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Diffstat (limited to 'vendor/github.com/golang/protobuf/proto/buffer.go')
-rw-r--r-- | vendor/github.com/golang/protobuf/proto/buffer.go | 324 |
1 files changed, 324 insertions, 0 deletions
diff --git a/vendor/github.com/golang/protobuf/proto/buffer.go b/vendor/github.com/golang/protobuf/proto/buffer.go new file mode 100644 index 00000000..e810e6fe --- /dev/null +++ b/vendor/github.com/golang/protobuf/proto/buffer.go @@ -0,0 +1,324 @@ +// 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 proto + +import ( + "errors" + "fmt" + + "google.golang.org/protobuf/encoding/prototext" + "google.golang.org/protobuf/encoding/protowire" + "google.golang.org/protobuf/runtime/protoimpl" +) + +const ( + WireVarint = 0 + WireFixed32 = 5 + WireFixed64 = 1 + WireBytes = 2 + WireStartGroup = 3 + WireEndGroup = 4 +) + +// EncodeVarint returns the varint encoded bytes of v. +func EncodeVarint(v uint64) []byte { + return protowire.AppendVarint(nil, v) +} + +// SizeVarint returns the length of the varint encoded bytes of v. +// This is equal to len(EncodeVarint(v)). +func SizeVarint(v uint64) int { + return protowire.SizeVarint(v) +} + +// DecodeVarint parses a varint encoded integer from b, +// returning the integer value and the length of the varint. +// It returns (0, 0) if there is a parse error. +func DecodeVarint(b []byte) (uint64, int) { + v, n := protowire.ConsumeVarint(b) + if n < 0 { + return 0, 0 + } + return v, n +} + +// Buffer is a buffer for encoding and decoding the protobuf wire format. +// It may be reused between invocations to reduce memory usage. +type Buffer struct { + buf []byte + idx int + deterministic bool +} + +// NewBuffer allocates a new Buffer initialized with buf, +// where the contents of buf are considered the unread portion of the buffer. +func NewBuffer(buf []byte) *Buffer { + return &Buffer{buf: buf} +} + +// SetDeterministic specifies whether to use deterministic serialization. +// +// Deterministic serialization guarantees that for a given binary, equal +// messages will always be serialized to the same bytes. This implies: +// +// - Repeated serialization of a message will return the same bytes. +// - Different processes of the same binary (which may be executing on +// different machines) will serialize equal messages to the same bytes. +// +// Note that the deterministic serialization is NOT canonical across +// languages. It is not guaranteed to remain stable over time. It is unstable +// across different builds with schema changes due to unknown fields. +// Users who need canonical serialization (e.g., persistent storage in a +// canonical form, fingerprinting, etc.) should define their own +// canonicalization specification and implement their own serializer rather +// than relying on this API. +// +// If deterministic serialization is requested, map entries will be sorted +// by keys in lexographical order. This is an implementation detail and +// subject to change. +func (b *Buffer) SetDeterministic(deterministic bool) { + b.deterministic = deterministic +} + +// SetBuf sets buf as the internal buffer, +// where the contents of buf are considered the unread portion of the buffer. +func (b *Buffer) SetBuf(buf []byte) { + b.buf = buf + b.idx = 0 +} + +// Reset clears the internal buffer of all written and unread data. +func (b *Buffer) Reset() { + b.buf = b.buf[:0] + b.idx = 0 +} + +// Bytes returns the internal buffer. +func (b *Buffer) Bytes() []byte { + return b.buf +} + +// Unread returns the unread portion of the buffer. +func (b *Buffer) Unread() []byte { + return b.buf[b.idx:] +} + +// Marshal appends the wire-format encoding of m to the buffer. +func (b *Buffer) Marshal(m Message) error { + var err error + b.buf, err = marshalAppend(b.buf, m, b.deterministic) + return err +} + +// Unmarshal parses the wire-format message in the buffer and +// places the decoded results in m. +// It does not reset m before unmarshaling. +func (b *Buffer) Unmarshal(m Message) error { + err := UnmarshalMerge(b.Unread(), m) + b.idx = len(b.buf) + return err +} + +type unknownFields struct{ XXX_unrecognized protoimpl.UnknownFields } + +func (m *unknownFields) String() string { panic("not implemented") } +func (m *unknownFields) Reset() { panic("not implemented") } +func (m *unknownFields) ProtoMessage() { panic("not implemented") } + +// DebugPrint dumps the encoded bytes of b with a header and footer including s +// to stdout. This is only intended for debugging. +func (*Buffer) DebugPrint(s string, b []byte) { + m := MessageReflect(new(unknownFields)) + m.SetUnknown(b) + b, _ = prototext.MarshalOptions{AllowPartial: true, Indent: "\t"}.Marshal(m.Interface()) + fmt.Printf("==== %s ====\n%s==== %s ====\n", s, b, s) +} + +// EncodeVarint appends an unsigned varint encoding to the buffer. +func (b *Buffer) EncodeVarint(v uint64) error { + b.buf = protowire.AppendVarint(b.buf, v) + return nil +} + +// EncodeZigzag32 appends a 32-bit zig-zag varint encoding to the buffer. +func (b *Buffer) EncodeZigzag32(v uint64) error { + return b.EncodeVarint(uint64((uint32(v) << 1) ^ uint32((int32(v) >> 31)))) +} + +// EncodeZigzag64 appends a 64-bit