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-rw-r--r--vendor/google.golang.org/protobuf/internal/encoding/text/decode.go665
1 files changed, 665 insertions, 0 deletions
diff --git a/vendor/google.golang.org/protobuf/internal/encoding/text/decode.go b/vendor/google.golang.org/protobuf/internal/encoding/text/decode.go
new file mode 100644
index 000000000..eb10ea102
--- /dev/null
+++ b/vendor/google.golang.org/protobuf/internal/encoding/text/decode.go
@@ -0,0 +1,665 @@
+// Copyright 2018 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 text
+
+import (
+ "bytes"
+ "fmt"
+ "io"
+ "regexp"
+ "strconv"
+ "unicode/utf8"
+
+ "google.golang.org/protobuf/internal/errors"
+)
+
+// Decoder is a token-based textproto decoder.
+type Decoder struct {
+ // lastCall is last method called, either readCall or peekCall.
+ // Initial value is readCall.
+ lastCall call
+
+ // lastToken contains the last read token.
+ lastToken Token
+
+ // lastErr contains the last read error.
+ lastErr error
+
+ // openStack is a stack containing the byte characters for MessageOpen and
+ // ListOpen kinds. The top of stack represents the message or the list that
+ // the current token is nested in. An empty stack means the current token is
+ // at the top level message. The characters '{' and '<' both represent the
+ // MessageOpen kind.
+ openStack []byte
+
+ // orig is used in reporting line and column.
+ orig []byte
+ // in contains the unconsumed input.
+ in []byte
+}
+
+// NewDecoder returns a Decoder to read the given []byte.
+func NewDecoder(b []byte) *Decoder {
+ return &Decoder{orig: b, in: b}
+}
+
+// ErrUnexpectedEOF means that EOF was encountered in the middle of the input.
+var ErrUnexpectedEOF = errors.New("%v", io.ErrUnexpectedEOF)
+
+// call specifies which Decoder method was invoked.
+type call uint8
+
+const (
+ readCall call = iota
+ peekCall
+)
+
+// Peek looks ahead and returns the next token and error without advancing a read.
+func (d *Decoder) Peek() (Token, error) {
+ defer func() { d.lastCall = peekCall }()
+ if d.lastCall == readCall {
+ d.lastToken, d.lastErr = d.Read()
+ }
+ return d.lastToken, d.lastErr
+}
+
+// Read returns the next token.
+// It will return an error if there is no valid token.
+func (d *Decoder) Read() (Token, error) {
+ defer func() { d.lastCall = readCall }()
+ if d.lastCall == peekCall {
+ return d.lastToken, d.lastErr
+ }
+
+ tok, err := d.parseNext(d.lastToken.kind)
+ if err != nil {
+ return Token{}, err
+ }
+
+ switch tok.kind {
+ case comma, semicolon:
+ tok, err = d.parseNext(tok.kind)
+ if err != nil {
+ return Token{}, err
+ }
+ }
+ d.lastToken = tok
+ return tok, nil
+}
+
+const (
+ mismatchedFmt = "mismatched close character %q"
+ unexpectedFmt = "unexpected character %q"
+)
+
+// parseNext parses the next Token based on given last kind.
+func (d *Decoder) parseNext(lastKind Kind) (Token, error) {
+ // Trim leading spaces.
+ d.consume(0)
+ isEOF := false
+ if len(d.in) == 0 {
+ isEOF = true
+ }
+
+ switch lastKind {
+ case EOF:
+ return d.consumeToken(EOF, 0, 0), nil
+
+ case bof:
+ // Start of top level message. Next token can be EOF or Name.
+ if isEOF {
+ return d.consumeToken(EOF, 0, 0), nil
+ }
+ return d.parseFieldName()
+
+ case Name:
+ // Next token can be MessageOpen, ListOpen or Scalar.
+ if isEOF {
+ return Token{}, ErrUnexpectedEOF
+ }
+ switch ch := d.in[0]; ch {
+ case '{', '<':
+ d.pushOpenStack(ch)
+ return d.consumeToken(MessageOpen, 1, 0), nil
+ case '[':
+ d.pushOpenStack(ch)
+ return d.consumeToken(ListOpen, 1, 0), nil
+ default:
+ return d.parseScalar()
+ }
+
+ case Scalar:
+ openKind, closeCh := d.currentOpenKind()
+ switch openKind {
+ case bof:
+ // Top level message.
+ // Next token can be EOF, comma, semicolon or Name.
