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-rw-r--r--plumbing/protocol/packp/sideband/common.go33
-rw-r--r--plumbing/protocol/packp/sideband/demux.go147
-rw-r--r--plumbing/protocol/packp/sideband/demux_test.go151
-rw-r--r--plumbing/protocol/packp/sideband/doc.go31
-rw-r--r--plumbing/protocol/packp/sideband/muxer.go65
-rw-r--r--plumbing/protocol/packp/sideband/muxer_test.go39
6 files changed, 466 insertions, 0 deletions
diff --git a/plumbing/protocol/packp/sideband/common.go b/plumbing/protocol/packp/sideband/common.go
new file mode 100644
index 0000000..de50012
--- /dev/null
+++ b/plumbing/protocol/packp/sideband/common.go
@@ -0,0 +1,33 @@
+package sideband
+
+// Type sideband type "side-band" or "side-band-64k"
+type Type int8
+
+const (
+ // Sideband legacy sideband type up to 1000-byte messages
+ Sideband Type = iota
+ // Sideband64k sideband type up to 65519-byte messages
+ Sideband64k Type = iota
+
+ // MaxPackedSize for Sideband type
+ MaxPackedSize = 1000
+ // MaxPackedSize64k for Sideband64k type
+ MaxPackedSize64k = 65520
+)
+
+// Channel sideband channel
+type Channel byte
+
+// WithPayload encode the payload as a message
+func (ch Channel) WithPayload(payload []byte) []byte {
+ return append([]byte{byte(ch)}, payload...)
+}
+
+const (
+ // PackData packfile content
+ PackData Channel = 1
+ // ProgressMessage progress messages
+ ProgressMessage Channel = 2
+ // ErrorMessage fatal error message just before stream aborts
+ ErrorMessage Channel = 3
+)
diff --git a/plumbing/protocol/packp/sideband/demux.go b/plumbing/protocol/packp/sideband/demux.go
new file mode 100644
index 0000000..09fe57d
--- /dev/null
+++ b/plumbing/protocol/packp/sideband/demux.go
@@ -0,0 +1,147 @@
+package sideband
+
+import (
+ "bytes"
+ "errors"
+ "fmt"
+ "io"
+
+ "gopkg.in/src-d/go-git.v4/plumbing/format/pktline"
+)
+
+// ErrMaxPackedExceeded returned by Read, if the maximum packed size is exceeded
+var ErrMaxPackedExceeded = errors.New("max. packed size exceeded")
+
+// Progress allows to read the progress information
+type Progress interface {
+ io.Reader
+}
+
+// Demuxer demultiplex the progress reports and error info interleaved with the
+// packfile itself.
+//
+// A sideband has three diferent channels the main one call PackData contains
+// the packfile data, the ErrorMessage channel, that contains server errors and
+// the last one ProgressMessage channel containing information about the ongoing
+// tast happening in the server (optinal, can be suppressed sending NoProgress
+// or Quiet capabilities to the server)
+//
+// In order to demultiplex the data stream, method `Read` should be called to
+// retrieve the PackData channel, the incoming data from the ProgressMessage is
+// stored and can be read from `Progress` field, if any message is retrieved
+// from the ErrorMessage channel an error is returned and we can assume that the
+// conection has been closed.
+type Demuxer struct {
+ t Type
+ r io.Reader
+ s *pktline.Scanner
+
+ max int
+ pending []byte
+
+ // Progress contains progress information
+ Progress Progress
+}
+
+// NewDemuxer returns a new Demuxer for the given t and read from r
+func NewDemuxer(t Type, r io.Reader) *Demuxer {
+ max := MaxPackedSize64k
+ if t == Sideband {
+ max = MaxPackedSize
+ }
+
+ return &Demuxer{
+ t: t,
+ r: r,
+ max: max,
+ s: pktline.NewScanner(r),
+ Progress: bytes.NewBuffer(nil),
+ }
+}
+
+// Read reads up to len(p) bytes from the PackData channel into p, an error can
+// be return if an error happends when reading or if a message is sent in the
+// ErrorMessage channel.
+//
+// If a ProgressMessage is read, it won't be copied to b. Instead of this, it is
+// stored and can be read through the reader Progress. If the n value returned
+// is zero, err will be nil unless an error reading happens.
