ref: af08c84539f9353718604988ba27ae3c466860fc
parent: 27ef9a7e1f2589d1a0eeee4cd6d36d1926989cf2
author: Runxi Yu <me@runxiyu.org>
date: Tue Mar 10 09:28:59 EDT 2026
*: Move sideband64k and pktline to protocol/
--- a/cmd/receivepack9418/errpkt.go
+++ b/cmd/receivepack9418/errpkt.go
@@ -3,7 +3,7 @@
import (
"io"
- "codeberg.org/lindenii/furgit/format/pktline"
+ "codeberg.org/lindenii/furgit/protocol/pktline"
)
func writeErrPkt(w io.Writer, message string) {--- a/cmd/receivepack9418/gitproto.go
+++ b/cmd/receivepack9418/gitproto.go
@@ -4,7 +4,7 @@
"fmt"
"io"
- "codeberg.org/lindenii/furgit/format/pktline"
+ "codeberg.org/lindenii/furgit/protocol/pktline"
)
func readGitProtoRequest(r io.Reader) (gitProtoRequest, error) {--- a/format/pktline/append.go
+++ /dev/null
@@ -1,39 +1,0 @@
-package pktline
-
-import "fmt"
-
-// AppendData appends one data frame to dst.
-//
-// Empty payload is encoded as 0004.
-func AppendData(dst, payload []byte) ([]byte, error) {- if len(payload) > LargePacketDataMax {- return dst, fmt.Errorf("%w: %d > %d", ErrTooLarge, len(payload), LargePacketDataMax)- }
-
- var hdr [4]byte
-
- err := EncodeLengthHeader(&hdr, len(payload)+4)
- if err != nil {- return dst, err
- }
-
- dst = append(dst, hdr[:]...)
- dst = append(dst, payload...)
-
- return dst, nil
-}
-
-// AppendFlushPkt appends control frame 0000 (flush-pkt).
-func AppendFlushPkt(dst []byte) []byte {- return append(dst, '0', '0', '0', '0')
-}
-
-// AppendDelimPkt appends control frame 0001 (delim-pkt).
-func AppendDelimPkt(dst []byte) []byte {- return append(dst, '0', '0', '0', '1')
-}
-
-// AppendResponseEndPkt appends control frame 0002 (response-end-pkt).
-func AppendResponseEndPkt(dst []byte) []byte {- return append(dst, '0', '0', '0', '2')
-}
--- a/format/pktline/append_data_preserves_dst_on_error_test.go
+++ /dev/null
@@ -1,25 +1,0 @@
-package pktline_test
-
-import (
- "bytes"
- "errors"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/pktline"
-)
-
-func TestAppendDataPreservesDstOnError(t *testing.T) {- t.Parallel()
-
- orig := []byte("seed")- dst := append([]byte(nil), orig...)
-
- out, err := pktline.AppendData(dst, bytes.Repeat([]byte{'x'}, pktline.LargePacketDataMax+1))- if !errors.Is(err, pktline.ErrTooLarge) {- t.Fatalf("got err %v, want ErrTooLarge", err)- }
-
- if !bytes.Equal(out, orig) {- t.Fatalf("got %q, want %q", string(out), string(orig))- }
-}
--- a/format/pktline/append_helpers_test.go
+++ /dev/null
@@ -1,24 +1,0 @@
-package pktline_test
-
-import (
- "testing"
-
- "codeberg.org/lindenii/furgit/format/pktline"
-)
-
-func TestAppendHelpers(t *testing.T) {- t.Parallel()
-
- out, err := pktline.AppendData(nil, []byte("ok"))- if err != nil {- t.Fatalf("AppendData: %v", err)- }
-
- out = pktline.AppendFlushPkt(out)
- out = pktline.AppendDelimPkt(out)
- out = pktline.AppendResponseEndPkt(out)
-
- if got, want := string(out), "0006ok000000010002"; got != want {- t.Fatalf("got %q, want %q", got, want)- }
-}
--- a/format/pktline/chunk_writer.go
+++ /dev/null
@@ -1,65 +1,0 @@
-package pktline
-
-import "io"
-
-// ChunkWriter packetizes arbitrary stream bytes into data pkt-lines.
-// It never writes control packets automatically.
-type ChunkWriter struct {- enc *Encoder
-}
-
-// NewChunkWriter creates a chunking adapter over enc.
-func NewChunkWriter(enc *Encoder) *ChunkWriter {- return &ChunkWriter{enc: enc}-}
-
-// Write splits p into data frames not larger than enc's maxData.
-//
-// It implements io.Writer.
-func (cw *ChunkWriter) Write(p []byte) (int, error) {- total := 0
- maxData := cw.enc.effectiveMaxData()
-
- for len(p) > 0 {- n := min(len(p), maxData)
-
- err := cw.enc.WriteData(p[:n])
- if err != nil {- return total, err
- }
-
- total += n
- p = p[n:]
- }
-
- return total, nil
-}
-
-// ReadFrom reads from r and writes pkt-line data frames to the encoder.
-//
-// It implements io.ReaderFrom.
-func (cw *ChunkWriter) ReadFrom(r io.Reader) (int64, error) {- buf := make([]byte, cw.enc.effectiveMaxData())
-
- var total int64
-
- for {- n, err := r.Read(buf)
- if n > 0 {- werr := cw.enc.WriteData(buf[:n])
- if werr != nil {- return total, werr
- }
-
- total += int64(n)
- }
-
- if err != nil {- if err == io.EOF {- return total, nil
- }
-
- return total, err
- }
- }
-}
--- a/format/pktline/chunk_writer_write_and_read_from_test.go
+++ /dev/null
@@ -1,60 +1,0 @@
-package pktline_test
-
-import (
- "bufio"
- "bytes"
- "strings"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/pktline"
-)
-
-func TestChunkWriterWriteAndReadFrom(t *testing.T) {- t.Parallel()
-
- var out bytes.Buffer
-
- bw := bufio.NewWriter(&out)
-
- enc := pktline.NewEncoder(bw)
- enc.SetMaxData(3)
- cw := pktline.NewChunkWriter(enc)
-
- n, err := cw.Write([]byte("abcdefg"))- if err != nil {- t.Fatalf("Write: %v", err)- }
-
- if n != 7 {- t.Fatalf("Write n=%d, want 7", n)- }
-
- err = enc.FlushIO()
- if err != nil {- t.Fatalf("FlushIO: %v", err)- }
-
- if got, want := out.String(), "0007abc0007def0005g"; got != want {- t.Fatalf("got %q, want %q", got, want)- }
-
- out.Reset()
-
- rn, err := cw.ReadFrom(strings.NewReader("wxyz"))- if err != nil {- t.Fatalf("ReadFrom: %v", err)- }
-
- if rn != 4 {- t.Fatalf("ReadFrom n=%d, want 4", rn)- }
-
- err = enc.FlushIO()
- if err != nil {- t.Fatalf("FlushIO: %v", err)- }
-
- if got, want := out.String(), "0007wxy0005z"; got != want {- t.Fatalf("got %q, want %q", got, want)- }
-}
--- a/format/pktline/constants.go
+++ /dev/null
@@ -1,12 +1,0 @@
-package pktline
-
-const (
- // DefaultPacketMax is a conservative packet size commonly used by
- // line-oriented protocol messages.
- DefaultPacketMax = 1000
- // LargePacketMax is the maximum on-wire packet size including the
- // 4-byte hexadecimal length header.
- LargePacketMax = 65520
- // LargePacketDataMax is the maximum payload size in one packet.
- LargePacketDataMax = LargePacketMax - 4
-)
--- a/format/pktline/decoder.go
+++ /dev/null
@@ -1,187 +1,0 @@
-package pktline
-
-import (
- "errors"
- "fmt"
- "io"
-)
-
-// ReadOptions controls decoding behavior.
-type ReadOptions struct {- // ChompLF removes one trailing '\n' from PacketData payloads.
- ChompLF bool
-}
-
-// Decoder reads pkt-line frames from an io.Reader.
-//
-// It is advisable to supply a buffered reader.
-//
-// It preserves frame boundaries and supports one-frame lookahead via PeekFrame.
-type Decoder struct {- r io.Reader
- maxData int
- opts ReadOptions
-
- peeked bool
- peek Frame
- peekErr error
-}
-
-// NewDecoder creates a decoder over r.
-func NewDecoder(r io.Reader, opts ReadOptions) *Decoder {- return &Decoder{- r: r,
- maxData: LargePacketDataMax,
- opts: opts,
- }
-}
-
-// SetMaxData sets maximum payload size accepted for one data packet.
-//
-// Non-positive n resets to LargePacketDataMax.
-func (d *Decoder) SetMaxData(n int) {- if n <= 0 {- d.maxData = LargePacketDataMax
-
- return
- }
-
- d.maxData = n
-}
-
-func cloneFrame(f Frame) Frame {- if f.Type != PacketData {- return Frame{Type: f.Type}- }
-
- out := Frame{Type: f.Type}- if f.Payload != nil {- out.Payload = append([]byte(nil), f.Payload...)
- }
-
- return out
-}
-
-// ReadFrame reads one frame.
-//
-// 0000 is a PacketFlush
-// 0001 is a PacketDelim
-// 0002 is a PacketResponseEnd
-// 0004 is a PacketData with empty payload
-//
-// 0003 and malformed headers return *ProtocolError.
-func (d *Decoder) ReadFrame() (Frame, error) {- if d.peeked {- d.peeked = false
-
- return cloneFrame(d.peek), d.peekErr
- }
-
- return d.readFrame()
-}
-
-// PeekFrame returns the next frame without consuming it.
-//
-// A subsequent ReadFrame returns the same frame.
-func (d *Decoder) PeekFrame() (Frame, error) {- if !d.peeked {- d.peek, d.peekErr = d.readFrame()
- d.peeked = true
- }
-
- return cloneFrame(d.peek), d.peekErr
-}
-
-func (d *Decoder) readFrame() (Frame, error) {- var hdr [4]byte
-
- _, err := io.ReadFull(d.r, hdr[:])
- if err != nil {- if errors.Is(err, io.EOF) {- return Frame{}, io.EOF- }
-
- if errors.Is(err, io.ErrUnexpectedEOF) {- return Frame{}, io.ErrUnexpectedEOF- }
-
- return Frame{}, err- }
-
- n, err := ParseLengthHeader(hdr)
- if err != nil {- return Frame{}, &ProtocolError{Header: hdr, Reason: err.Error()}- }
-
- switch n {- case 0:
- return Frame{Type: PacketFlush}, nil- case 1:
- return Frame{Type: PacketDelim}, nil- case 2:
- return Frame{Type: PacketResponseEnd}, nil- case 3:
- return Frame{}, &ProtocolError{Header: hdr, Reason: "invalid pkt-line length 3"}- }
-
- if n < 4 {- return Frame{}, &ProtocolError{Header: hdr, Reason: fmt.Sprintf("invalid pkt-line length %d", n)}- }
-
- if n > LargePacketMax {- perr := &ProtocolError{Header: hdr, Reason: fmt.Sprintf("pkt-line length %d exceeds max %d", n, LargePacketMax)}-
- err := d.discardPayload(n - 4)
- if err != nil {- return Frame{}, errors.Join(perr, err)- }
-
- return Frame{}, perr- }
-
- payloadLen := n - 4
- if payloadLen > d.maxData {- serr := fmt.Errorf("%w: %d > %d", ErrTooLarge, payloadLen, d.maxData)-
- err := d.discardPayload(payloadLen)
- if err != nil {- return Frame{}, errors.Join(serr, err)- }
-
- return Frame{}, serr- }
-
- payload := make([]byte, payloadLen)
-
- _, err = io.ReadFull(d.r, payload)
- if err != nil {- if errors.Is(err, io.EOF) || errors.Is(err, io.ErrUnexpectedEOF) {- return Frame{}, io.ErrUnexpectedEOF- }
-
- return Frame{}, err- }
-
- if d.opts.ChompLF && len(payload) > 0 && payload[len(payload)-1] == '\n' {- payload = payload[:len(payload)-1]
- }
-
- return Frame{Type: PacketData, Payload: payload}, nil-}
-
-func (d *Decoder) discardPayload(n int) error {- if n <= 0 {- return nil
- }
-
- _, err := io.CopyN(io.Discard, d.r, int64(n))
- if err == nil {- return nil
- }
-
- if errors.Is(err, io.EOF) || errors.Is(err, io.ErrUnexpectedEOF) {- return io.ErrUnexpectedEOF
- }
-
- return err
-}
--- a/format/pktline/decoder_data_control_and_0004_test.go
+++ /dev/null
@@ -1,60 +1,0 @@
-package pktline_test
-
-import (
- "strings"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/pktline"
-)
-
-func TestDecoderDataControlAnd0004(t *testing.T) {- t.Parallel()
-
- input := "0006a\n0004000100020000"
- dec := pktline.NewDecoder(strings.NewReader(input), pktline.ReadOptions{ChompLF: true})-
- f, err := dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame #1: %v", err)- }
-
- if f.Type != pktline.PacketData || string(f.Payload) != "a" {- t.Fatalf("frame #1 = %#v", f)- }
-
- f, err = dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame #2: %v", err)- }
-
- if f.Type != pktline.PacketData || len(f.Payload) != 0 {- t.Fatalf("frame #2 = %#v, want empty data", f)- }
-
- f, err = dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame #3: %v", err)- }
-
- if f.Type != pktline.PacketDelim {- t.Fatalf("frame #3 type = %v, want PacketDelim", f.Type)- }
-
- f, err = dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame #4: %v", err)- }
-
- if f.Type != pktline.PacketResponseEnd {- t.Fatalf("frame #4 type = %v, want PacketResponseEnd", f.Type)- }
-
- f, err = dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame #5: %v", err)- }
-
- if f.Type != pktline.PacketFlush {- t.Fatalf("frame #5 type = %v, want PacketFlush", f.Type)- }
-}
--- a/format/pktline/decoder_invalid_0003_test.go
+++ /dev/null
@@ -1,20 +1,0 @@
-package pktline_test
-
-import (
- "errors"
- "strings"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/pktline"
-)
-
-func TestDecoderInvalid0003(t *testing.T) {- t.Parallel()
-
- dec := pktline.NewDecoder(strings.NewReader("0003"), pktline.ReadOptions{})- _, err := dec.ReadFrame()
-
- if _, ok := errors.AsType[*pktline.ProtocolError](err); !ok {- t.Fatalf("got err %v, want ProtocolError", err)- }
-}
--- a/format/pktline/decoder_peek_test.go
+++ /dev/null
@@ -1,32 +1,0 @@
-package pktline_test
-
-import (
- "strings"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/pktline"
-)
-
-func TestDecoderPeek(t *testing.T) {- t.Parallel()
-
- dec := pktline.NewDecoder(strings.NewReader("0005x0000"), pktline.ReadOptions{})-
- f, err := dec.PeekFrame()
- if err != nil {- t.Fatalf("PeekFrame: %v", err)- }
-
- if f.Type != pktline.PacketData || string(f.Payload) != "x" {- t.Fatalf("peek frame = %#v", f)- }
-
- f, err = dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame: %v", err)- }
-
- if f.Type != pktline.PacketData || string(f.Payload) != "x" {- t.Fatalf("read frame = %#v", f)- }
-}
--- a/format/pktline/decoder_rejects_over_maximum_length_test.go
+++ /dev/null
@@ -1,22 +1,0 @@
-package pktline_test
-
-import (
- "errors"
- "strings"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/pktline"
-)
-
-func TestDecoderRejectsOverMaximumLength(t *testing.T) {- t.Parallel()
-
- dec := pktline.NewDecoder(strings.NewReader("fffe"), pktline.ReadOptions{})- dec.SetMaxData(70000)
-
- _, err := dec.ReadFrame()
-
- if _, ok := errors.AsType[*pktline.ProtocolError](err); !ok {- t.Fatalf("got err %v, want ProtocolError", err)- }
-}
--- a/format/pktline/decoder_resync_after_over_max_data_test.go
+++ /dev/null
@@ -1,51 +1,0 @@
-package pktline_test
-
-import (
- "bufio"
- "bytes"
- "errors"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/pktline"
-)
-
-func TestDecoderResyncAfterOverMaxData(t *testing.T) {- t.Parallel()
-
- var b bytes.Buffer
-
- bw := bufio.NewWriter(&b)
- enc := pktline.NewEncoder(bw)
-
- err := enc.WriteData([]byte("abcd"))- if err != nil {- t.Fatalf("WriteData #1: %v", err)- }
-
- err = enc.WriteData([]byte("z"))- if err != nil {- t.Fatalf("WriteData #2: %v", err)- }
-
- err = enc.FlushIO()
- if err != nil {- t.Fatalf("FlushIO: %v", err)- }
-
- dec := pktline.NewDecoder(bytes.NewReader(b.Bytes()), pktline.ReadOptions{})- dec.SetMaxData(1)
-
- _, err = dec.ReadFrame()
- if !errors.Is(err, pktline.ErrTooLarge) {- t.Fatalf("got err %v, want ErrTooLarge", err)- }
-
- f, err := dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame #2: %v", err)- }
-
- if f.Type != pktline.PacketData || string(f.Payload) != "z" {- t.Fatalf("got frame %#v, want data z", f)- }
-}
--- a/format/pktline/decoder_resync_after_over_wire_max_test.go
+++ /dev/null
@@ -1,37 +1,0 @@
-package pktline_test
-
-import (
- "bytes"
- "errors"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/pktline"
-)
-
-func TestDecoderResyncAfterOverWireMax(t *testing.T) {- t.Parallel()
-
- var b bytes.Buffer
-
- _, _ = b.WriteString("ffff")- _, _ = b.Write(bytes.Repeat([]byte{'a'}, 65531))- _, _ = b.WriteString("0005z")-
- dec := pktline.NewDecoder(bytes.NewReader(b.Bytes()), pktline.ReadOptions{})- dec.SetMaxData(70000)
-
- _, err := dec.ReadFrame()
-
- if _, ok := errors.AsType[*pktline.ProtocolError](err); !ok {- t.Fatalf("got err %v, want ProtocolError", err)- }
-
- f, err := dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame #2: %v", err)- }
-
- if f.Type != pktline.PacketData || string(f.Payload) != "z" {- t.Fatalf("got frame %#v, want data z", f)- }
-}
--- a/format/pktline/decoder_unexpected_eof_test.go
+++ /dev/null
@@ -1,21 +1,0 @@
-package pktline_test
-
-import (
- "errors"
- "io"
- "strings"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/pktline"
-)
-
-func TestDecoderUnexpectedEOF(t *testing.T) {- t.Parallel()
-
- dec := pktline.NewDecoder(strings.NewReader("0006a"), pktline.ReadOptions{})-
- _, err := dec.ReadFrame()
- if !errors.Is(err, io.ErrUnexpectedEOF) {- t.Fatalf("got err %v, want io.ErrUnexpectedEOF", err)- }
-}
--- a/format/pktline/doc.go
+++ /dev/null
@@ -1,2 +1,0 @@
-// Package pktline implements the pkt-line format specified in gitprotocol-common(5).
