dist/nvi/vi/v_match.c

   1 /*      $NetBSD: v_match.c,v 1.3 2008/12/05 22:51:43 christos 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: v_match.c,v 10.10 2001/06/25 15:19:32 skimo Exp (Berkeley) Date: 2001/06/25 15:19:32";
  16 #endif /* not lint */
  17
  18 #include <sys/types.h>
  19 #include <sys/queue.h>
  20 #include <sys/time.h>
  21
  22 #include <bitstring.h>
  23 #include <limits.h>
  24 #include <stdio.h>
  25 #include <string.h>
  26
  27 #include "../common/common.h"
  28 #include "vi.h"
  29
  30 /*
  31  * v_match -- %
  32  *      Search to matching character.
  33  *
  34  * PUBLIC: int v_match __P((SCR *, VICMD *));
  35  */
  36 int
  37 v_match(SCR *sp, VICMD *vp)
  38 {
  39         VCS cs;
  40         MARK *mp;
  41         size_t cno, len, off;
  42         int cnt, isempty, matchc, startc, (*gc)__P((SCR *, VCS *));
  43         CHAR_T *p;
  44         char *cp;
  45         const char *match_chars;
  46
  47         static MARK match = { 0, 0 };
  48         static int match_dir;
  49
  50         /*
  51          * Historically vi would match (), {} and [] however
  52          * an update included <>.  This is ok for editing HTML
  53          * but a pain in the butt for C source.
  54          * Making it an option lets the user decide what is 'right'.
  55          * Also fixed to do something sensible with "".
  56          */
  57         match_chars = O_STR(sp, O_MATCHCHARS);
  58
  59         /*
  60          * !!!
  61          * Historic practice; ignore the count.
  62          *
  63          * !!!
  64          * Historical practice was to search for the initial character in the
  65          * forward direction only.
  66          */
  67         if (db_eget(sp, vp->m_start.lno, &p, &len, &isempty)) {
  68                 if (isempty)
  69                         goto nomatch;
  70                 return (1);
  71         }
  72         for (off = vp->m_start.cno;; ++off) {
  73                 if (off >= len) {
  74 nomatch:                msgq(sp, M_BERR, "184|No match character on this line");
  75                         return (1);
  76                 }
  77                 startc = p[off];
  78                 cp = strchr(match_chars, startc);
  79                 if (cp != NULL)
  80                         break;
  81         }
  82         cnt = cp - match_chars;
  83         matchc = match_chars[cnt ^ 1];
  84
  85         /* Alternate back-forward search if startc and matchc the same */
  86         if (startc == matchc) {
  87                 /* are we continuing from where last match finished? */
  88                 if (match.lno == vp->m_start.lno && match.cno ==vp->m_start.cno)
  89                         /* yes - continue in sequence */
  90                         match_dir++;
  91                 else
  92                         /* no - go forward, back, back, forward */
  93                         match_dir = 1;
  94                 if (match_dir & 2)
  95                         cnt++;
  96         }
  97         gc = cnt & 1 ? cs_prev : cs_next;
  98
  99         cs.cs_lno = vp->m_start.lno;
 100         cs.cs_cno = off;
 101         if (cs_init(sp, &cs))
 102                 return (1);
 103         for (cnt = 1;;) {
 104                 if (gc(sp, &cs))
 105                         return (1);
 106                 if (cs.cs_flags != 0) {
 107                         if (cs.cs_flags == CS_EOF || cs.cs_flags == CS_SOF)
 108                                 break;
 109                         continue;
 110                 }
 111                 if (cs.cs_ch == matchc && --cnt == 0)
 112                         break;
 113                 if (cs.cs_ch == startc)
 114                         ++cnt;
 115         }
 116         if (cnt) {
 117                 msgq(sp, M_BERR, "185|Matching character not found");
 118                 return (1);
 119         }
 120
 121         vp->m_stop.lno = cs.cs_lno;
 122         vp->m_stop.cno = cs.cs_cno;
 123
 124         /*
 125          * If moving right, non-motion commands move to the end of the range.
 126          * Delete and yank stay at the start.
 127          *
 128          * If moving left, all commands move to the end of the range.
 129          *
 130          * !!!
 131          * Don't correct for leftward movement -- historic vi deleted the
 132          * starting cursor position when deleting to a match.
 133          */
 134         if (vp->m_start.lno < vp->m_stop.lno ||
 135             (vp->m_start.lno == vp->m_stop.lno &&
 136             vp->m_start.cno < vp->m_stop.cno))
 137                 vp->m_final = ISMOTION(vp) ? vp->m_start : vp->m_stop;
 138         else
 139                 vp->m_final = vp->m_stop;
 140
 141         match.lno = vp->m_final.lno;
 142         match.cno = vp->m_final.cno;
 143
 144         /*
 145          * !!!
 146          * If the motion is across lines, and the earliest cursor position
 147          * is at or before any non-blank characters in the line, i.e. the
 148          * movement is cutting all of the line's text, and the later cursor
 149          * position has nothing other than whitespace characters between it
 150          * and the end of its line, the buffer is in line mode.
 151          */
 152         if (!ISMOTION(vp) || vp->m_start.lno == vp->m_stop.lno)
 153                 return (0);
 154         mp = vp->m_start.lno < vp->m_stop.lno ? &vp->m_start : &vp->m_stop;
 155         if (mp->cno != 0) {
 156                 cno = 0;
 157                 if (nonblank(sp, mp->lno, &cno))
 158                         return (1);
 159                 if (cno < mp->cno)
 160                         return (0);
 161         }
 162         mp = vp->m_start.lno < vp->m_stop.lno ? &vp->m_stop : &vp->m_start;
 163         if (db_get(sp, mp->lno, DBG_FATAL, &p, &len))
 164                 return (1);
 165         for (p += mp->cno + 1, len -= mp->cno; --len; ++p)
 166                 if (!isblank(*p))
 167                         return (0);
 168         F_SET(vp, VM_LMODE);
 169         return (0);
 170 }