contrib/libedit/read.c

   1 /*      $NetBSD: read.c,v 1.108 2022/10/30 19:11:31 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 1.108 2022/10/30 19:11:31 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_calloc(EL_MAXMACRO, sizeof(*ma->macro))) == NULL)
  93                 goto out;
  94         ma->level = -1;
  95         ma->offset = 0;
  96
  97         /* builtin read_char */
  98         el->el_read->read_char = read_char;
  99         return 0;
 100 out:
 101         read_end(el);
 102         return -1;
 103 }
 104
 105 /* el_read_end():
 106  *      Free the data structures used by the read stuff.
 107  */
 108 libedit_private void
 109 read_end(EditLine *el)
 110 {
 111
 112         read_clearmacros(&el->el_read->macros);
 113         el_free(el->el_read->macros.macro);
 114         el->el_read->macros.macro = NULL;
 115         el_free(el->el_read);
 116         el->el_read = NULL;
 117 }
 118
 119 /* el_read_setfn():
 120  *      Set the read char function to the one provided.
 121  *      If it is set to EL_BUILTIN_GETCFN, then reset to the builtin one.
 122  */
 123 libedit_private int
 124 el_read_setfn(struct el_read_t *el_read, el_rfunc_t rc)
 125 {
 126         el_read->read_char = (rc == EL_BUILTIN_GETCFN) ? read_char : rc;
 127         return 0;
 128 }
 129
 130
 131 /* el_read_getfn():
 132  *      return the current read char function, or EL_BUILTIN_GETCFN
 133  *      if it is the default one
 134  */
 135 libedit_private el_rfunc_t
 136 el_read_getfn(struct el_read_t *el_read)
 137 {
 138        return el_read->read_char == read_char ?
 139             EL_BUILTIN_GETCFN : el_read->read_char;
 140 }
 141
 142
 143 /* read__fixio():
 144  *      Try to recover from a read error
 145  */
 146 /* ARGSUSED */
 147 static int
 148 read__fixio(int fd __attribute__((__unused__)), int e)
 149 {
 150
 151         switch (e) {
 152         case -1:                /* Make sure that the code is reachable */
 153
 154 #ifdef EWOULDBLOCK
 155         case EWOULDBLOCK:
 156 #ifndef TRY_AGAIN
 157 #define TRY_AGAIN
 158 #endif
 159 #endif /* EWOULDBLOCK */
 160
 161 #if defined(POSIX) && defined(EAGAIN)
 162 #if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
 163         case EAGAIN:
 164 #ifndef TRY_AGAIN
 165 #define TRY_AGAIN
 166 #endif
 167 #endif /* EWOULDBLOCK && EWOULDBLOCK != EAGAIN */
 168 #endif /* POSIX && EAGAIN */
 169
 170                 e = 0;
 171 #ifdef TRY_AGAIN
 172 #if defined(F_SETFL) && defined(O_NDELAY)
 173                 if ((e = fcntl(fd, F_GETFL, 0)) == -1)
 174                         return -1;
 175
 176                 if (fcntl(fd, F_SETFL, e & ~O_NDELAY) == -1)
 177                         return -1;
 178                 else
 179                         e = 1;
 180 #endif /* F_SETFL && O_NDELAY */
 181
 182 #ifdef FIONBIO
 183                 {
 184                         int zero = 0;
 185
 186                         if (ioctl(fd, FIONBIO, &zero) == -1)
 187                                 return -1;
 188                         else
 189                                 e = 1;
 190                 }
 191 #endif /* FIONBIO */
 192
 193 #endif /* TRY_AGAIN */
 194                 return e ? 0 : -1;
 195
 196         case EINTR:
 197                 return 0;
 198
 199         default:
 200                 return -1;
 201         }
 202 }
 203
 204
 205 /* el_push():
 206  *      Push a macro
 207  */
 208 void
 209 el_wpush(EditLine *el, const wchar_t *str)
 210 {
 211         struct macros *ma = &el->el_read->macros;
 212
 213         if (str != NULL && ma->level + 1 < EL_MAXMACRO) {
 214                 ma->level++;
 215                 if ((ma->macro[ma->level] = wcsdup(str)) != NULL)
 216                         return;
 217                 ma->level--;
 218         }
 219         terminal_beep(el);
 220         terminal__flush(el);
 221 }
 222
 223
 224 /* read_getcmd():
 225  *      Get next command from the input stream,
 226  *      return 0 on success or -1 on EOF or error.
 227  *      Character values > 255 are not looked up in the map, but inserted.
