contrib/libedit/read.c

   1 /*      $NetBSD: read.c,v 1.106 2019/07/23 10:18:52 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 1.106 2019/07/23 10:18:52 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                 free(el->el_read);
  94                 return -1;
  95         }
  96         ma->level = -1;
  97         ma->offset = 0;
  98
  99         /* builtin read_char */
 100         el->el_read->read_char = read_char;
 101         return 0;
 102 }
 103
 104 /* el_read_end():
 105  *      Free the data structures used by the read stuff.
 106  */
 107 libedit_private void
 108 read_end(struct el_read_t *el_read)
 109 {
 110         read_clearmacros(&el_read->macros);
 111         el_free(el_read->macros.macro);
 112         el_read->macros.macro = NULL;
 113         el_free(el_read);
 114 }
 115
 116 /* el_read_setfn():
 117  *      Set the read char function to the one provided.
 118  *      If it is set to EL_BUILTIN_GETCFN, then reset to the builtin one.
 119  */
 120 libedit_private int
 121 el_read_setfn(struct el_read_t *el_read, el_rfunc_t rc)
 122 {
 123         el_read->read_char = (rc == EL_BUILTIN_GETCFN) ? read_char : rc;
 124         return 0;
 125 }
 126
 127
 128 /* el_read_getfn():
 129  *      return the current read char function, or EL_BUILTIN_GETCFN
 130  *      if it is the default one
 131  */
 132 libedit_private el_rfunc_t
 133 el_read_getfn(struct el_read_t *el_read)
 134 {
 135        return el_read->read_char == read_char ?
 136             EL_BUILTIN_GETCFN : el_read->read_char;
 137 }
 138
 139
 140 /* read__fixio():
 141  *      Try to recover from a read error
 142  */
 143 /* ARGSUSED */
 144 static int
 145 read__fixio(int fd __attribute__((__unused__)), int e)
 146 {
 147
 148         switch (e) {
 149         case -1:                /* Make sure that the code is reachable */
 150
 151 #ifdef EWOULDBLOCK
 152         case EWOULDBLOCK:
 153 #ifndef TRY_AGAIN
 154 #define TRY_AGAIN
 155 #endif
 156 #endif /* EWOULDBLOCK */
 157
 158 #if defined(POSIX) && defined(EAGAIN)
 159 #if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
 160         case EAGAIN:
 161 #ifndef TRY_AGAIN
 162 #define TRY_AGAIN
 163 #endif
 164 #endif /* EWOULDBLOCK && EWOULDBLOCK != EAGAIN */
 165 #endif /* POSIX && EAGAIN */
 166
 167                 e = 0;
 168 #ifdef TRY_AGAIN
 169 #if defined(F_SETFL) && defined(O_NDELAY)
 170                 if ((e = fcntl(fd, F_GETFL, 0)) == -1)
 171                         return -1;
 172
 173                 if (fcntl(fd, F_SETFL, e & ~O_NDELAY) == -1)
 174                         return -1;
 175                 else
 176                         e = 1;
 177 #endif /* F_SETFL && O_NDELAY */
 178
 179 #ifdef FIONBIO
 180                 {
 181                         int zero = 0;
 182
 183                         if (ioctl(fd, FIONBIO, &zero) == -1)
 184                                 return -1;
 185                         else
 186                                 e = 1;
 187                 }
 188 #endif /* FIONBIO */
 189
 190 #endif /* TRY_AGAIN */
 191                 return e ? 0 : -1;
 192
 193         case EINTR:
 194                 return 0;
 195
 196         default:
 197                 return -1;
 198         }
 199 }
 200
 201
 202 /* el_push():
 203  *      Push a macro
 204  */
 205 void
 206 el_wpush(EditLine *el, const wchar_t *str)
 207 {
 208         struct macros *ma = &el->el_read->macros;
 209
 210         if (str != NULL && ma->level + 1 < EL_MAXMACRO) {
 211                 ma->level++;
 212                 if ((ma->macro[ma->level] = wcsdup(str)) != NULL)
 213                         return;
 214                 ma->level--;
 215         }
 216         terminal_beep(el);
 217         terminal__flush(el);
 218 }
 219
 220
 221 /* read_getcmd():
 222  *      Get next command from the input stream,
 223  *      return 0 on success or -1 on EOF or error.
 224  *      Character values > 255 are not looked up in the map, but inserted.
