contrib/nvi2/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 10.10 2001/06/25 15:19:32 skimo Exp $";
  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(SCR *, VICMD *);
  65  */
  66 int
  67 v_paragraphf(SCR *sp, VICMD *vp)
  68 {
  69         enum { P_INTEXT, P_INBLANK } pstate;
  70         size_t lastlen, len;
  71         recno_t cnt, lastlno, lno;
  72         int isempty;
  73         CHAR_T *p;
  74         char *lp;
  75
  76         /*
  77          * !!!
  78          * If the starting cursor position is at or before any non-blank
  79          * characters in the line, i.e. the movement is cutting all of the
  80          * line's text, the buffer is in line mode.  It's a lot easier to
  81          * check here, because we know that the end is going to be the start
  82          * or end of a line.
  83          *
  84          * This was historical practice in vi, with a single exception.  If
  85          * the paragraph movement was from the start of the last line to EOF,
  86          * then all the characters were deleted from the last line, but the
  87          * line itself remained.  If somebody complains, don't pause, don't
  88          * hesitate, just hit them.
  89          */
  90         if (ISMOTION(vp))
  91                 if (vp->m_start.cno == 0)
  92                         F_SET(vp, VM_LMODE);
  93                 else {
  94                         vp->m_stop = vp->m_start;
  95                         vp->m_stop.cno = 0;
  96                         if (nonblank(sp, vp->m_stop.lno, &vp->m_stop.cno))
  97                                 return (1);
  98                         if (vp->m_start.cno <= vp->m_stop.cno)
  99                                 F_SET(vp, VM_LMODE);
 100                 }
 101
 102         /* Figure out what state we're currently in. */
 103         lno = vp->m_start.lno;
 104         if (db_get(sp, lno, 0, &p, &len))
 105                 goto eof;
 106
 107         /*
 108          * If we start in text, we want to switch states
 109          * (2 * N - 1) times, in non-text, (2 * N) times.
 110          */
 111         cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
 112         cnt *= 2;
 113         if (len == 0 || v_isempty(p, len))
 114                 pstate = P_INBLANK;
 115         else {
 116                 --cnt;
 117                 pstate = P_INTEXT;
 118         }
 119
 120         for (;;) {
 121                 lastlno = lno;
 122                 lastlen = len;
 123                 if (db_get(sp, ++lno, 0, &p, &len))
 124                         goto eof;
 125                 switch (pstate) {
 126                 case P_INTEXT:
 127                         INTEXT_CHECK;
 128                         break;
 129                 case P_INBLANK:
 130                         if (len == 0 || v_isempty(p, len))
 131                                 break;
 132                         if (--cnt) {
 133                                 pstate = P_INTEXT;
 134                                 break;
 135                         }
 136                         /*
 137                          * !!!
 138                          * Non-motion commands move to the end of the range,
 139                          * delete and yank stay at the start.  Ignore others.
 140                          * Adjust the end of the range for motion commands;
 141                          * historically, a motion component was to the end of
 142                          * the previous line, whereas the movement command was
 143                          * to the start of the new "paragraph".
 144                          */
 145 found:                  if (ISMOTION(vp)) {
 146                                 vp->m_stop.lno = lastlno;
 147                                 vp->m_stop.cno = lastlen ? lastlen - 1 : 0;
 148                                 vp->m_final = vp->m_start;
 149                         } else {
 150                                 vp->m_stop.lno = lno;
 151                                 vp->m_stop.cno = 0;
 152                                 vp->m_final = vp->m_stop;
 153                         }
 154                         return (0);
 155                 default:
 156                         abort();
 157                 }
 158         }
 159
 160         /*
 161          * !!!
 162          * Adjust end of the range for motion commands; EOF is a movement
 163          * sink.  The } command historically moved to the end of the last
 164          * line, not the beginning, from any position before the end of the
 165          * last line.  It also historically worked on empty files, so we
 166          * have to make it okay.
 167          */
 168 eof:    if (vp->m_start.lno == lno || vp->m_start.lno == lno - 1) {
 169                 if (db_eget(sp, vp->m_start.lno, &p, &len, &isempty)) {
 170                         if (!isempty)
 171                                 return (1);
 172                         vp->m_start.cno = 0;
 173                         return (0);
 174                 }
 175                 if (vp->m_start.cno == (len ? len - 1 : 0)) {
 176                         v_eof(sp, NULL);
 177                         return (1);
 178                 }
 179         }
 180         /*
 181          * !!!
 182          * Non-motion commands move to the end of the range, delete
 183          * and yank stay at the start.  Ignore others.
 184          *
 185          * If deleting the line (which happens if deleting to EOF), then
 186          * cursor movement is to the first nonblank.
