lib/libedit/read.c

   1 /*      $NetBSD: read.c,v 1.53 2009/12/30 22:37:40 christos Exp $       */
   2
   3 /*-
   4  * Copyright (c) 1992, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * This code is derived from software contributed to Berkeley by
   8  * Christos Zoulas of Cornell University.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #include "config.h"
  36 #if !defined(lint) && !defined(SCCSID)
  37 #if 0
  38 static char sccsid[] = "@(#)read.c      8.1 (Berkeley) 6/4/93";
  39 #else
  40 __RCSID("$NetBSD: read.c,v 1.53 2009/12/30 22:37:40 christos Exp $");
  41 #endif
  42 #endif /* not lint && not SCCSID */
  43
  44 /*
  45  * read.c: Clean this junk up! This is horrible code.
  46  *         Terminal read functions
  47  */
  48 #include <errno.h>
  49 #include <fcntl.h>
  50 #include <unistd.h>
  51 #include <stdlib.h>
  52 #include <limits.h>
  53 #include "el.h"
  54
  55 #define OKCMD   -1      /* must be -1! */
  56
  57 private int     read__fixio(int, int);
  58 private int     read_preread(EditLine *);
  59 private int     read_char(EditLine *, Char *);
  60 private int     read_getcmd(EditLine *, el_action_t *, Char *);
  61 private void    read_pop(c_macro_t *);
  62
  63 /* read_init():
  64  *      Initialize the read stuff
  65  */
  66 protected int
  67 read_init(EditLine *el)
  68 {
  69         /* builtin read_char */
  70         el->el_read.read_char = read_char;
  71         return 0;
  72 }
  73
  74
  75 /* el_read_setfn():
  76  *      Set the read char function to the one provided.
  77  *      If it is set to EL_BUILTIN_GETCFN, then reset to the builtin one.
  78  */
  79 protected int
  80 el_read_setfn(EditLine *el, el_rfunc_t rc)
  81 {
  82         el->el_read.read_char = (rc == EL_BUILTIN_GETCFN) ? read_char : rc;
  83         return 0;
  84 }
  85
  86
  87 /* el_read_getfn():
  88  *      return the current read char function, or EL_BUILTIN_GETCFN
  89  *      if it is the default one
  90  */
  91 protected el_rfunc_t
  92 el_read_getfn(EditLine *el)
  93 {
  94        return (el->el_read.read_char == read_char) ?
  95             EL_BUILTIN_GETCFN : el->el_read.read_char;
  96 }
  97
  98
  99 #ifndef MIN
 100 #define MIN(A,B) ((A) < (B) ? (A) : (B))
 101 #endif
 102
 103 #ifdef DEBUG_EDIT
 104 private void
 105 read_debug(EditLine *el)
 106 {
 107
 108         if (el->el_line.cursor > el->el_line.lastchar)
 109                 (void) fprintf(el->el_errfile, "cursor > lastchar\r\n");
 110         if (el->el_line.cursor < el->el_line.buffer)
 111                 (void) fprintf(el->el_errfile, "cursor < buffer\r\n");
 112         if (el->el_line.cursor > el->el_line.limit)
 113                 (void) fprintf(el->el_errfile, "cursor > limit\r\n");
 114         if (el->el_line.lastchar > el->el_line.limit)
 115                 (void) fprintf(el->el_errfile, "lastchar > limit\r\n");
 116         if (el->el_line.limit != &el->el_line.buffer[EL_BUFSIZ - 2])
 117                 (void) fprintf(el->el_errfile, "limit != &buffer[EL_BUFSIZ-2]\r\n");
 118 }
 119 #endif /* DEBUG_EDIT */
 120
 121
 122 /* read__fixio():
 123  *      Try to recover from a read error
 124  */
 125 /* ARGSUSED */
 126 private int
