freebsd-dev/contrib/nvi/vi/vs_smap.c
2015-04-10 17:50:28 +00:00

1243 lines
28 KiB
C

/*-
* Copyright (c) 1993, 1994
* The Regents of the University of California. All rights reserved.
* Copyright (c) 1993, 1994, 1995, 1996
* Keith Bostic. All rights reserved.
*
* See the LICENSE file for redistribution information.
*/
#include "config.h"
#ifndef lint
static const char sccsid[] = "$Id: vs_smap.c,v 10.31 2011/02/26 13:56:21 skimo Exp $";
#endif /* not lint */
#include <sys/types.h>
#include <sys/queue.h>
#include <sys/time.h>
#include <bitstring.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "../common/common.h"
#include "vi.h"
static int vs_deleteln(SCR *, int);
static int vs_insertln(SCR *, int);
static int vs_sm_delete(SCR *, recno_t);
static int vs_sm_down(SCR *, MARK *, recno_t, scroll_t, SMAP *);
static int vs_sm_erase(SCR *);
static int vs_sm_insert(SCR *, recno_t);
static int vs_sm_reset(SCR *, recno_t);
static int vs_sm_up(SCR *, MARK *, recno_t, scroll_t, SMAP *);
/*
* vs_change --
* Make a change to the screen.
*
* PUBLIC: int vs_change(SCR *, recno_t, lnop_t);
*/
int
vs_change(SCR *sp, recno_t lno, lnop_t op)
{
VI_PRIVATE *vip;
SMAP *p;
size_t cnt, oldy, oldx;
vip = VIP(sp);
/*
* XXX
* Very nasty special case. The historic vi code displays a single
* space (or a '$' if the list option is set) for the first line in
* an "empty" file. If we "insert" a line, that line gets scrolled
* down, not repainted, so it's incorrect when we refresh the screen.
* The vi text input functions detect it explicitly and don't insert
* a new line.
*
* Check for line #2 before going to the end of the file.
*/
if (((op == LINE_APPEND && lno == 0) ||
(op == LINE_INSERT && lno == 1)) &&
!db_exist(sp, 2)) {
lno = 1;
op = LINE_RESET;
}
/* Appending is the same as inserting, if the line is incremented. */
if (op == LINE_APPEND) {
++lno;
op = LINE_INSERT;
}
/* Ignore the change if the line is after the map. */
if (lno > TMAP->lno)
return (0);
/*
* If the line is before the map, and it's a decrement, decrement
* the map. If it's an increment, increment the map. Otherwise,
* ignore it.
*/
if (lno < HMAP->lno) {
switch (op) {
case LINE_APPEND:
abort();
/* NOTREACHED */
case LINE_DELETE:
for (p = HMAP, cnt = sp->t_rows; cnt--; ++p)
--p->lno;
if (sp->lno >= lno)
--sp->lno;
F_SET(vip, VIP_N_RENUMBER);
break;
case LINE_INSERT:
for (p = HMAP, cnt = sp->t_rows; cnt--; ++p)
++p->lno;
if (sp->lno >= lno)
++sp->lno;
F_SET(vip, VIP_N_RENUMBER);
break;
case LINE_RESET:
break;
}
return (0);
}
F_SET(vip, VIP_N_REFRESH);
/*
* Invalidate the line size cache, and invalidate the cursor if it's
* on this line,
*/
VI_SCR_CFLUSH(vip);
if (sp->lno == lno)
F_SET(vip, VIP_CUR_INVALID);
/*
* If ex modifies the screen after ex output is already on the screen
* or if we've switched into ex canonical mode, don't touch it -- we'll
* get scrolling wrong, at best.
*/
if (!F_ISSET(sp, SC_TINPUT_INFO) &&
(F_ISSET(sp, SC_SCR_EXWROTE) || VIP(sp)->totalcount > 1)) {
F_SET(vip, VIP_N_EX_REDRAW);
return (0);
}
/* Save and restore the cursor for these routines. */
(void)sp->gp->scr_cursor(sp, &oldy, &oldx);
switch (op) {
case LINE_DELETE:
if (vs_sm_delete(sp, lno))
return (1);
if (sp->lno > lno)
--sp->lno;
F_SET(vip, VIP_N_RENUMBER);
break;
case LINE_INSERT:
if (vs_sm_insert(sp, lno))
return (1);
if (sp->lno > lno)
++sp->lno;
F_SET(vip, VIP_N_RENUMBER);
break;
case LINE_RESET:
if (vs_sm_reset(sp, lno))
return (1);
break;
default:
abort();
}
(void)sp->gp->scr_move(sp, oldy, oldx);
return (0);
}
/*
* vs_sm_fill --
* Fill in the screen map, placing the specified line at the
* right position. There isn't any way to tell if an SMAP
* entry has been filled in, so this routine had better be
* called with P_FILL set before anything else is done.
