1 /*- 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Kenneth Almquist. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 4. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #ifndef lint 34 #if 0 35 static char sccsid[] = "@(#)parser.c 8.7 (Berkeley) 5/16/95"; 36 #endif 37 #endif /* not lint */ 38 #include <sys/cdefs.h> 39 __FBSDID("$FreeBSD$"); 40 41 #include <stdlib.h> 42 #include <unistd.h> 43 #include <stdio.h> 44 45 #include "shell.h" 46 #include "parser.h" 47 #include "nodes.h" 48 #include "expand.h" /* defines rmescapes() */ 49 #include "syntax.h" 50 #include "options.h" 51 #include "input.h" 52 #include "output.h" 53 #include "var.h" 54 #include "error.h" 55 #include "memalloc.h" 56 #include "mystring.h" 57 #include "alias.h" 58 #include "show.h" 59 #include "eval.h" 60 #ifndef NO_HISTORY 61 #include "myhistedit.h" 62 #endif 63 64 /* 65 * Shell command parser. 66 */ 67 68 #define EOFMARKLEN 79 69 #define PROMPTLEN 128 70 71 /* values returned by readtoken */ 72 #include "token.h" 73 74 75 76 struct heredoc { 77 struct heredoc *next; /* next here document in list */ 78 union node *here; /* redirection node */ 79 char *eofmark; /* string indicating end of input */ 80 int striptabs; /* if set, strip leading tabs */ 81 }; 82 83 struct parser_temp { 84 struct parser_temp *next; 85 void *data; 86 }; 87 88 89 static struct heredoc *heredoclist; /* list of here documents to read */ 90 static int doprompt; /* if set, prompt the user */ 91 static int needprompt; /* true if interactive and at start of line */ 92 static int lasttoken; /* last token read */ 93 MKINIT int tokpushback; /* last token pushed back */ 94 static char *wordtext; /* text of last word returned by readtoken */ 95 MKINIT int checkkwd; /* 1 == check for kwds, 2 == also eat newlines */ 96 static struct nodelist *backquotelist; 97 static union node *redirnode; 98 static struct heredoc *heredoc; 99 static int quoteflag; /* set if (part of) last token was quoted */ 100 static int startlinno; /* line # where last token started */ 101 static int funclinno; /* line # where the current function started */ 102 static struct parser_temp *parser_temp; 103 104 /* XXX When 'noaliases' is set to one, no alias expansion takes place. */ 105 static int noaliases = 0; 106 107 108 static union node *list(int); 109 static union node *andor(void); 110 static union node *pipeline(void); 111 static union node *command(void); 112 static union node *simplecmd(union node **, union node *); 113 static union node *makename(void); 114 static void parsefname(void); 115 static void parseheredoc(void); 116 static int peektoken(void); 117 static int readtoken(void); 118 static int xxreadtoken(void); 119 static int readtoken1(int, char const *, char *, int); 120 static int noexpand(char *); 121 static void synexpect(int) __dead2; 122 static void synerror(const char *) __dead2; 123 static void setprompt(int); 124 125 126 static void * 127 parser_temp_alloc(size_t len) 128 { 129 struct parser_temp *t; 130 131 INTOFF; 132 t = ckmalloc(sizeof(*t)); 133 t->data = NULL; 134 t->next = parser_temp; 135 parser_temp = t; 136 t->data = ckmalloc(len); 137 INTON; 138 return t->data; 139 } 140 141 142 static void * 143 parser_temp_realloc(void *ptr, size_t len) 144 { 145 struct parser_temp *t; 146 147 INTOFF; 148 t = parser_temp; 149 if (ptr != t->data) 150 error("bug: parser_temp_realloc misused"); 151 t->data = ckrealloc(t->data, len); 152 INTON; 