src/read.c

   1 /*      $NetBSD: read.c,v 1.52 2009/07/22 15:57:00 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 1.52 2009/07/22 15:57:00 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 "el.h"
  53
  54 #define OKCMD   -1      /* must be -1! */
  55
  56 private int     read__fixio(int, int);
  57 private int     read_preread(EditLine *);
  58 private int     read_char(EditLine *, char *);
  59 private int     read_getcmd(EditLine *, el_action_t *, char *);
  60 private void    read_pop(c_macro_t *);
  61
  62 /* read_init():
  63  *      Initialize the read stuff
  64  */
  65 protected int
  66 read_init(EditLine *el)
  67 {
  68         /* builtin read_char */
  69         el->el_read.read_char = read_char;
  70         return 0;
  71 }
  72
  73
  74 /* el_read_setfn():
  75  *      Set the read char function to the one provided.
  76  *      If it is set to EL_BUILTIN_GETCFN, then reset to the builtin one.
  77  */
  78 protected int
  79 el_read_setfn(EditLine *el, el_rfunc_t rc)
  80 {
  81         el->el_read.read_char = (rc == EL_BUILTIN_GETCFN) ? read_char : rc;
  82         return 0;
  83 }
  84
  85
  86 /* el_read_getfn():
  87  *      return the current read char function, or EL_BUILTIN_GETCFN
  88  *      if it is the default one
  89  */
  90 protected el_rfunc_t
  91 el_read_getfn(EditLine *el)
  92 {
  93        return (el->el_read.read_char == read_char) ?
  94             EL_BUILTIN_GETCFN : el->el_read.read_char;
  95 }
  96
  97
  98 #ifndef MIN
  99 #define MIN(A,B) ((A) < (B) ? (A) : (B))
 100 #endif
 101
 102 #ifdef DEBUG_EDIT
 103 private void
 104 read_debug(EditLine *el)
 105 {
 106
 107         if (el->el_line.cursor > el->el_line.lastchar)
 108                 (void) fprintf(el->el_errfile, "cursor > lastchar\r\n");
 109         if (el->el_line.cursor < el->el_line.buffer)
 110                 (void) fprintf(el->el_errfile, "cursor < buffer\r\n");
 111         if (el->el_line.cursor > el->el_line.limit)
 112                 (void) fprintf(el->el_errfile, "cursor > limit\r\n");
 113         if (el->el_line.lastchar > el->el_line.limit)
 114                 (void) fprintf(el->el_errfile, "lastchar > limit\r\n");
 115         if (el->el_line.limit != &el->el_line.buffer[EL_BUFSIZ - 2])
 116                 (void) fprintf(el->el_errfile, "limit != &buffer[EL_BUFSIZ-2]\r\n");
 117 }
 118 #endif /* DEBUG_EDIT */
 119
 120
 121 /* read__fixio():
 122  *      Try to recover from a read error
 123  */
 124 /* ARGSUSED */
 125 private int
 126 read__fixio(int fd __attribute__((__unused__)), int e)
 127 {
 128
 129         switch (e) {
 130         case -1:                /* Make sure that the code is reachable */
 131
 132 #ifdef EWOULDBLOCK
 133         case EWOULDBLOCK:
 134 #ifndef TRY_AGAIN
 135 #define TRY_AGAIN
 136 #endif
 137 #endif /* EWOULDBLOCK */
 138
 139 #if defined(POSIX) && defined(EAGAIN)
 140 #if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
 141         case EAGAIN:
 142 #ifndef TRY_AGAIN
 143 #define TRY_AGAIN
 144 #endif
 145 #endif /* EWOULDBLOCK && EWOULDBLOCK != EAGAIN */
 146 #endif /* POSIX && EAGAIN */
 147
 148                 e = 0;
 149 #ifdef TRY_AGAIN
 150 #if defined(F_SETFL) && defined(O_NDELAY)
 151                 if ((e = fcntl(fd, F_GETFL, 0)) == -1)
 152                         return (-1);
 153
 154                 if (fcntl(fd, F_SETFL, e & ~O_NDELAY) == -1)
 155                         return (-1);
 156                 else
 157                         e = 1;
 158 #endif /* F_SETFL && O_NDELAY */
 159
 160 #ifdef FIONBIO
 161                 {
 162                         int zero = 0;
 163
 164                         if (ioctl(fd, FIONBIO, (ioctl_t) & zero) == -1)
 165                                 return (-1);
 166                         else
 167                                 e = 1;
