vi/v_sentence.c

   1 /*-
   2  * Copyright (c) 1992, 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  * Copyright (c) 1992, 1993, 1994, 1995, 1996
   5  *      Keith Bostic.  All rights reserved.
   6  *
   7  * See the LICENSE file for redistribution information.
   8  */
   9
  10 #include "config.h"
  11
  12 #ifndef lint
  13 static const char sccsid[] = "$Id: v_sentence.c,v 10.9 2001/06/25 15:19:35 skimo Exp $ (Berkeley) $Date: 2001/06/25 15:19:35 $";
  14 #endif /* not lint */
  15
  16 #include <sys/types.h>
  17 #include <sys/queue.h>
  18 #include <sys/time.h>
  19
  20 #include <bitstring.h>
  21 #include <ctype.h>
  22 #include <limits.h>
  23 #include <stdio.h>
  24
  25 #include "../common/common.h"
  26 #include "vi.h"
  27
  28 /*
  29  * !!!
  30  * In historic vi, a sentence was delimited by a '.', '?' or '!' character
  31  * followed by TWO spaces or a newline.  One or more empty lines was also
  32  * treated as a separate sentence.  The Berkeley documentation for historical
  33  * vi states that any number of ')', ']', '"' and '\'' characters can be
  34  * between the delimiter character and the spaces or end of line, however,
  35  * the historical implementation did not handle additional '"' characters.
  36  * We follow the documentation here, not the implementation.
  37  *
  38  * Once again, historical vi didn't do sentence movements associated with
  39  * counts consistently, mostly in the presence of lines containing only
  40  * white-space characters.
  41  *
  42  * This implementation also permits a single tab to delimit sentences, and
  43  * treats lines containing only white-space characters as empty lines.
  44  * Finally, tabs are eaten (along with spaces) when skipping to the start
  45  * of the text following a "sentence".
  46  */
  47
  48 /*
  49  * v_sentencef -- [count])
  50  *      Move forward count sentences.
  51  *
  52  * PUBLIC: int v_sentencef __P((SCR *, VICMD *));
  53  */
  54 int
  55 v_sentencef(SCR *sp, VICMD *vp)
  56 {
  57         enum { BLANK, NONE, PERIOD } state;
  58         VCS cs;
  59         size_t len;
  60         u_long cnt;
  61
  62         cs.cs_lno = vp->m_start.lno;
  63         cs.cs_cno = vp->m_start.cno;
  64         if (cs_init(sp, &cs))
  65                 return (1);
  66
  67         cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
  68
  69         /*
  70          * !!!
  71          * If in white-space, the next start of sentence counts as one.
  72          * This may not handle "  .  " correctly, but it's real unclear
  73          * what correctly means in that case.
  74          */
  75         if (cs.cs_flags == CS_EMP || cs.cs_flags == 0 && isblank(cs.cs_ch)) {
  76                 if (cs_fblank(sp, &cs))
  77                         return (1);
  78                 if (--cnt == 0) {
  79                         if (vp->m_start.lno != cs.cs_lno ||
  80                             vp->m_start.cno != cs.cs_cno)
  81                                 goto okret;
  82                         return (1);
  83                 }
  84         }
  85
  86         for (state = NONE;;) {
  87                 if (cs_next(sp, &cs))
  88                         return (1);
  89                 if (cs.cs_flags == CS_EOF)
  90                         break;
  91                 if (cs.cs_flags == CS_EOL) {
  92                         if ((state == PERIOD || state == BLANK) && --cnt == 0) {
  93                                 if (cs_next(sp, &cs))
  94                                         return (1);
  95                                 if (cs.cs_flags == 0 &&
  96                                     isblank(cs.cs_ch) && cs_fblank(sp, &cs))
  97                                         return (1);
  98                                 goto okret;
  99                         }
 100                         state = NONE;
 101                         continue;
 102                 }
 103                 if (cs.cs_flags == CS_EMP) {    /* An EMP is two sentences. */
 104                         if (--cnt == 0)
 105                                 goto okret;
 106                         if (cs_fblank(sp, &cs))
 107                                 return (1);
 108                         if (--cnt == 0)
 109                                 goto okret;
 110                         state = NONE;
 111                         continue;
 112                 }
 113                 switch (cs.cs_ch) {
 114                 case '.':
 115                 case '?':
 116                 case '!':
 117                         state = PERIOD;
 118                         break;
 119                 case ')':
 120                 case ']':
 121                 case '"':
 122                 case '\'':
 123                         if (state != PERIOD)
 124                                 state = NONE;
 125                         break;
 126                 case '\t':
 127                         if (state == PERIOD)
 128                                 state = BLANK;
 129                         /* FALLTHROUGH */
 130                 case ' ':
 131                         if (state == PERIOD) {
 132                                 state = BLANK;
 133                                 break;
 134                         }
 135                         if (state == BLANK && --cnt == 0) {
 136                                 if (cs_fblank(sp, &cs))
 137                                         return (1);
 138                                 goto okret;
 139                         }
 140                         /* FALLTHROUGH */
 141                 default:
 142                         state = NONE;
 143                         break;
 144                 }
 145         }
 146
 147         /* EOF is a movement sink, but it's an error not to have moved. */
 148         if (vp->m_start.lno == cs.cs_lno && vp->m_start.cno == cs.cs_cno) {
 149                 v_eof(sp, NULL);
 150                 return (1);
 151         }
 152
 153 okret:  vp->m_stop.lno = cs.cs_lno;
 154         vp->m_stop.cno = cs.cs_cno;
 155
 156         /*
 157          * !!!
