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Replace unpackTxtString with identical unpackString (#751) 

These two functions were identical (sans-variable names) before I
optimized unpackString in 5debfeec63.

This will improve the performance of it's only caller unpackTxt and is
covered by the test and benchmark added in 5debfeec63.
This commit is contained in:
Tom Thorogood 2018-09-26 17:44:19 +09:30 committed by Miek Gieben
parent 94dab88533
commit f195b71879
1 changed files with 1 additions and 34 deletions
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35
msg.go
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@ -512,7 +512,7 @@ func unpackTxt(msg []byte, off0 int) (ss []string, off int, err error) {
off = off0
var s string
for off < len(msg) && err == nil {
s, off, err = unpackTxtString(msg, off)
s, off, err = unpackString(msg, off)
if err == nil {
ss = append(ss, s)
}
@ -520,39 +520,6 @@ func unpackTxt(msg []byte, off0 int) (ss []string, off int, err error) {
return
}
func unpackTxtString(msg []byte, offset int) (string, int, error) {
if offset+1 > len(msg) {
return "", offset, &Error{err: "overflow unpacking txt"}
}
l := int(msg[offset])
if offset+l+1 > len(msg) {
return "", offset, &Error{err: "overflow unpacking txt"}
}
s := make([]byte, 0, l)
for _, b := range msg[offset+1 : offset+1+l] {
switch b {
case '"', '\\':
s = append(s, '\\', b)
default:
if b < 32 || b > 127 { // unprintable
var buf [3]byte
bufs := strconv.AppendInt(buf[:0], int64(b), 10)
s = append(s, '\\')
for i := 0; i < 3-len(bufs); i++ {
s = append(s, '0')
}
for _, r := range bufs {
s = append(s, r)
}
} else {
s = append(s, b)
}
}
}
offset += 1 + l
return string(s), offset, nil
}
// Helpers for dealing with escaped bytes
func isDigit(b byte) bool { return b >= '0' && b <= '9' }