153 return t->data; 154 } 155 156 157 static void 158 parser_temp_free_upto(void *ptr) 159 { 160 struct parser_temp *t; 161 int done = 0; 162 163 INTOFF; 164 while (parser_temp != NULL && !done) { 165 t = parser_temp; 166 parser_temp = t->next; 167 done = t->data == ptr; 168 ckfree(t->data); 169 ckfree(t); 170 } 171 INTON; 172 if (!done) 173 error("bug: parser_temp_free_upto misused"); 174 } 175 176 177 static void 178 parser_temp_free_all(void) 179 { 180 struct parser_temp *t; 181 182 INTOFF; 183 while (parser_temp != NULL) { 184 t = parser_temp; 185 parser_temp = t->next; 186 ckfree(t->data); 187 ckfree(t); 188 } 189 INTON; 190 } 191 192 193 /* 194 * Read and parse a command. Returns NEOF on end of file. (NULL is a 195 * valid parse tree indicating a blank line.) 196 */ 197 198 union node * 199 parsecmd(int interact) 200 { 201 int t; 202 203 /* This assumes the parser is not re-entered, 204 * which could happen if we add command substitution on PS1/PS2. 205 */ 206 parser_temp_free_all(); 207 heredoclist = NULL; 208 209 tokpushback = 0; 210 doprompt = interact; 211 if (doprompt) 212 setprompt(1); 213 else 214 setprompt(0); 215 needprompt = 0; 216 t = readtoken(); 217 if (t == TEOF) 218 return NEOF; 219 if (t == TNL) 220 return NULL; 221 tokpushback++; 222 return list(1); 223 } 224 225 226 static union node * 227 list(int nlflag) 228 { 229 union node *n1, *n2, *n3; 230 int tok; 231 232 checkkwd = 2; 233 if (nlflag == 0 && tokendlist[peektoken()]) 234 return NULL; 235 n1 = NULL; 236 for (;;) { 237 n2 = andor(); 238 tok = readtoken(); 239 if (tok == TBACKGND) { 240 if (n2->type == NCMD || n2->type == NPIPE) { 241 n2->ncmd.backgnd = 1; 242 } else if (n2->type == NREDIR) { 243 n2->type = NBACKGND; 244 } else { 245 n3 = (union node *)stalloc(sizeof (struct nredir)); 246 n3->type = NBACKGND; 247 n3->nredir.n = n2; 248 n3->nredir.redirect = NULL; 249 n2 = n3; 250 } 251 } 252 if (n1 == NULL) { 253 n1 = n2; 254 } 255 else { 256 n3 = (union node *)stalloc(sizeof (struct nbinary)); 257 n3->type = NSEMI; 258 n3->nbinary.ch1 = n1; 259 n3->nbinary.ch2 = n2; 260 n1 = n3; 261 } 262 switch (tok) { 263 case TBACKGND: 264 case TSEMI: 265 tok = readtoken(); 266 /* FALLTHROUGH */ 267 case TNL: 268 if (tok == TNL) { 269 parseheredoc(); 270 if (nlflag) 271 return n1; 272 } else if (tok == TEOF && nlflag) { 273 parseheredoc(); 274 return n1; 275 } else { 276 tokpushback++; 277 } 278 checkkwd = 2; 279 if (tokendlist[peektoken()]) 280 return n1; 281 break; 282 case TEOF: 283 if (heredoclist) 284 parseheredoc(); 285 else 286 pungetc(); /* push back EOF on input */ 287 return n1; 288 default: 289 if (nlflag) 290 synexpect(-1); 291 tokpushback++; 292 return n1; 293 } 294 } 295 } 296 297 298 299 static union node * 300 andor(void) 301 { 302 union node *n1, *n2, *n3; 303 int t; 304 305 n1 = pipeline(); 306 for (;;) { 307 if ((t = readtoken()) == TAND) { 308 t = NAND; 309 } else if (t == TOR) { 310 t = NOR; 311 } else { 312 tokpushback++; 313 return n1; 314 } 315 n2 = pipeline(); 316 n3 = (union node *)stalloc(sizeof (struct nbinary)); 317 n3->type = t; 318 n3->nbinary.ch1 = n1; 319 n3->nbinary.ch2 = n2; 320 n1 = n3; 321 } 322 } 323 324 325 326 static union node * 327 pipeline(void) 328 { 329 union node *n1, *n2, *pipenode; 330 struct nodelist *lp, *prev; 331 int negate; 332 333 negate = 0; 334 checkkwd = 2; 335 TRACE(("pipeline: entered\n")); 336 while (readtoken() == TNOT) 337 negate = !negate; 338 tokpushback++; 