blob: 8e3c99171bff45e784f95e5b8c57c7db80d39955 [file] [log] [blame]
//go:build windows && !appengine
// +build windows,!appengine
package isatty
import (
"errors"
"strings"
"syscall"
"unicode/utf16"
"unsafe"
)
const (
objectNameInfo uintptr = 1
fileNameInfo = 2
fileTypePipe = 3
)
var (
kernel32 = syscall.NewLazyDLL("kernel32.dll")
ntdll = syscall.NewLazyDLL("ntdll.dll")
procGetConsoleMode = kernel32.NewProc("GetConsoleMode")
procGetFileInformationByHandleEx = kernel32.NewProc("GetFileInformationByHandleEx")
procGetFileType = kernel32.NewProc("GetFileType")
procNtQueryObject = ntdll.NewProc("NtQueryObject")
)
func init() {
// Check if GetFileInformationByHandleEx is available.
if procGetFileInformationByHandleEx.Find() != nil {
procGetFileInformationByHandleEx = nil
}
}
// IsTerminal return true if the file descriptor is terminal.
func IsTerminal(fd uintptr) bool {
var st uint32
r, _, e := syscall.Syscall(procGetConsoleMode.Addr(), 2, fd, uintptr(unsafe.Pointer(&st)), 0)
return r != 0 && e == 0
}
// Check pipe name is used for cygwin/msys2 pty.
// Cygwin/MSYS2 PTY has a name like:
// \{cygwin,msys}-XXXXXXXXXXXXXXXX-ptyN-{from,to}-master
func isCygwinPipeName(name string) bool {
token := strings.Split(name, "-")
if len(token) < 5 {
return false
}
if token[0] != `\msys` &&
token[0] != `\cygwin` &&
token[0] != `\Device\NamedPipe\msys` &&
token[0] != `\Device\NamedPipe\cygwin` {
return false
}
if token[1] == "" {
return false
}
if !strings.HasPrefix(token[2], "pty") {
return false
}
if token[3] != `from` && token[3] != `to` {
return false
}
if token[4] != "master" {
return false
}
return true
}
// getFileNameByHandle use the undocomented ntdll NtQueryObject to get file full name from file handler
// since GetFileInformationByHandleEx is not available under windows Vista and still some old fashion
// guys are using Windows XP, this is a workaround for those guys, it will also work on system from
// Windows vista to 10
// see https://stackoverflow.com/a/18792477 for details
func getFileNameByHandle(fd uintptr) (string, error) {
if procNtQueryObject == nil {
return "", errors.New("ntdll.dll: NtQueryObject not supported")
}
var buf [4 + syscall.MAX_PATH]uint16
var result int
r, _, e := syscall.Syscall6(procNtQueryObject.Addr(), 5,
fd, objectNameInfo, uintptr(unsafe.Pointer(&buf)), uintptr(2*len(buf)), uintptr(unsafe.Pointer(&result)), 0)
if r != 0 {
return "", e
}
return string(utf16.Decode(buf[4 : 4+buf[0]/2])), nil
}
// IsCygwinTerminal() return true if the file descriptor is a cygwin or msys2
// terminal.
func IsCygwinTerminal(fd uintptr) bool {
if procGetFileInformationByHandleEx == nil {
name, err := getFileNameByHandle(fd)
if err != nil {
return false
}
return isCygwinPipeName(name)
}
// Cygwin/msys's pty is a pipe.
ft, _, e := syscall.Syscall(procGetFileType.Addr(), 1, fd, 0, 0)
if ft != fileTypePipe || e != 0 {
return false
}
var buf [2 + syscall.MAX_PATH]uint16
r, _, e := syscall.Syscall6(procGetFileInformationByHandleEx.Addr(),
4, fd, fileNameInfo, uintptr(unsafe.Pointer(&buf)),
uintptr(len(buf)*2), 0, 0)
if r == 0 || e != 0 {
return false
}
l := *(*uint32)(unsafe.Pointer(&buf))
return isCygwinPipeName(string(utf16.Decode(buf[2 : 2+l/2])))
}