contrib/libedit/src/read.c

   1 /*      $NetBSD: read.c,v 1.102 2016/12/11 15:47:06 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 1.102 2016/12/11 15:47:06 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         int num;
 233
 234         do {
 235                 if ((num = el_wgetc(el, ch)) != 1)
 236                         return -1;
 237
 238 #ifdef  KANJI
 239                 if ((*ch & meta)) {
 240                         el->el_state.metanext = 0;
 241                         cmd = CcViMap[' '];
 242                         break;
 243                 } else
 244 #endif /* KANJI */
 245
 246                 if (el->el_state.metanext) {
 247                         el->el_state.metanext = 0;
 248                         *ch |= meta;
 249                 }
 250                 if (*ch >= N_KEYS)
 251                         cmd = ED_INSERT;
 252                 else
 253                         cmd = el->el_map.current[(unsigned char) *ch];
 254                 if (cmd == ED_SEQUENCE_LEAD_IN) {
 255                         keymacro_value_t val;
 256                         switch (keymacro_get(el, ch, &val)) {
 257                         case XK_CMD:
 258                                 cmd = val.cmd;
 259                                 break;
 260                         case XK_STR:
 261                                 el_wpush(el, val.str);
 262                                 break;
 263                         case XK_NOD:
 264                                 return -1;
 265                         default:
 266                                 EL_ABORT((el->el_errfile, "Bad XK_ type \n"));
 267                                 break;
 268                         }
 269                 }
 270         } while (cmd == ED_SEQUENCE_LEAD_IN);
 271         *cmdnum = cmd;
 272         return 0;
 273 }
 274
 275 /* read_char():
 276  *      Read a character from the tty.
 277  */
 278 static int
 279 read_char(EditLine *el, wchar_t *cp)
 280 {
 281         ssize_t num_read;
 282         int tried = 0;
 283         char cbuf[MB_LEN_MAX];
 284         size_t cbp = 0;
 285         int save_errno = errno;
 286
 287  again:
 288         el->el_signal->sig_no = 0;
 289         while ((num_read = read(el->el_infd, cbuf + cbp, (size_t)1)) == -1) {
 290                 int e = errno;
 291                 switch (el->el_signal->sig_no) {
 292                 case SIGCONT:
 293                         el_wset(el, EL_REFRESH);
 294                         /*FALLTHROUGH*/
 295                 case SIGWINCH:
 296                         sig_set(el);
 297                         goto again;
 298                 default:
 299                         break;
 300                 }
 301                 if (!tried && read__fixio(el->el_infd, e) == 0) {
 302                         errno = save_errno;
 303                         tried = 1;
 304                 } else {
 305                         errno = e;
 306                         *cp = L'\0';
 307                         return -1;
 308                 }
 309         }
 310
 311         /* Test for EOF */
 312         if (num_read == 0) {
 313                 *cp = L'\0';
 314                 return 0;
 315         }
 316
 317         for (;;) {
 318                 mbstate_t mbs;
 319
 320                 ++cbp;
 321                 /* This only works because UTF8 is stateless. */
 322                 memset(&mbs, 0, sizeof(mbs));
 323                 switch (mbrtowc(cp, cbuf, cbp, &mbs)) {
 324                 case (size_t)-1:
 325                         if (cbp > 1) {
 326                                 /*
 327                                  * Invalid sequence, discard all bytes
 328                                  * except the last one.
 329                                  */
 330                                 cbuf[0] = cbuf[cbp - 1];
 331                                 cbp = 0;
 332                                 break;
 333                         } else {
 334                                 /* Invalid byte, discard it. */
 335                                 cbp = 0;
 336                                 goto again;
 337                         }
 338                 case (size_t)-2:
 339                         /*
 340                          * We don't support other multibyte charsets.
 341                          * The second condition shouldn't happen
 342                          * and is here merely for additional safety.
