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-rw-r--r--vendor/google.golang.org/protobuf/internal/encoding/text/decode_number.go190
1 files changed, 190 insertions, 0 deletions
diff --git a/vendor/google.golang.org/protobuf/internal/encoding/text/decode_number.go b/vendor/google.golang.org/protobuf/internal/encoding/text/decode_number.go
new file mode 100644
index 0000000000..f2d90b7899
--- /dev/null
+++ b/vendor/google.golang.org/protobuf/internal/encoding/text/decode_number.go
@@ -0,0 +1,190 @@
+// 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
+
+// parseNumberValue parses a number from the input and returns a Token object.
+func (d *Decoder) parseNumberValue() (Token, bool) {
+ in := d.in
+ num := parseNumber(in)
+ if num.size == 0 {
+ return Token{}, false
+ }
+ numAttrs := num.kind
+ if num.neg {
+ numAttrs |= isNegative
+ }
+ strSize := num.size
+ last := num.size - 1
+ if num.kind == numFloat && (d.in[last] == 'f' || d.in[last] == 'F') {
+ strSize = last
+ }
+ tok := Token{
+ kind: Scalar,
+ attrs: numberValue,
+ pos: len(d.orig) - len(d.in),
+ raw: d.in[:num.size],
+ str: string(d.in[:strSize]),
+ numAttrs: numAttrs,
+ }
+ d.consume(num.size)
+ return tok, true
+}
+
+const (
+ numDec uint8 = (1 << iota) / 2
+ numHex
+ numOct
+ numFloat
+)
+
+// number is the result of parsing out a valid number from parseNumber. It
+// contains data for doing float or integer conversion via the strconv package
+// in conjunction with the input bytes.
+type number struct {
+ kind uint8
+ neg bool
+ size int
+}
+
+// parseNumber constructs a number object from given input. It allows for the
+// following patterns:
+// integer: ^-?([1-9][0-9]*|0[xX][0-9a-fA-F]+|0[0-7]*)
+// float: ^-?((0|[1-9][0-9]*)?([.][0-9]*)?([eE][+-]?[0-9]+)?[fF]?)
+// It also returns the number of parsed bytes for the given number, 0 if it is
+// not a number.
+func parseNumber(input []byte) number {
+ kind := numDec
+ var size int
+ var neg bool
+
+ s := input
+ if len(s) == 0 {
+ return number{}
+ }
+
+ // Optional -
+ if s[0] == '-' {
+ neg = true
+ s = s[1:]
+ size++
+ if len(s) == 0 {
+ return number{}
+ }
+ }
+
+ // C++ allows for whitespace and comments in between the negative sign and
+ // the rest of the number. This logic currently does not but is consistent
+ // with v1.
+
+ switch {
+ case s[0] == '0':
+ if len(s) > 1 {
+ switch {
+ case s[1] == 'x' || s[1] == 'X':
+ // Parse as hex number.
+ kind = numHex
+ n := 2
+ s = s[2:]
+ for len(s) > 0 && (('0' <= s[0] && s[0] <= '9') ||
+ ('a' <= s[0] && s[0] <= 'f') ||
+ ('A' <= s[0] && s[0] <= 'F')) {
+ s = s[1:]
+ n++
+ }
+ if n == 2 {
+ return number{}
+ }
+ size += n
+
+ case '0' <= s[1] && s[1] <= '7':
+ // Parse as octal number.
+ kind = numOct
+ n := 2
+ s = s[2:]
+ for len(s) > 0 && '0' <= s[0] && s[0] <= '7' {
+ s = s[1:]
+ n++
+ }
+ size += n
+ }
+
+ if kind&(numHex|numOct) > 0 {
+ if len(s) > 0 && !isDelim(s[0]) {
+ return number{}
+ }
+ return number{kind: kind, neg: neg, size: size}
+ }
+ }
+ s = s[1:]
+ size++
+
+ case '1' <= s[0] && s[0] <= '9':
+ n := 1
+ s = s[1:]
+ for len(s) > 0 && '0' <= s[0] && s[0] <= '9' {
+ s = s[1:]
+ n++
+ }
+ size += n
+
+ case s[0] == '.':
+ // Set kind to numFloat to signify the intent to parse as float. And
+ // that it needs to have other digits after '.'.
+ kind = numFloat
+
+ default:
+ return number{}
+ }
+
+ // . followed by 0 or more digits.
+ if len(s) > 0 && s[0] == '.' {
+ n := 1
+ s = s[1:]
+ // If decimal point was before any digits, it should be followed by
+ // other digits.
+ if len(s) == 0 && kind == numFloat {
+ return number{}
+ }
+ for len(s) > 0 && '0' <= s[0] && s[0] <= '9' {
+ s = s[1:]
+ n++
+ }
+ size += n
+ kind = numFloat
+ }
+
+ // e or E followed by an optional - or + and 1 or more digits.
+ if len(s) >= 2 && (s[0] == 'e' || s[0] == 'E') {
+ kind = numFloat
+ s = s[1:]
+ n := 1
+ if s[0] == '+' || s[0] == '-' {
+ s = s[1:]
+ n++
+ if len(s) == 0 {
+ return number{}
+ }
+ }
+ for len(s) > 0 && '0' <= s[0] && s[0] <= '9' {
+ s = s[1:]
+ n++
+ }
+ size += n
+ }
+
+ // Optional suffix f or F for floats.
+ if len(s) > 0 && (s[0] == 'f' || s[0] == 'F') {
+ kind = numFloat
+ s = s[1:]
+ size++
+ }
+
+ // Check that next byte is a delimiter or it is at the end.
+ if len(s) > 0 && !isDelim(s[0]) {
+ return number{}
+ }
+
+ return number{kind: kind, neg: neg, size: size}
+}