===================================================================
RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/tmux/tty.c,v
retrieving revision 1.265
retrieving revision 1.266
diff -c -r1.265 -r1.266
*** src/usr.bin/tmux/tty.c	2017/04/18 21:41:42	1.265
--- src/usr.bin/tmux/tty.c	2017/04/19 06:52:27	1.266
***************
*** 1,4 ****
! /* $OpenBSD: tty.c,v 1.265 2017/04/18 21:41:42 nicm Exp $ */
  
  /*
   * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
--- 1,4 ----
! /* $OpenBSD: tty.c,v 1.266 2017/04/19 06:52:27 nicm Exp $ */
  
  /*
   * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
***************
*** 79,84 ****
--- 79,88 ----
  #define tty_pane_full_width(tty, ctx) \
  	((ctx)->xoff == 0 && screen_size_x((ctx)->wp->screen) >= (tty)->sx)
  
+ #define TTY_BLOCK_INTERVAL (100000 /* 100 milliseconds */)
+ #define TTY_BLOCK_START(tty) (1 + ((tty)->sx * (tty)->sy) * 8)
+ #define TTY_BLOCK_STOP(tty) (1 + ((tty)->sx * (tty)->sy) / 8)
+ 
  void
  tty_create_log(void)
  {
***************
*** 172,177 ****
--- 176,226 ----
  }
  
  static void
+ tty_timer_callback(__unused int fd, __unused short events, void *data)
+ {
+ 	struct tty	*tty = data;
+ 	struct client	*c = tty->client;
+ 	struct timeval	 tv = { .tv_usec = TTY_BLOCK_INTERVAL };
+ 
+ 	log_debug("%s: %zu discarded", c->name, tty->discarded);
+ 
+ 	c->flags |= CLIENT_REDRAW;
+ 	c->discarded += tty->discarded;
+ 
+ 	if (tty->discarded < TTY_BLOCK_STOP(tty)) {
+ 		tty->flags &= ~TTY_BLOCK;
+ 		tty_invalidate(tty);
+ 		return;
+ 	}
+ 	tty->discarded = 0;
+ 	evtimer_add(&tty->timer, &tv);
+ }
+ 
+ static int
+ tty_block_maybe(struct tty *tty)
+ {
+ 	struct client	*c = tty->client;
+ 	size_t		 size = EVBUFFER_LENGTH(tty->out);
+ 	struct timeval	 tv = { .tv_usec = TTY_BLOCK_INTERVAL };
+ 
+ 	if (size < TTY_BLOCK_START(tty))
+ 		return (0);
+ 
+ 	if (tty->flags & TTY_BLOCK)
+ 		return (1);
+ 	tty->flags |= TTY_BLOCK;
+ 
+ 	log_debug("%s: can't keep up, %zu discarded", c->name, size);
+ 
+ 	evbuffer_drain(tty->out, size);
+ 	c->discarded += size;
+ 
+ 	tty->discarded = 0;
+ 	evtimer_add(&tty->timer, &tv);
+ 	return (1);
+ }
+ 
+ static void
  tty_write_callback(__unused int fd, __unused short events, void *data)
  {
  	struct tty	*tty = data;
***************
*** 184,189 ****
--- 233,241 ----
  		return;
  	log_debug("%s: wrote %d bytes (of %zu)", c->name, nwrite, size);
  
+ 	if (tty_block_maybe(tty))
+ 		return;
+ 
  	if (EVBUFFER_LENGTH(tty->out) != 0)
  		event_add(&tty->event_out, NULL);
  }
***************
*** 198,204 ****
  	}
  	tty->flags |= TTY_OPENED;
  
! 	tty->flags &= ~(TTY_NOCURSOR|TTY_FREEZE);
  
  	event_set(&tty->event_in, tty->fd, EV_PERSIST|EV_READ,
  	    tty_read_callback, tty);
--- 250,256 ----
  	}
  	tty->flags |= TTY_OPENED;
  
! 	tty->flags &= ~(TTY_NOCURSOR|TTY_FREEZE|TTY_BLOCK|TTY_TIMER);
  
  	event_set(&tty->event_in, tty->fd, EV_PERSIST|EV_READ,
  	    tty_read_callback, tty);
***************
*** 207,212 ****
--- 259,266 ----
  	event_set(&tty->event_out, tty->fd, EV_WRITE, tty_write_callback, tty);
  	tty->out = evbuffer_new();
  
+ 	evtimer_set(&tty->timer, tty_timer_callback, tty);
+ 
  	tty_start_tty(tty);
  
  	tty_keys_build(tty);
***************
*** 273,278 ****
--- 327,335 ----
  		return;
  	tty->flags &= ~TTY_STARTED;
  
+ 	event_del(&tty->timer);
+ 	tty->flags &= ~TTY_BLOCK;
+ 
  	event_del(&tty->event_in);
  	event_del(&tty->event_out);
  
***************
*** 425,433 ****
  {
  	struct client	*c = tty->client;
  
  	evbuffer_add(tty->out, buf, len);
  	log_debug("%s: %.*s", c->name, (int)len, (const char *)buf);
! 	tty->written += len;
  
  	if (tty_log_fd != -1)
  		write(tty_log_fd, buf, len);
--- 482,495 ----
  {
  	struct client	*c = tty->client;
  
+ 	if (tty->flags & TTY_BLOCK) {
+ 		tty->discarded += len;
+ 		return;
+ 	}
+ 
  	evbuffer_add(tty->out, buf, len);
  	log_debug("%s: %.*s", c->name, (int)len, (const char *)buf);
! 	c->written += len;
  
  	if (tty_log_fd != -1)
  		write(tty_log_fd, buf, len);