 158          * Historic, uh, features, yeah, that's right, call 'em features.
 159          * If the starting and ending cursor positions are at the first
 160          * column in their lines, i.e. the movement is cutting entire lines,
 161          * the buffer is in line mode, and the ending position is the last
 162          * character of the previous line.  Note check to make sure that
 163          * it's not within a single line.
 164          *
 165          * Non-motion commands move to the end of the range.  Delete and
 166          * yank stay at the start.  Ignore others.  Adjust the end of the
 167          * range for motion commands.
 168          */
 169         if (ISMOTION(vp)) {
 170                 if (vp->m_start.cno == 0 &&
 171                     (cs.cs_flags != 0 || vp->m_stop.cno == 0)) {
 172                         if (vp->m_start.lno < vp->m_stop.lno) {
 173                                 if (db_get(sp,
 174                                     --vp->m_stop.lno, DBG_FATAL, NULL, &len))
 175                                         return (1);
 176                                 vp->m_stop.cno = len ? len - 1 : 0;
 177                         }
 178                         F_SET(vp, VM_LMODE);
 179                 } else
 180                         --vp->m_stop.cno;
 181                 vp->m_final = vp->m_start;
 182         } else
 183                 vp->m_final = vp->m_stop;
 184         return (0);
 185 }
 186
 187 /*
 188  * v_sentenceb -- [count](
 189  *      Move backward count sentences.
 190  *
 191  * PUBLIC: int v_sentenceb __P((SCR *, VICMD *));
 192  */
 193 int
 194 v_sentenceb(SCR *sp, VICMD *vp)
 195 {
 196         VCS cs;
 197         db_recno_t slno;
 198         size_t len, scno;
 199         u_long cnt;
 200         int last;
 201
 202         /*
 203          * !!!
 204          * Historic vi permitted the user to hit SOF repeatedly.
 205          */
 206         if (vp->m_start.lno == 1 && vp->m_start.cno == 0)
 207                 return (0);
 208
 209         cs.cs_lno = vp->m_start.lno;
 210         cs.cs_cno = vp->m_start.cno;
 211         if (cs_init(sp, &cs))
 212                 return (1);
 213
 214         cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
 215
 216         /*
 217          * !!!
 218          * In empty lines, skip to the previous non-white-space character.
 219          * If in text, skip to the prevous white-space character.  Believe
 220          * it or not, in the paragraph:
 221          *      ab cd.
 222          *      AB CD.
 223          * if the cursor is on the 'A' or 'B', ( moves to the 'a'.  If it
 224          * is on the ' ', 'C' or 'D', it moves to the 'A'.  Yes, Virginia,
 225          * Berkeley was once a major center of drug activity.