*
* !!!
* Unexported interface: if lno is OOBLNO, P_TOP means that the HMAP
* slot is already filled in, P_BOTTOM means that the TMAP slot is
* already filled in, and we just finish up the job.
*
* PUBLIC: int vs_sm_fill(SCR *, recno_t, pos_t);
*/
int
vs_sm_fill(SCR *sp, recno_t lno, pos_t pos)
{
SMAP *p, tmp;
size_t cnt;
/* Flush all cached information from the SMAP. */
for (p = HMAP, cnt = sp->t_rows; cnt--; ++p)
SMAP_FLUSH(p);
/*
* If the map is filled, the screen must be redrawn.
*
* XXX
* This is a bug. We should try and figure out if the desired line
* is already in the map or close by -- scrolling the screen would
* be a lot better than redrawing.
*/
F_SET(sp, SC_SCR_REDRAW);
switch (pos) {
case P_FILL:
tmp.lno = 1;
tmp.coff = 0;
tmp.soff = 1;
/* See if less than half a screen from the top. */
if (vs_sm_nlines(sp,
&tmp, lno, HALFTEXT(sp)) <= HALFTEXT(sp)) {
lno = 1;
goto top;
}
/* See if less than half a screen from the bottom. */
if (db_last(sp, &tmp.lno))
return (1);
tmp.coff = 0;
tmp.soff = vs_screens(sp, tmp.lno, NULL);
if (vs_sm_nlines(sp,
&tmp, lno, HALFTEXT(sp)) <= HALFTEXT(sp)) {
TMAP->lno = tmp.lno;
TMAP->coff = tmp.coff;
TMAP->soff = tmp.soff;
goto bottom;
}
goto middle;
case P_TOP:
if (lno != OOBLNO) {
top: HMAP->lno = lno;
HMAP->coff = 0;
HMAP->soff = 1;
} else {
/*
* If number of lines HMAP->lno (top line) spans
* changed due to, say reformatting, and now is
* fewer than HMAP->soff, reset so the line is
* redrawn at the top of the screen.
*/
cnt = vs_screens(sp, HMAP->lno, NULL);
if (cnt < HMAP->soff)
HMAP->soff = 1;
}
/* If we fail, just punt. */
for (p = HMAP, cnt = sp->t_rows; --cnt; ++p)
if (vs_sm_next(sp, p, p + 1))
goto err;
break;
case P_MIDDLE:
/* If we fail, guess that the file is too small. */
middle: p = HMAP + sp->t_rows / 2;
p->lno = lno;
p->coff = 0;
p->soff = 1;
for (; p > HMAP; --p)
if (vs_sm_prev(sp, p, p - 1)) {
lno = 1;
goto top;
}
/* If we fail, just punt. */
p = HMAP + sp->t_rows / 2;
for (; p < TMAP; ++p)
if (vs_sm_next(sp, p, p + 1))
goto err;
break;
case P_BOTTOM:
if (lno != OOBLNO) {
TMAP->lno = lno;
TMAP->coff = 0;
TMAP->soff = vs_screens(sp, lno, NULL);
}
/* If we fail, guess that the file is too small. */
bottom: for (p = TMAP; p > HMAP; --p)
if (vs_sm_prev(sp, p, p - 1)) {
lno = 1;
goto top;
}
break;
default:
abort();
}
return (0);
/*
* Try and put *something* on the screen. If this fails, we have a
* serious hard error.
*/
err: HMAP->lno = 1;
HMAP->coff = 0;
HMAP->soff = 1;
for (p = HMAP; p < TMAP; ++p)
if (vs_sm_next(sp, p, p + 1))
return (1);
return (0);
}
/*
* For the routines vs_sm_reset, vs_sm_delete and vs_sm_insert: if the
* screen contains only a single line (whether because the screen is small
* or the line large), it gets fairly exciting. Skip the fun, set a flag
* so the screen map is refilled and the screen redrawn, and return. This
* is amazingly slow, but it's not clear that anyone will care.
*/
#define HANDLE_WEIRDNESS(cnt) { \
if (cnt >= sp->t_rows) { \
F_SET(sp, SC_SCR_REFORMAT); \
return (0); \
} \
}
/*
* vs_sm_delete --
* Delete a line out of the SMAP.
