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authorWim <wim@42.be>2020-08-10 00:29:54 +0200
committerGitHub <noreply@github.com>2020-08-10 00:29:54 +0200
commit4e50fd864921c556988c919269448efdb90fa961 (patch)
treea3625f03f8de3c4f3841364000a4ea3aa42c1533 /vendor/google.golang.org/protobuf/internal/encoding/messageset
parentdfdffa0027334e55ce213fc6eb62206dbf48baf6 (diff)
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Use mattermost v5 module (#1192)
Diffstat (limited to 'vendor/google.golang.org/protobuf/internal/encoding/messageset')
-rw-r--r--vendor/google.golang.org/protobuf/internal/encoding/messageset/messageset.go258
1 files changed, 258 insertions, 0 deletions
diff --git a/vendor/google.golang.org/protobuf/internal/encoding/messageset/messageset.go b/vendor/google.golang.org/protobuf/internal/encoding/messageset/messageset.go
new file mode 100644
index 00000000..b1eeea50
--- /dev/null
+++ b/vendor/google.golang.org/protobuf/internal/encoding/messageset/messageset.go
@@ -0,0 +1,258 @@
+// Copyright 2019 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 messageset encodes and decodes the obsolete MessageSet wire format.
+package messageset
+
+import (
+ "math"
+
+ "google.golang.org/protobuf/encoding/protowire"
+ "google.golang.org/protobuf/internal/errors"
+ pref "google.golang.org/protobuf/reflect/protoreflect"
+ preg "google.golang.org/protobuf/reflect/protoregistry"
+)
+
+// The MessageSet wire format is equivalent to a message defiend as follows,
+// where each Item defines an extension field with a field number of 'type_id'
+// and content of 'message'. MessageSet extensions must be non-repeated message
+// fields.
+//
+// message MessageSet {
+// repeated group Item = 1 {
+// required int32 type_id = 2;
+// required string message = 3;
+// }
+// }
+const (
+ FieldItem = protowire.Number(1)
+ FieldTypeID = protowire.Number(2)
+ FieldMessage = protowire.Number(3)
+)
+
+// ExtensionName is the field name for extensions of MessageSet.
+//
+// A valid MessageSet extension must be of the form:
+// message MyMessage {
+// extend proto2.bridge.MessageSet {
+// optional MyMessage message_set_extension = 1234;
+// }
+// ...
+// }
+const ExtensionName = "message_set_extension"
+
+// IsMessageSet returns whether the message uses the MessageSet wire format.
+func IsMessageSet(md pref.MessageDescriptor) bool {
+ xmd, ok := md.(interface{ IsMessageSet() bool })
+ return ok && xmd.IsMessageSet()
+}
+
+// IsMessageSetExtension reports this field extends a MessageSet.
+func IsMessageSetExtension(fd pref.FieldDescriptor) bool {
+ if fd.Name() != ExtensionName {
+ return false
+ }
+ if fd.FullName().Parent() != fd.Message().FullName() {
+ return false
+ }
+ return IsMessageSet(fd.ContainingMessage())
+}
+
+// FindMessageSetExtension locates a MessageSet extension field by name.
+// In text and JSON formats, the extension name used is the message itself.
+// The extension field name is derived by appending ExtensionName.
+func FindMessageSetExtension(r preg.ExtensionTypeResolver, s pref.FullName) (pref.ExtensionType, error) {
+ name := s.Append(ExtensionName)
+ xt, err := r.FindExtensionByName(name)
+ if err != nil {
+ if err == preg.NotFound {
+ return nil, err
+ }
+ return nil, errors.Wrap(err, "%q", name)
+ }
+ if !IsMessageSetExtension(xt.TypeDescriptor()) {
+ return nil, preg.NotFound
+ }
+ return xt, nil
+}
+
+// SizeField returns the size of a MessageSet item field containing an extension
+// with the given field number, not counting the contents of the message subfield.
+func SizeField(num protowire.Number) int {
+ return 2*protowire.SizeTag(FieldItem) + protowire.SizeTag(FieldTypeID) + protowire.SizeVarint(uint64(num))
+}
+
+// Unmarshal parses a MessageSet.
+//
+// It calls fn with the type ID and value of each item in the MessageSet.
+// Unknown fields are discarded.
+//
+// If wantLen is true, the item values include the varint length prefix.
+// This is ugly, but simplifies the fast-path decoder in internal/impl.
+func Unmarshal(b []byte, wantLen bool, fn func(typeID protowire.Number, value []byte) error) error {
+ for len(b) > 0 {
+ num, wtyp, n := protowire.ConsumeTag(b)
+ if n < 0 {
+ return protowire.ParseError(n)
+ }
+ b = b[n:]
+ if num != FieldItem || wtyp != protowire.StartGroupType {
+ n := protowire.ConsumeFieldValue(num, wtyp, b)
+ if n < 0 {
+ return protowire.ParseError(n)
+ }
+ b = b[n:]
+ continue
+ }
+ typeID, value, n, err := ConsumeFieldValue(b, wantLen)
+ if err != nil {
+ return err
+ }
+ b = b[n:]
+ if typeID == 0 {
+ continue
+ }
+ if err := fn(typeID, value); err != nil {
+ return err
+ }
+ }
+ return nil
+}
+
+// ConsumeFieldValue parses b as a MessageSet item field value until and including
+// the trailing end group marker. It assumes the start group tag has already been parsed.