 127 read__fixio(int fd __attribute__((__unused__)), int e)
 128 {
 129
 130         switch (e) {
 131         case -1:                /* Make sure that the code is reachable */
 132
 133 #ifdef EWOULDBLOCK
 134         case EWOULDBLOCK:
 135 #ifndef TRY_AGAIN
 136 #define TRY_AGAIN
 137 #endif
 138 #endif /* EWOULDBLOCK */
 139
 140 #if defined(POSIX) && defined(EAGAIN)
 141 #if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
 142         case EAGAIN:
 143 #ifndef TRY_AGAIN
 144 #define TRY_AGAIN
 145 #endif
 146 #endif /* EWOULDBLOCK && EWOULDBLOCK != EAGAIN */
 147 #endif /* POSIX && EAGAIN */
 148
 149                 e = 0;
 150 #ifdef TRY_AGAIN
 151 #if defined(F_SETFL) && defined(O_NDELAY)
 152                 if ((e = fcntl(fd, F_GETFL, 0)) == -1)
 153                         return (-1);
 154
 155                 if (fcntl(fd, F_SETFL, e & ~O_NDELAY) == -1)
 156                         return (-1);
 157                 else
 158                         e = 1;
 159 #endif /* F_SETFL && O_NDELAY */
 160
 161 #ifdef FIONBIO
 162                 {
 163                         int zero = 0;
 164
 165                         if (ioctl(fd, FIONBIO, (ioctl_t) & zero) == -1)
 166                                 return (-1);
 167                         else
 168                                 e = 1;
 169                 }
 170 #endif /* FIONBIO */
 171
 172 #endif /* TRY_AGAIN */
 173                 return (e ? 0 : -1);
 174
 175         case EINTR:
 176                 return (-1);
 177
 178         default:
 179                 return (-1);
 180         }
 181 }
 182
 183
 184 /* read_preread():
 185  *      Try to read the stuff in the input queue;
 186  */
 187 private int
 188 read_preread(EditLine *el)
 189 {
 190         int chrs = 0;
 191
 192         if (el->el_tty.t_mode == ED_IO)
 193                 return (0);
 194
 195 #ifndef WIDECHAR
 196 /* FIONREAD attempts to buffer up multiple bytes, and to make that work
 197  * properly with partial wide/UTF-8 characters would need some careful work. */
 198 #ifdef FIONREAD
 199         (void) ioctl(el->el_infd, FIONREAD, (ioctl_t) & chrs);
 200         if (chrs > 0) {
 201                 char buf[EL_BUFSIZ];
 202
 203                 chrs = read(el->el_infd, buf,
 204                     (size_t) MIN(chrs, EL_BUFSIZ - 1));
 205                 if (chrs > 0) {
 206                         buf[chrs] = '\0';
 207                         el_push(el, buf);
 208                 }
 209         }
 210 #endif /* FIONREAD */
 211 #endif
 212         return (chrs > 0);
 213 }
 214
 215
 216 /* el_push():
 217  *      Push a macro
 218  */
 219 public void
 220 FUN(el,push)(EditLine *el, const Char *str)
 221 {
 222         c_macro_t *ma = &el->el_chared.c_macro;
 223
 224         if (str != NULL && ma->level + 1 < EL_MAXMACRO) {
 225                 ma->level++;
 226                 if ((ma->macro[ma->level] = Strdup(str)) != NULL)
 227                         return;
 228                 ma->level--;
 229         }
 230         term_beep(el);
 231         term__flush(el);
 232 }
 233
 234
 235 /* read_getcmd():
 236  *      Return next command from the input stream.
 237  *      Character values > 255 are not looked up in the map, but inserted.