*/
static int
vs_sm_delete(SCR *sp, recno_t lno)
{
SMAP *p, *t;
size_t cnt_orig;
/*
* Find the line in the map, and count the number of screen lines
* which display any part of the deleted line.
*/
for (p = HMAP; p->lno != lno; ++p);
if (O_ISSET(sp, O_LEFTRIGHT))
cnt_orig = 1;
else
for (cnt_orig = 1, t = p + 1;
t <= TMAP && t->lno == lno; ++cnt_orig, ++t);
HANDLE_WEIRDNESS(cnt_orig);
/* Delete that many lines from the screen. */
(void)sp->gp->scr_move(sp, p - HMAP, 0);
if (vs_deleteln(sp, cnt_orig))
return (1);
/* Shift the screen map up. */
memmove(p, p + cnt_orig, (((TMAP - p) - cnt_orig) + 1) * sizeof(SMAP));
/* Decrement the line numbers for the rest of the map. */
for (t = TMAP - cnt_orig; p <= t; ++p)
--p->lno;
/* Display the new lines. */
for (p = TMAP - cnt_orig;;) {
if (p < TMAP && vs_sm_next(sp, p, p + 1))
return (1);
/* vs_sm_next() flushed the cache. */
if (vs_line(sp, ++p, NULL, NULL))
return (1);
if (p == TMAP)
break;
}
return (0);
}
/*
* vs_sm_insert --
* Insert a line into the SMAP.
*/
static int
vs_sm_insert(SCR *sp, recno_t lno)
{
SMAP *p, *t;
size_t cnt_orig, cnt, coff;
/* Save the offset. */
coff = HMAP->coff;
/*
* Find the line in the map, find out how many screen lines
* needed to display the line.
*/
for (p = HMAP; p->lno != lno; ++p);
cnt_orig = vs_screens(sp, lno, NULL);
HANDLE_WEIRDNESS(cnt_orig);
/*
* The lines left in the screen override the number of screen
* lines in the inserted line.
*/
cnt = (TMAP - p) + 1;
if (cnt_orig > cnt)
cnt_orig = cnt;
/* Push down that many lines. */
(void)sp->gp->scr_move(sp, p - HMAP, 0);
if (vs_insertln(sp, cnt_orig))
return (1);
/* Shift the screen map down. */
memmove(p + cnt_orig, p, (((TMAP - p) - cnt_orig) + 1) * sizeof(SMAP));
/* Increment the line numbers for the rest of the map. */
for (t = p + cnt_orig; t <= TMAP; ++t)
++t->lno;
/* Fill in the SMAP for the new lines, and display. */
for (cnt = 1, t = p; cnt <= cnt_orig; ++t, ++cnt) {
t->lno = lno;
t->coff = coff;
t->soff = cnt;
SMAP_FLUSH(t);
if (vs_line(sp, t, NULL, NULL))
return (1);
}
return (0);
}
/*
* vs_sm_reset --
* Reset a line in the SMAP.
*/
static int
vs_sm_reset(SCR *sp, recno_t lno)
{
SMAP *p, *t;
size_t cnt_orig, cnt_new, cnt, diff;
/*
* See if the number of on-screen rows taken up by the old display
* for the line is the same as the number needed for the new one.
* If so, repaint, otherwise do it the hard way.
*/
for (p = HMAP; p->lno != lno; ++p);
if (O_ISSET(sp, O_LEFTRIGHT)) {
t = p;
cnt_orig = cnt_new = 1;
} else {
for (cnt_orig = 0,
t = p; t <= TMAP && t->lno == lno; ++cnt_orig, ++t);
cnt_new = vs_screens(sp, lno, NULL);
}
HANDLE_WEIRDNESS(cnt_orig);
if (cnt_orig == cnt_new) {
do {
SMAP_FLUSH(p);
if (vs_line(sp, p, NULL, NULL))
return (1);
} while (++p < t);
return (0);
}
if (cnt_orig < cnt_new) {
/* Get the difference. */
diff = cnt_new - cnt_orig;
/*
* The lines left in the screen override the number of screen
* lines in the inserted line.
