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