-package pktline
--- a/format/pktline/encode_length_header_test.go
+++ /dev/null
@@ -1,28 +1,0 @@
-package pktline_test
-
-import (
- "errors"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/pktline"
-)
-
-func TestEncodeLengthHeader(t *testing.T) {- t.Parallel()
-
- var hdr [4]byte
-
- err := pktline.EncodeLengthHeader(&hdr, 4)
- if err != nil {- t.Fatalf("unexpected error: %v", err)- }
-
- if got := string(hdr[:]); got != "0004" {- t.Fatalf("got %q, want %q", got, "0004")- }
-
- err = pktline.EncodeLengthHeader(&hdr, pktline.LargePacketMax+1)
- if !errors.Is(err, pktline.ErrInvalidLength) {- t.Fatalf("got err %v, want ErrInvalidLength", err)- }
-}
--- a/format/pktline/encoder.go
+++ /dev/null
@@ -1,145 +1,0 @@
-package pktline
-
-import (
- "fmt"
- "io"
-)
-
-// WriteFlusher is the output transport contract required by Encoder.
-//
-// Write emits framed bytes and Flush pushes buffered transport state.
-type WriteFlusher interface {- io.Writer
- Flush() error
-}
-
-// Encoder writes pkt-line frames to a flush-capable output transport.
-//
-// It writes exactly one frame per method call and does not auto-chunk data.
-type Encoder struct {- w WriteFlusher
- maxData int
-}
-
-// NewEncoder creates an encoder over w.
-func NewEncoder(w WriteFlusher) *Encoder {- return &Encoder{- w: w,
- maxData: LargePacketDataMax,
- }
-}
-
-// SetMaxData sets the maximum payload size accepted by WriteData.
-//
-// Non-positive n resets to LargePacketDataMax.
-func (e *Encoder) SetMaxData(n int) {- if n <= 0 {- e.maxData = LargePacketDataMax
-
- return
- }
-
- e.maxData = n
-}
-
-func writeAll(w io.Writer, b []byte) error {- for len(b) > 0 {- n, err := w.Write(b)
- if err != nil {- return err
- }
-
- if n <= 0 {- return io.ErrShortWrite
- }
-
- b = b[n:]
- }
-
- return nil
-}
-
-// WriteData writes one data frame.
-//
-// Empty payload is encoded as 0004.
-func (e *Encoder) WriteData(p []byte) error {- maxData := e.effectiveMaxData()
- if len(p) > maxData {- return fmt.Errorf("%w: %d > %d", ErrTooLarge, len(p), maxData)- }
-
- var hdr [4]byte
-
- err := EncodeLengthHeader(&hdr, len(p)+4)
- if err != nil {- return err
- }
-
- err = writeAll(e.w, hdr[:])
- if err != nil {- return err
- }
-
- return writeAll(e.w, p)
-}
-
-// WriteString writes one data frame containing s and returns len(s) on success.
-func (e *Encoder) WriteString(s string) (int, error) {- err := e.WriteData([]byte(s))
- if err != nil {- return 0, err
- }
-
- return len(s), nil
-}
-
-// WriteFlush writes control frame 0000 (flush-pkt).
-func (e *Encoder) WriteFlush() error {- return e.writeControl(0)
-}
-
-// WriteDelim writes control frame 0001 (delim-pkt).
-func (e *Encoder) WriteDelim() error {- return e.writeControl(1)
-}
-
-// WriteResponseEnd writes control frame 0002 (response-end-pkt).
-func (e *Encoder) WriteResponseEnd() error {- return e.writeControl(2)
-}
-
-// FlushIO flushes buffered output in the underlying transport.
-//
-// FlushIO does not emit any pkt-line control frame.
-func (e *Encoder) FlushIO() error {- return e.w.Flush()
-}
-
-// WriteFlushAndFlushIO writes a flush-pkt (0000) then flushes transport I/O.
-func (e *Encoder) WriteFlushAndFlushIO() error {- err := e.WriteFlush()
- if err != nil {- return err
- }
-
- return e.FlushIO()
-}
-
-func (e *Encoder) writeControl(n int) error {- var hdr [4]byte
-
- err := EncodeLengthHeader(&hdr, n)
- if err != nil {- return err
- }
-
- return writeAll(e.w, hdr[:])
-}
-
-func (e *Encoder) effectiveMaxData() int {- if e.maxData <= 0 || e.maxData > LargePacketDataMax {- return LargePacketDataMax
- }
-
- return e.maxData
-}
--- a/format/pktline/encoder_buffered_flush_and_f_flush_test.go
+++ /dev/null
@@ -1,50 +1,0 @@
-package pktline_test
-
-import (
- "bufio"
- "bytes"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/pktline"
-)
-
-func TestEncoderBufferedFlushAndFFlush(t *testing.T) {- t.Parallel()
-
- var out bytes.Buffer
-
- bw := bufio.NewWriter(&out)
- enc := pktline.NewEncoder(bw)
-
- err := enc.WriteData([]byte("x"))- if err != nil {- t.Fatalf("WriteData: %v", err)- }
-
- if out.Len() != 0 {- t.Fatalf("unexpected immediate output: %q", out.String())- }
-
- err = enc.FlushIO()
- if err != nil {- t.Fatalf("FlushIO: %v", err)- }
-
- if out.String() != "0005x" {- t.Fatalf("got %q, want %q", out.String(), "0005x")- }
-
- out.Reset()
- bw = bufio.NewWriter(&out)
-
- enc = pktline.NewEncoder(bw)
-
- err = enc.WriteFlushAndFlushIO()
- if err != nil {- t.Fatalf("WriteFlushAndFlushIO: %v", err)- }
-
- if out.String() != "0000" {- t.Fatalf("got %q, want %q", out.String(), "0000")- }
-}
--- a/format/pktline/encoder_buffered_flush_behavior_test.go
+++ /dev/null
@@ -1,86 +1,0 @@
-package pktline_test
-
-import (
- "bufio"
- "bytes"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/pktline"
-)
-
-func TestEncoderBufferedFlushBehavior(t *testing.T) {- t.Parallel()
-
- var out bytes.Buffer
-
- bw := bufio.NewWriter(&out)
- enc := pktline.NewEncoder(bw)
-
- err := enc.WriteData([]byte("hello"))- if err != nil {- t.Fatalf("WriteData: %v", err)- }
-
- err = enc.WriteFlush()
- if err != nil {- t.Fatalf("WriteFlush: %v", err)- }
-
- if out.Len() != 0 {- t.Fatalf("WriteFlush should not flush I/O, got %q", out.String())- }
-
- err = enc.FlushIO()
- if err != nil {- t.Fatalf("FlushIO: %v", err)- }
-
- if got, want := out.String(), "0009hello0000"; got != want {- t.Fatalf("got %q, want %q", got, want)- }
-
- out.Reset()
- bw = bufio.NewWriter(&out)
- enc = pktline.NewEncoder(bw)
-
- err = enc.WriteData([]byte("ok"))- if err != nil {- t.Fatalf("WriteData: %v", err)- }
-
- err = enc.WriteFlush()
- if err != nil {- t.Fatalf("WriteFlush: %v", err)- }
-
- if out.Len() != 0 {- t.Fatalf("WriteFlush should not flush I/O, got %q", out.String())- }
-
- err = enc.FlushIO()
- if err != nil {- t.Fatalf("FlushIO: %v", err)- }
-
- if got, want := out.String(), "0006ok0000"; got != want {- t.Fatalf("got %q, want %q", got, want)- }
-
- out.Reset()
- bw = bufio.NewWriter(&out)
- enc = pktline.NewEncoder(bw)
-
- err = enc.WriteData([]byte("yo"))- if err != nil {- t.Fatalf("WriteData: %v", err)- }
-
- err = enc.WriteFlushAndFlushIO()
- if err != nil {- t.Fatalf("WriteFlushAndFlushIO: %v", err)- }
-
- if got, want := out.String(), "0006yo0000"; got != want {- t.Fatalf("got %q, want %q", got, want)- }
-}
--- a/format/pktline/encoder_set_max_data_cannot_exceed_wire_limit_test.go
+++ /dev/null
@@ -1,26 +1,0 @@
-package pktline_test
-
-import (
- "bufio"
- "bytes"
- "errors"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/pktline"
-)
-
-func TestEncoderSetMaxDataCannotExceedWireLimit(t *testing.T) {- t.Parallel()
-
- var out bytes.Buffer
-
- bw := bufio.NewWriter(&out)
-
- enc := pktline.NewEncoder(bw)
- enc.SetMaxData(pktline.LargePacketDataMax + 100)
-
- err := enc.WriteData(bytes.Repeat([]byte{'x'}, pktline.LargePacketDataMax+1))- if !errors.Is(err, pktline.ErrTooLarge) {- t.Fatalf("got err %v, want ErrTooLarge", err)- }
-}
--- a/format/pktline/encoder_writes_frames_test.go
+++ /dev/null
@@ -1,51 +1,0 @@
-package pktline_test
-
-import (
- "bufio"
- "bytes"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/pktline"
-)
-
-func TestEncoderWritesFrames(t *testing.T) {- t.Parallel()
-
- var b bytes.Buffer
-
- bw := bufio.NewWriter(&b)
-
- enc := pktline.NewEncoder(bw)
-
- err := enc.WriteData([]byte("hi"))- if err != nil {- t.Fatalf("WriteData: %v", err)- }
-
- err = enc.WriteFlush()
- if err != nil {- t.Fatalf("WriteFlush: %v", err)- }
-
- err = enc.WriteDelim()
- if err != nil {- t.Fatalf("WriteDelim: %v", err)- }
-
- err = enc.WriteResponseEnd()
- if err != nil {- t.Fatalf("WriteResponseEnd: %v", err)- }
-
- err = enc.FlushIO()
- if err != nil {- t.Fatalf("FlushIO: %v", err)- }
-
- got := b.String()
-
- want := "0006hi000000010002"
- if got != want {- t.Fatalf("got %q, want %q", got, want)- }
-}
--- a/format/pktline/errors.go
+++ /dev/null
@@ -1,31 +1,0 @@
-package pktline
-
-import "errors"
-
-var (
- // ErrInvalidLength indicates a malformed 4-byte hexadecimal length header.
- ErrInvalidLength = errors.New("pktline: invalid length header")- // ErrTooLarge indicates a payload exceeds configured packet data limits.
- ErrTooLarge = errors.New("pktline: payload too large")-)
-
-// ProtocolError reports invalid pkt-line framing.
-//
-// It is returned for protocol violations such as invalid control values
-// (for example 0003) or non-hex length headers.
-type ProtocolError struct {- Header [4]byte
- Reason string
-}
-
-func (e *ProtocolError) Error() string {- if e == nil {- return "<nil>"
- }
-
- if e.Reason == "" {- return "pktline: protocol error"
- }
-
- return "pktline: protocol error: " + e.Reason
-}
--- a/format/pktline/frame.go
+++ /dev/null
@@ -1,10 +1,0 @@
-package pktline
-
-// Frame is one decoded pkt-line frame.
-//
-// For PacketData, Payload holds frame bytes (possibly empty for 0004).
-// For control frames, Payload is nil.
-type Frame struct {- Type PacketType
- Payload []byte
-}
--- a/format/pktline/header.go
+++ /dev/null
@@ -1,57 +1,0 @@
-package pktline
-
-import "fmt"
-
-func hexval(b byte) int {- switch {- case b >= '0' && b <= '9':
- return int(b - '0')
- case b >= 'a' && b <= 'f':
- return int(b-'a') + 10
- case b >= 'A' && b <= 'F':
- return int(b-'A') + 10
- default:
- return -1
- }
-}
-
-// ParseLengthHeader parses a 4-byte hexadecimal pkt-line length header.
-//
-// The returned value is the full on-wire packet size, including the 4-byte
-// header. Semantic interpretation (data/control/error) is done by Decoder.
-//
-// The 4-byte header is only an actual length when above or equal to 4.
-// Otherwise, it indicates some control packet.
-func ParseLengthHeader(h [4]byte) (int, error) {- a := hexval(h[0])
- b := hexval(h[1])
- c := hexval(h[2])
- d := hexval(h[3])
-
- if a < 0 || b < 0 || c < 0 || d < 0 {- return 0, fmt.Errorf("%w: %q", ErrInvalidLength, string(h[:]))- }
-
- return (a << 12) | (b << 8) | (c << 4) | d, nil
-}
-
-// EncodeLengthHeader encodes n as a 4-byte hexadecimal pkt-line header.
-//
-// n is the full on-wire packet size including the 4-byte header.
-//
-// The 4-byte header is only an actual length when above or equal to 4.
-// Otherwise, it indicates some control packet.
-func EncodeLengthHeader(dst *[4]byte, n int) error {- if n < 0 || n > LargePacketMax {- return fmt.Errorf("%w: %d", ErrInvalidLength, n)- }
-
- const hex = "0123456789abcdef"
-
- dst[0] = hex[(n>>12)&0xf]
- dst[1] = hex[(n>>8)&0xf]
- dst[2] = hex[(n>>4)&0xf]
- dst[3] = hex[n&0xf]
-
- return nil
-}
--- a/format/pktline/parse_length_header_test.go
+++ /dev/null
@@ -1,26 +1,0 @@
-package pktline_test
-
-import (
- "errors"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/pktline"
-)
-
-func TestParseLengthHeader(t *testing.T) {- t.Parallel()
-
- n, err := pktline.ParseLengthHeader([4]byte{'0', '0', '0', '4'})- if err != nil {- t.Fatalf("unexpected error: %v", err)- }
-
- if n != 4 {- t.Fatalf("got %d, want 4", n)- }
-
- _, err = pktline.ParseLengthHeader([4]byte{'0', '0', '0', 'x'})- if !errors.Is(err, pktline.ErrInvalidLength) {- t.Fatalf("got err %v, want ErrInvalidLength", err)- }
-}
--- a/format/pktline/type.go
+++ /dev/null
@@ -1,15 +1,0 @@
-package pktline
-
-// PacketType identifies the kind of pkt-line frame.
-type PacketType uint8
-
-const (
- // PacketData is a regular data frame whose payload is application-defined.
- PacketData PacketType = iota
- // PacketFlush is control frame 0000 and marks end of a message.
- PacketFlush
- // PacketDelim is control frame 0001 and separates sections in protocol v2.
- PacketDelim
- // PacketResponseEnd is control frame 0002 and marks response end on stateless v2 transports.
- PacketResponseEnd
-)
--- a/format/sideband64k/append.go
+++ /dev/null
@@ -1,40 +1,0 @@
-package sideband64k
-
-import (
- "fmt"
-
- "codeberg.org/lindenii/furgit/format/pktline"
-)
-
-// AppendBand appends one side-band-64k data frame to dst.
-func AppendBand(dst []byte, band Band, payload []byte) ([]byte, error) {- if !validBand(band) {- return dst, fmt.Errorf("%w: %d", ErrInvalidBand, band)- }
-
- maxData := effectiveMaxData(DataMax)
- if len(payload) > maxData {- return dst, fmt.Errorf("%w: %d > %d", ErrTooLarge, len(payload), maxData)- }
-
- framed := make([]byte, len(payload)+1)
- framed[0] = byte(band)
- copy(framed[1:], payload)
-
- return pktline.AppendData(dst, framed)
-}
-
-// AppendData appends one band-1 data frame to dst.
