil { + return nil, err + } + value := make([]byte, length) + if _, err := io.ReadFull(r, value); err != nil { + return nil, err + } + valueList := strings.Split(string(value), "\x00", -1) + for _, v := range valueList { + h.Add(name, v) + } + } + return h, nil +} + +func (f *Framer) readSynStreamFrame(h ControlFrameHeader, frame *SynStreamFrame) os.Error { + frame.CFHeader = h + var err os.Error + if err = binary.Read(f.r, binary.BigEndian, &frame.StreamId); err != nil { + return err + } + if err = binary.Read(f.r, binary.BigEndian, &frame.AssociatedToStreamId); err != nil { + return err + } + if err = binary.Read(f.r, binary.BigEndian, &frame.Priority); err != nil { + return err + } + frame.Priority >>= 14 + + reader := f.r + if !f.headerCompressionDisabled { + f.uncorkHeaderDecompressor(int(h.length - 10)) + reader = f.headerDecompressor + } + + frame.Headers, err = parseHeaderValueBlock(reader) + if err != nil { + return err + } + return nil +} + +func (f *Framer) readSynReplyFrame(h ControlFrameHeader, frame *SynReplyFrame) os.Error { + frame.CFHeader = h + var err os.Error + if err = binary.Read(f.r, binary.BigEndian, &frame.StreamId); err != nil { + return err + } + var unused uint16 + if err = binary.Read(f.r, binary.BigEndian, &unused); err != nil { + return err + } + reader := f.r + if !f.headerCompressionDisabled { + f.uncorkHeaderDecompressor(int(h.length - 6)) + reader = f.headerDecompressor + } + frame.Headers, err = parseHeaderValueBlock(reader) + if err != nil { + return err + } + return nil +} + +func (f *Framer) readHeadersFrame(h ControlFrameHeader, frame *HeadersFrame) os.Error { + frame.CFHeader = h + var err os.Error + if err = binary.Read(f.r, binary.BigEndian, &frame.StreamId); err != nil { + return err + } + var unused uint16 + if err = binary.Read(f.r, binary.BigEndian, &unused); err != nil { + return err + } + reader := f.r + if !f.headerCompressionDisabled { + f.uncorkHeaderDecompressor(int(h.length - 6)) + reader = f.headerDecompressor + } + frame.Headers, err = parseHeaderValueBlock(reader) + if err != nil { + return err + } + return nil +} + +func (f *Framer) parseDataFrame(streamId uint32) (*DataFrame, os.Error) { + var length uint32 + if err := binary.Read(f.r, binary.BigEndian, &length); err != nil { + return nil, err + } + var frame DataFrame + frame.StreamId = streamId + frame.Flags = DataFlags(length >> 24) + length &= 0xffffff + frame.Data = make([]byte, length) + // TODO(willchan): Support compressed data frames. + if _, err := io.ReadFull(f.r, frame.Data); err != nil { + return nil, err + } + return &frame, nil +} |