 168                 }
 169 #endif /* FIONBIO */
 170
 171 #endif /* TRY_AGAIN */
 172                 return (e ? 0 : -1);
 173
 174         case EINTR:
 175                 return (-1);
 176
 177         default:
 178                 return (-1);
 179         }
 180 }
 181
 182
 183 /* read_preread():
 184  *      Try to read the stuff in the input queue;
 185  */
 186 private int
 187 read_preread(EditLine *el)
 188 {
 189         int chrs = 0;
 190
 191         if (el->el_tty.t_mode == ED_IO)
 192                 return (0);
 193
 194 #ifdef FIONREAD
 195         (void) ioctl(el->el_infd, FIONREAD, (ioctl_t) & chrs);
 196         if (chrs > 0) {
 197                 char buf[EL_BUFSIZ];
 198
 199                 chrs = read(el->el_infd, buf,
 200                     (size_t) MIN(chrs, EL_BUFSIZ - 1));
 201                 if (chrs > 0) {
 202                         buf[chrs] = '\0';
 203                         el_push(el, buf);
 204                 }
 205         }
 206 #endif /* FIONREAD */
 207
 208         return (chrs > 0);
 209 }
 210
 211
 212 /* el_push():
 213  *      Push a macro
 214  */
 215 public void
 216 el_push(EditLine *el, const char *str)
 217 {
 218         c_macro_t *ma = &el->el_chared.c_macro;
 219
 220         if (str != NULL && ma->level + 1 < EL_MAXMACRO) {
 221                 ma->level++;
 222                 if ((ma->macro[ma->level] = el_strdup(str)) != NULL)
 223                         return;
 224                 ma->level--;
 225         }
 226         term_beep(el);
 227         term__flush(el);
 228 }
 229
 230
 231 /* read_getcmd():
 232  *      Return next command from the input stream.
 233  */
 234 private int
 235 read_getcmd(EditLine *el, el_action_t *cmdnum, char *ch)
 236 {
 237         el_action_t cmd;
 238         int num;
 239
 240         el->el_errno = 0;
 241         do {
 242                 if ((num = el_getc(el, ch)) != 1) {     /* if EOF or error */
 243                         el->el_errno = num == 0 ? 0 : errno;
 244                         return (num);
 245                 }
 246
 247 #ifdef  KANJI
 248                 if ((*ch & 0200)) {
 249                         el->el_state.metanext = 0;
 250                         cmd = CcViMap[' '];
 251                         break;
 252                 } else
 253 #endif /* KANJI */
 254
 255                 if (el->el_state.metanext) {
 256                         el->el_state.metanext = 0;
 257                         *ch |= 0200;
 258                 }
 259                 cmd = el->el_map.current[(unsigned char) *ch];
 260                 if (cmd == ED_SEQUENCE_LEAD_IN) {
 261                         key_value_t val;
 262                         switch (key_get(el, ch, &val)) {
 263                         case XK_CMD:
 264                                 cmd = val.cmd;
 265                                 break;
 266                         case XK_STR:
 267                                 el_push(el, val.str);
 268                                 break;
 269 #ifdef notyet
 270                         case XK_EXE:
 271                                 /* XXX: In the future to run a user function */
 272                                 RunCommand(val.str);
 273                                 break;
 274 #endif
 275                         default:
 276                                 EL_ABORT((el->el_errfile, "Bad XK_ type \n"));
 277                                 break;
 278                         }
 279                 }
 280                 if (el->el_map.alt == NULL)
 281                         el->el_map.current = el->el_map.key;
 282         } while (cmd == ED_SEQUENCE_LEAD_IN);
 283         *cmdnum = cmd;
 284         return (OKCMD);
 285 }
 286
 287
 288 /* read_char():
 289  *      Read a character from the tty.
