contrib/nvi2/ex/ex_txt.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: ex_txt.c,v 10.23 2001/06/25 15:19:21 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 <ctype.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/vi.h"
  29
  30 /*
  31  * !!!
  32  * The backslash characters was special when it preceded a newline as part of
  33  * a substitution replacement pattern.  For example, the input ":a\<cr>" would
  34  * failed immediately with an error, as the <cr> wasn't part of a substitution
  35  * replacement pattern.  This implies a frightening integration of the editor
  36  * and the parser and/or the RE engine.  There's no way I'm going to reproduce
  37  * those semantics.
  38  *
  39  * So, if backslashes are special, this code inserts the backslash and the next
  40  * character into the string, without regard for the character or the command
  41  * being entered.  Since "\<cr>" was illegal historically (except for the one
  42  * special case), and the command will fail eventually, no historical scripts
  43  * should break (presuming they didn't depend on the failure mode itself or the
  44  * characters remaining when failure occurred.
  45  */
  46
  47 static int      txt_dent(SCR *, TEXT *);
  48 static void     txt_prompt(SCR *, TEXT *, ARG_CHAR_T, u_int32_t);
  49
  50 /*
  51  * ex_txt --
  52  *      Get lines from the terminal for ex.
  53  *
  54  * PUBLIC: int ex_txt(SCR *, TEXTH *, ARG_CHAR_T, u_int32_t);
  55  */
  56 int
  57 ex_txt(SCR *sp, TEXTH *tiqh, ARG_CHAR_T prompt, u_int32_t flags)
  58 {
  59         EVENT ev;
  60         GS *gp;
  61         TEXT ait, *ntp, *tp;
  62         carat_t carat_st;
  63         size_t cnt;
  64         int rval;
  65         int nochange;
  66
  67         rval = 0;
  68
  69         /*
  70          * Get a TEXT structure with some initial buffer space, reusing the
  71          * last one if it's big enough.  (All TEXT bookkeeping fields default
  72          * to 0 -- text_init() handles this.)
  73          */
  74         if (!TAILQ_EMPTY(tiqh)) {
  75                 tp = TAILQ_FIRST(tiqh);
  76                 if (TAILQ_NEXT(tp, q) != NULL || tp->lb_len < 32) {
  77                         text_lfree(tiqh);
  78                         goto newtp;
  79                 }
  80                 tp->len = 0;
  81         } else {
  82 newtp:          if ((tp = text_init(sp, NULL, 0, 32)) == NULL)
  83                         goto err;
  84                 TAILQ_INSERT_HEAD(tiqh, tp, q);
  85         }
  86
  87         /* Set the starting line number. */
  88         tp->lno = sp->lno + 1;
  89
  90         /*
  91          * If it's a terminal, set up autoindent, put out the prompt, and
  92          * set it up so we know we were suspended.  Otherwise, turn off
  93          * the autoindent flag, as that requires less special casing below.
  94          *
  95          * XXX
  96          * Historic practice is that ^Z suspended command mode (but, because
  97          * it ran in cooked mode, it was unaffected by the autowrite option.)
  98          * On restart, any "current" input was discarded, whether in insert
  99          * mode or not, and ex was in command mode.  This code matches historic
 100          * practice, but not 'cause it's easier.
 101          */
 102         gp = sp->gp;
 103         if (F_ISSET(gp, G_SCRIPTED))
 104                 LF_CLR(TXT_AUTOINDENT);
 105         else {
 106                 if (LF_ISSET(TXT_AUTOINDENT)) {
 107                         LF_SET(TXT_EOFCHAR);
 108                         if (v_txt_auto(sp, sp->lno, NULL, 0, tp))
 109                                 goto err;
 110                 }
 111                 txt_prompt(sp, tp, prompt, flags);
 112         }
 113
 114         for (carat_st = C_NOTSET, nochange = 0;;) {
 115                 if (v_event_get(sp, &ev, 0, 0))
 116                         goto err;
 117
 118                 /* Deal with all non-character events. */
 119                 switch (ev.e_event) {
 120                 case E_CHARACTER:
 121                         break;
 122                 case E_ERR:
 123                         goto err;
 124                 case E_REPAINT:
 125                 case E_WRESIZE:
 126                         continue;
 127                 case E_EOF:
 128                         rval = 1;
 129                         /* FALLTHROUGH */
 130                 case E_INTERRUPT:
 131                         /*
 132                          * Handle EOF/SIGINT events by discarding partially
 133                          * entered text and returning.  EOF returns failure,
 134                          * E_INTERRUPT returns success.