339 n1 = command(); 340 if (readtoken() == TPIPE) { 341 pipenode = (union node *)stalloc(sizeof (struct npipe)); 342 pipenode->type = NPIPE; 343 pipenode->npipe.backgnd = 0; 344 lp = (struct nodelist *)stalloc(sizeof (struct nodelist)); 345 pipenode->npipe.cmdlist = lp; 346 lp->n = n1; 347 do { 348 prev = lp; 349 lp = (struct nodelist *)stalloc(sizeof (struct nodelist)); 350 lp->n = command(); 351 prev->next = lp; 352 } while (readtoken() == TPIPE); 353 lp->next = NULL; 354 n1 = pipenode; 355 } 356 tokpushback++; 357 if (negate) { 358 n2 = (union node *)stalloc(sizeof (struct nnot)); 359 n2->type = NNOT; 360 n2->nnot.com = n1; 361 return n2; 362 } else 363 return n1; 364 } 365 366 367 368 static union node * 369 command(void) 370 { 371 union node *n1, *n2; 372 union node *ap, **app; 373 union node *cp, **cpp; 374 union node *redir, **rpp; 375 int t, negate = 0; 376 377 checkkwd = 2; 378 redir = NULL; 379 n1 = NULL; 380 rpp = &redir; 381 382 /* Check for redirection which may precede command */ 383 while (readtoken() == TREDIR) { 384 *rpp = n2 = redirnode; 385 rpp = &n2->nfile.next; 386 parsefname(); 387 } 388 tokpushback++; 389 390 while (readtoken() == TNOT) { 391 TRACE(("command: TNOT recognized\n")); 392 negate = !negate; 393 } 394 tokpushback++; 395 396 switch (readtoken()) { 397 case TIF: 398 n1 = (union node *)stalloc(sizeof (struct nif)); 399 n1->type = NIF; 400 if ((n1->nif.test = list(0)) == NULL) 401 synexpect(-1); 402 if (readtoken() != TTHEN) 403 synexpect(TTHEN); 404 n1->nif.ifpart = list(0); 405 n2 = n1; 406 while (readtoken() == TELIF) { 407 n2->nif.elsepart = (union node *)stalloc(sizeof (struct nif)); 408 n2 = n2->nif.elsepart; 409 n2->type = NIF; 410 if ((n2->nif.test = list(0)) == NULL) 411 synexpect(-1); 412 if (readtoken() != TTHEN) 413 synexpect(TTHEN); 414 n2->nif.ifpart = list(0); 415 } 416 if (lasttoken == TELSE) 417 n2->nif.elsepart = list(0); 418 else { 419 n2->nif.elsepart = NULL; 420 tokpushback++; 421 } 422 if (readtoken() != TFI) 423 synexpect(TFI); 424 checkkwd = 1; 425 break; 426 case TWHILE: 427 case TUNTIL: { 428 int got; 429 n1 = (union node *)stalloc(sizeof (struct nbinary)); 430 n1->type = (lasttoken == TWHILE)? NWHILE : NUNTIL; 431 if ((n1->nbinary.ch1 = list(0)) == NULL) 432 synexpect(-1); 433 if ((got=readtoken()) != TDO) { 434 TRACE(("expecting DO got %s %s\n", tokname[got], got == TWORD ? wordtext : "")); 435 synexpect(TDO); 436 } 437 n1->nbinary.ch2 = list(0); 438 if (readtoken() != TDONE) 439 synexpect(TDONE); 440 checkkwd = 1; 441 break; 442 } 443 case TFOR: 444 if (readtoken() != TWORD || quoteflag || ! goodname(wordtext)) 445 synerror("Bad for loop variable"); 446 n1 = (union node *)stalloc(sizeof (struct nfor)); 447 n1->type = NFOR; 448 n1->nfor.var = wordtext; 449 while (readtoken() == TNL) 450 ; 451 if (lasttoken == TWORD && ! quoteflag && equal(wordtext, "in")) { 452 app = ≈ 453 while (readtoken() == TWORD) { 454 n2 = (union node *)stalloc(sizeof (struct narg)); 455 n2->type = NARG; 456 n2->narg.text = wordtext; 457 n2->narg.backquote = backquotelist; 458 *app = n2; 459 app = &n2->narg.next; 460 } 461 *app = NULL; 462 n1->nfor.args = ap; 463 if (lasttoken != TNL && lasttoken != TSEMI) 464 synexpect(-1); 465 } else { 466 static char argvars[5] = { 467 CTLVAR, VSNORMAL|VSQUOTE, '@', '=', '\0' 468 }; 469 n2 = (union node *)stalloc(sizeof (struct narg)); 470 n2->type = NARG; 471 n2->narg.text = argvars; 472 n2->narg.backquote = NULL; 473 n2->narg.next = NULL; 474 n1->nfor.args = n2; 475 /* 476 * Newline or semicolon here is optional (but note 477 * that the original Bourne shell only allowed NL). 