-func AppendData(dst, payload []byte) ([]byte, error) {- return AppendBand(dst, BandData, payload)
-}
-
-// AppendProgress appends one band-2 progress frame to dst.
-func AppendProgress(dst, payload []byte) ([]byte, error) {- return AppendBand(dst, BandProgress, payload)
-}
-
-// AppendError appends one band-3 error frame to dst.
-func AppendError(dst, payload []byte) ([]byte, error) {- return AppendBand(dst, BandError, payload)
-}
--- a/format/sideband64k/append_helpers_test.go
+++ /dev/null
@@ -1,30 +1,0 @@
-package sideband64k_test
-
-import (
- "testing"
-
- "codeberg.org/lindenii/furgit/format/sideband64k"
-)
-
-func TestAppendHelpers(t *testing.T) {- t.Parallel()
-
- out, err := sideband64k.AppendData(nil, []byte("a"))- if err != nil {- t.Fatalf("AppendData: %v", err)- }
-
- out, err = sideband64k.AppendProgress(out, []byte("b"))- if err != nil {- t.Fatalf("AppendProgress: %v", err)- }
-
- out, err = sideband64k.AppendError(out, []byte("c"))- if err != nil {- t.Fatalf("AppendError: %v", err)- }
-
- if got, want := string(out), "0006\x01a0006\x02b0006\x03c"; got != want {- t.Fatalf("got %q, want %q", got, want)- }
-}
--- a/format/sideband64k/append_preserves_dst_on_error_test.go
+++ /dev/null
@@ -1,34 +1,0 @@
-package sideband64k_test
-
-import (
- "bytes"
- "errors"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/sideband64k"
-)
-
-func TestAppendBandPreservesDstOnError(t *testing.T) {- t.Parallel()
-
- orig := []byte("seed")- dst := append([]byte(nil), orig...)
-
- out, err := sideband64k.AppendBand(dst, 4, []byte("x"))- if !errors.Is(err, sideband64k.ErrInvalidBand) {- t.Fatalf("got err %v, want ErrInvalidBand", err)- }
-
- if !bytes.Equal(out, orig) {- t.Fatalf("got %q, want %q", string(out), string(orig))- }
-
- out, err = sideband64k.AppendData(dst, bytes.Repeat([]byte{'x'}, sideband64k.DataMax+1))- if !errors.Is(err, sideband64k.ErrTooLarge) {- t.Fatalf("got err %v, want ErrTooLarge", err)- }
-
- if !bytes.Equal(out, orig) {- t.Fatalf("got %q, want %q", string(out), string(orig))- }
-}
--- a/format/sideband64k/band.go
+++ /dev/null
@@ -1,13 +1,0 @@
-package sideband64k
-
-// Band identifies the sideband stream within a pkt-line data frame.
-type Band uint8
-
-const (
- // BandData carries primary payload bytes.
- BandData Band = 1
- // BandProgress carries progress or informational messages.
- BandProgress Band = 2
- // BandError carries fatal error messages.
- BandError Band = 3
-)
--- a/format/sideband64k/chunk_writer.go
+++ /dev/null
@@ -1,64 +1,0 @@
-package sideband64k
-
-import "io"
-
-// ChunkWriter packetizes arbitrary stream bytes into side-band-64k data frames
-// for one fixed band.
-//
-// It never writes control packets automatically.
-type ChunkWriter struct {- enc *Encoder
- band Band
-}
-
-// NewChunkWriter creates a chunking adapter over enc for one band.
-func NewChunkWriter(enc *Encoder, band Band) *ChunkWriter {- return &ChunkWriter{enc: enc, band: band}-}
-
-// Write splits p into sideband frames not larger than enc's maxData.
-func (cw *ChunkWriter) Write(p []byte) (int, error) {- total := 0
- maxData := cw.enc.effectiveMaxData()
-
- for len(p) > 0 {- n := min(len(p), maxData)
-
- err := cw.enc.WriteBand(cw.band, p[:n])
- if err != nil {- return total, err
- }
-
- total += n
- p = p[n:]
- }
-
- return total, nil
-}
-
-// ReadFrom reads from r and writes sideband frames to the encoder.
-func (cw *ChunkWriter) ReadFrom(r io.Reader) (int64, error) {- buf := make([]byte, cw.enc.effectiveMaxData())
-
- var total int64
-
- for {- n, err := r.Read(buf)
- if n > 0 {- werr := cw.enc.WriteBand(cw.band, buf[:n])
- if werr != nil {- return total, werr
- }
-
- total += int64(n)
- }
-
- if err != nil {- if err == io.EOF {- return total, nil
- }
-
- return total, err
- }
- }
-}
--- a/format/sideband64k/chunk_writer_write_and_read_from_test.go
+++ /dev/null
@@ -1,60 +1,0 @@
-package sideband64k_test
-
-import (
- "bufio"
- "bytes"
- "strings"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/sideband64k"
-)
-
-func TestChunkWriterWriteAndReadFrom(t *testing.T) {- t.Parallel()
-
- var out bytes.Buffer
-
- bw := bufio.NewWriter(&out)
- enc := sideband64k.NewEncoder(bw)
- enc.SetMaxData(3)
-
- cw := sideband64k.NewChunkWriter(enc, sideband64k.BandProgress)
-
- n, err := cw.Write([]byte("abcdefg"))- if err != nil {- t.Fatalf("Write: %v", err)- }
-
- if n != 7 {- t.Fatalf("Write n=%d, want 7", n)- }
-
- err = enc.FlushIO()
- if err != nil {- t.Fatalf("FlushIO: %v", err)- }
-
- if got, want := out.String(), "0008\x02abc0008\x02def0006\x02g"; got != want {- t.Fatalf("got %q, want %q", got, want)- }
-
- out.Reset()
-
- rn, err := cw.ReadFrom(strings.NewReader("wxyz"))- if err != nil {- t.Fatalf("ReadFrom: %v", err)- }
-
- if rn != 4 {- t.Fatalf("ReadFrom n=%d, want 4", rn)- }
-
- err = enc.FlushIO()
- if err != nil {- t.Fatalf("FlushIO: %v", err)- }
-
- if got, want := out.String(), "0008\x02wxy0006\x02z"; got != want {- t.Fatalf("got %q, want %q", got, want)- }
-}
--- a/format/sideband64k/constants.go
+++ /dev/null
@@ -1,10 +1,0 @@
-package sideband64k
-
-import "codeberg.org/lindenii/furgit/format/pktline"
-
-const (
- // PacketMax is the maximum on-wire pkt-line size used by side-band-64k.
- PacketMax = pktline.LargePacketMax
- // DataMax is the maximum sideband payload size excluding the 1-byte band designator.
- DataMax = pktline.LargePacketDataMax - 1
-)
--- a/format/sideband64k/decoder.go
+++ /dev/null
@@ -1,158 +1,0 @@
-package sideband64k
-
-import (
- "fmt"
- "io"
-
- "codeberg.org/lindenii/furgit/format/pktline"
-)
-
-// ReadOptions controls sideband decoding behavior.
-type ReadOptions struct {- // ChompLF removes one trailing '\n' from FrameData payloads only.
- ChompLF bool
-}
-
-// Decoder reads side-band-64k frames from an io.Reader.
-//
-// It preserves frame boundaries and supports one-frame lookahead via
-// PeekFrame.
-type Decoder struct {- dec *pktline.Decoder
- maxData int
- opts ReadOptions
-
- peeked bool
- peek Frame
- peekErr error
-}
-
-// NewDecoder creates a decoder over r.
-func NewDecoder(r io.Reader, opts ReadOptions) *Decoder {- d := &Decoder{- dec: pktline.NewDecoder(r, pktline.ReadOptions{}),- maxData: DataMax,
- opts: opts,
- }
- d.dec.SetMaxData(pktline.LargePacketDataMax)
-
- return d
-}
-
-// SetMaxData sets maximum payload size accepted for one sideband data packet.
-//
-// Non-positive n resets to DataMax.
-func (d *Decoder) SetMaxData(n int) {- if n <= 0 {- d.maxData = DataMax
-
- return
- }
-
- d.maxData = n
-}
-
-// ReadFrame reads one frame.
-func (d *Decoder) ReadFrame() (Frame, error) {- if d.peeked {- d.peeked = false
-
- return cloneFrame(d.peek), d.peekErr
- }
-
- return d.readFrame()
-}
-
-// PeekFrame returns the next frame without consuming it.
-func (d *Decoder) PeekFrame() (Frame, error) {- if !d.peeked {- d.peek, d.peekErr = d.readFrame()
- d.peeked = true
- }
-
- return cloneFrame(d.peek), d.peekErr
-}
-
-func (d *Decoder) readFrame() (Frame, error) {- f, err := d.dec.ReadFrame()
- if err != nil {- return Frame{}, err- }
-
- switch f.Type {- case pktline.PacketFlush:
- return Frame{Type: FrameFlush}, nil- case pktline.PacketDelim:
- return Frame{Type: FrameDelim}, nil- case pktline.PacketResponseEnd:
- return Frame{Type: FrameResponseEnd}, nil- case pktline.PacketData:
- if len(f.Payload) == 0 {- return Frame{}, &ProtocolError{Reason: "missing sideband designator"}- }
-
- payload := f.Payload[1:]
- if len(payload) > d.effectiveMaxData() {- return Frame{}, fmt.Errorf("%w: %d > %d", ErrTooLarge, len(payload), d.effectiveMaxData())- }
-
- band := Band(f.Payload[0])
- if !validBand(band) {- return Frame{}, &ProtocolError{Reason: fmt.Sprintf("%v: %d", ErrInvalidBand, band)}- }
-
- payload = append([]byte(nil), payload...)
- if d.opts.ChompLF && band == BandData && len(payload) > 0 && payload[len(payload)-1] == '\n' {- payload = payload[:len(payload)-1]
- }
-
- return Frame{- Type: frameTypeForBand(band),
- Payload: payload,
- }, nil
- default:
- return Frame{}, &ProtocolError{Reason: "unknown pkt-line frame type"}- }
-}
-
-func (d *Decoder) effectiveMaxData() int {- return effectiveMaxData(d.maxData)
-}
-
-func cloneFrame(f Frame) Frame {- if f.Type == FrameFlush || f.Type == FrameDelim || f.Type == FrameResponseEnd {- return Frame{Type: f.Type}- }
-
- out := Frame{Type: f.Type}- if f.Payload != nil {- out.Payload = append([]byte(nil), f.Payload...)
- }
-
- return out
-}
-
-func validBand(band Band) bool {- return band == BandData || band == BandProgress || band == BandError
-}
-
-func frameTypeForBand(band Band) FrameType {- switch band {- case BandData:
- return FrameData
- case BandProgress:
- return FrameProgress
- case BandError:
- return FrameError
- default:
- panic("invalid sideband64k band")- }
-}
-
-func effectiveMaxData(n int) int {- if n <= 0 || n > DataMax {- return DataMax
- }
-
- return n
-}
--- a/format/sideband64k/decoder_data_control_and_keepalive_test.go
+++ /dev/null
@@ -1,78 +1,0 @@
-package sideband64k_test
-
-import (
- "strings"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/sideband64k"
-)
-
-func TestDecoderDataControlAndKeepalive(t *testing.T) {- t.Parallel()
-
- input := "0007\x01a\n0005\x010007\x02p\n0007\x03e\n000100020000"
- dec := sideband64k.NewDecoder(strings.NewReader(input), sideband64k.ReadOptions{ChompLF: true})-
- f, err := dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame #1: %v", err)- }
-
- if f.Type != sideband64k.FrameData || string(f.Payload) != "a" {- t.Fatalf("frame #1 = %#v", f)- }
-
- f, err = dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame #2: %v", err)- }
-
- if f.Type != sideband64k.FrameData || len(f.Payload) != 0 {- t.Fatalf("frame #2 = %#v, want empty data", f)- }
-
- f, err = dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame #3: %v", err)- }
-
- if f.Type != sideband64k.FrameProgress || string(f.Payload) != "p\n" {- t.Fatalf("frame #3 = %#v", f)- }
-
- f, err = dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame #4: %v", err)- }
-
- if f.Type != sideband64k.FrameError || string(f.Payload) != "e\n" {- t.Fatalf("frame #4 = %#v", f)- }
-
- f, err = dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame #5: %v", err)- }
-
- if f.Type != sideband64k.FrameDelim {- t.Fatalf("frame #5 type = %v, want FrameDelim", f.Type)- }
-
- f, err = dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame #6: %v", err)- }
-
- if f.Type != sideband64k.FrameResponseEnd {- t.Fatalf("frame #6 type = %v, want FrameResponseEnd", f.Type)- }
-
- f, err = dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame #7: %v", err)- }
-
- if f.Type != sideband64k.FrameFlush {- t.Fatalf("frame #7 type = %v, want FrameFlush", f.Type)- }
-}
--- a/format/sideband64k/decoder_invalid_band_test.go
+++ /dev/null
@@ -1,20 +1,0 @@
-package sideband64k_test
-
-import (
- "errors"
- "strings"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/sideband64k"
-)
-
-func TestDecoderInvalidBand(t *testing.T) {- t.Parallel()
-
- dec := sideband64k.NewDecoder(strings.NewReader("0005\x04"), sideband64k.ReadOptions{})- _, err := dec.ReadFrame()
-
- if _, ok := errors.AsType[*sideband64k.ProtocolError](err); !ok {- t.Fatalf("got err %v, want ProtocolError", err)- }
-}
--- a/format/sideband64k/decoder_invalid_empty_payload_test.go
+++ /dev/null
@@ -1,20 +1,0 @@
-package sideband64k_test
-
-import (
- "errors"
- "strings"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/sideband64k"
-)
-
-func TestDecoderInvalidEmptyPayload(t *testing.T) {- t.Parallel()
-
- dec := sideband64k.NewDecoder(strings.NewReader("0004"), sideband64k.ReadOptions{})- _, err := dec.ReadFrame()
-
- if _, ok := errors.AsType[*sideband64k.ProtocolError](err); !ok {- t.Fatalf("got err %v, want ProtocolError", err)- }
-}
--- a/format/sideband64k/decoder_malformed_pktline_test.go
+++ /dev/null
@@ -1,32 +1,0 @@
-package sideband64k_test
-
-import (
- "errors"
- "strings"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/pktline"
- "codeberg.org/lindenii/furgit/format/sideband64k"
-)
-
-func TestDecoderInvalid0003(t *testing.T) {- t.Parallel()
-
- dec := sideband64k.NewDecoder(strings.NewReader("0003"), sideband64k.ReadOptions{})- _, err := dec.ReadFrame()
-
- if _, ok := errors.AsType[*pktline.ProtocolError](err); !ok {- t.Fatalf("got err %v, want pktline.ProtocolError", err)- }
-}
-
-func TestDecoderRejectsOverMaximumLength(t *testing.T) {- t.Parallel()
-
- dec := sideband64k.NewDecoder(strings.NewReader("fffe"), sideband64k.ReadOptions{})- _, err := dec.ReadFrame()
-
- if _, ok := errors.AsType[*pktline.ProtocolError](err); !ok {- t.Fatalf("got err %v, want pktline.ProtocolError", err)- }
-}
--- a/format/sideband64k/decoder_partial_read_test.go
+++ /dev/null
@@ -1,32 +1,0 @@
-package sideband64k_test
-
-import (
- "testing"
-
- "codeberg.org/lindenii/furgit/format/sideband64k"
-)
-
-func TestDecoderHandlesPartialReads(t *testing.T) {- t.Parallel()
-
- r := &byteReader{data: []byte("0007\x02ok0000")}- dec := sideband64k.NewDecoder(r, sideband64k.ReadOptions{})-
- f, err := dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame #1: %v", err)- }
-
- if f.Type != sideband64k.FrameProgress || string(f.Payload) != "ok" {- t.Fatalf("frame #1 = %#v", f)- }
-
- f, err = dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame #2: %v", err)- }
-
- if f.Type != sideband64k.FrameFlush {- t.Fatalf("frame #2 = %#v", f)- }
-}
--- a/format/sideband64k/decoder_peek_test.go
+++ /dev/null
@@ -1,34 +1,0 @@
-package sideband64k_test
-
-import (
- "strings"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/sideband64k"
-)
-
-func TestDecoderPeek(t *testing.T) {- t.Parallel()
-
- dec := sideband64k.NewDecoder(strings.NewReader("0006\x01x0000"), sideband64k.ReadOptions{})-
- f, err := dec.PeekFrame()
- if err != nil {- t.Fatalf("PeekFrame: %v", err)- }
-
- if f.Type != sideband64k.FrameData || string(f.Payload) != "x" {- t.Fatalf("peek frame = %#v", f)- }
-
- f.Payload[0] = 'y'
-
- f, err = dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame: %v", err)- }
-
- if f.Type != sideband64k.FrameData || string(f.Payload) != "x" {- t.Fatalf("read frame = %#v", f)- }
-}
--- a/format/sideband64k/decoder_resync_after_over_max_data_test.go
+++ /dev/null
@@ -1,51 +1,0 @@
-package sideband64k_test
-
-import (
- "bufio"
- "bytes"
- "errors"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/sideband64k"
-)
-
-func TestDecoderResyncAfterOverMaxData(t *testing.T) {- t.Parallel()
-
- var b bytes.Buffer
-
- bw := bufio.NewWriter(&b)
- enc := sideband64k.NewEncoder(bw)
-
- err := enc.WriteData([]byte("abcd"))- if err != nil {- t.Fatalf("WriteData #1: %v", err)- }
-
- err = enc.WriteData([]byte("z"))- if err != nil {- t.Fatalf("WriteData #2: %v", err)- }
-
- err = enc.FlushIO()
- if err != nil {- t.Fatalf("FlushIO: %v", err)- }
-
- dec := sideband64k.NewDecoder(bytes.NewReader(b.Bytes()), sideband64k.ReadOptions{})- dec.SetMaxData(1)
-
- _, err = dec.ReadFrame()
- if !errors.Is(err, sideband64k.ErrTooLarge) {- t.Fatalf("got err %v, want ErrTooLarge", err)- }
-
- f, err := dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame #2: %v", err)- }
-
- if f.Type != sideband64k.FrameData || string(f.Payload) != "z" {- t.Fatalf("got frame %#v, want data z", f)- }
-}
--- a/format/sideband64k/decoder_resync_after_over_wire_max_test.go
+++ /dev/null
@@ -1,37 +1,0 @@
-package sideband64k_test
-
-import (
- "bytes"
- "errors"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/pktline"
- "codeberg.org/lindenii/furgit/format/sideband64k"
-)
-
-func TestDecoderResyncAfterOverWireMax(t *testing.T) {- t.Parallel()
-
- var b bytes.Buffer
-
- _, _ = b.WriteString("ffff")- _, _ = b.Write(bytes.Repeat([]byte{'a'}, 65531))- _, _ = b.WriteString("0006\x01z")-
- dec := sideband64k.NewDecoder(bytes.NewReader(b.Bytes()), sideband64k.ReadOptions{})-
- _, err := dec.ReadFrame()
-
- if _, ok := errors.AsType[*pktline.ProtocolError](err); !ok {- t.Fatalf("got err %v, want pktline.ProtocolError", err)- }
-
- f, err := dec.ReadFrame()
- if err != nil {- t.Fatalf("ReadFrame #2: %v", err)- }
-
- if f.Type != sideband64k.FrameData || string(f.Payload) != "z" {- t.Fatalf("got frame %#v, want data z", f)- }
-}
--- a/format/sideband64k/decoder_unexpected_eof_test.go
+++ /dev/null
@@ -1,21 +1,0 @@
-package sideband64k_test
-
-import (
- "errors"
- "io"
- "strings"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/sideband64k"
-)
-
-func TestDecoderUnexpectedEOF(t *testing.T) {- t.Parallel()
-
- dec := sideband64k.NewDecoder(strings.NewReader("0006\x01"), sideband64k.ReadOptions{})-
- _, err := dec.ReadFrame()
- if !errors.Is(err, io.ErrUnexpectedEOF) {- t.Fatalf("got err %v, want io.ErrUnexpectedEOF", err)- }
-}
--- a/format/sideband64k/doc.go
+++ /dev/null
@@ -1,2 +1,0 @@
-// Package sideband64k implements Git side-band-64k multiplexing over pkt-line.