 135                          */
 136                         goto notlast;
 137                 default:
 138                         v_event_err(sp, &ev);
 139                         goto notlast;
 140                 }
 141
 142                 /*
 143                  * Deal with character events.
 144                  *
 145                  * Check to see if the character fits into the input buffer.
 146                  * (Use tp->len, ignore overwrite and non-printable chars.)
 147                  */
 148                 BINC_GOTOW(sp, tp->lb, tp->lb_len, tp->len + 1);
 149
 150                 switch (ev.e_value) {
 151                 case K_CR:
 152                         /*
 153                          * !!!
 154                          * Historically, <carriage-return>'s in the command
 155                          * weren't special, so the ex parser would return an
 156                          * unknown command error message.  However, if they
 157                          * terminated the command if they were in a map.  I'm
 158                          * pretty sure this still isn't right, but it handles
 159                          * what I've seen so far.
 160                          */
 161                         if (!F_ISSET(&ev.e_ch, CH_MAPPED))
 162                                 goto ins_ch;
 163                         /* FALLTHROUGH */
 164                 case K_NL:
 165                         /*
 166                          * '\' can escape <carriage-return>/<newline>.  We
 167                          * don't discard the backslash because we need it
 168                          * to get the <newline> through the ex parser.
 169                          */
 170                         if (LF_ISSET(TXT_BACKSLASH) &&
 171                             tp->len != 0 && tp->lb[tp->len - 1] == '\\')
 172                                 goto ins_ch;
 173
 174                         /*
 175                          * CR returns from the ex command line.
 176                          *
 177                          * XXX
 178                          * Terminate with a nul, needed by filter.
 179                          */
 180                         if (LF_ISSET(TXT_CR)) {
 181                                 tp->lb[tp->len] = '\0';
 182                                 goto done;
 183                         }
 184
 185                         /*
 186                          * '.' may terminate text input mode; free the current
 187                          * TEXT.
 188                          */
 189                         if (LF_ISSET(TXT_DOTTERM) && tp->len == tp->ai + 1 &&
 190                             tp->lb[tp->len - 1] == '.') {
 191 notlast:                        TAILQ_REMOVE(tiqh, tp, q);
 192                                 text_free(tp);
 193                                 goto done;
 194                         }
 195
 196                         /* Set up bookkeeping for the new line. */
 197                         if ((ntp = text_init(sp, NULL, 0, 32)) == NULL)
 198                                 goto err;
 199                         ntp->lno = tp->lno + 1;
 200
 201                         /*
 202                          * Reset the autoindent line value.  0^D keeps the ai
 203                          * line from changing, ^D changes the level, even if
 204                          * there were no characters in the old line.  Note, if
 205                          * using the current tp structure, use the cursor as
 206                          * the length, the autoindent characters may have been
 207                          * erased.
 208                          */
 209                         if (LF_ISSET(TXT_AUTOINDENT)) {
 210                                 if (nochange) {
 211                                         nochange = 0;
 212                                         if (v_txt_auto(sp,
 213                                             OOBLNO, &ait, ait.ai, ntp))
 214                                                 goto err;
 215                                         free(ait.lb);
 216                                 } else
 217                                         if (v_txt_auto(sp,
 218                                             OOBLNO, tp, tp->len, ntp))
 219                                                 goto err;
 220                                 carat_st = C_NOTSET;
 221                         }
 222                         txt_prompt(sp, ntp, prompt, flags);
 223
 224                         /*
 225                          * Swap old and new TEXT's, and insert the new TEXT
 226                          * into the queue.
