TUN-5261: Collect QUIC metrics about RTT, packets and bytes transfered and log events at tracing level

vendor/github.com/francoispqt/gojay/decode_string_unicode.go

@@ -0,0 +1,98 @@
+package gojay
+
+import (
+	"unicode/utf16"
+	"unicode/utf8"
+)
+
+func (dec *Decoder) getUnicode() (rune, error) {
+	i := 0
+	r := rune(0)
+	for ; (dec.cursor < dec.length || dec.read()) && i < 4; dec.cursor++ {
+		c := dec.data[dec.cursor]
+		if c >= '0' && c <= '9' {
+			r = r*16 + rune(c-'0')
+		} else if c >= 'a' && c <= 'f' {
+			r = r*16 + rune(c-'a'+10)
+		} else if c >= 'A' && c <= 'F' {
+			r = r*16 + rune(c-'A'+10)
+		} else {
+			return 0, InvalidJSONError("Invalid unicode code point")
+		}
+		i++
+	}
+	return r, nil
+}
+
+func (dec *Decoder) appendEscapeChar(str []byte, c byte) ([]byte, error) {
+	switch c {
+	case 't':
+		str = append(str, '\t')
+	case 'n':
+		str = append(str, '\n')
+	case 'r':
+		str = append(str, '\r')
+	case 'b':
+		str = append(str, '\b')
+	case 'f':
+		str = append(str, '\f')
+	case '\\':
+		str = append(str, '\\')
+	default:
+		return nil, InvalidJSONError("Invalid JSON")
+	}
+	return str, nil
+}
+
+func (dec *Decoder) parseUnicode() ([]byte, error) {
+	// get unicode after u
+	r, err := dec.getUnicode()
+	if err != nil {
+		return nil, err
+	}
+	// no error start making new string
+	str := make([]byte, 16, 16)
+	i := 0
+	// check if code can be a surrogate utf16
+	if utf16.IsSurrogate(r) {
+		if dec.cursor >= dec.length && !dec.read() {
+			return nil, dec.raiseInvalidJSONErr(dec.cursor)
+		}
+		c := dec.data[dec.cursor]
+		if c != '\\' {
+			i += utf8.EncodeRune(str, r)
+			return str[:i], nil
+		}
+		dec.cursor++
+		if dec.cursor >= dec.length && !dec.read() {
+			return nil, dec.raiseInvalidJSONErr(dec.cursor)
+		}
+		c = dec.data[dec.cursor]
+		if c != 'u' {
+			i += utf8.EncodeRune(str, r)
+			str, err = dec.appendEscapeChar(str[:i], c)
+			if err != nil {
+				dec.err = err
+				return nil, err
+			}
+			i++
+			dec.cursor++
+			return str[:i], nil
+		}
+		dec.cursor++
+		r2, err := dec.getUnicode()
+		if err != nil {
+			return nil, err
+		}
+		combined := utf16.DecodeRune(r, r2)
+		if combined == '\uFFFD' {
+			i += utf8.EncodeRune(str, r)
+			i += utf8.EncodeRune(str, r2)
+		} else {
+			i += utf8.EncodeRune(str, combined)
+		}
+		return str[:i], nil
+	}
+	i += utf8.EncodeRune(str, r)
+	return str[:i], nil
+}