 343                          */
 344                         if ((el->el_flags & CHARSET_IS_UTF8) == 0 ||
 345                             cbp >= MB_LEN_MAX) {
 346                                 errno = EILSEQ;
 347                                 *cp = L'\0';
 348                                 return -1;
 349                         }
 350                         /* Incomplete sequence, read another byte. */
 351                         goto again;
 352                 default:
 353                         /* Valid character, process it. */
 354                         return 1;
 355                 }
 356         }
 357 }
 358
 359 /* read_pop():
 360  *      Pop a macro from the stack
 361  */
 362 static void
 363 read_pop(struct macros *ma)
 364 {
 365         int i;
 366
 367         el_free(ma->macro[0]);
 368         for (i = 0; i < ma->level; i++)
 369                 ma->macro[i] = ma->macro[i + 1];
 370         ma->level--;
 371         ma->offset = 0;
 372 }
 373
 374 static void
 375 read_clearmacros(struct macros *ma)
 376 {
 377         while (ma->level >= 0)
 378                 el_free(ma->macro[ma->level--]);
 379         ma->offset = 0;
 380 }
 381
 382 /* el_wgetc():
 383  *      Read a wide character
 384  */
 385 int
 386 el_wgetc(EditLine *el, wchar_t *cp)
 387 {
 388         struct macros *ma = &el->el_read->macros;
 389         int num_read;
 390
 391         terminal__flush(el);
 392         for (;;) {
 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         if (tty_rawmode(el) < 0)/* make sure the tty is set up correctly */
 412                 return 0;
 413
 414         num_read = (*el->el_read->read_char)(el, cp);
 415
 416         /*
 417          * Remember the original reason of a read failure
 418          * such that el_wgets() can restore it after doing
 419          * various cleanup operation that might change errno.
 420          */
 421         if (num_read < 0)
 422                 el->el_read->read_errno = errno;
 423
 424         return num_read;
 425 }
 426
 427 libedit_private void
 428 read_prepare(EditLine *el)
 429 {
 430         if (el->el_flags & HANDLE_SIGNALS)
 431                 sig_set(el);
 432         if (el->el_flags & NO_TTY)
 433                 return;
 434         if ((el->el_flags & (UNBUFFERED|EDIT_DISABLED)) == UNBUFFERED)
 435                 tty_rawmode(el);
 436
 437         /* This is relatively cheap, and things go terribly wrong if
 438            we have the wrong size. */
 439         el_resize(el);
 440         re_clear_display(el);   /* reset the display stuff */
 441         ch_reset(el);
 442         re_refresh(el);         /* print the prompt */
 443
 444         if (el->el_flags & UNBUFFERED)
 445                 terminal__flush(el);
 446 }
 447
 448 libedit_private void
 449 read_finish(EditLine *el)
 450 {
 451         if ((el->el_flags & UNBUFFERED) == 0)
 452                 (void) tty_cookedmode(el);
 453         if (el->el_flags & HANDLE_SIGNALS)
 454                 sig_clr(el);
 455 }
 456
 457 static const wchar_t *
 458 noedit_wgets(EditLine *el, int *nread)
 459 {
 460         el_line_t       *lp = &el->el_line;
 461         int              num;
 462
 463         while ((num = (*el->el_read->read_char)(el, lp->lastchar)) == 1) {
 464                 if (lp->lastchar + 1 >= lp->limit &&
 465                     !ch_enlargebufs(el, (size_t)2))
 466                         break;
 467                 lp->lastchar++;
 468                 if (el->el_flags & UNBUFFERED ||
 469                     lp->lastchar[-1] == '\r' ||
 470                     lp->lastchar[-1] == '\n')
 471                         break;
 472         }
 473         if (num == -1 && errno == EINTR)
 474                 lp->lastchar = lp->buffer;
 475         lp->cursor = lp->lastchar;
 476         *lp->lastchar = '\0';
 477         *nread = (int)(lp->lastchar - lp->buffer);
 478         return *nread ? lp->buffer : NULL;
 479 }
 480
 481 const wchar_t *
 482 el_wgets(EditLine *el, int *nread)
 483 {
 484         int retval;
 485         el_action_t cmdnum = 0;
 486         int num;                /* how many chars we have read at NL */
 487         wchar_t ch;
 488         int nrb;
 489
 490         if (nread == NULL)
 491                 nread = &nrb;
 492         *nread = 0;
 493         el->el_read->read_errno = 0;
 494
 495         if (el->el_flags & NO_TTY) {
 496                 el->el_line.lastchar = el->el_line.buffer;
 497                 return noedit_wgets(el, nread);
 498         }
 499
 500 #ifdef FIONREAD
 501         if (el->el_tty.t_mode == EX_IO && el->el_read->macros.level < 0) {
 502                 int chrs = 0;
 503
 504                 (void) ioctl(el->el_infd, FIONREAD, &chrs);
 505                 if (chrs == 0) {
 506                         if (tty_rawmode(el) < 0) {
 507                                 errno = 0;
 508                                 *nread = 0;
 509                                 return NULL;
 510                         }
 511                 }
 512         }
 513 #endif /* FIONREAD */
 514
 515         if ((el->el_flags & UNBUFFERED) == 0)
 516                 read_prepare(el);
