github.com/maenmax/kairep@v0.0.0-20210218001208-55bf3df36788/src/golang.org/x/sys/windows/syscall_windows.go (about)

     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  // Windows system calls.
     6  
     7  package windows
     8  
     9  import (
    10  	errorspkg "errors"
    11  	"sync"
    12  	"syscall"
    13  	"unicode/utf16"
    14  	"unsafe"
    15  )
    16  
    17  type Handle uintptr
    18  
    19  const InvalidHandle = ^Handle(0)
    20  
    21  // StringToUTF16 is deprecated. Use UTF16FromString instead.
    22  // If s contains a NUL byte this function panics instead of
    23  // returning an error.
    24  func StringToUTF16(s string) []uint16 {
    25  	a, err := UTF16FromString(s)
    26  	if err != nil {
    27  		panic("windows: string with NUL passed to StringToUTF16")
    28  	}
    29  	return a
    30  }
    31  
    32  // UTF16FromString returns the UTF-16 encoding of the UTF-8 string
    33  // s, with a terminating NUL added. If s contains a NUL byte at any
    34  // location, it returns (nil, syscall.EINVAL).
    35  func UTF16FromString(s string) ([]uint16, error) {
    36  	for i := 0; i < len(s); i++ {
    37  		if s[i] == 0 {
    38  			return nil, syscall.EINVAL
    39  		}
    40  	}
    41  	return utf16.Encode([]rune(s + "\x00")), nil
    42  }
    43  
    44  // UTF16ToString returns the UTF-8 encoding of the UTF-16 sequence s,
    45  // with a terminating NUL removed.
    46  func UTF16ToString(s []uint16) string {
    47  	for i, v := range s {
    48  		if v == 0 {
    49  			s = s[0:i]
    50  			break
    51  		}
    52  	}
    53  	return string(utf16.Decode(s))
    54  }
    55  
    56  // StringToUTF16Ptr is deprecated. Use UTF16PtrFromString instead.
    57  // If s contains a NUL byte this function panics instead of
    58  // returning an error.
    59  func StringToUTF16Ptr(s string) *uint16 { return &StringToUTF16(s)[0] }
    60  
    61  // UTF16PtrFromString returns pointer to the UTF-16 encoding of
    62  // the UTF-8 string s, with a terminating NUL added. If s
    63  // contains a NUL byte at any location, it returns (nil, syscall.EINVAL).
    64  func UTF16PtrFromString(s string) (*uint16, error) {
    65  	a, err := UTF16FromString(s)
    66  	if err != nil {
    67  		return nil, err
    68  	}
    69  	return &a[0], nil
    70  }
    71  
    72  func Getpagesize() int { return 4096 }
    73  
    74  // Converts a Go function to a function pointer conforming
    75  // to the stdcall or cdecl calling convention.  This is useful when
    76  // interoperating with Windows code requiring callbacks.
    77  // Implemented in runtime/syscall_windows.goc
    78  func NewCallback(fn interface{}) uintptr
    79  func NewCallbackCDecl(fn interface{}) uintptr
    80  
    81  // windows api calls
    82  
    83  //sys	GetLastError() (lasterr error)
    84  //sys	LoadLibrary(libname string) (handle Handle, err error) = LoadLibraryW
    85  //sys	LoadLibraryEx(libname string, zero Handle, flags uintptr) (handle Handle, err error) = LoadLibraryExW
    86  //sys	FreeLibrary(handle Handle) (err error)
    87  //sys	GetProcAddress(module Handle, procname string) (proc uintptr, err error)
    88  //sys	GetVersion() (ver uint32, err error)
    89  //sys	FormatMessage(flags uint32, msgsrc uintptr, msgid uint32, langid uint32, buf []uint16, args *byte) (n uint32, err error) = FormatMessageW
    90  //sys	ExitProcess(exitcode uint32)
    91  //sys	CreateFile(name *uint16, access uint32, mode uint32, sa *SecurityAttributes, createmode uint32, attrs uint32, templatefile int32) (handle Handle, err error) [failretval==InvalidHandle] = CreateFileW
    92  //sys	ReadFile(handle Handle, buf []byte, done *uint32, overlapped *Overlapped) (err error)
    93  //sys	WriteFile(handle Handle, buf []byte, done *uint32, overlapped *Overlapped) (err error)
    94  //sys	SetFilePointer(handle Handle, lowoffset int32, highoffsetptr *int32, whence uint32) (newlowoffset uint32, err error) [failretval==0xffffffff]
    95  //sys	CloseHandle(handle Handle) (err error)
    96  //sys	GetStdHandle(stdhandle int) (handle Handle, err error) [failretval==InvalidHandle]
    97  //sys	findFirstFile1(name *uint16, data *win32finddata1) (handle Handle, err error) [failretval==InvalidHandle] = FindFirstFileW
    98  //sys	findNextFile1(handle Handle, data *win32finddata1) (err error) = FindNextFileW
    99  //sys	FindClose(handle Handle) (err error)
   100  //sys	GetFileInformationByHandle(handle Handle, data *ByHandleFileInformation) (err error)
   101  //sys	GetCurrentDirectory(buflen uint32, buf *uint16) (n uint32, err error) = GetCurrentDirectoryW
   102  //sys	SetCurrentDirectory(path *uint16) (err error) = SetCurrentDirectoryW
   103  //sys	CreateDirectory(path *uint16, sa *SecurityAttributes) (err error) = CreateDirectoryW
   104  //sys	RemoveDirectory(path *uint16) (err error) = RemoveDirectoryW
   105  //sys	DeleteFile(path *uint16) (err error) = DeleteFileW
   106  //sys	MoveFile(from *uint16, to *uint16) (err error) = MoveFileW
   107  //sys	MoveFileEx(from *uint16, to *uint16, flags uint32) (err error) = MoveFileExW
   108  //sys	GetComputerName(buf *uint16, n *uint32) (err error) = GetComputerNameW
   109  //sys	GetComputerNameEx(nametype uint32, buf *uint16, n *uint32) (err error) = GetComputerNameExW
   110  //sys	SetEndOfFile(handle Handle) (err error)
   111  //sys	GetSystemTimeAsFileTime(time *Filetime)
   112  //sys	GetTimeZoneInformation(tzi *Timezoneinformation) (rc uint32, err error) [failretval==0xffffffff]
   113  //sys	CreateIoCompletionPort(filehandle Handle, cphandle Handle, key uint32, threadcnt uint32) (handle Handle, err error)
