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-rw-r--r--vendor/google.golang.org/protobuf/internal/encoding/defval/default.go213
1 files changed, 213 insertions, 0 deletions
diff --git a/vendor/google.golang.org/protobuf/internal/encoding/defval/default.go b/vendor/google.golang.org/protobuf/internal/encoding/defval/default.go
new file mode 100644
index 00000000..fdd9b13f
--- /dev/null
+++ b/vendor/google.golang.org/protobuf/internal/encoding/defval/default.go
@@ -0,0 +1,213 @@
+// 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 defval marshals and unmarshals textual forms of default values.
+//
+// This package handles both the form historically used in Go struct field tags
+// and also the form used by google.protobuf.FieldDescriptorProto.default_value
+// since they differ in superficial ways.
+package defval
+
+import (
+ "fmt"
+ "math"
+ "strconv"
+
+ ptext "google.golang.org/protobuf/internal/encoding/text"
+ errors "google.golang.org/protobuf/internal/errors"
+ pref "google.golang.org/protobuf/reflect/protoreflect"
+)
+
+// Format is the serialization format used to represent the default value.
+type Format int
+
+const (
+ _ Format = iota
+
+ // Descriptor uses the serialization format that protoc uses with the
+ // google.protobuf.FieldDescriptorProto.default_value field.
+ Descriptor
+
+ // GoTag uses the historical serialization format in Go struct field tags.
+ GoTag
+)
+
+// Unmarshal deserializes the default string s according to the given kind k.
+// When k is an enum, a list of enum value descriptors must be provided.
+func Unmarshal(s string, k pref.Kind, evs pref.EnumValueDescriptors, f Format) (pref.Value, pref.EnumValueDescriptor, error) {
+ switch k {
+ case pref.BoolKind:
+ if f == GoTag {
+ switch s {
+ case "1":
+ return pref.ValueOfBool(true), nil, nil
+ case "0":
+ return pref.ValueOfBool(false), nil, nil
+ }
+ } else {
+ switch s {
+ case "true":
+ return pref.ValueOfBool(true), nil, nil
+ case "false":
+ return pref.ValueOfBool(false), nil, nil
+ }
+ }
+ case pref.EnumKind:
+ if f == GoTag {
+ // Go tags use the numeric form of the enum value.
+ if n, err := strconv.ParseInt(s, 10, 32); err == nil {
+ if ev := evs.ByNumber(pref.EnumNumber(n)); ev != nil {
+ return pref.ValueOfEnum(ev.Number()), ev, nil
+ }
+ }
+ } else {
+ // Descriptor default_value use the enum identifier.
+ ev := evs.ByName(pref.Name(s))
+ if ev != nil {
+ return pref.ValueOfEnum(ev.Number()), ev, nil
+ }
+ }
+ case pref.Int32Kind, pref.Sint32Kind, pref.Sfixed32Kind:
+ if v, err := strconv.ParseInt(s, 10, 32); err == nil {
+ return pref.ValueOfInt32(int32(v)), nil, nil
+ }
+ case pref.Int64Kind, pref.Sint64Kind, pref.Sfixed64Kind:
+ if v, err := strconv.ParseInt(s, 10, 64); err == nil {
+ return pref.ValueOfInt64(int64(v)), nil, nil
+ }
+ case pref.Uint32Kind, pref.Fixed32Kind:
+ if v, err := strconv.ParseUint(s, 10, 32); err == nil {
+ return pref.ValueOfUint32(uint32(v)), nil, nil
+ }
+ case pref.Uint64Kind, pref.Fixed64Kind:
+ if v, err := strconv.ParseUint(s, 10, 64); err == nil {
+ return pref.ValueOfUint64(uint64(v)), nil, nil
+ }
+ case pref.FloatKind, pref.DoubleKind:
+ var v float64
+ var err error
+ switch s {
+ case "-inf":
+ v = math.Inf(-1)
+ case "inf":
+ v = math.Inf(+1)
+ case "nan":
+ v = math.NaN()
+ default:
+ v, err = strconv.ParseFloat(s, 64)
+ }
+ if err == nil {
+ if k == pref.FloatKind {
+ return pref.ValueOfFloat32(float32(v)), nil, nil
+ } else {
+ return pref.ValueOfFloat64(float64(v)), nil, nil
+ }
+ }
+ case pref.StringKind:
+ // String values are already unescaped and can be used as is.