 238  */
 239 private int
 240 read_getcmd(EditLine *el, el_action_t *cmdnum, Char *ch)
 241 {
 242         el_action_t cmd;
 243         int num;
 244
 245         el->el_errno = 0;
 246         do {
 247                 if ((num = FUN(el,getc)(el, ch)) != 1) {/* if EOF or error */
 248                         el->el_errno = num == 0 ? 0 : errno;
 249                         return (num);
 250                 }
 251
 252 #ifdef  KANJI
 253                 if ((*ch & 0200)) {
 254                         el->el_state.metanext = 0;
 255                         cmd = CcViMap[' '];
 256                         break;
 257                 } else
 258 #endif /* KANJI */
 259
 260                 if (el->el_state.metanext) {
 261                         el->el_state.metanext = 0;
 262                         *ch |= 0200;
 263                 }
 264 #ifdef WIDECHAR
 265                 if (*ch >= N_KEYS)
 266                         cmd = ED_INSERT;
 267                 else
 268 #endif
 269                         cmd = el->el_map.current[(unsigned char) *ch];
 270                 if (cmd == ED_SEQUENCE_LEAD_IN) {
 271                         key_value_t val;
 272                         switch (key_get(el, ch, &val)) {
 273                         case XK_CMD:
 274                                 cmd = val.cmd;
 275                                 break;
 276                         case XK_STR:
 277                                 FUN(el,push)(el, val.str);
 278                                 break;
 279 #ifdef notyet
 280                         case XK_EXE:
 281                                 /* XXX: In the future to run a user function */
 282                                 RunCommand(val.str);
 283                                 break;
 284 #endif
 285                         default:
 286                                 EL_ABORT((el->el_errfile, "Bad XK_ type \n"));
 287                                 break;
 288                         }
 289                 }
 290                 if (el->el_map.alt == NULL)
 291                         el->el_map.current = el->el_map.key;
 292         } while (cmd == ED_SEQUENCE_LEAD_IN);
 293         *cmdnum = cmd;
 294         return (OKCMD);
 295 }
 296
 297 #ifdef WIDECHAR
 298 /* utf8_islead():
 299  *      Test whether a byte is a leading byte of a UTF-8 sequence.
 300  */
 301 private int
 302 utf8_islead(unsigned char c)
 303 {
 304         return (c < 0x80) ||             /* single byte char */
 305                (c >= 0xc2 && c <= 0xf4); /* start of multibyte sequence */
 306 }
 307 #endif
 308
 309 /* read_char():
 310  *      Read a character from the tty.
 311  */
 312 private int
 313 read_char(EditLine *el, Char *cp)
 314 {
 315         ssize_t num_read;
 316         int tried = 0;
 317         char cbuf[MB_LEN_MAX];
 318         int cbp = 0;
 319         int bytes = 0;
 320
 321  again:
 322         el->el_signal->sig_no = 0;
 323         while ((num_read = read(el->el_infd, cbuf + cbp, 1)) == -1) {
 324                 if (el->el_signal->sig_no == SIGCONT) {
 325                         sig_set(el);
 326                         el_set(el, EL_REFRESH);
 327                         goto again;
 328                 }
 329                 if (!tried && read__fixio(el->el_infd, errno) == 0)
 330                         tried = 1;
 331                 else {
 332                         *cp = '\0';
 333                         return (-1);
 334                 }
 335         }
 336
 337 #ifdef WIDECHAR
 338         if (el->el_flags & CHARSET_IS_UTF8) {
 339                 if (!utf8_islead((unsigned char)cbuf[0]))
 340                         goto again; /* discard the byte we read and try again */
 341                 ++cbp;
 342                 if ((bytes = ct_mbtowc(cp, cbuf, cbp)) == -1) {
 343                         ct_mbtowc_reset;
 344                         if (cbp >= MB_LEN_MAX) { /* "shouldn't happen" */
 345                                 *cp = '\0';
 346                                 return (-1);
 347                         }
 348                         goto again;
 349                 }
 350         } else  /* we don't support other multibyte charsets */
 351 #endif
 352                 *cp = (unsigned char)cbuf[0];
 353
 354         if ((el->el_flags & IGNORE_EXTCHARS) && bytes > 1) {
 355                 cbp = 0; /* skip this character */
 356                 goto again;
 357         }
 358
 359         return (int)num_read;
 360 }
 361
 362 /* read_pop():
 363  *      Pop a macro from the stack
 364  */
 365 private void
 366 read_pop(c_macro_t *ma)
