forked from mirror/ledisdb
64 lines
1.2 KiB
Go
64 lines
1.2 KiB
Go
|
// +build linux darwin openbsd freebsd netbsd
|
||
|
|
|
||
|
|
package liner
|
||
|
|
|
||
|
|
import (
|
||
|
|
"fmt"
|
||
|
|
"os"
|
||
|
|
"strings"
|
||
|
|
"syscall"
|
||
|
|
"unsafe"
|
||
|
|
)
|
||
|
|
|
||
|
|
func (s *State) cursorPos(x int) {
|
||
|
|
if s.useCHA {
|
||
|
|
// 'G' is "Cursor Character Absolute (CHA)"
|
||
|
|
fmt.Printf("\x1b[%dG", x+1)
|
||
|
|
} else {
|
||
|
|
// 'C' is "Cursor Forward (CUF)"
|
||
|
|
fmt.Print("\r")
|
||
|
|
if x > 0 {
|
||
|
|
fmt.Printf("\x1b[%dC", x)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
func (s *State) eraseLine() {
|
||
|
|
fmt.Print("\x1b[0K")
|
||
|
|
}
|
||
|
|
|
||
|
|
func (s *State) eraseScreen() {
|
||
|
|
fmt.Print("\x1b[H\x1b[2J")
|
||
|
|
}
|
||
|
|
|
||
|
|
type winSize struct {
|
||
|
|
row, col uint16
|
||
|
|
xpixel, ypixel uint16
|
||
|
|
}
|
||
|
|
|
||
|
|
func (s *State) getColumns() {
|
||
|
|
var ws winSize
|
||
|
|
ok, _, _ := syscall.Syscall(syscall.SYS_IOCTL, uintptr(syscall.Stdout),
|
||
|
|
syscall.TIOCGWINSZ, uintptr(unsafe.Pointer(&ws)))
|
||
|
|
if ok < 0 {
|
||
|
|
s.columns = 80
|
||
|
|
}
|
||
|
|
s.columns = int(ws.col)
|
||
|
|
}
|
||
|
|
|
||
|
|
func (s *State) checkOutput() {
|
||
|
|
// xterm is known to support CHA
|
||
|
|
if strings.Contains(strings.ToLower(os.Getenv("TERM")), "xterm") {
|
||
|
|
s.useCHA = true
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
// The test for functional ANSI CHA is unreliable (eg the Windows
|
||
|
|
// telnet command does not support reading the cursor position with
|
||
|
|
// an ANSI DSR request, despite setting TERM=ansi)
|
||
|
|
|
||
|
|
// Assume CHA isn't supported (which should be safe, although it
|
||
|
|
// does result in occasional visible cursor jitter)
|
||
|
|
s.useCHA = false
|
||
|
|
}
|