debian-mirror-gitlab/workhorse/internal/git/pktline.go
2021-02-22 17:27:13 +05:30

59 lines
1.4 KiB
Go

package git
import (
"bufio"
"bytes"
"fmt"
"io"
"strconv"
)
func scanDeepen(body io.Reader) bool {
scanner := bufio.NewScanner(body)
scanner.Split(pktLineSplitter)
for scanner.Scan() {
if bytes.HasPrefix(scanner.Bytes(), []byte("deepen")) && scanner.Err() == nil {
return true
}
}
return false
}
func pktLineSplitter(data []byte, atEOF bool) (advance int, token []byte, err error) {
if len(data) < 4 {
if atEOF && len(data) > 0 {
return 0, nil, fmt.Errorf("pktLineSplitter: incomplete length prefix on %q", data)
}
return 0, nil, nil // want more data
}
if bytes.HasPrefix(data, []byte("0000")) {
// special case: "0000" terminator packet: return empty token
return 4, data[:0], nil
}
// We have at least 4 bytes available so we can decode the 4-hex digit
// length prefix of the packet line.
pktLength64, err := strconv.ParseInt(string(data[:4]), 16, 0)
if err != nil {
return 0, nil, fmt.Errorf("pktLineSplitter: decode length: %v", err)
}
// Cast is safe because we requested an int-size number from strconv.ParseInt
pktLength := int(pktLength64)
if pktLength < 0 {
return 0, nil, fmt.Errorf("pktLineSplitter: invalid length: %d", pktLength)
}
if len(data) < pktLength {
if atEOF {
return 0, nil, fmt.Errorf("pktLineSplitter: less than %d bytes in input %q", pktLength, data)
}
return 0, nil, nil // want more data
}
// return "pkt" token without length prefix
return pktLength, data[4:pktLength], nil
}