   114  //sys	GetQueuedCompletionStatus(cphandle Handle, qty *uint32, key *uint32, overlapped **Overlapped, timeout uint32) (err error)
   115  //sys	PostQueuedCompletionStatus(cphandle Handle, qty uint32, key uint32, overlapped *Overlapped) (err error)
   116  //sys	CancelIo(s Handle) (err error)
   117  //sys	CancelIoEx(s Handle, o *Overlapped) (err error)
   118  //sys	CreateProcess(appName *uint16, commandLine *uint16, procSecurity *SecurityAttributes, threadSecurity *SecurityAttributes, inheritHandles bool, creationFlags uint32, env *uint16, currentDir *uint16, startupInfo *StartupInfo, outProcInfo *ProcessInformation) (err error) = CreateProcessW
   119  //sys	OpenProcess(da uint32, inheritHandle bool, pid uint32) (handle Handle, err error)
   120  //sys	TerminateProcess(handle Handle, exitcode uint32) (err error)
   121  //sys	GetExitCodeProcess(handle Handle, exitcode *uint32) (err error)
   122  //sys	GetStartupInfo(startupInfo *StartupInfo) (err error) = GetStartupInfoW
   123  //sys	GetCurrentProcess() (pseudoHandle Handle, err error)
   124  //sys	GetProcessTimes(handle Handle, creationTime *Filetime, exitTime *Filetime, kernelTime *Filetime, userTime *Filetime) (err error)
   125  //sys	DuplicateHandle(hSourceProcessHandle Handle, hSourceHandle Handle, hTargetProcessHandle Handle, lpTargetHandle *Handle, dwDesiredAccess uint32, bInheritHandle bool, dwOptions uint32) (err error)
   126  //sys	WaitForSingleObject(handle Handle, waitMilliseconds uint32) (event uint32, err error) [failretval==0xffffffff]
   127  //sys	GetTempPath(buflen uint32, buf *uint16) (n uint32, err error) = GetTempPathW
   128  //sys	CreatePipe(readhandle *Handle, writehandle *Handle, sa *SecurityAttributes, size uint32) (err error)
   129  //sys	GetFileType(filehandle Handle) (n uint32, err error)
   130  //sys	CryptAcquireContext(provhandle *Handle, container *uint16, provider *uint16, provtype uint32, flags uint32) (err error) = advapi32.CryptAcquireContextW
   131  //sys	CryptReleaseContext(provhandle Handle, flags uint32) (err error) = advapi32.CryptReleaseContext
   132  //sys	CryptGenRandom(provhandle Handle, buflen uint32, buf *byte) (err error) = advapi32.CryptGenRandom
   133  //sys	GetEnvironmentStrings() (envs *uint16, err error) [failretval==nil] = kernel32.GetEnvironmentStringsW
   134  //sys	FreeEnvironmentStrings(envs *uint16) (err error) = kernel32.FreeEnvironmentStringsW
   135  //sys	GetEnvironmentVariable(name *uint16, buffer *uint16, size uint32) (n uint32, err error) = kernel32.GetEnvironmentVariableW
   136  //sys	SetEnvironmentVariable(name *uint16, value *uint16) (err error) = kernel32.SetEnvironmentVariableW
   137  //sys	SetFileTime(handle Handle, ctime *Filetime, atime *Filetime, wtime *Filetime) (err error)
   138  //sys	GetFileAttributes(name *uint16) (attrs uint32, err error) [failretval==INVALID_FILE_ATTRIBUTES] = kernel32.GetFileAttributesW
   139  //sys	SetFileAttributes(name *uint16, attrs uint32) (err error) = kernel32.SetFileAttributesW
   140  //sys	GetFileAttributesEx(name *uint16, level uint32, info *byte) (err error) = kernel32.GetFileAttributesExW
   141  //sys	GetCommandLine() (cmd *uint16) = kernel32.GetCommandLineW
   142  //sys	CommandLineToArgv(cmd *uint16, argc *int32) (argv *[8192]*[8192]uint16, err error) [failretval==nil] = shell32.CommandLineToArgvW
   143  //sys	LocalFree(hmem Handle) (handle Handle, err error) [failretval!=0]
   144  //sys	SetHandleInformation(handle Handle, mask uint32, flags uint32) (err error)
   145  //sys	FlushFileBuffers(handle Handle) (err error)
   146  //sys	GetFullPathName(path *uint16, buflen uint32, buf *uint16, fname **uint16) (n uint32, err error) = kernel32.GetFullPathNameW
   147  //sys	GetLongPathName(path *uint16, buf *uint16, buflen uint32) (n uint32, err error) = kernel32.GetLongPathNameW
   148  //sys	GetShortPathName(longpath *uint16, shortpath *uint16, buflen uint32) (n uint32, err error) = kernel32.GetShortPathNameW
   149  //sys	CreateFileMapping(fhandle Handle, sa *SecurityAttributes, prot uint32, maxSizeHigh uint32, maxSizeLow uint32, name *uint16) (handle Handle, err error) = kernel32.CreateFileMappingW
   150  //sys	MapViewOfFile(handle Handle, access uint32, offsetHigh uint32, offsetLow uint32, length uintptr) (addr uintptr, err error)
   151  //sys	UnmapViewOfFile(addr uintptr) (err error)
   152  //sys	FlushViewOfFile(addr uintptr, length uintptr) (err error)
   153  //sys	VirtualLock(addr uintptr, length uintptr) (err error)
   154  //sys	VirtualUnlock(addr uintptr, length uintptr) (err error)
   155  //sys	TransmitFile(s Handle, handle Handle, bytesToWrite uint32, bytsPerSend uint32, overlapped *Overlapped, transmitFileBuf *TransmitFileBuffers, flags uint32) (err error) = mswsock.TransmitFile
   156  //sys	ReadDirectoryChanges(handle Handle, buf *byte, buflen uint32, watchSubTree bool, mask uint32, retlen *uint32, overlapped *Overlapped, completionRoutine uintptr) (err error) = kernel32.ReadDirectoryChangesW
   157  //sys	CertOpenSystemStore(hprov Handle, name *uint16) (store Handle, err error) = crypt32.CertOpenSystemStoreW
   158  //sys   CertOpenStore(storeProvider uintptr, msgAndCertEncodingType uint32, cryptProv uintptr, flags uint32, para uintptr) (handle Handle, err error) [failretval==InvalidHandle] = crypt32.CertOpenStore
   159  //sys	CertEnumCertificatesInStore(store Handle, prevContext *CertContext) (context *CertContext, err error) [failretval==nil] = crypt32.CertEnumCertificatesInStore
   160  //sys   CertAddCertificateContextToStore(store Handle, certContext *CertContext, addDisposition uint32, storeContext **CertContext) (err error) = crypt32.CertAddCertificateContextToStore
   161  //sys	CertCloseStore(store Handle, flags uint32) (err error) = crypt32.CertCloseStore