 226          */
 227         if (cs.cs_flags == CS_EMP) {
 228                 if (cs_bblank(sp, &cs))
 229                         return (1);
 230                 for (;;) {
 231                         if (cs_prev(sp, &cs))
 232                                 return (1);
 233                         if (cs.cs_flags != CS_EOL)
 234                                 break;
 235                 }
 236         } else if (cs.cs_flags == 0 && !isblank(cs.cs_ch))
 237                 for (;;) {
 238                         if (cs_prev(sp, &cs))
 239                                 return (1);
 240                         if (cs.cs_flags != 0 || isblank(cs.cs_ch))
 241                                 break;
 242                 }
 243
 244         for (last = 0;;) {
 245                 if (cs_prev(sp, &cs))
 246                         return (1);
 247                 if (cs.cs_flags == CS_SOF)      /* SOF is a movement sink. */
 248                         break;
 249                 if (cs.cs_flags == CS_EOL) {
 250                         last = 1;
 251                         continue;
 252                 }
 253                 if (cs.cs_flags == CS_EMP) {
 254                         if (--cnt == 0)
 255                                 goto ret;
 256                         if (cs_bblank(sp, &cs))
 257                                 return (1);
 258                         last = 0;
 259                         continue;
 260                 }
 261                 switch (cs.cs_ch) {
 262                 case '.':
 263                 case '?':
 264                 case '!':
 265                         if (!last || --cnt != 0) {
 266                                 last = 0;
 267                                 continue;
 268                         }
 269
 270 ret:                    slno = cs.cs_lno;
 271                         scno = cs.cs_cno;
 272
 273                         /*
 274                          * Move to the start of the sentence, skipping blanks
 275                          * and special characters.
 276                          */
 277                         do {
 278                                 if (cs_next(sp, &cs))
 279                                         return (1);
 280                         } while (!cs.cs_flags &&
 281                             (cs.cs_ch == ')' || cs.cs_ch == ']' ||
 282                             cs.cs_ch == '"' || cs.cs_ch == '\''));
 283                         if ((cs.cs_flags || isblank(cs.cs_ch)) &&
 284                             cs_fblank(sp, &cs))
 285                                 return (1);
 286
 287                         /*
 288                          * If it was ".  xyz", with the cursor on the 'x', or
 289                          * "end.  ", with the cursor in the spaces, or the
 290                          * beginning of a sentence preceded by an empty line,
 291                          * we can end up where we started.  Fix it.
 292                          */
 293                         if (vp->m_start.lno != cs.cs_lno ||
 294                             vp->m_start.cno != cs.cs_cno)
 295                                 goto okret;
 296
 297                         /*
 298                          * Well, if an empty line preceded possible blanks
 299                          * and the sentence, it could be a real sentence.
 300                          */
 301                         for (;;) {
 302                                 if (cs_prev(sp, &cs))
 303                                         return (1);
 304                                 if (cs.cs_flags == CS_EOL)
 305                                         continue;
 306                                 if (cs.cs_flags == 0 && isblank(cs.cs_ch))
 307                                         continue;
 308                                 break;
 309                         }
 310                         if (cs.cs_flags == CS_EMP)
 311                                 goto okret;
 312
 313                         /* But it wasn't; try again. */
 314                         ++cnt;
 315                         cs.cs_lno = slno;
 316                         cs.cs_cno = scno;
 317                         last = 0;
 318                         break;
 319                 case '\t':
 320                         last = 1;
 321                         break;
 322                 default:
 323                         last =
 324                             cs.cs_flags == CS_EOL || isblank(cs.cs_ch) ||
 325                             cs.cs_ch == ')' || cs.cs_ch == ']' ||
 326                             cs.cs_ch == '"' || cs.cs_ch == '\'' ? 1 : 0;
 327                 }
 328         }
 329
 330 okret:  vp->m_stop.lno = cs.cs_lno;
 331         vp->m_stop.cno = cs.cs_cno;
 332
 333         /*
 334          * !!!
 335          * If the starting and stopping cursor positions are at the first
 336          * columns in the line, i.e. the movement is cutting an entire line,
 337          * the buffer is in line mode, and the starting position is the last
 338          * character of the previous line.
 339          *
 340          * All commands move to the end of the range.  Adjust the start of
 341          * the range for motion commands.
 342          */
 343         if (ISMOTION(vp))
 344                 if (vp->m_start.cno == 0 &&
 345                     (cs.cs_flags != 0 || vp->m_stop.cno == 0)) {
 346                         if (db_get(sp,
 347                             --vp->m_start.lno, DBG_FATAL, NULL, &len))
 348                                 return (1);
 349                         vp->m_start.cno = len ? len - 1 : 0;
 350                         F_SET(vp, VM_LMODE);
 351                 } else
 352                         --vp->m_start.cno;
 353         vp->m_final = vp->m_stop;
 354         return (0);
 355 }