[VOL-4292] OpenOLT Adapter changes for gRPC migration
Change-Id: I5af2125f2c2f53ffc78c474a94314bba408f8bae
diff --git a/vendor/github.com/golang/protobuf/proto/text_decode.go b/vendor/github.com/golang/protobuf/proto/text_decode.go
new file mode 100644
index 0000000..47eb3e4
--- /dev/null
+++ b/vendor/github.com/golang/protobuf/proto/text_decode.go
@@ -0,0 +1,801 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package proto
+
+import (
+ "encoding"
+ "errors"
+ "fmt"
+ "reflect"
+ "strconv"
+ "strings"
+ "unicode/utf8"
+
+ "google.golang.org/protobuf/encoding/prototext"
+ protoV2 "google.golang.org/protobuf/proto"
+ "google.golang.org/protobuf/reflect/protoreflect"
+ "google.golang.org/protobuf/reflect/protoregistry"
+)
+
+const wrapTextUnmarshalV2 = false
+
+// ParseError is returned by UnmarshalText.
+type ParseError struct {
+ Message string
+
+ // Deprecated: Do not use.
+ Line, Offset int
+}
+
+func (e *ParseError) Error() string {
+ if wrapTextUnmarshalV2 {
+ return e.Message
+ }
+ if e.Line == 1 {
+ return fmt.Sprintf("line 1.%d: %v", e.Offset, e.Message)
+ }
+ return fmt.Sprintf("line %d: %v", e.Line, e.Message)
+}
+
+// UnmarshalText parses a proto text formatted string into m.
+func UnmarshalText(s string, m Message) error {
+ if u, ok := m.(encoding.TextUnmarshaler); ok {
+ return u.UnmarshalText([]byte(s))
+ }
+
+ m.Reset()
+ mi := MessageV2(m)
+
+ if wrapTextUnmarshalV2 {
+ err := prototext.UnmarshalOptions{
+ AllowPartial: true,
+ }.Unmarshal([]byte(s), mi)
+ if err != nil {
+ return &ParseError{Message: err.Error()}
+ }
+ return checkRequiredNotSet(mi)
+ } else {
+ if err := newTextParser(s).unmarshalMessage(mi.ProtoReflect(), ""); err != nil {
+ return err
+ }
+ return checkRequiredNotSet(mi)
+ }
+}
+
+type textParser struct {
+ s string // remaining input
+ done bool // whether the parsing is finished (success or error)
+ backed bool // whether back() was called
+ offset, line int
+ cur token
+}
+
+type token struct {
+ value string
+ err *ParseError
+ line int // line number
+ offset int // byte number from start of input, not start of line
+ unquoted string // the unquoted version of value, if it was a quoted string
+}
+
+func newTextParser(s string) *textParser {
+ p := new(textParser)
+ p.s = s
+ p.line = 1
+ p.cur.line = 1
+ return p
+}
+
+func (p *textParser) unmarshalMessage(m protoreflect.Message, terminator string) (err error) {
+ md := m.Descriptor()
+ fds := md.Fields()
+
+ // A struct is a sequence of "name: value", terminated by one of
+ // '>' or '}', or the end of the input. A name may also be
+ // "[extension]" or "[type/url]".
+ //
+ // The whole struct can also be an expanded Any message, like:
+ // [type/url] < ... struct contents ... >
+ seen := make(map[protoreflect.FieldNumber]bool)
+ for {
+ tok := p.next()
+ if tok.err != nil {
+ return tok.err
+ }
+ if tok.value == terminator {
+ break
+ }
+ if tok.value == "[" {
+ if err := p.unmarshalExtensionOrAny(m, seen); err != nil {
+ return err
+ }
+ continue
+ }
+
+ // This is a normal, non-extension field.
+ name := protoreflect.Name(tok.value)
+ fd := fds.ByName(name)
+ switch {
+ case fd == nil:
+ gd := fds.ByName(protoreflect.Name(strings.ToLower(string(name))))
+ if gd != nil && gd.Kind() == protoreflect.GroupKind && gd.Message().Name() == name {
+ fd = gd
+ }
+ case fd.Kind() == protoreflect.GroupKind && fd.Message().Name() != name:
+ fd = nil
+ case fd.IsWeak() && fd.Message().IsPlaceholder():
+ fd = nil
+ }
+ if fd == nil {
+ typeName := string(md.FullName())
+ if m, ok := m.Interface().(Message); ok {
+ t := reflect.TypeOf(m)
+ if t.Kind() == reflect.Ptr {
+ typeName = t.Elem().String()
+ }
+ }
+ return p.errorf("unknown field name %q in %v", name, typeName)
+ }
+ if od := fd.ContainingOneof(); od != nil && m.WhichOneof(od) != nil {
+ return p.errorf("field '%s' would overwrite already parsed oneof '%s'", name, od.Name())
+ }
+ if fd.Cardinality() != protoreflect.Repeated && seen[fd.Number()] {
+ return p.errorf("non-repeated field %q was repeated", fd.Name())
+ }
+ seen[fd.Number()] = true
+
+ // Consume any colon.