   162  //sys   CertGetCertificateChain(engine Handle, leaf *CertContext, time *Filetime, additionalStore Handle, para *CertChainPara, flags uint32, reserved uintptr, chainCtx **CertChainContext) (err error) = crypt32.CertGetCertificateChain
   163  //sys   CertFreeCertificateChain(ctx *CertChainContext) = crypt32.CertFreeCertificateChain
   164  //sys   CertCreateCertificateContext(certEncodingType uint32, certEncoded *byte, encodedLen uint32) (context *CertContext, err error) [failretval==nil] = crypt32.CertCreateCertificateContext
   165  //sys   CertFreeCertificateContext(ctx *CertContext) (err error) = crypt32.CertFreeCertificateContext
   166  //sys   CertVerifyCertificateChainPolicy(policyOID uintptr, chain *CertChainContext, para *CertChainPolicyPara, status *CertChainPolicyStatus) (err error) = crypt32.CertVerifyCertificateChainPolicy
   167  //sys	RegOpenKeyEx(key Handle, subkey *uint16, options uint32, desiredAccess uint32, result *Handle) (regerrno error) = advapi32.RegOpenKeyExW
   168  //sys	RegCloseKey(key Handle) (regerrno error) = advapi32.RegCloseKey
   169  //sys	RegQueryInfoKey(key Handle, class *uint16, classLen *uint32, reserved *uint32, subkeysLen *uint32, maxSubkeyLen *uint32, maxClassLen *uint32, valuesLen *uint32, maxValueNameLen *uint32, maxValueLen *uint32, saLen *uint32, lastWriteTime *Filetime) (regerrno error) = advapi32.RegQueryInfoKeyW
   170  //sys	RegEnumKeyEx(key Handle, index uint32, name *uint16, nameLen *uint32, reserved *uint32, class *uint16, classLen *uint32, lastWriteTime *Filetime) (regerrno error) = advapi32.RegEnumKeyExW
   171  //sys	RegQueryValueEx(key Handle, name *uint16, reserved *uint32, valtype *uint32, buf *byte, buflen *uint32) (regerrno error) = advapi32.RegQueryValueExW
   172  //sys	getCurrentProcessId() (pid uint32) = kernel32.GetCurrentProcessId
   173  //sys	GetConsoleMode(console Handle, mode *uint32) (err error) = kernel32.GetConsoleMode
   174  //sys	WriteConsole(console Handle, buf *uint16, towrite uint32, written *uint32, reserved *byte) (err error) = kernel32.WriteConsoleW
   175  //sys	ReadConsole(console Handle, buf *uint16, toread uint32, read *uint32, inputControl *byte) (err error) = kernel32.ReadConsoleW
   176  //sys	CreateToolhelp32Snapshot(flags uint32, processId uint32) (handle Handle, err error) [failretval==InvalidHandle] = kernel32.CreateToolhelp32Snapshot
   177  //sys	Process32First(snapshot Handle, procEntry *ProcessEntry32) (err error) = kernel32.Process32FirstW
   178  //sys	Process32Next(snapshot Handle, procEntry *ProcessEntry32) (err error) = kernel32.Process32NextW
   179  //sys	DeviceIoControl(handle Handle, ioControlCode uint32, inBuffer *byte, inBufferSize uint32, outBuffer *byte, outBufferSize uint32, bytesReturned *uint32, overlapped *Overlapped) (err error)
   180  // This function returns 1 byte BOOLEAN rather than the 4 byte BOOL.
   181  //sys	CreateSymbolicLink(symlinkfilename *uint16, targetfilename *uint16, flags uint32) (err error) [failretval&0xff==0] = CreateSymbolicLinkW
   182  //sys	CreateHardLink(filename *uint16, existingfilename *uint16, reserved uintptr) (err error) [failretval&0xff==0] = CreateHardLinkW
   183  //sys	GetCurrentThreadId() (id uint32)
   184  //sys	CreateEvent(eventAttrs *syscall.SecurityAttributes, manualReset uint32, initialState uint32, name *uint16) (handle Handle, err error) = kernel32.CreateEventW
   185  //sys	SetEvent(event Handle) (err error) = kernel32.SetEvent
   186  
   187  // syscall interface implementation for other packages
   188  
   189  func Exit(code int) { ExitProcess(uint32(code)) }
   190  
   191  func makeInheritSa() *SecurityAttributes {
   192  	var sa SecurityAttributes
   193  	sa.Length = uint32(unsafe.Sizeof(sa))
   194  	sa.InheritHandle = 1
   195  	return &sa
   196  }
   197  
   198  func Open(path string, mode int, perm uint32) (fd Handle, err error) {
   199  	if len(path) == 0 {
   200  		return InvalidHandle, ERROR_FILE_NOT_FOUND
   201  	}
   202  	pathp, err := UTF16PtrFromString(path)
   203  	if err != nil {
   204  		return InvalidHandle, err
   205  	}
   206  	var access uint32
   207  	switch mode & (O_RDONLY | O_WRONLY | O_RDWR) {
   208  	case O_RDONLY:
   209  		access = GENERIC_READ
   210  	case O_WRONLY:
   211  		access = GENERIC_WRITE
   212  	case O_RDWR:
   213  		access = GENERIC_READ | GENERIC_WRITE
   214  	}
   215  	if mode&O_CREAT != 0 {
   216  		access |= GENERIC_WRITE
   217  	}
   218  	if mode&O_APPEND != 0 {
   219  		access &^= GENERIC_WRITE
   220  		access |= FILE_APPEND_DATA
   221  	}
   222  	sharemode := uint32(FILE_SHARE_READ | FILE_SHARE_WRITE)
   223  	var sa *SecurityAttributes
   224  	if mode&O_CLOEXEC == 0 {
   225  		sa = makeInheritSa()
   226  	}
   227  	var createmode uint32
   228  	switch {
   229  	case mode&(O_CREAT|O_EXCL) == (O_CREAT | O_EXCL):
   230  		createmode = CREATE_NEW
   231  	case mode&(O_CREAT|O_TRUNC) == (O_CREAT | O_TRUNC):
   232  		createmode = CREATE_ALWAYS
   233  	case mode&O_CREAT == O_CREAT:
   234  		createmode = OPEN_ALWAYS
   235  	case mode&O_TRUNC == O_TRUNC:
   236  		createmode = TRUNCATE_EXISTING
   237  	default:
   238  		createmode = OPEN_EXISTING
   239  	}
   240  	h, e := CreateFile(pathp, access, sharemode, sa, createmode, FILE_ATTRIBUTE_NORMAL, 0)
   241  	return h, e
   242  }
   243  
   244  func Read(fd Handle, p []byte) (n int, err error) {
   245  	var done uint32
   246  	e := ReadFile(fd, p, &done, nil)
   247  	if e != nil {
   248  		if e == ERROR_BROKEN_PIPE {
   249  			// NOTE(brainman): work around ERROR_BROKEN_PIPE is returned on reading EOF from stdin
   250  			return 0, nil
   251  		}
   252  		return 0, e
   253  	}
   254  	if raceenabled {
   255  		if done > 0 {
   256  			raceWriteRange(unsafe.Pointer(&p[0]), int(done))
