1// Copyright 2009 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//go:build windows
6
7// Package windows contains an interface to the low-level operating system
8// primitives. OS details vary depending on the underlying system, and
9// by default, godoc will display the OS-specific documentation for the current
10// system. If you want godoc to display syscall documentation for another
11// system, set $GOOS and $GOARCH to the desired system. For example, if
12// you want to view documentation for freebsd/arm on linux/amd64, set $GOOS
13// to freebsd and $GOARCH to arm.
14//
15// The primary use of this package is inside other packages that provide a more
16// portable interface to the system, such as "os", "time" and "net". Use
17// those packages rather than this one if you can.
18//
19// For details of the functions and data types in this package consult
20// the manuals for the appropriate operating system.
21//
22// These calls return err == nil to indicate success; otherwise
23// err represents an operating system error describing the failure and
24// holds a value of type syscall.Errno.
25package windows // import "golang.org/x/sys/windows"
26
27import (
28 "bytes"
29 "strings"
30 "syscall"
31 "unsafe"
32)
33
34// ByteSliceFromString returns a NUL-terminated slice of bytes
35// containing the text of s. If s contains a NUL byte at any
36// location, it returns (nil, syscall.EINVAL).
37func ByteSliceFromString(s string) ([]byte, error) {
38 if strings.IndexByte(s, 0) != -1 {
39 return nil, syscall.EINVAL
40 }
41 a := make([]byte, len(s)+1)
42 copy(a, s)
43 return a, nil
44}
45
46// BytePtrFromString returns a pointer to a NUL-terminated array of
47// bytes containing the text of s. If s contains a NUL byte at any
48// location, it returns (nil, syscall.EINVAL).
49func BytePtrFromString(s string) (*byte, error) {
50 a, err := ByteSliceFromString(s)
51 if err != nil {
52 return nil, err
53 }
54 return &a[0], nil
55}
56
57// ByteSliceToString returns a string form of the text represented by the slice s, with a terminating NUL and any
58// bytes after the NUL removed.
59func ByteSliceToString(s []byte) string {
60 if i := bytes.IndexByte(s, 0); i != -1 {
61 s = s[:i]
62 }
63 return string(s)
64}
65
66// BytePtrToString takes a pointer to a sequence of text and returns the corresponding string.
67// If the pointer is nil, it returns the empty string. It assumes that the text sequence is terminated
68// at a zero byte; if the zero byte is not present, the program may crash.
69func BytePtrToString(p *byte) string {
70 if p == nil {
71 return ""
72 }
73 if *p == 0 {
74 return ""
75 }
76
77 // Find NUL terminator.
78 n := 0
79 for ptr := unsafe.Pointer(p); *(*byte)(ptr) != 0; n++ {
80 ptr = unsafe.Pointer(uintptr(ptr) + 1)
81 }
82
83 return string(unsafe.Slice(p, n))
84}
85
86// Single-word zero for use when we need a valid pointer to 0 bytes.
87// See mksyscall.pl.
88var _zero uintptr
89
90func (ts *Timespec) Unix() (sec int64, nsec int64) {
91 return int64(ts.Sec), int64(ts.Nsec)
92}
93
94func (tv *Timeval) Unix() (sec int64, nsec int64) {
95 return int64(tv.Sec), int64(tv.Usec) * 1000
96}
97
98func (ts *Timespec) Nano() int64 {
99 return int64(ts.Sec)*1e9 + int64(ts.Nsec)
100}
101
102func (tv *Timeval) Nano() int64 {
103 return int64(tv.Sec)*1e9 + int64(tv.Usec)*1000
104}