+ if err := p.checkForColon(fd); err != nil {
+ return err
+ }
+
+ // Parse into the field.
+ v := m.Get(fd)
+ if !m.Has(fd) && (fd.IsList() || fd.IsMap() || fd.Message() != nil) {
+ v = m.Mutable(fd)
+ }
+ if v, err = p.unmarshalValue(v, fd); err != nil {
+ return err
+ }
+ m.Set(fd, v)
+
+ if err := p.consumeOptionalSeparator(); err != nil {
+ return err
+ }
+ }
+ return nil
+}
+
+func (p *textParser) unmarshalExtensionOrAny(m protoreflect.Message, seen map[protoreflect.FieldNumber]bool) error {
+ name, err := p.consumeExtensionOrAnyName()
+ if err != nil {
+ return err
+ }
+
+ // If it contains a slash, it's an Any type URL.
+ if slashIdx := strings.LastIndex(name, "/"); slashIdx >= 0 {
+ tok := p.next()
+ if tok.err != nil {
+ return tok.err
+ }
+ // consume an optional colon
+ if tok.value == ":" {
+ tok = p.next()
+ if tok.err != nil {
+ return tok.err
+ }
+ }
+
+ var terminator string
+ switch tok.value {
+ case "<":
+ terminator = ">"
+ case "{":
+ terminator = "}"
+ default:
+ return p.errorf("expected '{' or '<', found %q", tok.value)
+ }
+
+ mt, err := protoregistry.GlobalTypes.FindMessageByURL(name)
+ if err != nil {
+ return p.errorf("unrecognized message %q in google.protobuf.Any", name[slashIdx+len("/"):])
+ }
+ m2 := mt.New()
+ if err := p.unmarshalMessage(m2, terminator); err != nil {
+ return err
+ }
+ b, err := protoV2.Marshal(m2.Interface())
+ if err != nil {
+ return p.errorf("failed to marshal message of type %q: %v", name[slashIdx+len("/"):], err)
+ }
+
+ urlFD := m.Descriptor().Fields().ByName("type_url")
+ valFD := m.Descriptor().Fields().ByName("value")
+ if seen[urlFD.Number()] {
+ return p.errorf("Any message unpacked multiple times, or %q already set", urlFD.Name())
+ }
+ if seen[valFD.Number()] {
+ return p.errorf("Any message unpacked multiple times, or %q already set", valFD.Name())
+ }
+ m.Set(urlFD, protoreflect.ValueOfString(name))
+ m.Set(valFD, protoreflect.ValueOfBytes(b))
+ seen[urlFD.Number()] = true
+ seen[valFD.Number()] = true
+ return nil
+ }
+
+ xname := protoreflect.FullName(name)
+ xt, _ := protoregistry.GlobalTypes.FindExtensionByName(xname)
+ if xt == nil && isMessageSet(m.Descriptor()) {
+ xt, _ = protoregistry.GlobalTypes.FindExtensionByName(xname.Append("message_set_extension"))
+ }
+ if xt == nil {
+ return p.errorf("unrecognized extension %q", name)
+ }
+ fd := xt.TypeDescriptor()
+ if fd.ContainingMessage().FullName() != m.Descriptor().FullName() {
+ return p.errorf("extension field %q does not extend message %q", name, m.Descriptor().FullName())
+ }
+
+ if err := p.checkForColon(fd); err != nil {
+ return err
+ }
+
+ v := m.Get(fd)
+ if !m.Has(fd) && (fd.IsList() || fd.IsMap() || fd.Message() != nil) {
+ v = m.Mutable(fd)
+ }
+ v, err = p.unmarshalValue(v, fd)
+ if err != nil {
+ return err
+ }
+ m.Set(fd, v)
+ return p.consumeOptionalSeparator()
+}
+
+func (p *textParser) unmarshalValue(v protoreflect.Value, fd protoreflect.FieldDescriptor) (protoreflect.Value, error) {
+ tok := p.next()
+ if tok.err != nil {
+ return v, tok.err
+ }
+ if tok.value == "" {
+ return v, p.errorf("unexpected EOF")
+ }
+
+ switch {
+ case fd.IsList():
+ lv := v.List()
+ var err error
+ if tok.value == "[" {
+ // Repeated field with list notation, like [1,2,3].
