github.com/Andyfoo/golang/x/sys@v0.0.0-20190901054642-57c1bf301704/windows/env_windows.go (about)

     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  
     7  package windows
     8  
     9  import (
    10  	"syscall"
    11  	"unicode/utf16"
    12  	"unsafe"
    13  )
    14  
    15  func Getenv(key string) (value string, found bool) {
    16  	return syscall.Getenv(key)
    17  }
    18  
    19  func Setenv(key, value string) error {
    20  	return syscall.Setenv(key, value)
    21  }
    22  
    23  func Clearenv() {
    24  	syscall.Clearenv()
    25  }
    26  
    27  func Environ() []string {
    28  	return syscall.Environ()
    29  }
    30  
    31  // Returns a default environment associated with the token, rather than the current
    32  // process. If inheritExisting is true, then this environment also inherits the
    33  // environment of the current process.
    34  func (token Token) Environ(inheritExisting bool) (env []string, err error) {
    35  	var block *uint16
    36  	err = CreateEnvironmentBlock(&block, token, inheritExisting)
    37  	if err != nil {
    38  		return nil, err
    39  	}
    40  	defer DestroyEnvironmentBlock(block)
    41  	blockp := uintptr(unsafe.Pointer(block))
    42  	for {
    43  		entry := (*[(1 << 30) - 1]uint16)(unsafe.Pointer(blockp))[:]
    44  		for i, v := range entry {
    45  			if v == 0 {
    46  				entry = entry[:i]
    47  				break
    48  			}
    49  		}
    50  		if len(entry) == 0 {
    51  			break
    52  		}
    53  		env = append(env, string(utf16.Decode(entry)))
    54  		blockp += 2 * (uintptr(len(entry)) + 1)
    55  	}
    56  	return env, nil
    57  }
    58  
    59  func Unsetenv(key string) error {
    60  	return syscall.Unsetenv(key)
    61  }