-package sideband64k
--- a/format/sideband64k/encoder.go
+++ /dev/null
@@ -1,98 +1,0 @@
-package sideband64k
-
-import (
- "fmt"
-
- "codeberg.org/lindenii/furgit/format/pktline"
-)
-
-// Encoder writes side-band-64k frames to a flush-capable output transport.
-//
-// It writes exactly one frame per method call and does not auto-chunk data.
-type Encoder struct {- enc *pktline.Encoder
- maxData int
-}
-
-// NewEncoder creates an encoder over w.
-func NewEncoder(w pktline.WriteFlusher) *Encoder {- return &Encoder{- enc: pktline.NewEncoder(w),
- maxData: DataMax,
- }
-}
-
-// SetMaxData sets the maximum payload size accepted by WriteBand.
-//
-// Non-positive n resets to DataMax.
-func (e *Encoder) SetMaxData(n int) {- if n <= 0 {- e.maxData = DataMax
-
- return
- }
-
- e.maxData = n
-}
-
-// WriteBand writes one side-band-64k data frame for the given band.
-func (e *Encoder) WriteBand(band Band, p []byte) error {- if !validBand(band) {- return fmt.Errorf("%w: %d", ErrInvalidBand, band)- }
-
- maxData := e.effectiveMaxData()
- if len(p) > maxData {- return fmt.Errorf("%w: %d > %d", ErrTooLarge, len(p), maxData)- }
-
- framed := make([]byte, len(p)+1)
- framed[0] = byte(band)
- copy(framed[1:], p)
-
- return e.enc.WriteData(framed)
-}
-
-// WriteData writes one band-1 data frame.
-func (e *Encoder) WriteData(p []byte) error {- return e.WriteBand(BandData, p)
-}
-
-// WriteProgress writes one band-2 progress frame.
-func (e *Encoder) WriteProgress(p []byte) error {- return e.WriteBand(BandProgress, p)
-}
-
-// WriteError writes one band-3 error frame.
-func (e *Encoder) WriteError(p []byte) error {- return e.WriteBand(BandError, p)
-}
-
-// WriteFlush writes control frame 0000 (flush-pkt).
-func (e *Encoder) WriteFlush() error {- return e.enc.WriteFlush()
-}
-
-// WriteDelim writes control frame 0001 (delim-pkt).
-func (e *Encoder) WriteDelim() error {- return e.enc.WriteDelim()
-}
-
-// WriteResponseEnd writes control frame 0002 (response-end-pkt).
-func (e *Encoder) WriteResponseEnd() error {- return e.enc.WriteResponseEnd()
-}
-
-// FlushIO flushes buffered output in the underlying transport.
-func (e *Encoder) FlushIO() error {- return e.enc.FlushIO()
-}
-
-// WriteFlushAndFlushIO writes a flush-pkt (0000) then flushes transport I/O.
-func (e *Encoder) WriteFlushAndFlushIO() error {- return e.enc.WriteFlushAndFlushIO()
-}
-
-func (e *Encoder) effectiveMaxData() int {- return effectiveMaxData(e.maxData)
-}
--- a/format/sideband64k/encoder_buffered_flush_behavior_test.go
+++ /dev/null
@@ -1,59 +1,0 @@
-package sideband64k_test
-
-import (
- "bufio"
- "bytes"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/sideband64k"
-)
-
-func TestEncoderBufferedFlushBehavior(t *testing.T) {- t.Parallel()
-
- var out bytes.Buffer
-
- bw := bufio.NewWriter(&out)
- enc := sideband64k.NewEncoder(bw)
-
- err := enc.WriteData([]byte("hello"))- if err != nil {- t.Fatalf("WriteData: %v", err)- }
-
- err = enc.WriteFlush()
- if err != nil {- t.Fatalf("WriteFlush: %v", err)- }
-
- if out.Len() != 0 {- t.Fatalf("WriteFlush should not flush I/O, got %q", out.String())- }
-
- err = enc.FlushIO()
- if err != nil {- t.Fatalf("FlushIO: %v", err)- }
-
- if got, want := out.String(), "000a\x01hello0000"; got != want {- t.Fatalf("got %q, want %q", got, want)- }
-
- out.Reset()
- bw = bufio.NewWriter(&out)
- enc = sideband64k.NewEncoder(bw)
-
- err = enc.WriteData([]byte("yo"))- if err != nil {- t.Fatalf("WriteData: %v", err)- }
-
- err = enc.WriteFlushAndFlushIO()
- if err != nil {- t.Fatalf("WriteFlushAndFlushIO: %v", err)- }
-
- if got, want := out.String(), "0007\x01yo0000"; got != want {- t.Fatalf("got %q, want %q", got, want)- }
-}
--- a/format/sideband64k/encoder_partial_write_test.go
+++ /dev/null
@@ -1,46 +1,0 @@
-package sideband64k_test
-
-import (
- "errors"
- "io"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/sideband64k"
-)
-
-func TestEncoderHandlesPartialWrites(t *testing.T) {- t.Parallel()
-
- dst := &limitWriter{maxPerWrite: 2}- enc := sideband64k.NewEncoder(dst)
-
- err := enc.WriteProgress([]byte("abc"))- if err != nil {- t.Fatalf("WriteProgress: %v", err)- }
-
- err = enc.WriteFlushAndFlushIO()
- if err != nil {- t.Fatalf("WriteFlushAndFlushIO: %v", err)- }
-
- if got, want := dst.buf.String(), "0008\x02abc0000"; got != want {- t.Fatalf("got %q, want %q", got, want)- }
-
- if dst.flushes != 1 {- t.Fatalf("flushes=%d, want 1", dst.flushes)- }
-}
-
-func TestEncoderReturnsShortWrite(t *testing.T) {- t.Parallel()
-
- dst := &limitWriter{shortWrite: true}- enc := sideband64k.NewEncoder(dst)
-
- err := enc.WriteData([]byte("x"))- if !errors.Is(err, io.ErrShortWrite) {- t.Fatalf("got err %v, want io.ErrShortWrite", err)- }
-}
--- a/format/sideband64k/encoder_set_max_data_cannot_exceed_wire_limit_test.go
+++ /dev/null
@@ -1,23 +1,0 @@
-package sideband64k_test
-
-import (
- "bytes"
- "errors"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/sideband64k"
-)
-
-func TestEncoderSetMaxDataCannotExceedWireLimit(t *testing.T) {- t.Parallel()
-
- var dst limitWriter
-
- enc := sideband64k.NewEncoder(&dst)
- enc.SetMaxData(sideband64k.DataMax + 100)
-
- err := enc.WriteData(bytes.Repeat([]byte{'x'}, sideband64k.DataMax+1))- if !errors.Is(err, sideband64k.ErrTooLarge) {- t.Fatalf("got err %v, want ErrTooLarge", err)- }
-}
--- a/format/sideband64k/encoder_writes_frames_test.go
+++ /dev/null
@@ -1,58 +1,0 @@
-package sideband64k_test
-
-import (
- "bufio"
- "bytes"
- "testing"
-
- "codeberg.org/lindenii/furgit/format/sideband64k"
-)
-
-func TestEncoderWritesFrames(t *testing.T) {- t.Parallel()
-
- var b bytes.Buffer
-
- bw := bufio.NewWriter(&b)
- enc := sideband64k.NewEncoder(bw)
-
- err := enc.WriteData([]byte("hi"))- if err != nil {- t.Fatalf("WriteData: %v", err)- }
-
- err = enc.WriteProgress([]byte("ok"))- if err != nil {- t.Fatalf("WriteProgress: %v", err)- }
-
- err = enc.WriteError([]byte("no"))- if err != nil {- t.Fatalf("WriteError: %v", err)- }
-
- err = enc.WriteFlush()
- if err != nil {- t.Fatalf("WriteFlush: %v", err)- }
-
- err = enc.WriteDelim()
- if err != nil {- t.Fatalf("WriteDelim: %v", err)- }
-
- err = enc.WriteResponseEnd()
- if err != nil {- t.Fatalf("WriteResponseEnd: %v", err)- }
-
- err = enc.FlushIO()
- if err != nil {- t.Fatalf("FlushIO: %v", err)- }
-
- want := "0007\x01hi0007\x02ok0007\x03no000000010002"
- if got := b.String(); got != want {- t.Fatalf("got %q, want %q", got, want)- }
-}
--- a/format/sideband64k/errors.go
+++ /dev/null
@@ -1,27 +1,0 @@
-package sideband64k
-
-import "errors"
-
-var (
- // ErrTooLarge indicates a payload exceeds configured sideband data limits.
- ErrTooLarge = errors.New("sideband64k: payload too large")- // ErrInvalidBand indicates a data frame has an invalid sideband designator.
- ErrInvalidBand = errors.New("sideband64k: invalid band designator")-)
-
-// ProtocolError reports invalid side-band-64k framing.
-type ProtocolError struct {- Reason string
-}
-
-func (e *ProtocolError) Error() string {- if e == nil {- return "<nil>"
- }
-
- if e.Reason == "" {- return "sideband64k: protocol error"
- }
-
- return "sideband64k: protocol error: " + e.Reason
-}
--- a/format/sideband64k/frame.go
+++ /dev/null
@@ -1,12 +1,0 @@
-package sideband64k
-
-// Frame is one decoded side-band-64k frame.
-//
-// For FrameData, FrameProgress, and FrameError, Payload holds frame bytes and
-// may be empty.
-//
-// For control frames, Payload is nil.
-type Frame struct {- Type FrameType
- Payload []byte
-}
--- a/format/sideband64k/frame_type.go
+++ /dev/null
@@ -1,19 +1,0 @@
-package sideband64k
-
-// FrameType identifies the kind of decoded sideband frame.
-type FrameType uint8
-
-const (
- // FrameData carries primary payload bytes from band 1.
- FrameData FrameType = iota
- // FrameProgress carries progress bytes from band 2.
- FrameProgress
- // FrameError carries fatal error bytes from band 3.
- FrameError
- // FrameFlush is pkt-line control frame 0000.
- FrameFlush
- // FrameDelim is pkt-line control frame 0001.
- FrameDelim
- // FrameResponseEnd is pkt-line control frame 0002.
- FrameResponseEnd
-)
--- a/format/sideband64k/helpers_test.go
+++ /dev/null
@@ -1,46 +1,0 @@
-package sideband64k_test
-
-import (
- "bytes"
- "io"
-)
-
-type limitWriter struct {- buf bytes.Buffer
- maxPerWrite int
- flushes int
- shortWrite bool
-}
-
-func (w *limitWriter) Write(p []byte) (int, error) {- if w.shortWrite {- return 0, nil
- }
-
- if w.maxPerWrite > 0 && len(p) > w.maxPerWrite {- p = p[:w.maxPerWrite]
- }
-
- return w.buf.Write(p)
-}
-
-func (w *limitWriter) Flush() error {- w.flushes++
-
- return nil
-}
-
-type byteReader struct {- data []byte
-}
-
-func (r *byteReader) Read(p []byte) (int, error) {- if len(r.data) == 0 {- return 0, io.EOF
- }
-
- p[0] = r.data[0]
- r.data = r.data[1:]
-
- return 1, nil
-}
--- /dev/null
+++ b/protocol/pktline/append.go
@@ -1,0 +1,39 @@
+package pktline
+
+import "fmt"
+
+// AppendData appends one data frame to dst.
+//
+// Empty payload is encoded as 0004.
+func AppendData(dst, payload []byte) ([]byte, error) {+ if len(payload) > LargePacketDataMax {+ return dst, fmt.Errorf("%w: %d > %d", ErrTooLarge, len(payload), LargePacketDataMax)+ }
+
+ var hdr [4]byte
+
+ err := EncodeLengthHeader(&hdr, len(payload)+4)
+ if err != nil {+ return dst, err
+ }
+
+ dst = append(dst, hdr[:]...)
+ dst = append(dst, payload...)
+
+ return dst, nil
+}
+
+// AppendFlushPkt appends control frame 0000 (flush-pkt).
+func AppendFlushPkt(dst []byte) []byte {+ return append(dst, '0', '0', '0', '0')
+}
+
+// AppendDelimPkt appends control frame 0001 (delim-pkt).
+func AppendDelimPkt(dst []byte) []byte {+ return append(dst, '0', '0', '0', '1')
+}
+
+// AppendResponseEndPkt appends control frame 0002 (response-end-pkt).
+func AppendResponseEndPkt(dst []byte) []byte {+ return append(dst, '0', '0', '0', '2')
+}
--- /dev/null
+++ b/protocol/pktline/append_data_preserves_dst_on_error_test.go
@@ -1,0 +1,25 @@
+package pktline_test
+
+import (
+ "bytes"
+ "errors"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+)
+
+func TestAppendDataPreservesDstOnError(t *testing.T) {+ t.Parallel()
+
+ orig := []byte("seed")+ dst := append([]byte(nil), orig...)
+
+ out, err := pktline.AppendData(dst, bytes.Repeat([]byte{'x'}, pktline.LargePacketDataMax+1))+ if !errors.Is(err, pktline.ErrTooLarge) {+ t.Fatalf("got err %v, want ErrTooLarge", err)+ }
+
+ if !bytes.Equal(out, orig) {+ t.Fatalf("got %q, want %q", string(out), string(orig))+ }
+}
--- /dev/null
+++ b/protocol/pktline/append_helpers_test.go
@@ -1,0 +1,24 @@
+package pktline_test
+
+import (
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+)
+
+func TestAppendHelpers(t *testing.T) {+ t.Parallel()
+
+ out, err := pktline.AppendData(nil, []byte("ok"))+ if err != nil {+ t.Fatalf("AppendData: %v", err)+ }
+
+ out = pktline.AppendFlushPkt(out)
+ out = pktline.AppendDelimPkt(out)
+ out = pktline.AppendResponseEndPkt(out)
+
+ if got, want := string(out), "0006ok000000010002"; got != want {+ t.Fatalf("got %q, want %q", got, want)+ }
+}
--- /dev/null
+++ b/protocol/pktline/chunk_writer.go
@@ -1,0 +1,65 @@
+package pktline
+
+import "io"
+
+// ChunkWriter packetizes arbitrary stream bytes into data pkt-lines.