   257  		}
   258  		raceAcquire(unsafe.Pointer(&ioSync))
   259  	}
   260  	return int(done), nil
   261  }
   262  
   263  func Write(fd Handle, p []byte) (n int, err error) {
   264  	if raceenabled {
   265  		raceReleaseMerge(unsafe.Pointer(&ioSync))
   266  	}
   267  	var done uint32
   268  	e := WriteFile(fd, p, &done, nil)
   269  	if e != nil {
   270  		return 0, e
   271  	}
   272  	if raceenabled && done > 0 {
   273  		raceReadRange(unsafe.Pointer(&p[0]), int(done))
   274  	}
   275  	return int(done), nil
   276  }
   277  
   278  var ioSync int64
   279  
   280  func Seek(fd Handle, offset int64, whence int) (newoffset int64, err error) {
   281  	var w uint32
   282  	switch whence {
   283  	case 0:
   284  		w = FILE_BEGIN
   285  	case 1:
   286  		w = FILE_CURRENT
   287  	case 2:
   288  		w = FILE_END
   289  	}
   290  	hi := int32(offset >> 32)
   291  	lo := int32(offset)
   292  	// use GetFileType to check pipe, pipe can't do seek
   293  	ft, _ := GetFileType(fd)
   294  	if ft == FILE_TYPE_PIPE {
   295  		return 0, syscall.EPIPE
   296  	}
   297  	rlo, e := SetFilePointer(fd, lo, &hi, w)
   298  	if e != nil {
   299  		return 0, e
   300  	}
   301  	return int64(hi)<<32 + int64(rlo), nil
   302  }
   303  
   304  func Close(fd Handle) (err error) {
   305  	return CloseHandle(fd)
   306  }
   307  
   308  var (
   309  	Stdin  = getStdHandle(STD_INPUT_HANDLE)
   310  	Stdout = getStdHandle(STD_OUTPUT_HANDLE)
   311  	Stderr = getStdHandle(STD_ERROR_HANDLE)
   312  )
   313  
   314  func getStdHandle(h int) (fd Handle) {
   315  	r, _ := GetStdHandle(h)
   316  	CloseOnExec(r)
   317  	return r
   318  }
   319  
   320  const ImplementsGetwd = true
   321  
   322  func Getwd() (wd string, err error) {
   323  	b := make([]uint16, 300)
   324  	n, e := GetCurrentDirectory(uint32(len(b)), &b[0])
   325  	if e != nil {
   326  		return "", e
   327  	}
   328  	return string(utf16.Decode(b[0:n])), nil
   329  }
   330  
   331  func Chdir(path string) (err error) {
   332  	pathp, err := UTF16PtrFromString(path)
   333  	if err != nil {
   334  		return err
   335  	}
   336  	return SetCurrentDirectory(pathp)
   337  }
   338  
   339  func Mkdir(path string, mode uint32) (err error) {
   340  	pathp, err := UTF16PtrFromString(path)
   341  	if err != nil {
   342  		return err
   343  	}
   344  	return CreateDirectory(pathp, nil)
   345  }
   346  
   347  func Rmdir(path string) (err error) {
   348  	pathp, err := UTF16PtrFromString(path)
   349  	if err != nil {
   350  		return err
   351  	}
   352  	return RemoveDirectory(pathp)
   353  }
   354  
   355  func Unlink(path string) (err error) {
   356  	pathp, err := UTF16PtrFromString(path)
   357  	if err != nil {
   358  		return err
   359  	}
   360  	return DeleteFile(pathp)
   361  }
   362  
   363  func Rename(oldpath, newpath string) (err error) {
   364  	from, err := UTF16PtrFromString(oldpath)
   365  	if err != nil {
   366  		return err
   367  	}
   368  	to, err := UTF16PtrFromString(newpath)
   369  	if err != nil {
   370  		return err
   371  	}
   372  	return MoveFileEx(from, to, MOVEFILE_REPLACE_EXISTING)
   373  }
   374  
   375  func ComputerName() (name string, err error) {
   376  	var n uint32 = MAX_COMPUTERNAME_LENGTH + 1
   377  	b := make([]uint16, n)
   378  	e := GetComputerName(&b[0], &n)
   379  	if e != nil {
   380  		return "", e
   381  	}
   382  	return string(utf16.Decode(b[0:n])), nil
   383  }
   384  
   385  func Ftruncate(fd Handle, length int64) (err error) {
   386  	curoffset, e := Seek(fd, 0, 1)
   387  	if e != nil {
   388  		return e
   389  	}
   390  	defer Seek(fd, curoffset, 0)
   391  	_, e = Seek(fd, length, 0)
   392  	if e != nil {
   393  		return e
   394  	}
   395  	e = SetEndOfFile(fd)
   396  	if e != nil {
   397  		return e
   398  	}
   399  	return nil
   400  }
   401  
   402  func Gettimeofday(tv *Timeval) (err error) {
   403  	var ft Filetime
   404  	GetSystemTimeAsFileTime(&ft)
   405  	*tv = NsecToTimeval(ft.Nanoseconds())
   406  	return nil
   407  }
   408  
   409  func Pipe(p []Handle) (err error) {
   410  	if len(p) != 2 {
   411  		return syscall.EINVAL
   412  	}
   413  	var r, w Handle
   414  	e := CreatePipe(&r, &w, makeInheritSa(), 0)
   415  	if e != nil {
   416  		return e
   417  	}
   418  	p[0] = r
   419  	p[1] = w
   420  	return nil
   421  }
   422  
   423  func Utimes(path string, tv []Timeval) (err error) {
   424  	if len(tv) != 2 {
   425  		return syscall.EINVAL
   426  	}
   427  	pathp, e := UTF16PtrFromString(path)
   428  	if e != nil {
   429  		return e
   430  	}
   431  	h, e := CreateFile(pathp,
   432  		FILE_WRITE_ATTRIBUTES, FILE_SHARE_WRITE, nil,
   433  		OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, 0)
   434  	if e != nil {
   435  		return e
   436  	}
   437  	defer Close(h)
   438  	a := NsecToFiletime(tv[0].Nanoseconds())
   439  	w := NsecToFiletime(tv[1].Nanoseconds())
   440  	return SetFileTime(h, nil, &a, &w)
   441  }
   442  
   443  func UtimesNano(path string, ts []Timespec) (err error) {
   444  	if len(ts) != 2 {
   445  		return syscall.EINVAL
   446  	}
   447  	pathp, e := UTF16PtrFromString(path)
   448  	if e != nil {
   449  		return e
   450  	}
   451  	h, e := CreateFile(pathp,
   452  		FILE_WRITE_ATTRIBUTES, FILE_SHARE_WRITE, nil,
   453  		OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, 0)
   454  	if e != nil {
   455  		return e
   456  	}
   457  	defer Close(h)
   458  	a := NsecToFiletime(TimespecToNsec(ts[0]))
   459  	w := NsecToFiletime(TimespecToNsec(ts[1]))
   460  	return SetFileTime(h, nil, &a, &w)
   461  }
   462  
   463  func Fsync(fd Handle) (err error) {
