4.4BSD/usr/src/contrib/nvi/nvi/vi/v_scroll.c
/*-
* Copyright (c) 1992, 1993
* 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.
*/
#ifndef lint
static char sccsid[] = "@(#)v_scroll.c 8.1 (Berkeley) 6/9/93";
#endif /* not lint */
#include <sys/types.h>
#include "vi.h"
#include "vcmd.h"
/*
* v_lgoto -- [count]G
* Go to first non-blank character of the line count, the last line
* of the file by default.
*/
int
v_lgoto(sp, ep, vp, fm, tm, rp)
SCR *sp;
EXF *ep;
VICMDARG *vp;
MARK *fm, *tm, *rp;
{
recno_t last;
if (file_lline(sp, ep, &last))
return (1);
if (F_ISSET(vp, VC_C1SET)) {
if (last < vp->count) {
v_eof(sp, ep, fm);
return (1);
}
rp->lno = vp->count;
} else
rp->lno = last ? last : 1;
return (0);
}
/*
* v_home -- [count]H
* Move to the first non-blank character of the line count from
* the top of the screen, 1 by default.
*/
int
v_home(sp, ep, vp, fm, tm, rp)
SCR *sp;
EXF *ep;
VICMDARG *vp;
MARK *fm, *tm, *rp;
{
return (sp->s_position(sp, ep, &rp->lno,
F_ISSET(vp, VC_C1SET) ? vp->count : 1, P_TOP));
}
/*
* v_middle -- M
* Move to the first non-blank character of the line in the middle
* of the screen.
*/
int
v_middle(sp, ep, vp, fm, tm, rp)
SCR *sp;
EXF *ep;
VICMDARG *vp;
MARK *fm, *tm, *rp;
{
return (sp->s_position(sp, ep, &rp->lno, 0, P_MIDDLE));
}
/*
* v_bottom -- [count]L
* Move to the first non-blank character of the line count from
* the bottom of the screen, 1 by default.
*/
int
v_bottom(sp, ep, vp, fm, tm, rp)
SCR *sp;
EXF *ep;
VICMDARG *vp;
MARK *fm, *tm, *rp;
{
return (sp->s_position(sp, ep, &rp->lno,
F_ISSET(vp, VC_C1SET) ? vp->count : 1, P_BOTTOM));
}
/*
* v_up -- [count]^P, [count]k, [count]-
* Move up by lines.
*/
int
v_up(sp, ep, vp, fm, tm, rp)
SCR *sp;
EXF *ep;
VICMDARG *vp;
MARK *fm, *tm, *rp;
{
recno_t lno;
lno = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
if (fm->lno <= lno) {
v_sof(sp, fm);
return (1);
}
rp->lno = fm->lno - lno;
return (0);
}
/*
* v_down -- [count]^J, [count]^N, [count]j, [count]^M, [count]+
* Move down by lines.
*/
int
v_down(sp, ep, vp, fm, tm, rp)
SCR *sp;
EXF *ep;
VICMDARG *vp;
MARK *fm, *tm, *rp;
{
recno_t lno;
size_t len;
lno = fm->lno + (F_ISSET(vp, VC_C1SET) ? vp->count : 1);
if (file_gline(sp, ep, lno, &len) == NULL) {
v_eof(sp, ep, fm);
return (1);
}
rp->lno = lno;
rp->cno = len ? fm->cno > len - 1 ? len - 1 : fm->cno : 0;
return (0);
}
/*
* The historic vi had a problem in that all movements were by physical
* lines, not by logical, or screen lines. Arguments can be made that this
* is the right thing to do. For example, single line movements, such as
* 'j' or 'k', should probably work on physical lines. Commands like "dj",
* or "j.", where '.' is a change command, make more sense for physical lines
* than they do logical lines. The arguments, however, don't apply to
* scrolling commands like ^D and ^F -- if the window is fairly small, using
* physical lines can result in a half-page scroll repainting the entire
* screen, which is not what the user wanted. In addition, if the line is
* large and the screen is small, using physical lines can make it impossible
* to display parts of the line. This implementation does the scrolling
* (^B, ^D, ^F, ^U), ^Y and ^E commands using logical lines, not physical.