 367 {
 368         int i;
 369
 370         el_free(ma->macro[0]);
 371         for (i = 0; i < ma->level; i++)
 372                 ma->macro[i] = ma->macro[i + 1];
 373         ma->level--;
 374         ma->offset = 0;
 375 }
 376
 377 /* el_getc():
 378  *      Read a character
 379  */
 380 public int
 381 FUN(el,getc)(EditLine *el, Char *cp)
 382 {
 383         int num_read;
 384         c_macro_t *ma = &el->el_chared.c_macro;
 385
 386         term__flush(el);
 387         for (;;) {
 388                 if (ma->level < 0) {
 389                         if (!read_preread(el))
 390                                 break;
 391                 }
 392
 393                 if (ma->level < 0)
 394                         break;
 395
 396                 if (ma->macro[0][ma->offset] == '\0') {
 397                         read_pop(ma);
 398                         continue;
 399                 }
 400
 401                 *cp = ma->macro[0][ma->offset++];
 402
 403                 if (ma->macro[0][ma->offset] == '\0') {
 404                         /* Needed for QuoteMode On */
 405                         read_pop(ma);
 406                 }
 407
 408                 return (1);
 409         }
 410
 411 #ifdef DEBUG_READ
 412         (void) fprintf(el->el_errfile, "Turning raw mode on\n");
 413 #endif /* DEBUG_READ */
 414         if (tty_rawmode(el) < 0)/* make sure the tty is set up correctly */
 415                 return (0);
 416
 417 #ifdef DEBUG_READ
 418         (void) fprintf(el->el_errfile, "Reading a character\n");
 419 #endif /* DEBUG_READ */
 420         num_read = (*el->el_read.read_char)(el, cp);
 421 #ifdef WIDECHAR
 422         if (el->el_flags & NARROW_READ)
 423                 *cp = *(char *)(void *)cp;
 424 #endif
 425 #ifdef DEBUG_READ
 426         (void) fprintf(el->el_errfile, "Got it %c\n", *cp);
 427 #endif /* DEBUG_READ */
 428         return (num_read);
 429 }
 430
 431 protected void
 432 read_prepare(EditLine *el)
 433 {
 434         if (el->el_flags & HANDLE_SIGNALS)
 435                 sig_set(el);
 436         if (el->el_flags & NO_TTY)
 437                 return;
 438         if ((el->el_flags & (UNBUFFERED|EDIT_DISABLED)) == UNBUFFERED)
 439                 tty_rawmode(el);
 440
 441         /* This is relatively cheap, and things go terribly wrong if
 442            we have the wrong size. */
 443         el_resize(el);
 444         re_clear_display(el);   /* reset the display stuff */
 445         ch_reset(el, 0);
 446         re_refresh(el);         /* print the prompt */
 447
 448         if (el->el_flags & UNBUFFERED)
 449                 term__flush(el);
 450 }
 451
 452 protected void
 453 read_finish(EditLine *el)
 454 {
 455         if ((el->el_flags & UNBUFFERED) == 0)
 456                 (void) tty_cookedmode(el);
 457         if (el->el_flags & HANDLE_SIGNALS)
 458                 sig_clr(el);
 459 }
 460
 461 public const Char *
 462 FUN(el,gets)(EditLine *el, int *nread)
 463 {
 464         int retval;
 465         el_action_t cmdnum = 0;
 466         int num;                /* how many chars we have read at NL */
 467         Char ch;
 468         int crlf = 0;
 469         int nrb;
 470 #ifdef FIONREAD
 471         c_macro_t *ma = &el->el_chared.c_macro;
 472 #endif /* FIONREAD */
 473
 474         if (nread == NULL)
 475                 nread = &nrb;
 476         *nread = 0;
 477
 478         if (el->el_flags & NO_TTY) {
 479                 Char *cp = el->el_line.buffer;
 480                 size_t idx;
 481
 482                 while ((num = (*el->el_read.read_char)(el, cp)) == 1) {
 483                         /* make sure there is space for next character */
 484                         if (cp + 1 >= el->el_line.limit) {
 485                                 idx = (cp - el->el_line.buffer);
 486                                 if (!ch_enlargebufs(el, 2))
 487                                         break;
 488                                 cp = &el->el_line.buffer[idx];
 489                         }
 490                         cp++;
 491                         if (el->el_flags & UNBUFFERED)
 492                                 break;
 493                         if (cp[-1] == '\r' || cp[-1] == '\n')
 494                                 break;
 495                 }
 496                 if (num == -1) {
 497                         if (errno == EINTR)
 498                                 cp = el->el_line.buffer;
 499                         el->el_errno = errno;
 500                 }
 501
 502                 el->el_line.cursor = el->el_line.lastchar = cp;