   464  	return FlushFileBuffers(fd)
   465  }
   466  
   467  func Chmod(path string, mode uint32) (err error) {
   468  	if mode == 0 {
   469  		return syscall.EINVAL
   470  	}
   471  	p, e := UTF16PtrFromString(path)
   472  	if e != nil {
   473  		return e
   474  	}
   475  	attrs, e := GetFileAttributes(p)
   476  	if e != nil {
   477  		return e
   478  	}
   479  	if mode&S_IWRITE != 0 {
   480  		attrs &^= FILE_ATTRIBUTE_READONLY
   481  	} else {
   482  		attrs |= FILE_ATTRIBUTE_READONLY
   483  	}
   484  	return SetFileAttributes(p, attrs)
   485  }
   486  
   487  func LoadCancelIoEx() error {
   488  	return procCancelIoEx.Find()
   489  }
   490  
   491  func LoadSetFileCompletionNotificationModes() error {
   492  	return procSetFileCompletionNotificationModes.Find()
   493  }
   494  
   495  // net api calls
   496  
   497  const socket_error = uintptr(^uint32(0))
   498  
   499  //sys	WSAStartup(verreq uint32, data *WSAData) (sockerr error) = ws2_32.WSAStartup
   500  //sys	WSACleanup() (err error) [failretval==socket_error] = ws2_32.WSACleanup
   501  //sys	WSAIoctl(s Handle, iocc uint32, inbuf *byte, cbif uint32, outbuf *byte, cbob uint32, cbbr *uint32, overlapped *Overlapped, completionRoutine uintptr) (err error) [failretval==socket_error] = ws2_32.WSAIoctl
   502  //sys	socket(af int32, typ int32, protocol int32) (handle Handle, err error) [failretval==InvalidHandle] = ws2_32.socket
   503  //sys	Setsockopt(s Handle, level int32, optname int32, optval *byte, optlen int32) (err error) [failretval==socket_error] = ws2_32.setsockopt
   504  //sys	Getsockopt(s Handle, level int32, optname int32, optval *byte, optlen *int32) (err error) [failretval==socket_error] = ws2_32.getsockopt
   505  //sys	bind(s Handle, name unsafe.Pointer, namelen int32) (err error) [failretval==socket_error] = ws2_32.bind
   506  //sys	connect(s Handle, name unsafe.Pointer, namelen int32) (err error) [failretval==socket_error] = ws2_32.connect
   507  //sys	getsockname(s Handle, rsa *RawSockaddrAny, addrlen *int32) (err error) [failretval==socket_error] = ws2_32.getsockname
   508  //sys	getpeername(s Handle, rsa *RawSockaddrAny, addrlen *int32) (err error) [failretval==socket_error] = ws2_32.getpeername
   509  //sys	listen(s Handle, backlog int32) (err error) [failretval==socket_error] = ws2_32.listen
   510  //sys	shutdown(s Handle, how int32) (err error) [failretval==socket_error] = ws2_32.shutdown
   511  //sys	Closesocket(s Handle) (err error) [failretval==socket_error] = ws2_32.closesocket
   512  //sys	AcceptEx(ls Handle, as Handle, buf *byte, rxdatalen uint32, laddrlen uint32, raddrlen uint32, recvd *uint32, overlapped *Overlapped) (err error) = mswsock.AcceptEx
   513  //sys	GetAcceptExSockaddrs(buf *byte, rxdatalen uint32, laddrlen uint32, raddrlen uint32, lrsa **RawSockaddrAny, lrsalen *int32, rrsa **RawSockaddrAny, rrsalen *int32) = mswsock.GetAcceptExSockaddrs
   514  //sys	WSARecv(s Handle, bufs *WSABuf, bufcnt uint32, recvd *uint32, flags *uint32, overlapped *Overlapped, croutine *byte) (err error) [failretval==socket_error] = ws2_32.WSARecv
   515  //sys	WSASend(s Handle, bufs *WSABuf, bufcnt uint32, sent *uint32, flags uint32, overlapped *Overlapped, croutine *byte) (err error) [failretval==socket_error] = ws2_32.WSASend
   516  //sys	WSARecvFrom(s Handle, bufs *WSABuf, bufcnt uint32, recvd *uint32, flags *uint32,  from *RawSockaddrAny, fromlen *int32, overlapped *Overlapped, croutine *byte) (err error) [failretval==socket_error] = ws2_32.WSARecvFrom
   517  //sys	WSASendTo(s Handle, bufs *WSABuf, bufcnt uint32, sent *uint32, flags uint32, to *RawSockaddrAny, tolen int32,  overlapped *Overlapped, croutine *byte) (err error) [failretval==socket_error] = ws2_32.WSASendTo
   518  //sys	GetHostByName(name string) (h *Hostent, err error) [failretval==nil] = ws2_32.gethostbyname
   519  //sys	GetServByName(name string, proto string) (s *Servent, err error) [failretval==nil] = ws2_32.getservbyname
   520  //sys	Ntohs(netshort uint16) (u uint16) = ws2_32.ntohs
   521  //sys	GetProtoByName(name string) (p *Protoent, err error) [failretval==nil] = ws2_32.getprotobyname
   522  //sys	DnsQuery(name string, qtype uint16, options uint32, extra *byte, qrs **DNSRecord, pr *byte) (status error) = dnsapi.DnsQuery_W
   523  //sys	DnsRecordListFree(rl *DNSRecord, freetype uint32) = dnsapi.DnsRecordListFree
   524  //sys	DnsNameCompare(name1 *uint16, name2 *uint16) (same bool) = dnsapi.DnsNameCompare_W
   525  //sys	GetAddrInfoW(nodename *uint16, servicename *uint16, hints *AddrinfoW, result **AddrinfoW) (sockerr error) = ws2_32.GetAddrInfoW
   526  //sys	FreeAddrInfoW(addrinfo *AddrinfoW) = ws2_32.FreeAddrInfoW
   527  //sys	GetIfEntry(pIfRow *MibIfRow) (errcode error) = iphlpapi.GetIfEntry
   528  //sys	GetAdaptersInfo(ai *IpAdapterInfo, ol *uint32) (errcode error) = iphlpapi.GetAdaptersInfo
   529  //sys	SetFileCompletionNotificationModes(handle Handle, flags uint8) (err error) = kernel32.SetFileCompletionNotificationModes
   530  //sys	WSAEnumProtocols(protocols *int32, protocolBuffer *WSAProtocolInfo, bufferLength *uint32) (n int32, err error) [failretval==-1] = ws2_32.WSAEnumProtocolsW
   531  //sys	GetAdaptersAddresses(family uint32, flags uint32, reserved uintptr, adapterAddresses *IpAdapterAddresses, sizePointer *uint32) (errcode error) = iphlpapi.GetAdaptersAddresses
   532  //sys	GetACP() (acp uint32) = kernel32.GetACP
   533  //sys	MultiByteToWideChar(codePage uint32, dwFlags uint32, str *byte, nstr int32, wchar *uint16, nwchar int32) (nwrite int32, err error) = kernel32.MultiByteToWideChar
   534  
   535  // For testing: clients can set this flag to force
   536  // creation of IPv6 sockets to return EAFNOSUPPORT.
