contrib/libedit/src/read.c

   1 /*      $NetBSD: read.c,v 1.105 2018/11/25 16:21:04 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 1.105 2018/11/25 16:21:04 christos Exp $");
  41 #endif
  42 #endif /* not lint && not SCCSID */
  43
  44 /*
  45  * read.c: Terminal read functions
  46  */
  47 #include <ctype.h>
  48 #include <errno.h>
  49 #include <fcntl.h>
  50 #include <limits.h>
  51 #include <stdlib.h>
  52 #include <string.h>
  53 #include <unistd.h>
  54
  55 #include "el.h"
  56 #include "fcns.h"
  57 #include "read.h"
  58
  59 #define EL_MAXMACRO     10
  60
  61 struct macros {
  62         wchar_t **macro;
  63         int       level;
  64         int       offset;
  65 };
  66
  67 struct el_read_t {
  68         struct macros    macros;
  69         el_rfunc_t       read_char;     /* Function to read a character. */
  70         int              read_errno;
  71 };
  72
  73 static int      read__fixio(int, int);
  74 static int      read_char(EditLine *, wchar_t *);
  75 static int      read_getcmd(EditLine *, el_action_t *, wchar_t *);
  76 static void     read_clearmacros(struct macros *);
  77 static void     read_pop(struct macros *);
  78 static const wchar_t *noedit_wgets(EditLine *, int *);
  79
  80 /* read_init():
  81  *      Initialize the read stuff
  82  */
  83 libedit_private int
  84 read_init(EditLine *el)
  85 {
  86         struct macros *ma;
  87
  88         if ((el->el_read = el_malloc(sizeof(*el->el_read))) == NULL)
  89                 return -1;
  90
  91         ma = &el->el_read->macros;
  92         if ((ma->macro = el_malloc(EL_MAXMACRO *
  93             sizeof(*ma->macro))) == NULL) {
  94                 free(el->el_read);
  95                 return -1;
  96         }
  97         ma->level = -1;
  98         ma->offset = 0;
  99
 100         /* builtin read_char */
 101         el->el_read->read_char = read_char;
 102         return 0;
 103 }
 104
 105 /* el_read_end():
 106  *      Free the data structures used by the read stuff.
 107  */
 108 libedit_private void
 109 read_end(struct el_read_t *el_read)
 110 {
 111         read_clearmacros(&el_read->macros);
 112         el_free(el_read->macros.macro);
 113         el_read->macros.macro = NULL;
 114         el_free(el_read);
 115 }
 116
 117 /* el_read_setfn():
 118  *      Set the read char function to the one provided.
 119  *      If it is set to EL_BUILTIN_GETCFN, then reset to the builtin one.
 120  */
 121 libedit_private int
 122 el_read_setfn(struct el_read_t *el_read, el_rfunc_t rc)
 123 {
 124         el_read->read_char = (rc == EL_BUILTIN_GETCFN) ? read_char : rc;
 125         return 0;
 126 }
 127
 128
 129 /* el_read_getfn():
 130  *      return the current read char function, or EL_BUILTIN_GETCFN
 131  *      if it is the default one
 132  */
 133 libedit_private el_rfunc_t
 134 el_read_getfn(struct el_read_t *el_read)
 135 {
 136        return el_read->read_char == read_char ?
