podman

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// Go support for Protocol Buffers - Google's data interchange format
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//
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// Copyright 2012 The Go Authors.  All rights reserved.
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// https://github.com/golang/protobuf
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//
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// Redistribution and use in source and binary forms, with or without
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// modification, are permitted provided that the following conditions are
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// met:
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//
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//     * Redistributions of source code must retain the above copyright
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// notice, this list of conditions and the following disclaimer.
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//     * Redistributions in binary form must reproduce the above
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// copyright notice, this list of conditions and the following disclaimer
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// in the documentation and/or other materials provided with the
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// distribution.
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//     * Neither the name of Google Inc. nor the names of its
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// contributors may be used to endorse or promote products derived from
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// this software without specific prior written permission.
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//
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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// +build !purego,!appengine,!js
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// This file contains the implementation of the proto field accesses using package unsafe.
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package proto
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import (
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	"reflect"
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	"sync/atomic"
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	"unsafe"
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)
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const unsafeAllowed = true
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// A field identifies a field in a struct, accessible from a pointer.
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// In this implementation, a field is identified by its byte offset from the start of the struct.
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type field uintptr
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// toField returns a field equivalent to the given reflect field.
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func toField(f *reflect.StructField) field {
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	return field(f.Offset)
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}
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// invalidField is an invalid field identifier.
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const invalidField = ^field(0)
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// zeroField is a noop when calling pointer.offset.
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const zeroField = field(0)
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// IsValid reports whether the field identifier is valid.
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func (f field) IsValid() bool {
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	return f != invalidField
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}
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// The pointer type below is for the new table-driven encoder/decoder.
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// The implementation here uses unsafe.Pointer to create a generic pointer.
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// In pointer_reflect.go we use reflect instead of unsafe to implement
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// the same (but slower) interface.
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type pointer struct {
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	p unsafe.Pointer
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}
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// size of pointer
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var ptrSize = unsafe.Sizeof(uintptr(0))
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// toPointer converts an interface of pointer type to a pointer
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// that points to the same target.
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func toPointer(i *Message) pointer {
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	// Super-tricky - read pointer out of data word of interface value.
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	// Saves ~25ns over the equivalent:
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	// return valToPointer(reflect.ValueOf(*i))
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	return pointer{p: (*[2]unsafe.Pointer)(unsafe.Pointer(i))[1]}
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}
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// toAddrPointer converts an interface to a pointer that points to
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// the interface data.
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func toAddrPointer(i *interface{}, isptr bool) pointer {
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	// Super-tricky - read or get the address of data word of interface value.
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	if isptr {
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		// The interface is of pointer type, thus it is a direct interface.
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		// The data word is the pointer data itself. We take its address.
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		return pointer{p: unsafe.Pointer(uintptr(unsafe.Pointer(i)) + ptrSize)}
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	}
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	// The interface is not of pointer type. The data word is the pointer
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	// to the data.
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	return pointer{p: (*[2]unsafe.Pointer)(unsafe.Pointer(i))[1]}
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}
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// valToPointer converts v to a pointer. v must be of pointer type.
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func valToPointer(v reflect.Value) pointer {
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	return pointer{p: unsafe.Pointer(v.Pointer())}
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}
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// offset converts from a pointer to a structure to a pointer to
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// one of its fields.
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func (p pointer) offset(f field) pointer {
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	// For safety, we should panic if !f.IsValid, however calling panic causes
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	// this to no longer be inlineable, which is a serious performance cost.
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	/*
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		if !f.IsValid() {
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			panic("invalid field")
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		}
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	*/
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	return pointer{p: unsafe.Pointer(uintptr(p.p) + uintptr(f))}
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}
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func (p pointer) isNil() bool {
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	return p.p == nil
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}
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func (p pointer) toInt64() *int64 {
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	return (*int64)(p.p)
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}
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func (p pointer) toInt64Ptr() **int64 {
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	return (**int64)(p.p)
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}
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func (p pointer) toInt64Slice() *[]int64 {
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	return (*[]int64)(p.p)
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}
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func (p pointer) toInt32() *int32 {
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	return (*int32)(p.p)
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}
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// See pointer_reflect.go for why toInt32Ptr/Slice doesn't exist.
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/*
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	func (p pointer) toInt32Ptr() **int32 {
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		return (**int32)(p.p)
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	}
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	func (p pointer) toInt32Slice() *[]int32 {
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		return (*[]int32)(p.p)
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	}
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*/
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func (p pointer) getInt32Ptr() *int32 {
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	return *(**int32)(p.p)
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}
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func (p pointer) setInt32Ptr(v int32) {
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	*(**int32)(p.p) = &v
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}
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// getInt32Slice loads a []int32 from p.
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// The value returned is aliased with the original slice.
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// This behavior differs from the implementation in pointer_reflect.go.
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func (p pointer) getInt32Slice() []int32 {
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	return *(*[]int32)(p.p)
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}
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// setInt32Slice stores a []int32 to p.
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// The value set is aliased with the input slice.
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// This behavior differs from the implementation in pointer_reflect.go.
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func (p pointer) setInt32Slice(v []int32) {
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	*(*[]int32)(p.p) = v
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}
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// TODO: Can we get rid of appendInt32Slice and use setInt32Slice instead?
