vendor/github.com/mattn/go-isatty/isatty_windows.go

   1 // +build windows
   2 // +build !appengine
   3
   4 package isatty
   5
   6 import (
   7         "strings"
   8         "syscall"
   9         "unicode/utf16"
  10         "unsafe"
  11 )
  12
  13 const (
  14         fileNameInfo uintptr = 2
  15         fileTypePipe         = 3
  16 )
  17
  18 var (
  19         kernel32                         = syscall.NewLazyDLL("kernel32.dll")
  20         procGetConsoleMode               = kernel32.NewProc("GetConsoleMode")
  21         procGetFileInformationByHandleEx = kernel32.NewProc("GetFileInformationByHandleEx")
  22         procGetFileType                  = kernel32.NewProc("GetFileType")
  23 )
  24
  25 func init() {
  26         // Check if GetFileInformationByHandleEx is available.
  27         if procGetFileInformationByHandleEx.Find() != nil {
  28                 procGetFileInformationByHandleEx = nil
  29         }
  30 }
  31
  32 // IsTerminal return true if the file descriptor is terminal.
  33 func IsTerminal(fd uintptr) bool {
  34         var st uint32
  35         r, _, e := syscall.Syscall(procGetConsoleMode.Addr(), 2, fd, uintptr(unsafe.Pointer(&st)), 0)
  36         return r != 0 && e == 0
  37 }
  38
  39 // Check pipe name is used for cygwin/msys2 pty.
  40 // Cygwin/MSYS2 PTY has a name like:
  41 //   \{cygwin,msys}-XXXXXXXXXXXXXXXX-ptyN-{from,to}-master
  42 func isCygwinPipeName(name string) bool {
  43         token := strings.Split(name, "-")
  44         if len(token) < 5 {
  45                 return false
  46         }
  47
  48         if token[0] != `\msys` && token[0] != `\cygwin` {
  49                 return false
  50         }
  51
  52         if token[1] == "" {
  53                 return false
  54         }
  55
  56         if !strings.HasPrefix(token[2], "pty") {
  57                 return false
  58         }
  59
  60         if token[3] != `from` && token[3] != `to` {
  61                 return false
  62         }
  63
  64         if token[4] != "master" {
  65                 return false
  66         }
  67
  68         return true
  69 }
  70
  71 // IsCygwinTerminal() return true if the file descriptor is a cygwin or msys2
  72 // terminal.
  73 func IsCygwinTerminal(fd uintptr) bool {
  74         if procGetFileInformationByHandleEx == nil {
  75                 return false
  76         }
  77
  78         // Cygwin/msys's pty is a pipe.
  79         ft, _, e := syscall.Syscall(procGetFileType.Addr(), 1, fd, 0, 0)
  80         if ft != fileTypePipe || e != 0 {
  81                 return false
  82         }
  83
  84         var buf [2 + syscall.MAX_PATH]uint16
  85         r, _, e := syscall.Syscall6(procGetFileInformationByHandleEx.Addr(),
  86                 4, fd, fileNameInfo, uintptr(unsafe.Pointer(&buf)),
  87                 uintptr(len(buf)*2), 0, 0)
  88         if r == 0 || e != 0 {
  89                 return false
  90         }
  91
  92         l := *(*uint32)(unsafe.Pointer(&buf))
  93         return isCygwinPipeName(string(utf16.Decode(buf[2 : 2+l/2])))
  94 }