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Girish Gowdrad27a1902021-02-23 16:19:08 -08001// Go support for Protocol Buffers - Google's data interchange format
2//
3// Copyright 2010 The Go Authors. All rights reserved.
4// https://github.com/golang/protobuf
5//
6// Redistribution and use in source and binary forms, with or without
7// modification, are permitted provided that the following conditions are
8// met:
9//
10// * Redistributions of source code must retain the above copyright
11// notice, this list of conditions and the following disclaimer.
12// * Redistributions in binary form must reproduce the above
13// copyright notice, this list of conditions and the following disclaimer
14// in the documentation and/or other materials provided with the
15// distribution.
16// * Neither the name of Google Inc. nor the names of its
17// contributors may be used to endorse or promote products derived from
18// this software without specific prior written permission.
19//
20// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
23// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
24// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
25// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
26// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
30// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31
32package proto
33
34// Functions for parsing the Text protocol buffer format.
35// TODO: message sets.
36
37import (
38 "encoding"
39 "errors"
40 "fmt"
41 "reflect"
42 "strconv"
43 "strings"
44 "unicode/utf8"
45)
46
47// Error string emitted when deserializing Any and fields are already set
48const anyRepeatedlyUnpacked = "Any message unpacked multiple times, or %q already set"
49
50type ParseError struct {
51 Message string
52 Line int // 1-based line number
53 Offset int // 0-based byte offset from start of input
54}
55
56func (p *ParseError) Error() string {
57 if p.Line == 1 {
58 // show offset only for first line
59 return fmt.Sprintf("line 1.%d: %v", p.Offset, p.Message)
60 }
61 return fmt.Sprintf("line %d: %v", p.Line, p.Message)
62}
63
64type token struct {
65 value string
66 err *ParseError
67 line int // line number
68 offset int // byte number from start of input, not start of line
69 unquoted string // the unquoted version of value, if it was a quoted string
70}
71
72func (t *token) String() string {
73 if t.err == nil {
74 return fmt.Sprintf("%q (line=%d, offset=%d)", t.value, t.line, t.offset)
75 }
76 return fmt.Sprintf("parse error: %v", t.err)
77}
78
79type textParser struct {
80 s string // remaining input
81 done bool // whether the parsing is finished (success or error)
82 backed bool // whether back() was called
83 offset, line int
84 cur token
85}
86
87func newTextParser(s string) *textParser {
88 p := new(textParser)
89 p.s = s
90 p.line = 1
91 p.cur.line = 1
92 return p
93}
94
95func (p *textParser) errorf(format string, a ...interface{}) *ParseError {
96 pe := &ParseError{fmt.Sprintf(format, a...), p.cur.line, p.cur.offset}
97 p.cur.err = pe
98 p.done = true
99 return pe
100}
101