+ return pref.ValueOfString(s), nil, nil
+ case pref.BytesKind:
+ if b, ok := unmarshalBytes(s); ok {
+ return pref.ValueOfBytes(b), nil, nil
+ }
+ }
+ return pref.Value{}, nil, errors.New("could not parse value for %v: %q", k, s)
+}
+
+// Marshal serializes v as the default string according to the given kind k.
+// When specifying the Descriptor format for an enum kind, the associated
+// enum value descriptor must be provided.
+func Marshal(v pref.Value, ev pref.EnumValueDescriptor, k pref.Kind, f Format) (string, error) {
+ switch k {
+ case pref.BoolKind:
+ if f == GoTag {
+ if v.Bool() {
+ return "1", nil
+ } else {
+ return "0", nil
+ }
+ } else {
+ if v.Bool() {
+ return "true", nil
+ } else {
+ return "false", nil
+ }
+ }
+ case pref.EnumKind:
+ if f == GoTag {
+ return strconv.FormatInt(int64(v.Enum()), 10), nil
+ } else {
+ return string(ev.Name()), nil
+ }
+ case pref.Int32Kind, pref.Sint32Kind, pref.Sfixed32Kind, pref.Int64Kind, pref.Sint64Kind, pref.Sfixed64Kind:
+ return strconv.FormatInt(v.Int(), 10), nil
+ case pref.Uint32Kind, pref.Fixed32Kind, pref.Uint64Kind, pref.Fixed64Kind:
+ return strconv.FormatUint(v.Uint(), 10), nil
+ case pref.FloatKind, pref.DoubleKind:
+ f := v.Float()
+ switch {
+ case math.IsInf(f, -1):
+ return "-inf", nil
+ case math.IsInf(f, +1):
+ return "inf", nil
+ case math.IsNaN(f):
+ return "nan", nil
+ default:
+ if k == pref.FloatKind {
+ return strconv.FormatFloat(f, 'g', -1, 32), nil
+ } else {
+ return strconv.FormatFloat(f, 'g', -1, 64), nil
+ }
+ }
+ case pref.StringKind:
+ // String values are serialized as is without any escaping.
+ return v.String(), nil
+ case pref.BytesKind:
+ if s, ok := marshalBytes(v.Bytes()); ok {
+ return s, nil
+ }
+ }
+ return "", errors.New("could not format value for %v: %v", k, v)
+}
+
+// unmarshalBytes deserializes bytes by applying C unescaping.
+func unmarshalBytes(s string) ([]byte, bool) {
+ // Bytes values use the same escaping as the text format,
+ // however they lack the surrounding double quotes.
+ v, err := ptext.UnmarshalString(`"` + s + `"`)
+ if err != nil {
+ return nil, false
+ }
+ return []byte(v), true
+}
+
+// marshalBytes serializes bytes by using C escaping.
+// To match the exact output of protoc, this is identical to the
+// CEscape function in strutil.cc of the protoc source code.
+func marshalBytes(b []byte) (string, bool) {
+ var s []byte
+ for _, c := range b {
+ switch c {
+ case '\n':
+ s = append(s, `\n`...)
+ case '\r':
+ s = append(s, `\r`...)
+ case '\t':
+ s = append(s, `\t`...)
+ case '"':
+ s = append(s, `\"`...)
+ case '\'':
+ s = append(s, `\'`...)
+ case '\\':
+ s = append(s, `\\`...)
+ default:
+ if printableASCII := c >= 0x20 && c <= 0x7e; printableASCII {
+ s = append(s, c)
+ } else {
+ s = append(s, fmt.Sprintf(`\%03o`, c)...)
+ }
+ }
+ }
+ return string(s), true
+}