+ for {
+ vv := lv.NewElement()
+ vv, err = p.unmarshalSingularValue(vv, fd)
+ if err != nil {
+ return v, err
+ }
+ lv.Append(vv)
+
+ tok := p.next()
+ if tok.err != nil {
+ return v, tok.err
+ }
+ if tok.value == "]" {
+ break
+ }
+ if tok.value != "," {
+ return v, p.errorf("Expected ']' or ',' found %q", tok.value)
+ }
+ }
+ return v, nil
+ }
+
+ // One value of the repeated field.
+ p.back()
+ vv := lv.NewElement()
+ vv, err = p.unmarshalSingularValue(vv, fd)
+ if err != nil {
+ return v, err
+ }
+ lv.Append(vv)
+ return v, nil
+ case fd.IsMap():
+ // The map entry should be this sequence of tokens:
+ // < key : KEY value : VALUE >
+ // However, implementations may omit key or value, and technically
+ // we should support them in any order.
+ var terminator string
+ switch tok.value {
+ case "<":
+ terminator = ">"
+ case "{":
+ terminator = "}"
+ default:
+ return v, p.errorf("expected '{' or '<', found %q", tok.value)
+ }
+
+ keyFD := fd.MapKey()
+ valFD := fd.MapValue()
+
+ mv := v.Map()
+ kv := keyFD.Default()
+ vv := mv.NewValue()
+ for {
+ tok := p.next()
+ if tok.err != nil {
+ return v, tok.err
+ }
+ if tok.value == terminator {
+ break
+ }
+ var err error
+ switch tok.value {
+ case "key":
+ if err := p.consumeToken(":"); err != nil {
+ return v, err
+ }
+ if kv, err = p.unmarshalSingularValue(kv, keyFD); err != nil {
+ return v, err
+ }
+ if err := p.consumeOptionalSeparator(); err != nil {
+ return v, err
+ }
+ case "value":
+ if err := p.checkForColon(valFD); err != nil {
+ return v, err
+ }
+ if vv, err = p.unmarshalSingularValue(vv, valFD); err != nil {
+ return v, err
+ }
+ if err := p.consumeOptionalSeparator(); err != nil {
+ return v, err
+ }
+ default:
+ p.back()
+ return v, p.errorf(`expected "key", "value", or %q, found %q`, terminator, tok.value)
+ }
+ }
+ mv.Set(kv.MapKey(), vv)
+ return v, nil
+ default:
+ p.back()
+ return p.unmarshalSingularValue(v, fd)
+ }
+}
+
+func (p *textParser) unmarshalSingularValue(v protoreflect.Value, fd protoreflect.FieldDescriptor) (protoreflect.Value, error) {
+ tok := p.next()
+ if tok.err != nil {
+ return v, tok.err
+ }
+ if tok.value == "" {
+ return v, p.errorf("unexpected EOF")
+ }
+
+ switch fd.Kind() {
+ case protoreflect.BoolKind:
+ switch tok.value {
+ case "true", "1", "t", "True":
+ return protoreflect.ValueOfBool(true), nil
+ case "false", "0", "f", "False":
+ return protoreflect.ValueOfBool(false), nil
+ }
+ case protoreflect.Int32Kind, protoreflect.Sint32Kind, protoreflect.Sfixed32Kind:
+ if x, err := strconv.ParseInt(tok.value, 0, 32); err == nil {
+ return protoreflect.ValueOfInt32(int32(x)), nil
+ }
+
+ // The C++ parser accepts large positive hex numbers that uses
+ // two's complement arithmetic to represent negative numbers.
+ // This feature is here for backwards compatibility with C++.
+ if strings.HasPrefix(tok.value, "0x") {
+ if x, err := strconv.ParseUint(tok.value, 0, 32); err == nil {
+ return protoreflect.ValueOfInt32(int32(-(int64(^x) + 1))), nil
+ }
+ }
+ case protoreflect.Int64Kind, protoreflect.Sint64Kind, protoreflect.Sfixed64Kind:
+ if x, err := strconv.ParseInt(tok.value, 0, 64); err == nil {
+ return protoreflect.ValueOfInt64(int64(x)), nil
+ }
+
+ // The C++ parser accepts large positive hex numbers that uses
+ // two's complement arithmetic to represent negative numbers.