102// Numbers and identifiers are matched by [-+._A-Za-z0-9]
103func isIdentOrNumberChar(c byte) bool {
104 switch {
105 case 'A' <= c && c <= 'Z', 'a' <= c && c <= 'z':
106 return true
107 case '0' <= c && c <= '9':
108 return true
109 }
110 switch c {
111 case '-', '+', '.', '_':
112 return true
113 }
114 return false
115}
116
117func isWhitespace(c byte) bool {
118 switch c {
119 case ' ', '\t', '\n', '\r':
120 return true
121 }
122 return false
123}
124
125func isQuote(c byte) bool {
126 switch c {
127 case '"', '\'':
128 return true
129 }
130 return false
131}
132
133func (p *textParser) skipWhitespace() {
134 i := 0
135 for i < len(p.s) && (isWhitespace(p.s[i]) || p.s[i] == '#') {
136 if p.s[i] == '#' {
137 // comment; skip to end of line or input
138 for i < len(p.s) && p.s[i] != '\n' {
139 i++
140 }
141 if i == len(p.s) {
142 break
143 }
144 }
145 if p.s[i] == '\n' {
146 p.line++
147 }
148 i++
149 }
150 p.offset += i
151 p.s = p.s[i:len(p.s)]
152 if len(p.s) == 0 {
153 p.done = true
154 }
155}
156
157func (p *textParser) advance() {
158 // Skip whitespace
159 p.skipWhitespace()
160 if p.done {
161 return
162 }
163
164 // Start of non-whitespace
165 p.cur.err = nil
166 p.cur.offset, p.cur.line = p.offset, p.line
167 p.cur.unquoted = ""
168 switch p.s[0] {
169 case '<', '>', '{', '}', ':', '[', ']', ';', ',', '/':
170 // Single symbol
171 p.cur.value, p.s = p.s[0:1], p.s[1:len(p.s)]
172 case '"', '\'':
173 // Quoted string
174 i := 1
175 for i < len(p.s) && p.s[i] != p.s[0] && p.s[i] != '\n' {
176 if p.s[i] == '\\' && i+1 < len(p.s) {
177 // skip escaped char
178 i++
179 }
180 i++
181 }
182 if i >= len(p.s) || p.s[i] != p.s[0] {
183 p.errorf("unmatched quote")
184 return
185 }
186 unq, err := unquoteC(p.s[1:i], rune(p.s[0]))
187 if err != nil {
188 p.errorf("invalid quoted string %s: %v", p.s[0:i+1], err)
189 return
190 }
191 p.cur.value, p.s = p.s[0:i+1], p.s[i+1:len(p.s)]
192 p.cur.unquoted = unq
193 default:
194 i := 0
195 for i < len(p.s) && isIdentOrNumberChar(p.s[i]) {
196 i++
197 }
198 if i == 0 {
199 p.errorf("unexpected byte %#x", p.s[0])
200 return
201 }
202 p.cur.value, p.s = p.s[0:i], p.s[i:len(p.s)]
203 }
204 p.offset += len(p.cur.value)
205}
206
207var (
208 errBadUTF8 = errors.New("proto: bad UTF-8")
209)
210
211func unquoteC(s string, quote rune) (string, error) {
212 // This is based on C++'s tokenizer.cc.
213 // Despite its name, this is *not* parsing C syntax.
214 // For instance, "\0" is an invalid quoted string.
215
216 // Avoid allocation in trivial cases.
217 simple := true
218 for _, r := range s {
219 if r == '\\' || r == quote {
220 simple = false
221 break
222 }
223 }
224 if simple {
225 return s, nil
226 }
227
228 buf := make([]byte, 0, 3*len(s)/2)
229 for len(s) > 0 {
230 r, n := utf8.DecodeRuneInString(s)
231 if r == utf8.RuneError && n == 1 {
232 return "", errBadUTF8
233 }
234 s = s[n:]
235 if r != '\\' {
236 if r < utf8.RuneSelf {
237 buf = append(buf, byte(r))
238 } else {
239 buf = append(buf, string(r)...)
240 }
241 continue
242 }
243
244 ch, tail, err := unescape(s)
245 if err != nil {
246 return "", err
247 }
248 buf = append(buf, ch...)