+ if isEOF {
+ return d.consumeToken(EOF, 0, 0), nil
+ }
+ switch d.in[0] {
+ case ',':
+ return d.consumeToken(comma, 1, 0), nil
+ case ';':
+ return d.consumeToken(semicolon, 1, 0), nil
+ default:
+ return d.parseFieldName()
+ }
+
+ case MessageOpen:
+ // Next token can be MessageClose, comma, semicolon or Name.
+ if isEOF {
+ return Token{}, ErrUnexpectedEOF
+ }
+ switch ch := d.in[0]; ch {
+ case closeCh:
+ d.popOpenStack()
+ return d.consumeToken(MessageClose, 1, 0), nil
+ case otherCloseChar[closeCh]:
+ return Token{}, d.newSyntaxError(mismatchedFmt, ch)
+ case ',':
+ return d.consumeToken(comma, 1, 0), nil
+ case ';':
+ return d.consumeToken(semicolon, 1, 0), nil
+ default:
+ return d.parseFieldName()
+ }
+
+ case ListOpen:
+ // Next token can be ListClose or comma.
+ if isEOF {
+ return Token{}, ErrUnexpectedEOF
+ }
+ switch ch := d.in[0]; ch {
+ case ']':
+ d.popOpenStack()
+ return d.consumeToken(ListClose, 1, 0), nil
+ case ',':
+ return d.consumeToken(comma, 1, 0), nil
+ default:
+ return Token{}, d.newSyntaxError(unexpectedFmt, ch)
+ }
+ }
+
+ case MessageOpen:
+ // Next token can be MessageClose or Name.
+ if isEOF {
+ return Token{}, ErrUnexpectedEOF
+ }
+ _, closeCh := d.currentOpenKind()
+ switch ch := d.in[0]; ch {
+ case closeCh:
+ d.popOpenStack()
+ return d.consumeToken(MessageClose, 1, 0), nil
+ case otherCloseChar[closeCh]:
+ return Token{}, d.newSyntaxError(mismatchedFmt, ch)
+ default:
+ return d.parseFieldName()
+ }
+
+ case MessageClose:
+ openKind, closeCh := d.currentOpenKind()
+ switch openKind {
+ case bof:
+ // Top level message.
+ // Next token can be EOF, comma, semicolon or Name.
+ if isEOF {
+ return d.consumeToken(EOF, 0, 0), nil
+ }
+ switch ch := d.in[0]; ch {
+ case ',':
+ return d.consumeToken(comma, 1, 0), nil
+ case ';':
+ return d.consumeToken(semicolon, 1, 0), nil
+ default:
+ return d.parseFieldName()
+ }
+
+ case MessageOpen:
+ // Next token can be MessageClose, comma, semicolon or Name.
+ if isEOF {
+ return Token{}, ErrUnexpectedEOF
+ }
+ switch ch := d.in[0]; ch {
+ case closeCh:
+ d.popOpenStack()
+ return d.consumeToken(MessageClose, 1, 0), nil
+ case otherCloseChar[closeCh]:
+ return Token{}, d.newSyntaxError(mismatchedFmt, ch)
+ case ',':
+ return d.consumeToken(comma, 1, 0), nil
+ case ';':
+ return d.consumeToken(semicolon, 1, 0), nil
+ default:
+ return d.parseFieldName()
+ }
+
+ case ListOpen:
+ // Next token can be ListClose or comma
+ if isEOF {
+ return Token{}, ErrUnexpectedEOF
+ }
+ switch ch := d.in[0]; ch {
+ case closeCh:
+ d.popOpenStack()
+ return d.consumeToken(ListClose, 1, 0), nil
+ case ',':
+ return d.consumeToken(comma, 1, 0), nil
+ default:
+ return Token{}, d.newSyntaxError(unexpectedFmt, ch)
+ }
+ }
+
+ case ListOpen:
+ // Next token can be ListClose, MessageStart or Scalar.
+ if isEOF {
+ return Token{}, ErrUnexpectedEOF
+ }
+ switch ch := d.in[0]; ch {
+ case ']':
+ d.popOpenStack()
+ return d.consumeToken(ListClose, 1, 0), nil
+ case '{', '<':
+ d.pushOpenStack(ch)
+ return d.consumeToken(MessageOpen, 1, 0), nil
+ default:
+ return d.parseScalar()
+ }
+
+ case ListClose:
+ openKind, closeCh := d.currentOpenKind()
+ switch openKind {
+ case bof:
+ // Top level message.