zig-zag varint encoding to the buffer. +func (b *Buffer) EncodeZigzag64(v uint64) error { + return b.EncodeVarint(uint64((uint64(v) << 1) ^ uint64((int64(v) >> 63)))) +} + +// EncodeFixed32 appends a 32-bit little-endian integer to the buffer. +func (b *Buffer) EncodeFixed32(v uint64) error { + b.buf = protowire.AppendFixed32(b.buf, uint32(v)) + return nil +} + +// EncodeFixed64 appends a 64-bit little-endian integer to the buffer. +func (b *Buffer) EncodeFixed64(v uint64) error { + b.buf = protowire.AppendFixed64(b.buf, uint64(v)) + return nil +} + +// EncodeRawBytes appends a length-prefixed raw bytes to the buffer. +func (b *Buffer) EncodeRawBytes(v []byte) error { + b.buf = protowire.AppendBytes(b.buf, v) + return nil +} + +// EncodeStringBytes appends a length-prefixed raw bytes to the buffer. +// It does not validate whether v contains valid UTF-8. +func (b *Buffer) EncodeStringBytes(v string) error { + b.buf = protowire.AppendString(b.buf, v) + return nil +} + +// EncodeMessage appends a length-prefixed encoded message to the buffer. +func (b *Buffer) EncodeMessage(m Message) error { + var err error + b.buf = protowire.AppendVarint(b.buf, uint64(Size(m))) + b.buf, err = marshalAppend(b.buf, m, b.deterministic) + return err +} + +// DecodeVarint consumes an encoded unsigned varint from the buffer. +func (b *Buffer) DecodeVarint() (uint64, error) { + v, n := protowire.ConsumeVarint(b.buf[b.idx:]) + if n < 0 { + return 0, protowire.ParseError(n) + } + b.idx += n + return uint64(v), nil +} + +// DecodeZigzag32 consumes an encoded 32-bit zig-zag varint from the buffer. +func (b *Buffer) DecodeZigzag32() (uint64, error) { + v, err := b.DecodeVarint() + if err != nil { + return 0, err + } + return uint64((uint32(v) >> 1) ^ uint32((int32(v&1)<<31)>>31)), nil +} + +// DecodeZigzag64 consumes an encoded 64-bit zig-zag varint from the buffer. +func (b *Buffer) DecodeZigzag64() (uint64, error) { + v, err := b.DecodeVarint() + if err != nil { + return 0, err + } + return uint64((uint64(v) >> 1) ^ uint64((int64(v&1)<<63)>>63)), nil +} + +// DecodeFixed32 consumes a 32-bit little-endian integer from the buffer. +func (b *Buffer) DecodeFixed32() (uint64, error) { + v, n := protowire.ConsumeFixed32(b.buf[b.idx:]) + if n < 0 { + return 0, protowire.ParseError(n) + } + b.idx += n + return uint64(v), nil +} + +// DecodeFixed64 consumes a 64-bit little-endian integer from the buffer. +func (b *Buffer) DecodeFixed64() (uint64, error) { + v, n := protowire.ConsumeFixed64(b.buf[b.idx:]) + if n < 0 { + return 0, protowire.ParseError(n) + } + b.idx += n + return uint64(v), nil +} + +// DecodeRawBytes consumes a length-prefixed raw bytes from the buffer. +// If alloc is specified, it returns a copy the raw bytes +// rather than a sub-slice of the buffer. +func (b *Buffer) DecodeRawBytes(alloc bool) ([]byte, error) { + v, n := protowire.ConsumeBytes(b.buf[b.idx:]) + if n < 0 { + return nil, protowire.ParseError(n) + } + b.idx += n + if alloc { + v = append([]byte(nil), v...) + } + return v, nil +} + +// DecodeStringBytes consumes a length-prefixed raw bytes from the buffer. +// It does not validate whether the raw bytes contain valid UTF-8. +func (b *Buffer) DecodeStringBytes() (string, error) { + v, n := protowire.ConsumeString(b.buf[b.idx:]) + if n < 0 { + return "", protowire.ParseError(n) + } + b.idx += n + return v, nil +} + +// DecodeMessage consumes a length-prefixed message from the buffer. +// It does not reset m before unmarshaling. +func (b *Buffer) DecodeMessage(m Message) error { + v, err := b.DecodeRawBytes(false) + if err != nil { + return err + } + return UnmarshalMerge(v, m) +} + +// DecodeGroup consumes a message group from the buffer. +// It assumes that the start group marker has already been consumed and +// consumes all bytes until (and including the end group marker). +// It does not reset m before unmarshaling. +func (b *Buffer) DecodeGroup(m Message) error { + v, n, err := consumeGroup(b.buf[b.idx:]) + if err != nil { + return err + } + b.idx += n + return UnmarshalMerge(v, m) +} + +// consumeGroup parses b until it finds an end group marker, returning +// the raw bytes of the message (excluding the end group marker) and the +// the total length of the message (including the end group marker). +func consumeGroup(b []byte) ([]byte, int, error) { + b0 := b + depth := 1 // assume this follows a start group marker + for { + _, wtyp, tagLen := protowire.ConsumeTag(b) + if tagLen < 0 { + return nil, 0, protowire.ParseError(tagLen) + } + b = b[tagLen:] + + var valLen int + switch wtyp { + case protowire.VarintType: + _, valLen = protowire.ConsumeVarint(b) + case protowire.Fixed32Type: + _, valLen = protowire.ConsumeFixed32(b) + case protowire.Fixed64Type: + _, valLen = protowire.ConsumeFixed64(b) + case protowire.BytesType: + _, valLen = protowire.ConsumeBytes(b) + case protowire.StartGroupType: + depth++ + case protowire.EndGroupType: + depth-- + default: + return nil, 0, errors.New("proto: cannot parse reserved wire type") + } + if valLen < 0 { + return nil, 0, protowire.ParseError(valLen) + } + b = b[valLen:] + + if depth == 0 { + return b0[:len(b0)-len(b)-tagLen], len(b0) - len(b), nil + } + } +} |