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