+ // Next token can be EOF, comma, semicolon or Name.
+ if isEOF {
+ return d.consumeToken(EOF, 0, 0), nil
+ }
+ switch ch := d.in[0]; ch {
+ case ',':
+ return d.consumeToken(comma, 1, 0), nil
+ case ';':
+ return d.consumeToken(semicolon, 1, 0), nil
+ default:
+ return d.parseFieldName()
+ }
+
+ case MessageOpen:
+ // Next token can be MessageClose, comma, semicolon or Name.
+ if isEOF {
+ return Token{}, ErrUnexpectedEOF
+ }
+ switch ch := d.in[0]; ch {
+ case closeCh:
+ d.popOpenStack()
+ return d.consumeToken(MessageClose, 1, 0), nil
+ case otherCloseChar[closeCh]:
+ return Token{}, d.newSyntaxError(mismatchedFmt, ch)
+ case ',':
+ return d.consumeToken(comma, 1, 0), nil
+ case ';':
+ return d.consumeToken(semicolon, 1, 0), nil
+ default:
+ return d.parseFieldName()
+ }
+
+ default:
+ // It is not possible to have this case. Let it panic below.
+ }
+
+ case comma, semicolon:
+ openKind, closeCh := d.currentOpenKind()
+ switch openKind {
+ case bof:
+ // Top level message. Next token can be EOF or Name.
+ if isEOF {
+ return d.consumeToken(EOF, 0, 0), nil
+ }
+ return d.parseFieldName()
+
+ case MessageOpen:
+ // Next token can be MessageClose or Name.
+ if isEOF {
+ return Token{}, ErrUnexpectedEOF
+ }
+ switch ch := d.in[0]; ch {
+ case closeCh:
+ d.popOpenStack()
+ return d.consumeToken(MessageClose, 1, 0), nil
+ case otherCloseChar[closeCh]:
+ return Token{}, d.newSyntaxError(mismatchedFmt, ch)
+ default:
+ return d.parseFieldName()
+ }
+
+ case ListOpen:
+ if lastKind == semicolon {
+ // It is not be possible to have this case as logic here
+ // should not have produced a semicolon Token when inside a
+ // list. Let it panic below.
+ break
+ }
+ // Next token can be MessageOpen or Scalar.
+ if isEOF {
+ return Token{}, ErrUnexpectedEOF
+ }
+ switch ch := d.in[0]; ch {
+ case '{', '<':
+ d.pushOpenStack(ch)
+ return d.consumeToken(MessageOpen, 1, 0), nil
+ default:
+ return d.parseScalar()
+ }
+ }
+ }
+
+ line, column := d.Position(len(d.orig) - len(d.in))
+ panic(fmt.Sprintf("Decoder.parseNext: bug at handling line %d:%d with lastKind=%v", line, column, lastKind))
+}
+
+var otherCloseChar = map[byte]byte{
+ '}': '>',
+ '>': '}',
+}
+
+// currentOpenKind indicates whether current position is inside a message, list
+// or top-level message by returning MessageOpen, ListOpen or bof respectively.
+// If the returned kind is either a MessageOpen or ListOpen, it also returns the
+// corresponding closing character.
+func (d *Decoder) currentOpenKind() (Kind, byte) {
+ if len(d.openStack) == 0 {
+ return bof, 0
+ }
+ openCh := d.openStack[len(d.openStack)-1]
+ switch openCh {
+ case '{':
+ return MessageOpen, '}'
+ case '<':
+ return MessageOpen, '>'
+ case '[':
+ return ListOpen, ']'
+ }
+ panic(fmt.Sprintf("Decoder: openStack contains invalid byte %s", string(openCh)))
+}
+
+func (d *Decoder) pushOpenStack(ch byte) {
+ d.openStack = append(d.openStack, ch)
+}
+
+func (d *Decoder) popOpenStack() {
+ d.openStack = d.openStack[:len(d.openStack)-1]
+}
+
+// parseFieldName parses field name and separator.
+func (d *Decoder) parseFieldName() (tok Token, err error) {
+ defer func() {
+ if err == nil && d.tryConsumeChar(':') {
+ tok.attrs |= hasSeparator
+ }
+ }()
+
+ // Extension or Any type URL.
+ if d.in[0] == '[' {
+ return d.parseTypeName()
+ }
+
+ // Identifier.