+ // This feature is here for backwards compatibility with C++.
+ if strings.HasPrefix(tok.value, "0x") {
+ if x, err := strconv.ParseUint(tok.value, 0, 64); err == nil {
+ return protoreflect.ValueOfInt64(int64(-(int64(^x) + 1))), nil
+ }
+ }
+ case protoreflect.Uint32Kind, protoreflect.Fixed32Kind:
+ if x, err := strconv.ParseUint(tok.value, 0, 32); err == nil {
+ return protoreflect.ValueOfUint32(uint32(x)), nil
+ }
+ case protoreflect.Uint64Kind, protoreflect.Fixed64Kind:
+ if x, err := strconv.ParseUint(tok.value, 0, 64); err == nil {
+ return protoreflect.ValueOfUint64(uint64(x)), nil
+ }
+ case protoreflect.FloatKind:
+ // Ignore 'f' for compatibility with output generated by C++,
+ // but don't remove 'f' when the value is "-inf" or "inf".
+ v := tok.value
+ if strings.HasSuffix(v, "f") && v != "-inf" && v != "inf" {
+ v = v[:len(v)-len("f")]
+ }
+ if x, err := strconv.ParseFloat(v, 32); err == nil {
+ return protoreflect.ValueOfFloat32(float32(x)), nil
+ }
+ case protoreflect.DoubleKind:
+ // Ignore 'f' for compatibility with output generated by C++,
+ // but don't remove 'f' when the value is "-inf" or "inf".
+ v := tok.value
+ if strings.HasSuffix(v, "f") && v != "-inf" && v != "inf" {
+ v = v[:len(v)-len("f")]
+ }
+ if x, err := strconv.ParseFloat(v, 64); err == nil {
+ return protoreflect.ValueOfFloat64(float64(x)), nil
+ }
+ case protoreflect.StringKind:
+ if isQuote(tok.value[0]) {
+ return protoreflect.ValueOfString(tok.unquoted), nil
+ }
+ case protoreflect.BytesKind:
+ if isQuote(tok.value[0]) {
+ return protoreflect.ValueOfBytes([]byte(tok.unquoted)), nil
+ }
+ case protoreflect.EnumKind:
+ if x, err := strconv.ParseInt(tok.value, 0, 32); err == nil {
+ return protoreflect.ValueOfEnum(protoreflect.EnumNumber(x)), nil
+ }
+ vd := fd.Enum().Values().ByName(protoreflect.Name(tok.value))
+ if vd != nil {
+ return protoreflect.ValueOfEnum(vd.Number()), nil
+ }
+ case protoreflect.MessageKind, protoreflect.GroupKind:
+ var terminator string
+ switch tok.value {
+ case "{":
+ terminator = "}"
+ case "<":
+ terminator = ">"
+ default:
+ return v, p.errorf("expected '{' or '<', found %q", tok.value)
+ }
+ err := p.unmarshalMessage(v.Message(), terminator)
+ return v, err
+ default:
+ panic(fmt.Sprintf("invalid kind %v", fd.Kind()))
+ }
+ return v, p.errorf("invalid %v: %v", fd.Kind(), tok.value)
+}
+
+// Consume a ':' from the input stream (if the next token is a colon),
+// returning an error if a colon is needed but not present.
+func (p *textParser) checkForColon(fd protoreflect.FieldDescriptor) *ParseError {
+ tok := p.next()
+ if tok.err != nil {
+ return tok.err
+ }
+ if tok.value != ":" {
+ if fd.Message() == nil {
+ return p.errorf("expected ':', found %q", tok.value)
+ }
+ p.back()
+ }
+ return nil
+}
+
+// consumeExtensionOrAnyName consumes an extension name or an Any type URL and
+// the following ']'. It returns the name or URL consumed.
+func (p *textParser) consumeExtensionOrAnyName() (string, error) {
+ tok := p.next()
+ if tok.err != nil {
+ return "", tok.err
+ }
+
+ // If extension name or type url is quoted, it's a single token.
