podman

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// Copyright 2019 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// Package filedesc provides functionality for constructing descriptors.
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//
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// The types in this package implement interfaces in the protoreflect package
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// related to protobuf descripriptors.
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package filedesc
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import (
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	"google.golang.org/protobuf/encoding/protowire"
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	"google.golang.org/protobuf/internal/genid"
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	"google.golang.org/protobuf/reflect/protoreflect"
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	"google.golang.org/protobuf/reflect/protoregistry"
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)
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// Builder construct a protoreflect.FileDescriptor from the raw descriptor.
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type Builder struct {
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	// GoPackagePath is the Go package path that is invoking this builder.
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	GoPackagePath string
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	// RawDescriptor is the wire-encoded bytes of FileDescriptorProto
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	// and must be populated.
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	RawDescriptor []byte
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	// NumEnums is the total number of enums declared in the file.
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	NumEnums int32
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	// NumMessages is the total number of messages declared in the file.
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	// It includes the implicit message declarations for map entries.
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	NumMessages int32
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	// NumExtensions is the total number of extensions declared in the file.
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	NumExtensions int32
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	// NumServices is the total number of services declared in the file.
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	NumServices int32
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	// TypeResolver resolves extension field types for descriptor options.
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	// If nil, it uses protoregistry.GlobalTypes.
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	TypeResolver interface {
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		protoregistry.ExtensionTypeResolver
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	}
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	// FileRegistry is use to lookup file, enum, and message dependencies.
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	// Once constructed, the file descriptor is registered here.
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	// If nil, it uses protoregistry.GlobalFiles.
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	FileRegistry interface {
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		FindFileByPath(string) (protoreflect.FileDescriptor, error)
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		FindDescriptorByName(protoreflect.FullName) (protoreflect.Descriptor, error)
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		RegisterFile(protoreflect.FileDescriptor) error
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	}
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}
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// resolverByIndex is an interface Builder.FileRegistry may implement.
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// If so, it permits looking up an enum or message dependency based on the
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// sub-list and element index into filetype.Builder.DependencyIndexes.
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type resolverByIndex interface {
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	FindEnumByIndex(int32, int32, []Enum, []Message) protoreflect.EnumDescriptor
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	FindMessageByIndex(int32, int32, []Enum, []Message) protoreflect.MessageDescriptor
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}
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// Indexes of each sub-list in filetype.Builder.DependencyIndexes.
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const (
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	listFieldDeps int32 = iota
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	listExtTargets
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	listExtDeps
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	listMethInDeps
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	listMethOutDeps
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)
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// Out is the output of the Builder.
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type Out struct {
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	File protoreflect.FileDescriptor
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	// Enums is all enum descriptors in "flattened ordering".
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	Enums []Enum
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	// Messages is all message descriptors in "flattened ordering".
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	// It includes the implicit message declarations for map entries.
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	Messages []Message
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	// Extensions is all extension descriptors in "flattened ordering".
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	Extensions []Extension
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	// Service is all service descriptors in "flattened ordering".
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	Services []Service
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}
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// Build constructs a FileDescriptor given the parameters set in Builder.
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// It assumes that the inputs are well-formed and panics if any inconsistencies
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// are encountered.
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//
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// If NumEnums+NumMessages+NumExtensions+NumServices is zero,
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// then Build automatically derives them from the raw descriptor.
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func (db Builder) Build() (out Out) {
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	// Populate the counts if uninitialized.
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	if db.NumEnums+db.NumMessages+db.NumExtensions+db.NumServices == 0 {
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		db.unmarshalCounts(db.RawDescriptor, true)
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	}
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	// Initialize resolvers and registries if unpopulated.
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	if db.TypeResolver == nil {
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		db.TypeResolver = protoregistry.GlobalTypes
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	}
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	if db.FileRegistry == nil {
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		db.FileRegistry = protoregistry.GlobalFiles
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	}
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	fd := newRawFile(db)
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	out.File = fd
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	out.Enums = fd.allEnums
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	out.Messages = fd.allMessages
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	out.Extensions = fd.allExtensions
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	out.Services = fd.allServices
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	if err := db.FileRegistry.RegisterFile(fd); err != nil {
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		panic(err)
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	}
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	return out
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}
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// unmarshalCounts counts the number of enum, message, extension, and service
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// declarations in the raw message, which is either a FileDescriptorProto
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// or a MessageDescriptorProto depending on whether isFile is set.
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func (db *Builder) unmarshalCounts(b []byte, isFile bool) {
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	for len(b) > 0 {
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		num, typ, n := protowire.ConsumeTag(b)
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		b = b[n:]
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		switch typ {
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		case protowire.BytesType:
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			v, m := protowire.ConsumeBytes(b)
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			b = b[m:]
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			if isFile {
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				switch num {
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				case genid.FileDescriptorProto_EnumType_field_number:
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					db.NumEnums++
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				case genid.FileDescriptorProto_MessageType_field_number:
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					db.unmarshalCounts(v, false)
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					db.NumMessages++
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				case genid.FileDescriptorProto_Extension_field_number:
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					db.NumExtensions++
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				case genid.FileDescriptorProto_Service_field_number:
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					db.NumServices++
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				}
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			} else {
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				switch num {
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				case genid.DescriptorProto_EnumType_field_number:
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					db.NumEnums++
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				case genid.DescriptorProto_NestedType_field_number:
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					db.unmarshalCounts(v, false)
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					db.NumMessages++
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				case genid.DescriptorProto_Extension_field_number:
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					db.NumExtensions++
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				}
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			}
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		default:
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			m := protowire.ConsumeFieldValue(num, typ, b)
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			b = b[m:]
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		}
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	}
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}
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