 290  */
 291 private int
 292 read_char(EditLine *el, char *cp)
 293 {
 294         ssize_t num_read;
 295         int tried = 0;
 296
 297  again:
 298         el->el_signal->sig_no = 0;
 299         while ((num_read = read(el->el_infd, cp, 1)) == -1) {
 300                 if (el->el_signal->sig_no == SIGCONT) {
 301                         sig_set(el);
 302                         el_set(el, EL_REFRESH);
 303                         goto again;
 304                 }
 305                 if (!tried && read__fixio(el->el_infd, errno) == 0)
 306                         tried = 1;
 307                 else {
 308                         *cp = '\0';
 309                         return (-1);
 310                 }
 311         }
 312         return (int)num_read;
 313 }
 314
 315 /* read_pop():
 316  *      Pop a macro from the stack
 317  */
 318 private void
 319 read_pop(c_macro_t *ma)
 320 {
 321         int i;
 322
 323         el_free(ma->macro[0]);
 324         for (i = 0; i < ma->level; i++)
 325                 ma->macro[i] = ma->macro[i + 1];
 326         ma->level--;
 327         ma->offset = 0;
 328 }
 329
 330 /* el_getc():
 331  *      Read a character
 332  */
 333 public int
 334 el_getc(EditLine *el, char *cp)
 335 {
 336         int num_read;
 337         c_macro_t *ma = &el->el_chared.c_macro;
 338
 339         term__flush(el);
 340         for (;;) {
 341                 if (ma->level < 0) {
 342                         if (!read_preread(el))
 343                                 break;
 344                 }
 345
 346                 if (ma->level < 0)
 347                         break;
 348
 349                 if (ma->macro[0][ma->offset] == '\0') {
 350                         read_pop(ma);
 351                         continue;
 352                 }
 353
 354                 *cp = ma->macro[0][ma->offset++] & 0377;
 355
 356                 if (ma->macro[0][ma->offset] == '\0') {
 357                         /* Needed for QuoteMode On */
 358                         read_pop(ma);
 359                 }
 360
 361                 return (1);
 362         }
 363
 364 #ifdef DEBUG_READ
 365         (void) fprintf(el->el_errfile, "Turning raw mode on\n");
 366 #endif /* DEBUG_READ */
 367         if (tty_rawmode(el) < 0)/* make sure the tty is set up correctly */
 368                 return (0);
 369
 370 #ifdef DEBUG_READ
 371         (void) fprintf(el->el_errfile, "Reading a character\n");
 372 #endif /* DEBUG_READ */
 373         num_read = (*el->el_read.read_char)(el, cp);
 374 #ifdef DEBUG_READ
 375         (void) fprintf(el->el_errfile, "Got it %c\n", *cp);
 376 #endif /* DEBUG_READ */
 377         return (num_read);
 378 }
 379
 380 protected void
 381 read_prepare(EditLine *el)
 382 {
 383         if (el->el_flags & HANDLE_SIGNALS)
 384                 sig_set(el);
 385         if (el->el_flags & NO_TTY)
 386                 return;
 387         if ((el->el_flags & (UNBUFFERED|EDIT_DISABLED)) == UNBUFFERED)
 388                 tty_rawmode(el);
 389
 390         /* This is relatively cheap, and things go terribly wrong if
 391            we have the wrong size. */
 392         el_resize(el);
 393         re_clear_display(el);   /* reset the display stuff */
 394         ch_reset(el, 0);
 395         re_refresh(el);         /* print the prompt */
 396
 397         if (el->el_flags & UNBUFFERED)
 398                 term__flush(el);
 399 }
 400
 401 protected void
 402 read_finish(EditLine *el)
 403 {
 404         if ((el->el_flags & UNBUFFERED) == 0)
 405                 (void) tty_cookedmode(el);
 406         if (el->el_flags & HANDLE_SIGNALS)
 407                 sig_clr(el);
 408 }
 409
 410 public const char *
 411 el_gets(EditLine *el, int *nread)
 412 {
 413         int retval;
 414         el_action_t cmdnum = 0;
 415         int num;                /* how many chars we have read at NL */
 416         char ch;
 417         int crlf = 0;
 418         int nrb;
 419 #ifdef FIONREAD
 420         c_macro_t *ma = &el->el_chared.c_macro;
 421 #endif /* FIONREAD */
 422
 423         if (nread == NULL)
 424                 nread = &nrb;
 425         *nread = 0;
 426
 427         if (el->el_flags & NO_TTY) {
 428                 char *cp = el->el_line.buffer;
 429                 size_t idx;
 430
 431                 while ((num = (*el->el_read.read_char)(el, cp)) == 1) {
 432                         /* make sure there is space for next character */
 433                         if (cp + 1 >= el->el_line.limit) {
 434                                 idx = (cp - el->el_line.buffer);
 435                                 if (!ch_enlargebufs(el, 2))
 436                                         break;
 437                                 cp = &el->el_line.buffer[idx];
 438                         }
 439                         cp++;
