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/* $OpenBSD: xxflush.c,v 1.3 1997/02/25 00:05:17 downsj Exp $ */
/* $NetBSD: xxflush.c,v 1.3 1995/09/28 10:36:05 tls Exp $ */
/*
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Edward Wang at The University of California, Berkeley.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
#if 0
static char sccsid[] = "@(#)xxflush.c 8.1 (Berkeley) 6/6/93";
#else
static char rcsid[] = "$OpenBSD: xxflush.c,v 1.3 1997/02/25 00:05:17 downsj Exp $";
#endif
#endif /* not lint */
#include "ww.h"
#include "xx.h"
#include "tt.h"
xxflush(intr)
register intr;
{
register struct xx *xp, *xq;
for (xp = xx_head; xp != 0 && !(intr && wwinterrupt()); xp = xq) {
switch (xp->cmd) {
case xc_move:
if (xp->link == 0)
(*tt.tt_move)(xp->arg0, xp->arg1);
break;
case xc_scroll:
xxflush_scroll(xp);
break;
case xc_inschar:
(*tt.tt_move)(xp->arg0, xp->arg1);
tt.tt_nmodes = xp->arg3;
(*tt.tt_inschar)(xp->arg2);
break;
case xc_insspace:
(*tt.tt_move)(xp->arg0, xp->arg1);
(*tt.tt_insspace)(xp->arg2);
break;
case xc_delchar:
(*tt.tt_move)(xp->arg0, xp->arg1);
(*tt.tt_delchar)(xp->arg2);
break;
case xc_clear:
(*tt.tt_clear)();
break;
case xc_clreos:
(*tt.tt_move)(xp->arg0, xp->arg1);
(*tt.tt_clreos)();
break;
case xc_clreol:
(*tt.tt_move)(xp->arg0, xp->arg1);
(*tt.tt_clreol)();
break;
case xc_write:
(*tt.tt_move)(xp->arg0, xp->arg1);
tt.tt_nmodes = xp->arg3;
(*tt.tt_write)(xp->buf, xp->arg2);
break;
}
xq = xp->link;
xxfree(xp);
}
if ((xx_head = xp) == 0) {
xx_tail = 0;
xxbufp = xxbuf;
}
ttflush();
}
xxflush_scroll(xp)
register struct xx *xp;
{
register struct xx *xq;
top:
if (xp->arg0 == 0)
return;
/*
* We handle retain (da and db) by putting the burden on scrolling up,
* which is the less common operation. It must ensure that
* text is not pushed below the screen, so scrolling down doesn't
* have to worry about it.
*
* Try scrolling region (or scrolling the whole screen) first.
* Can we assume "sr" doesn't push text below the screen
* so we don't have to worry about retain below?
* What about scrolling down with a newline? It probably does
* push text above (with da). Scrolling up would then have
* to take care of that.
* It's easy to be fool proof, but that slows things down.
* The current solution is to disallow tt_scroll_up if da or db is true
* but cs (scrolling region) is not. Again, we sacrifice scrolling
* up in favor of scrolling down. The idea is having scrolling regions
* probably means we can scroll (even the whole screen) with impunity.
* This lets us work efficiently on simple terminals (use newline
* on the bottom to scroll), on any terminal without retain, and
* on vt100 style scrolling regions (I think).
*/
if (xp->arg0 > 0) {
if ((xq = xp->link) != 0 && xq->cmd == xc_scroll &&
xp->arg2 == xq->arg2 && xq->arg0 < 0) {
if (xp->arg1 < xq->arg1) {
if (xp->arg2 - xp->arg0 <= xq->arg1) {
xq->arg0 = xp->arg0;
xq->arg1 = xp->arg1;
xq->arg2 = xp->arg2;
return;
}
xp->arg2 = xq->arg1 + xp->arg0;
xq->arg0 += xp->arg0;
xq->arg1 = xp->arg2;
if (xq->arg0 > 0)
xq->arg1 -= xq->arg0;
goto top;
} else {
if (xp->arg1 - xq->arg0 >= xp->arg2)
return;
xq->arg2 = xp->arg1 - xq->arg0;
xp->arg0 += xq->arg0;
xp->arg1 = xq->arg2;
if (xp->arg0 < 0)
xp->arg1 += xp->arg0;
goto top;
}
}
if (xp->arg0 > xp->arg2 - xp->arg1)
xp->arg0 = xp->arg2 - xp->arg1;
if (tt.tt_scroll_down) {
if (tt.tt_scroll_top != xp->arg1 ||
tt.tt_scroll_bot != xp->arg2 - 1) {
if (tt.tt_setscroll == 0)
goto down;
(*tt.tt_setscroll)(xp->arg1, xp->arg2 - 1);
}
tt.tt_scroll_down(xp->arg0);
} else {
down:
(*tt.tt_move)(xp->arg1, 0);
(*tt.tt_delline)(xp->arg0);
if (xp->arg2 < tt.tt_nrow) {
(*tt.tt_move)(xp->arg2 - xp->arg0, 0);
(*tt.tt_insline)(xp->arg0);
}
}
} else {
xp->arg0 = - xp->arg0;
if (xp->arg0 > xp->arg2 - xp->arg1)
xp->arg0 = xp->arg2 - xp->arg1;
if (tt.tt_scroll_up) {
if (tt.tt_scroll_top != xp->arg1 ||
tt.tt_scroll_bot != xp->arg2 - 1) {
if (tt.tt_setscroll == 0)
goto up;
(*tt.tt_setscroll)(xp->arg1, xp->arg2 - 1);
}
tt.tt_scroll_up(xp->arg0);
} else {
up:
if (tt.tt_retain || xp->arg2 != tt.tt_nrow) {
(*tt.tt_move)(xp->arg2 - xp->arg0, 0);
(*tt.tt_delline)(xp->arg0);
}
(*tt.tt_move)(xp->arg1, 0);
(*tt.tt_insline)(xp->arg0);
}
}
}
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