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-rw-r--r--vendor/github.com/peterh/liner/output.go79
1 files changed, 79 insertions, 0 deletions
diff --git a/vendor/github.com/peterh/liner/output.go b/vendor/github.com/peterh/liner/output.go
new file mode 100644
index 000000000..6d83d4ebf
--- /dev/null
+++ b/vendor/github.com/peterh/liner/output.go
@@ -0,0 +1,79 @@
+// +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")
+}
+
+func (s *State) moveUp(lines int) {
+ fmt.Printf("\x1b[%dA", lines)
+}
+
+func (s *State) moveDown(lines int) {
+ fmt.Printf("\x1b[%dB", lines)
+}
+
+func (s *State) emitNewLine() {
+ fmt.Print("\n")
+}
+
+type winSize struct {
+ row, col uint16
+ xpixel, ypixel uint16
+}
+
+func (s *State) getColumns() bool {
+ var ws winSize
+ ok, _, _ := syscall.Syscall(syscall.SYS_IOCTL, uintptr(syscall.Stdout),
+ syscall.TIOCGWINSZ, uintptr(unsafe.Pointer(&ws)))
+ if int(ok) < 0 {
+ return false
+ }
+ s.columns = int(ws.col)
+ if cursorColumn && s.columns > 1 {
+ s.columns--
+ }
+ return true
+}
+
+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
+}