 187          */
 188         if (ISMOTION(vp) && ISCMD(vp->rkp, 'd')) {
 189                 F_CLR(vp, VM_RCM_MASK);
 190                 F_SET(vp, VM_RCM_SETFNB);
 191         }
 192         vp->m_stop.lno = lno - 1;
 193         vp->m_stop.cno = len ? len - 1 : 0;
 194         vp->m_final = ISMOTION(vp) ? vp->m_start : vp->m_stop;
 195         return (0);
 196 }
 197
 198 /*
 199  * v_paragraphb -- [count]{
 200  *      Move backward count paragraphs.
 201  *
 202  * PUBLIC: int v_paragraphb(SCR *, VICMD *);
 203  */
 204 int
 205 v_paragraphb(SCR *sp, VICMD *vp)
 206 {
 207         enum { P_INTEXT, P_INBLANK } pstate;
 208         size_t len;
 209         recno_t cnt, lno;
 210         CHAR_T *p;
 211         char *lp;
 212
 213         /*
 214          * !!!
 215          * Check for SOF.  The historic vi didn't complain if users hit SOF
 216          * repeatedly, unless it was part of a motion command.  There is no
 217          * question but that Emerson's editor of choice was vi.
 218          *
 219          * The { command historically moved to the beginning of the first
 220          * line if invoked on the first line.
 221          *
 222          * !!!
 223          * If the starting cursor position is in the first column (backward
 224          * paragraph movements did NOT historically pay attention to non-blank
 225          * characters) i.e. the movement is cutting the entire line, the buffer
 226          * is in line mode.  Cuts from the beginning of the line also did not
 227          * cut the current line, but started at the previous EOL.
 228          *
 229          * Correct for a left motion component while we're thinking about it.
 230          */
 231         lno = vp->m_start.lno;
 232
 233         if (ISMOTION(vp))
 234                 if (vp->m_start.cno == 0) {
 235                         if (vp->m_start.lno == 1) {
 236                                 v_sof(sp, &vp->m_start);
 237                                 return (1);
 238                         } else
 239                                 --vp->m_start.lno;
 240                         F_SET(vp, VM_LMODE);
 241                 } else
 242                         --vp->m_start.cno;
 243
 244         if (vp->m_start.lno <= 1)
 245                 goto sof;
 246
 247         /* Figure out what state we're currently in. */
 248         if (db_get(sp, lno, 0, &p, &len))
 249                 goto sof;
 250
 251         /*
 252          * If we start in text, we want to switch states
 253          * (2 * N - 1) times, in non-text, (2 * N) times.
 254          */
 255         cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
 256         cnt *= 2;
 257         if (len == 0 || v_isempty(p, len))
 258                 pstate = P_INBLANK;
 259         else {
 260                 --cnt;
 261                 pstate = P_INTEXT;
 262
 263                 /*
 264                  * !!!
 265                  * If the starting cursor is past the first column,
 266                  * the current line is checked for a paragraph.
 267                  */
 268                 if (vp->m_start.cno > 0)
 269                         ++lno;
 270         }
 271
 272         for (;;) {
 273                 if (db_get(sp, --lno, 0, &p, &len))
 274                         goto sof;
 275                 switch (pstate) {
 276                 case P_INTEXT:
 277                         INTEXT_CHECK;
 278                         break;
 279                 case P_INBLANK:
 280                         if (len != 0 && !v_isempty(p, len)) {
 281                                 if (!--cnt)
 282                                         goto found;
 283                                 pstate = P_INTEXT;
 284                         }
 285                         break;
 286                 default:
 287                         abort();
 288                 }
 289         }
 290
 291         /* SOF is a movement sink. */
 292 sof:    lno = 1;
 293
 294 found:  vp->m_stop.lno = lno;
 295         vp->m_stop.cno = 0;
 296
 297         /*
 298          * All commands move to the end of the range.  (We already
 299          * adjusted the start of the range for motion commands).
 300          */
 301         vp->m_final = vp->m_stop;
 302         return (0);
 303 }
 304
 305 /*
 306  * v_buildps --
 307  *      Build the paragraph command search pattern.
 308  *
 309  * PUBLIC: int v_buildps(SCR *, char *, char *);
 310  */
 311 int
 312 v_buildps(SCR *sp, char *p_p, char *s_p)
 313 {
 314         VI_PRIVATE *vip;
 315         size_t p_len, s_len;
 316         char *p;
 317
 318         /*
 319          * The vi paragraph command searches for either a paragraph or
 320          * section option macro.
 321          */
 322         p_len = p_p == NULL ? 0 : strlen(p_p);
 323         s_len = s_p == NULL ? 0 : strlen(s_p);
 324
 325         if (p_len == 0 && s_len == 0)
 326                 return (0);
 327
 328         MALLOC_RET(sp, p, char *, p_len + s_len + 1);
 329
 330         vip = VIP(sp);
 331         if (vip->ps != NULL)
 332                 free(vip->ps);
 333
 334         if (p_p != NULL)
 335                 memmove(p, p_p, p_len + 1);
 336         if (s_p != NULL)
 337                 memmove(p + p_len, s_p, s_len + 1);
 338         vip->ps = p;
 339         return (0);
 340 }