vi/v_paragraph.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_paragraph.c,v 10.7 1996/03/06 19:54:26 bostic Exp $ (Berkeley) $Date: 1996/03/06 19:54:26 $";
  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 <errno.h>
  22 #include <limits.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26
  27 #include "../common/common.h"
  28 #include "vi.h"
  29
  30 #define INTEXT_CHECK {                                                  \
  31         if (len == 0 || v_isempty(p, len)) {                            \
  32                 if (!--cnt)                                             \
  33                         goto found;                                     \
  34                 pstate = P_INBLANK;                                     \
  35         }                                                               \
  36         /*                                                              \
  37          * !!!                                                          \
  38          * Historic documentation (USD:15-11, 4.2) said that formfeed   \
  39          * characters (^L) in the first column delimited paragraphs.    \
  40          * The historic vi code mentions formfeed characters, but never \
  41          * implements them.  It seems reasonable, do it.                \
  42          */                                                             \
  43         if (p[0] == '\014') {                                           \
  44                 if (!--cnt)                                             \
  45                         goto found;                                     \
  46                 continue;                                               \
  47         }                                                               \
  48         if (p[0] != '.' || len < 2)                                     \
  49                 continue;                                               \
  50         for (lp = VIP(sp)->ps; *lp != '\0'; lp += 2)                    \
  51                 if (lp[0] == p[1] &&                                    \
  52                     (lp[1] == ' ' && len == 2 || lp[1] == p[2]) &&      \
  53                     !--cnt)                                             \
  54                         goto found;                                     \
  55 }
  56
  57 /*
  58  * v_paragraphf -- [count]}
  59  *      Move forward count paragraphs.
  60  *
  61  * Paragraphs are empty lines after text, formfeed characters, or values
  62  * from the paragraph or section options.
  63  *
  64  * PUBLIC: int v_paragraphf __P((SCR *, VICMD *));
  65  */
  66 int
  67 v_paragraphf(sp, vp)
  68         SCR *sp;
  69         VICMD *vp;
  70 {
  71         enum { P_INTEXT, P_INBLANK } pstate;
  72         size_t lastlen, len;
  73         recno_t cnt, lastlno, lno;
  74         int isempty;
  75         char *p, *lp;
  76
  77         /*
  78          * !!!
  79          * If the starting cursor position is at or before any non-blank
  80          * characters in the line, i.e. the movement is cutting all of the
  81          * line's text, the buffer is in line mode.  It's a lot easier to
  82          * check here, because we know that the end is going to be the start
  83          * or end of a line.
  84          *
  85          * This was historical practice in vi, with a single exception.  If
  86          * the paragraph movement was from the start of the last line to EOF,
  87          * then all the characters were deleted from the last line, but the
  88          * line itself remained.  If somebody complains, don't pause, don't
  89          * hesitate, just hit them.
  90          */
  91         if (ISMOTION(vp))
  92                 if (vp->m_start.cno == 0)
  93                         F_SET(vp, VM_LMODE);
  94                 else {
  95                         vp->m_stop = vp->m_start;
  96                         vp->m_stop.cno = 0;
  97                         if (nonblank(sp, vp->m_stop.lno, &vp->m_stop.cno))
  98                                 return (1);
  99                         if (vp->m_start.cno <= vp->m_stop.cno)
 100                                 F_SET(vp, VM_LMODE);
 101                 }
 102
 103         /* Figure out what state we're currently in. */
 104         lno = vp->m_start.lno;
 105         if (db_get(sp, lno, 0, &p, &len))
 106                 goto eof;
 107
 108         /*
 109          * If we start in text, we want to switch states
 110          * (2 * N - 1) times, in non-text, (2 * N) times.