+// It never writes control packets automatically.
+type ChunkWriter struct {+ enc *Encoder
+}
+
+// NewChunkWriter creates a chunking adapter over enc.
+func NewChunkWriter(enc *Encoder) *ChunkWriter {+ return &ChunkWriter{enc: enc}+}
+
+// Write splits p into data frames not larger than enc's maxData.
+//
+// It implements io.Writer.
+func (cw *ChunkWriter) Write(p []byte) (int, error) {+ total := 0
+ maxData := cw.enc.effectiveMaxData()
+
+ for len(p) > 0 {+ n := min(len(p), maxData)
+
+ err := cw.enc.WriteData(p[:n])
+ if err != nil {+ return total, err
+ }
+
+ total += n
+ p = p[n:]
+ }
+
+ return total, nil
+}
+
+// ReadFrom reads from r and writes pkt-line data frames to the encoder.
+//
+// It implements io.ReaderFrom.
+func (cw *ChunkWriter) ReadFrom(r io.Reader) (int64, error) {+ buf := make([]byte, cw.enc.effectiveMaxData())
+
+ var total int64
+
+ for {+ n, err := r.Read(buf)
+ if n > 0 {+ werr := cw.enc.WriteData(buf[:n])
+ if werr != nil {+ return total, werr
+ }
+
+ total += int64(n)
+ }
+
+ if err != nil {+ if err == io.EOF {+ return total, nil
+ }
+
+ return total, err
+ }
+ }
+}
--- /dev/null
+++ b/protocol/pktline/chunk_writer_write_and_read_from_test.go
@@ -1,0 +1,60 @@
+package pktline_test
+
+import (
+ "bufio"
+ "bytes"
+ "strings"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+)
+
+func TestChunkWriterWriteAndReadFrom(t *testing.T) {+ t.Parallel()
+
+ var out bytes.Buffer
+
+ bw := bufio.NewWriter(&out)
+
+ enc := pktline.NewEncoder(bw)
+ enc.SetMaxData(3)
+ cw := pktline.NewChunkWriter(enc)
+
+ n, err := cw.Write([]byte("abcdefg"))+ if err != nil {+ t.Fatalf("Write: %v", err)+ }
+
+ if n != 7 {+ t.Fatalf("Write n=%d, want 7", n)+ }
+
+ err = enc.FlushIO()
+ if err != nil {+ t.Fatalf("FlushIO: %v", err)+ }
+
+ if got, want := out.String(), "0007abc0007def0005g"; got != want {+ t.Fatalf("got %q, want %q", got, want)+ }
+
+ out.Reset()
+
+ rn, err := cw.ReadFrom(strings.NewReader("wxyz"))+ if err != nil {+ t.Fatalf("ReadFrom: %v", err)+ }
+
+ if rn != 4 {+ t.Fatalf("ReadFrom n=%d, want 4", rn)+ }
+
+ err = enc.FlushIO()
+ if err != nil {+ t.Fatalf("FlushIO: %v", err)+ }
+
+ if got, want := out.String(), "0007wxy0005z"; got != want {+ t.Fatalf("got %q, want %q", got, want)+ }
+}
--- /dev/null
+++ b/protocol/pktline/constants.go
@@ -1,0 +1,12 @@
+package pktline
+
+const (
+ // DefaultPacketMax is a conservative packet size commonly used by
+ // line-oriented protocol messages.
+ DefaultPacketMax = 1000
+ // LargePacketMax is the maximum on-wire packet size including the
+ // 4-byte hexadecimal length header.
+ LargePacketMax = 65520
+ // LargePacketDataMax is the maximum payload size in one packet.
+ LargePacketDataMax = LargePacketMax - 4
+)
--- /dev/null
+++ b/protocol/pktline/decoder.go
@@ -1,0 +1,187 @@
+package pktline
+
+import (
+ "errors"
+ "fmt"
+ "io"
+)
+
+// ReadOptions controls decoding behavior.
+type ReadOptions struct {+ // ChompLF removes one trailing '\n' from PacketData payloads.
+ ChompLF bool
+}
+
+// Decoder reads pkt-line frames from an io.Reader.
+//
+// It is advisable to supply a buffered reader.
+//
+// It preserves frame boundaries and supports one-frame lookahead via PeekFrame.
+type Decoder struct {+ r io.Reader
+ maxData int
+ opts ReadOptions
+
+ peeked bool
+ peek Frame
+ peekErr error
+}
+
+// NewDecoder creates a decoder over r.
+func NewDecoder(r io.Reader, opts ReadOptions) *Decoder {+ return &Decoder{+ r: r,
+ maxData: LargePacketDataMax,
+ opts: opts,
+ }
+}
+
+// SetMaxData sets maximum payload size accepted for one data packet.
+//
+// Non-positive n resets to LargePacketDataMax.
+func (d *Decoder) SetMaxData(n int) {+ if n <= 0 {+ d.maxData = LargePacketDataMax
+
+ return
+ }
+
+ d.maxData = n
+}
+
+func cloneFrame(f Frame) Frame {+ if f.Type != PacketData {+ return Frame{Type: f.Type}+ }
+
+ out := Frame{Type: f.Type}+ if f.Payload != nil {+ out.Payload = append([]byte(nil), f.Payload...)
+ }
+
+ return out
+}
+
+// ReadFrame reads one frame.
+//
+// 0000 is a PacketFlush
+// 0001 is a PacketDelim
+// 0002 is a PacketResponseEnd
+// 0004 is a PacketData with empty payload
+//
+// 0003 and malformed headers return *ProtocolError.
+func (d *Decoder) ReadFrame() (Frame, error) {+ if d.peeked {+ d.peeked = false
+
+ return cloneFrame(d.peek), d.peekErr
+ }
+
+ return d.readFrame()
+}
+
+// PeekFrame returns the next frame without consuming it.
+//
+// A subsequent ReadFrame returns the same frame.
+func (d *Decoder) PeekFrame() (Frame, error) {+ if !d.peeked {+ d.peek, d.peekErr = d.readFrame()
+ d.peeked = true
+ }
+
+ return cloneFrame(d.peek), d.peekErr
+}
+
+func (d *Decoder) readFrame() (Frame, error) {+ var hdr [4]byte
+
+ _, err := io.ReadFull(d.r, hdr[:])
+ if err != nil {+ if errors.Is(err, io.EOF) {+ return Frame{}, io.EOF+ }
+
+ if errors.Is(err, io.ErrUnexpectedEOF) {+ return Frame{}, io.ErrUnexpectedEOF+ }
+
+ return Frame{}, err+ }
+
+ n, err := ParseLengthHeader(hdr)
+ if err != nil {+ return Frame{}, &ProtocolError{Header: hdr, Reason: err.Error()}+ }
+
+ switch n {+ case 0:
+ return Frame{Type: PacketFlush}, nil+ case 1:
+ return Frame{Type: PacketDelim}, nil+ case 2:
+ return Frame{Type: PacketResponseEnd}, nil+ case 3:
+ return Frame{}, &ProtocolError{Header: hdr, Reason: "invalid pkt-line length 3"}+ }
+
+ if n < 4 {+ return Frame{}, &ProtocolError{Header: hdr, Reason: fmt.Sprintf("invalid pkt-line length %d", n)}+ }
+
+ if n > LargePacketMax {+ perr := &ProtocolError{Header: hdr, Reason: fmt.Sprintf("pkt-line length %d exceeds max %d", n, LargePacketMax)}+
+ err := d.discardPayload(n - 4)
+ if err != nil {+ return Frame{}, errors.Join(perr, err)+ }
+
+ return Frame{}, perr+ }
+
+ payloadLen := n - 4
+ if payloadLen > d.maxData {+ serr := fmt.Errorf("%w: %d > %d", ErrTooLarge, payloadLen, d.maxData)+
+ err := d.discardPayload(payloadLen)
+ if err != nil {+ return Frame{}, errors.Join(serr, err)+ }
+
+ return Frame{}, serr+ }
+
+ payload := make([]byte, payloadLen)
+
+ _, err = io.ReadFull(d.r, payload)
+ if err != nil {+ if errors.Is(err, io.EOF) || errors.Is(err, io.ErrUnexpectedEOF) {+ return Frame{}, io.ErrUnexpectedEOF+ }
+
+ return Frame{}, err+ }
+
+ if d.opts.ChompLF && len(payload) > 0 && payload[len(payload)-1] == '\n' {+ payload = payload[:len(payload)-1]
+ }
+
+ return Frame{Type: PacketData, Payload: payload}, nil+}
+
+func (d *Decoder) discardPayload(n int) error {+ if n <= 0 {+ return nil
+ }
+
+ _, err := io.CopyN(io.Discard, d.r, int64(n))
+ if err == nil {+ return nil
+ }
+
+ if errors.Is(err, io.EOF) || errors.Is(err, io.ErrUnexpectedEOF) {+ return io.ErrUnexpectedEOF
+ }
+
+ return err
+}
--- /dev/null
+++ b/protocol/pktline/decoder_data_control_and_0004_test.go
@@ -1,0 +1,60 @@
+package pktline_test
+
+import (
+ "strings"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+)
+
+func TestDecoderDataControlAnd0004(t *testing.T) {+ t.Parallel()
+
+ input := "0006a\n0004000100020000"
+ dec := pktline.NewDecoder(strings.NewReader(input), pktline.ReadOptions{ChompLF: true})+
+ f, err := dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame #1: %v", err)+ }
+
+ if f.Type != pktline.PacketData || string(f.Payload) != "a" {+ t.Fatalf("frame #1 = %#v", f)+ }
+
+ f, err = dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame #2: %v", err)+ }
+
+ if f.Type != pktline.PacketData || len(f.Payload) != 0 {+ t.Fatalf("frame #2 = %#v, want empty data", f)+ }
+
+ f, err = dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame #3: %v", err)+ }
+
+ if f.Type != pktline.PacketDelim {+ t.Fatalf("frame #3 type = %v, want PacketDelim", f.Type)+ }
+
+ f, err = dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame #4: %v", err)+ }
+
+ if f.Type != pktline.PacketResponseEnd {+ t.Fatalf("frame #4 type = %v, want PacketResponseEnd", f.Type)+ }
+
+ f, err = dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame #5: %v", err)+ }
+
+ if f.Type != pktline.PacketFlush {+ t.Fatalf("frame #5 type = %v, want PacketFlush", f.Type)+ }
+}
--- /dev/null
+++ b/protocol/pktline/decoder_invalid_0003_test.go
@@ -1,0 +1,20 @@
+package pktline_test
+
+import (
+ "errors"
+ "strings"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+)
+
+func TestDecoderInvalid0003(t *testing.T) {+ t.Parallel()
+
+ dec := pktline.NewDecoder(strings.NewReader("0003"), pktline.ReadOptions{})+ _, err := dec.ReadFrame()
+
+ if _, ok := errors.AsType[*pktline.ProtocolError](err); !ok {+ t.Fatalf("got err %v, want ProtocolError", err)+ }
+}
--- /dev/null
+++ b/protocol/pktline/decoder_peek_test.go
@@ -1,0 +1,32 @@
+package pktline_test
+
+import (
+ "strings"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+)
+
+func TestDecoderPeek(t *testing.T) {+ t.Parallel()
+
+ dec := pktline.NewDecoder(strings.NewReader("0005x0000"), pktline.ReadOptions{})+
+ f, err := dec.PeekFrame()
+ if err != nil {+ t.Fatalf("PeekFrame: %v", err)+ }
+
+ if f.Type != pktline.PacketData || string(f.Payload) != "x" {+ t.Fatalf("peek frame = %#v", f)+ }
+
+ f, err = dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame: %v", err)+ }
+
+ if f.Type != pktline.PacketData || string(f.Payload) != "x" {+ t.Fatalf("read frame = %#v", f)+ }
+}
--- /dev/null
+++ b/protocol/pktline/decoder_rejects_over_maximum_length_test.go
@@ -1,0 +1,22 @@
+package pktline_test
+
+import (
+ "errors"
+ "strings"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+)
+
+func TestDecoderRejectsOverMaximumLength(t *testing.T) {+ t.Parallel()
+
+ dec := pktline.NewDecoder(strings.NewReader("fffe"), pktline.ReadOptions{})+ dec.SetMaxData(70000)
+
+ _, err := dec.ReadFrame()
+
+ if _, ok := errors.AsType[*pktline.ProtocolError](err); !ok {+ t.Fatalf("got err %v, want ProtocolError", err)+ }
+}
--- /dev/null
+++ b/protocol/pktline/decoder_resync_after_over_max_data_test.go
@@ -1,0 +1,51 @@
+package pktline_test
+
+import (
+ "bufio"
+ "bytes"
+ "errors"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+)
+
+func TestDecoderResyncAfterOverMaxData(t *testing.T) {+ t.Parallel()
+
+ var b bytes.Buffer
+
+ bw := bufio.NewWriter(&b)
+ enc := pktline.NewEncoder(bw)
+
+ err := enc.WriteData([]byte("abcd"))+ if err != nil {+ t.Fatalf("WriteData #1: %v", err)+ }
+
+ err = enc.WriteData([]byte("z"))+ if err != nil {+ t.Fatalf("WriteData #2: %v", err)+ }
+
+ err = enc.FlushIO()
+ if err != nil {+ t.Fatalf("FlushIO: %v", err)+ }
+
+ dec := pktline.NewDecoder(bytes.NewReader(b.Bytes()), pktline.ReadOptions{})+ dec.SetMaxData(1)
+
+ _, err = dec.ReadFrame()
+ if !errors.Is(err, pktline.ErrTooLarge) {+ t.Fatalf("got err %v, want ErrTooLarge", err)+ }
+
+ f, err := dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame #2: %v", err)+ }
+
+ if f.Type != pktline.PacketData || string(f.Payload) != "z" {+ t.Fatalf("got frame %#v, want data z", f)+ }
+}
--- /dev/null
+++ b/protocol/pktline/decoder_resync_after_over_wire_max_test.go
@@ -1,0 +1,37 @@
+package pktline_test
+
+import (
+ "bytes"
+ "errors"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+)
+
+func TestDecoderResyncAfterOverWireMax(t *testing.T) {+ t.Parallel()
+
+ var b bytes.Buffer
+
+ _, _ = b.WriteString("ffff")+ _, _ = b.Write(bytes.Repeat([]byte{'a'}, 65531))+ _, _ = b.WriteString("0005z")+
+ dec := pktline.NewDecoder(bytes.NewReader(b.Bytes()), pktline.ReadOptions{})+ dec.SetMaxData(70000)
+
+ _, err := dec.ReadFrame()
+
+ if _, ok := errors.AsType[*pktline.ProtocolError](err); !ok {+ t.Fatalf("got err %v, want ProtocolError", err)+ }
+
+ f, err := dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame #2: %v", err)+ }
+
+ if f.Type != pktline.PacketData || string(f.Payload) != "z" {+ t.Fatalf("got frame %#v, want data z", f)+ }
+}
--- /dev/null
+++ b/protocol/pktline/decoder_unexpected_eof_test.go
@@ -1,0 +1,21 @@
+package pktline_test
+
+import (
+ "errors"
+ "io"
+ "strings"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+)
+
+func TestDecoderUnexpectedEOF(t *testing.T) {+ t.Parallel()
+
+ dec := pktline.NewDecoder(strings.NewReader("0006a"), pktline.ReadOptions{})+
+ _, err := dec.ReadFrame()
+ if !errors.Is(err, io.ErrUnexpectedEOF) {+ t.Fatalf("got err %v, want io.ErrUnexpectedEOF", err)+ }
+}
--- /dev/null
+++ b/protocol/pktline/doc.go
@@ -1,0 +1,2 @@
+// Package pktline implements the pkt-line format specified in gitprotocol-common(5).
+package pktline
--- /dev/null
+++ b/protocol/pktline/encode_length_header_test.go
@@ -1,0 +1,28 @@
+package pktline_test
+
+import (
+ "errors"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+)
+
+func TestEncodeLengthHeader(t *testing.T) {+ t.Parallel()
+
+ var hdr [4]byte
+
+ err := pktline.EncodeLengthHeader(&hdr, 4)
+ if err != nil {+ t.Fatalf("unexpected error: %v", err)+ }
+
+ if got := string(hdr[:]); got != "0004" {+ t.Fatalf("got %q, want %q", got, "0004")+ }
+
+ err = pktline.EncodeLengthHeader(&hdr, pktline.LargePacketMax+1)
+ if !errors.Is(err, pktline.ErrInvalidLength) {+ t.Fatalf("got err %v, want ErrInvalidLength", err)+ }
+}
--- /dev/null
+++ b/protocol/pktline/encoder.go
@@ -1,0 +1,145 @@
+package pktline
+
+import (
+ "fmt"
+ "io"
+)
+
+// WriteFlusher is the output transport contract required by Encoder.
