forked from mirror/readline
71 lines
1.1 KiB
Go
71 lines
1.1 KiB
Go
// +build darwin dragonfly freebsd linux,!appengine netbsd openbsd
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package readline
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import (
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"os"
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"os/signal"
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"sync"
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"syscall"
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"unsafe"
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)
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type winsize struct {
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Row uint16
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Col uint16
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Xpixel uint16
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Ypixel uint16
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}
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// get width of the terminal
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func getWidth(stdoutFd int) int {
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ws := &winsize{}
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retCode, _, errno := syscall.Syscall(syscall.SYS_IOCTL,
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uintptr(stdoutFd),
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uintptr(syscall.TIOCGWINSZ),
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uintptr(unsafe.Pointer(ws)))
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if int(retCode) == -1 {
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_ = errno
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return -1
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}
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return int(ws.Col)
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}
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func GetScreenWidth() int {
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return getWidth(syscall.Stdout)
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}
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func DefaultIsTerminal() bool {
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return IsTerminal(syscall.Stdin) && IsTerminal(syscall.Stdout)
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}
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func GetStdin() int {
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return syscall.Stdin
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}
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// -----------------------------------------------------------------------------
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var (
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widthChange sync.Once
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widthChangeCallback func()
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)
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func DefaultOnWidthChanged(f func()) {
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widthChangeCallback = f
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widthChange.Do(func() {
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ch := make(chan os.Signal, 1)
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signal.Notify(ch, syscall.SIGWINCH)
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go func() {
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for {
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_, ok := <-ch
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if !ok {
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break
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}
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widthChangeCallback()
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}
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}()
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})
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}
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