github.com/bingoohuang/gg@v0.0.0-20240325092523-45da7dee9335/pkg/sqlparse/tidbparser/dependency/util/hack/hack.go (about)

     1  // Copyright 2015 PingCAP, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // See the License for the specific language governing permissions and
    12  // limitations under the License.
    13  
    14  package hack
    15  
    16  import (
    17  	"reflect"
    18  	"unsafe"
    19  )
    20  
    21  // String converts slice to string without copy.
    22  // Use at your own risk.
    23  func String(b []byte) (s string) {
    24  	if len(b) == 0 {
    25  		return ""
    26  	}
    27  	pbytes := (*reflect.SliceHeader)(unsafe.Pointer(&b))
    28  	pstring := (*reflect.StringHeader)(unsafe.Pointer(&s))
    29  	pstring.Data = pbytes.Data
    30  	pstring.Len = pbytes.Len
    31  	return
    32  }
    33  
    34  // Slice converts string to slice without copy.
    35  // Use at your own risk.
    36  func Slice(s string) (b []byte) {
    37  	pbytes := (*reflect.SliceHeader)(unsafe.Pointer(&b))
    38  	pstring := (*reflect.StringHeader)(unsafe.Pointer(&s))
    39  	pbytes.Data = pstring.Data
    40  	pbytes.Len = pstring.Len
    41  	pbytes.Cap = pstring.Len
    42  	return
    43  }