dist/nvi/ex/ex_shift.c

   1 /*      $NetBSD: ex_shift.c,v 1.2 2008/12/12 22:55:56 lukem Exp $ */
   2
   3 /*-
   4  * Copyright (c) 1992, 1993, 1994
   5  *      The Regents of the University of California.  All rights reserved.
   6  * Copyright (c) 1992, 1993, 1994, 1995, 1996
   7  *      Keith Bostic.  All rights reserved.
   8  *
   9  * See the LICENSE file for redistribution information.
  10  */
  11
  12 #include "config.h"
  13
  14 #ifndef lint
  15 static const char sccsid[] = "Id: ex_shift.c,v 10.17 2001/06/25 15:19:20 skimo Exp (Berkeley) Date: 2001/06/25 15:19:20";
  16 #endif /* not lint */
  17
  18 #include <sys/types.h>
  19 #include <sys/queue.h>
  20
  21 #include <bitstring.h>
  22 #include <limits.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26
  27 #include "../common/common.h"
  28
  29 enum which {LEFT, RIGHT};
  30 static int shift __P((SCR *, EXCMD *, enum which));
  31
  32 /*
  33  * ex_shiftl -- :<[<...]
  34  *
  35  *
  36  * PUBLIC: int ex_shiftl __P((SCR *, EXCMD *));
  37  */
  38 int
  39 ex_shiftl(SCR *sp, EXCMD *cmdp)
  40 {
  41         return (shift(sp, cmdp, LEFT));
  42 }
  43
  44 /*
  45  * ex_shiftr -- :>[>...]
  46  *
  47  * PUBLIC: int ex_shiftr __P((SCR *, EXCMD *));
  48  */
  49 int
  50 ex_shiftr(SCR *sp, EXCMD *cmdp)
  51 {
  52         return (shift(sp, cmdp, RIGHT));
  53 }
  54
  55 /*
  56  * shift --
  57  *      Ex shift support.
  58  */
  59 static int
  60 shift(SCR *sp, EXCMD *cmdp, enum which rl)
  61 {
  62         db_recno_t from, to;
  63         size_t blen, len, newcol, newidx, oldcol, oldidx, sw;
  64         int curset;
  65         CHAR_T *p;
  66         CHAR_T *bp, *tbp;
  67
  68         NEEDFILE(sp, cmdp);
  69
  70         if (O_VAL(sp, O_SHIFTWIDTH) == 0) {
  71                 msgq(sp, M_INFO, "152|shiftwidth option set to 0");
  72                 return (0);
  73         }
  74
  75         /* Copy the lines being shifted into the unnamed buffer. */
  76         if (cut(sp, NULL, &cmdp->addr1, &cmdp->addr2, CUT_LINEMODE))
  77                 return (1);
  78
  79         /*
  80          * The historic version of vi permitted the user to string any number
  81          * of '>' or '<' characters together, resulting in an indent of the
  82          * appropriate levels.  There's a special hack in ex_cmd() so that
  83          * cmdp->argv[0] points to the string of '>' or '<' characters.
  84          *
  85          * Q: What's the difference between the people adding features
  86          *    to vi and the Girl Scouts?
  87          * A: The Girl Scouts have mint cookies and adult supervision.
  88          */
  89         for (p = cmdp->argv[0]->bp, sw = 0; *p == '>' || *p == '<'; ++p)
  90                 sw += O_VAL(sp, O_SHIFTWIDTH);
  91
  92         GET_SPACE_RETW(sp, bp, blen, 256);
  93
  94         curset = 0;
  95         for (from = cmdp->addr1.lno, to = cmdp->addr2.lno; from <= to; ++from) {
  96                 if (db_get(sp, from, DBG_FATAL, &p, &len))
  97                         goto err;
  98                 if (!len) {
  99                         if (sp->lno == from)
 100                                 curset = 1;
 101                         continue;
 102                 }
 103
 104                 /*
 105                  * Calculate the old indent amount and the number of
 106                  * characters it used.
 107                  */
 108                 for (oldidx = 0, oldcol = 0; oldidx < len; ++oldidx)
 109                         if (p[oldidx] == ' ')
 110                                 ++oldcol;
 111                         else if (p[oldidx] == '\t')
 112                                 oldcol += O_VAL(sp, O_TABSTOP) -
 113                                     oldcol % O_VAL(sp, O_TABSTOP);
 114                         else
 115                                 break;
 116
 117                 /* Calculate the new indent amount. */
 118                 if (rl == RIGHT)
 119                         newcol = oldcol + sw;
 120                 else {
 121                         newcol = oldcol < sw ? 0 : oldcol - sw;
 122                         if (newcol == oldcol) {
 123                                 if (sp->lno == from)
 124                                         curset = 1;
 125                                 continue;
 126                         }
 127                 }
 128
 129                 /* Get a buffer that will hold the new line. */
 130                 ADD_SPACE_RETW(sp, bp, blen, newcol + len);
 131
 132                 /*
 133                  * Build a new indent string and count the number of
 134                  * characters it uses.
 135                  */
 136                 tbp = bp;
 137                 newidx = 0;
 138                 if (!O_ISSET(sp, O_EXPANDTAB)) {
 139                         for (; newcol >= O_VAL(sp, O_TABSTOP); ++newidx) {
 140                                 *tbp++ = '\t';
 141                                 newcol -= O_VAL(sp, O_TABSTOP);
 142                         }
 143                 }
 144                 for (; newcol > 0; --newcol, ++newidx)
 145                         *tbp++ = ' ';
 146
 147                 /* Add the original line. */
 148                 MEMCPYW(tbp, p + oldidx, len - oldidx);
 149
 150                 /* Set the replacement line. */
 151                 if (db_set(sp, from, bp, (tbp + (len - oldidx)) - bp)) {
 152 err:                    FREE_SPACEW(sp, bp, blen);
 153                         return (1);
 154                 }
 155
 156                 /*
 157                  * !!!
 158                  * The shift command in historic vi had the usual bizarre
 159                  * collection of cursor semantics.  If called from vi, the
 160                  * cursor was repositioned to the first non-blank character
 161                  * of the lowest numbered line shifted.  If called from ex,
 162                  * the cursor was repositioned to the first non-blank of the
 163                  * highest numbered line shifted.  Here, if the cursor isn't
 164                  * part of the set of lines that are moved, move it to the
 165                  * first non-blank of the last line shifted.  (This makes
 166                  * ":3>>" in vi work reasonably.)  If the cursor is part of
 167                  * the shifted lines, it doesn't get moved at all.  This
 168                  * permits shifting of marked areas, i.e. ">'a." shifts the
 169                  * marked area twice, something that couldn't be done with
 170                  * historic vi.
 171                  */
 172                 if (sp->lno == from) {
 173                         curset = 1;
 174                         if (newidx > oldidx)
 175                                 sp->cno += newidx - oldidx;
 176                         else if (sp->cno >= oldidx - newidx)
 177                                 sp->cno -= oldidx - newidx;
 178                 }
 179         }
 180         if (!curset) {
 181                 sp->lno = to;
 182                 sp->cno = 0;
 183                 (void)nonblank(sp, to, &sp->cno);
 184         }
 185
 186         FREE_SPACEW(sp, bp, blen);
 187
 188         sp->rptlines[L_SHIFT] += cmdp->addr2.lno - cmdp->addr1.lno + 1;
 189         return (0);
 190 }