 137             EL_BUILTIN_GETCFN : el_read->read_char;
 138 }
 139
 140
 141 /* read__fixio():
 142  *      Try to recover from a read error
 143  */
 144 /* ARGSUSED */
 145 static int
 146 read__fixio(int fd __attribute__((__unused__)), int e)
 147 {
 148
 149         switch (e) {
 150         case -1:                /* Make sure that the code is reachable */
 151
 152 #ifdef EWOULDBLOCK
 153         case EWOULDBLOCK:
 154 #ifndef TRY_AGAIN
 155 #define TRY_AGAIN
 156 #endif
 157 #endif /* EWOULDBLOCK */
 158
 159 #if defined(POSIX) && defined(EAGAIN)
 160 #if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
 161         case EAGAIN:
 162 #ifndef TRY_AGAIN
 163 #define TRY_AGAIN
 164 #endif
 165 #endif /* EWOULDBLOCK && EWOULDBLOCK != EAGAIN */
 166 #endif /* POSIX && EAGAIN */
 167
 168                 e = 0;
 169 #ifdef TRY_AGAIN
 170 #if defined(F_SETFL) && defined(O_NDELAY)
 171                 if ((e = fcntl(fd, F_GETFL, 0)) == -1)
 172                         return -1;
 173
 174                 if (fcntl(fd, F_SETFL, e & ~O_NDELAY) == -1)
 175                         return -1;
 176                 else
 177                         e = 1;
 178 #endif /* F_SETFL && O_NDELAY */
 179
 180 #ifdef FIONBIO
 181                 {
 182                         int zero = 0;
 183
 184                         if (ioctl(fd, FIONBIO, &zero) == -1)
 185                                 return -1;
 186                         else
 187                                 e = 1;
 188                 }
 189 #endif /* FIONBIO */
 190
 191 #endif /* TRY_AGAIN */
 192                 return e ? 0 : -1;
 193
 194         case EINTR:
 195                 return 0;
 196
 197         default:
 198                 return -1;
 199         }
 200 }
 201
 202
 203 /* el_push():
 204  *      Push a macro
 205  */
 206 void
 207 el_wpush(EditLine *el, const wchar_t *str)
 208 {
 209         struct macros *ma = &el->el_read->macros;
 210
 211         if (str != NULL && ma->level + 1 < EL_MAXMACRO) {
 212                 ma->level++;
 213                 if ((ma->macro[ma->level] = wcsdup(str)) != NULL)
 214                         return;
 215                 ma->level--;
 216         }
 217         terminal_beep(el);
 218         terminal__flush(el);
 219 }
 220
 221
 222 /* read_getcmd():
 223  *      Get next command from the input stream,
 224  *      return 0 on success or -1 on EOF or error.
 225  *      Character values > 255 are not looked up in the map, but inserted.
 226  */
 227 static int
 228 read_getcmd(EditLine *el, el_action_t *cmdnum, wchar_t *ch)
 229 {
 230         static const wchar_t meta = (wchar_t)0x80;
 231         el_action_t cmd;
 232
 233         do {
 234                 if (el_wgetc(el, ch) != 1)
 235                         return -1;
 236
 237 #ifdef  KANJI
 238                 if ((*ch & meta)) {
 239                         el->el_state.metanext = 0;
 240                         cmd = CcViMap[' '];
 241                         break;
 242                 } else
 243 #endif /* KANJI */
 244
 245                 if (el->el_state.metanext) {
 246                         el->el_state.metanext = 0;
 247                         *ch |= meta;
 248                 }
 249                 if (*ch >= N_KEYS)
 250                         cmd = ED_INSERT;
 251                 else
 252                         cmd = el->el_map.current[(unsigned char) *ch];
 253                 if (cmd == ED_SEQUENCE_LEAD_IN) {
 254                         keymacro_value_t val;
 255                         switch (keymacro_get(el, ch, &val)) {
 256                         case XK_CMD:
 257                                 cmd = val.cmd;
 258                                 break;
 259                         case XK_STR:
 260                                 el_wpush(el, val.str);
 261                                 break;
 262                         case XK_NOD:
 263                                 return -1;
 264                         default:
 265                                 EL_ABORT((el->el_errfile, "Bad XK_ type \n"));
 266                                 break;
 267                         }
 268                 }
 269         } while (cmd == ED_SEQUENCE_LEAD_IN);
 270         *cmdnum = cmd;
 271         return 0;
 272 }
 273
 274 /* read_char():
 275  *      Read a character from the tty.
