NetBSD/lib/libcurses/refresh.c
1997-07-22 07:36:20 +00:00

841 lines
23 KiB
C

/* $NetBSD: refresh.c,v 1.8 1997/07/22 07:36:59 mikel Exp $ */
/*
* Copyright (c) 1981, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* 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.
*/
#include <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)refresh.c 8.7 (Berkeley) 8/13/94";
#else
__RCSID("$NetBSD: refresh.c,v 1.8 1997/07/22 07:36:59 mikel Exp $");
#endif
#endif /* not lint */
#include <string.h>
#include "curses.h"
static int curwin;
static short ly, lx;
static void domvcur __P((int, int, int, int));
static int makech __P((WINDOW *, int));
static void quickch __P((WINDOW *));
static void scrolln __P((WINDOW *, int, int, int, int, int));
/*
* wrefresh --
* Make the current screen look like "win" over the area coverd by
* win.
*/
int
wrefresh(win)
register WINDOW *win;
{
register __LINE *wlp;
register int retval;
register short wy;
int dnum;
/* Initialize loop parameters. */
ly = curscr->cury;
lx = curscr->curx;
wy = 0;
curwin = (win == curscr);
if (!curwin)
for (wy = 0; wy < win->maxy; wy++) {
wlp = win->lines[wy];
if (wlp->flags & __ISDIRTY)
wlp->hash = __hash((char *)wlp->line,
win->maxx * __LDATASIZE);
}
if (win->flags & __CLEAROK || curscr->flags & __CLEAROK || curwin) {
if ((win->flags & __FULLWIN) || curscr->flags & __CLEAROK) {
tputs(CL, 0, __cputchar);
ly = 0;
lx = 0;
if (!curwin) {
curscr->flags &= ~__CLEAROK;
curscr->cury = 0;
curscr->curx = 0;
werase(curscr);
}
__touchwin(win);
}
win->flags &= ~__CLEAROK;
}
if (!CA) {
if (win->curx != 0)
putchar('\n');
if (!curwin)
werase(curscr);
}
#ifdef DEBUG
__CTRACE("wrefresh: (%0.2o): curwin = %d\n", win, curwin);
__CTRACE("wrefresh: \tfirstch\tlastch\n");
#endif
#ifndef NOQCH
if ((win->flags & __FULLWIN) && !curwin) {
/*
* Invoke quickch() only if more than a quarter of the lines
* in the window are dirty.
*/
for (wy = 0, dnum = 0; wy < win->maxy; wy++)
if (win->lines[wy]->flags & (__ISDIRTY | __FORCEPAINT))
dnum++;
if (!__noqch && dnum > (int) win->maxy / 4)
quickch(win);
}
#endif
#ifdef DEBUG
{ int i, j;
__CTRACE("#####################################\n");
for (i = 0; i < curscr->maxy; i++) {
__CTRACE("C: %d:", i);
__CTRACE(" 0x%x \n", curscr->lines[i]->hash);
for (j = 0; j < curscr->maxx; j++)
__CTRACE("%c",
curscr->lines[i]->line[j].ch);
__CTRACE("\n");
for (j = 0; j < curscr->maxx; j++)
__CTRACE("%x",
curscr->lines[i]->line[j].attr);
__CTRACE("\n");
__CTRACE("W: %d:", i);
__CTRACE(" 0x%x \n", win->lines[i]->hash);
__CTRACE(" 0x%x ", win->lines[i]->flags);
for (j = 0; j < win->maxx; j++)
__CTRACE("%c",
win->lines[i]->line[j].ch);
__CTRACE("\n");
for (j = 0; j < win->maxx; j++)
__CTRACE("%x",
win->lines[i]->line[j].attr);
__CTRACE("\n");
}
}
#endif /* DEBUG */
for (wy = 0; wy < win->maxy; wy++) {
#ifdef DEBUG
__CTRACE("%d\t%d\t%d\n",
wy, *win->lines[wy]->firstchp, *win->lines[wy]->lastchp);
#endif
if (!curwin)
curscr->lines[wy]->hash = win->lines[wy]->hash;
if (win->lines[wy]->flags & (__ISDIRTY | __FORCEPAINT)) {
if (makech(win, wy) == ERR)
return (ERR);
else {
if (*win->lines[wy]->firstchp >= win->ch_off)
*win->lines[wy]->firstchp = win->maxx +
win->ch_off;
if (*win->lines[wy]->lastchp < win->maxx +
win->ch_off)
*win->lines[wy]->lastchp = win->ch_off;
if (*win->lines[wy]->lastchp <
*win->lines[wy]->firstchp) {