 503                 *cp = '\0';
 504                 *nread = (int)(el->el_line.cursor - el->el_line.buffer);
 505                 goto done;
 506         }
 507
 508
 509 #ifdef FIONREAD
 510         if (el->el_tty.t_mode == EX_IO && ma->level < 0) {
 511                 long chrs = 0;
 512
 513                 (void) ioctl(el->el_infd, FIONREAD, (ioctl_t) & chrs);
 514                 if (chrs == 0) {
 515                         if (tty_rawmode(el) < 0) {
 516                                 errno = 0;
 517                                 *nread = 0;
 518                                 return (NULL);
 519                         }
 520                 }
 521         }
 522 #endif /* FIONREAD */
 523
 524         if ((el->el_flags & UNBUFFERED) == 0)
 525                 read_prepare(el);
 526
 527         if (el->el_flags & EDIT_DISABLED) {
 528                 Char *cp;
 529                 size_t idx;
 530
 531                 if ((el->el_flags & UNBUFFERED) == 0)
 532                         cp = el->el_line.buffer;
 533                 else
 534                         cp = el->el_line.lastchar;
 535
 536                 term__flush(el);
 537
 538                 while ((num = (*el->el_read.read_char)(el, cp)) == 1) {
 539                         /* make sure there is space next character */
 540                         if (cp + 1 >= el->el_line.limit) {
 541                                 idx = (cp - el->el_line.buffer);
 542                                 if (!ch_enlargebufs(el, 2))
 543                                         break;
 544                                 cp = &el->el_line.buffer[idx];
 545                         }
 546                         cp++;
 547                         crlf = cp[-1] == '\r' || cp[-1] == '\n';
 548                         if (el->el_flags & UNBUFFERED)
 549                                 break;
 550                         if (crlf)
 551                                 break;
 552                 }
 553
 554                 if (num == -1) {
 555                         if (errno == EINTR)
 556                                 cp = el->el_line.buffer;
 557                         el->el_errno = errno;
 558                 }
 559
 560                 el->el_line.cursor = el->el_line.lastchar = cp;
 561                 *cp = '\0';
 562                 goto done;
 563         }
 564
 565         for (num = OKCMD; num == OKCMD;) {      /* while still editing this
 566                                                  * line */
 567 #ifdef DEBUG_EDIT
 568                 read_debug(el);
 569 #endif /* DEBUG_EDIT */
 570                 /* if EOF or error */
 571                 if ((num = read_getcmd(el, &cmdnum, &ch)) != OKCMD) {
 572 #ifdef DEBUG_READ
 573                         (void) fprintf(el->el_errfile,
 574                             "Returning from el_gets %d\n", num);
 575 #endif /* DEBUG_READ */
 576                         break;
 577                 }
 578                 if (el->el_errno == EINTR) {
 579                         el->el_line.buffer[0] = '\0';
 580                         el->el_line.lastchar =
 581                             el->el_line.cursor = el->el_line.buffer;
 582                         break;
 583                 }
 584                 if ((unsigned int)cmdnum >= (unsigned int)el->el_map.nfunc) {   /* BUG CHECK command */
 585 #ifdef DEBUG_EDIT
 586                         (void) fprintf(el->el_errfile,
 587                             "ERROR: illegal command from key 0%o\r\n", ch);
 588 #endif /* DEBUG_EDIT */
 589                         continue;       /* try again */
 590                 }
 591                 /* now do the real command */
 592 #ifdef DEBUG_READ
 593                 {
 594                         el_bindings_t *b;
 595                         for (b = el->el_map.help; b->name; b++)
 596                                 if (b->func == cmdnum)
 597                                         break;
 598                         if (b->name)
 599                                 (void) fprintf(el->el_errfile,
 600                                     "Executing %s\n", b->name);
 601                         else
 602                                 (void) fprintf(el->el_errfile,
 603                                     "Error command = %d\n", cmdnum);
 604                 }
 605 #endif /* DEBUG_READ */
 606                 /* vi redo needs these way down the levels... */
 607                 el->el_state.thiscmd = cmdnum;
 608                 el->el_state.thisch = ch;
 609                 if (el->el_map.type == MAP_VI &&
