Some applications like vi(1) and tmux until 10 minutes or so ago, do not

redraw on SIGWINCH if the size returns to the original size between the
original SIGWINCH and when they get around to calling TIOCGWINSZ. So use
the existing resize timer to introduce a small delay between the two
resizes.

2 files changed, 44 insertions, 22 deletions

diff --git a/server-client.c b/server-client.c
index 15b0d2dc..e8faedc7 100644
--- a/server-client.c
+++ b/server-client.c
@@ -1038,6 +1038,44 @@ server_client_loop(void)
 	}
 }
 
+/* Check if we need to force a resize. */
+static int
+server_client_resize_force(struct window_pane *wp)
+{
+	struct timeval	tv = { .tv_usec = 100000 };
+	struct winsize	ws;
+
+	/*
+	 * If we are resizing to the same size as when we entered the loop
+	 * (that is, to the same size the application currently thinks it is),
+	 * tmux may have gone through several resizes internally and thrown
+	 * away parts of the screen. So we need the application to actually
+	 * redraw even though its final size has not changed.
+	 */
+
+	if (wp->flags & PANE_RESIZEFORCE) {
+		wp->flags &= ~PANE_RESIZEFORCE;
+		return (0);
+	}
+
+	if (wp->sx != wp->osx ||
+	    wp->sy != wp->osy ||
+	    wp->sx <= 1 ||
+	    wp->sy <= 1)
+		return (0);
+
+	memset(&ws, 0, sizeof ws);
+	ws.ws_col = wp->sx;
+	ws.ws_row = wp->sy - 1;
+	if (ioctl(wp->fd, TIOCSWINSZ, &ws) == -1)
+		fatal("ioctl failed");
+	log_debug("%s: %%%u forcing resize", __func__, wp->id);
+
+	evtimer_add(&wp->resize_timer, &tv);
+	wp->flags |= PANE_RESIZEFORCE;
+	return (1);
+}
+
 /* Resize timer event. */
 static void
 server_client_resize_event(__unused int fd, __unused short events, void *data)
@@ -1049,25 +1087,8 @@ server_client_resize_event(__unused int fd, __unused short events, void *data)
 
 	if (!(wp->flags & PANE_RESIZE))
 		return;
-
-	/*
-	 * If we are resizing to the same size as when we entered the loop
-	 * (that is, to the same size the application currently thinks it is),
-	 * tmux may have gone through several resizes internally and thrown
-	 * away parts of the screen. So we need the application to actually
-	 * redraw even though its final size has not changed.
-	 */
-	if (wp->sx == wp->osx &&
-	    wp->sy == wp->osy &&
-	    wp->sx > 1 &&
-	    wp->sy > 1) {
-		memset(&ws, 0, sizeof ws);
-		ws.ws_col = wp->sx - 1;
-		ws.ws_row = wp->sy - 1;
-		if (ioctl(wp->fd, TIOCSWINSZ, &ws) == -1)
-			fatal("ioctl failed");
-		log_debug("%s: %%%u forcing resize", __func__, wp->id);
-	}
+	if (server_client_resize_force(wp))
+		return;
 
 	memset(&ws, 0, sizeof ws);
 	ws.ws_col = wp->sx;
diff --git a/tmux.h b/tmux.h
index 79ae8ddc..b47a6911 100644
--- a/tmux.h
+++ b/tmux.h
@@ -756,9 +756,10 @@ struct window_pane {
 #define PANE_DROP 0x2
 #define PANE_FOCUSED 0x4
 #define PANE_RESIZE 0x8
-#define PANE_FOCUSPUSH 0x10
-#define PANE_INPUTOFF 0x20
-#define PANE_CHANGED 0x40
+#define PANE_RESIZEFORCE 0x10
+#define PANE_FOCUSPUSH 0x20
+#define PANE_INPUTOFF 0x40
+#define PANE_CHANGED 0x80
 
 	int		 argc;
 	char	       **argv;