*
* Another minor issue is that historically, page and half-page scrolling
* commands moved to the first non-blank character in the new line. If
* the line changes because of the scroll, we do that as well, but if the
* line doesn't change because the line is so large that the scroll happened
* inside of the line, we leave the cursor alone.
*/
/*
* v_hpageup -- [count]^U
* Page up half screens.
*/
int
v_hpageup(sp, ep, vp, fm, tm, rp)
SCR *sp;
EXF *ep;
VICMDARG *vp;
MARK *fm, *tm, *rp;
{
/*
* Half screens always succeed unless already at SOF. Half screens
* set the scroll value, even if the command ultimately failed, in
* historic vi. It's probably a don't care.
*/
if (F_ISSET(vp, VC_C1SET))
O_VAL(sp, O_SCROLL) = vp->count;
else
vp->count = O_VAL(sp, O_SCROLL);
if (sp->s_down(sp, ep, rp, (recno_t)O_VAL(sp, O_SCROLL), 1))
return (1);
if (rp->lno != fm->lno && nonblank(sp, ep, rp->lno, &rp->cno))
return (1);
return (0);
}
/*
* v_hpagedown -- [count]^D
* Page down half screens.
*/
int
v_hpagedown(sp, ep, vp, fm, tm, rp)
SCR *sp;
EXF *ep;
VICMDARG *vp;
MARK *fm, *tm, *rp;
{
/*
* Half screens always succeed unless already at EOF. Half screens
* set the scroll value, even if the command ultimately failed, in
* historic vi. It's probably a don't care.
*/
if (F_ISSET(vp, VC_C1SET))
O_VAL(sp, O_SCROLL) = vp->count;
else
vp->count = O_VAL(sp, O_SCROLL);
if (sp->s_up(sp, ep, rp, (recno_t)O_VAL(sp, O_SCROLL), 1))
return (1);
if (rp->lno != fm->lno && nonblank(sp, ep, rp->lno, &rp->cno))
return (1);
return (0);
}
/*
* v_pageup -- [count]^B
* Page up full screens.
*/
int
v_pageup(sp, ep, vp, fm, tm, rp)
SCR *sp;
EXF *ep;
VICMDARG *vp;
MARK *fm, *tm, *rp;
{
recno_t count;
/* Calculation from POSIX 1003.2/D8. */
count = (F_ISSET(vp, VC_C1SET) ? vp->count : 1) * (sp->t_rows - 1);
if (sp->s_down(sp, ep, rp, count, 1))
return (1);
if (rp->lno != fm->lno && nonblank(sp, ep, rp->lno, &rp->cno))
return (1);
return (0);
}
/*
* v_pagedown -- [count]^F
* Page down full screens.
*/
int
v_pagedown(sp, ep, vp, fm, tm, rp)
SCR *sp;
EXF *ep;
VICMDARG *vp;
MARK *fm, *tm, *rp;
{
recno_t count;
/* Calculation from POSIX 1003.2/D8. */
count = (F_ISSET(vp, VC_C1SET) ? vp->count : 1) * (sp->t_rows - 1);
if (sp->s_up(sp, ep, rp, count, 1))
return (1);
if (rp->lno != fm->lno && nonblank(sp, ep, rp->lno, &rp->cno))
return (1);
return (0);
}
/*
* v_lineup -- [count]^Y
* Page up by lines.
*/
int
v_lineup(sp, ep, vp, fm, tm, rp)
SCR *sp;
EXF *ep;
VICMDARG *vp;
MARK *fm, *tm, *rp;
{
/*
* The cursor moves down, staying with its original line, unless it
* reaches the bottom of the screen.
*/
return (sp->s_down(sp, ep,
rp, F_ISSET(vp, VC_C1SET) ? vp->count : 1, 0));
}
/*
* v_linedown -- [count]^E
* Page down by lines.
*/
int
v_linedown(sp, ep, vp, fm, tm, rp)
SCR *sp;
EXF *ep;
VICMDARG *vp;
MARK *fm, *tm, *rp;
{
/*
* The cursor moves up, staying with its original line, unless it
* reaches the top of the screen.
*/
return (sp->s_up(sp, ep,
rp, F_ISSET(vp, VC_C1SET) ? vp->count : 1, 0));
}