478 */ 479 if (lasttoken != TNL && lasttoken != TSEMI) 480 tokpushback++; 481 } 482 checkkwd = 2; 483 if ((t = readtoken()) == TDO) 484 t = TDONE; 485 else if (t == TBEGIN) 486 t = TEND; 487 else 488 synexpect(-1); 489 n1->nfor.body = list(0); 490 if (readtoken() != t) 491 synexpect(t); 492 checkkwd = 1; 493 break; 494 case TCASE: 495 n1 = (union node *)stalloc(sizeof (struct ncase)); 496 n1->type = NCASE; 497 if (readtoken() != TWORD) 498 synexpect(TWORD); 499 n1->ncase.expr = n2 = (union node *)stalloc(sizeof (struct narg)); 500 n2->type = NARG; 501 n2->narg.text = wordtext; 502 n2->narg.backquote = backquotelist; 503 n2->narg.next = NULL; 504 while (readtoken() == TNL); 505 if (lasttoken != TWORD || ! equal(wordtext, "in")) 506 synerror("expecting \"in\""); 507 cpp = &n1->ncase.cases; 508 noaliases = 1; /* turn off alias expansion */ 509 checkkwd = 2, readtoken(); 510 while (lasttoken != TESAC) { 511 *cpp = cp = (union node *)stalloc(sizeof (struct nclist)); 512 cp->type = NCLIST; 513 app = &cp->nclist.pattern; 514 if (lasttoken == TLP) 515 readtoken(); 516 for (;;) { 517 *app = ap = (union node *)stalloc(sizeof (struct narg)); 518 ap->type = NARG; 519 ap->narg.text = wordtext; 520 ap->narg.backquote = backquotelist; 521 if (checkkwd = 2, readtoken() != TPIPE) 522 break; 523 app = &ap->narg.next; 524 readtoken(); 525 } 526 ap->narg.next = NULL; 527 if (lasttoken != TRP) 528 noaliases = 0, synexpect(TRP); 529 cp->nclist.body = list(0); 530 531 checkkwd = 2; 532 if ((t = readtoken()) != TESAC) { 533 if (t != TENDCASE) 534 noaliases = 0, synexpect(TENDCASE); 535 else 536 checkkwd = 2, readtoken(); 537 } 538 cpp = &cp->nclist.next; 539 } 540 noaliases = 0; /* reset alias expansion */ 541 *cpp = NULL; 542 checkkwd = 1; 543 break; 544 case TLP: 545 n1 = (union node *)stalloc(sizeof (struct nredir)); 546 n1->type = NSUBSHELL; 547 n1->nredir.n = list(0); 548 n1->nredir.redirect = NULL; 549 if (readtoken() != TRP) 550 synexpect(TRP); 551 checkkwd = 1; 552 break; 553 case TBEGIN: 554 n1 = list(0); 555 if (readtoken() != TEND) 556 synexpect(TEND); 557 checkkwd = 1; 558 break; 559 /* Handle an empty command like other simple commands. */ 560 case TBACKGND: 561 case TSEMI: 562 case TAND: 563 case TOR: 564 /* 565 * An empty command before a ; doesn't make much sense, and 566 * should certainly be disallowed in the case of `if ;'. 567 */ 568 if (!redir) 569 synexpect(-1); 570 case TNL: 571 case TEOF: 572 case TWORD: 573 case TRP: 574 tokpushback++; 575 n1 = simplecmd(rpp, redir); 576 goto checkneg; 577 default: 578 synexpect(-1); 579 } 580 581 /* Now check for redirection which may follow command */ 582 while (readtoken() == TREDIR) { 583 *rpp = n2 = redirnode; 584 rpp = &n2->nfile.next; 585 parsefname(); 586 } 587 tokpushback++; 588 *rpp = NULL; 589 if (redir) { 590 if (n1->type != NSUBSHELL) { 591 n2 = (union node *)stalloc(sizeof (struct nredir)); 592 n2->type = NREDIR; 593 n2->nredir.n = n1; 594 n1 = n2; 595 } 596 n1->nredir.redirect = redir; 597 } 598 599 checkneg: 600 if (negate) { 601 n2 = (union node *)stalloc(sizeof (struct nnot)); 602 n2->type = NNOT; 603 n2->nnot.com = n1; 604 return n2; 605 } 606 else 607 return n1; 608 } 609 610 611 static union node * 612 simplecmd(union node **rpp, union node *redir) 613 { 614 union node *args, **app; 615 union node **orig_rpp = rpp; 616 union node *n = NULL; 617 618 /* If we don't have any redirections already, then we must reset */ 619 /* rpp to be the address of the local redir variable. */ 620 if (redir == 0) 621 rpp = &redir; 622 623 args = NULL; 624 app = &args; 625 /* 626 * We save the incoming value, because we need this for shell 627 * functions. There can not be a redirect or an argument between 628 * the function name and the open parenthesis. 