+ if size := parseIdent(d.in, false); size > 0 {
+ return d.consumeToken(Name, size, uint8(IdentName)), nil
+ }
+
+ // Field number. Identify if input is a valid number that is not negative
+ // and is decimal integer within 32-bit range.
+ if num := parseNumber(d.in); num.size > 0 {
+ if !num.neg && num.kind == numDec {
+ if _, err := strconv.ParseInt(string(d.in[:num.size]), 10, 32); err == nil {
+ return d.consumeToken(Name, num.size, uint8(FieldNumber)), nil
+ }
+ }
+ return Token{}, d.newSyntaxError("invalid field number: %s", d.in[:num.size])
+ }
+
+ return Token{}, d.newSyntaxError("invalid field name: %s", errRegexp.Find(d.in))
+}
+
+// parseTypeName parses Any type URL or extension field name. The name is
+// enclosed in [ and ] characters. The C++ parser does not handle many legal URL
+// strings. This implementation is more liberal and allows for the pattern
+// ^[-_a-zA-Z0-9]+([./][-_a-zA-Z0-9]+)*`). Whitespaces and comments are allowed
+// in between [ ], '.', '/' and the sub names.
+func (d *Decoder) parseTypeName() (Token, error) {
+ startPos := len(d.orig) - len(d.in)
+ // Use alias s to advance first in order to use d.in for error handling.
+ // Caller already checks for [ as first character.
+ s := consume(d.in[1:], 0)
+ if len(s) == 0 {
+ return Token{}, ErrUnexpectedEOF
+ }
+
+ var name []byte
+ for len(s) > 0 && isTypeNameChar(s[0]) {
+ name = append(name, s[0])
+ s = s[1:]
+ }
+ s = consume(s, 0)
+
+ var closed bool
+ for len(s) > 0 && !closed {
+ switch {
+ case s[0] == ']':
+ s = s[1:]
+ closed = true
+
+ case s[0] == '/', s[0] == '.':
+ if len(name) > 0 && (name[len(name)-1] == '/' || name[len(name)-1] == '.') {
+ return Token{}, d.newSyntaxError("invalid type URL/extension field name: %s",
+ d.orig[startPos:len(d.orig)-len(s)+1])
+ }
+ name = append(name, s[0])
+ s = s[1:]
+ s = consume(s, 0)
+ for len(s) > 0 && isTypeNameChar(s[0]) {
+ name = append(name, s[0])
+ s = s[1:]
+ }
+ s = consume(s, 0)
+
+ default:
+ return Token{}, d.newSyntaxError(
+ "invalid type URL/extension field name: %s", d.orig[startPos:len(d.orig)-len(s)+1])
+ }
+ }
+
+ if !closed {
+ return Token{}, ErrUnexpectedEOF
+ }
+
+ // First character cannot be '.'. Last character cannot be '.' or '/'.
+ size := len(name)
+ if size == 0 || name[0] == '.' || name[size-1] == '.' || name[size-1] == '/' {
+ return Token{}, d.newSyntaxError("invalid type URL/extension field name: %s",
+ d.orig[startPos:len(d.orig)-len(s)])
+ }
+
+ d.in = s
+ endPos := len(d.orig) - len(d.in)
+ d.consume(0)
+
+ return Token{
+ kind: Name,
+ attrs: uint8(TypeName),
+ pos: startPos,
+ raw: d.orig[startPos:endPos],
+ str: string(name),
+ }, nil
+}
+
+func isTypeNameChar(b byte) bool {
+ return (b == '-' || b == '_' ||
+ ('0' <= b && b <= '9') ||
+ ('a' <= b && b <= 'z') ||
+ ('A' <= b && b <= 'Z'))
+}
+
+func isWhiteSpace(b byte) bool {
+ switch b {
+ case ' ', '\n', '\r', '\t':
+ return true
+ default:
+ return false
+ }
+}
+
+// parseIdent parses an unquoted proto identifier and returns size.
+// If allowNeg is true, it allows '-' to be the first character in the
+// identifier. This is used when parsing literal values like -infinity, etc.