+//
+// Write emits framed bytes and Flush pushes buffered transport state.
+type WriteFlusher interface {+ io.Writer
+ Flush() error
+}
+
+// Encoder writes pkt-line frames to a flush-capable output transport.
+//
+// It writes exactly one frame per method call and does not auto-chunk data.
+type Encoder struct {+ w WriteFlusher
+ maxData int
+}
+
+// NewEncoder creates an encoder over w.
+func NewEncoder(w WriteFlusher) *Encoder {+ return &Encoder{+ w: w,
+ maxData: LargePacketDataMax,
+ }
+}
+
+// SetMaxData sets the maximum payload size accepted by WriteData.
+//
+// Non-positive n resets to LargePacketDataMax.
+func (e *Encoder) SetMaxData(n int) {+ if n <= 0 {+ e.maxData = LargePacketDataMax
+
+ return
+ }
+
+ e.maxData = n
+}
+
+func writeAll(w io.Writer, b []byte) error {+ for len(b) > 0 {+ n, err := w.Write(b)
+ if err != nil {+ return err
+ }
+
+ if n <= 0 {+ return io.ErrShortWrite
+ }
+
+ b = b[n:]
+ }
+
+ return nil
+}
+
+// WriteData writes one data frame.
+//
+// Empty payload is encoded as 0004.
+func (e *Encoder) WriteData(p []byte) error {+ maxData := e.effectiveMaxData()
+ if len(p) > maxData {+ return fmt.Errorf("%w: %d > %d", ErrTooLarge, len(p), maxData)+ }
+
+ var hdr [4]byte
+
+ err := EncodeLengthHeader(&hdr, len(p)+4)
+ if err != nil {+ return err
+ }
+
+ err = writeAll(e.w, hdr[:])
+ if err != nil {+ return err
+ }
+
+ return writeAll(e.w, p)
+}
+
+// WriteString writes one data frame containing s and returns len(s) on success.
+func (e *Encoder) WriteString(s string) (int, error) {+ err := e.WriteData([]byte(s))
+ if err != nil {+ return 0, err
+ }
+
+ return len(s), nil
+}
+
+// WriteFlush writes control frame 0000 (flush-pkt).
+func (e *Encoder) WriteFlush() error {+ return e.writeControl(0)
+}
+
+// WriteDelim writes control frame 0001 (delim-pkt).
+func (e *Encoder) WriteDelim() error {+ return e.writeControl(1)
+}
+
+// WriteResponseEnd writes control frame 0002 (response-end-pkt).
+func (e *Encoder) WriteResponseEnd() error {+ return e.writeControl(2)
+}
+
+// FlushIO flushes buffered output in the underlying transport.
+//
+// FlushIO does not emit any pkt-line control frame.
+func (e *Encoder) FlushIO() error {+ return e.w.Flush()
+}
+
+// WriteFlushAndFlushIO writes a flush-pkt (0000) then flushes transport I/O.
+func (e *Encoder) WriteFlushAndFlushIO() error {+ err := e.WriteFlush()
+ if err != nil {+ return err
+ }
+
+ return e.FlushIO()
+}
+
+func (e *Encoder) writeControl(n int) error {+ var hdr [4]byte
+
+ err := EncodeLengthHeader(&hdr, n)
+ if err != nil {+ return err
+ }
+
+ return writeAll(e.w, hdr[:])
+}
+
+func (e *Encoder) effectiveMaxData() int {+ if e.maxData <= 0 || e.maxData > LargePacketDataMax {+ return LargePacketDataMax
+ }
+
+ return e.maxData
+}
--- /dev/null
+++ b/protocol/pktline/encoder_buffered_flush_and_f_flush_test.go
@@ -1,0 +1,50 @@
+package pktline_test
+
+import (
+ "bufio"
+ "bytes"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+)
+
+func TestEncoderBufferedFlushAndFFlush(t *testing.T) {+ t.Parallel()
+
+ var out bytes.Buffer
+
+ bw := bufio.NewWriter(&out)
+ enc := pktline.NewEncoder(bw)
+
+ err := enc.WriteData([]byte("x"))+ if err != nil {+ t.Fatalf("WriteData: %v", err)+ }
+
+ if out.Len() != 0 {+ t.Fatalf("unexpected immediate output: %q", out.String())+ }
+
+ err = enc.FlushIO()
+ if err != nil {+ t.Fatalf("FlushIO: %v", err)+ }
+
+ if out.String() != "0005x" {+ t.Fatalf("got %q, want %q", out.String(), "0005x")+ }
+
+ out.Reset()
+ bw = bufio.NewWriter(&out)
+
+ enc = pktline.NewEncoder(bw)
+
+ err = enc.WriteFlushAndFlushIO()
+ if err != nil {+ t.Fatalf("WriteFlushAndFlushIO: %v", err)+ }
+
+ if out.String() != "0000" {+ t.Fatalf("got %q, want %q", out.String(), "0000")+ }
+}
--- /dev/null
+++ b/protocol/pktline/encoder_buffered_flush_behavior_test.go
@@ -1,0 +1,86 @@
+package pktline_test
+
+import (
+ "bufio"
+ "bytes"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+)
+
+func TestEncoderBufferedFlushBehavior(t *testing.T) {+ t.Parallel()
+
+ var out bytes.Buffer
+
+ bw := bufio.NewWriter(&out)
+ enc := pktline.NewEncoder(bw)
+
+ err := enc.WriteData([]byte("hello"))+ if err != nil {+ t.Fatalf("WriteData: %v", err)+ }
+
+ err = enc.WriteFlush()
+ if err != nil {+ t.Fatalf("WriteFlush: %v", err)+ }
+
+ if out.Len() != 0 {+ t.Fatalf("WriteFlush should not flush I/O, got %q", out.String())+ }
+
+ err = enc.FlushIO()
+ if err != nil {+ t.Fatalf("FlushIO: %v", err)+ }
+
+ if got, want := out.String(), "0009hello0000"; got != want {+ t.Fatalf("got %q, want %q", got, want)+ }
+
+ out.Reset()
+ bw = bufio.NewWriter(&out)
+ enc = pktline.NewEncoder(bw)
+
+ err = enc.WriteData([]byte("ok"))+ if err != nil {+ t.Fatalf("WriteData: %v", err)+ }
+
+ err = enc.WriteFlush()
+ if err != nil {+ t.Fatalf("WriteFlush: %v", err)+ }
+
+ if out.Len() != 0 {+ t.Fatalf("WriteFlush should not flush I/O, got %q", out.String())+ }
+
+ err = enc.FlushIO()
+ if err != nil {+ t.Fatalf("FlushIO: %v", err)+ }
+
+ if got, want := out.String(), "0006ok0000"; got != want {+ t.Fatalf("got %q, want %q", got, want)+ }
+
+ out.Reset()
+ bw = bufio.NewWriter(&out)
+ enc = pktline.NewEncoder(bw)
+
+ err = enc.WriteData([]byte("yo"))+ if err != nil {+ t.Fatalf("WriteData: %v", err)+ }
+
+ err = enc.WriteFlushAndFlushIO()
+ if err != nil {+ t.Fatalf("WriteFlushAndFlushIO: %v", err)+ }
+
+ if got, want := out.String(), "0006yo0000"; got != want {+ t.Fatalf("got %q, want %q", got, want)+ }
+}
--- /dev/null
+++ b/protocol/pktline/encoder_set_max_data_cannot_exceed_wire_limit_test.go
@@ -1,0 +1,26 @@
+package pktline_test
+
+import (
+ "bufio"
+ "bytes"
+ "errors"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+)
+
+func TestEncoderSetMaxDataCannotExceedWireLimit(t *testing.T) {+ t.Parallel()
+
+ var out bytes.Buffer
+
+ bw := bufio.NewWriter(&out)
+
+ enc := pktline.NewEncoder(bw)
+ enc.SetMaxData(pktline.LargePacketDataMax + 100)
+
+ err := enc.WriteData(bytes.Repeat([]byte{'x'}, pktline.LargePacketDataMax+1))+ if !errors.Is(err, pktline.ErrTooLarge) {+ t.Fatalf("got err %v, want ErrTooLarge", err)+ }
+}
--- /dev/null
+++ b/protocol/pktline/encoder_writes_frames_test.go
@@ -1,0 +1,51 @@
+package pktline_test
+
+import (
+ "bufio"
+ "bytes"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+)
+
+func TestEncoderWritesFrames(t *testing.T) {+ t.Parallel()
+
+ var b bytes.Buffer
+
+ bw := bufio.NewWriter(&b)
+
+ enc := pktline.NewEncoder(bw)
+
+ err := enc.WriteData([]byte("hi"))+ if err != nil {+ t.Fatalf("WriteData: %v", err)+ }
+
+ err = enc.WriteFlush()
+ if err != nil {+ t.Fatalf("WriteFlush: %v", err)+ }
+
+ err = enc.WriteDelim()
+ if err != nil {+ t.Fatalf("WriteDelim: %v", err)+ }
+
+ err = enc.WriteResponseEnd()
+ if err != nil {+ t.Fatalf("WriteResponseEnd: %v", err)+ }
+
+ err = enc.FlushIO()
+ if err != nil {+ t.Fatalf("FlushIO: %v", err)+ }
+
+ got := b.String()
+
+ want := "0006hi000000010002"
+ if got != want {+ t.Fatalf("got %q, want %q", got, want)+ }
+}
--- /dev/null
+++ b/protocol/pktline/errors.go
@@ -1,0 +1,31 @@
+package pktline
+
+import "errors"
+
+var (
+ // ErrInvalidLength indicates a malformed 4-byte hexadecimal length header.
+ ErrInvalidLength = errors.New("pktline: invalid length header")+ // ErrTooLarge indicates a payload exceeds configured packet data limits.
+ ErrTooLarge = errors.New("pktline: payload too large")+)
+
+// ProtocolError reports invalid pkt-line framing.
+//
+// It is returned for protocol violations such as invalid control values
+// (for example 0003) or non-hex length headers.
+type ProtocolError struct {+ Header [4]byte
+ Reason string
+}
+
+func (e *ProtocolError) Error() string {+ if e == nil {+ return "<nil>"
+ }
+
+ if e.Reason == "" {+ return "pktline: protocol error"
+ }
+
+ return "pktline: protocol error: " + e.Reason
+}
--- /dev/null
+++ b/protocol/pktline/frame.go
@@ -1,0 +1,10 @@
+package pktline
+
+// Frame is one decoded pkt-line frame.
+//
+// For PacketData, Payload holds frame bytes (possibly empty for 0004).
+// For control frames, Payload is nil.
+type Frame struct {+ Type PacketType
+ Payload []byte
+}
--- /dev/null
+++ b/protocol/pktline/header.go
@@ -1,0 +1,57 @@
+package pktline
+
+import "fmt"
+
+func hexval(b byte) int {+ switch {+ case b >= '0' && b <= '9':
+ return int(b - '0')
+ case b >= 'a' && b <= 'f':
+ return int(b-'a') + 10
+ case b >= 'A' && b <= 'F':
+ return int(b-'A') + 10
+ default:
+ return -1
+ }
+}
+
+// ParseLengthHeader parses a 4-byte hexadecimal pkt-line length header.
+//
+// The returned value is the full on-wire packet size, including the 4-byte
+// header. Semantic interpretation (data/control/error) is done by Decoder.
+//
+// The 4-byte header is only an actual length when above or equal to 4.
+// Otherwise, it indicates some control packet.
+func ParseLengthHeader(h [4]byte) (int, error) {+ a := hexval(h[0])
+ b := hexval(h[1])
+ c := hexval(h[2])
+ d := hexval(h[3])
+
+ if a < 0 || b < 0 || c < 0 || d < 0 {+ return 0, fmt.Errorf("%w: %q", ErrInvalidLength, string(h[:]))+ }
+
+ return (a << 12) | (b << 8) | (c << 4) | d, nil
+}
+
+// EncodeLengthHeader encodes n as a 4-byte hexadecimal pkt-line header.
+//
+// n is the full on-wire packet size including the 4-byte header.
+//
+// The 4-byte header is only an actual length when above or equal to 4.
+// Otherwise, it indicates some control packet.
+func EncodeLengthHeader(dst *[4]byte, n int) error {+ if n < 0 || n > LargePacketMax {+ return fmt.Errorf("%w: %d", ErrInvalidLength, n)+ }
+
+ const hex = "0123456789abcdef"
+
+ dst[0] = hex[(n>>12)&0xf]
+ dst[1] = hex[(n>>8)&0xf]
+ dst[2] = hex[(n>>4)&0xf]
+ dst[3] = hex[n&0xf]
+
+ return nil
+}
--- /dev/null
+++ b/protocol/pktline/parse_length_header_test.go
@@ -1,0 +1,26 @@
+package pktline_test
+
+import (
+ "errors"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+)
+
+func TestParseLengthHeader(t *testing.T) {+ t.Parallel()
+
+ n, err := pktline.ParseLengthHeader([4]byte{'0', '0', '0', '4'})+ if err != nil {+ t.Fatalf("unexpected error: %v", err)+ }
+
+ if n != 4 {+ t.Fatalf("got %d, want 4", n)+ }
+
+ _, err = pktline.ParseLengthHeader([4]byte{'0', '0', '0', 'x'})+ if !errors.Is(err, pktline.ErrInvalidLength) {+ t.Fatalf("got err %v, want ErrInvalidLength", err)+ }
+}
--- /dev/null
+++ b/protocol/pktline/type.go
@@ -1,0 +1,15 @@
+package pktline
+
+// PacketType identifies the kind of pkt-line frame.
+type PacketType uint8
+
+const (
+ // PacketData is a regular data frame whose payload is application-defined.
+ PacketData PacketType = iota
+ // PacketFlush is control frame 0000 and marks end of a message.
+ PacketFlush
+ // PacketDelim is control frame 0001 and separates sections in protocol v2.
+ PacketDelim
+ // PacketResponseEnd is control frame 0002 and marks response end on stateless v2 transports.
+ PacketResponseEnd
+)
--- /dev/null
+++ b/protocol/sideband64k/append.go
@@ -1,0 +1,40 @@
+package sideband64k
+
+import (
+ "fmt"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+)
+
+// AppendBand appends one side-band-64k data frame to dst.
+func AppendBand(dst []byte, band Band, payload []byte) ([]byte, error) {+ if !validBand(band) {+ return dst, fmt.Errorf("%w: %d", ErrInvalidBand, band)+ }
+
+ maxData := effectiveMaxData(DataMax)
+ if len(payload) > maxData {+ return dst, fmt.Errorf("%w: %d > %d", ErrTooLarge, len(payload), maxData)+ }
+
+ framed := make([]byte, len(payload)+1)
+ framed[0] = byte(band)
+ copy(framed[1:], payload)
+
+ return pktline.AppendData(dst, framed)
+}
+
+// AppendData appends one band-1 data frame to dst.
+func AppendData(dst, payload []byte) ([]byte, error) {+ return AppendBand(dst, BandData, payload)
+}
+
+// AppendProgress appends one band-2 progress frame to dst.
+func AppendProgress(dst, payload []byte) ([]byte, error) {+ return AppendBand(dst, BandProgress, payload)
+}
+
+// AppendError appends one band-3 error frame to dst.
+func AppendError(dst, payload []byte) ([]byte, error) {+ return AppendBand(dst, BandError, payload)
+}
--- /dev/null
+++ b/protocol/sideband64k/append_helpers_test.go
@@ -1,0 +1,30 @@
+package sideband64k_test
+
+import (
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/sideband64k"
+)
+
+func TestAppendHelpers(t *testing.T) {+ t.Parallel()
+
+ out, err := sideband64k.AppendData(nil, []byte("a"))+ if err != nil {+ t.Fatalf("AppendData: %v", err)+ }
+
+ out, err = sideband64k.AppendProgress(out, []byte("b"))+ if err != nil {+ t.Fatalf("AppendProgress: %v", err)+ }
+
+ out, err = sideband64k.AppendError(out, []byte("c"))+ if err != nil {+ t.Fatalf("AppendError: %v", err)+ }
+
+ if got, want := string(out), "0006\x01a0006\x02b0006\x03c"; got != want {+ t.Fatalf("got %q, want %q", got, want)+ }
+}
--- /dev/null
+++ b/protocol/sideband64k/append_preserves_dst_on_error_test.go
@@ -1,0 +1,34 @@
+package sideband64k_test
+
+import (
+ "bytes"
+ "errors"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/sideband64k"
+)
+
+func TestAppendBandPreservesDstOnError(t *testing.T) {+ t.Parallel()
+
+ orig := []byte("seed")+ dst := append([]byte(nil), orig...)
