vendor/golang.org/x/sys/windows/syscall.go
changeset 265 05c40b36d3b2
parent 262 8d3354485fc3
child 268 4dd196a4ee7c
equal deleted inserted replaced
264:8f478162d991 265:05c40b36d3b2
       
     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 // +build windows
       
     7 
       
     8 // Package windows contains an interface to the low-level operating system
       
     9 // primitives. OS details vary depending on the underlying system, and
       
    10 // by default, godoc will display the OS-specific documentation for the current
       
    11 // system. If you want godoc to display syscall documentation for another
       
    12 // system, set $GOOS and $GOARCH to the desired system. For example, if
       
    13 // you want to view documentation for freebsd/arm on linux/amd64, set $GOOS
       
    14 // to freebsd and $GOARCH to arm.
       
    15 //
       
    16 // The primary use of this package is inside other packages that provide a more
       
    17 // portable interface to the system, such as "os", "time" and "net".  Use
       
    18 // those packages rather than this one if you can.
       
    19 //
       
    20 // For details of the functions and data types in this package consult
       
    21 // the manuals for the appropriate operating system.
       
    22 //
       
    23 // These calls return err == nil to indicate success; otherwise
       
    24 // err represents an operating system error describing the failure and
       
    25 // holds a value of type syscall.Errno.
       
    26 package windows // import "golang.org/x/sys/windows"
       
    27 
       
    28 import (
       
    29 	"bytes"
       
    30 	"strings"
       
    31 	"syscall"
       
    32 	"unsafe"
       
    33 )
       
    34 
       
    35 // ByteSliceFromString returns a NUL-terminated slice of bytes
       
    36 // containing the text of s. If s contains a NUL byte at any
       
    37 // location, it returns (nil, syscall.EINVAL).
       
    38 func ByteSliceFromString(s string) ([]byte, error) {
       
    39 	if strings.IndexByte(s, 0) != -1 {
       
    40 		return nil, syscall.EINVAL
       
    41 	}
       
    42 	a := make([]byte, len(s)+1)
       
    43 	copy(a, s)
       
    44 	return a, nil
       
    45 }
       
    46 
       
    47 // BytePtrFromString returns a pointer to a NUL-terminated array of
       
    48 // bytes containing the text of s. If s contains a NUL byte at any
       
    49 // location, it returns (nil, syscall.EINVAL).
       
    50 func BytePtrFromString(s string) (*byte, error) {
       
    51 	a, err := ByteSliceFromString(s)
       
    52 	if err != nil {
       
    53 		return nil, err
       
    54 	}
       
    55 	return &a[0], nil
       
    56 }
       
    57 
       
    58 // ByteSliceToString returns a string form of the text represented by the slice s, with a terminating NUL and any
       
    59 // bytes after the NUL removed.
       
    60 func ByteSliceToString(s []byte) string {
       
    61 	if i := bytes.IndexByte(s, 0); i != -1 {
       
    62 		s = s[:i]
       
    63 	}
       
    64 	return string(s)
       
    65 }
       
    66 
       
    67 // BytePtrToString takes a pointer to a sequence of text and returns the corresponding string.
       
    68 // If the pointer is nil, it returns the empty string. It assumes that the text sequence is terminated
       
    69 // at a zero byte; if the zero byte is not present, the program may crash.
       
    70 func BytePtrToString(p *byte) string {
       
    71 	if p == nil {
       
    72 		return ""
       
    73 	}
       
    74 	if *p == 0 {
       
    75 		return ""
       
    76 	}
       
    77 
       
    78 	// Find NUL terminator.
       
    79 	n := 0
       
    80 	for ptr := unsafe.Pointer(p); *(*byte)(ptr) != 0; n++ {
       
    81 		ptr = unsafe.Pointer(uintptr(ptr) + 1)
       
    82 	}
       
    83 
       
    84 	return string(unsafe.Slice(p, n))
       
    85 }
       
    86 
       
    87 // Single-word zero for use when we need a valid pointer to 0 bytes.
       
    88 // See mksyscall.pl.
       
    89 var _zero uintptr
       
    90 
       
    91 func (ts *Timespec) Unix() (sec int64, nsec int64) {
       
    92 	return int64(ts.Sec), int64(ts.Nsec)
       
    93 }
       
    94 
       
    95 func (tv *Timeval) Unix() (sec int64, nsec int64) {
       
    96 	return int64(tv.Sec), int64(tv.Usec) * 1000
       
    97 }
       
    98 
       
    99 func (ts *Timespec) Nano() int64 {
       
   100 	return int64(ts.Sec)*1e9 + int64(ts.Nsec)
       
   101 }
       
   102 
       
   103 func (tv *Timeval) Nano() int64 {
       
   104 	return int64(tv.Sec)*1e9 + int64(tv.Usec)*1000
       
   105 }