   537  var SocketDisableIPv6 bool
   538  
   539  type RawSockaddrInet4 struct {
   540  	Family uint16
   541  	Port   uint16
   542  	Addr   [4]byte /* in_addr */
   543  	Zero   [8]uint8
   544  }
   545  
   546  type RawSockaddrInet6 struct {
   547  	Family   uint16
   548  	Port     uint16
   549  	Flowinfo uint32
   550  	Addr     [16]byte /* in6_addr */
   551  	Scope_id uint32
   552  }
   553  
   554  type RawSockaddr struct {
   555  	Family uint16
   556  	Data   [14]int8
   557  }
   558  
   559  type RawSockaddrAny struct {
   560  	Addr RawSockaddr
   561  	Pad  [96]int8
   562  }
   563  
   564  type Sockaddr interface {
   565  	sockaddr() (ptr unsafe.Pointer, len int32, err error) // lowercase; only we can define Sockaddrs
   566  }
   567  
   568  type SockaddrInet4 struct {
   569  	Port int
   570  	Addr [4]byte
   571  	raw  RawSockaddrInet4
   572  }
   573  
   574  func (sa *SockaddrInet4) sockaddr() (unsafe.Pointer, int32, error) {
   575  	if sa.Port < 0 || sa.Port > 0xFFFF {
   576  		return nil, 0, syscall.EINVAL
   577  	}
   578  	sa.raw.Family = AF_INET
   579  	p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port))
   580  	p[0] = byte(sa.Port >> 8)
   581  	p[1] = byte(sa.Port)
   582  	for i := 0; i < len(sa.Addr); i++ {
   583  		sa.raw.Addr[i] = sa.Addr[i]
   584  	}
   585  	return unsafe.Pointer(&sa.raw), int32(unsafe.Sizeof(sa.raw)), nil
   586  }
   587  
   588  type SockaddrInet6 struct {
   589  	Port   int
   590  	ZoneId uint32
   591  	Addr   [16]byte
   592  	raw    RawSockaddrInet6
   593  }
   594  
   595  func (sa *SockaddrInet6) sockaddr() (unsafe.Pointer, int32, error) {
   596  	if sa.Port < 0 || sa.Port > 0xFFFF {
   597  		return nil, 0, syscall.EINVAL
   598  	}
   599  	sa.raw.Family = AF_INET6
   600  	p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port))
   601  	p[0] = byte(sa.Port >> 8)
   602  	p[1] = byte(sa.Port)
   603  	sa.raw.Scope_id = sa.ZoneId
   604  	for i := 0; i < len(sa.Addr); i++ {
   605  		sa.raw.Addr[i] = sa.Addr[i]
   606  	}
   607  	return unsafe.Pointer(&sa.raw), int32(unsafe.Sizeof(sa.raw)), nil
   608  }
   609  
   610  type SockaddrUnix struct {
   611  	Name string
   612  }
   613  
   614  func (sa *SockaddrUnix) sockaddr() (unsafe.Pointer, int32, error) {
   615  	// TODO(brainman): implement SockaddrUnix.sockaddr()
   616  	return nil, 0, syscall.EWINDOWS
   617  }
   618  
   619  func (rsa *RawSockaddrAny) Sockaddr() (Sockaddr, error) {
   620  	switch rsa.Addr.Family {
   621  	case AF_UNIX:
   622  		return nil, syscall.EWINDOWS
   623  
   624  	case AF_INET:
   625  		pp := (*RawSockaddrInet4)(unsafe.Pointer(rsa))
   626  		sa := new(SockaddrInet4)
   627  		p := (*[2]byte)(unsafe.Pointer(&pp.Port))
   628  		sa.Port = int(p[0])<<8 + int(p[1])
   629  		for i := 0; i < len(sa.Addr); i++ {
   630  			sa.Addr[i] = pp.Addr[i]
   631  		}
   632  		return sa, nil
   633  
   634  	case AF_INET6:
   635  		pp := (*RawSockaddrInet6)(unsafe.Pointer(rsa))
   636  		sa := new(SockaddrInet6)
   637  		p := (*[2]byte)(unsafe.Pointer(&pp.Port))
   638  		sa.Port = int(p[0])<<8 + int(p[1])
   639  		sa.ZoneId = pp.Scope_id
   640  		for i := 0; i < len(sa.Addr); i++ {
   641  			sa.Addr[i] = pp.Addr[i]
   642  		}
   643  		return sa, nil
   644  	}
   645  	return nil, syscall.EAFNOSUPPORT
   646  }
   647  
   648  func Socket(domain, typ, proto int) (fd Handle, err error) {
   649  	if domain == AF_INET6 && SocketDisableIPv6 {
   650  		return InvalidHandle, syscall.EAFNOSUPPORT
   651  	}
   652  	return socket(int32(domain), int32(typ), int32(proto))
   653  }
   654  
   655  func SetsockoptInt(fd Handle, level, opt int, value int) (err error) {
   656  	v := int32(value)
   657  	return Setsockopt(fd, int32(level), int32(opt), (*byte)(unsafe.Pointer(&v)), int32(unsafe.Sizeof(v)))
   658  }
   659  
   660  func Bind(fd Handle, sa Sockaddr) (err error) {
   661  	ptr, n, err := sa.sockaddr()
   662  	if err != nil {
   663  		return err
   664  	}
   665  	return bind(fd, ptr, n)
   666  }
   667  
   668  func Connect(fd Handle, sa Sockaddr) (err error) {
   669  	ptr, n, err := sa.sockaddr()
   670  	if err != nil {
   671  		return err
   672  	}
   673  	return connect(fd, ptr, n)
   674  }
   675  
   676  func Getsockname(fd Handle) (sa Sockaddr, err error) {
   677  	var rsa RawSockaddrAny
   678  	l := int32(unsafe.Sizeof(rsa))
   679  	if err = getsockname(fd, &rsa, &l); err != nil {
   680  		return
   681  	}
   682  	return rsa.Sockaddr()
   683  }
   684  
   685  func Getpeername(fd Handle) (sa Sockaddr, err error) {
   686  	var rsa RawSockaddrAny
   687  	l := int32(unsafe.Sizeof(rsa))
   688  	if err = getpeername(fd, &rsa, &l); err != nil {
   689  		return
   690  	}
   691  	return rsa.Sockaddr()
   692  }
   693  
