From 68cfde6207a3d47c1154fe5c51a23decd8978c27 Mon Sep 17 00:00:00 2001 From: Jordan Orelli Date: Sun, 31 Jul 2016 18:38:14 -0400 Subject: [PATCH] check compressed flag on commands --- parser.go | 34 ++++++++++++++++++++++------------ 1 file changed, 22 insertions(+), 12 deletions(-) diff --git a/parser.go b/parser.go index 3c9c3a8..c4c5519 100644 --- a/parser.go +++ b/parser.go @@ -53,7 +53,10 @@ func (p *parser) run() { // This is the format for the // int32, int64, uint32, uint64, bool, and enum func (p *parser) decodeVarint() (uint64, error) { - buf, err := p.source.Peek(9) + // protobuf defines values that are up to 64 bits wide. The largest value + // stored in a protobuf varint is 64 data bits, which in varint encoding, + // would require 10 bytes. + buf, err := p.source.Peek(10) if err != nil { return 0, fmt.Errorf("decode varint couldn't peek 9 bytes: %v", err) } @@ -101,29 +104,36 @@ func (p *parser) checkHeader() (bool, error) { return string(buf) == replayHeader, nil } -func (p *parser) readCommand() (EDemoCommands, error) { +func (p *parser) readCommand() (EDemoCommands, bool, error) { n, err := p.decodeVarint() if err != nil { - return EDemoCommands_DEM_Error, fmt.Errorf("readCommand couldn't read varint: %v", err) + return EDemoCommands_DEM_Error, false, fmt.Errorf("readCommand couldn't read varint: %v", err) } - return EDemoCommands(n), nil + + compressed := false + if n&0x40 > 0 { + compressed = true + n &^= 0x40 + } + return EDemoCommands(n), compressed, nil } type message struct { - cmd EDemoCommands - tick int64 - body []byte + cmd EDemoCommands + tick int64 + compressed bool + body []byte } func (m *message) String() string { if len(m.body) > 30 { - return fmt.Sprintf("{cmd: %v tick: %v body: %q...}", m.cmd, m.tick, m.body[:27]) + return fmt.Sprintf("{cmd: %v tick: %v compressed: %t body(%d): %q...}", m.cmd, m.tick, m.compressed, len(m.body), m.body[:27]) } - return fmt.Sprintf("{cmd: %v tick: %v body: %q}", m.cmd, m.tick, m.body) + return fmt.Sprintf("{cmd: %v tick: %v compressed: %t body(%d): %q}", m.cmd, m.tick, m.compressed, len(m.body), m.body) } func (p *parser) readMessage() (*message, error) { - cmd, err := p.readCommand() + cmd, compressed, err := p.readCommand() if err != nil { return nil, fmt.Errorf("readMessage couldn't get a command: %v", err) } @@ -143,8 +153,8 @@ func (p *parser) readMessage() (*message, error) { if err != nil { return nil, fmt.Errorf("readMessage couldn't read message body: %v", err) } - return &message{cmd, int64(tick), buf}, nil + return &message{cmd, int64(tick), compressed, buf}, nil } - return &message{cmd, int64(tick), nil}, nil + return &message{cmd, int64(tick), compressed, nil}, nil }