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 impl
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import (
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	"reflect"
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	"sync"
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	"sync/atomic"
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	"google.golang.org/protobuf/reflect/protoreflect"
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	"google.golang.org/protobuf/runtime/protoiface"
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)
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// ExtensionInfo implements ExtensionType.
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//
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// This type contains a number of exported fields for legacy compatibility.
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// The only non-deprecated use of this type is through the methods of the
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// ExtensionType interface.
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type ExtensionInfo struct {
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	// An ExtensionInfo may exist in several stages of initialization.
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	//
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	// extensionInfoUninitialized: Some or all of the legacy exported
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	// fields may be set, but none of the unexported fields have been
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	// initialized. This is the starting state for an ExtensionInfo
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	// in legacy generated code.
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	//
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	// extensionInfoDescInit: The desc field is set, but other unexported fields
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	// may not be initialized. Legacy exported fields may or may not be set.
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	// This is the starting state for an ExtensionInfo in newly generated code.
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	//
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	// extensionInfoFullInit: The ExtensionInfo is fully initialized.
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	// This state is only entered after lazy initialization is complete.
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	init uint32
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	mu   sync.Mutex
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	goType reflect.Type
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	desc   extensionTypeDescriptor
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	conv   Converter
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	info   *extensionFieldInfo // for fast-path method implementations
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	// ExtendedType is a typed nil-pointer to the parent message type that
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	// is being extended. It is possible for this to be unpopulated in v2
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	// since the message may no longer implement the MessageV1 interface.
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	//
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	// Deprecated: Use the ExtendedType method instead.
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	ExtendedType protoiface.MessageV1
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	// ExtensionType is the zero value of the extension type.
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	//
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	// For historical reasons, reflect.TypeOf(ExtensionType) and the
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	// type returned by InterfaceOf may not be identical.
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	//
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	// Deprecated: Use InterfaceOf(xt.Zero()) instead.
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	ExtensionType interface{}
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	// Field is the field number of the extension.
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	//
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	// Deprecated: Use the Descriptor().Number method instead.
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	Field int32
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	// Name is the fully qualified name of extension.
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	//
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	// Deprecated: Use the Descriptor().FullName method instead.
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	Name string
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	// Tag is the protobuf struct tag used in the v1 API.
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	//
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	// Deprecated: Do not use.
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	Tag string
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	// Filename is the proto filename in which the extension is defined.
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	//
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	// Deprecated: Use Descriptor().ParentFile().Path() instead.
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	Filename string
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}
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// Stages of initialization: See the ExtensionInfo.init field.
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const (
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	extensionInfoUninitialized = 0
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	extensionInfoDescInit      = 1
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	extensionInfoFullInit      = 2
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)
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func InitExtensionInfo(xi *ExtensionInfo, xd protoreflect.ExtensionDescriptor, goType reflect.Type) {
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	xi.goType = goType
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	xi.desc = extensionTypeDescriptor{xd, xi}
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	xi.init = extensionInfoDescInit
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}
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func (xi *ExtensionInfo) New() protoreflect.Value {
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	return xi.lazyInit().New()
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}
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func (xi *ExtensionInfo) Zero() protoreflect.Value {
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	return xi.lazyInit().Zero()
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}
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func (xi *ExtensionInfo) ValueOf(v interface{}) protoreflect.Value {
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	return xi.lazyInit().PBValueOf(reflect.ValueOf(v))
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}
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func (xi *ExtensionInfo) InterfaceOf(v protoreflect.Value) interface{} {
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	return xi.lazyInit().GoValueOf(v).Interface()
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}
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func (xi *ExtensionInfo) IsValidValue(v protoreflect.Value) bool {
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	return xi.lazyInit().IsValidPB(v)
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}
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func (xi *ExtensionInfo) IsValidInterface(v interface{}) bool {
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	return xi.lazyInit().IsValidGo(reflect.ValueOf(v))
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}
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func (xi *ExtensionInfo) TypeDescriptor() protoreflect.ExtensionTypeDescriptor {
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	if atomic.LoadUint32(&xi.init) < extensionInfoDescInit {
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		xi.lazyInitSlow()
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	}
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	return &xi.desc
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}
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func (xi *ExtensionInfo) lazyInit() Converter {
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	if atomic.LoadUint32(&xi.init) < extensionInfoFullInit {
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		xi.lazyInitSlow()
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	}
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	return xi.conv
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}
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func (xi *ExtensionInfo) lazyInitSlow() {
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	xi.mu.Lock()
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	defer xi.mu.Unlock()
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	if xi.init == extensionInfoFullInit {
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		return
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	}
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	defer atomic.StoreUint32(&xi.init, extensionInfoFullInit)
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	if xi.desc.ExtensionDescriptor == nil {
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		xi.initFromLegacy()
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	}
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	if !xi.desc.ExtensionDescriptor.IsPlaceholder() {
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		if xi.ExtensionType == nil {
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			xi.initToLegacy()
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		}
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		xi.conv = NewConverter(xi.goType, xi.desc.ExtensionDescriptor)
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		xi.info = makeExtensionFieldInfo(xi.desc.ExtensionDescriptor)
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		xi.info.validation = newValidationInfo(xi.desc.ExtensionDescriptor, xi.goType)
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	}
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}
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type extensionTypeDescriptor struct {
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	protoreflect.ExtensionDescriptor
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	xi *ExtensionInfo
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}
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func (xtd *extensionTypeDescriptor) Type() protoreflect.ExtensionType {
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	return xtd.xi
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}
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func (xtd *extensionTypeDescriptor) Descriptor() protoreflect.ExtensionDescriptor {
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	return xtd.ExtensionDescriptor
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}
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