 111          */
 112         cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
 113         cnt *= 2;
 114         if (len == 0 || v_isempty(p, len))
 115                 pstate = P_INBLANK;
 116         else {
 117                 --cnt;
 118                 pstate = P_INTEXT;
 119         }
 120
 121         for (;;) {
 122                 lastlno = lno;
 123                 lastlen = len;
 124                 if (db_get(sp, ++lno, 0, &p, &len))
 125                         goto eof;
 126                 switch (pstate) {
 127                 case P_INTEXT:
 128                         INTEXT_CHECK;
 129                         break;
 130                 case P_INBLANK:
 131                         if (len == 0 || v_isempty(p, len))
 132                                 break;
 133                         if (--cnt) {
 134                                 pstate = P_INTEXT;
 135                                 break;
 136                         }
 137                         /*
 138                          * !!!
 139                          * Non-motion commands move to the end of the range,
 140                          * delete and yank stay at the start.  Ignore others.
 141                          * Adjust the end of the range for motion commands;
 142                          * historically, a motion component was to the end of
 143                          * the previous line, whereas the movement command was
 144                          * to the start of the new "paragraph".
 145                          */
 146 found:                  if (ISMOTION(vp)) {
 147                                 vp->m_stop.lno = lastlno;
 148                                 vp->m_stop.cno = lastlen ? lastlen - 1 : 0;
 149                                 vp->m_final = vp->m_start;
 150                         } else {
 151                                 vp->m_stop.lno = lno;
 152                                 vp->m_stop.cno = 0;
 153                                 vp->m_final = vp->m_stop;
 154                         }
 155                         return (0);
 156                 default:
 157                         abort();
 158                 }
 159         }
 160
 161         /*
 162          * !!!
 163          * Adjust end of the range for motion commands; EOF is a movement
 164          * sink.  The } command historically moved to the end of the last
 165          * line, not the beginning, from any position before the end of the
 166          * last line.  It also historically worked on empty files, so we
 167          * have to make it okay.
 168          */
 169 eof:    if (vp->m_start.lno == lno || vp->m_start.lno == lno - 1) {
 170                 if (db_eget(sp, vp->m_start.lno, &p, &len, &isempty)) {
 171                         if (!isempty)
 172                                 return (1);
 173                         vp->m_start.cno = 0;
 174                         return (0);
 175                 }
 176                 if (vp->m_start.cno == (len ? len - 1 : 0)) {
 177                         v_eof(sp, NULL);
 178                         return (1);
 179                 }
 180         }
 181         /*
 182          * !!!
 183          * Non-motion commands move to the end of the range, delete
 184          * and yank stay at the start.  Ignore others.
 185          *
 186          * If deleting the line (which happens if deleting to EOF), then
 187          * cursor movement is to the first nonblank.
 188          */
 189         if (ISMOTION(vp) && ISCMD(vp->rkp, 'd')) {
 190                 F_CLR(vp, VM_RCM_MASK);
 191                 F_SET(vp, VM_RCM_SETFNB);
 192         }
 193         vp->m_stop.lno = lno - 1;
 194         vp->m_stop.cno = len ? len - 1 : 0;
 195         vp->m_final = ISMOTION(vp) ? vp->m_start : vp->m_stop;
 196         return (0);
 197 }
 198
 199 /*
 200  * v_paragraphb -- [count]{
 201  *      Move backward count paragraphs.
 202  *
 203  * PUBLIC: int v_paragraphb __P((SCR *, VICMD *));
 204  */
 205 int
 206 v_paragraphb(sp, vp)
 207         SCR *sp;
 208         VICMD *vp;
 209 {
 210         enum { P_INTEXT, P_INBLANK } pstate;
 211         size_t len;
 212         recno_t cnt, lno;
 213         char *p, *lp;
 214
 215         /*
 216          * !!!
 217          * Check for SOF.  The historic vi didn't complain if users hit SOF
 218          * repeatedly, unless it was part of a motion command.  There is no
 219          * question but that Emerson's editor of choice was vi.
 220          *
 221          * The { command historically moved to the beginning of the first
 222          * line if invoked on the first line.
 223          *
 224          * !!!