249 s = tail
250 }
251 return string(buf), nil
252}
253
254func unescape(s string) (ch string, tail string, err error) {
255 r, n := utf8.DecodeRuneInString(s)
256 if r == utf8.RuneError && n == 1 {
257 return "", "", errBadUTF8
258 }
259 s = s[n:]
260 switch r {
261 case 'a':
262 return "\a", s, nil
263 case 'b':
264 return "\b", s, nil
265 case 'f':
266 return "\f", s, nil
267 case 'n':
268 return "\n", s, nil
269 case 'r':
270 return "\r", s, nil
271 case 't':
272 return "\t", s, nil
273 case 'v':
274 return "\v", s, nil
275 case '?':
276 return "?", s, nil // trigraph workaround
277 case '\'', '"', '\\':
278 return string(r), s, nil
279 case '0', '1', '2', '3', '4', '5', '6', '7':
280 if len(s) < 2 {
281 return "", "", fmt.Errorf(`\%c requires 2 following digits`, r)
282 }
283 ss := string(r) + s[:2]
284 s = s[2:]
285 i, err := strconv.ParseUint(ss, 8, 8)
286 if err != nil {
287 return "", "", fmt.Errorf(`\%s contains non-octal digits`, ss)
288 }
289 return string([]byte{byte(i)}), s, nil
290 case 'x', 'X', 'u', 'U':
291 var n int
292 switch r {
293 case 'x', 'X':
294 n = 2
295 case 'u':
296 n = 4
297 case 'U':
298 n = 8
299 }
300 if len(s) < n {
301 return "", "", fmt.Errorf(`\%c requires %d following digits`, r, n)
302 }
303 ss := s[:n]
304 s = s[n:]
305 i, err := strconv.ParseUint(ss, 16, 64)
306 if err != nil {
307 return "", "", fmt.Errorf(`\%c%s contains non-hexadecimal digits`, r, ss)
308 }
309 if r == 'x' || r == 'X' {
310 return string([]byte{byte(i)}), s, nil
311 }
312 if i > utf8.MaxRune {
313 return "", "", fmt.Errorf(`\%c%s is not a valid Unicode code point`, r, ss)
314 }
315 return string(i), s, nil
316 }
317 return "", "", fmt.Errorf(`unknown escape \%c`, r)
318}
319
320// Back off the parser by one token. Can only be done between calls to next().
321// It makes the next advance() a no-op.
322func (p *textParser) back() { p.backed = true }
323
324// Advances the parser and returns the new current token.
325func (p *textParser) next() *token {
326 if p.backed || p.done {
327 p.backed = false
328 return &p.cur
329 }
330 p.advance()
331 if p.done {
332 p.cur.value = ""
333 } else if len(p.cur.value) > 0 && isQuote(p.cur.value[0]) {
334 // Look for multiple quoted strings separated by whitespace,
335 // and concatenate them.
336 cat := p.cur
337 for {
338 p.skipWhitespace()
339 if p.done || !isQuote(p.s[0]) {
340 break
341 }
342 p.advance()
343 if p.cur.err != nil {
344 return &p.cur
345 }
346 cat.value += " " + p.cur.value
347 cat.unquoted += p.cur.unquoted
348 }
349 p.done = false // parser may have seen EOF, but we want to return cat
350 p.cur = cat
351 }
352 return &p.cur
353}
354
355func (p *textParser) consumeToken(s string) error {
356 tok := p.next()
357 if tok.err != nil {
358 return tok.err
359 }
360 if tok.value != s {
361 p.back()
362 return p.errorf("expected %q, found %q", s, tok.value)
363 }
364 return nil
365}
366
367// Return a RequiredNotSetError indicating which required field was not set.
368func (p *textParser) missingRequiredFieldError(sv reflect.Value) *RequiredNotSetError {
369 st := sv.Type()
370 sprops := GetProperties(st)
371 for i := 0; i < st.NumField(); i++ {
372 if !isNil(sv.Field(i)) {
373 continue
374 }
375
376 props := sprops.Prop[i]
377 if props.Required {
378 return &RequiredNotSetError{fmt.Sprintf("%v.%v", st, props.OrigName)}
379 }
380 }
381 return &RequiredNotSetError{fmt.Sprintf("%v.<unknown field name>", st)} // should not happen
382}
383
384// Returns the index in the struct for the named field, as well as the parsed tag properties.
385func structFieldByName(sprops *StructProperties, name string) (int, *Properties, bool) {
386 i, ok := sprops.decoderOrigNames[name]
387 if ok {
388 return i, sprops.Prop[i], true
389 }
390 return -1, nil, false
391}
392
393// Consume a ':' from the input stream (if the next token is a colon),
394// returning an error if a colon is needed but not present.
