add vendor data

vendor/github.com/dunglas/httpsfv/binary.go

@@ -0,0 +1,59 @@
+package httpsfv
+
+import (
+	"encoding/base64"
+	"errors"
+	"strings"
+)
+
+// ErrInvalidBinaryFormat is returned when the binary format is invalid.
+var ErrInvalidBinaryFormat = errors.New("invalid binary format")
+
+// marshalBinary serializes as defined in
+// https://httpwg.org/specs/rfc9651.html#ser-binary.
+func marshalBinary(b *strings.Builder, bs []byte) error {
+	if err := b.WriteByte(':'); err != nil {
+		return err
+	}
+
+	buf := make([]byte, base64.StdEncoding.EncodedLen(len(bs)))
+	base64.StdEncoding.Encode(buf, bs)
+
+	if _, err := b.Write(buf); err != nil {
+		return err
+	}
+
+	return b.WriteByte(':')
+}
+
+// parseBinary parses as defined in
+// https://httpwg.org/specs/rfc9651.html#parse-binary.
+func parseBinary(s *scanner) ([]byte, error) {
+	if s.eof() || s.data[s.off] != ':' {
+		return nil, &UnmarshalError{s.off, ErrInvalidBinaryFormat}
+	}
+	s.off++
+
+	start := s.off
+
+	for !s.eof() {
+		c := s.data[s.off]
+		if c == ':' {
+			// base64decode
+			decoded, err := base64.StdEncoding.DecodeString(s.data[start:s.off])
+			if err != nil {
+				return nil, &UnmarshalError{s.off, err}
+			}
+			s.off++
+
+			return decoded, nil
+		}
+
+		if !isAlpha(c) && !isDigit(c) && c != '+' && c != '/' && c != '=' {
+			return nil, &UnmarshalError{s.off, ErrInvalidBinaryFormat}
+		}
+		s.off++
+	}
+
+	return nil, &UnmarshalError{s.off, ErrInvalidBinaryFormat}
+}