From: YenForYang <YenForYang@users.noreply.github.com>
Date: Tue, 28 Sep 2021 23:30:35 +0000 (-0500)
Subject: bencode: optimize `(*Decoder).parseStringInterface()` (#659)
X-Git-Tag: v1.32.0~16
X-Git-Url: http://www.git.stargrave.org/?a=commitdiff_plain;h=37455d3c6b8e50f8916980b099794d8f40191043;p=btrtrc.git

bencode: optimize `(*Decoder).parseStringInterface()` (#659)
---

diff --git a/bencode/decode.go b/bencode/decode.go
index 9c42578a..0054c867 100644
--- a/bencode/decode.go
+++ b/bencode/decode.go
@@ -611,28 +611,27 @@ func (d *Decoder) parseIntInterface() (ret interface{}) {
 	return
 }
 
-func (d *Decoder) parseStringInterface() interface{} {
-	start := d.Offset - 1
-
+func (d *Decoder) parseStringInterface() (s string) {
 	// read the string length first
 	d.readUntil(':')
-	length, err := strconv.ParseInt(d.buf.String(), 10, 64)
-	checkForIntParseError(err, start)
-
-	d.buf.Reset()
-	n, err := io.CopyN(&d.buf, d.r, length)
-	d.Offset += n
+	length, err := strconv.ParseInt(bytesAsString(d.buf.Bytes()), 10, 64)
 	if err != nil {
-		checkForUnexpectedEOF(err, d.Offset)
-		panic(&SyntaxError{
-			Offset: d.Offset,
-			What:   errors.New("unexpected I/O error: " + err.Error()),
-		})
+		panic(&SyntaxError{Offset: d.Offset-1, What: err})
 	}
-
-	s := d.buf.String()
 	d.buf.Reset()
-	return s
+	n, err := d.buf.ReadFrom(io.LimitReader(d.r, length))
+	d.Offset += n
+	switch err {
+	case nil:
+		s = d.buf.String()
+		d.buf.Reset()
+		return		
+	case io.EOF:
+		err = io.ErrUnexpectedEOF
+	default:
+		err = errors.New("unexpected I/O error: " + err.Error())
+	}
+	panic(&SyntaxError{Offset: d.Offset, What: err})
 }
 
 func (d *Decoder) parseDictInterface() interface{} {