   694  func Listen(s Handle, n int) (err error) {
   695  	return listen(s, int32(n))
   696  }
   697  
   698  func Shutdown(fd Handle, how int) (err error) {
   699  	return shutdown(fd, int32(how))
   700  }
   701  
   702  func WSASendto(s Handle, bufs *WSABuf, bufcnt uint32, sent *uint32, flags uint32, to Sockaddr, overlapped *Overlapped, croutine *byte) (err error) {
   703  	rsa, l, err := to.sockaddr()
   704  	if err != nil {
   705  		return err
   706  	}
   707  	return WSASendTo(s, bufs, bufcnt, sent, flags, (*RawSockaddrAny)(unsafe.Pointer(rsa)), l, overlapped, croutine)
   708  }
   709  
   710  func LoadGetAddrInfo() error {
   711  	return procGetAddrInfoW.Find()
   712  }
   713  
   714  var connectExFunc struct {
   715  	once sync.Once
   716  	addr uintptr
   717  	err  error
   718  }
   719  
   720  func LoadConnectEx() error {
   721  	connectExFunc.once.Do(func() {
   722  		var s Handle
   723  		s, connectExFunc.err = Socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)
   724  		if connectExFunc.err != nil {
   725  			return
   726  		}
   727  		defer CloseHandle(s)
   728  		var n uint32
   729  		connectExFunc.err = WSAIoctl(s,
   730  			SIO_GET_EXTENSION_FUNCTION_POINTER,
   731  			(*byte)(unsafe.Pointer(&WSAID_CONNECTEX)),
   732  			uint32(unsafe.Sizeof(WSAID_CONNECTEX)),
   733  			(*byte)(unsafe.Pointer(&connectExFunc.addr)),
   734  			uint32(unsafe.Sizeof(connectExFunc.addr)),
   735  			&n, nil, 0)
   736  	})
   737  	return connectExFunc.err
   738  }
   739  
   740  func connectEx(s Handle, name unsafe.Pointer, namelen int32, sendBuf *byte, sendDataLen uint32, bytesSent *uint32, overlapped *Overlapped) (err error) {
   741  	r1, _, e1 := syscall.Syscall9(connectExFunc.addr, 7, uintptr(s), uintptr(name), uintptr(namelen), uintptr(unsafe.Pointer(sendBuf)), uintptr(sendDataLen), uintptr(unsafe.Pointer(bytesSent)), uintptr(unsafe.Pointer(overlapped)), 0, 0)
   742  	if r1 == 0 {
   743  		if e1 != 0 {
   744  			err = error(e1)
   745  		} else {
   746  			err = syscall.EINVAL
   747  		}
   748  	}
   749  	return
   750  }
   751  
   752  func ConnectEx(fd Handle, sa Sockaddr, sendBuf *byte, sendDataLen uint32, bytesSent *uint32, overlapped *Overlapped) error {
   753  	err := LoadConnectEx()
   754  	if err != nil {
   755  		return errorspkg.New("failed to find ConnectEx: " + err.Error())
   756  	}
   757  	ptr, n, err := sa.sockaddr()
   758  	if err != nil {
   759  		return err
   760  	}
   761  	return connectEx(fd, ptr, n, sendBuf, sendDataLen, bytesSent, overlapped)
   762  }
   763  
   764  // Invented structures to support what package os expects.
   765  type Rusage struct {
   766  	CreationTime Filetime
   767  	ExitTime     Filetime
   768  	KernelTime   Filetime
   769  	UserTime     Filetime
   770  }
   771  
   772  type WaitStatus struct {
   773  	ExitCode uint32
   774  }
   775  
   776  func (w WaitStatus) Exited() bool { return true }
   777  
   778  func (w WaitStatus) ExitStatus() int { return int(w.ExitCode) }
   779  
   780  func (w WaitStatus) Signal() Signal { return -1 }
   781  
   782  func (w WaitStatus) CoreDump() bool { return false }
   783  
   784  func (w WaitStatus) Stopped() bool { return false }
   785  
   786  func (w WaitStatus) Continued() bool { return false }
   787  
   788  func (w WaitStatus) StopSignal() Signal { return -1 }
   789  
   790  func (w WaitStatus) Signaled() bool { return false }
   791  
   792  func (w WaitStatus) TrapCause() int { return -1 }
   793  
   794  // Timespec is an invented structure on Windows, but here for
   795  // consistency with the corresponding package for other operating systems.
   796  type Timespec struct {
   797  	Sec  int64
   798  	Nsec int64
   799  }
   800  
   801  func TimespecToNsec(ts Timespec) int64 { return int64(ts.Sec)*1e9 + int64(ts.Nsec) }
   802  
   803  func NsecToTimespec(nsec int64) (ts Timespec) {
   804  	ts.Sec = nsec / 1e9
   805  	ts.Nsec = nsec % 1e9
   806  	return
   807  }
   808  
   809  // TODO(brainman): fix all needed for net
   810  
   811  func Accept(fd Handle) (nfd Handle, sa Sockaddr, err error) { return 0, nil, syscall.EWINDOWS }
   812  func Recvfrom(fd Handle, p []byte, flags int) (n int, from Sockaddr, err error) {
   813  	return 0, nil, syscall.EWINDOWS
   814  }
   815  func Sendto(fd Handle, p []byte, flags int, to Sockaddr) (err error)       { return syscall.EWINDOWS }
   816  func SetsockoptTimeval(fd Handle, level, opt int, tv *Timeval) (err error) { return syscall.EWINDOWS }
   817  
   818  // The Linger struct is wrong but we only noticed after Go 1.
   819  // sysLinger is the real system call structure.
   820  
   821  // BUG(brainman): The definition of Linger is not appropriate for direct use
   822  // with Setsockopt and Getsockopt.
   823  // Use SetsockoptLinger instead.