395func (p *textParser) checkForColon(props *Properties, typ reflect.Type) *ParseError {
396 tok := p.next()
397 if tok.err != nil {
398 return tok.err
399 }
400 if tok.value != ":" {
401 // Colon is optional when the field is a group or message.
402 needColon := true
403 switch props.Wire {
404 case "group":
405 needColon = false
406 case "bytes":
407 // A "bytes" field is either a message, a string, or a repeated field;
408 // those three become *T, *string and []T respectively, so we can check for
409 // this field being a pointer to a non-string.
410 if typ.Kind() == reflect.Ptr {
411 // *T or *string
412 if typ.Elem().Kind() == reflect.String {
413 break
414 }
415 } else if typ.Kind() == reflect.Slice {
416 // []T or []*T
417 if typ.Elem().Kind() != reflect.Ptr {
418 break
419 }
420 } else if typ.Kind() == reflect.String {
421 // The proto3 exception is for a string field,
422 // which requires a colon.
423 break
424 }
425 needColon = false
426 }
427 if needColon {
428 return p.errorf("expected ':', found %q", tok.value)
429 }
430 p.back()
431 }
432 return nil
433}
434
435func (p *textParser) readStruct(sv reflect.Value, terminator string) error {
436 st := sv.Type()
437 sprops := GetProperties(st)
438 reqCount := sprops.reqCount
439 var reqFieldErr error
440 fieldSet := make(map[string]bool)
441 // A struct is a sequence of "name: value", terminated by one of
442 // '>' or '}', or the end of the input. A name may also be
443 // "[extension]" or "[type/url]".
444 //
445 // The whole struct can also be an expanded Any message, like:
446 // [type/url] < ... struct contents ... >
447 for {
448 tok := p.next()
449 if tok.err != nil {
450 return tok.err
451 }
452 if tok.value == terminator {
453 break
454 }
455 if tok.value == "[" {
456 // Looks like an extension or an Any.
457 //
458 // TODO: Check whether we need to handle
459 // namespace rooted names (e.g. ".something.Foo").
460 extName, err := p.consumeExtName()
461 if err != nil {
462 return err
463 }
464
465 if s := strings.LastIndex(extName, "/"); s >= 0 {
466 // If it contains a slash, it's an Any type URL.
467 messageName := extName[s+1:]
468 mt := MessageType(messageName)
469 if mt == nil {
470 return p.errorf("unrecognized message %q in google.protobuf.Any", messageName)
471 }
472 tok = p.next()
473 if tok.err != nil {
474 return tok.err
475 }
476 // consume an optional colon
477 if tok.value == ":" {
478 tok = p.next()
479 if tok.err != nil {
480 return tok.err
481 }
482 }
483 var terminator string
484 switch tok.value {
485 case "<":
486 terminator = ">"
487 case "{":
488 terminator = "}"
489 default:
490 return p.errorf("expected '{' or '<', found %q", tok.value)
491 }
492 v := reflect.New(mt.Elem())
493 if pe := p.readStruct(v.Elem(), terminator); pe != nil {
494 return pe
495 }
496 b, err := Marshal(v.Interface().(Message))
497 if err != nil {
498 return p.errorf("failed to marshal message of type %q: %v", messageName, err)
499 }
500 if fieldSet["type_url"] {
501 return p.errorf(anyRepeatedlyUnpacked, "type_url")
502 }
503 if fieldSet["value"] {
504 return p.errorf(anyRepeatedlyUnpacked, "value")
505 }
506 sv.FieldByName("TypeUrl").SetString(extName)
507 sv.FieldByName("Value").SetBytes(b)
508 fieldSet["type_url"] = true
509 fieldSet["value"] = true
510 continue
511 }
512
513 var desc *ExtensionDesc
514 // This could be faster, but it's functional.
