xref: /aosp_15_r20/external/go-cmp/cmp/internal/value/pointer_unsafe.go (revision 88d15eac089d7f20c739ff1001d56b91872b21a1)
1*88d15eacSSasha Smundak// Copyright 2018, The Go Authors. All rights reserved.
2*88d15eacSSasha Smundak// Use of this source code is governed by a BSD-style
3*88d15eacSSasha Smundak// license that can be found in the LICENSE file.
4*88d15eacSSasha Smundak
5*88d15eacSSasha Smundak//go:build !purego
6*88d15eacSSasha Smundak// +build !purego
7*88d15eacSSasha Smundak
8*88d15eacSSasha Smundakpackage value
9*88d15eacSSasha Smundak
10*88d15eacSSasha Smundakimport (
11*88d15eacSSasha Smundak	"reflect"
12*88d15eacSSasha Smundak	"unsafe"
13*88d15eacSSasha Smundak)
14*88d15eacSSasha Smundak
15*88d15eacSSasha Smundak// Pointer is an opaque typed pointer and is guaranteed to be comparable.
16*88d15eacSSasha Smundaktype Pointer struct {
17*88d15eacSSasha Smundak	p unsafe.Pointer
18*88d15eacSSasha Smundak	t reflect.Type
19*88d15eacSSasha Smundak}
20*88d15eacSSasha Smundak
21*88d15eacSSasha Smundak// PointerOf returns a Pointer from v, which must be a
22*88d15eacSSasha Smundak// reflect.Ptr, reflect.Slice, or reflect.Map.
23*88d15eacSSasha Smundakfunc PointerOf(v reflect.Value) Pointer {
24*88d15eacSSasha Smundak	// The proper representation of a pointer is unsafe.Pointer,
25*88d15eacSSasha Smundak	// which is necessary if the GC ever uses a moving collector.
26*88d15eacSSasha Smundak	return Pointer{unsafe.Pointer(v.Pointer()), v.Type()}
27*88d15eacSSasha Smundak}
28*88d15eacSSasha Smundak
29*88d15eacSSasha Smundak// IsNil reports whether the pointer is nil.
30*88d15eacSSasha Smundakfunc (p Pointer) IsNil() bool {
31*88d15eacSSasha Smundak	return p.p == nil
32*88d15eacSSasha Smundak}
33*88d15eacSSasha Smundak
34*88d15eacSSasha Smundak// Uintptr returns the pointer as a uintptr.
35*88d15eacSSasha Smundakfunc (p Pointer) Uintptr() uintptr {
36*88d15eacSSasha Smundak	return uintptr(p.p)
37*88d15eacSSasha Smundak}
38