 440                         if (el->el_flags & UNBUFFERED)
 441                                 break;
 442                         if (cp[-1] == '\r' || cp[-1] == '\n')
 443                                 break;
 444                 }
 445                 if (num == -1) {
 446                         if (errno == EINTR)
 447                                 cp = el->el_line.buffer;
 448                         el->el_errno = errno;
 449                 }
 450
 451                 el->el_line.cursor = el->el_line.lastchar = cp;
 452                 *cp = '\0';
 453                 *nread = (int)(el->el_line.cursor - el->el_line.buffer);
 454                 goto done;
 455         }
 456
 457
 458 #ifdef FIONREAD
 459         if (el->el_tty.t_mode == EX_IO && ma->level < 0) {
 460                 long chrs = 0;
 461
 462                 (void) ioctl(el->el_infd, FIONREAD, (ioctl_t) & chrs);
 463                 if (chrs == 0) {
 464                         if (tty_rawmode(el) < 0) {
 465                                 errno = 0;
 466                                 *nread = 0;
 467                                 return (NULL);
 468                         }
 469                 }
 470         }
 471 #endif /* FIONREAD */
 472
 473         if ((el->el_flags & UNBUFFERED) == 0)
 474                 read_prepare(el);
 475
 476         if (el->el_flags & EDIT_DISABLED) {
 477                 char *cp;
 478                 size_t idx;
 479
 480                 if ((el->el_flags & UNBUFFERED) == 0)
 481                         cp = el->el_line.buffer;
 482                 else
 483                         cp = el->el_line.lastchar;
 484
 485                 term__flush(el);
 486
 487                 while ((num = (*el->el_read.read_char)(el, cp)) == 1) {
 488                         /* make sure there is space next character */
 489                         if (cp + 1 >= el->el_line.limit) {
 490                                 idx = (cp - el->el_line.buffer);
 491                                 if (!ch_enlargebufs(el, 2))
 492                                         break;
 493                                 cp = &el->el_line.buffer[idx];
 494                         }
 495                         cp++;
 496                         crlf = cp[-1] == '\r' || cp[-1] == '\n';
 497                         if (el->el_flags & UNBUFFERED)
 498                                 break;
 499                         if (crlf)
 500                                 break;
 501                 }
 502
 503                 if (num == -1) {
 504                         if (errno == EINTR)
 505                                 cp = el->el_line.buffer;
 506                         el->el_errno = errno;
 507                 }
 508
 509                 el->el_line.cursor = el->el_line.lastchar = cp;
 510                 *cp = '\0';
 511                 goto done;
 512         }
 513
 514         for (num = OKCMD; num == OKCMD;) {      /* while still editing this
 515                                                  * line */
 516 #ifdef DEBUG_EDIT
 517                 read_debug(el);
 518 #endif /* DEBUG_EDIT */
 519                 /* if EOF or error */
 520                 if ((num = read_getcmd(el, &cmdnum, &ch)) != OKCMD) {
 521 #ifdef DEBUG_READ
 522                         (void) fprintf(el->el_errfile,
 523                             "Returning from el_gets %d\n", num);
 524 #endif /* DEBUG_READ */
 525                         break;
 526                 }
 527                 if (el->el_errno == EINTR) {
 528                         el->el_line.buffer[0] = '\0';
 529                         el->el_line.lastchar =
 530                             el->el_line.cursor = el->el_line.buffer;
 531                         break;
 532                 }
 533                 if ((unsigned int)cmdnum >= (unsigned int)el->el_map.nfunc) {   /* BUG CHECK command */
 534 #ifdef DEBUG_EDIT
 535                         (void) fprintf(el->el_errfile,
 536                             "ERROR: illegal command from key 0%o\r\n", ch);
 537 #endif /* DEBUG_EDIT */
 538                         continue;       /* try again */
 539                 }
 540                 /* now do the real command */
 541 #ifdef DEBUG_READ
 542                 {
 543                         el_bindings_t *b;
 544                         for (b = el->el_map.help; b->name; b++)
 545                                 if (b->func == cmdnum)
 546                                         break;
 547                         if (b->name)
 548                                 (void) fprintf(el->el_errfile,
 549                                     "Executing %s\n", b->name);
 550                         else
 551                                 (void) fprintf(el->el_errfile,
 552                                     "Error command = %d\n", cmdnum);
 553                 }
 554 #endif /* DEBUG_READ */