515 // TODO: Do something smarter than a linear scan.
516 for _, d := range RegisteredExtensions(reflect.New(st).Interface().(Message)) {
517 if d.Name == extName {
518 desc = d
519 break
520 }
521 }
522 if desc == nil {
523 return p.errorf("unrecognized extension %q", extName)
524 }
525
526 props := &Properties{}
527 props.Parse(desc.Tag)
528
529 typ := reflect.TypeOf(desc.ExtensionType)
530 if err := p.checkForColon(props, typ); err != nil {
531 return err
532 }
533
534 rep := desc.repeated()
535
536 // Read the extension structure, and set it in
537 // the value we're constructing.
538 var ext reflect.Value
539 if !rep {
540 ext = reflect.New(typ).Elem()
541 } else {
542 ext = reflect.New(typ.Elem()).Elem()
543 }
544 if err := p.readAny(ext, props); err != nil {
545 if _, ok := err.(*RequiredNotSetError); !ok {
546 return err
547 }
548 reqFieldErr = err
549 }
550 ep := sv.Addr().Interface().(Message)
551 if !rep {
552 SetExtension(ep, desc, ext.Interface())
553 } else {
554 old, err := GetExtension(ep, desc)
555 var sl reflect.Value
556 if err == nil {
557 sl = reflect.ValueOf(old) // existing slice
558 } else {
559 sl = reflect.MakeSlice(typ, 0, 1)
560 }
561 sl = reflect.Append(sl, ext)
562 SetExtension(ep, desc, sl.Interface())
563 }
564 if err := p.consumeOptionalSeparator(); err != nil {
565 return err
566 }
567 continue
568 }
569
570 // This is a normal, non-extension field.
571 name := tok.value
572 var dst reflect.Value
573 fi, props, ok := structFieldByName(sprops, name)
574 if ok {
575 dst = sv.Field(fi)
576 } else if oop, ok := sprops.OneofTypes[name]; ok {
577 // It is a oneof.
578 props = oop.Prop
579 nv := reflect.New(oop.Type.Elem())
580 dst = nv.Elem().Field(0)
581 field := sv.Field(oop.Field)
582 if !field.IsNil() {
583 return p.errorf("field '%s' would overwrite already parsed oneof '%s'", name, sv.Type().Field(oop.Field).Name)
584 }
585 field.Set(nv)
586 }
587 if !dst.IsValid() {
588 return p.errorf("unknown field name %q in %v", name, st)
589 }
590
591 if dst.Kind() == reflect.Map {
592 // Consume any colon.
593 if err := p.checkForColon(props, dst.Type()); err != nil {
594 return err
595 }
596
597 // Construct the map if it doesn't already exist.
598 if dst.IsNil() {
599 dst.Set(reflect.MakeMap(dst.Type()))
600 }
601 key := reflect.New(dst.Type().Key()).Elem()
602 val := reflect.New(dst.Type().Elem()).Elem()
603
604 // The map entry should be this sequence of tokens:
605 // < key : KEY value : VALUE >
606 // However, implementations may omit key or value, and technically
607 // we should support them in any order. See b/28924776 for a time
608 // this went wrong.
609
610 tok := p.next()
611 var terminator string
612 switch tok.value {
613 case "<":
614 terminator = ">"
615 case "{":
616 terminator = "}"
617 default:
618 return p.errorf("expected '{' or '<', found %q", tok.value)
619 }
620 for {
621 tok := p.next()
622 if tok.err != nil {
623 return tok.err
624 }
625 if tok.value == terminator {
626 break
627 }
628 switch tok.value {
629 case "key":
630 if err := p.consumeToken(":"); err != nil {
631 return err
632 }
633 if err := p.readAny(key, props.MapKeyProp); err != nil {
634 return err
635 }
636 if err := p.consumeOptionalSeparator(); err != nil {
637 return err
638 }
639 case "value":
640 if err := p.checkForColon(props.MapValProp, dst.Type().Elem()); err != nil {
641 return err
642 }
643 if err := p.readAny(val, props.MapValProp); err != nil {
644 return err
645 }
646 if err := p.consumeOptionalSeparator(); err != nil {
647 return err
648 }
649 default:
650 p.back()
651 return p.errorf(`expected "key", "value", or %q, found %q`, terminator, tok.value)
652 }
653 }
654
655 dst.SetMapIndex(key, val)
656 continue
657 }
658
659 // Check that it's not already set if it's not a repeated field.