 276  */
 277 static int
 278 read_char(EditLine *el, wchar_t *cp)
 279 {
 280         ssize_t num_read;
 281         int tried = 0;
 282         char cbuf[MB_LEN_MAX];
 283         size_t cbp = 0;
 284         int save_errno = errno;
 285
 286  again:
 287         el->el_signal->sig_no = 0;
 288         while ((num_read = read(el->el_infd, cbuf + cbp, (size_t)1)) == -1) {
 289                 int e = errno;
 290                 switch (el->el_signal->sig_no) {
 291                 case SIGCONT:
 292                         el_wset(el, EL_REFRESH);
 293                         /*FALLTHROUGH*/
 294                 case SIGWINCH:
 295                         sig_set(el);
 296                         goto again;
 297                 default:
 298                         break;
 299                 }
 300                 if (!tried && read__fixio(el->el_infd, e) == 0) {
 301                         errno = save_errno;
 302                         tried = 1;
 303                 } else {
 304                         errno = e;
 305                         *cp = L'\0';
 306                         return -1;
 307                 }
 308         }
 309
 310         /* Test for EOF */
 311         if (num_read == 0) {
 312                 *cp = L'\0';
 313                 return 0;
 314         }
 315
 316         for (;;) {
 317                 mbstate_t mbs;
 318
 319                 ++cbp;
 320                 /* This only works because UTF8 is stateless. */
 321                 memset(&mbs, 0, sizeof(mbs));
 322                 switch (mbrtowc(cp, cbuf, cbp, &mbs)) {
 323                 case (size_t)-1:
 324                         if (cbp > 1) {
 325                                 /*
 326                                  * Invalid sequence, discard all bytes
 327                                  * except the last one.
 328                                  */
 329                                 cbuf[0] = cbuf[cbp - 1];
 330                                 cbp = 0;
 331                                 break;
 332                         } else {
 333                                 /* Invalid byte, discard it. */
 334                                 cbp = 0;
 335                                 goto again;
 336                         }
 337                 case (size_t)-2:
 338                         if (cbp >= MB_LEN_MAX) {
 339                                 errno = EILSEQ;
 340                                 *cp = L'\0';
 341                                 return -1;
 342                         }
 343                         /* Incomplete sequence, read another byte. */
 344                         goto again;
 345                 default:
 346                         /* Valid character, process it. */
 347                         return 1;
 348                 }
 349         }
 350 }
 351
 352 /* read_pop():
 353  *      Pop a macro from the stack
 354  */
 355 static void
 356 read_pop(struct macros *ma)
 357 {
 358         int i;
 359
 360         el_free(ma->macro[0]);
 361         for (i = 0; i < ma->level; i++)
 362                 ma->macro[i] = ma->macro[i + 1];
 363         ma->level--;
 364         ma->offset = 0;
 365 }
 366
 367 static void
 368 read_clearmacros(struct macros *ma)
 369 {
 370         while (ma->level >= 0)
 371                 el_free(ma->macro[ma->level--]);
 372         ma->offset = 0;
 373 }
 374
 375 /* el_wgetc():
 376  *      Read a wide character
 377  */
 378 int
 379 el_wgetc(EditLine *el, wchar_t *cp)
 380 {
 381         struct macros *ma = &el->el_read->macros;
 382         int num_read;
 383
 384         terminal__flush(el);
 385         for (;;) {
 386                 if (ma->level < 0)
 387                         break;
 388
 389                 if (ma->macro[0][ma->offset] == '\0') {
 390                         read_pop(ma);
 391                         continue;
 392                 }
 393
 394                 *cp = ma->macro[0][ma->offset++];
 395
 396                 if (ma->macro[0][ma->offset] == '\0') {
 397                         /* Needed for QuoteMode On */
 398                         read_pop(ma);
 399                 }
 400
 401                 return 1;
 402         }
 403
 404         if (tty_rawmode(el) < 0)/* make sure the tty is set up correctly */
 405                 return 0;
 406
 407         num_read = (*el->el_read->read_char)(el, cp);
 408
 409         /*
 410          * Remember the original reason of a read failure
 411          * such that el_wgets() can restore it after doing
 412          * various cleanup operation that might change errno.