 225  */
 226 static int
 227 read_getcmd(EditLine *el, el_action_t *cmdnum, wchar_t *ch)
 228 {
 229         static const wchar_t meta = (wchar_t)0x80;
 230         el_action_t cmd;
 231
 232         do {
 233                 if (el_wgetc(el, ch) != 1)
 234                         return -1;
 235
 236 #ifdef  KANJI
 237                 if ((*ch & meta)) {
 238                         el->el_state.metanext = 0;
 239                         cmd = CcViMap[' '];
 240                         break;
 241                 } else
 242 #endif /* KANJI */
 243
 244                 if (el->el_state.metanext) {
 245                         el->el_state.metanext = 0;
 246                         *ch |= meta;
 247                 }
 248                 if (*ch >= N_KEYS)
 249                         cmd = ED_INSERT;
 250                 else
 251                         cmd = el->el_map.current[(unsigned char) *ch];
 252                 if (cmd == ED_SEQUENCE_LEAD_IN) {
 253                         keymacro_value_t val;
 254                         switch (keymacro_get(el, ch, &val)) {
 255                         case XK_CMD:
 256                                 cmd = val.cmd;
 257                                 break;
 258                         case XK_STR:
 259                                 el_wpush(el, val.str);
 260                                 break;
 261                         case XK_NOD:
 262                                 return -1;
 263                         default:
 264                                 EL_ABORT((el->el_errfile, "Bad XK_ type \n"));
 265                                 break;
 266                         }
 267                 }
 268         } while (cmd == ED_SEQUENCE_LEAD_IN);
 269         *cmdnum = cmd;
 270         return 0;
 271 }
 272
 273 /* read_char():
 274  *      Read a character from the tty.
 275  */
 276 static int
 277 read_char(EditLine *el, wchar_t *cp)
 278 {
 279         ssize_t num_read;
 280         int tried = 0;
 281         char cbuf[MB_LEN_MAX];
 282         size_t cbp = 0;
 283         int save_errno = errno;
 284
 285  again:
 286         el->el_signal->sig_no = 0;
 287         while ((num_read = read(el->el_infd, cbuf + cbp, (size_t)1)) == -1) {
 288                 int e = errno;
 289                 switch (el->el_signal->sig_no) {
 290                 case SIGCONT:
 291                         el_wset(el, EL_REFRESH);
 292                         /*FALLTHROUGH*/
 293                 case SIGWINCH:
 294                         sig_set(el);
 295                         goto again;
 296                 default:
 297                         break;
 298                 }
 299                 if (!tried && read__fixio(el->el_infd, e) == 0) {
 300                         errno = save_errno;
 301                         tried = 1;
 302                 } else {
 303                         errno = e;
 304                         *cp = L'\0';
 305                         return -1;
 306                 }
 307         }
 308
 309         /* Test for EOF */
 310         if (num_read == 0) {
 311                 *cp = L'\0';
 312                 return 0;
 313         }
 314
 315         for (;;) {
 316                 mbstate_t mbs;
 317
 318                 ++cbp;
 319                 /* This only works because UTF8 is stateless. */
 320                 memset(&mbs, 0, sizeof(mbs));
 321                 switch (mbrtowc(cp, cbuf, cbp, &mbs)) {
 322                 case (size_t)-1:
 323                         if (cbp > 1) {
 324                                 /*
 325                                  * Invalid sequence, discard all bytes
 326                                  * except the last one.
 327                                  */
 328                                 cbuf[0] = cbuf[cbp - 1];
 329                                 cbp = 0;
 330                                 break;
 331                         } else {
 332                                 /* Invalid byte, discard it. */
 333                                 cbp = 0;
 334                                 goto again;
 335                         }
 336                 case (size_t)-2:
 337                         if (cbp >= MB_LEN_MAX) {
 338                                 errno = EILSEQ;
 339                                 *cp = L'\0';
 340                                 return -1;
 341                         }
 342                         /* Incomplete sequence, read another byte. */
 343                         goto again;
 344                 default:
 345                         /* Valid character, process it. */
 346                         return 1;
 347                 }
 348         }
 349 }
 350
 351 /* read_pop():
 352  *      Pop a macro from the stack
 353  */
 354 static void
 355 read_pop(struct macros *ma)
 356 {
 357         int i;
 358
 359         el_free(ma->macro[0]);
 360         for (i = 0; i < ma->level; i++)
 361                 ma->macro[i] = ma->macro[i + 1];
 362         ma->level--;
 363         ma->offset = 0;
 364 }
 365
 366 static void
 367 read_clearmacros(struct macros *ma)
 368 {
 369         while (ma->level >= 0)
 370                 el_free(ma->macro[ma->level--]);
 371         ma->offset = 0;
 372 }
 373
 374 /* el_wgetc():
 375  *      Read a wide character
 376  */
 377 int
 378 el_wgetc(EditLine *el, wchar_t *cp)
 379 {
 380         struct macros *ma = &el->el_read->macros;
 381         int num_read;
 382
 383         terminal__flush(el);
 384         for (;;) {
 385                 if (ma->level < 0)
 386                         break;
 387
 388                 if (ma->macro[0][ma->offset] == '\0') {
 389                         read_pop(ma);
 390                         continue;
 391                 }
 392
 393                 *cp = ma->macro[0][ma->offset++];
 394
 395                 if (ma->macro[0][ma->offset] == '\0') {
 396                         /* Needed for QuoteMode On */
 397                         read_pop(ma);
 398                 }
 399
 400                 return 1;
 401         }
 402
 403         if (tty_rawmode(el) < 0)/* make sure the tty is set up correctly */
 404                 return 0;
 405
 406         num_read = (*el->el_read->read_char)(el, cp);
 407
 408         /*
 409          * Remember the original reason of a read failure
 410          * such that el_wgets() can restore it after doing
 411          * various cleanup operation that might change errno.