 228  */
 229 static int
 230 read_getcmd(EditLine *el, el_action_t *cmdnum, wchar_t *ch)
 231 {
 232         static const wchar_t meta = (wchar_t)0x80;
 233         el_action_t cmd;
 234
 235         do {
 236                 if (el_wgetc(el, ch) != 1)
 237                         return -1;
 238
 239 #ifdef  KANJI
 240                 if ((*ch & meta)) {
 241                         el->el_state.metanext = 0;
 242                         cmd = CcViMap[' '];
 243                         break;
 244                 } else
 245 #endif /* KANJI */
 246
 247                 if (el->el_state.metanext) {
 248                         el->el_state.metanext = 0;
 249                         *ch |= meta;
 250                 }
 251                 if (*ch >= N_KEYS)
 252                         cmd = ED_INSERT;
 253                 else
 254                         cmd = el->el_map.current[(unsigned char) *ch];
 255                 if (cmd == ED_SEQUENCE_LEAD_IN) {
 256                         keymacro_value_t val;
 257                         switch (keymacro_get(el, ch, &val)) {
 258                         case XK_CMD:
 259                                 cmd = val.cmd;
 260                                 break;
 261                         case XK_STR:
 262                                 el_wpush(el, val.str);
 263                                 break;
 264                         case XK_NOD:
 265                                 return -1;
 266                         default:
 267                                 EL_ABORT((el->el_errfile, "Bad XK_ type \n"));
 268                                 break;
 269                         }
 270                 }
 271         } while (cmd == ED_SEQUENCE_LEAD_IN);
 272         *cmdnum = cmd;
 273         return 0;
 274 }
 275
 276 /* read_char():
 277  *      Read a character from the tty.
 278  */
 279 static int
 280 read_char(EditLine *el, wchar_t *cp)
 281 {
 282         ssize_t num_read;
 283         int tried = (el->el_flags & FIXIO) == 0;
 284         char cbuf[MB_LEN_MAX];
 285         size_t cbp = 0;
 286         int save_errno = errno;
 287
 288  again:
 289         el->el_signal->sig_no = 0;
 290         while ((num_read = read(el->el_infd, cbuf + cbp, (size_t)1)) == -1) {
 291                 int e = errno;
 292                 switch (el->el_signal->sig_no) {
 293                 case SIGCONT:
 294                         el_wset(el, EL_REFRESH);
 295                         /*FALLTHROUGH*/
 296                 case SIGWINCH:
 297                         sig_set(el);
 298                         goto again;
 299                 default:
 300                         break;
 301                 }
 302                 if (!tried && read__fixio(el->el_infd, e) == 0) {
 303                         errno = save_errno;
 304                         tried = 1;
 305                 } else {
 306                         errno = e;
 307                         *cp = L'\0';
 308                         return -1;
 309                 }
 310         }
 311
 312         /* Test for EOF */
 313         if (num_read == 0) {
 314                 *cp = L'\0';
 315                 return 0;
 316         }
 317
 318         for (;;) {
 319                 mbstate_t mbs;
 320
 321                 ++cbp;
 322                 /* This only works because UTF8 is stateless. */
 323                 memset(&mbs, 0, sizeof(mbs));
 324                 switch (mbrtowc(cp, cbuf, cbp, &mbs)) {
 325                 case (size_t)-1:
 326                         if (cbp > 1) {
 327                                 /*
 328                                  * Invalid sequence, discard all bytes
 329                                  * except the last one.
 330                                  */
 331                                 cbuf[0] = cbuf[cbp - 1];
 332                                 cbp = 0;
 333                                 break;
 334                         } else {
 335                                 /* Invalid byte, discard it. */
 336                                 cbp = 0;
 337                                 goto again;
 338                         }
 339                 case (size_t)-2:
 340                         if (cbp >= MB_LEN_MAX) {
 341                                 errno = EILSEQ;
 342                                 *cp = L'\0';
 343                                 return -1;
 344                         }
 345                         /* Incomplete sequence, read another byte. */
 346                         goto again;
 347                 default:
 348                         /* Valid character, process it. */
 349                         return 1;
 350                 }
 351         }
 352 }
 353
 354 /* read_pop():
 355  *      Pop a macro from the stack
 356  */
 357 static void
 358 read_pop(struct macros *ma)
 359 {
 360         int i;
 361
 362         el_free(ma->macro[0]);
 363         for (i = 0; i < ma->level; i++)
 364                 ma->macro[i] = ma->macro[i + 1];
 365         ma->level--;
 366         ma->offset = 0;
 367 }
 368
 369 static void
 370 read_clearmacros(struct macros *ma)
 371 {
 372         while (ma->level >= 0)
 373                 el_free(ma->macro[ma->level--]);
 374         ma->offset = 0;
 375 }
 376
 377 /* el_wgetc():
 378  *      Read a wide character
 379  */
 380 int
 381 el_wgetc(EditLine *el, wchar_t *cp)
 382 {
 383         struct macros *ma = &el->el_read->macros;
 384         int num_read;
 385
 386         terminal__flush(el);
 387         for (;;) {
 388                 if (ma->level < 0)
 389                         break;
 390
 391                 if (ma->macro[0][ma->offset] == '\0') {
 392                         read_pop(ma);
 393                         continue;
 394                 }
 395
 396                 *cp = ma->macro[0][ma->offset++];
 397
 398                 if (ma->macro[0][ma->offset] == '\0') {
 399                         /* Needed for QuoteMode On */
 400                         read_pop(ma);
 401                 }
 402
 403                 return 1;
 404         }
 405
 406         if (tty_rawmode(el) < 0)/* make sure the tty is set up correctly */
 407                 return 0;
 408
 409         num_read = (*el->el_read->read_char)(el, cp);
 410
 411         /*
 412          * Remember the original reason of a read failure
 413          * such that el_wgets() can restore it after doing
 414          * various cleanup operation that might change errno.