 227                          */
 228                         tp = ntp;
 229                         TAILQ_INSERT_TAIL(tiqh, tp, q);
 230                         break;
 231                 case K_CARAT:                   /* Delete autoindent chars. */
 232                         if (tp->len <= tp->ai && LF_ISSET(TXT_AUTOINDENT))
 233                                 carat_st = C_CARATSET;
 234                         goto ins_ch;
 235                 case K_ZERO:                    /* Delete autoindent chars. */
 236                         if (tp->len <= tp->ai && LF_ISSET(TXT_AUTOINDENT))
 237                                 carat_st = C_ZEROSET;
 238                         goto ins_ch;
 239                 case K_CNTRLD:                  /* Delete autoindent char. */
 240                         /*
 241                          * !!!
 242                          * Historically, the ^D command took (but then ignored)
 243                          * a count.  For simplicity, we don't return it unless
 244                          * it's the first character entered.  The check for len
 245                          * equal to 0 is okay, TXT_AUTOINDENT won't be set.
 246                          */
 247                         if (LF_ISSET(TXT_CNTRLD)) {
 248                                 for (cnt = 0; cnt < tp->len; ++cnt)
 249                                         if (!isblank(tp->lb[cnt]))
 250                                                 break;
 251                                 if (cnt == tp->len) {
 252                                         tp->len = 1;
 253                                         tp->lb[0] = ev.e_c;
 254                                         tp->lb[1] = '\0';
 255
 256                                         /*
 257                                          * Put out a line separator, in case
 258                                          * the command fails.
 259                                          */
 260                                         (void)putchar('\n');
 261                                         goto done;
 262                                 }
 263                         }
 264
 265                         /*
 266                          * POSIX 1003.1b-1993, paragraph 7.1.1.9, states that
 267                          * the EOF characters are discarded if there are other
 268                          * characters to process in the line, i.e. if the EOF
 269                          * is not the first character in the line.  For this
 270                          * reason, historic ex discarded the EOF characters,
 271                          * even if occurring in the middle of the input line.
 272                          * We match that historic practice.
 273                          *
 274                          * !!!
 275                          * The test for discarding in the middle of the line is
 276                          * done in the switch, because the CARAT forms are N+1,
 277                          * not N.
 278                          *
 279                          * !!!
 280                          * There's considerable magic to make the terminal code
 281                          * return the EOF character at all.  See that code for
 282                          * details.
 283                          */
 284                         if (!LF_ISSET(TXT_AUTOINDENT) || tp->len == 0)
 285                                 continue;
 286                         switch (carat_st) {
 287                         case C_CARATSET:                /* ^^D */
 288                                 if (tp->len > tp->ai + 1)
 289                                         continue;
 290
 291                                 /* Save the ai string for later. */
 292                                 ait.lb = NULL;
 293                                 ait.lb_len = 0;
 294                                 BINC_GOTOW(sp, ait.lb, ait.lb_len, tp->ai);
 295                                 MEMCPY(ait.lb, tp->lb, tp->ai);
 296                                 ait.ai = ait.len = tp->ai;
 297
 298                                 carat_st = C_NOTSET;
 299                                 nochange = 1;
 300                                 goto leftmargin;
 301                         case C_ZEROSET:                 /* 0^D */
 302                                 if (tp->len > tp->ai + 1)
 303                                         continue;
 304
 305                                 carat_st = C_NOTSET;
 306 leftmargin:                     (void)gp->scr_ex_adjust(sp, EX_TERM_CE);
 307                                 tp->ai = tp->len = 0;
 308                                 break;
 309                         case C_NOTSET:                  /* ^D */
 310                                 if (tp->len > tp->ai)
 311                                         continue;
 312
 313                                 if (txt_dent(sp, tp))
 314                                         goto err;
 315                                 break;
 316                         default:
 317                                 abort();
 318                         }
 319
 320                         /* Clear and redisplay the line. */
 321                         (void)gp->scr_ex_adjust(sp, EX_TERM_CE);
 322                         txt_prompt(sp, tp, prompt, flags);
 323                         break;
 324                 default:
 325                         /*
 326                          * See the TXT_BEAUTIFY comment in vi/v_txt_ev.c.