*/
cnt = (TMAP - p) + 1;
if (diff > cnt)
diff = cnt;
/* If there are any following lines, push them down. */
if (cnt > 1) {
(void)sp->gp->scr_move(sp, p - HMAP, 0);
if (vs_insertln(sp, diff))
return (1);
/* Shift the screen map down. */
memmove(p + diff, p,
(((TMAP - p) - diff) + 1) * sizeof(SMAP));
}
/* Fill in the SMAP for the replaced line, and display. */
for (cnt = 1, t = p; cnt_new-- && t <= TMAP; ++t, ++cnt) {
t->lno = lno;
t->soff = cnt;
SMAP_FLUSH(t);
if (vs_line(sp, t, NULL, NULL))
return (1);
}
} else {
/* Get the difference. */
diff = cnt_orig - cnt_new;
/* Delete that many lines from the screen. */
(void)sp->gp->scr_move(sp, p - HMAP, 0);
if (vs_deleteln(sp, diff))
return (1);
/* Shift the screen map up. */
memmove(p, p + diff, (((TMAP - p) - diff) + 1) * sizeof(SMAP));
/* Fill in the SMAP for the replaced line, and display. */
for (cnt = 1, t = p; cnt_new--; ++t, ++cnt) {
t->lno = lno;
t->soff = cnt;
SMAP_FLUSH(t);
if (vs_line(sp, t, NULL, NULL))
return (1);
}
/* Display the new lines at the bottom of the screen. */
for (t = TMAP - diff;;) {
if (t < TMAP && vs_sm_next(sp, t, t + 1))
return (1);
/* vs_sm_next() flushed the cache. */
if (vs_line(sp, ++t, NULL, NULL))
return (1);
if (t == TMAP)
break;
}
}
return (0);
}
/*
* vs_sm_scroll
* Scroll the SMAP up/down count logical lines. Different
* semantics based on the vi command, *sigh*.
*
* PUBLIC: int vs_sm_scroll(SCR *, MARK *, recno_t, scroll_t);
*/
int
vs_sm_scroll(SCR *sp, MARK *rp, recno_t count, scroll_t scmd)
{
SMAP *smp;
/*
* Invalidate the cursor. The line is probably going to change,
* (although for ^E and ^Y it may not). In any case, the scroll
* routines move the cursor to draw things.
*/
F_SET(VIP(sp), VIP_CUR_INVALID);
/* Find the cursor in the screen. */
if (vs_sm_cursor(sp, &smp))
return (1);
switch (scmd) {
case CNTRL_B:
case CNTRL_U:
case CNTRL_Y:
case Z_CARAT:
if (vs_sm_down(sp, rp, count, scmd, smp))
return (1);
break;
case CNTRL_D:
case CNTRL_E:
case CNTRL_F:
case Z_PLUS:
if (vs_sm_up(sp, rp, count, scmd, smp))
return (1);
break;
default:
abort();
}
/*
* !!!
* If we're at the start of a line, go for the first non-blank.
* This makes it look like the old vi, even though we're moving
* around by logical lines, not physical ones.
*
* XXX
* In the presence of a long line, which has more than a screen
* width of leading spaces, this code can cause a cursor warp.
* Live with it.
*/
if (scmd != CNTRL_E && scmd != CNTRL_Y &&
rp->cno == 0 && nonblank(sp, rp->lno, &rp->cno))
return (1);
return (0);
}
/*
* vs_sm_up --
* Scroll the SMAP up count logical lines.
*/
static int
vs_sm_up(SCR *sp, MARK *rp, recno_t count, scroll_t scmd, SMAP *smp)
{
int cursor_set, echanged, zset;
SMAP *ssmp, s1, s2;
/*
* Check to see if movement is possible.
*
* Get the line after the map. If that line is a new one (and if
* O_LEFTRIGHT option is set, this has to be true), and the next
* line doesn't exist, and the cursor doesn't move, or the cursor
* isn't even on the screen, or the cursor is already at the last
* line in the map, it's an error. If that test succeeded because
* the cursor wasn't at the end of the map, test to see if the map
* is mostly empty.
*/
if (vs_sm_next(sp, TMAP, &s1))
return (1);
if (s1.lno > TMAP->lno && !db_exist(sp, s1.lno)) {
if (scmd == CNTRL_E || scmd == Z_PLUS || smp == TMAP) {
v_eof(sp, NULL);
return (1);
}
if (vs_sm_next(sp, smp, &s1))
return (1);
if (s1.lno > smp->lno && !db_exist(sp, s1.lno)) {
v_eof(sp, NULL);
return (1);
}
}
/*
* Small screens: see vs_refresh.c section 6a.