 555                 /* vi redo needs these way down the levels... */
 556                 el->el_state.thiscmd = cmdnum;
 557                 el->el_state.thisch = ch;
 558                 if (el->el_map.type == MAP_VI &&
 559                     el->el_map.current == el->el_map.key &&
 560                     el->el_chared.c_redo.pos < el->el_chared.c_redo.lim) {
 561                         if (cmdnum == VI_DELETE_PREV_CHAR &&
 562                             el->el_chared.c_redo.pos != el->el_chared.c_redo.buf
 563                             && isprint((unsigned char)el->el_chared.c_redo.pos[-1]))
 564                                 el->el_chared.c_redo.pos--;
 565                         else
 566                                 *el->el_chared.c_redo.pos++ = ch;
 567                 }
 568                 retval = (*el->el_map.func[cmdnum]) (el, ch);
 569 #ifdef DEBUG_READ
 570                 (void) fprintf(el->el_errfile,
 571                         "Returned state %d\n", retval );
 572 #endif /* DEBUG_READ */
 573
 574                 /* save the last command here */
 575                 el->el_state.lastcmd = cmdnum;
 576
 577                 /* use any return value */
 578                 switch (retval) {
 579                 case CC_CURSOR:
 580                         re_refresh_cursor(el);
 581                         break;
 582
 583                 case CC_REDISPLAY:
 584                         re_clear_lines(el);
 585                         re_clear_display(el);
 586                         /* FALLTHROUGH */
 587
 588                 case CC_REFRESH:
 589                         re_refresh(el);
 590                         break;
 591
 592                 case CC_REFRESH_BEEP:
 593                         re_refresh(el);
 594                         term_beep(el);
 595                         break;
 596
 597                 case CC_NORM:   /* normal char */
 598                         break;
 599
 600                 case CC_ARGHACK:        /* Suggested by Rich Salz */
 601                         /* <rsalz@pineapple.bbn.com> */
 602                         continue;       /* keep going... */
 603
 604                 case CC_EOF:    /* end of file typed */
 605                         if ((el->el_flags & UNBUFFERED) == 0)
 606                                 num = 0;
 607                         else if (num == -1) {
 608                                 *el->el_line.lastchar++ = CONTROL('d');
 609                                 el->el_line.cursor = el->el_line.lastchar;
 610                                 num = 1;
 611                         }
 612                         break;
 613
 614                 case CC_NEWLINE:        /* normal end of line */
 615                         num = (int)(el->el_line.lastchar - el->el_line.buffer);
 616                         break;
 617
 618                 case CC_FATAL:  /* fatal error, reset to known state */
 619 #ifdef DEBUG_READ
 620                         (void) fprintf(el->el_errfile,
 621                             "*** editor fatal ERROR ***\r\n\n");
 622 #endif /* DEBUG_READ */
 623                         /* put (real) cursor in a known place */
 624                         re_clear_display(el);   /* reset the display stuff */
 625                         ch_reset(el, 1);        /* reset the input pointers */
 626                         re_refresh(el); /* print the prompt again */
 627                         break;
 628
 629                 case CC_ERROR:
 630                 default:        /* functions we don't know about */
 631 #ifdef DEBUG_READ
 632                         (void) fprintf(el->el_errfile,
 633                             "*** editor ERROR ***\r\n\n");
 634 #endif /* DEBUG_READ */
 635                         term_beep(el);
 636                         term__flush(el);
 637                         break;
 638                 }
 639                 el->el_state.argument = 1;
 640                 el->el_state.doingarg = 0;
 641                 el->el_chared.c_vcmd.action = NOP;
 642                 if (el->el_flags & UNBUFFERED)
 643                         break;
 644         }
 645
 646         term__flush(el);                /* flush any buffered output */
 647         /* make sure the tty is set up correctly */
 648         if ((el->el_flags & UNBUFFERED) == 0) {
 649                 read_finish(el);
 650                 *nread = num != -1 ? num : 0;
 651         } else {
 652                 *nread = (int)(el->el_line.lastchar - el->el_line.buffer);
 653         }
 654 done:
 655         if (*nread == 0) {
 656                 if (num == -1) {
 657                         *nread = -1;
 658                         errno = el->el_errno;
 659                 }
 660                 return NULL;
 661         } else
 662                 return el->el_line.buffer;
 663 }