Sync OpenBSD patchset 1072:

Add a simple form of output rate limiting by counting the number of
certain C0 sequences (linefeeds, backspaces, carriage returns) and if it
exceeds a threshold (current default 50/millisecond), start to redraw
the pane every 100 milliseconds instead of making each change as it
comes. Two configuration options - c0-change-trigger and
c0-change-interval.

This makes tmux much more responsive under very fast output (for example
yes(1) or accidentally cat'ing a large file) but may not be perfect on
all terminals and connections - feedback very welcome, particularly
where this change has a negative rather than positive effect (making it
off by default is a possibility).

After much experimentation based originally on a request Robin Lee
Powell (which ended with a completely different solution), this idea
from discussion with Ailin Nemui.

1 files changed, 6 insertions, 1 deletions

diff --git a/tmux.h b/tmux.h
index dd3937ac..077200ae 100644
--- a/tmux.h
+++ b/tmux.h
@@ -807,6 +807,7 @@ struct window_pane {
 
 	int		 flags;
 #define PANE_REDRAW 0x1
+#define PANE_DROP 0x2
 
 	char		*cmd;
 	char		*shell;
@@ -815,6 +816,10 @@ struct window_pane {
 	pid_t		 pid;
 	char		 tty[TTY_NAME_MAX];
 
+	u_int		 changes;
+	struct event	 changes_timer;
+	u_int		 changes_redraw;
+
 	int		 fd;
 	struct bufferevent *event;
 
@@ -1959,6 +1964,7 @@ void		 window_destroy_panes(struct window *);
 struct window_pane *window_pane_find_by_id(u_int);
 struct window_pane *window_pane_create(struct window *, u_int, u_int, u_int);
 void		 window_pane_destroy(struct window_pane *);
+void		 window_pane_timer_start(struct window_pane *);
 int		 window_pane_spawn(struct window_pane *, const char *,
 		     const char *, const char *, struct environ *,
 		     struct termios *, char **);
@@ -1977,7 +1983,6 @@ int		 window_pane_visible(struct window_pane *);
 char		*window_pane_search(
 		     struct window_pane *, const char *, u_int *);
 char		*window_printable_flags(struct session *, struct winlink *);
-
 struct window_pane *window_pane_find_up(struct window_pane *);
 struct window_pane *window_pane_find_down(struct window_pane *);
 struct window_pane *window_pane_find_left(struct window_pane *);