+func (d *Demuxer) Read(b []byte) (n int, err error) {
+ var read, req int
+
+ req = len(b)
+ for read < req {
+ n, err := d.doRead(b[read:req])
+ read += n
+
+ if err != nil {
+ return read, err
+ }
+ }
+
+ return read, nil
+}
+
+func (d *Demuxer) doRead(b []byte) (int, error) {
+ read, err := d.nextPackData()
+ size := len(read)
+ wanted := len(b)
+
+ if size > wanted {
+ d.pending = read[wanted:]
+ }
+
+ if wanted > size {
+ wanted = size
+ }
+
+ size = copy(b, read[:wanted])
+ return size, err
+}
+
+func (d *Demuxer) nextPackData() ([]byte, error) {
+ content := d.getPending()
+ if len(content) != 0 {
+ return content, nil
+ }
+
+ if !d.s.Scan() {
+ if err := d.s.Err(); err != nil {
+ return nil, err
+ }
+
+ return nil, io.EOF
+ }
+
+ content = d.s.Bytes()
+
+ size := len(content)
+ if size == 0 {
+ return nil, nil
+ } else if size > d.max {
+ return nil, ErrMaxPackedExceeded
+ }
+
+ switch Channel(content[0]) {
+ case PackData:
+ return content[1:], nil
+ case ProgressMessage:
+ _, err := d.Progress.(io.Writer).Write(content[1:])
+ return nil, err
+ case ErrorMessage:
+ return nil, fmt.Errorf("unexpected error: %s", content[1:])
+ default:
+ return nil, fmt.Errorf("unknown channel %s", content)
+ }
+}
+
+func (d *Demuxer) getPending() (b []byte) {
+ if len(d.pending) == 0 {
+ return nil
+ }
+
+ content := d.pending
+ d.pending = nil
+
+ return content
+}
diff --git a/plumbing/protocol/packp/sideband/demux_test.go b/plumbing/protocol/packp/sideband/demux_test.go
new file mode 100644
index 0000000..4814d89
--- /dev/null
+++ b/plumbing/protocol/packp/sideband/demux_test.go
@@ -0,0 +1,151 @@
+package sideband
+
+import (
+ "bytes"
+ "errors"
+ "io"
+ "io/ioutil"
+ "testing"
+
+ "gopkg.in/src-d/go-git.v4/plumbing/format/pktline"
+
+ . "gopkg.in/check.v1"
+)
+
+func Test(t *testing.T) { TestingT(t) }
+
+type SidebandSuite struct{}
+
+var _ = Suite(&SidebandSuite{})
+
+func (s *SidebandSuite) TestDecode(c *C) {
+ expected := []byte("abcdefghijklmnopqrstuvwxyz")
+
+ buf := bytes.NewBuffer(nil)
+ e := pktline.NewEncoder(buf)
+ e.Encode(PackData.WithPayload(expected[0:8]))
+ e.Encode(PackData.WithPayload(expected[8:16]))
+ e.Encode(PackData.WithPayload(expected[16:26]))
+
+ content := make([]byte, 26)
+ d := NewDemuxer(Sideband64k, buf)
+ n, err := io.ReadFull(d, content)
+ c.Assert(err, IsNil)
+ c.Assert(n, Equals, 26)
+ c.Assert(content, DeepEquals, expected)
+}
+
+func (s *SidebandSuite) TestDecodeMoreThanContain(c *C) {
+ expected := []byte("abcdefghijklmnopqrstuvwxyz")
+
+ buf := bytes.NewBuffer(nil)
+ e := pktline.NewEncoder(buf)
+ e.Encode(PackData.WithPayload(expected))
+
+ content := make([]byte, 42)
+ d := NewDemuxer(Sideband64k, buf)
+ n, err := io.ReadFull(d, content)
+ c.Assert(err, Equals, io.ErrUnexpectedEOF)
+ c.Assert(n, Equals, 26)
+ c.Assert(content[0:26], DeepEquals, expected)
+}
+
+func (s *SidebandSuite) TestDecodeWithError(c *C) {
+ expected := []byte("abcdefghijklmnopqrstuvwxyz")
+
+ buf := bytes.NewBuffer(nil)
+ e := pktline.NewEncoder(buf)
+ e.Encode(PackData.WithPayload(expected[0:8]))
+ e.Encode(ErrorMessage.WithPayload([]byte{'F', 'O', 'O', '\n'}))
+ e.Encode(PackData.WithPayload(expected[8:16]))
+ e.Encode(PackData.WithPayload(expected[16:26]))
+
+ content := make([]byte, 26)
+ d := NewDemuxer(Sideband64k, buf)
+ n, err := io.ReadFull(d, content)
+ c.Assert(err, ErrorMatches, "unexpected error: FOO\n")
+ c.Assert(n, Equals, 8)
+ c.Assert(content[0:8], DeepEquals, expected[0:8])
+}
+
+type mockReader struct{}
+
+func (r *mockReader) Read([]byte) (int, error) { return 0, errors.New("foo") }
