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decode.go

@@ -2,8 +2,10 @@ package logfmt
 
 import (
 	"bufio"
+	"bytes"
 	"fmt"
 	"io"
+	"unicode/utf8"
 )
 
 // A Decoder reads and decodes logfmt records from an input stream.
@@ -70,14 +72,14 @@ func (dec *Decoder) ScanKeyval() bool {
 key:
 	const invalidKeyError = "invalid key"
 
-	start := dec.pos
+	start, multibyte := dec.pos, false
 	for p, c := range line[dec.pos:] {
 		switch {
 		case c == '=':
 			dec.pos += p
 			if dec.pos > start {
 				dec.key = line[start:dec.pos]
-				if invalidKey(dec.key) {
+				if multibyte && bytes.IndexRune(dec.key, utf8.RuneError) != -1 {
 					dec.syntaxError(invalidKeyError)
 					return false
 				}
@@ -95,18 +97,20 @@ key:
 			dec.pos += p
 			if dec.pos > start {
 				dec.key = line[start:dec.pos]
-				if invalidKey(dec.key) {
+				if multibyte && bytes.IndexRune(dec.key, utf8.RuneError) != -1 {
 					dec.syntaxError(invalidKeyError)
 					return false
 				}
 			}
 			return true
+		case c >= utf8.RuneSelf:
+			multibyte = true
 		}
 	}
 	dec.pos = len(line)
 	if dec.pos > start {
 		dec.key = line[start:dec.pos]
-		if invalidKey(dec.key) {
+		if multibyte && bytes.IndexRune(dec.key, utf8.RuneError) != -1 {
 			dec.syntaxError(invalidKeyError)
 			return false
 		}
@@ -200,9 +204,6 @@ func (dec *Decoder) Value() []byte {
 	return dec.value
 }
 
-// func (dec *Decoder) DecodeValue() ([]byte, error) {
-// }
-
 // Err returns the first non-EOF error that was encountered by the Scanner.
 func (dec *Decoder) Err() error {
 	return dec.err

decode_test.go

@@ -120,6 +120,7 @@ func TestDecoder_errors(t *testing.T) {
 		{"a=\"\\u1\"", &SyntaxError{Msg: "invalid quoted value", Line: 1, Pos: 8}},
 		{"a\ufffd=bar", &SyntaxError{Msg: "invalid key", Line: 1, Pos: 5}},
 		{"\x80=bar", &SyntaxError{Msg: "invalid key", Line: 1, Pos: 2}},
+		{"\x80", &SyntaxError{Msg: "invalid key", Line: 1, Pos: 2}},
 	}
 
 	for _, test := range tests {

encode.go

@@ -170,11 +170,11 @@ func invalidKeyRune(r rune) bool {
 }
 
 func invalidKeyString(key string) bool {
-	return len(key) == 0 || strings.IndexFunc(key, invalidKeyRune) != -1 || !utf8.ValidString(key)
+	return len(key) == 0 || strings.IndexFunc(key, invalidKeyRune) != -1
 }
 
 func invalidKey(key []byte) bool {
-	return len(key) == 0 || bytes.IndexFunc(key, invalidKeyRune) != -1 || !utf8.Valid(key)
+	return len(key) == 0 || bytes.IndexFunc(key, invalidKeyRune) != -1
 }
 
 func writeStringKey(w io.Writer, key string) error {
@@ -239,7 +239,7 @@ func writeStringValue(w io.Writer, value string, ok bool) error {
 	var err error
 	if ok && value == "null" {
 		_, err = io.WriteString(w, `"null"`)
-	} else if strings.IndexFunc(value, needsQuotedValueRune) != -1 || !utf8.ValidString(value) {
+	} else if strings.IndexFunc(value, needsQuotedValueRune) != -1 {
 		_, err = writeQuotedString(w, value)
 	} else {
 		_, err = io.WriteString(w, value)
@@ -249,7 +249,7 @@ func writeStringValue(w io.Writer, value string, ok bool) error {
 
 func writeBytesValue(w io.Writer, value []byte) error {
 	var err error
-	if bytes.IndexFunc(value, needsQuotedValueRune) >= 0 || !utf8.Valid(value) {
+	if bytes.IndexFunc(value, needsQuotedValueRune) != -1 {
 		_, err = writeQuotedBytes(w, value)
 	} else {
 		_, err = w.Write(value)

encode_test.go

@@ -53,11 +53,11 @@ func TestEncodeKeyval(t *testing.T) {
 		{key: decimalStringer{5, 9}, value: "v", want: "5.9=v"},
 		{key: (*decimalStringer)(nil), value: "v", err: logfmt.ErrNilKey},
 		{key: marshalerStringer{5, 9}, value: "v", want: "5.9=v"},
-		{key: "k", value: "\xbd", want: "k=\"\\ufffd\""},
-		{key: "k", value: "\ufffd\x00", want: "k=\"\\ufffd\\u0000\""},
-		{key: "k", value: "\ufffd", want: "k=\"\\ufffd\""},
-		{key: "k", value: []byte("\ufffd\x00"), want: "k=\"\\ufffd\\u0000\""},
-		{key: "k", value: []byte("\ufffd"), want: "k=\"\\ufffd\""},
+		{key: "k", value: "\xbd", want: `k="\ufffd"`},
+		{key: "k", value: "\ufffd\x00", want: `k="\ufffd\u0000"`},
+		{key: "k", value: "\ufffd", want: `k="\ufffd"`},
+		{key: "k", value: []byte("\ufffd\x00"), want: `k="\ufffd\u0000"`},
+		{key: "k", value: []byte("\ufffd"), want: `k="\ufffd"`},
 	}
 
 	for _, d := range data {

fuzz.go

@@ -73,7 +73,6 @@ func parse(data []byte) ([][]kv, error) {
 			kvs = append(kvs, kv{dec.Key(), dec.Value()})
 		}
 		got = append(got, kvs)
-		kvs = nil
 	}
 	return got, dec.Err()
 }