+// It returns the contents of the type_id and message subfields and the total
+// item length.
+//
+// If wantLen is true, the returned message value includes the length prefix.
+func ConsumeFieldValue(b []byte, wantLen bool) (typeid protowire.Number, message []byte, n int, err error) {
+ ilen := len(b)
+ for {
+ num, wtyp, n := protowire.ConsumeTag(b)
+ if n < 0 {
+ return 0, nil, 0, protowire.ParseError(n)
+ }
+ b = b[n:]
+ switch {
+ case num == FieldItem && wtyp == protowire.EndGroupType:
+ if wantLen && len(message) == 0 {
+ // The message field was missing, which should never happen.
+ // Be prepared for this case anyway.
+ message = protowire.AppendVarint(message, 0)
+ }
+ return typeid, message, ilen - len(b), nil
+ case num == FieldTypeID && wtyp == protowire.VarintType:
+ v, n := protowire.ConsumeVarint(b)
+ if n < 0 {
+ return 0, nil, 0, protowire.ParseError(n)
+ }
+ b = b[n:]
+ if v < 1 || v > math.MaxInt32 {
+ return 0, nil, 0, errors.New("invalid type_id in message set")
+ }
+ typeid = protowire.Number(v)
+ case num == FieldMessage && wtyp == protowire.BytesType:
+ m, n := protowire.ConsumeBytes(b)
+ if n < 0 {
+ return 0, nil, 0, protowire.ParseError(n)
+ }
+ if message == nil {
+ if wantLen {
+ message = b[:n:n]
+ } else {
+ message = m[:len(m):len(m)]
+ }
+ } else {
+ // This case should never happen in practice, but handle it for
+ // correctness: The MessageSet item contains multiple message
+ // fields, which need to be merged.
+ //
+ // In the case where we're returning the length, this becomes
+ // quite inefficient since we need to strip the length off
+ // the existing data and reconstruct it with the combined length.
+ if wantLen {
+ _, nn := protowire.ConsumeVarint(message)
+ m0 := message[nn:]
+ message = nil
+ message = protowire.AppendVarint(message, uint64(len(m0)+len(m)))
+ message = append(message, m0...)
+ message = append(message, m...)
+ } else {
+ message = append(message, m...)
+ }
+ }
+ b = b[n:]
+ default:
+ // We have no place to put it, so we just ignore unknown fields.
+ n := protowire.ConsumeFieldValue(num, wtyp, b)
+ if n < 0 {
+ return 0, nil, 0, protowire.ParseError(n)
+ }
+ b = b[n:]
+ }
+ }
+}
+
+// AppendFieldStart appends the start of a MessageSet item field containing
+// an extension with the given number. The caller must add the message
+// subfield (including the tag).
+func AppendFieldStart(b []byte, num protowire.Number) []byte {
+ b = protowire.AppendTag(b, FieldItem, protowire.StartGroupType)
+ b = protowire.AppendTag(b, FieldTypeID, protowire.VarintType)
+ b = protowire.AppendVarint(b, uint64(num))
+ return b
+}
+
+// AppendFieldEnd appends the trailing end group marker for a MessageSet item field.
+func AppendFieldEnd(b []byte) []byte {
+ return protowire.AppendTag(b, FieldItem, protowire.EndGroupType)
+}
+
+// SizeUnknown returns the size of an unknown fields section in MessageSet format.
+//
+// See AppendUnknown.
+func SizeUnknown(unknown []byte) (size int) {
+ for len(unknown) > 0 {
+ num, typ, n := protowire.ConsumeTag(unknown)
+ if n < 0 || typ != protowire.BytesType {
+ return 0
+ }
+ unknown = unknown[n:]
+ _, n = protowire.ConsumeBytes(unknown)
+ if n < 0 {
+ return 0
+ }
+ unknown = unknown[n:]
+ size += SizeField(num) + protowire.SizeTag(FieldMessage) + n
+ }
+ return size
+}
+
+// AppendUnknown appends unknown fields to b in MessageSet format.
+//
+// For historic reasons, unresolved items in a MessageSet are stored in a
+// message's unknown fields section in non-MessageSet format. That is, an
+// unknown item with typeID T and value V appears in the unknown fields as
+// a field with number T and value V.
+//
+// This function converts the unknown fields back into MessageSet form.
+func AppendUnknown(b, unknown []byte) ([]byte, error) {
+ for len(unknown) > 0 {
+ num, typ, n := protowire.ConsumeTag(unknown)
+ if n < 0 || typ != protowire.BytesType {
+ return nil, errors.New("invalid data in message set unknown fields")
+ }
+ unknown = unknown[n:]
+ _, n = protowire.ConsumeBytes(unknown)
+ if n < 0 {
+ return nil, errors.New("invalid data in message set unknown fields")
+ }
+ b = AppendFieldStart(b, num)
+ b = protowire.AppendTag(b, FieldMessage, protowire.BytesType)
+ b = append(b, unknown[:n]...)
+ b = AppendFieldEnd(b)
+ unknown = unknown[n:]
+ }
+ return b, nil
+}