#ifdef DEBUG
__CTRACE("wrefresh: line %d notdirty \n", wy);
#endif
win->lines[wy]->flags &= ~__ISDIRTY;
}
}
}
#ifdef DEBUG
__CTRACE("\t%d\t%d\n", *win->lines[wy]->firstchp,
*win->lines[wy]->lastchp);
#endif
}
#ifdef DEBUG
__CTRACE("refresh: ly=%d, lx=%d\n", ly, lx);
#endif
if (win == curscr)
domvcur(ly, lx, win->cury, win->curx);
else {
if (win->flags & __LEAVEOK) {
curscr->cury = ly;
curscr->curx = lx;
ly -= win->begy;
lx -= win->begx;
if (ly >= 0 && ly < win->maxy && lx >= 0 &&
lx < win->maxx) {
win->cury = ly;
win->curx = lx;
} else
win->cury = win->curx = 0;
} else {
domvcur(ly, lx, win->cury + win->begy,
win->curx + win->begx);
curscr->cury = win->cury + win->begy;
curscr->curx = win->curx + win->begx;
}
}
retval = OK;
(void)fflush(stdout);
return (retval);
}
/*
* makech --
* Make a change on the screen.
*/
static int
makech(win, wy)
register WINDOW *win;
int wy;
{
static __LDATA blank = {' ', 0};
__LDATA *nsp, *csp, *cp, *cep;
u_int force;
int clsp, nlsp; /* Last space in lines. */
int lch, wx, y;
char *ce;
#ifdef __GNUC__
nlsp = 0; /* XXX gcc -Wuninitialized */
#endif
/* Is the cursor still on the end of the last line? */
if (wy > 0 && win->lines[wy - 1]->flags & __ISPASTEOL) {
domvcur(ly, lx, ly + 1, 0);
ly++;
lx = 0;
}
wx = *win->lines[wy]->firstchp - win->ch_off;
if (wx < 0)
wx = 0;
else if (wx >= win->maxx)
return (OK);
lch = *win->lines[wy]->lastchp - win->ch_off;
if (lch < 0)
return (OK);
else if (lch >= (int) win->maxx)
lch = win->maxx - 1;
y = wy + win->begy;
if (curwin)
csp = &blank;
else
csp = &curscr->lines[wy + win->begy]->line[wx + win->begx];
nsp = &win->lines[wy]->line[wx];
force = win->lines[wy]->flags & __FORCEPAINT;
win->lines[wy]->flags &= ~__FORCEPAINT;
if (CE && !curwin) {
for (cp = &win->lines[wy]->line[win->maxx - 1];
cp->ch == ' ' && cp->attr == 0; cp--)
if (cp <= win->lines[wy]->line)
break;
nlsp = cp - win->lines[wy]->line;
}
if (!curwin)
ce = CE;
else
ce = NULL;
if (force) {
if (CM)
tputs(tgoto(CM, lx, ly), 0, __cputchar);
else {
tputs(HO, 0, __cputchar);
__mvcur(0, 0, ly, lx, 1);
}
}
while (wx <= lch) {
if (!force && memcmp(nsp, csp, sizeof(__LDATA)) == 0) {
if (wx <= lch) {
while (wx <= lch &&
memcmp(nsp, csp, sizeof(__LDATA)) == 0) {
nsp++;
if (!curwin)
++csp;
++wx;
}
continue;
}
break;
}
domvcur(ly, lx, y, wx + win->begx);
#ifdef DEBUG
__CTRACE("makech: 1: wx = %d, ly= %d, lx = %d, newy = %d, newx = %d, force =%d\n",
wx, ly, lx, y, wx + win->begx, force);
#endif
ly = y;
lx = wx + win->begx;
while ((force || memcmp(nsp, csp, sizeof(__LDATA)) != 0)
&& wx <= lch) {
if (ce != NULL &&
win->maxx + win->begx == curscr->maxx &&
wx >= nlsp && nsp->ch == ' ' && nsp->attr == 0) {
/* Check for clear to end-of-line. */
cep = &curscr->lines[wy]->line[win->maxx - 1];
while (cep->ch == ' ' && cep->attr == 0)
if (cep-- <= csp)
break;
clsp = cep - curscr->lines[wy]->line -
win->begx * __LDATASIZE;
#ifdef DEBUG
__CTRACE("makech: clsp = %d, nlsp = %d\n", clsp, nlsp);
#endif
if ((clsp - nlsp >= strlen(CE)
&& clsp < win->maxx * __LDATASIZE) ||
wy == win->maxy - 1) {
if (curscr->flags & __WSTANDOUT) {
tputs(SE, 0, __cputchar);
curscr->flags &= ~__WSTANDOUT;
}
tputs(CE, 0, __cputchar);
lx = wx + win->begx;
while (wx++ <= clsp) {
csp->ch = ' ';
csp->attr = 0;
csp++;
}
return (OK);
}
ce = NULL;
}
/*
* Enter/exit standout mode as appropriate.
