Handle more signals without breaking terminal

cui/cui.go

@@ -57,15 +57,25 @@ func moveCursorToward(dir string, amount int) {
 }
 
 func Exit() {
+	CleanupTerm()
+	os.Exit(0)
+}
+
+func InitTerm() {
+	SetCharMode()
+	Tput("rmam")  // turn off line wrapping
+	Tput("smcup") // use alternate screen
+}
+
+func CleanupTerm() {
 	moveCursorToward("down", 500)
 	moveCursorToward("right", 500)
 	SetLineMode()
 
 	fmt.Print("\n")
 	fmt.Print("\033[?25h")
-	Tput("smam") // turn off line wrap
-	Tput("rmcup") // use alternate screen
-	os.Exit(0)
+	Tput("smam")  // turn on line wrap
+	Tput("rmcup") // stop using alternate screen
 }
 
 func Clear(dir string) {

main.go

@@ -112,7 +112,7 @@ func loadConfig() error {
 		if lowerkey == "configlocation" {
 			// The config defaults to the home folder.
 			// Users cannot really edit this value. But
-      // a compile time override is available.
+			// a compile time override is available.
 			// It is still stored in the ini and as a part
 			// of the options map.
 			continue
@@ -140,7 +140,6 @@ func loadConfig() error {
 
 func initClient() error {
 	bombadillo = MakeClient("  ((( Bombadillo )))  ")
-	cui.SetCharMode()
 	err := loadConfig()
 	if bombadillo.Options["tlscertificate"] != "" && bombadillo.Options["tlskey"] != "" {
 		bombadillo.Certs.LoadCertificate(bombadillo.Options["tlscertificate"], bombadillo.Options["tlskey"])
@@ -148,16 +147,22 @@ func initClient() error {
 	return err
 }
 
-// In the event of SIGCONT, ensure the display is shown correctly.  Accepts a
-// signal, blocking until it is received. Once not blocked, corrects terminal
-// display settings. Loops indefinitely, does not return.
-func handleSIGCONT(c <-chan os.Signal) {
-	for {
-		<-c
-		cui.Tput("rmam")  // turn off line wrapping
-		cui.Tput("smcup") // use alternate screen
-		cui.SetCharMode()
+// In the event of specific signals, ensure the display is shown correctly.
+// Accepts a signal, blocking until it is received.  Once not blocked, corrects
+// terminal display settings. Loops indefinitely, does not return.
+func handleSignals(c <-chan os.Signal) {
+	switch <-c {
+	case syscall.SIGTSTP:
+		cui.CleanupTerm()
+		//TODO: getting stuck here
+		// SIGSTOP seems to be the right signal, but the process
+		// does not recover?
+		syscall.Kill(syscall.Getpid(), syscall.SIGSTOP)
+	case syscall.SIGCONT:
+		cui.InitTerm()
 		bombadillo.Draw()
+	case syscall.SIGINT:
+		cui.Exit()
 	}
 }
 
@@ -174,8 +179,7 @@ func main() {
 	// So that we can open files from gemini
 	mc = mailcap.NewMailcap()
 
-	cui.Tput("rmam")  // turn off line wrapping
-	cui.Tput("smcup") // use alternate screen
+	cui.InitTerm()
 	defer cui.Exit()
 	err := initClient()
 	if err != nil {
@@ -183,10 +187,10 @@ func main() {
 		panic(err)
 	}
 
-	// watch for SIGCONT, send it to be handled
+	// watch for signals, send them to be handled
 	c := make(chan os.Signal, 1)
-	signal.Notify(c, syscall.SIGCONT)
-	go handleSIGCONT(c)
+	signal.Notify(c, syscall.SIGTSTP, syscall.SIGCONT, syscall.SIGINT)
+	go handleSignals(c)
 
 	// Start polling for terminal size changes
 	go bombadillo.GetSize()