 225          * If the starting cursor position is in the first column (backward
 226          * paragraph movements did NOT historically pay attention to non-blank
 227          * characters) i.e. the movement is cutting the entire line, the buffer
 228          * is in line mode.  Cuts from the beginning of the line also did not
 229          * cut the current line, but started at the previous EOL.
 230          *
 231          * Correct for a left motion component while we're thinking about it.
 232          */
 233         lno = vp->m_start.lno;
 234
 235         if (ISMOTION(vp))
 236                 if (vp->m_start.cno == 0) {
 237                         if (vp->m_start.lno == 1) {
 238                                 v_sof(sp, &vp->m_start);
 239                                 return (1);
 240                         } else
 241                                 --vp->m_start.lno;
 242                         F_SET(vp, VM_LMODE);
 243                 } else
 244                         --vp->m_start.cno;
 245
 246         if (vp->m_start.lno <= 1)
 247                 goto sof;
 248
 249         /* Figure out what state we're currently in. */
 250         if (db_get(sp, lno, 0, &p, &len))
 251                 goto sof;
 252
 253         /*
 254          * If we start in text, we want to switch states
 255          * (2 * N - 1) times, in non-text, (2 * N) times.
 256          */
 257         cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
 258         cnt *= 2;
 259         if (len == 0 || v_isempty(p, len))
 260                 pstate = P_INBLANK;
 261         else {
 262                 --cnt;
 263                 pstate = P_INTEXT;
 264
 265                 /*
 266                  * !!!
 267                  * If the starting cursor is past the first column,
 268                  * the current line is checked for a paragraph.
 269                  */
 270                 if (vp->m_start.cno > 0)
 271                         ++lno;
 272         }
 273
 274         for (;;) {
 275                 if (db_get(sp, --lno, 0, &p, &len))
 276                         goto sof;
 277                 switch (pstate) {
 278                 case P_INTEXT:
 279                         INTEXT_CHECK;
 280                         break;
 281                 case P_INBLANK:
 282                         if (len != 0 && !v_isempty(p, len)) {
 283                                 if (!--cnt)
 284                                         goto found;
 285                                 pstate = P_INTEXT;
 286                         }
 287                         break;
 288                 default:
 289                         abort();
 290                 }
 291         }
 292
 293         /* SOF is a movement sink. */
 294 sof:    lno = 1;
 295
 296 found:  vp->m_stop.lno = lno;
 297         vp->m_stop.cno = 0;
 298
 299         /*
 300          * All commands move to the end of the range.  (We already
 301          * adjusted the start of the range for motion commands).
 302          */
 303         vp->m_final = vp->m_stop;
 304         return (0);
 305 }
 306
 307 /*
 308  * v_buildps --
 309  *      Build the paragraph command search pattern.
 310  *
 311  * PUBLIC: int v_buildps __P((SCR *, char *, char *));
 312  */
 313 int
 314 v_buildps(sp, p_p, s_p)
 315         SCR *sp;
 316         char *p_p, *s_p;
 317 {
 318         VI_PRIVATE *vip;
 319         size_t p_len, s_len;
 320         char *p;
 321
 322         /*
 323          * The vi paragraph command searches for either a paragraph or
 324          * section option macro.
 325          */
 326         p_len = p_p == NULL ? 0 : strlen(p_p);
 327         s_len = s_p == NULL ? 0 : strlen(s_p);
 328
 329         if (p_len == 0 && s_len == 0)
 330                 return (0);
 331
 332         MALLOC_RET(sp, p, char *, p_len + s_len + 1);
 333
 334         vip = VIP(sp);
 335         if (vip->ps != NULL)
 336                 free(vip->ps);
 337
 338         if (p_p != NULL)
 339                 memmove(p, p_p, p_len + 1);
 340         if (s_p != NULL)
 341                 memmove(p + p_len, s_p, s_len + 1);
 342         vip->ps = p;
 343         return (0);
 344 }