 610                     el->el_map.current == el->el_map.key &&
 611                     el->el_chared.c_redo.pos < el->el_chared.c_redo.lim) {
 612                         if (cmdnum == VI_DELETE_PREV_CHAR &&
 613                             el->el_chared.c_redo.pos != el->el_chared.c_redo.buf
 614                             && Isprint(el->el_chared.c_redo.pos[-1]))
 615                                 el->el_chared.c_redo.pos--;
 616                         else
 617                                 *el->el_chared.c_redo.pos++ = ch;
 618                 }
 619                 retval = (*el->el_map.func[cmdnum]) (el, ch);
 620 #ifdef DEBUG_READ
 621                 (void) fprintf(el->el_errfile,
 622                         "Returned state %d\n", retval );
 623 #endif /* DEBUG_READ */
 624
 625                 /* save the last command here */
 626                 el->el_state.lastcmd = cmdnum;
 627
 628                 /* use any return value */
 629                 switch (retval) {
 630                 case CC_CURSOR:
 631                         re_refresh_cursor(el);
 632                         break;
 633
 634                 case CC_REDISPLAY:
 635                         re_clear_lines(el);
 636                         re_clear_display(el);
 637                         /* FALLTHROUGH */
 638
 639                 case CC_REFRESH:
 640                         re_refresh(el);
 641                         break;
 642
 643                 case CC_REFRESH_BEEP:
 644                         re_refresh(el);
 645                         term_beep(el);
 646                         break;
 647
 648                 case CC_NORM:   /* normal char */
 649                         break;
 650
 651                 case CC_ARGHACK:        /* Suggested by Rich Salz */
 652                         /* <rsalz@pineapple.bbn.com> */
 653                         continue;       /* keep going... */
 654
 655                 case CC_EOF:    /* end of file typed */
 656                         if ((el->el_flags & UNBUFFERED) == 0)
 657                                 num = 0;
 658                         else if (num == -1) {
 659                                 *el->el_line.lastchar++ = CONTROL('d');
 660                                 el->el_line.cursor = el->el_line.lastchar;
 661                                 num = 1;
 662                         }
 663                         break;
 664
 665                 case CC_NEWLINE:        /* normal end of line */
 666                         num = (int)(el->el_line.lastchar - el->el_line.buffer);
 667                         break;
 668
 669                 case CC_FATAL:  /* fatal error, reset to known state */
 670 #ifdef DEBUG_READ
 671                         (void) fprintf(el->el_errfile,
 672                             "*** editor fatal ERROR ***\r\n\n");
 673 #endif /* DEBUG_READ */
 674                         /* put (real) cursor in a known place */
 675                         re_clear_display(el);   /* reset the display stuff */
 676                         ch_reset(el, 1);        /* reset the input pointers */
 677                         re_refresh(el); /* print the prompt again */
 678                         break;
 679
 680                 case CC_ERROR:
 681                 default:        /* functions we don't know about */
 682 #ifdef DEBUG_READ
 683                         (void) fprintf(el->el_errfile,
 684                             "*** editor ERROR ***\r\n\n");
 685 #endif /* DEBUG_READ */
 686                         term_beep(el);
 687                         term__flush(el);
 688                         break;
 689                 }
 690                 el->el_state.argument = 1;
 691                 el->el_state.doingarg = 0;
 692                 el->el_chared.c_vcmd.action = NOP;
 693                 if (el->el_flags & UNBUFFERED)
 694                         break;
 695         }
 696
 697         term__flush(el);                /* flush any buffered output */
 698         /* make sure the tty is set up correctly */
 699         if ((el->el_flags & UNBUFFERED) == 0) {
 700                 read_finish(el);
 701                 *nread = num != -1 ? num : 0;
 702         } else {
 703                 *nread = (int)(el->el_line.lastchar - el->el_line.buffer);
 704         }
 705 done:
 706         if (*nread == 0) {
 707                 if (num == -1) {
 708                         *nread = -1;
 709                         errno = el->el_errno;
 710                 }
 711                 return NULL;
 712         } else
 713                 return el->el_line.buffer;
 714 }