*
* If it's a small screen, and the movement isn't larger than a
* screen, i.e some context will remain, open up the screen and
* display by scrolling. In this case, the cursor moves down one
* line for each line displayed. Otherwise, erase/compress and
* repaint, and move the cursor to the first line in the screen.
* Note, the ^F command is always in the latter case, for historical
* reasons.
*/
cursor_set = 0;
if (IS_SMALL(sp)) {
if (count >= sp->t_maxrows || scmd == CNTRL_F) {
s1 = TMAP[0];
if (vs_sm_erase(sp))
return (1);
for (; count--; s1 = s2) {
if (vs_sm_next(sp, &s1, &s2))
return (1);
if (s2.lno != s1.lno && !db_exist(sp, s2.lno))
break;
}
TMAP[0] = s2;
if (vs_sm_fill(sp, OOBLNO, P_BOTTOM))
return (1);
return (vs_sm_position(sp, rp, 0, P_TOP));
}
cursor_set = scmd == CNTRL_E || vs_sm_cursor(sp, &ssmp);
for (; count &&
sp->t_rows != sp->t_maxrows; --count, ++sp->t_rows) {
if (vs_sm_next(sp, TMAP, &s1))
return (1);
if (TMAP->lno != s1.lno && !db_exist(sp, s1.lno))
break;
*++TMAP = s1;
/* vs_sm_next() flushed the cache. */
if (vs_line(sp, TMAP, NULL, NULL))
return (1);
if (!cursor_set)
++ssmp;
}
if (!cursor_set) {
rp->lno = ssmp->lno;
rp->cno = ssmp->c_sboff;
}
if (count == 0)
return (0);
}
for (echanged = zset = 0; count; --count) {
/* Decide what would show up on the screen. */
if (vs_sm_next(sp, TMAP, &s1))
return (1);
/* If the line doesn't exist, we're done. */
if (TMAP->lno != s1.lno && !db_exist(sp, s1.lno))
break;
/* Scroll the screen cursor up one logical line. */
if (vs_sm_1up(sp))
return (1);
switch (scmd) {
case CNTRL_E:
if (smp > HMAP)
--smp;
else
echanged = 1;
break;
case Z_PLUS:
if (zset) {
if (smp > HMAP)
--smp;
} else {
smp = TMAP;
zset = 1;
}
/* FALLTHROUGH */
default:
break;
}
}
if (cursor_set)
return(0);
switch (scmd) {
case CNTRL_E:
/*
* On a ^E that was forced to change lines, try and keep the
* cursor as close as possible to the last position, but also
* set it up so that the next "real" movement will return the
* cursor to the closest position to the last real movement.
*/
if (echanged) {
rp->lno = smp->lno;
rp->cno = vs_colpos(sp, smp->lno,
(O_ISSET(sp, O_LEFTRIGHT) ?
smp->coff : (smp->soff - 1) * sp->cols) +
sp->rcm % sp->cols);
}
return (0);
case CNTRL_F:
/*
* If there are more lines, the ^F command is positioned at
* the first line of the screen.
*/
if (!count) {
smp = HMAP;
break;
}
/* FALLTHROUGH */
case CNTRL_D:
/*
* The ^D and ^F commands move the cursor towards EOF
* if there are more lines to move. Check to be sure
* the lines actually exist. (They may not if the
* file is smaller than the screen.)
*/
for (; count; --count, ++smp)
if (smp == TMAP || !db_exist(sp, smp[1].lno))
break;
break;
case Z_PLUS:
/* The z+ command moves the cursor to the first new line. */
break;
default:
abort();
}
if (!SMAP_CACHE(smp) && vs_line(sp, smp, NULL, NULL))
return (1);
rp->lno = smp->lno;
rp->cno = smp->c_scoff == 255 ? 0 : smp->c_sboff;
return (0);
}
/*
* vs_sm_1up --
* Scroll the SMAP up one.
*
* PUBLIC: int vs_sm_1up(SCR *);
*/
int
vs_sm_1up(SCR *sp)
{
/*
* Delete the top line of the screen. Shift the screen map
* up and display a new line at the bottom of the screen.
*/
(void)sp->gp->scr_move(sp, 0, 0);
if (vs_deleteln(sp, 1))
return (1);
/* One-line screens can fail. */
if (IS_ONELINE(sp)) {
if (vs_sm_next(sp, TMAP, TMAP))
return (1);
} else {
memmove(HMAP, HMAP + 1, (sp->rows - 1) * sizeof(SMAP));
if (vs_sm_next(sp, TMAP - 1, TMAP))
return (1);
}
/* vs_sm_next() flushed the cache. */
return (vs_line(sp, TMAP, NULL, NULL));
}
/*
* vs_deleteln --
* Delete a line a la curses, make sure to put the information
* line and other screens back.
