initctl: fix remaining lingering artifacts in 'top' output

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

src/cgutil.c

@@ -728,13 +728,24 @@ int show_cgps(char *arg)
 
 static void cgtop(uev_t *w, void *arg, int events)
 {
+	static int first = 1;
 	int lines;
 
 	(void)w;
 	(void)events;
 
-	/* Move cursor to home instead of clearing screen to avoid flicker */
-	fputs("\e[H", stdout);
+	/* Re-probe screen size in case terminal was resized */
+	ttinit(1);
+
+	/* Clear screen on first run to remove any artifacts */
+	if (first) {
+		fputs("\e[?7l\e[2J\e[H", stdout);  /* Disable line wrap, clear, home */
+		first = 0;
+	} else {
+		/* Move cursor to home instead of clearing screen to avoid flicker */
+		fputs("\e[H", stdout);
+	}
+
 	lines = 0;
 	if (heading) {
 		print_header(" VmSIZE     RSS   VmLIB  %%MEM  %%CPU  GROUP");
@@ -749,6 +760,7 @@ static void cgtop(uev_t *w, void *arg, int events)
 
 static void cleanup(void)
 {
+	fputs("\e[?7h", stdout);	/* Re-enable line wrap */
 	ttcooked();
 	showcursor();
 	puts("");
@@ -799,6 +811,9 @@ int show_cgtop(char *arg)
 	if (!hcreate(ttrows + 25))
 		ERR(70, "failed creating hash table");
 
+	/* Ensure we have correct terminal size before starting */
+	ttinit(1);
+
 	sysinfo(&si);
 	total_ram = si.totalram * si.mem_unit;
 

src/initctl.c

@@ -1724,7 +1724,7 @@ int main(int argc, char *argv[])
 	}
 
 	if (interactive)
-		ttinit();
+		ttinit(0);
 
 	return cmd_parse(argc - optind, &argv[optind], command);
 }

src/util.c

@@ -687,7 +687,7 @@ int fistmpfs(char *dir)
  * Called by initctl, and by finit at boot and shutdown, to
  * (re)initialize the screen size for print() et al.
  */
-int ttinit(void)
+int ttinit(int probe_size)
 {
 	struct pollfd fd = { STDIN_FILENO, POLLIN, 0 };
 	struct winsize ws = { 0 };
@@ -707,6 +707,9 @@ int ttinit(void)
 		tcsetattr(STDERR_FILENO, TCSANOW, &tc);
 	}
 
+	if (probe_size)
+		goto fallback;
+
 	/* 1. Try TIOCWINSZ to query window size from kernel */
 	if (!ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws)) {
 		ttrows = ws.ws_row;

src/util.h

@@ -95,11 +95,11 @@ int   fismnt       (char *dir);
 int   fistmpfs     (char *dir);
 
 #ifdef HAVE_TERMIOS_H
-int     ttinit     (void);
+int     ttinit     (int probe_size);
 int     ttraw      (void);
 int     ttcooked   (void);
 #else
-#define ttinit()   ttcols
+#define ttinit(v)  ttcols
 #define ttraw()    0
 #define ttcooked() 0
 #endif