 412          */
 413         if (num_read < 0)
 414                 el->el_read->read_errno = errno;
 415
 416         return num_read;
 417 }
 418
 419 libedit_private void
 420 read_prepare(EditLine *el)
 421 {
 422         if (el->el_flags & HANDLE_SIGNALS)
 423                 sig_set(el);
 424         if (el->el_flags & NO_TTY)
 425                 return;
 426         if ((el->el_flags & (UNBUFFERED|EDIT_DISABLED)) == UNBUFFERED)
 427                 tty_rawmode(el);
 428
 429         /* This is relatively cheap, and things go terribly wrong if
 430            we have the wrong size. */
 431         el_resize(el);
 432         re_clear_display(el);   /* reset the display stuff */
 433         ch_reset(el);
 434         re_refresh(el);         /* print the prompt */
 435
 436         if (el->el_flags & UNBUFFERED)
 437                 terminal__flush(el);
 438 }
 439
 440 libedit_private void
 441 read_finish(EditLine *el)
 442 {
 443         if ((el->el_flags & UNBUFFERED) == 0)
 444                 (void) tty_cookedmode(el);
 445         if (el->el_flags & HANDLE_SIGNALS)
 446                 sig_clr(el);
 447 }
 448
 449 static const wchar_t *
 450 noedit_wgets(EditLine *el, int *nread)
 451 {
 452         el_line_t       *lp = &el->el_line;
 453         int              num;
 454
 455         while ((num = (*el->el_read->read_char)(el, lp->lastchar)) == 1) {
 456                 if (lp->lastchar + 1 >= lp->limit &&
 457                     !ch_enlargebufs(el, (size_t)2))
 458                         break;
 459                 lp->lastchar++;
 460                 if (el->el_flags & UNBUFFERED ||
 461                     lp->lastchar[-1] == '\r' ||
 462                     lp->lastchar[-1] == '\n')
 463                         break;
 464         }
 465         if (num == -1 && errno == EINTR)
 466                 lp->lastchar = lp->buffer;
 467         lp->cursor = lp->lastchar;
 468         *lp->lastchar = '\0';
 469         *nread = (int)(lp->lastchar - lp->buffer);
 470         return *nread ? lp->buffer : NULL;
 471 }
 472
 473 const wchar_t *
 474 el_wgets(EditLine *el, int *nread)
 475 {
 476         int retval;
 477         el_action_t cmdnum = 0;
 478         int num;                /* how many chars we have read at NL */
 479         wchar_t ch;
 480         int nrb;
 481
 482         if (nread == NULL)
 483                 nread = &nrb;
 484         *nread = 0;
 485         el->el_read->read_errno = 0;
 486
 487         if (el->el_flags & NO_TTY) {
 488                 el->el_line.lastchar = el->el_line.buffer;
 489                 return noedit_wgets(el, nread);
 490         }
 491
 492 #ifdef FIONREAD
 493         if (el->el_tty.t_mode == EX_IO && el->el_read->macros.level < 0) {
 494                 int chrs = 0;
 495
 496                 (void) ioctl(el->el_infd, FIONREAD, &chrs);
 497                 if (chrs == 0) {
 498                         if (tty_rawmode(el) < 0) {
 499                                 errno = 0;
 500                                 *nread = 0;
 501                                 return NULL;
 502                         }
 503                 }
 504         }
 505 #endif /* FIONREAD */
 506
 507         if ((el->el_flags & UNBUFFERED) == 0)
 508                 read_prepare(el);
 509
 510         if (el->el_flags & EDIT_DISABLED) {
 511                 if ((el->el_flags & UNBUFFERED) == 0)
 512                         el->el_line.lastchar = el->el_line.buffer;
 513                 terminal__flush(el);
 514                 return noedit_wgets(el, nread);
 515         }
 516
 517         for (num = -1; num == -1;) {  /* while still editing this line */
 518                 /* if EOF or error */
 519                 if (read_getcmd(el, &cmdnum, &ch) == -1)
 520                         break;
 521                 if ((size_t)cmdnum >= el->el_map.nfunc) /* BUG CHECK command */
 522                         continue;       /* try again */
 523                 /* now do the real command */
 524                 /* vi redo needs these way down the levels... */
 525                 el->el_state.thiscmd = cmdnum;
 526                 el->el_state.thisch = ch;
 527                 if (el->el_map.type == MAP_VI &&