+
+ out, err := sideband64k.AppendBand(dst, 4, []byte("x"))+ if !errors.Is(err, sideband64k.ErrInvalidBand) {+ t.Fatalf("got err %v, want ErrInvalidBand", err)+ }
+
+ if !bytes.Equal(out, orig) {+ t.Fatalf("got %q, want %q", string(out), string(orig))+ }
+
+ out, err = sideband64k.AppendData(dst, bytes.Repeat([]byte{'x'}, sideband64k.DataMax+1))+ if !errors.Is(err, sideband64k.ErrTooLarge) {+ t.Fatalf("got err %v, want ErrTooLarge", err)+ }
+
+ if !bytes.Equal(out, orig) {+ t.Fatalf("got %q, want %q", string(out), string(orig))+ }
+}
--- /dev/null
+++ b/protocol/sideband64k/band.go
@@ -1,0 +1,13 @@
+package sideband64k
+
+// Band identifies the sideband stream within a pkt-line data frame.
+type Band uint8
+
+const (
+ // BandData carries primary payload bytes.
+ BandData Band = 1
+ // BandProgress carries progress or informational messages.
+ BandProgress Band = 2
+ // BandError carries fatal error messages.
+ BandError Band = 3
+)
--- /dev/null
+++ b/protocol/sideband64k/chunk_writer.go
@@ -1,0 +1,64 @@
+package sideband64k
+
+import "io"
+
+// ChunkWriter packetizes arbitrary stream bytes into side-band-64k data frames
+// for one fixed band.
+//
+// It never writes control packets automatically.
+type ChunkWriter struct {+ enc *Encoder
+ band Band
+}
+
+// NewChunkWriter creates a chunking adapter over enc for one band.
+func NewChunkWriter(enc *Encoder, band Band) *ChunkWriter {+ return &ChunkWriter{enc: enc, band: band}+}
+
+// Write splits p into sideband frames not larger than enc's maxData.
+func (cw *ChunkWriter) Write(p []byte) (int, error) {+ total := 0
+ maxData := cw.enc.effectiveMaxData()
+
+ for len(p) > 0 {+ n := min(len(p), maxData)
+
+ err := cw.enc.WriteBand(cw.band, p[:n])
+ if err != nil {+ return total, err
+ }
+
+ total += n
+ p = p[n:]
+ }
+
+ return total, nil
+}
+
+// ReadFrom reads from r and writes sideband frames to the encoder.
+func (cw *ChunkWriter) ReadFrom(r io.Reader) (int64, error) {+ buf := make([]byte, cw.enc.effectiveMaxData())
+
+ var total int64
+
+ for {+ n, err := r.Read(buf)
+ if n > 0 {+ werr := cw.enc.WriteBand(cw.band, buf[:n])
+ if werr != nil {+ return total, werr
+ }
+
+ total += int64(n)
+ }
+
+ if err != nil {+ if err == io.EOF {+ return total, nil
+ }
+
+ return total, err
+ }
+ }
+}
--- /dev/null
+++ b/protocol/sideband64k/chunk_writer_write_and_read_from_test.go
@@ -1,0 +1,60 @@
+package sideband64k_test
+
+import (
+ "bufio"
+ "bytes"
+ "strings"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/sideband64k"
+)
+
+func TestChunkWriterWriteAndReadFrom(t *testing.T) {+ t.Parallel()
+
+ var out bytes.Buffer
+
+ bw := bufio.NewWriter(&out)
+ enc := sideband64k.NewEncoder(bw)
+ enc.SetMaxData(3)
+
+ cw := sideband64k.NewChunkWriter(enc, sideband64k.BandProgress)
+
+ n, err := cw.Write([]byte("abcdefg"))+ if err != nil {+ t.Fatalf("Write: %v", err)+ }
+
+ if n != 7 {+ t.Fatalf("Write n=%d, want 7", n)+ }
+
+ err = enc.FlushIO()
+ if err != nil {+ t.Fatalf("FlushIO: %v", err)+ }
+
+ if got, want := out.String(), "0008\x02abc0008\x02def0006\x02g"; got != want {+ t.Fatalf("got %q, want %q", got, want)+ }
+
+ out.Reset()
+
+ rn, err := cw.ReadFrom(strings.NewReader("wxyz"))+ if err != nil {+ t.Fatalf("ReadFrom: %v", err)+ }
+
+ if rn != 4 {+ t.Fatalf("ReadFrom n=%d, want 4", rn)+ }
+
+ err = enc.FlushIO()
+ if err != nil {+ t.Fatalf("FlushIO: %v", err)+ }
+
+ if got, want := out.String(), "0008\x02wxy0006\x02z"; got != want {+ t.Fatalf("got %q, want %q", got, want)+ }
+}
--- /dev/null
+++ b/protocol/sideband64k/constants.go
@@ -1,0 +1,10 @@
+package sideband64k
+
+import "codeberg.org/lindenii/furgit/protocol/pktline"
+
+const (
+ // PacketMax is the maximum on-wire pkt-line size used by side-band-64k.
+ PacketMax = pktline.LargePacketMax
+ // DataMax is the maximum sideband payload size excluding the 1-byte band designator.
+ DataMax = pktline.LargePacketDataMax - 1
+)
--- /dev/null
+++ b/protocol/sideband64k/decoder.go
@@ -1,0 +1,158 @@
+package sideband64k
+
+import (
+ "fmt"
+ "io"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+)
+
+// ReadOptions controls sideband decoding behavior.
+type ReadOptions struct {+ // ChompLF removes one trailing '\n' from FrameData payloads only.
+ ChompLF bool
+}
+
+// Decoder reads side-band-64k frames from an io.Reader.
+//
+// It preserves frame boundaries and supports one-frame lookahead via
+// PeekFrame.
+type Decoder struct {+ dec *pktline.Decoder
+ maxData int
+ opts ReadOptions
+
+ peeked bool
+ peek Frame
+ peekErr error
+}
+
+// NewDecoder creates a decoder over r.
+func NewDecoder(r io.Reader, opts ReadOptions) *Decoder {+ d := &Decoder{+ dec: pktline.NewDecoder(r, pktline.ReadOptions{}),+ maxData: DataMax,
+ opts: opts,
+ }
+ d.dec.SetMaxData(pktline.LargePacketDataMax)
+
+ return d
+}
+
+// SetMaxData sets maximum payload size accepted for one sideband data packet.
+//
+// Non-positive n resets to DataMax.
+func (d *Decoder) SetMaxData(n int) {+ if n <= 0 {+ d.maxData = DataMax
+
+ return
+ }
+
+ d.maxData = n
+}
+
+// ReadFrame reads one frame.
+func (d *Decoder) ReadFrame() (Frame, error) {+ if d.peeked {+ d.peeked = false
+
+ return cloneFrame(d.peek), d.peekErr
+ }
+
+ return d.readFrame()
+}
+
+// PeekFrame returns the next frame without consuming it.
+func (d *Decoder) PeekFrame() (Frame, error) {+ if !d.peeked {+ d.peek, d.peekErr = d.readFrame()
+ d.peeked = true
+ }
+
+ return cloneFrame(d.peek), d.peekErr
+}
+
+func (d *Decoder) readFrame() (Frame, error) {+ f, err := d.dec.ReadFrame()
+ if err != nil {+ return Frame{}, err+ }
+
+ switch f.Type {+ case pktline.PacketFlush:
+ return Frame{Type: FrameFlush}, nil+ case pktline.PacketDelim:
+ return Frame{Type: FrameDelim}, nil+ case pktline.PacketResponseEnd:
+ return Frame{Type: FrameResponseEnd}, nil+ case pktline.PacketData:
+ if len(f.Payload) == 0 {+ return Frame{}, &ProtocolError{Reason: "missing sideband designator"}+ }
+
+ payload := f.Payload[1:]
+ if len(payload) > d.effectiveMaxData() {+ return Frame{}, fmt.Errorf("%w: %d > %d", ErrTooLarge, len(payload), d.effectiveMaxData())+ }
+
+ band := Band(f.Payload[0])
+ if !validBand(band) {+ return Frame{}, &ProtocolError{Reason: fmt.Sprintf("%v: %d", ErrInvalidBand, band)}+ }
+
+ payload = append([]byte(nil), payload...)
+ if d.opts.ChompLF && band == BandData && len(payload) > 0 && payload[len(payload)-1] == '\n' {+ payload = payload[:len(payload)-1]
+ }
+
+ return Frame{+ Type: frameTypeForBand(band),
+ Payload: payload,
+ }, nil
+ default:
+ return Frame{}, &ProtocolError{Reason: "unknown pkt-line frame type"}+ }
+}
+
+func (d *Decoder) effectiveMaxData() int {+ return effectiveMaxData(d.maxData)
+}
+
+func cloneFrame(f Frame) Frame {+ if f.Type == FrameFlush || f.Type == FrameDelim || f.Type == FrameResponseEnd {+ return Frame{Type: f.Type}+ }
+
+ out := Frame{Type: f.Type}+ if f.Payload != nil {+ out.Payload = append([]byte(nil), f.Payload...)
+ }
+
+ return out
+}
+
+func validBand(band Band) bool {+ return band == BandData || band == BandProgress || band == BandError
+}
+
+func frameTypeForBand(band Band) FrameType {+ switch band {+ case BandData:
+ return FrameData
+ case BandProgress:
+ return FrameProgress
+ case BandError:
+ return FrameError
+ default:
+ panic("invalid sideband64k band")+ }
+}
+
+func effectiveMaxData(n int) int {+ if n <= 0 || n > DataMax {+ return DataMax
+ }
+
+ return n
+}
--- /dev/null
+++ b/protocol/sideband64k/decoder_data_control_and_keepalive_test.go
@@ -1,0 +1,78 @@
+package sideband64k_test
+
+import (
+ "strings"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/sideband64k"
+)
+
+func TestDecoderDataControlAndKeepalive(t *testing.T) {+ t.Parallel()
+
+ input := "0007\x01a\n0005\x010007\x02p\n0007\x03e\n000100020000"
+ dec := sideband64k.NewDecoder(strings.NewReader(input), sideband64k.ReadOptions{ChompLF: true})+
+ f, err := dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame #1: %v", err)+ }
+
+ if f.Type != sideband64k.FrameData || string(f.Payload) != "a" {+ t.Fatalf("frame #1 = %#v", f)+ }
+
+ f, err = dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame #2: %v", err)+ }
+
+ if f.Type != sideband64k.FrameData || len(f.Payload) != 0 {+ t.Fatalf("frame #2 = %#v, want empty data", f)+ }
+
+ f, err = dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame #3: %v", err)+ }
+
+ if f.Type != sideband64k.FrameProgress || string(f.Payload) != "p\n" {+ t.Fatalf("frame #3 = %#v", f)+ }
+
+ f, err = dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame #4: %v", err)+ }
+
+ if f.Type != sideband64k.FrameError || string(f.Payload) != "e\n" {+ t.Fatalf("frame #4 = %#v", f)+ }
+
+ f, err = dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame #5: %v", err)+ }
+
+ if f.Type != sideband64k.FrameDelim {+ t.Fatalf("frame #5 type = %v, want FrameDelim", f.Type)+ }
+
+ f, err = dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame #6: %v", err)+ }
+
+ if f.Type != sideband64k.FrameResponseEnd {+ t.Fatalf("frame #6 type = %v, want FrameResponseEnd", f.Type)+ }
+
+ f, err = dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame #7: %v", err)+ }
+
+ if f.Type != sideband64k.FrameFlush {+ t.Fatalf("frame #7 type = %v, want FrameFlush", f.Type)+ }
+}
--- /dev/null
+++ b/protocol/sideband64k/decoder_invalid_band_test.go
@@ -1,0 +1,20 @@
+package sideband64k_test
+
+import (
+ "errors"
+ "strings"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/sideband64k"
+)
+
+func TestDecoderInvalidBand(t *testing.T) {+ t.Parallel()
+
+ dec := sideband64k.NewDecoder(strings.NewReader("0005\x04"), sideband64k.ReadOptions{})+ _, err := dec.ReadFrame()
+
+ if _, ok := errors.AsType[*sideband64k.ProtocolError](err); !ok {+ t.Fatalf("got err %v, want ProtocolError", err)+ }
+}
--- /dev/null
+++ b/protocol/sideband64k/decoder_invalid_empty_payload_test.go
@@ -1,0 +1,20 @@
+package sideband64k_test
+
+import (
+ "errors"
+ "strings"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/sideband64k"
+)
+
+func TestDecoderInvalidEmptyPayload(t *testing.T) {+ t.Parallel()
+
+ dec := sideband64k.NewDecoder(strings.NewReader("0004"), sideband64k.ReadOptions{})+ _, err := dec.ReadFrame()
+
+ if _, ok := errors.AsType[*sideband64k.ProtocolError](err); !ok {+ t.Fatalf("got err %v, want ProtocolError", err)+ }
+}
--- /dev/null
+++ b/protocol/sideband64k/decoder_malformed_pktline_test.go
@@ -1,0 +1,32 @@
+package sideband64k_test
+
+import (
+ "errors"
+ "strings"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+ "codeberg.org/lindenii/furgit/protocol/sideband64k"
+)
+
+func TestDecoderInvalid0003(t *testing.T) {+ t.Parallel()
+
+ dec := sideband64k.NewDecoder(strings.NewReader("0003"), sideband64k.ReadOptions{})+ _, err := dec.ReadFrame()
+
+ if _, ok := errors.AsType[*pktline.ProtocolError](err); !ok {+ t.Fatalf("got err %v, want pktline.ProtocolError", err)+ }
+}
+
+func TestDecoderRejectsOverMaximumLength(t *testing.T) {+ t.Parallel()
+
+ dec := sideband64k.NewDecoder(strings.NewReader("fffe"), sideband64k.ReadOptions{})+ _, err := dec.ReadFrame()
+
+ if _, ok := errors.AsType[*pktline.ProtocolError](err); !ok {+ t.Fatalf("got err %v, want pktline.ProtocolError", err)+ }
+}
--- /dev/null
+++ b/protocol/sideband64k/decoder_partial_read_test.go
@@ -1,0 +1,32 @@
+package sideband64k_test
+
+import (
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/sideband64k"
+)
+
+func TestDecoderHandlesPartialReads(t *testing.T) {+ t.Parallel()
+
+ r := &byteReader{data: []byte("0007\x02ok0000")}+ dec := sideband64k.NewDecoder(r, sideband64k.ReadOptions{})+
+ f, err := dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame #1: %v", err)+ }
+
+ if f.Type != sideband64k.FrameProgress || string(f.Payload) != "ok" {+ t.Fatalf("frame #1 = %#v", f)+ }
+
+ f, err = dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame #2: %v", err)+ }
+
+ if f.Type != sideband64k.FrameFlush {+ t.Fatalf("frame #2 = %#v", f)+ }
+}
--- /dev/null
+++ b/protocol/sideband64k/decoder_peek_test.go
@@ -1,0 +1,34 @@
+package sideband64k_test
+
+import (
+ "strings"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/sideband64k"
+)
+
+func TestDecoderPeek(t *testing.T) {+ t.Parallel()
+
+ dec := sideband64k.NewDecoder(strings.NewReader("0006\x01x0000"), sideband64k.ReadOptions{})+
+ f, err := dec.PeekFrame()
+ if err != nil {+ t.Fatalf("PeekFrame: %v", err)+ }
+
+ if f.Type != sideband64k.FrameData || string(f.Payload) != "x" {+ t.Fatalf("peek frame = %#v", f)+ }
+
+ f.Payload[0] = 'y'
+
+ f, err = dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame: %v", err)+ }
+
+ if f.Type != sideband64k.FrameData || string(f.Payload) != "x" {+ t.Fatalf("read frame = %#v", f)+ }
+}
--- /dev/null
+++ b/protocol/sideband64k/decoder_resync_after_over_max_data_test.go
@@ -1,0 +1,51 @@
+package sideband64k_test
+
+import (
+ "bufio"
+ "bytes"
+ "errors"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/sideband64k"
+)
+
+func TestDecoderResyncAfterOverMaxData(t *testing.T) {+ t.Parallel()
+
+ var b bytes.Buffer
+
+ bw := bufio.NewWriter(&b)
+ enc := sideband64k.NewEncoder(bw)
+
+ err := enc.WriteData([]byte("abcd"))+ if err != nil {+ t.Fatalf("WriteData #1: %v", err)+ }
+
+ err = enc.WriteData([]byte("z"))+ if err != nil {+ t.Fatalf("WriteData #2: %v", err)+ }
+
+ err = enc.FlushIO()
+ if err != nil {+ t.Fatalf("FlushIO: %v", err)+ }
+
+ dec := sideband64k.NewDecoder(bytes.NewReader(b.Bytes()), sideband64k.ReadOptions{})+ dec.SetMaxData(1)
+
+ _, err = dec.ReadFrame()
+ if !errors.Is(err, sideband64k.ErrTooLarge) {+ t.Fatalf("got err %v, want ErrTooLarge", err)+ }
+
+ f, err := dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame #2: %v", err)+ }
+
+ if f.Type != sideband64k.FrameData || string(f.Payload) != "z" {+ t.Fatalf("got frame %#v, want data z", f)+ }
+}
--- /dev/null
+++ b/protocol/sideband64k/decoder_resync_after_over_wire_max_test.go
@@ -1,0 +1,37 @@
+package sideband64k_test
+
+import (
+ "bytes"
+ "errors"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+ "codeberg.org/lindenii/furgit/protocol/sideband64k"
+)
+
+func TestDecoderResyncAfterOverWireMax(t *testing.T) {+ t.Parallel()
+
+ var b bytes.Buffer
+
+ _, _ = b.WriteString("ffff")+ _, _ = b.Write(bytes.Repeat([]byte{'a'}, 65531))+ _, _ = b.WriteString("0006\x01z")+
+ dec := sideband64k.NewDecoder(bytes.NewReader(b.Bytes()), sideband64k.ReadOptions{})+
+ _, err := dec.ReadFrame()
+
+ if _, ok := errors.AsType[*pktline.ProtocolError](err); !ok {+ t.Fatalf("got err %v, want pktline.ProtocolError", err)+ }
+
+ f, err := dec.ReadFrame()
+ if err != nil {+ t.Fatalf("ReadFrame #2: %v", err)+ }
+
+ if f.Type != sideband64k.FrameData || string(f.Payload) != "z" {+ t.Fatalf("got frame %#v, want data z", f)+ }
+}
--- /dev/null
+++ b/protocol/sideband64k/decoder_unexpected_eof_test.go
@@ -1,0 +1,21 @@
+package sideband64k_test
+
+import (
+ "errors"
+ "io"
+ "strings"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/sideband64k"
+)
+
+func TestDecoderUnexpectedEOF(t *testing.T) {+ t.Parallel()
+
+ dec := sideband64k.NewDecoder(strings.NewReader("0006\x01"), sideband64k.ReadOptions{})+
+ _, err := dec.ReadFrame()
+ if !errors.Is(err, io.ErrUnexpectedEOF) {+ t.Fatalf("got err %v, want io.ErrUnexpectedEOF", err)+ }
+}
--- /dev/null
+++ b/protocol/sideband64k/doc.go
@@ -1,0 +1,2 @@
+// Package sideband64k implements Git side-band-64k multiplexing over pkt-line.
