github.com/qioalice/ekago/v3@v3.3.2-0.20221202205325-5c262d586ee4/ekastr/conversions.go (about)

     1  // The MIT License (MIT)
     2  //
     3  // Copyright (c) 2015-present Aliaksandr Valialkin, VertaMedia, Kirill Danshin,
     4  // Erik Dubbelboer, FastHTTP Authors
     5  //
     6  // Permission is hereby granted, free of charge, to any person obtaining
     7  // a copy of this software and associated documentation files (the "Software"),
     8  // to deal in the Software without restriction,
     9  // including without limitation the rights to use, copy, modify, merge, publish,
    10  // distribute, sublicense, and/or sell copies of the Software
    11  // and to permit persons to whom the Software is furnished to do so,
    12  // subject to the following conditions:
    13  // The above copyright notice and this permission notice shall be included
    14  // in all copies or substantial portions of the Software.
    15  //
    16  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
    17  // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    18  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
    19  // IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
    20  // DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
    21  // ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
    22  // OR OTHER DEALINGS IN THE SOFTWARE.
    23  
    24  package ekastr
    25  
    26  // From:
    27  // https://github.com/valyala/fasthttp/blob/master/bytesconv.go
    28  
    29  import (
    30  	"reflect"
    31  	"unsafe"
    32  )
    33  
    34  /*
    35  B2S converts byte slice to a string without memory allocation.
    36  See https://groups.google.com/forum/#!msg/Golang-Nuts/ENgbUzYvCuU/90yGx7GUAgAJ .
    37  
    38  Note it may break if string and/or slice header will change
    39  in the future go versions.
    40  */
    41  func B2S(b []byte) string {
    42  	/* #nosec G103 */
    43  	return *(*string)(unsafe.Pointer(&b))
    44  }
    45  
    46  /*
    47  S2B converts string to a byte slice without memory allocation.
    48  
    49  Note it may break if string and/or slice header will change
    50  in the future go versions.
    51  */
    52  func S2B(s string) (b []byte) {
    53  	/* #nosec G103 */
    54  	bh := (*reflect.SliceHeader)(unsafe.Pointer(&b))
    55  	/* #nosec G103 */
    56  	sh := *(*reflect.StringHeader)(unsafe.Pointer(&s))
    57  	bh.Data = sh.Data
    58  	bh.Len = sh.Len
    59  	bh.Cap = sh.Len
    60  	return b
    61  }