+
+func (s *SidebandSuite) TestDecodeFromFailingReader(c *C) {
+ content := make([]byte, 26)
+ d := NewDemuxer(Sideband64k, &mockReader{})
+ n, err := io.ReadFull(d, content)
+ c.Assert(err, ErrorMatches, "foo")
+ c.Assert(n, Equals, 0)
+}
+
+func (s *SidebandSuite) TestDecodeWithProgress(c *C) {
+ expected := []byte("abcdefghijklmnopqrstuvwxyz")
+
+ buf := bytes.NewBuffer(nil)
+ e := pktline.NewEncoder(buf)
+ e.Encode(PackData.WithPayload(expected[0:8]))
+ e.Encode(ProgressMessage.WithPayload([]byte{'F', 'O', 'O', '\n'}))
+ e.Encode(PackData.WithPayload(expected[8:16]))
+ e.Encode(PackData.WithPayload(expected[16:26]))
+
+ content := make([]byte, 26)
+ d := NewDemuxer(Sideband64k, buf)
+ n, err := io.ReadFull(d, content)
+ c.Assert(err, IsNil)
+ c.Assert(n, Equals, 26)
+ c.Assert(content, DeepEquals, expected)
+
+ progress, err := ioutil.ReadAll(d.Progress)
+ c.Assert(err, IsNil)
+ c.Assert(progress, DeepEquals, []byte{'F', 'O', 'O', '\n'})
+}
+
+func (s *SidebandSuite) TestDecodeWithUnknownChannel(c *C) {
+
+ buf := bytes.NewBuffer(nil)
+ e := pktline.NewEncoder(buf)
+ e.Encode([]byte{'4', 'F', 'O', 'O', '\n'})
+
+ content := make([]byte, 26)
+ d := NewDemuxer(Sideband64k, buf)
+ n, err := io.ReadFull(d, content)
+ c.Assert(err, ErrorMatches, "unknown channel 4FOO\n")
+ c.Assert(n, Equals, 0)
+}
+
+func (s *SidebandSuite) TestDecodeWithPending(c *C) {
+ expected := []byte("abcdefghijklmnopqrstuvwxyz")
+
+ buf := bytes.NewBuffer(nil)
+ e := pktline.NewEncoder(buf)
+ e.Encode(PackData.WithPayload(expected[0:8]))
+ e.Encode(PackData.WithPayload(expected[8:16]))
+ e.Encode(PackData.WithPayload(expected[16:26]))
+
+ content := make([]byte, 13)
+ d := NewDemuxer(Sideband64k, buf)
+ n, err := io.ReadFull(d, content)
+ c.Assert(err, IsNil)
+ c.Assert(n, Equals, 13)
+ c.Assert(content, DeepEquals, expected[0:13])
+
+ n, err = d.Read(content)
+ c.Assert(err, IsNil)
+ c.Assert(n, Equals, 13)
+ c.Assert(content, DeepEquals, expected[13:26])
+}
+
+func (s *SidebandSuite) TestDecodeErrMaxPacked(c *C) {
+ buf := bytes.NewBuffer(nil)
+ e := pktline.NewEncoder(buf)
+ e.Encode(PackData.WithPayload(bytes.Repeat([]byte{'0'}, MaxPackedSize+1)))
+
+ content := make([]byte, 13)
+ d := NewDemuxer(Sideband, buf)
+ n, err := io.ReadFull(d, content)
+ c.Assert(err, Equals, ErrMaxPackedExceeded)
+ c.Assert(n, Equals, 0)
+
+}
diff --git a/plumbing/protocol/packp/sideband/doc.go b/plumbing/protocol/packp/sideband/doc.go
new file mode 100644
index 0000000..c5d2429
--- /dev/null
+++ b/plumbing/protocol/packp/sideband/doc.go
@@ -0,0 +1,31 @@
+// Package sideband implements a sideband mutiplex/demultiplexer
+package sideband
+
+// If 'side-band' or 'side-band-64k' capabilities have been specified by
+// the client, the server will send the packfile data multiplexed.
+//
+// Either mode indicates that the packfile data will be streamed broken
+// up into packets of up to either 1000 bytes in the case of 'side_band',
+// or 65520 bytes in the case of 'side_band_64k'. Each packet is made up
+// of a leading 4-byte pkt-line length of how much data is in the packet,
+// followed by a 1-byte stream code, followed by the actual data.
+//
+// The stream code can be one of:
+//
+// 1 - pack data
+// 2 - progress messages
+// 3 - fatal error message just before stream aborts
+//
+// The "side-band-64k" capability came about as a way for newer clients
+// that can handle much larger packets to request packets that are
+// actually crammed nearly full, while maintaining backward compatibility
+// for the older clients.