* XXX
* Should use UC if SO/SE not available.
*/
if (nsp->attr & __STANDOUT) {
if (!(curscr->flags & __WSTANDOUT) &&
SO != NULL && SE != NULL) {
tputs(SO, 0, __cputchar);
curscr->flags |= __WSTANDOUT;
}
} else
if (curscr->flags & __WSTANDOUT &&
SE != NULL) {
tputs(SE, 0, __cputchar);
curscr->flags &= ~__WSTANDOUT;
}
wx++;
if (wx >= win->maxx && wy == win->maxy - 1 && !curwin)
if (win->flags & __SCROLLOK) {
if (curscr->flags & __WSTANDOUT
&& win->flags & __ENDLINE)
if (!MS) {
tputs(SE, 0,
__cputchar);
curscr->flags &=
~__WSTANDOUT;
}
if (!(win->flags & __SCROLLWIN)) {
if (!curwin) {
csp->attr = nsp->attr;
putchar(csp->ch = nsp->ch);
} else
putchar(nsp->ch);
}
if (wx + win->begx < curscr->maxx) {
domvcur(ly, wx + win->begx,
win->begy + win->maxy - 1,
win->begx + win->maxx - 1);
}
ly = win->begy + win->maxy - 1;
lx = win->begx + win->maxx - 1;
return (OK);
}
if (wx < win->maxx || wy < win->maxy - 1 ||
!(win->flags & __SCROLLWIN)) {
if (!curwin) {
csp->attr = nsp->attr;
putchar(csp->ch = nsp->ch);
csp++;
} else
putchar(nsp->ch);
}
#ifdef DEBUG
__CTRACE("makech: putchar(%c)\n", nsp->ch & 0177);
#endif
if (UC && (nsp->attr & __STANDOUT)) {
putchar('\b');
tputs(UC, 0, __cputchar);
}
nsp++;
#ifdef DEBUG
__CTRACE("makech: 2: wx = %d, lx = %d\n", wx, lx);
#endif
}
if (lx == wx + win->begx) /* If no change. */
break;
lx = wx + win->begx;
if (lx >= COLS && AM)
lx = COLS - 1;
else if (wx >= win->maxx) {
domvcur(ly, lx, ly, win->maxx + win->begx - 1);
lx = win->maxx + win->begx - 1;
}
#ifdef DEBUG
__CTRACE("makech: 3: wx = %d, lx = %d\n", wx, lx);
#endif
}
/* Don't leave the screen in standout mode. */
if (curscr->flags & __WSTANDOUT) {
tputs(SE, 0, __cputchar);
curscr->flags &= ~__WSTANDOUT;
}
return (OK);
}
/*
* domvcur --
* Do a mvcur, leaving standout mode if necessary.
*/
static void
domvcur(oy, ox, ny, nx)
int oy, ox, ny, nx;
{
if (curscr->flags & __WSTANDOUT && !MS) {
tputs(SE, 0, __cputchar);
curscr->flags &= ~__WSTANDOUT;
}
__mvcur(oy, ox, ny, nx, 1);
}
/*
* Quickch() attempts to detect a pattern in the change of the window
* in order to optimize the change, e.g., scroll n lines as opposed to
* repainting the screen line by line.
*/
static void
quickch(win)
WINDOW *win;
{
#define THRESH (int) win->maxy / 4
register __LINE *clp, *tmp1, *tmp2;
register int bsize, curs, curw, starts, startw, i, j;
int n, target, cur_period, bot, top, sc_region;
__LDATA buf[1024];
u_int blank_hash;
#ifdef __GNUC__
curs = curw = starts = startw = 0; /* XXX gcc -Wuninitialized */
#endif
/*
* Find how many lines from the top of the screen are unchanged.
