fix: encode DEL (0x7f) control character (go-logfmt#17)

Fixes: 3f5ba89

Author: spaceone

encode.go

@@ -170,7 +170,7 @@ func writeKey(w io.Writer, key interface{}) error {
 // functions it causes them to remove invalid key runes from strings or byte
 // slices respectively.
 func keyRuneFilter(r rune) rune {
-	if r <= ' ' || r == '=' || r == '"' || r == 0x7f || r == utf8.RuneError {
+	if r <= ' ' || r == '=' || r == '"' || r == utf8.RuneError {
 		return -1
 	}
 	return r
@@ -233,7 +233,7 @@ func writeValue(w io.Writer, value interface{}) error {
 }
 
 func needsQuotedValueRune(r rune) bool {
-	return r <= ' ' || r == '=' || r == '"' || r == utf8.RuneError
+	return r <= ' ' || r == '=' || r == '"' || r == 0x7f || r == utf8.RuneError
 }
 
 func writeStringValue(w io.Writer, value string, ok bool) error {

jsonstring.go

@@ -98,7 +98,7 @@ func writeQuotedBytes(w io.Writer, s []byte) (int, error) {
 	start := 0
 	for i := 0; i < len(s); {
 		if b := s[i]; b < utf8.RuneSelf {
-			if 0x20 <= b && b != '\\' && b != '"' {
+			if 0x20 <= b && b != '\\' && b != '"' && b != 0x7f {
 				i++
 				continue
 			}