+ if len(tok.value) > 2 && isQuote(tok.value[0]) && tok.value[len(tok.value)-1] == tok.value[0] {
+ name, err := unquoteC(tok.value[1:len(tok.value)-1], rune(tok.value[0]))
+ if err != nil {
+ return "", err
+ }
+ return name, p.consumeToken("]")
+ }
+
+ // Consume everything up to "]"
+ var parts []string
+ for tok.value != "]" {
+ parts = append(parts, tok.value)
+ tok = p.next()
+ if tok.err != nil {
+ return "", p.errorf("unrecognized type_url or extension name: %s", tok.err)
+ }
+ if p.done && tok.value != "]" {
+ return "", p.errorf("unclosed type_url or extension name")
+ }
+ }
+ return strings.Join(parts, ""), nil
+}
+
+// consumeOptionalSeparator consumes an optional semicolon or comma.
+// It is used in unmarshalMessage to provide backward compatibility.
+func (p *textParser) consumeOptionalSeparator() error {
+ tok := p.next()
+ if tok.err != nil {
+ return tok.err
+ }
+ if tok.value != ";" && tok.value != "," {
+ p.back()
+ }
+ return nil
+}
+
+func (p *textParser) errorf(format string, a ...interface{}) *ParseError {
+ pe := &ParseError{fmt.Sprintf(format, a...), p.cur.line, p.cur.offset}
+ p.cur.err = pe
+ p.done = true
+ return pe
+}
+
+func (p *textParser) skipWhitespace() {
+ i := 0
+ for i < len(p.s) && (isWhitespace(p.s[i]) || p.s[i] == '#') {
+ if p.s[i] == '#' {
+ // comment; skip to end of line or input
+ for i < len(p.s) && p.s[i] != '\n' {
+ i++
+ }
+ if i == len(p.s) {
+ break
+ }
+ }
+ if p.s[i] == '\n' {
+ p.line++
+ }
+ i++
+ }
+ p.offset += i
+ p.s = p.s[i:len(p.s)]
+ if len(p.s) == 0 {
+ p.done = true
+ }
+}
+
+func (p *textParser) advance() {
+ // Skip whitespace
+ p.skipWhitespace()
+ if p.done {
+ return
+ }
+
+ // Start of non-whitespace
+ p.cur.err = nil
+ p.cur.offset, p.cur.line = p.offset, p.line
+ p.cur.unquoted = ""
+ switch p.s[0] {
+ case '<', '>', '{', '}', ':', '[', ']', ';', ',', '/':
+ // Single symbol
+ p.cur.value, p.s = p.s[0:1], p.s[1:len(p.s)]
+ case '"', '\'':
+ // Quoted string
+ i := 1
+ for i < len(p.s) && p.s[i] != p.s[0] && p.s[i] != '\n' {
+ if p.s[i] == '\\' && i+1 < len(p.s) {
+ // skip escaped char
+ i++
+ }
+ i++
+ }
+ if i >= len(p.s) || p.s[i] != p.s[0] {
+ p.errorf("unmatched quote")
+ return
+ }
+ unq, err := unquoteC(p.s[1:i], rune(p.s[0]))
+ if err != nil {
+ p.errorf("invalid quoted string %s: %v", p.s[0:i+1], err)
+ return
+ }
+ p.cur.value, p.s = p.s[0:i+1], p.s[i+1:len(p.s)]
+ p.cur.unquoted = unq
+ default:
+ i := 0
+ for i < len(p.s) && isIdentOrNumberChar(p.s[i]) {
+ i++
+ }
+ if i == 0 {
+ p.errorf("unexpected byte %#x", p.s[0])
+ return
+ }
+ p.cur.value, p.s = p.s[0:i], p.s[i:len(p.s)]
+ }
+ p.offset += len(p.cur.value)
+}
+
+// Back off the parser by one token. Can only be done between calls to next().
+// It makes the next advance() a no-op.
+func (p *textParser) back() { p.backed = true }
+
+// Advances the parser and returns the new current token.
+func (p *textParser) next() *token {
+ if p.backed || p.done {
+ p.backed = false
+ return &p.cur
+ }
+ p.advance()
+ if p.done {
+ p.cur.value = ""
+ } else if len(p.cur.value) > 0 && isQuote(p.cur.value[0]) {
+ // Look for multiple quoted strings separated by whitespace,
+ // and concatenate them.