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func (p pointer) appendInt32Slice(v int32) {
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	s := (*[]int32)(p.p)
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	*s = append(*s, v)
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}
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func (p pointer) toUint64() *uint64 {
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	return (*uint64)(p.p)
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}
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func (p pointer) toUint64Ptr() **uint64 {
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	return (**uint64)(p.p)
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}
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func (p pointer) toUint64Slice() *[]uint64 {
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	return (*[]uint64)(p.p)
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}
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func (p pointer) toUint32() *uint32 {
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	return (*uint32)(p.p)
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}
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func (p pointer) toUint32Ptr() **uint32 {
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	return (**uint32)(p.p)
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}
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func (p pointer) toUint32Slice() *[]uint32 {
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	return (*[]uint32)(p.p)
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}
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func (p pointer) toBool() *bool {
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	return (*bool)(p.p)
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}
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func (p pointer) toBoolPtr() **bool {
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	return (**bool)(p.p)
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}
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func (p pointer) toBoolSlice() *[]bool {
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	return (*[]bool)(p.p)
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}
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func (p pointer) toFloat64() *float64 {
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	return (*float64)(p.p)
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}
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func (p pointer) toFloat64Ptr() **float64 {
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	return (**float64)(p.p)
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}
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func (p pointer) toFloat64Slice() *[]float64 {
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	return (*[]float64)(p.p)
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}
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func (p pointer) toFloat32() *float32 {
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	return (*float32)(p.p)
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}
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func (p pointer) toFloat32Ptr() **float32 {
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	return (**float32)(p.p)
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}
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func (p pointer) toFloat32Slice() *[]float32 {
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	return (*[]float32)(p.p)
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}
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func (p pointer) toString() *string {
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	return (*string)(p.p)
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}
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func (p pointer) toStringPtr() **string {
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	return (**string)(p.p)
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}
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func (p pointer) toStringSlice() *[]string {
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	return (*[]string)(p.p)
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}
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func (p pointer) toBytes() *[]byte {
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	return (*[]byte)(p.p)
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}
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func (p pointer) toBytesSlice() *[][]byte {
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	return (*[][]byte)(p.p)
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}
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func (p pointer) toExtensions() *XXX_InternalExtensions {
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	return (*XXX_InternalExtensions)(p.p)
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}
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func (p pointer) toOldExtensions() *map[int32]Extension {
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	return (*map[int32]Extension)(p.p)
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}
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// getPointerSlice loads []*T from p as a []pointer.
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// The value returned is aliased with the original slice.
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// This behavior differs from the implementation in pointer_reflect.go.
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func (p pointer) getPointerSlice() []pointer {
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	// Super-tricky - p should point to a []*T where T is a
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	// message type. We load it as []pointer.
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	return *(*[]pointer)(p.p)
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}
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// setPointerSlice stores []pointer into p as a []*T.
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// The value set is aliased with the input slice.
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// This behavior differs from the implementation in pointer_reflect.go.
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func (p pointer) setPointerSlice(v []pointer) {
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	// Super-tricky - p should point to a []*T where T is a
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	// message type. We store it as []pointer.
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	*(*[]pointer)(p.p) = v
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}
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// getPointer loads the pointer at p and returns it.
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func (p pointer) getPointer() pointer {
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	return pointer{p: *(*unsafe.Pointer)(p.p)}
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}
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// setPointer stores the pointer q at p.
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func (p pointer) setPointer(q pointer) {
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	*(*unsafe.Pointer)(p.p) = q.p
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}
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// append q to the slice pointed to by p.
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func (p pointer) appendPointer(q pointer) {
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	s := (*[]unsafe.Pointer)(p.p)
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	*s = append(*s, q.p)
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}
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// getInterfacePointer returns a pointer that points to the
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// interface data of the interface pointed by p.
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func (p pointer) getInterfacePointer() pointer {
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	// Super-tricky - read pointer out of data word of interface value.
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	return pointer{p: (*(*[2]unsafe.Pointer)(p.p))[1]}
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}
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// asPointerTo returns a reflect.Value that is a pointer to an
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// object of type t stored at p.
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func (p pointer) asPointerTo(t reflect.Type) reflect.Value {
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	return reflect.NewAt(t, p.p)
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}
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func atomicLoadUnmarshalInfo(p **unmarshalInfo) *unmarshalInfo {
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	return (*unmarshalInfo)(atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(p))))
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}
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func atomicStoreUnmarshalInfo(p **unmarshalInfo, v *unmarshalInfo) {
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	atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(p)), unsafe.Pointer(v))
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}
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func atomicLoadMarshalInfo(p **marshalInfo) *marshalInfo {
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	return (*marshalInfo)(atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(p))))
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}
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func atomicStoreMarshalInfo(p **marshalInfo, v *marshalInfo) {
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	atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(p)), unsafe.Pointer(v))
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}
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func atomicLoadMergeInfo(p **mergeInfo) *mergeInfo {
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	return (*mergeInfo)(atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(p))))
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}
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func atomicStoreMergeInfo(p **mergeInfo, v *mergeInfo) {
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	atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(p)), unsafe.Pointer(v))
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}
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func atomicLoadDiscardInfo(p **discardInfo) *discardInfo {
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	return (*discardInfo)(atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(p))))
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}
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func atomicStoreDiscardInfo(p **discardInfo, v *discardInfo) {
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	atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(p)), unsafe.Pointer(v))
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}
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