*/
for (top = 0; top < win->maxy; top++)
if (win->lines[top]->flags & __FORCEPAINT ||
win->lines[top]->hash != curscr->lines[top]->hash
|| memcmp(win->lines[top]->line,
curscr->lines[top]->line,
win->maxx * __LDATASIZE) != 0)
break;
else
win->lines[top]->flags &= ~__ISDIRTY;
/*
* Find how many lines from bottom of screen are unchanged.
*/
for (bot = win->maxy - 1; bot >= 0; bot--)
if (win->lines[bot]->flags & __FORCEPAINT ||
win->lines[bot]->hash != curscr->lines[bot]->hash
|| memcmp(win->lines[bot]->line,
curscr->lines[bot]->line,
win->maxx * __LDATASIZE) != 0)
break;
else
win->lines[bot]->flags &= ~__ISDIRTY;
#ifdef NO_JERKINESS
/*
* If we have a bottom unchanged region return. Scrolling the
* bottom region up and then back down causes a screen jitter.
* This will increase the number of characters sent to the screen
* but it looks better.
*/
if (bot < win->maxy - 1)
return;
#endif /* NO_JERKINESS */
/*
* Search for the largest block of text not changed.
* Invariants of the loop:
* - Startw is the index of the beginning of the examined block in win.
* - Starts is the index of the beginning of the examined block in
* curscr.
* - Curs is the index of one past the end of the exmined block in win.
* - Curw is the index of one past the end of the exmined block in
* curscr.
* - bsize is the current size of the examined block.
*/
for (bsize = bot - top; bsize >= THRESH; bsize--) {
for (startw = top; startw <= bot - bsize; startw++)
for (starts = top; starts <= bot - bsize;
starts++) {
for (curw = startw, curs = starts;
curs < starts + bsize; curw++, curs++)
if (win->lines[curw]->flags &
__FORCEPAINT ||
(win->lines[curw]->hash !=
curscr->lines[curs]->hash ||
memcmp(win->lines[curw]->line,
curscr->lines[curs]->line,
win->maxx * __LDATASIZE) != 0))
break;
if (curs == starts + bsize)
goto done;
}
}
done:
/* Did not find anything */
if (bsize < THRESH)
return;
#ifdef DEBUG
__CTRACE("quickch:bsize=%d,starts=%d,startw=%d,curw=%d,curs=%d,top=%d,bot=%d\n",
bsize, starts, startw, curw, curs, top, bot);
#endif
/*
* Make sure that there is no overlap between the bottom and top
* regions and the middle scrolled block.
*/
if (bot < curs)
bot = curs - 1;
if (top > starts)
top = starts;
n = startw - starts;
#ifdef DEBUG
__CTRACE("#####################################\n");
for (i = 0; i < curscr->maxy; i++) {
__CTRACE("C: %d:", i);
__CTRACE(" 0x%x \n", curscr->lines[i]->hash);
for (j = 0; j < curscr->maxx; j++)
__CTRACE("%c",
curscr->lines[i]->line[j].ch);
__CTRACE("\n");
for (j = 0; j < curscr->maxx; j++)
__CTRACE("%x",
curscr->lines[i]->line[j].attr);
__CTRACE("\n");
__CTRACE("W: %d:", i);
__CTRACE(" 0x%x \n", win->lines[i]->hash);
__CTRACE(" 0x%x ", win->lines[i]->flags);
for (j = 0; j < win->maxx; j++)
__CTRACE("%c",
win->lines[i]->line[j].ch);
__CTRACE("\n");
for (j = 0; j < win->maxx; j++)
__CTRACE("%x",
win->lines[i]->line[j].attr);
__CTRACE("\n");
}
#endif
/* So we don't have to call __hash() each time */
for (i = 0; i < win->maxx; i++) {
buf[i].ch = ' ';
buf[i].attr = 0;
}
blank_hash = __hash((char *) buf, win->maxx * __LDATASIZE);
/*
* Perform the rotation to maintain the consistency of curscr.
* This is hairy since we are doing an *in place* rotation.
* Invariants of the loop:
* - I is the index of the current line.
* - Target is the index of the target of line i.
* - Tmp1 points to current line (i).
* - Tmp2 and points to target line (target);
* - Cur_period is the index of the end of the current period.
* (see below).