 415          */
 416         if (num_read < 0)
 417                 el->el_read->read_errno = errno;
 418
 419         return num_read;
 420 }
 421
 422 libedit_private void
 423 read_prepare(EditLine *el)
 424 {
 425         if (el->el_flags & HANDLE_SIGNALS)
 426                 sig_set(el);
 427         if (el->el_flags & NO_TTY)
 428                 return;
 429         if ((el->el_flags & (UNBUFFERED|EDIT_DISABLED)) == UNBUFFERED)
 430                 tty_rawmode(el);
 431
 432         /* This is relatively cheap, and things go terribly wrong if
 433            we have the wrong size. */
 434         el_resize(el);
 435         re_clear_display(el);   /* reset the display stuff */
 436         ch_reset(el);
 437         re_refresh(el);         /* print the prompt */
 438
 439         if (el->el_flags & UNBUFFERED)
 440                 terminal__flush(el);
 441 }
 442
 443 libedit_private void
 444 read_finish(EditLine *el)
 445 {
 446         if ((el->el_flags & UNBUFFERED) == 0)
 447                 (void) tty_cookedmode(el);
 448         if (el->el_flags & HANDLE_SIGNALS)
 449                 sig_clr(el);
 450 }
 451
 452 static const wchar_t *
 453 noedit_wgets(EditLine *el, int *nread)
 454 {
 455         el_line_t       *lp = &el->el_line;
 456         int              num;
 457
 458         while ((num = (*el->el_read->read_char)(el, lp->lastchar)) == 1) {
 459                 if (lp->lastchar + 1 >= lp->limit &&
 460                     !ch_enlargebufs(el, (size_t)2))
 461                         break;
 462                 lp->lastchar++;
 463                 if (el->el_flags & UNBUFFERED ||
 464                     lp->lastchar[-1] == '\r' ||
 465                     lp->lastchar[-1] == '\n')
 466                         break;
 467         }
 468         if (num == -1 && errno == EINTR)
 469                 lp->lastchar = lp->buffer;
 470         lp->cursor = lp->lastchar;
 471         *lp->lastchar = '\0';
 472         *nread = (int)(lp->lastchar - lp->buffer);
 473         return *nread ? lp->buffer : NULL;
 474 }
 475
 476 const wchar_t *
 477 el_wgets(EditLine *el, int *nread)
 478 {
 479         int retval;
 480         el_action_t cmdnum = 0;
 481         int num;                /* how many chars we have read at NL */
 482         wchar_t ch;
 483         int nrb;
 484
 485         if (nread == NULL)
 486                 nread = &nrb;
 487         *nread = 0;
 488         el->el_read->read_errno = 0;
 489
 490         if (el->el_flags & NO_TTY) {
 491                 el->el_line.lastchar = el->el_line.buffer;
 492                 return noedit_wgets(el, nread);
 493         }
 494
 495 #ifdef FIONREAD
 496         if (el->el_tty.t_mode == EX_IO && el->el_read->macros.level < 0) {
 497                 int chrs = 0;
 498
 499                 (void) ioctl(el->el_infd, FIONREAD, &chrs);
 500                 if (chrs == 0) {
 501                         if (tty_rawmode(el) < 0) {
 502                                 errno = 0;
 503                                 *nread = 0;
 504                                 return NULL;
 505                         }
 506                 }
 507         }
 508 #endif /* FIONREAD */
 509
 510         if ((el->el_flags & UNBUFFERED) == 0)
 511                 read_prepare(el);
 512
 513         if (el->el_flags & EDIT_DISABLED) {
 514                 if ((el->el_flags & UNBUFFERED) == 0)
 515                         el->el_line.lastchar = el->el_line.buffer;
 516                 terminal__flush(el);
 517                 return noedit_wgets(el, nread);
 518         }
 519
 520         for (num = -1; num == -1;) {  /* while still editing this line */
 521                 /* if EOF or error */
 522                 if (read_getcmd(el, &cmdnum, &ch) == -1)
 523                         break;
 524                 if ((size_t)cmdnum >= el->el_map.nfunc) /* BUG CHECK command */
 525                         continue;       /* try again */
 526                 /* now do the real command */
 527                 /* vi redo needs these way down the levels... */
 528                 el->el_state.thiscmd = cmdnum;
 529                 el->el_state.thisch = ch;
 530                 if (el->el_map.type == MAP_VI &&