+//
+// Further, with side-band and its up to 1000-byte messages, it's actually
+// 999 bytes of payload and 1 byte for the stream code. With side-band-64k,
+// same deal, you have up to 65519 bytes of data and 1 byte for the stream
+// code.
+//
+// The client MUST send only maximum of one of "side-band" and "side-
+// band-64k". Server MUST diagnose it as an error if client requests
+// both.
diff --git a/plumbing/protocol/packp/sideband/muxer.go b/plumbing/protocol/packp/sideband/muxer.go
new file mode 100644
index 0000000..2ab7da8
--- /dev/null
+++ b/plumbing/protocol/packp/sideband/muxer.go
@@ -0,0 +1,65 @@
+package sideband
+
+import (
+ "io"
+
+ "gopkg.in/src-d/go-git.v4/plumbing/format/pktline"
+)
+
+// Muxer multiplex the packfile along with the progress messages and the error
+// information. The multiplex is perform using pktline format.
+type Muxer struct {
+ max int
+ e *pktline.Encoder
+}
+
+const chLen = 1
+
+// NewMuxer returns a new Muxer for the given t that writes on w.
+//
+// If t is equal to `Sideband` the max pack size is set to MaxPackedSize, in any
+// other value is given, max pack is set to MaxPackedSize64k, that is the
+// maximum lenght of a line in pktline format.
+func NewMuxer(t Type, w io.Writer) *Muxer {
+ max := MaxPackedSize64k
+ if t == Sideband {
+ max = MaxPackedSize
+ }
+
+ return &Muxer{
+ max: max - chLen,
+ e: pktline.NewEncoder(w),
+ }
+}
+
+// Write writes p in the PackData channel
+func (m *Muxer) Write(p []byte) (int, error) {
+ return m.WriteChannel(PackData, p)
+}
+
+// WriteChannel writes p in the given channel. This method can be used with any
+// channel, but is recommend use it only for the ProgressMessage and
+// ErrorMessage channels and use Write for the PackData channel
+func (m *Muxer) WriteChannel(t Channel, p []byte) (int, error) {
+ wrote := 0
+ size := len(p)
+ for wrote < size {
+ n, err := m.doWrite(t, p[wrote:])
+ wrote += n
+
+ if err != nil {
+ return wrote, err
+ }
+ }
+
+ return wrote, nil
+}
+
+func (m *Muxer) doWrite(ch Channel, p []byte) (int, error) {
+ sz := len(p)
+ if sz > m.max {
+ sz = m.max
+ }
+
+ return sz, m.e.Encode(ch.WithPayload(p[:sz]))
+}
diff --git a/plumbing/protocol/packp/sideband/muxer_test.go b/plumbing/protocol/packp/sideband/muxer_test.go
new file mode 100644
index 0000000..38fc4bd
--- /dev/null
+++ b/plumbing/protocol/packp/sideband/muxer_test.go
@@ -0,0 +1,39 @@
+package sideband
+
+import (
+ "bytes"
+
+ . "gopkg.in/check.v1"
+)
+
+func (s *SidebandSuite) TestMuxerWrite(c *C) {
+ buf := bytes.NewBuffer(nil)
+
+ m := NewMuxer(Sideband, buf)
+
+ n, err := m.Write(bytes.Repeat([]byte{'F'}, (MaxPackedSize-1)*2))
+ c.Assert(err, IsNil)
+ c.Assert(n, Equals, 1998)
+ c.Assert(buf.Len(), Equals, 2008)
+}
+
+func (s *SidebandSuite) TestMuxerWriteChannelMultipleChannels(c *C) {
+ buf := bytes.NewBuffer(nil)
+
+ m := NewMuxer(Sideband, buf)
+
+ n, err := m.WriteChannel(PackData, bytes.Repeat([]byte{'D'}, 4))
+ c.Assert(err, IsNil)
+ c.Assert(n, Equals, 4)
+
+ n, err = m.WriteChannel(ProgressMessage, bytes.Repeat([]byte{'P'}, 4))
+ c.Assert(err, IsNil)
+ c.Assert(n, Equals, 4)
+
+ n, err = m.WriteChannel(PackData, bytes.Repeat([]byte{'D'}, 4))
+ c.Assert(err, IsNil)
+ c.Assert(n, Equals, 4)
+
+ c.Assert(buf.Len(), Equals, 27)
+ c.Assert(buf.String(), Equals, "0009\x01DDDD0009\x02PPPP0009\x01DDDD")
+}