// Unsafe string↔[]byte conversion library
// Copyright (c) 2017 by Michał Nazarewicz <mina86@mina86.com>
//
// 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 unsafeConvert provides functions for unsafely convert between
// a string and a slice of bytes.  You probably shouldn’t use it unless you need
// to squeeze extra performance from your performance-critical code path.
package unsafeConvert

import (
	"reflect"
	"unsafe"
)

// String converts a slice of bytes into a string without performing a copy.
// NOTE: This is an unsafe operation and may lead to problems if the bytes
// passed as argument are changed while the string is used.  No checking whether
// bytes are valid UTF-8 data is performed.
func String(bytes []byte) string {
	hdr := *(*reflect.SliceHeader)(unsafe.Pointer(&bytes))
	return *(*string)(unsafe.Pointer(&reflect.StringHeader{
		Data: hdr.Data,
		Len:  hdr.Len,
	}))
}

// Bytes converts a string into a slice of bytes without performing a copy.
// NOTE: This is an unsafe operation and may lead to problems if the bytes are
// changed.
func Bytes(str string) []byte {
	hdr := *(*reflect.StringHeader)(unsafe.Pointer(&str))
	return *(*[]byte)(unsafe.Pointer(&reflect.SliceHeader{
		Data: hdr.Data,
		Len:  hdr.Len,
		Cap:  hdr.Len,
	}))
}

// Following added for libsimpleio by Philip Munts on 25 October 2020
func Ptr(str string) *byte {
  return &Bytes(str)[0]
}