+package sideband64k
--- /dev/null
+++ b/protocol/sideband64k/encoder.go
@@ -1,0 +1,98 @@
+package sideband64k
+
+import (
+ "fmt"
+
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+)
+
+// Encoder writes side-band-64k frames to a flush-capable output transport.
+//
+// It writes exactly one frame per method call and does not auto-chunk data.
+type Encoder struct {+ enc *pktline.Encoder
+ maxData int
+}
+
+// NewEncoder creates an encoder over w.
+func NewEncoder(w pktline.WriteFlusher) *Encoder {+ return &Encoder{+ enc: pktline.NewEncoder(w),
+ maxData: DataMax,
+ }
+}
+
+// SetMaxData sets the maximum payload size accepted by WriteBand.
+//
+// Non-positive n resets to DataMax.
+func (e *Encoder) SetMaxData(n int) {+ if n <= 0 {+ e.maxData = DataMax
+
+ return
+ }
+
+ e.maxData = n
+}
+
+// WriteBand writes one side-band-64k data frame for the given band.
+func (e *Encoder) WriteBand(band Band, p []byte) error {+ if !validBand(band) {+ return fmt.Errorf("%w: %d", ErrInvalidBand, band)+ }
+
+ maxData := e.effectiveMaxData()
+ if len(p) > maxData {+ return fmt.Errorf("%w: %d > %d", ErrTooLarge, len(p), maxData)+ }
+
+ framed := make([]byte, len(p)+1)
+ framed[0] = byte(band)
+ copy(framed[1:], p)
+
+ return e.enc.WriteData(framed)
+}
+
+// WriteData writes one band-1 data frame.
+func (e *Encoder) WriteData(p []byte) error {+ return e.WriteBand(BandData, p)
+}
+
+// WriteProgress writes one band-2 progress frame.
+func (e *Encoder) WriteProgress(p []byte) error {+ return e.WriteBand(BandProgress, p)
+}
+
+// WriteError writes one band-3 error frame.
+func (e *Encoder) WriteError(p []byte) error {+ return e.WriteBand(BandError, p)
+}
+
+// WriteFlush writes control frame 0000 (flush-pkt).
+func (e *Encoder) WriteFlush() error {+ return e.enc.WriteFlush()
+}
+
+// WriteDelim writes control frame 0001 (delim-pkt).
+func (e *Encoder) WriteDelim() error {+ return e.enc.WriteDelim()
+}
+
+// WriteResponseEnd writes control frame 0002 (response-end-pkt).
+func (e *Encoder) WriteResponseEnd() error {+ return e.enc.WriteResponseEnd()
+}
+
+// FlushIO flushes buffered output in the underlying transport.
+func (e *Encoder) FlushIO() error {+ return e.enc.FlushIO()
+}
+
+// WriteFlushAndFlushIO writes a flush-pkt (0000) then flushes transport I/O.
+func (e *Encoder) WriteFlushAndFlushIO() error {+ return e.enc.WriteFlushAndFlushIO()
+}
+
+func (e *Encoder) effectiveMaxData() int {+ return effectiveMaxData(e.maxData)
+}
--- /dev/null
+++ b/protocol/sideband64k/encoder_buffered_flush_behavior_test.go
@@ -1,0 +1,59 @@
+package sideband64k_test
+
+import (
+ "bufio"
+ "bytes"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/sideband64k"
+)
+
+func TestEncoderBufferedFlushBehavior(t *testing.T) {+ t.Parallel()
+
+ var out bytes.Buffer
+
+ bw := bufio.NewWriter(&out)
+ enc := sideband64k.NewEncoder(bw)
+
+ err := enc.WriteData([]byte("hello"))+ if err != nil {+ t.Fatalf("WriteData: %v", err)+ }
+
+ err = enc.WriteFlush()
+ if err != nil {+ t.Fatalf("WriteFlush: %v", err)+ }
+
+ if out.Len() != 0 {+ t.Fatalf("WriteFlush should not flush I/O, got %q", out.String())+ }
+
+ err = enc.FlushIO()
+ if err != nil {+ t.Fatalf("FlushIO: %v", err)+ }
+
+ if got, want := out.String(), "000a\x01hello0000"; got != want {+ t.Fatalf("got %q, want %q", got, want)+ }
+
+ out.Reset()
+ bw = bufio.NewWriter(&out)
+ enc = sideband64k.NewEncoder(bw)
+
+ err = enc.WriteData([]byte("yo"))+ if err != nil {+ t.Fatalf("WriteData: %v", err)+ }
+
+ err = enc.WriteFlushAndFlushIO()
+ if err != nil {+ t.Fatalf("WriteFlushAndFlushIO: %v", err)+ }
+
+ if got, want := out.String(), "0007\x01yo0000"; got != want {+ t.Fatalf("got %q, want %q", got, want)+ }
+}
--- /dev/null
+++ b/protocol/sideband64k/encoder_partial_write_test.go
@@ -1,0 +1,46 @@
+package sideband64k_test
+
+import (
+ "errors"
+ "io"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/sideband64k"
+)
+
+func TestEncoderHandlesPartialWrites(t *testing.T) {+ t.Parallel()
+
+ dst := &limitWriter{maxPerWrite: 2}+ enc := sideband64k.NewEncoder(dst)
+
+ err := enc.WriteProgress([]byte("abc"))+ if err != nil {+ t.Fatalf("WriteProgress: %v", err)+ }
+
+ err = enc.WriteFlushAndFlushIO()
+ if err != nil {+ t.Fatalf("WriteFlushAndFlushIO: %v", err)+ }
+
+ if got, want := dst.buf.String(), "0008\x02abc0000"; got != want {+ t.Fatalf("got %q, want %q", got, want)+ }
+
+ if dst.flushes != 1 {+ t.Fatalf("flushes=%d, want 1", dst.flushes)+ }
+}
+
+func TestEncoderReturnsShortWrite(t *testing.T) {+ t.Parallel()
+
+ dst := &limitWriter{shortWrite: true}+ enc := sideband64k.NewEncoder(dst)
+
+ err := enc.WriteData([]byte("x"))+ if !errors.Is(err, io.ErrShortWrite) {+ t.Fatalf("got err %v, want io.ErrShortWrite", err)+ }
+}
--- /dev/null
+++ b/protocol/sideband64k/encoder_set_max_data_cannot_exceed_wire_limit_test.go
@@ -1,0 +1,23 @@
+package sideband64k_test
+
+import (
+ "bytes"
+ "errors"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/sideband64k"
+)
+
+func TestEncoderSetMaxDataCannotExceedWireLimit(t *testing.T) {+ t.Parallel()
+
+ var dst limitWriter
+
+ enc := sideband64k.NewEncoder(&dst)
+ enc.SetMaxData(sideband64k.DataMax + 100)
+
+ err := enc.WriteData(bytes.Repeat([]byte{'x'}, sideband64k.DataMax+1))+ if !errors.Is(err, sideband64k.ErrTooLarge) {+ t.Fatalf("got err %v, want ErrTooLarge", err)+ }
+}
--- /dev/null
+++ b/protocol/sideband64k/encoder_writes_frames_test.go
@@ -1,0 +1,58 @@
+package sideband64k_test
+
+import (
+ "bufio"
+ "bytes"
+ "testing"
+
+ "codeberg.org/lindenii/furgit/protocol/sideband64k"
+)
+
+func TestEncoderWritesFrames(t *testing.T) {+ t.Parallel()
+
+ var b bytes.Buffer
+
+ bw := bufio.NewWriter(&b)
+ enc := sideband64k.NewEncoder(bw)
+
+ err := enc.WriteData([]byte("hi"))+ if err != nil {+ t.Fatalf("WriteData: %v", err)+ }
+
+ err = enc.WriteProgress([]byte("ok"))+ if err != nil {+ t.Fatalf("WriteProgress: %v", err)+ }
+
+ err = enc.WriteError([]byte("no"))+ if err != nil {+ t.Fatalf("WriteError: %v", err)+ }
+
+ err = enc.WriteFlush()
+ if err != nil {+ t.Fatalf("WriteFlush: %v", err)+ }
+
+ err = enc.WriteDelim()
+ if err != nil {+ t.Fatalf("WriteDelim: %v", err)+ }
+
+ err = enc.WriteResponseEnd()
+ if err != nil {+ t.Fatalf("WriteResponseEnd: %v", err)+ }
+
+ err = enc.FlushIO()
+ if err != nil {+ t.Fatalf("FlushIO: %v", err)+ }
+
+ want := "0007\x01hi0007\x02ok0007\x03no000000010002"
+ if got := b.String(); got != want {+ t.Fatalf("got %q, want %q", got, want)+ }
+}
--- /dev/null
+++ b/protocol/sideband64k/errors.go
@@ -1,0 +1,27 @@
+package sideband64k
+
+import "errors"
+
+var (
+ // ErrTooLarge indicates a payload exceeds configured sideband data limits.
+ ErrTooLarge = errors.New("sideband64k: payload too large")+ // ErrInvalidBand indicates a data frame has an invalid sideband designator.
+ ErrInvalidBand = errors.New("sideband64k: invalid band designator")+)
+
+// ProtocolError reports invalid side-band-64k framing.
+type ProtocolError struct {+ Reason string
+}
+
+func (e *ProtocolError) Error() string {+ if e == nil {+ return "<nil>"
+ }
+
+ if e.Reason == "" {+ return "sideband64k: protocol error"
+ }
+
+ return "sideband64k: protocol error: " + e.Reason
+}
--- /dev/null
+++ b/protocol/sideband64k/frame.go
@@ -1,0 +1,12 @@
+package sideband64k
+
+// Frame is one decoded side-band-64k frame.
+//
+// For FrameData, FrameProgress, and FrameError, Payload holds frame bytes and
+// may be empty.
+//
+// For control frames, Payload is nil.
+type Frame struct {+ Type FrameType
+ Payload []byte
+}
--- /dev/null
+++ b/protocol/sideband64k/frame_type.go
@@ -1,0 +1,19 @@
+package sideband64k
+
+// FrameType identifies the kind of decoded sideband frame.
+type FrameType uint8
+
+const (
+ // FrameData carries primary payload bytes from band 1.
+ FrameData FrameType = iota
+ // FrameProgress carries progress bytes from band 2.
+ FrameProgress
+ // FrameError carries fatal error bytes from band 3.
+ FrameError
+ // FrameFlush is pkt-line control frame 0000.
+ FrameFlush
+ // FrameDelim is pkt-line control frame 0001.
+ FrameDelim
+ // FrameResponseEnd is pkt-line control frame 0002.
+ FrameResponseEnd
+)
--- /dev/null
+++ b/protocol/sideband64k/helpers_test.go
@@ -1,0 +1,46 @@
+package sideband64k_test
+
+import (
+ "bytes"
+ "io"
+)
+
+type limitWriter struct {+ buf bytes.Buffer
+ maxPerWrite int
+ flushes int
+ shortWrite bool
+}
+
+func (w *limitWriter) Write(p []byte) (int, error) {+ if w.shortWrite {+ return 0, nil
+ }
+
+ if w.maxPerWrite > 0 && len(p) > w.maxPerWrite {+ p = p[:w.maxPerWrite]
+ }
+
+ return w.buf.Write(p)
+}
+
+func (w *limitWriter) Flush() error {+ w.flushes++
+
+ return nil
+}
+
+type byteReader struct {+ data []byte
+}
+
+func (r *byteReader) Read(p []byte) (int, error) {+ if len(r.data) == 0 {+ return 0, io.EOF
+ }
+
+ p[0] = r.data[0]
+ r.data = r.data[1:]
+
+ return 1, nil
+}
--- a/protocol/v0v1/server/frame.go
+++ b/protocol/v0v1/server/frame.go
@@ -1,6 +1,6 @@
package server
-import "codeberg.org/lindenii/furgit/format/pktline"
+import "codeberg.org/lindenii/furgit/protocol/pktline"
// FrameType identifies one low-level v0/v1 server pkt-line frame type.
type FrameType = pktline.PacketType
--- a/protocol/v0v1/server/receivepack/parse_test.go
+++ b/protocol/v0v1/server/receivepack/parse_test.go
@@ -5,7 +5,7 @@
"strings"
"testing"
- "codeberg.org/lindenii/furgit/format/pktline"
+ "codeberg.org/lindenii/furgit/protocol/pktline"
"codeberg.org/lindenii/furgit/internal/testgit"
"codeberg.org/lindenii/furgit/objectid"
common "codeberg.org/lindenii/furgit/protocol/v0v1/server"
--- a/protocol/v0v1/server/receivepack/report_status.go
+++ b/protocol/v0v1/server/receivepack/report_status.go
@@ -3,7 +3,7 @@
import (
"fmt"
- "codeberg.org/lindenii/furgit/format/pktline"
+ "codeberg.org/lindenii/furgit/protocol/pktline"
)
// WriteReportStatus writes one classic report-status response.
--- a/protocol/v0v1/server/receivepack/report_status_test.go
+++ b/protocol/v0v1/server/receivepack/report_status_test.go
@@ -6,8 +6,8 @@
"strings"
"testing"
- "codeberg.org/lindenii/furgit/format/pktline"
- "codeberg.org/lindenii/furgit/format/sideband64k"
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+ "codeberg.org/lindenii/furgit/protocol/sideband64k"
"codeberg.org/lindenii/furgit/internal/testgit"
"codeberg.org/lindenii/furgit/objectid"
common "codeberg.org/lindenii/furgit/protocol/v0v1/server"
--- a/protocol/v0v1/server/session.go
+++ b/protocol/v0v1/server/session.go
@@ -3,8 +3,8 @@
import (
"io"
- "codeberg.org/lindenii/furgit/format/pktline"
- "codeberg.org/lindenii/furgit/format/sideband64k"
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+ "codeberg.org/lindenii/furgit/protocol/sideband64k"
"codeberg.org/lindenii/furgit/objectid"
)
--- a/receivepack/int_test.go
+++ b/receivepack/int_test.go
@@ -9,8 +9,8 @@
"testing"
"time"
- "codeberg.org/lindenii/furgit/format/pktline"
- "codeberg.org/lindenii/furgit/format/sideband64k"
+ "codeberg.org/lindenii/furgit/protocol/pktline"
+ "codeberg.org/lindenii/furgit/protocol/sideband64k"
"codeberg.org/lindenii/furgit/internal/testgit"
"codeberg.org/lindenii/furgit/objectid"
receivepack "codeberg.org/lindenii/furgit/receivepack"
--- a/receivepack/receivepack.go
+++ b/receivepack/receivepack.go
@@ -4,7 +4,7 @@
"context"
"io"
- "codeberg.org/lindenii/furgit/format/pktline"
+ "codeberg.org/lindenii/furgit/protocol/pktline"
common "codeberg.org/lindenii/furgit/protocol/v0v1/server"
protoreceive "codeberg.org/lindenii/furgit/protocol/v0v1/server/receivepack"
"codeberg.org/lindenii/furgit/receivepack/service"
--
⑨