 517
 518         if (el->el_flags & EDIT_DISABLED) {
 519                 if ((el->el_flags & UNBUFFERED) == 0)
 520                         el->el_line.lastchar = el->el_line.buffer;
 521                 terminal__flush(el);
 522                 return noedit_wgets(el, nread);
 523         }
 524
 525         for (num = -1; num == -1;) {  /* while still editing this line */
 526                 /* if EOF or error */
 527                 if (read_getcmd(el, &cmdnum, &ch) == -1)
 528                         break;
 529                 if ((size_t)cmdnum >= el->el_map.nfunc) /* BUG CHECK command */
 530                         continue;       /* try again */
 531                 /* now do the real command */
 532                 /* vi redo needs these way down the levels... */
 533                 el->el_state.thiscmd = cmdnum;
 534                 el->el_state.thisch = ch;
 535                 if (el->el_map.type == MAP_VI &&
 536                     el->el_map.current == el->el_map.key &&
 537                     el->el_chared.c_redo.pos < el->el_chared.c_redo.lim) {
 538                         if (cmdnum == VI_DELETE_PREV_CHAR &&
 539                             el->el_chared.c_redo.pos != el->el_chared.c_redo.buf
 540                             && iswprint(el->el_chared.c_redo.pos[-1]))
 541                                 el->el_chared.c_redo.pos--;
 542                         else
 543                                 *el->el_chared.c_redo.pos++ = ch;
 544                 }
 545                 retval = (*el->el_map.func[cmdnum]) (el, ch);
 546
 547                 /* save the last command here */
 548                 el->el_state.lastcmd = cmdnum;
 549
 550                 /* use any return value */
 551                 switch (retval) {
 552                 case CC_CURSOR:
 553                         re_refresh_cursor(el);
 554                         break;
 555
 556                 case CC_REDISPLAY:
 557                         re_clear_lines(el);
 558                         re_clear_display(el);
 559                         /* FALLTHROUGH */
 560
 561                 case CC_REFRESH:
 562                         re_refresh(el);
 563                         break;
 564
 565                 case CC_REFRESH_BEEP:
 566                         re_refresh(el);
 567                         terminal_beep(el);
 568                         break;
 569
 570                 case CC_NORM:   /* normal char */
 571                         break;
 572
 573                 case CC_ARGHACK:        /* Suggested by Rich Salz */
 574                         /* <rsalz@pineapple.bbn.com> */
 575                         continue;       /* keep going... */
 576
 577                 case CC_EOF:    /* end of file typed */
 578                         if ((el->el_flags & UNBUFFERED) == 0)
 579                                 num = 0;
 580                         else if (num == -1) {
 581                                 *el->el_line.lastchar++ = CONTROL('d');
 582                                 el->el_line.cursor = el->el_line.lastchar;
 583                                 num = 1;
 584                         }
 585                         break;
 586
 587                 case CC_NEWLINE:        /* normal end of line */
 588                         num = (int)(el->el_line.lastchar - el->el_line.buffer);
 589                         break;
 590
 591                 case CC_FATAL:  /* fatal error, reset to known state */
 592                         /* put (real) cursor in a known place */
 593                         re_clear_display(el);   /* reset the display stuff */
 594                         ch_reset(el);   /* reset the input pointers */
 595                         read_clearmacros(&el->el_read->macros);
 596                         re_refresh(el); /* print the prompt again */
 597                         break;
 598
 599                 case CC_ERROR:
 600                 default:        /* functions we don't know about */
 601                         terminal_beep(el);
 602                         terminal__flush(el);
 603                         break;
 604                 }
 605                 el->el_state.argument = 1;
 606                 el->el_state.doingarg = 0;
 607                 el->el_chared.c_vcmd.action = NOP;
 608                 if (el->el_flags & UNBUFFERED)
 609                         break;
 610         }
 611
 612         terminal__flush(el);            /* flush any buffered output */
 613         /* make sure the tty is set up correctly */
 614         if ((el->el_flags & UNBUFFERED) == 0) {
 615                 read_finish(el);
 616                 *nread = num != -1 ? num : 0;
 617         } else
 618                 *nread = (int)(el->el_line.lastchar - el->el_line.buffer);
 619
 620         if (*nread == 0) {
 621                 if (num == -1) {
 622                         *nread = -1;
 623                         if (el->el_read->read_errno)
 624                                 errno = el->el_read->read_errno;
 625                 }
 626                 return NULL;
 627         } else
 628                 return el->el_line.buffer;
 629 }