*/
static int
vs_deleteln(SCR *sp, int cnt)
{
GS *gp;
size_t oldy, oldx;
gp = sp->gp;
/* If the screen is vertically split, we can't scroll it. */
if (IS_VSPLIT(sp)) {
F_SET(sp, SC_SCR_REDRAW);
return (0);
}
if (IS_ONELINE(sp))
(void)gp->scr_clrtoeol(sp);
else {
(void)gp->scr_cursor(sp, &oldy, &oldx);
while (cnt--) {
(void)gp->scr_deleteln(sp);
(void)gp->scr_move(sp, LASTLINE(sp), 0);
(void)gp->scr_insertln(sp);
(void)gp->scr_move(sp, oldy, oldx);
}
}
return (0);
}
/*
* vs_sm_down --
* Scroll the SMAP down count logical lines.
*/
static int
vs_sm_down(SCR *sp, MARK *rp, recno_t count, scroll_t scmd, SMAP *smp)
{
SMAP *ssmp, s1, s2;
int cursor_set, ychanged, zset;
/* Check to see if movement is possible. */
if (HMAP->lno == 1 &&
(O_ISSET(sp, O_LEFTRIGHT) || HMAP->soff == 1) &&
(scmd == CNTRL_Y || scmd == Z_CARAT || smp == HMAP)) {
v_sof(sp, NULL);
return (1);
}
/*
* Small screens: see vs_refresh.c section 6a.
*
* If it's a small screen, and the movement isn't larger than a
* screen, i.e some context will remain, open up the screen and
* display by scrolling. In this case, the cursor moves up one
* line for each line displayed. Otherwise, erase/compress and
* repaint, and move the cursor to the first line in the screen.
* Note, the ^B command is always in the latter case, for historical
* reasons.
*/
cursor_set = scmd == CNTRL_Y;
if (IS_SMALL(sp)) {
if (count >= sp->t_maxrows || scmd == CNTRL_B) {
s1 = HMAP[0];
if (vs_sm_erase(sp))
return (1);
for (; count--; s1 = s2) {
if (vs_sm_prev(sp, &s1, &s2))
return (1);
if (s2.lno == 1 &&
(O_ISSET(sp, O_LEFTRIGHT) || s2.soff == 1))
break;
}
HMAP[0] = s2;
if (vs_sm_fill(sp, OOBLNO, P_TOP))
return (1);
return (vs_sm_position(sp, rp, 0, P_BOTTOM));
}
cursor_set = scmd == CNTRL_Y || vs_sm_cursor(sp, &ssmp);
for (; count &&
sp->t_rows != sp->t_maxrows; --count, ++sp->t_rows) {
if (HMAP->lno == 1 &&
(O_ISSET(sp, O_LEFTRIGHT) || HMAP->soff == 1))
break;
++TMAP;
if (vs_sm_1down(sp))
return (1);
}
if (!cursor_set) {
rp->lno = ssmp->lno;
rp->cno = ssmp->c_sboff;
}
if (count == 0)
return (0);
}
for (ychanged = zset = 0; count; --count) {
/* If the line doesn't exist, we're done. */
if (HMAP->lno == 1 &&
(O_ISSET(sp, O_LEFTRIGHT) || HMAP->soff == 1))
break;
/* Scroll the screen and cursor down one logical line. */
if (vs_sm_1down(sp))
return (1);
switch (scmd) {
case CNTRL_Y:
if (smp < TMAP)
++smp;
else
ychanged = 1;
break;
case Z_CARAT:
if (zset) {
if (smp < TMAP)
++smp;
} else {
smp = HMAP;
zset = 1;
}
/* FALLTHROUGH */
default:
break;
}
}
if (scmd != CNTRL_Y && cursor_set)
return(0);
switch (scmd) {
case CNTRL_B:
/*
* If there are more lines, the ^B command is positioned at
* the last line of the screen. However, the line may not
* exist.
*/
if (!count) {
for (smp = TMAP; smp > HMAP; --smp)
if (db_exist(sp, smp->lno))
break;
break;
}
/* FALLTHROUGH */
case CNTRL_U:
/*
* The ^B and ^U commands move the cursor towards SOF
* if there are more lines to move.
