pointer_unsafe.go 911 Bytes
Newer Older
ale's avatar
ale committed
1
2
// Copyright 2018, The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
3
// license that can be found in the LICENSE file.
ale's avatar
ale committed
4

5
//go:build !purego
ale's avatar
ale committed
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
// +build !purego

package value

import (
	"reflect"
	"unsafe"
)

// Pointer is an opaque typed pointer and is guaranteed to be comparable.
type Pointer struct {
	p unsafe.Pointer
	t reflect.Type
}

// PointerOf returns a Pointer from v, which must be a
// reflect.Ptr, reflect.Slice, or reflect.Map.
func PointerOf(v reflect.Value) Pointer {
	// The proper representation of a pointer is unsafe.Pointer,
	// which is necessary if the GC ever uses a moving collector.
	return Pointer{unsafe.Pointer(v.Pointer()), v.Type()}
}
28
29
30
31
32
33
34
35
36
37

// IsNil reports whether the pointer is nil.
func (p Pointer) IsNil() bool {
	return p.p == nil
}

// Uintptr returns the pointer as a uintptr.
func (p Pointer) Uintptr() uintptr {
	return uintptr(p.p)
}