 327                          *
 328                          * Silently eliminate any iscntrl() character that was
 329                          * not already handled specially, except for <tab> and
 330                          * <ff>.
 331                          */
 332 ins_ch:                 if (LF_ISSET(TXT_BEAUTIFY) && ISCNTRL(ev.e_c) &&
 333                             ev.e_value != K_FORMFEED && ev.e_value != K_TAB)
 334                                 break;
 335
 336                         tp->lb[tp->len++] = ev.e_c;
 337                         break;
 338                 }
 339         }
 340         /* NOTREACHED */
 341
 342 done:   return (rval);
 343
 344 err:
 345 alloc_err:
 346         return (1);
 347 }
 348
 349 /*
 350  * txt_prompt --
 351  *      Display the ex prompt, line number, ai characters.  Characters had
 352  *      better be printable by the terminal driver, but that's its problem,
 353  *      not ours.
 354  */
 355 static void
 356 txt_prompt(SCR *sp, TEXT *tp, ARG_CHAR_T prompt, u_int32_t flags)
 357 {
 358         /* Display the prompt. */
 359         if (LF_ISSET(TXT_PROMPT))
 360                 (void)ex_printf(sp, "%c", prompt);
 361
 362         /* Display the line number. */
 363         if (LF_ISSET(TXT_NUMBER) && O_ISSET(sp, O_NUMBER))
 364                 (void)ex_printf(sp, "%6lu  ", (u_long)tp->lno);
 365
 366         /* Print out autoindent string. */
 367         if (LF_ISSET(TXT_AUTOINDENT))
 368                 (void)ex_printf(sp, WVS, (int)tp->ai, tp->lb);
 369         (void)ex_fflush(sp);
 370 }
 371
 372 /*
 373  * txt_dent --
 374  *      Handle ^D outdents.
 375  *
 376  * Ex version of vi/v_ntext.c:txt_dent().  See that code for the (usual)
 377  * ranting and raving.  This is a fair bit simpler as ^T isn't special.
 378  */
 379 static int
 380 txt_dent(SCR *sp, TEXT *tp)
 381 {
 382         u_long sw, ts;
 383         size_t cno, off, scno, spaces, tabs;
 384
 385         ts = O_VAL(sp, O_TABSTOP);
 386         sw = O_VAL(sp, O_SHIFTWIDTH);
 387
 388         /* Get the current screen column. */
 389         for (off = scno = 0; off < tp->len; ++off)
 390                 if (tp->lb[off] == '\t')
 391                         scno += COL_OFF(scno, ts);
 392                 else
 393                         ++scno;
 394
 395         /* Get the previous shiftwidth column. */
 396         cno = scno--;
 397         scno -= scno % sw;
 398
 399         /*
 400          * Since we don't know what comes before the character(s) being
 401          * deleted, we have to resolve the autoindent characters .  The
 402          * example is a <tab>, which doesn't take up a full shiftwidth
 403          * number of columns because it's preceded by <space>s.  This is
 404          * easy to get if the user sets shiftwidth to a value less than
 405          * tabstop, and then uses ^T to indent, and ^D to outdent.
 406          *
 407          * Count up spaces/tabs needed to get to the target.
 408          */
 409         for (cno = 0, tabs = 0; cno + COL_OFF(cno, ts) <= scno; ++tabs)
 410                 cno += COL_OFF(cno, ts);
 411         spaces = scno - cno;
 412
 413         /* Make sure there's enough room. */
 414         BINC_RETW(sp, tp->lb, tp->lb_len, tabs + spaces + 1);
 415
 416         /* Adjust the final ai character count. */
 417         tp->ai = tabs + spaces;
 418
 419         /* Enter the replacement characters. */
 420         for (tp->len = 0; tabs > 0; --tabs)
 421                 tp->lb[tp->len++] = '\t';
 422         for (; spaces > 0; --spaces)
 423                 tp->lb[tp->len++] = ' ';
 424         return (0);
 425 }