// Copyright 2021 ByteDance Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package hack

import (
	"reflect"
	"unsafe"
)

// StringToBytes converts a string to a byte slice.
//
// This is a shallow copy, means that the returned byte slice reuse
// the underlying array in string, so you can't change the returned
// byte slice in any situations.
func StringToBytes(s string) (b []byte) {
	bh := (*reflect.SliceHeader)(unsafe.Pointer(&b))
	sh := (*reflect.StringHeader)(unsafe.Pointer(&s))
	bh.Data = sh.Data
	bh.Len = sh.Len
	bh.Cap = sh.Len
	return b
}

// BytesToString converts a byte slice to a string.
//
// This is a shallow copy, means that the returned string reuse the
// underlying array in byte slice, it's your responsibility to keep
// the input byte slice survive until you don't access the string anymore.
func BytesToString(b []byte) string {
	return *(*string)(unsafe.Pointer(&b))
}