*
* There are 2 major issues here that make this rotation non-trivial:
* 1. Scrolling in a scrolling region bounded by the top
* and bottom regions determined (whose size is sc_region).
* 2. As a result of the use of the mod function, there may be a
* period introduced, i.e., 2 maps to 4, 4 to 6, n-2 to 0, and
* 0 to 2, which then causes all odd lines not to be rotated.
* To remedy this, an index of the end ( = beginning) of the
* current 'period' is kept, cur_period, and when it is reached,
* the next period is started from cur_period + 1 which is
* guaranteed not to have been reached since that would mean that
* all records would have been reached. (think about it...).
*
* Lines in the rotation can have 3 attributes which are marked on the
* line so that curscr is consistent with the visual screen.
* 1. Not dirty -- lines inside the scrolled block, top region or
* bottom region.
* 2. Blank lines -- lines in the differential of the scrolling
* region adjacent to top and bot regions
* depending on scrolling direction.
* 3. Dirty line -- all other lines are marked dirty.
*/
sc_region = bot - top + 1;
i = top;
tmp1 = curscr->lines[top];
cur_period = top;
for (j = top; j <= bot; j++) {
target = (i - top + n + sc_region) % sc_region + top;
tmp2 = curscr->lines[target];
curscr->lines[target] = tmp1;
/* Mark block as clean and blank out scrolled lines. */
clp = curscr->lines[target];
#ifdef DEBUG
__CTRACE("quickch: n=%d startw=%d curw=%d i = %d target=%d ",
n, startw, curw, i, target);
#endif
if ((target >= startw && target < curw) || target < top
|| target > bot) {
#ifdef DEBUG
__CTRACE("-- notdirty");
#endif
win->lines[target]->flags &= ~__ISDIRTY;
} else if ((n > 0 && target >= top && target < top + n) ||
(n < 0 && target <= bot && target > bot + n)) {
if (clp->hash != blank_hash || memcmp(clp->line,
buf, win->maxx * __LDATASIZE) !=0) {
(void)memcpy(clp->line, buf,
win->maxx * __LDATASIZE);
#ifdef DEBUG
__CTRACE("-- blanked out: dirty");
#endif
clp->hash = blank_hash;
__touchline(win, target, 0, win->maxx - 1, 0);
} else {
__touchline(win, target, 0, win->maxx - 1, 0);
#ifdef DEBUG
__CTRACE(" -- blank line already: dirty");
#endif
}
} else {
#ifdef DEBUG
__CTRACE(" -- dirty");
#endif
__touchline(win, target, 0, win->maxx - 1, 0);
}
#ifdef DEBUG
__CTRACE("\n");
#endif
if (target == cur_period) {
i = target + 1;
tmp1 = curscr->lines[i];
cur_period = i;
} else {
tmp1 = tmp2;
i = target;
}
}
#ifdef DEBUG
__CTRACE("$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$\n");
for (i = 0; i < curscr->maxy; i++) {
__CTRACE("C: %d:", i);
for (j = 0; j < curscr->maxx; j++)
__CTRACE("%c",
curscr->lines[i]->line[j].ch);
__CTRACE("\n");
__CTRACE("W: %d:", i);
for (j = 0; j < win->maxx; j++)
__CTRACE("%c", win->lines[i]->line[j].ch);
__CTRACE("\n");
}
#endif
if (n != 0) {
WINDOW *wp;
scrolln(win, starts, startw, curs, bot, top);
/*
* Need to repoint any subwindow lines to the rotated
* line structured.
*/
for (wp = win->nextp; wp != win; wp = wp->nextp)
__set_subwin(win, wp);
}
}
/*
* scrolln --
* Scroll n lines, where n is starts - startw.
*/
static void
scrolln(win, starts, startw, curs, bot, top)
WINDOW *win;
int starts, startw, curs, bot, top;
{
int i, oy, ox, n;
oy = curscr->cury;
ox = curscr->curx;
n = starts - startw;
/*
* XXX
* The initial tests that set __noqch don't let us reach here unless
* we have either CS + HO + SF/sf/SR/sr, or AL + DL. SF/sf and SR/sr
* scrolling can only shift the entire scrolling region, not just a
* part of it, which means that the quickch() routine is going to be
* sadly disappointed in us if we don't have CS as well.
*
* If CS, HO and SF/sf are set, can use the scrolling region. Because
* the cursor position after CS is undefined, we need HO which gives us
* the ability to move to somewhere without knowledge of the current
* location of the cursor. Still call __mvcur() anyway, to update its
* idea of where the cursor is.
