X-Git-Url: http://www.git.cypherpunks.ru/?a=blobdiff_plain;f=r.go;h=9bb12adf92a3b09e8df9a8569ed77bc15fb192b1;hb=HEAD;hp=0637ec692af823aeaba9abf7ffe462a041b00677;hpb=fff06d86fd4a1302ca2e71acd1b79fd9d7bb56bb;p=netstring.git

diff --git a/r.go b/r.go
index 0637ec6..9bb12ad 100644
--- a/r.go
+++ b/r.go
@@ -1,26 +1,24 @@
-/*
-netstring -- netstring format serialization library
-Copyright (C) 2015-2021 Sergey Matveev <stargrave@stargrave.org>
-
-This program is free software: you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation, version 3 of the License.
-
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-GNU General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
+// netstring -- netstring format serialization library
+// Copyright (C) 2015-2024 Sergey Matveev <stargrave@stargrave.org>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, version 3 of the License.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 package netstring
 
 import (
 	"bufio"
-	"bytes"
 	"errors"
+	"fmt"
 	"io"
 	"strconv"
 )
@@ -44,33 +42,36 @@ func (r *Reader) Next() (uint64, error) {
 	if !r.eof {
 		return 0, errors.New("current chunk is unread")
 	}
-	p, _ := r.r.Peek(21)
-	if len(p) == 0 {
-		return 0, io.EOF
+	lenRaw, err := r.r.ReadSlice(':')
+	if err != nil {
+		return 0, fmt.Errorf("netstring header: %w", err)
 	}
-	idx := bytes.IndexByte(p, ':')
-	if idx == -1 {
-		return 0, errors.New("no length separator found")
+	lenRaw = lenRaw[:len(lenRaw)-1]
+	if len(lenRaw) > 1 && lenRaw[0] == '0' {
+		return 0, errors.New("netstring header: leading zero")
 	}
-	size, err := strconv.ParseUint(string(p[:idx]), 10, 64)
+	size, err := strconv.ParseUint(string(lenRaw), 10, 64)
 	if err != nil {
-		return 0, err
-	}
-	if _, err = r.r.Discard(idx + 1); err != nil {
-		return 0, err
+		return 0, fmt.Errorf("netstring header: %w", err)
 	}
 	r.left = size
 	r.eof = false
-	return size, nil
+	if r.left == 0 {
+		err = r.checkTerminator()
+		if err == nil {
+			r.eof = true
+		}
+	}
+	return size, err
 }
 
 func (r *Reader) checkTerminator() error {
 	b, err := r.r.ReadByte()
 	if err != nil {
-		return err
+		return fmt.Errorf("netstring terminator: %w", err)
 	}
 	if b != ',' {
-		return errors.New("no terminator found")
+		return errors.New("netstring terminator: not found")
 	}
 	return nil
 }