*/
if (count < smp - HMAP)
smp -= count;
else
smp = HMAP;
break;
case CNTRL_Y:
/*
* On a ^Y that was forced to change lines, try and keep the
* cursor as close as possible to the last position, but also
* set it up so that the next "real" movement will return the
* cursor to the closest position to the last real movement.
*/
if (ychanged) {
rp->lno = smp->lno;
rp->cno = vs_colpos(sp, smp->lno,
(O_ISSET(sp, O_LEFTRIGHT) ?
smp->coff : (smp->soff - 1) * sp->cols) +
sp->rcm % sp->cols);
}
return (0);
case Z_CARAT:
/* The z^ command moves the cursor to the first new line. */
break;
default:
abort();
}
if (!SMAP_CACHE(smp) && vs_line(sp, smp, NULL, NULL))
return (1);
rp->lno = smp->lno;
rp->cno = smp->c_scoff == 255 ? 0 : smp->c_sboff;
return (0);
}
/*
* vs_sm_erase --
* Erase the small screen area for the scrolling functions.
*/
static int
vs_sm_erase(SCR *sp)
{
GS *gp;
gp = sp->gp;
(void)gp->scr_move(sp, LASTLINE(sp), 0);
(void)gp->scr_clrtoeol(sp);
for (; sp->t_rows > sp->t_minrows; --sp->t_rows, --TMAP) {
(void)gp->scr_move(sp, TMAP - HMAP, 0);
(void)gp->scr_clrtoeol(sp);
}
return (0);
}
/*
* vs_sm_1down --
* Scroll the SMAP down one.
*
* PUBLIC: int vs_sm_1down(SCR *);
*/
int
vs_sm_1down(SCR *sp)
{
/*
* Insert a line at the top of the screen. Shift the screen map
* down and display a new line at the top of the screen.
*/
(void)sp->gp->scr_move(sp, 0, 0);
if (vs_insertln(sp, 1))
return (1);
/* One-line screens can fail. */
if (IS_ONELINE(sp)) {
if (vs_sm_prev(sp, HMAP, HMAP))
return (1);
} else {
memmove(HMAP + 1, HMAP, (sp->rows - 1) * sizeof(SMAP));
if (vs_sm_prev(sp, HMAP + 1, HMAP))
return (1);
}
/* vs_sm_prev() flushed the cache. */
return (vs_line(sp, HMAP, NULL, NULL));
}
/*
* vs_insertln --
* Insert a line a la curses, make sure to put the information
* line and other screens back.
*/
static int
vs_insertln(SCR *sp, int cnt)
{
GS *gp;
size_t oldy, oldx;
gp = sp->gp;
/* If the screen is vertically split, we can't scroll it. */
if (IS_VSPLIT(sp)) {
F_SET(sp, SC_SCR_REDRAW);
return (0);
}
if (IS_ONELINE(sp)) {
(void)gp->scr_move(sp, LASTLINE(sp), 0);
(void)gp->scr_clrtoeol(sp);
} else {
(void)gp->scr_cursor(sp, &oldy, &oldx);
while (cnt--) {
(void)gp->scr_move(sp, LASTLINE(sp) - 1, 0);
(void)gp->scr_deleteln(sp);
(void)gp->scr_move(sp, oldy, oldx);
(void)gp->scr_insertln(sp);
}
}
return (0);
}
/*
* vs_sm_next --
* Fill in the next entry in the SMAP.
*
* PUBLIC: int vs_sm_next(SCR *, SMAP *, SMAP *);
*/
int
vs_sm_next(SCR *sp, SMAP *p, SMAP *t)
{
size_t lcnt;
SMAP_FLUSH(t);
if (O_ISSET(sp, O_LEFTRIGHT)) {
t->lno = p->lno + 1;
t->coff = p->coff;
} else {
lcnt = vs_screens(sp, p->lno, NULL);
if (lcnt == p->soff) {
t->lno = p->lno + 1;
t->soff = 1;
} else {
t->lno = p->lno;
t->soff = p->soff + 1;
}
}
return (0);
}
/*
* vs_sm_prev --
* Fill in the previous entry in the SMAP.
*
* PUBLIC: int vs_sm_prev(SCR *, SMAP *, SMAP *);
*/
int
vs_sm_prev(SCR *sp, SMAP *p, SMAP *t)
{
SMAP_FLUSH(t);
if (O_ISSET(sp, O_LEFTRIGHT)) {
t->lno = p->lno - 1;
t->coff = p->coff;
} else {
if (p->soff != 1) {
t->lno = p->lno;
t->soff = p->soff - 1;
} else {
t->lno = p->lno - 1;
t->soff = vs_screens(sp, t->lno, NULL);
}
}
return (t->lno == 0);
}
/*
* vs_sm_cursor --
* Return the SMAP entry referenced by the cursor.
