podman

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