 528                     el->el_map.current == el->el_map.key &&
 529                     el->el_chared.c_redo.pos < el->el_chared.c_redo.lim) {
 530                         if (cmdnum == VI_DELETE_PREV_CHAR &&
 531                             el->el_chared.c_redo.pos != el->el_chared.c_redo.buf
 532                             && iswprint(el->el_chared.c_redo.pos[-1]))
 533                                 el->el_chared.c_redo.pos--;
 534                         else
 535                                 *el->el_chared.c_redo.pos++ = ch;
 536                 }
 537                 retval = (*el->el_map.func[cmdnum]) (el, ch);
 538
 539                 /* save the last command here */
 540                 el->el_state.lastcmd = cmdnum;
 541
 542                 /* use any return value */
 543                 switch (retval) {
 544                 case CC_CURSOR:
 545                         re_refresh_cursor(el);
 546                         break;
 547
 548                 case CC_REDISPLAY:
 549                         re_clear_lines(el);
 550                         re_clear_display(el);
 551                         /* FALLTHROUGH */
 552
 553                 case CC_REFRESH:
 554                         re_refresh(el);
 555                         break;
 556
 557                 case CC_REFRESH_BEEP:
 558                         re_refresh(el);
 559                         terminal_beep(el);
 560                         break;
 561
 562                 case CC_NORM:   /* normal char */
 563                         break;
 564
 565                 case CC_ARGHACK:        /* Suggested by Rich Salz */
 566                         /* <rsalz@pineapple.bbn.com> */
 567                         continue;       /* keep going... */
 568
 569                 case CC_EOF:    /* end of file typed */
 570                         if ((el->el_flags & UNBUFFERED) == 0)
 571                                 num = 0;
 572                         else if (num == -1) {
 573                                 *el->el_line.lastchar++ = CONTROL('d');
 574                                 el->el_line.cursor = el->el_line.lastchar;
 575                                 num = 1;
 576                         }
 577                         break;
 578
 579                 case CC_NEWLINE:        /* normal end of line */
 580                         num = (int)(el->el_line.lastchar - el->el_line.buffer);
 581                         break;
 582
 583                 case CC_FATAL:  /* fatal error, reset to known state */
 584                         /* put (real) cursor in a known place */
 585                         re_clear_display(el);   /* reset the display stuff */
 586                         ch_reset(el);   /* reset the input pointers */
 587                         read_clearmacros(&el->el_read->macros);
 588                         re_refresh(el); /* print the prompt again */
 589                         break;
 590
 591                 case CC_ERROR:
 592                 default:        /* functions we don't know about */
 593                         terminal_beep(el);
 594                         terminal__flush(el);
 595                         break;
 596                 }
 597                 el->el_state.argument = 1;
 598                 el->el_state.doingarg = 0;
 599                 el->el_chared.c_vcmd.action = NOP;
 600                 if (el->el_flags & UNBUFFERED)
 601                         break;
 602         }
 603
 604         terminal__flush(el);            /* flush any buffered output */
 605         /* make sure the tty is set up correctly */
 606         if ((el->el_flags & UNBUFFERED) == 0) {
 607                 read_finish(el);
 608                 *nread = num != -1 ? num : 0;
 609         } else
 610                 *nread = (int)(el->el_line.lastchar - el->el_line.buffer);
 611
 612         if (*nread == 0) {
 613                 if (num == -1) {
 614                         *nread = -1;
 615                         if (el->el_read->read_errno)
 616                                 errno = el->el_read->read_errno;
 617                 }
 618                 return NULL;
 619         } else
 620                 return el->el_line.buffer;
 621 }