*
* When the scrolling region has been set, the cursor has to be at the
* last line of the region to make the scroll happen.
*
* Doing SF/SR or AL/DL appears faster on the screen than either sf/sr
* or al/dl, and, some terminals have AL/DL, sf/sr, and CS, but not
* SF/SR. So, if we're scrolling almost all of the screen, try and use
* AL/DL, otherwise use the scrolling region. The "almost all" is a
* shameless hack for vi.
*/
if (n > 0) {
if (CS != NULL && HO != NULL && (SF != NULL ||
((AL == NULL || DL == NULL ||
top > 3 || bot + 3 < win->maxy) && sf != NULL))) {
tputs(__tscroll(CS, top, bot + 1), 0, __cputchar);
__mvcur(oy, ox, 0, 0, 1);
tputs(HO, 0, __cputchar);
__mvcur(0, 0, bot, 0, 1);
if (SF != NULL)
tputs(__tscroll(SF, n, 0), 0, __cputchar);
else
for (i = 0; i < n; i++)
tputs(sf, 0, __cputchar);
tputs(__tscroll(CS, 0, win->maxy), 0, __cputchar);
__mvcur(bot, 0, 0, 0, 1);
tputs(HO, 0, __cputchar);
__mvcur(0, 0, oy, ox, 1);
return;
}
/* Scroll up the block. */
if (SF != NULL && top == 0) {
__mvcur(oy, ox, bot, 0, 1);
tputs(__tscroll(SF, n, 0), 0, __cputchar);
} else if (DL != NULL) {
__mvcur(oy, ox, top, 0, 1);
tputs(__tscroll(DL, n, 0), 0, __cputchar);
} else if (dl != NULL) {
__mvcur(oy, ox, top, 0, 1);
for (i = 0; i < n; i++)
tputs(dl, 0, __cputchar);
} else if (sf != NULL && top == 0) {
__mvcur(oy, ox, bot, 0, 1);
for (i = 0; i < n; i++)
tputs(sf, 0, __cputchar);
} else
abort();
/* Push down the bottom region. */
__mvcur(top, 0, bot - n + 1, 0, 1);
if (AL != NULL)
tputs(__tscroll(AL, n, 0), 0, __cputchar);
else if (al != NULL)
for (i = 0; i < n; i++)
tputs(al, 0, __cputchar);
else
abort();
__mvcur(bot - n + 1, 0, oy, ox, 1);
} else {
/*
* !!!
* n < 0
*
* If CS, HO and SR/sr are set, can use the scrolling region.
* See the above comments for details.
*/
if (CS != NULL && HO != NULL && (SR != NULL ||
((AL == NULL || DL == NULL ||
top > 3 || bot + 3 < win->maxy) && sr != NULL))) {
tputs(__tscroll(CS, top, bot + 1), 0, __cputchar);
__mvcur(oy, ox, 0, 0, 1);
tputs(HO, 0, __cputchar);
__mvcur(0, 0, top, 0, 1);
if (SR != NULL)
tputs(__tscroll(SR, -n, 0), 0, __cputchar);
else
for (i = n; i < 0; i++)
tputs(sr, 0, __cputchar);
tputs(__tscroll(CS, 0, win->maxy), 0, __cputchar);
__mvcur(top, 0, 0, 0, 1);
tputs(HO, 0, __cputchar);
__mvcur(0, 0, oy, ox, 1);
return;
}
/* Preserve the bottom lines. */
__mvcur(oy, ox, bot + n + 1, 0, 1);
if (SR != NULL && bot == win->maxy)
tputs(__tscroll(SR, -n, 0), 0, __cputchar);
else if (DL != NULL)
tputs(__tscroll(DL, -n, 0), 0, __cputchar);
else if (dl != NULL)
for (i = n; i < 0; i++)
tputs(dl, 0, __cputchar);
else if (sr != NULL && bot == win->maxy)
for (i = n; i < 0; i++)
tputs(sr, 0, __cputchar);
else
abort();
/* Scroll the block down. */
__mvcur(bot + n + 1, 0, top, 0, 1);
if (AL != NULL)
tputs(__tscroll(AL, -n, 0), 0, __cputchar);
else if (al != NULL)
for (i = n; i < 0; i++)
tputs(al, 0, __cputchar);
else
abort();
__mvcur(top, 0, oy, ox, 1);
}
}