660 if !props.Repeated && fieldSet[name] {
661 return p.errorf("non-repeated field %q was repeated", name)
662 }
663
664 if err := p.checkForColon(props, dst.Type()); err != nil {
665 return err
666 }
667
668 // Parse into the field.
669 fieldSet[name] = true
670 if err := p.readAny(dst, props); err != nil {
671 if _, ok := err.(*RequiredNotSetError); !ok {
672 return err
673 }
674 reqFieldErr = err
675 }
676 if props.Required {
677 reqCount--
678 }
679
680 if err := p.consumeOptionalSeparator(); err != nil {
681 return err
682 }
683
684 }
685
686 if reqCount > 0 {
687 return p.missingRequiredFieldError(sv)
688 }
689 return reqFieldErr
690}
691
692// consumeExtName consumes extension name or expanded Any type URL and the
693// following ']'. It returns the name or URL consumed.
694func (p *textParser) consumeExtName() (string, error) {
695 tok := p.next()
696 if tok.err != nil {
697 return "", tok.err
698 }
699
700 // If extension name or type url is quoted, it's a single token.
701 if len(tok.value) > 2 && isQuote(tok.value[0]) && tok.value[len(tok.value)-1] == tok.value[0] {
702 name, err := unquoteC(tok.value[1:len(tok.value)-1], rune(tok.value[0]))
703 if err != nil {
704 return "", err
705 }
706 return name, p.consumeToken("]")
707 }
708
709 // Consume everything up to "]"
710 var parts []string
711 for tok.value != "]" {
712 parts = append(parts, tok.value)
713 tok = p.next()
714 if tok.err != nil {
715 return "", p.errorf("unrecognized type_url or extension name: %s", tok.err)
716 }
717 if p.done && tok.value != "]" {
718 return "", p.errorf("unclosed type_url or extension name")
719 }
720 }
721 return strings.Join(parts, ""), nil
722}
723
724// consumeOptionalSeparator consumes an optional semicolon or comma.
725// It is used in readStruct to provide backward compatibility.
726func (p *textParser) consumeOptionalSeparator() error {
727 tok := p.next()
728 if tok.err != nil {
729 return tok.err
730 }
731 if tok.value != ";" && tok.value != "," {
732 p.back()
733 }
734 return nil
735}
736
737func (p *textParser) readAny(v reflect.Value, props *Properties) error {
738 tok := p.next()
739 if tok.err != nil {
740 return tok.err
741 }
742 if tok.value == "" {
743 return p.errorf("unexpected EOF")
744 }
745
746 switch fv := v; fv.Kind() {
747 case reflect.Slice:
748 at := v.Type()
749 if at.Elem().Kind() == reflect.Uint8 {
750 // Special case for []byte
751 if tok.value[0] != '"' && tok.value[0] != '\'' {
752 // Deliberately written out here, as the error after
753 // this switch statement would write "invalid []byte: ...",
754 // which is not as user-friendly.
755 return p.errorf("invalid string: %v", tok.value)
756 }
757 bytes := []byte(tok.unquoted)
758 fv.Set(reflect.ValueOf(bytes))
759 return nil
760 }
761 // Repeated field.
762 if tok.value == "[" {
763 // Repeated field with list notation, like [1,2,3].
