whatcanGOwrong

go/pkg/mod/github.com/go-delve/liner@v1.2.3-0.20231231155935-4726ab1d7f62/output.go

@@ -0,0 +1,64 @@
+//go:build linux || darwin || openbsd || freebsd || netbsd || solaris
+// +build linux darwin openbsd freebsd netbsd solaris
+
+package liner
+
+import (
+	"fmt"
+	"os"
+	"strings"
+)
+
+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) 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
+}