 413          */
 414         if (num_read < 0)
 415                 el->el_read->read_errno = errno;
 416
 417         return num_read;
 418 }
 419
 420 libedit_private void
 421 read_prepare(EditLine *el)
 422 {
 423         if (el->el_flags & HANDLE_SIGNALS)
 424                 sig_set(el);
 425         if (el->el_flags & NO_TTY)
 426                 return;
 427         if ((el->el_flags & (UNBUFFERED|EDIT_DISABLED)) == UNBUFFERED)
 428                 tty_rawmode(el);
 429
 430         /* This is relatively cheap, and things go terribly wrong if
 431            we have the wrong size. */
 432         el_resize(el);
 433         re_clear_display(el);   /* reset the display stuff */
 434         ch_reset(el);
 435         re_refresh(el);         /* print the prompt */
 436
 437         if (el->el_flags & UNBUFFERED)
 438                 terminal__flush(el);
 439 }
 440
 441 libedit_private void
 442 read_finish(EditLine *el)
 443 {
 444         if ((el->el_flags & UNBUFFERED) == 0)
 445                 (void) tty_cookedmode(el);
 446         if (el->el_flags & HANDLE_SIGNALS)
 447                 sig_clr(el);
 448 }
 449
 450 static const wchar_t *
 451 noedit_wgets(EditLine *el, int *nread)
 452 {
 453         el_line_t       *lp = &el->el_line;
 454         int              num;
 455
 456         while ((num = (*el->el_read->read_char)(el, lp->lastchar)) == 1) {
 457                 if (lp->lastchar + 1 >= lp->limit &&
 458                     !ch_enlargebufs(el, (size_t)2))
 459                         break;
 460                 lp->lastchar++;
 461                 if (el->el_flags & UNBUFFERED ||
 462                     lp->lastchar[-1] == '\r' ||
 463                     lp->lastchar[-1] == '\n')
 464                         break;
 465         }
 466         if (num == -1 && errno == EINTR)
 467                 lp->lastchar = lp->buffer;
 468         lp->cursor = lp->lastchar;
 469         *lp->lastchar = '\0';
 470         *nread = (int)(lp->lastchar - lp->buffer);
 471         return *nread ? lp->buffer : NULL;
 472 }
 473
 474 const wchar_t *
 475 el_wgets(EditLine *el, int *nread)
 476 {
 477         int retval;
 478         el_action_t cmdnum = 0;
 479         int num;                /* how many chars we have read at NL */
 480         wchar_t ch;
 481         int nrb;
 482
 483         if (nread == NULL)
 484                 nread = &nrb;
 485         *nread = 0;
 486         el->el_read->read_errno = 0;
 487
 488         if (el->el_flags & NO_TTY) {
 489                 el->el_line.lastchar = el->el_line.buffer;
 490                 return noedit_wgets(el, nread);
 491         }
 492
 493 #ifdef FIONREAD
 494         if (el->el_tty.t_mode == EX_IO && el->el_read->macros.level < 0) {
 495                 int chrs = 0;
 496
 497                 (void) ioctl(el->el_infd, FIONREAD, &chrs);
 498                 if (chrs == 0) {
 499                         if (tty_rawmode(el) < 0) {
 500                                 errno = 0;
 501                                 *nread = 0;
 502                                 return NULL;
 503                         }
 504                 }
 505         }
 506 #endif /* FIONREAD */
 507
 508         if ((el->el_flags & UNBUFFERED) == 0)
 509                 read_prepare(el);
 510
 511         if (el->el_flags & EDIT_DISABLED) {
 512                 if ((el->el_flags & UNBUFFERED) == 0)
 513                         el->el_line.lastchar = el->el_line.buffer;
 514                 terminal__flush(el);
 515                 return noedit_wgets(el, nread);
 516         }
 517
 518         for (num = -1; num == -1;) {  /* while still editing this line */
 519                 /* if EOF or error */
 520                 if (read_getcmd(el, &cmdnum, &ch) == -1)
 521                         break;
 522                 if ((size_t)cmdnum >= el->el_map.nfunc) /* BUG CHECK command */
 523                         continue;       /* try again */
 524                 /* now do the real command */
 525                 /* vi redo needs these way down the levels... */
 526                 el->el_state.thiscmd = cmdnum;
 527                 el->el_state.thisch = ch;
 528                 if (el->el_map.type == MAP_VI &&