764 for {
765 fv.Set(reflect.Append(fv, reflect.New(at.Elem()).Elem()))
766 err := p.readAny(fv.Index(fv.Len()-1), props)
767 if err != nil {
768 return err
769 }
770 tok := p.next()
771 if tok.err != nil {
772 return tok.err
773 }
774 if tok.value == "]" {
775 break
776 }
777 if tok.value != "," {
778 return p.errorf("Expected ']' or ',' found %q", tok.value)
779 }
780 }
781 return nil
782 }
783 // One value of the repeated field.
784 p.back()
785 fv.Set(reflect.Append(fv, reflect.New(at.Elem()).Elem()))
786 return p.readAny(fv.Index(fv.Len()-1), props)
787 case reflect.Bool:
788 // true/1/t/True or false/f/0/False.
789 switch tok.value {
790 case "true", "1", "t", "True":
791 fv.SetBool(true)
792 return nil
793 case "false", "0", "f", "False":
794 fv.SetBool(false)
795 return nil
796 }
797 case reflect.Float32, reflect.Float64:
798 v := tok.value
799 // Ignore 'f' for compatibility with output generated by C++, but don't
800 // remove 'f' when the value is "-inf" or "inf".
801 if strings.HasSuffix(v, "f") && tok.value != "-inf" && tok.value != "inf" {
802 v = v[:len(v)-1]
803 }
804 if f, err := strconv.ParseFloat(v, fv.Type().Bits()); err == nil {
805 fv.SetFloat(f)
806 return nil
807 }
808 case reflect.Int32:
809 if x, err := strconv.ParseInt(tok.value, 0, 32); err == nil {
810 fv.SetInt(x)
811 return nil
812 }
813
814 if len(props.Enum) == 0 {
815 break
816 }
817 m, ok := enumValueMaps[props.Enum]
818 if !ok {
819 break
820 }
821 x, ok := m[tok.value]
822 if !ok {
823 break
824 }
825 fv.SetInt(int64(x))
826 return nil
827 case reflect.Int64:
828 if x, err := strconv.ParseInt(tok.value, 0, 64); err == nil {
829 fv.SetInt(x)
830 return nil
831 }
832
833 case reflect.Ptr:
834 // A basic field (indirected through pointer), or a repeated message/group
835 p.back()
836 fv.Set(reflect.New(fv.Type().Elem()))
837 return p.readAny(fv.Elem(), props)
838 case reflect.String:
839 if tok.value[0] == '"' || tok.value[0] == '\'' {
840 fv.SetString(tok.unquoted)
841 return nil
842 }
843 case reflect.Struct:
844 var terminator string
845 switch tok.value {
846 case "{":
847 terminator = "}"
848 case "<":
849 terminator = ">"
850 default:
851 return p.errorf("expected '{' or '<', found %q", tok.value)
852 }
853 // TODO: Handle nested messages which implement encoding.TextUnmarshaler.
854 return p.readStruct(fv, terminator)
855 case reflect.Uint32:
856 if x, err := strconv.ParseUint(tok.value, 0, 32); err == nil {
857 fv.SetUint(uint64(x))
858 return nil
859 }
860 case reflect.Uint64:
861 if x, err := strconv.ParseUint(tok.value, 0, 64); err == nil {
862 fv.SetUint(x)
863 return nil
864 }
865 }
866 return p.errorf("invalid %v: %v", v.Type(), tok.value)
867}
868
869// UnmarshalText reads a protocol buffer in Text format. UnmarshalText resets pb
870// before starting to unmarshal, so any existing data in pb is always removed.
871// If a required field is not set and no other error occurs,
872// UnmarshalText returns *RequiredNotSetError.
873func UnmarshalText(s string, pb Message) error {
874 if um, ok := pb.(encoding.TextUnmarshaler); ok {
875 return um.UnmarshalText([]byte(s))
876 }
877 pb.Reset()
878 v := reflect.ValueOf(pb)
879 return newTextParser(s).readStruct(v.Elem(), "")
880}