 531                     el->el_map.current == el->el_map.key &&
 532                     el->el_chared.c_redo.pos < el->el_chared.c_redo.lim) {
 533                         if (cmdnum == VI_DELETE_PREV_CHAR &&
 534                             el->el_chared.c_redo.pos != el->el_chared.c_redo.buf
 535                             && iswprint(el->el_chared.c_redo.pos[-1]))
 536                                 el->el_chared.c_redo.pos--;
 537                         else
 538                                 *el->el_chared.c_redo.pos++ = ch;
 539                 }
 540                 retval = (*el->el_map.func[cmdnum]) (el, ch);
 541
 542                 /* save the last command here */
 543                 el->el_state.lastcmd = cmdnum;
 544
 545                 /* use any return value */
 546                 switch (retval) {
 547                 case CC_CURSOR:
 548                         re_refresh_cursor(el);
 549                         break;
 550
 551                 case CC_REDISPLAY:
 552                         re_clear_lines(el);
 553                         re_clear_display(el);
 554                         /* FALLTHROUGH */
 555
 556                 case CC_REFRESH:
 557                         re_refresh(el);
 558                         break;
 559
 560                 case CC_REFRESH_BEEP:
 561                         re_refresh(el);
 562                         terminal_beep(el);
 563                         break;
 564
 565                 case CC_NORM:   /* normal char */
 566                         break;
 567
 568                 case CC_ARGHACK:        /* Suggested by Rich Salz */
 569                         /* <rsalz@pineapple.bbn.com> */
 570                         continue;       /* keep going... */
 571
 572                 case CC_EOF:    /* end of file typed */
 573                         if ((el->el_flags & UNBUFFERED) == 0)
 574                                 num = 0;
 575                         else if (num == -1) {
 576                                 *el->el_line.lastchar++ = CONTROL('d');
 577                                 el->el_line.cursor = el->el_line.lastchar;
 578                                 num = 1;
 579                         }
 580                         break;
 581
 582                 case CC_NEWLINE:        /* normal end of line */
 583                         num = (int)(el->el_line.lastchar - el->el_line.buffer);
 584                         break;
 585
 586                 case CC_FATAL:  /* fatal error, reset to known state */
 587                         /* put (real) cursor in a known place */
 588                         re_clear_display(el);   /* reset the display stuff */
 589                         ch_reset(el);   /* reset the input pointers */
 590                         read_clearmacros(&el->el_read->macros);
 591                         re_refresh(el); /* print the prompt again */
 592                         break;
 593
 594                 case CC_ERROR:
 595                 default:        /* functions we don't know about */
 596                         terminal_beep(el);
 597                         terminal__flush(el);
 598                         break;
 599                 }
 600                 el->el_state.argument = 1;
 601                 el->el_state.doingarg = 0;
 602                 el->el_chared.c_vcmd.action = NOP;
 603                 if (el->el_flags & UNBUFFERED)
 604                         break;
 605         }
 606
 607         terminal__flush(el);            /* flush any buffered output */
 608         /* make sure the tty is set up correctly */
 609         if ((el->el_flags & UNBUFFERED) == 0) {
 610                 read_finish(el);
 611                 *nread = num != -1 ? num : 0;
 612         } else
 613                 *nread = (int)(el->el_line.lastchar - el->el_line.buffer);
 614
 615         if (*nread == 0) {
 616                 if (num == -1) {
 617                         *nread = -1;
 618                         if (el->el_read->read_errno)
 619                                 errno = el->el_read->read_errno;
 620                 }
 621                 return NULL;
 622         } else
 623                 return el->el_line.buffer;
 624 }