freebsd-src/contrib/nvi/ex/ex_shift.c
Peter Wemm b8ba871bd9 Import of nvi-1.79, minus a few bits that we dont need (eg: postscript
files, curses, db, regex etc that we already have).  The other glue will
follow shortly.

Obtained from: Keith Bostic <bostic@bostic.com>
1996-11-01 06:45:43 +00:00

192 lines
4.5 KiB
C

/*-
* Copyright (c) 1992, 1993, 1994
* The Regents of the University of California. All rights reserved.
* Copyright (c) 1992, 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[] = "@(#)ex_shift.c 10.11 (Berkeley) 9/15/96";
#endif /* not lint */
#include <sys/types.h>
#include <sys/queue.h>
#include <bitstring.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "../common/common.h"
enum which {LEFT, RIGHT};
static int shift __P((SCR *, EXCMD *, enum which));
/*
* ex_shiftl -- :<[<...]
*
*
* PUBLIC: int ex_shiftl __P((SCR *, EXCMD *));
*/
int
ex_shiftl(sp, cmdp)
SCR *sp;
EXCMD *cmdp;
{
return (shift(sp, cmdp, LEFT));
}
/*
* ex_shiftr -- :>[>...]
*
* PUBLIC: int ex_shiftr __P((SCR *, EXCMD *));
*/
int
ex_shiftr(sp, cmdp)
SCR *sp;
EXCMD *cmdp;
{
return (shift(sp, cmdp, RIGHT));
}
/*
* shift --
* Ex shift support.
*/
static int
shift(sp, cmdp, rl)
SCR *sp;
EXCMD *cmdp;
enum which rl;
{
recno_t from, to;
size_t blen, len, newcol, newidx, oldcol, oldidx, sw;
int curset;
char *p, *bp, *tbp;
NEEDFILE(sp, cmdp);
if (O_VAL(sp, O_SHIFTWIDTH) == 0) {
msgq(sp, M_INFO, "152|shiftwidth option set to 0");
return (0);
}
/* Copy the lines being shifted into the unnamed buffer. */
if (cut(sp, NULL, &cmdp->addr1, &cmdp->addr2, CUT_LINEMODE))
return (1);
/*
* The historic version of vi permitted the user to string any number
* of '>' or '<' characters together, resulting in an indent of the
* appropriate levels. There's a special hack in ex_cmd() so that
* cmdp->argv[0] points to the string of '>' or '<' characters.
*
* Q: What's the difference between the people adding features
* to vi and the Girl Scouts?
* A: The Girl Scouts have mint cookies and adult supervision.
*/
for (p = cmdp->argv[0]->bp, sw = 0; *p == '>' || *p == '<'; ++p)
sw += O_VAL(sp, O_SHIFTWIDTH);
GET_SPACE_RET(sp, bp, blen, 256);
curset = 0;
for (from = cmdp->addr1.lno, to = cmdp->addr2.lno; from <= to; ++from) {
if (db_get(sp, from, DBG_FATAL, &p, &len))
goto err;
if (!len) {
if (sp->lno == from)
curset = 1;
continue;
}
/*
* Calculate the old indent amount and the number of
* characters it used.
*/
for (oldidx = 0, oldcol = 0; oldidx < len; ++oldidx)
if (p[oldidx] == ' ')
++oldcol;
else if (p[oldidx] == '\t')
oldcol += O_VAL(sp, O_TABSTOP) -
oldcol % O_VAL(sp, O_TABSTOP);
else
break;
/* Calculate the new indent amount. */
if (rl == RIGHT)
newcol = oldcol + sw;
else {
newcol = oldcol < sw ? 0 : oldcol - sw;
if (newcol == oldcol) {
if (sp->lno == from)
curset = 1;
continue;
}
}
/* Get a buffer that will hold the new line. */
ADD_SPACE_RET(sp, bp, blen, newcol + len);
/*
* Build a new indent string and count the number of
* characters it uses.
*/
for (tbp = bp, newidx = 0;
newcol >= O_VAL(sp, O_TABSTOP); ++newidx) {
*tbp++ = '\t';
newcol -= O_VAL(sp, O_TABSTOP);
}
for (; newcol > 0; --newcol, ++newidx)
*tbp++ = ' ';
/* Add the original line. */
memcpy(tbp, p + oldidx, len - oldidx);
/* Set the replacement line. */
if (db_set(sp, from, bp, (tbp + (len - oldidx)) - bp)) {
err: FREE_SPACE(sp, bp, blen);
return (1);
}
/*
* !!!
* The shift command in historic vi had the usual bizarre
* collection of cursor semantics. If called from vi, the
* cursor was repositioned to the first non-blank character
* of the lowest numbered line shifted. If called from ex,
* the cursor was repositioned to the first non-blank of the
* highest numbered line shifted. Here, if the cursor isn't
* part of the set of lines that are moved, move it to the
* first non-blank of the last line shifted. (This makes
* ":3>>" in vi work reasonably.) If the cursor is part of
* the shifted lines, it doesn't get moved at all. This
* permits shifting of marked areas, i.e. ">'a." shifts the
* marked area twice, something that couldn't be done with
* historic vi.
*/
if (sp->lno == from) {
curset = 1;
if (newidx > oldidx)
sp->cno += newidx - oldidx;
else if (sp->cno >= oldidx - newidx)
sp->cno -= oldidx - newidx;
}
}
if (!curset) {
sp->lno = to;
sp->cno = 0;
(void)nonblank(sp, to, &sp->cno);
}
FREE_SPACE(sp, bp, blen);
sp->rptlines[L_SHIFT] += cmdp->addr2.lno - cmdp->addr1.lno + 1;
return (0);
}