+ cat := p.cur
+ for {
+ p.skipWhitespace()
+ if p.done || !isQuote(p.s[0]) {
+ break
+ }
+ p.advance()
+ if p.cur.err != nil {
+ return &p.cur
+ }
+ cat.value += " " + p.cur.value
+ cat.unquoted += p.cur.unquoted
+ }
+ p.done = false // parser may have seen EOF, but we want to return cat
+ p.cur = cat
+ }
+ return &p.cur
+}
+
+func (p *textParser) consumeToken(s string) error {
+ tok := p.next()
+ if tok.err != nil {
+ return tok.err
+ }
+ if tok.value != s {
+ p.back()
+ return p.errorf("expected %q, found %q", s, tok.value)
+ }
+ return nil
+}
+
+var errBadUTF8 = errors.New("proto: bad UTF-8")
+
+func unquoteC(s string, quote rune) (string, error) {
+ // This is based on C++'s tokenizer.cc.
+ // Despite its name, this is *not* parsing C syntax.
+ // For instance, "\0" is an invalid quoted string.
+
+ // Avoid allocation in trivial cases.
+ simple := true
+ for _, r := range s {
+ if r == '\\' || r == quote {
+ simple = false
+ break
+ }
+ }
+ if simple {
+ return s, nil
+ }
+
+ buf := make([]byte, 0, 3*len(s)/2)
+ for len(s) > 0 {
+ r, n := utf8.DecodeRuneInString(s)
+ if r == utf8.RuneError && n == 1 {
+ return "", errBadUTF8
+ }
+ s = s[n:]
+ if r != '\\' {
+ if r < utf8.RuneSelf {
+ buf = append(buf, byte(r))
+ } else {
+ buf = append(buf, string(r)...)
+ }
+ continue
+ }
+
+ ch, tail, err := unescape(s)
+ if err != nil {
+ return "", err
+ }
+ buf = append(buf, ch...)
+ s = tail
+ }
+ return string(buf), nil
+}
+
+func unescape(s string) (ch string, tail string, err error) {
+ r, n := utf8.DecodeRuneInString(s)
+ if r == utf8.RuneError && n == 1 {
+ return "", "", errBadUTF8
+ }
+ s = s[n:]
+ switch r {
+ case 'a':
+ return "\a", s, nil
+ case 'b':
+ return "\b", s, nil
+ case 'f':
+ return "\f", s, nil
+ case 'n':
+ return "\n", s, nil
+ case 'r':
+ return "\r", s, nil
+ case 't':
+ return "\t", s, nil
+ case 'v':
+ return "\v", s, nil
+ case '?':
+ return "?", s, nil // trigraph workaround
+ case '\'', '"', '\\':
+ return string(r), s, nil
+ case '0', '1', '2', '3', '4', '5', '6', '7':
+ if len(s) < 2 {
+ return "", "", fmt.Errorf(`\%c requires 2 following digits`, r)
+ }
+ ss := string(r) + s[:2]
+ s = s[2:]
+ i, err := strconv.ParseUint(ss, 8, 8)
+ if err != nil {
+ return "", "", fmt.Errorf(`\%s contains non-octal digits`, ss)
+ }
+ return string([]byte{byte(i)}), s, nil
+ case 'x', 'X', 'u', 'U':
+ var n int
+ switch r {
+ case 'x', 'X':
+ n = 2
+ case 'u':
+ n = 4
+ case 'U':
+ n = 8
+ }
+ if len(s) < n {
+ return "", "", fmt.Errorf(`\%c requires %d following digits`, r, n)
+ }
+ ss := s[:n]
+ s = s[n:]
+ i, err := strconv.ParseUint(ss, 16, 64)
+ if err != nil {
+ return "", "", fmt.Errorf(`\%c%s contains non-hexadecimal digits`, r, ss)
+ }
+ if r == 'x' || r == 'X' {
+ return string([]byte{byte(i)}), s, nil
+ }
+ if i > utf8.MaxRune {
+ return "", "", fmt.Errorf(`\%c%s is not a valid Unicode code point`, r, ss)
+ }
+ return string(rune(i)), s, nil
+ }
+ return "", "", fmt.Errorf(`unknown escape \%c`, r)
+}
+
+func isIdentOrNumberChar(c byte) bool {
+ switch {
+ case 'A' <= c && c <= 'Z', 'a' <= c && c <= 'z':
+ return true
+ case '0' <= c && c <= '9':
+ return true
+ }
+ switch c {
+ case '-', '+', '.', '_':
+ return true
+ }
+ return false
+}
+
+func isWhitespace(c byte) bool {
+ switch c {
+ case ' ', '\t', '\n', '\r':
+ return true
+ }
+ return false
+}
+
+func isQuote(c byte) bool {
+ switch c {
+ case '"', '\'':
+ return true
+ }
+ return false
+}