+// Regular expression matches an identifier: `^[_a-zA-Z][_a-zA-Z0-9]*`
+func parseIdent(input []byte, allowNeg bool) int {
+ var size int
+
+ s := input
+ if len(s) == 0 {
+ return 0
+ }
+
+ if allowNeg && s[0] == '-' {
+ s = s[1:]
+ size++
+ if len(s) == 0 {
+ return 0
+ }
+ }
+
+ switch {
+ case s[0] == '_',
+ 'a' <= s[0] && s[0] <= 'z',
+ 'A' <= s[0] && s[0] <= 'Z':
+ s = s[1:]
+ size++
+ default:
+ return 0
+ }
+
+ for len(s) > 0 && (s[0] == '_' ||
+ 'a' <= s[0] && s[0] <= 'z' ||
+ 'A' <= s[0] && s[0] <= 'Z' ||
+ '0' <= s[0] && s[0] <= '9') {
+ s = s[1:]
+ size++
+ }
+
+ if len(s) > 0 && !isDelim(s[0]) {
+ return 0
+ }
+
+ return size
+}
+
+// parseScalar parses for a string, literal or number value.
+func (d *Decoder) parseScalar() (Token, error) {
+ if d.in[0] == '"' || d.in[0] == '\'' {
+ return d.parseStringValue()
+ }
+
+ if tok, ok := d.parseLiteralValue(); ok {
+ return tok, nil
+ }
+
+ if tok, ok := d.parseNumberValue(); ok {
+ return tok, nil
+ }
+
+ return Token{}, d.newSyntaxError("invalid scalar value: %s", errRegexp.Find(d.in))
+}
+
+// parseLiteralValue parses a literal value. A literal value is used for
+// bools, special floats and enums. This function simply identifies that the
+// field value is a literal.
+func (d *Decoder) parseLiteralValue() (Token, bool) {
+ size := parseIdent(d.in, true)
+ if size == 0 {
+ return Token{}, false
+ }
+ return d.consumeToken(Scalar, size, literalValue), true
+}
+
+// consumeToken constructs a Token for given Kind from d.in and consumes given
+// size-length from it.
+func (d *Decoder) consumeToken(kind Kind, size int, attrs uint8) Token {
+ // Important to compute raw and pos before consuming.
+ tok := Token{
+ kind: kind,
+ attrs: attrs,
+ pos: len(d.orig) - len(d.in),
+ raw: d.in[:size],
+ }
+ d.consume(size)
+ return tok
+}
+
+// newSyntaxError returns a syntax error with line and column information for
+// current position.
+func (d *Decoder) newSyntaxError(f string, x ...interface{}) error {
+ e := errors.New(f, x...)
+ line, column := d.Position(len(d.orig) - len(d.in))
+ return errors.New("syntax error (line %d:%d): %v", line, column, e)
+}
+
+// Position returns line and column number of given index of the original input.
+// It will panic if index is out of range.
+func (d *Decoder) Position(idx int) (line int, column int) {
+ b := d.orig[:idx]
+ line = bytes.Count(b, []byte("\n")) + 1
+ if i := bytes.LastIndexByte(b, '\n'); i >= 0 {
+ b = b[i+1:]
+ }
+ column = utf8.RuneCount(b) + 1 // ignore multi-rune characters
+ return line, column
+}
+
+func (d *Decoder) tryConsumeChar(c byte) bool {
+ if len(d.in) > 0 && d.in[0] == c {
+ d.consume(1)
+ return true
+ }
+ return false
+}
+
+// consume consumes n bytes of input and any subsequent whitespace or comments.
+func (d *Decoder) consume(n int) {
+ d.in = consume(d.in, n)
+ return
+}
+
+// consume consumes n bytes of input and any subsequent whitespace or comments.
+func consume(b []byte, n int) []byte {
+ b = b[n:]
+ for len(b) > 0 {
+ switch b[0] {
+ case ' ', '\n', '\r', '\t':
+ b = b[1:]
+ case '#':
+ if i := bytes.IndexByte(b, '\n'); i >= 0 {
+ b = b[i+len("\n"):]
+ } else {
+ b = nil
+ }
+ default:
+ return b
+ }
+ }
+ return b
+}
+
+// Any sequence that looks like a non-delimiter (for error reporting).
+var errRegexp = regexp.MustCompile(`^([-+._a-zA-Z0-9\/]+|.)`)
+
+// isDelim returns true if given byte is a delimiter character.
+func isDelim(c byte) bool {
+ return !(c == '-' || c == '+' || c == '.' || c == '_' ||
+ ('a' <= c && c <= 'z') ||
+ ('A' <= c && c <= 'Z') ||
+ ('0' <= c && c <= '9'))
+}
generated by cgit v1.2.3-54-g00ecf (git 2.39.0) at 2024-10-20 00:29:11 +0000