encode_unsafe.go raw

   1  // Copyright 2018 The gVisor Authors.
   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  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12  // See the License for the specific language governing permissions and
  13  // limitations under the License.
  14  
  15  package state
  16  
  17  import (
  18  	"reflect"
  19  	"unsafe"
  20  )
  21  
  22  // arrayFromSlice constructs a new pointer to the slice data.
  23  //
  24  // It would be similar to the following:
  25  //
  26  //	x := make([]Foo, l, c)
  27  //	a := ([l]Foo*)(unsafe.Pointer(x[0]))
  28  func arrayFromSlice(obj reflect.Value) reflect.Value {
  29  	return reflect.NewAt(
  30  		reflect.ArrayOf(obj.Cap(), obj.Type().Elem()),
  31  		unsafe.Pointer(obj.Pointer()))
  32  }
  33