1// Copyright 2010 The Go Authors. All rights reserved.
 2// Use of this source code is governed by a BSD-style
 3// license that can be found in the LICENSE file.
 4
 5// Windows environment variables.
 6
 7package windows
 8
 9import (
10	"syscall"
11	"unsafe"
12)
13
14func Getenv(key string) (value string, found bool) {
15	return syscall.Getenv(key)
16}
17
18func Setenv(key, value string) error {
19	return syscall.Setenv(key, value)
20}
21
22func Clearenv() {
23	syscall.Clearenv()
24}
25
26func Environ() []string {
27	return syscall.Environ()
28}
29
30// Returns a default environment associated with the token, rather than the current
31// process. If inheritExisting is true, then this environment also inherits the
32// environment of the current process.
33func (token Token) Environ(inheritExisting bool) (env []string, err error) {
34	var block *uint16
35	err = CreateEnvironmentBlock(&block, token, inheritExisting)
36	if err != nil {
37		return nil, err
38	}
39	defer DestroyEnvironmentBlock(block)
40	size := unsafe.Sizeof(*block)
41	for *block != 0 {
42		// find NUL terminator
43		end := unsafe.Pointer(block)
44		for *(*uint16)(end) != 0 {
45			end = unsafe.Add(end, size)
46		}
47
48		entry := unsafe.Slice(block, (uintptr(end)-uintptr(unsafe.Pointer(block)))/size)
49		env = append(env, UTF16ToString(entry))
50		block = (*uint16)(unsafe.Add(end, size))
51	}
52	return env, nil
53}
54
55func Unsetenv(key string) error {
56	return syscall.Unsetenv(key)
57}