 529                     el->el_map.current == el->el_map.key &&
 530                     el->el_chared.c_redo.pos < el->el_chared.c_redo.lim) {
 531                         if (cmdnum == VI_DELETE_PREV_CHAR &&
 532                             el->el_chared.c_redo.pos != el->el_chared.c_redo.buf
 533                             && iswprint(el->el_chared.c_redo.pos[-1]))
 534                                 el->el_chared.c_redo.pos--;
 535                         else
 536                                 *el->el_chared.c_redo.pos++ = ch;
 537                 }
 538                 retval = (*el->el_map.func[cmdnum]) (el, ch);
 539
 540                 /* save the last command here */
 541                 el->el_state.lastcmd = cmdnum;
 542
 543                 /* use any return value */
 544                 switch (retval) {
 545                 case CC_CURSOR:
 546                         re_refresh_cursor(el);
 547                         break;
 548
 549                 case CC_REDISPLAY:
 550                         re_clear_lines(el);
 551                         re_clear_display(el);
 552                         /* FALLTHROUGH */
 553
 554                 case CC_REFRESH:
 555                         re_refresh(el);
 556                         break;
 557
 558                 case CC_REFRESH_BEEP:
 559                         re_refresh(el);
 560                         terminal_beep(el);
 561                         break;
 562
 563                 case CC_NORM:   /* normal char */
 564                         break;
 565
 566                 case CC_ARGHACK:        /* Suggested by Rich Salz */
 567                         /* <rsalz@pineapple.bbn.com> */
 568                         continue;       /* keep going... */
 569
 570                 case CC_EOF:    /* end of file typed */
 571                         if ((el->el_flags & UNBUFFERED) == 0)
 572                                 num = 0;
 573                         else if (num == -1) {
 574                                 *el->el_line.lastchar++ = CONTROL('d');
 575                                 el->el_line.cursor = el->el_line.lastchar;
 576                                 num = 1;
 577                         }
 578                         break;
 579
 580                 case CC_NEWLINE:        /* normal end of line */
 581                         num = (int)(el->el_line.lastchar - el->el_line.buffer);
 582                         break;
 583
 584                 case CC_FATAL:  /* fatal error, reset to known state */
 585                         /* put (real) cursor in a known place */
 586                         re_clear_display(el);   /* reset the display stuff */
 587                         ch_reset(el);   /* reset the input pointers */
 588                         read_clearmacros(&el->el_read->macros);
 589                         re_refresh(el); /* print the prompt again */
 590                         break;
 591
 592                 case CC_ERROR:
 593                 default:        /* functions we don't know about */
 594                         terminal_beep(el);
 595                         terminal__flush(el);
 596                         break;
 597                 }
 598                 el->el_state.argument = 1;
 599                 el->el_state.doingarg = 0;
 600                 el->el_chared.c_vcmd.action = NOP;
 601                 if (el->el_flags & UNBUFFERED)
 602                         break;
 603         }
 604
 605         terminal__flush(el);            /* flush any buffered output */
 606         /* make sure the tty is set up correctly */
 607         if ((el->el_flags & UNBUFFERED) == 0) {
 608                 read_finish(el);
 609                 *nread = num != -1 ? num : 0;
 610         } else
 611                 *nread = (int)(el->el_line.lastchar - el->el_line.buffer);
 612
 613         if (*nread == 0) {
 614                 if (num == -1) {
 615                         *nread = -1;
 616                         if (el->el_read->read_errno)
 617                                 errno = el->el_read->read_errno;
 618                 }
 619                 return NULL;
 620         } else
 621                 return el->el_line.buffer;
 622 }