*
* PUBLIC: int vs_sm_cursor(SCR *, SMAP **);
*/
int
vs_sm_cursor(SCR *sp, SMAP **smpp)
{
SMAP *p;
/* See if the cursor is not in the map. */
if (sp->lno < HMAP->lno || sp->lno > TMAP->lno)
return (1);
/* Find the first occurence of the line. */
for (p = HMAP; p->lno != sp->lno; ++p);
/* Fill in the map information until we find the right line. */
for (; p <= TMAP; ++p) {
/* Short lines are common and easy to detect. */
if (p != TMAP && (p + 1)->lno != p->lno) {
*smpp = p;
return (0);
}
if (!SMAP_CACHE(p) && vs_line(sp, p, NULL, NULL))
return (1);
if (p->c_eboff >= sp->cno) {
*smpp = p;
return (0);
}
}
/* It was past the end of the map after all. */
return (1);
}
/*
* vs_sm_position --
* Return the line/column of the top, middle or last line on the screen.
* (The vi H, M and L commands.) Here because only the screen routines
* know what's really out there.
*
* PUBLIC: int vs_sm_position(SCR *, MARK *, u_long, pos_t);
*/
int
vs_sm_position(SCR *sp, MARK *rp, u_long cnt, pos_t pos)
{
SMAP *smp;
recno_t last;
switch (pos) {
case P_TOP:
/*
* !!!
* Historically, an invalid count to the H command failed.
* We do nothing special here, just making sure that H in
* an empty screen works.
*/
if (cnt > TMAP - HMAP)
goto sof;
smp = HMAP + cnt;
if (cnt && !db_exist(sp, smp->lno)) {
sof: msgq(sp, M_BERR, "220|Movement past the end-of-screen");
return (1);
}
break;
case P_MIDDLE:
/*
* !!!
* Historically, a count to the M command was ignored.
* If the screen isn't filled, find the middle of what's
* real and move there.
*/
if (!db_exist(sp, TMAP->lno)) {
if (db_last(sp, &last))
return (1);
for (smp = TMAP; smp->lno > last && smp > HMAP; --smp);
if (smp > HMAP)
smp -= (smp - HMAP) / 2;
} else
smp = (HMAP + (TMAP - HMAP) / 2) + cnt;
break;
case P_BOTTOM:
/*
* !!!
* Historically, an invalid count to the L command failed.
* If the screen isn't filled, find the bottom of what's
* real and try to offset from there.
*/
if (cnt > TMAP - HMAP)
goto eof;
smp = TMAP - cnt;
if (!db_exist(sp, smp->lno)) {
if (db_last(sp, &last))
return (1);
for (; smp->lno > last && smp > HMAP; --smp);
if (cnt > smp - HMAP) {
eof: msgq(sp, M_BERR,
"221|Movement past the beginning-of-screen");
return (1);
}
smp -= cnt;
}
break;
default:
abort();
}
/* Make sure that the cached information is valid. */
if (!SMAP_CACHE(smp) && vs_line(sp, smp, NULL, NULL))
return (1);
rp->lno = smp->lno;
rp->cno = smp->c_sboff;
return (0);
}
/*
* vs_sm_nlines --
* Return the number of screen lines from an SMAP entry to the
* start of some file line, less than a maximum value.
*
* PUBLIC: recno_t vs_sm_nlines(SCR *, SMAP *, recno_t, size_t);
*/
recno_t
vs_sm_nlines(SCR *sp, SMAP *from_sp, recno_t to_lno, size_t max)
{
recno_t lno, lcnt;
if (O_ISSET(sp, O_LEFTRIGHT))
return (from_sp->lno > to_lno ?
from_sp->lno - to_lno : to_lno - from_sp->lno);
if (from_sp->lno == to_lno)
return (from_sp->soff - 1);
if (from_sp->lno > to_lno) {
lcnt = from_sp->soff - 1; /* Correct for off-by-one. */
for (lno = from_sp->lno; --lno >= to_lno && lcnt <= max;)
lcnt += vs_screens(sp, lno, NULL);
} else {
lno = from_sp->lno;
lcnt = (vs_screens(sp, lno, NULL) - from_sp->soff) + 1;
for (; ++lno < to_lno && lcnt <= max;)
lcnt += vs_screens(sp, lno, NULL);
}
return (lcnt);
}