Damien Neil 61781dd92f all: abstract fast-path marshal and unmarshal inputs and outputs
We may want to make changes to the inputs and outputs of the fast-path
functions in the future. For example, we likely want to add the ability
for the fast-path unmarshal to report back whether the unmarshaled
message is known to be initialized.

Change the signatures of these functions to take in and return struct
types which can be extended with whatever fields we want in the future.

Change-Id: Idead360785df730283a4630ea405265b72482e62
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/215719
Reviewed-by: Joe Tsai <joetsai@google.com>
2020-01-22 00:22:46 +00:00

106 lines
3.3 KiB
Go

// 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 protoiface contains types referenced or implemented by messages.
//
// WARNING: This package should only be imported by message implementations.
// The functionality found in this package should be accessed through
// higher-level abstractions provided by the proto package.
package protoiface
import (
"google.golang.org/protobuf/internal/pragma"
"google.golang.org/protobuf/reflect/protoreflect"
)
// Methods is a set of optional fast-path implementations of various operations.
type Methods = struct {
pragma.NoUnkeyedLiterals
// Flags indicate support for optional features.
Flags SupportFlags
// Size returns the size in bytes of the wire-format encoding of m.
// MarshalAppend must be provided if a custom Size is provided.
Size func(m protoreflect.Message, opts MarshalOptions) int
// Marshal writes the wire-format encoding of m to the provided buffer.
// Size should be provided if a custom MarshalAppend is provided.
// It must not perform required field checks.
Marshal func(m protoreflect.Message, in MarshalInput) (MarshalOutput, error)
// Unmarshal parses the wire-format encoding of a message and merges the result to m.
// It must not reset m or perform required field checks.
Unmarshal func(m protoreflect.Message, in UnmarshalInput) (UnmarshalOutput, error)
// IsInitialized returns an error if any required fields in m are not set.
IsInitialized func(m protoreflect.Message) error
}
type SupportFlags = uint64
const (
// SupportMarshalDeterministic reports whether MarshalOptions.Deterministic is supported.
SupportMarshalDeterministic SupportFlags = 1 << iota
// SupportUnmarshalDiscardUnknown reports whether UnmarshalOptions.DiscardUnknown is supported.
SupportUnmarshalDiscardUnknown
)
// MarshalInput is input to the marshaler.
type MarshalInput = struct {
pragma.NoUnkeyedLiterals
Buf []byte // output is appended to this buffer
Options MarshalOptions
}
// MarshalOutput is output from the marshaler.
type MarshalOutput = struct {
pragma.NoUnkeyedLiterals
Buf []byte // contains marshaled message
}
// MarshalOptions configure the marshaler.
//
// This type is identical to the one in package proto.
type MarshalOptions = struct {
pragma.NoUnkeyedLiterals
AllowPartial bool // must be treated as true by method implementations
Deterministic bool
UseCachedSize bool
}
// UnmarshalInput is input to the unmarshaler.
type UnmarshalInput = struct {
pragma.NoUnkeyedLiterals
Buf []byte // input buffer
Options UnmarshalOptions
}
// UnmarshalOutput is output from the unmarshaler.
type UnmarshalOutput = struct {
pragma.NoUnkeyedLiterals
// Contents available for future expansion.
}
// UnmarshalOptions configures the unmarshaler.
//
// This type is identical to the one in package proto.
type UnmarshalOptions = struct {
pragma.NoUnkeyedLiterals
Merge bool // must be treated as true by method implementations
AllowPartial bool // must be treated as true by method implementations
DiscardUnknown bool
Resolver interface {
FindExtensionByName(field protoreflect.FullName) (protoreflect.ExtensionType, error)
FindExtensionByNumber(message protoreflect.FullName, field protoreflect.FieldNumber) (protoreflect.ExtensionType, error)
}
}