   824  
   825  type Linger struct {
   826  	Onoff  int32
   827  	Linger int32
   828  }
   829  
   830  type sysLinger struct {
   831  	Onoff  uint16
   832  	Linger uint16
   833  }
   834  
   835  type IPMreq struct {
   836  	Multiaddr [4]byte /* in_addr */
   837  	Interface [4]byte /* in_addr */
   838  }
   839  
   840  type IPv6Mreq struct {
   841  	Multiaddr [16]byte /* in6_addr */
   842  	Interface uint32
   843  }
   844  
   845  func GetsockoptInt(fd Handle, level, opt int) (int, error) { return -1, syscall.EWINDOWS }
   846  
   847  func SetsockoptLinger(fd Handle, level, opt int, l *Linger) (err error) {
   848  	sys := sysLinger{Onoff: uint16(l.Onoff), Linger: uint16(l.Linger)}
   849  	return Setsockopt(fd, int32(level), int32(opt), (*byte)(unsafe.Pointer(&sys)), int32(unsafe.Sizeof(sys)))
   850  }
   851  
   852  func SetsockoptInet4Addr(fd Handle, level, opt int, value [4]byte) (err error) {
   853  	return Setsockopt(fd, int32(level), int32(opt), (*byte)(unsafe.Pointer(&value[0])), 4)
   854  }
   855  func SetsockoptIPMreq(fd Handle, level, opt int, mreq *IPMreq) (err error) {
   856  	return Setsockopt(fd, int32(level), int32(opt), (*byte)(unsafe.Pointer(mreq)), int32(unsafe.Sizeof(*mreq)))
   857  }
   858  func SetsockoptIPv6Mreq(fd Handle, level, opt int, mreq *IPv6Mreq) (err error) {
   859  	return syscall.EWINDOWS
   860  }
   861  
   862  func Getpid() (pid int) { return int(getCurrentProcessId()) }
   863  
   864  func FindFirstFile(name *uint16, data *Win32finddata) (handle Handle, err error) {
   865  	// NOTE(rsc): The Win32finddata struct is wrong for the system call:
   866  	// the two paths are each one uint16 short. Use the correct struct,
   867  	// a win32finddata1, and then copy the results out.
   868  	// There is no loss of expressivity here, because the final
   869  	// uint16, if it is used, is supposed to be a NUL, and Go doesn't need that.
   870  	// For Go 1.1, we might avoid the allocation of win32finddata1 here
   871  	// by adding a final Bug [2]uint16 field to the struct and then
   872  	// adjusting the fields in the result directly.
   873  	var data1 win32finddata1
   874  	handle, err = findFirstFile1(name, &data1)
   875  	if err == nil {
   876  		copyFindData(data, &data1)
   877  	}
   878  	return
   879  }
   880  
   881  func FindNextFile(handle Handle, data *Win32finddata) (err error) {
   882  	var data1 win32finddata1
   883  	err = findNextFile1(handle, &data1)
   884  	if err == nil {
   885  		copyFindData(data, &data1)
   886  	}
   887  	return
   888  }
   889  
   890  func getProcessEntry(pid int) (*ProcessEntry32, error) {
   891  	snapshot, err := CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0)
   892  	if err != nil {
   893  		return nil, err
   894  	}
   895  	defer CloseHandle(snapshot)
   896  	var procEntry ProcessEntry32
   897  	procEntry.Size = uint32(unsafe.Sizeof(procEntry))
   898  	if err = Process32First(snapshot, &procEntry); err != nil {
   899  		return nil, err
   900  	}
   901  	for {
   902  		if procEntry.ProcessID == uint32(pid) {
   903  			return &procEntry, nil
   904  		}
   905  		err = Process32Next(snapshot, &procEntry)
   906  		if err != nil {
   907  			return nil, err
   908  		}
   909  	}
   910  }
   911  
   912  func Getppid() (ppid int) {
   913  	pe, err := getProcessEntry(Getpid())
   914  	if err != nil {
   915  		return -1
   916  	}
   917  	return int(pe.ParentProcessID)
   918  }
   919  
   920  // TODO(brainman): fix all needed for os
   921  func Fchdir(fd Handle) (err error)             { return syscall.EWINDOWS }
   922  func Link(oldpath, newpath string) (err error) { return syscall.EWINDOWS }
   923  func Symlink(path, link string) (err error)    { return syscall.EWINDOWS }
   924  
   925  func Fchmod(fd Handle, mode uint32) (err error)        { return syscall.EWINDOWS }
   926  func Chown(path string, uid int, gid int) (err error)  { return syscall.EWINDOWS }
   927  func Lchown(path string, uid int, gid int) (err error) { return syscall.EWINDOWS }
   928  func Fchown(fd Handle, uid int, gid int) (err error)   { return syscall.EWINDOWS }
   929  
   930  func Getuid() (uid int)                  { return -1 }
   931  func Geteuid() (euid int)                { return -1 }
   932  func Getgid() (gid int)                  { return -1 }
   933  func Getegid() (egid int)                { return -1 }
   934  func Getgroups() (gids []int, err error) { return nil, syscall.EWINDOWS }
   935  
   936  type Signal int
   937  
   938  func (s Signal) Signal() {}
   939  
   940  func (s Signal) String() string {
   941  	if 0 <= s && int(s) < len(signals) {
   942  		str := signals[s]
   943  		if str != "" {
   944  			return str
   945  		}
   946  	}
   947  	return "signal " + itoa(int(s))
   948  }
   949  
   950  func LoadCreateSymbolicLink() error {
   951  	return procCreateSymbolicLinkW.Find()
   952  }
   953  
   954  // Readlink returns the destination of the named symbolic link.
   955  func Readlink(path string, buf []byte) (n int, err error) {
   956  	fd, err := CreateFile(StringToUTF16Ptr(path), GENERIC_READ, 0, nil, OPEN_EXISTING,
   957  		FILE_FLAG_OPEN_REPARSE_POINT|FILE_FLAG_BACKUP_SEMANTICS, 0)
   958  	if err != nil {
   959  		return -1, err
   960  	}
   961  	defer CloseHandle(fd)
   962  
   963  	rdbbuf := make([]byte, MAXIMUM_REPARSE_DATA_BUFFER_SIZE)
   964  	var bytesReturned uint32
   965  	err = DeviceIoControl(fd, FSCTL_GET_REPARSE_POINT, nil, 0, &rdbbuf[0], uint32(len(rdbbuf)), &bytesReturned, nil)
   966  	if err != nil {
   967  		return -1, err
   968  	}
   969  
   970  	rdb := (*reparseDataBuffer)(unsafe.Pointer(&rdbbuf[0]))
   971  	var s string
   972  	switch rdb.ReparseTag {
   973  	case IO_REPARSE_TAG_SYMLINK:
   974  		data := (*symbolicLinkReparseBuffer)(unsafe.Pointer(&rdb.reparseBuffer))
   975  		p := (*[0xffff]uint16)(unsafe.Pointer(&data.PathBuffer[0]))
   976  		s = UTF16ToString(p[data.PrintNameOffset/2 : (data.PrintNameLength-data.PrintNameOffset)/2])
   977  	case IO_REPARSE_TAG_MOUNT_POINT:
   978  		data := (*mountPointReparseBuffer)(unsafe.Pointer(&rdb.reparseBuffer))
   979  		p := (*[0xffff]uint16)(unsafe.Pointer(&data.PathBuffer[0]))
   980  		s = UTF16ToString(p[data.PrintNameOffset/2 : (data.PrintNameLength-data.PrintNameOffset)/2])
   981  	default:
   982  		// the path is not a symlink or junction but another type of reparse
   983  		// point
   984  		return -1, syscall.ENOENT
   985  	}
   986  	n = copy(buf, []byte(s))
   987  
   988  	return n, nil
   989  }