versions/v1_4_0/mynewt-newtmgr/vendor/github.com/ugorji/go/codec/helper_unsafe.go

// +build unsafe

// Copyright (c) 2012-2015 Ugorji Nwoke. All rights reserved.
// Use of this source code is governed by a MIT license found in the LICENSE file.

package codec

import (
	"runtime"
	"unsafe"
)

// This file has unsafe variants of some helper methods.
// NOTE: See helper_not_unsafe.go for the usage information.

type unsafeString struct {
	Data uintptr
	Len  int
}

type unsafeSlice struct {
	Data uintptr
	Len  int
	Cap  int
}

func stringView(v []byte) string {
	if len(v) == 0 {
		return ""
	}

	bx := (*unsafeSlice)(unsafe.Pointer(&v))
	sx := unsafeString{bx.Data, bx.Len}
	return *(*string)(unsafe.Pointer(&sx))
}

func bytesView(v string) []byte {
	if len(v) == 0 {
		return zeroByteSlice
	}

	sx := (*unsafeString)(unsafe.Pointer(&v))
	bx := unsafeSlice{sx.Data, sx.Len, sx.Len}
	return *(*[]byte)(unsafe.Pointer(&bx))
}

func keepAlive4BytesView(v string) {
	runtime.KeepAlive(v)
}

func keepAlive4StringView(v []byte) {
	runtime.KeepAlive(v)
}