629 */ 630 orig_rpp = rpp; 631 632 for (;;) { 633 if (readtoken() == TWORD) { 634 n = (union node *)stalloc(sizeof (struct narg)); 635 n->type = NARG; 636 n->narg.text = wordtext; 637 n->narg.backquote = backquotelist; 638 *app = n; 639 app = &n->narg.next; 640 } else if (lasttoken == TREDIR) { 641 *rpp = n = redirnode; 642 rpp = &n->nfile.next; 643 parsefname(); /* read name of redirection file */ 644 } else if (lasttoken == TLP && app == &args->narg.next 645 && rpp == orig_rpp) { 646 /* We have a function */ 647 if (readtoken() != TRP) 648 synexpect(TRP); 649 funclinno = plinno; 650 #ifdef notdef 651 if (! goodname(n->narg.text)) 652 synerror("Bad function name"); 653 #endif 654 n->type = NDEFUN; 655 n->narg.next = command(); 656 funclinno = 0; 657 return n; 658 } else { 659 tokpushback++; 660 break; 661 } 662 } 663 *app = NULL; 664 *rpp = NULL; 665 n = (union node *)stalloc(sizeof (struct ncmd)); 666 n->type = NCMD; 667 n->ncmd.backgnd = 0; 668 n->ncmd.args = args; 669 n->ncmd.redirect = redir; 670 return n; 671 } 672 673 static union node * 674 makename(void) 675 { 676 union node *n; 677 678 n = (union node *)stalloc(sizeof (struct narg)); 679 n->type = NARG; 680 n->narg.next = NULL; 681 n->narg.text = wordtext; 682 n->narg.backquote = backquotelist; 683 return n; 684 } 685 686 void 687 fixredir(union node *n, const char *text, int err) 688 { 689 TRACE(("Fix redir %s %d\n", text, err)); 690 if (!err) 691 n->ndup.vname = NULL; 692 693 if (is_digit(text[0]) && text[1] == '\0') 694 n->ndup.dupfd = digit_val(text[0]); 695 else if (text[0] == '-' && text[1] == '\0') 696 n->ndup.dupfd = -1; 697 else { 698 699 if (err) 700 synerror("Bad fd number"); 701 else 702 n->ndup.vname = makename(); 703 } 704 } 705 706 707 static void 708 parsefname(void) 709 { 710 union node *n = redirnode; 711 712 if (readtoken() != TWORD) 713 synexpect(-1); 714 if (n->type == NHERE) { 715 struct heredoc *here = heredoc; 716 struct heredoc *p; 717 int i; 718 719 if (quoteflag == 0) 720 n->type = NXHERE; 721 TRACE(("Here document %d\n", n->type)); 722 if (here->striptabs) { 723 while (*wordtext == '\t') 724 wordtext++; 725 } 726 if (! noexpand(wordtext) || (i = strlen(wordtext)) == 0 || i > EOFMARKLEN) 727 synerror("Illegal eof marker for << redirection"); 728 rmescapes(wordtext); 729 here->eofmark = wordtext; 730 here->next = NULL; 731 if (heredoclist == NULL) 732 heredoclist = here; 733 else { 734 for (p = heredoclist ; p->next ; p = p->next); 735 p->next = here; 736 } 737 } else if (n->type == NTOFD || n->type == NFROMFD) { 738 fixredir(n, wordtext, 0); 739 } else { 740 n->nfile.fname = makename(); 741 } 742 } 743 744 745 /* 746 * Input any here documents. 747 */ 748 749 static void 750 parseheredoc(void) 751 { 752 struct heredoc *here; 753 union node *n; 754 755 while (heredoclist) { 756 here = heredoclist; 757 heredoclist = here->next; 758 if (needprompt) { 759 setprompt(2); 760 needprompt = 0; 761 } 762 readtoken1(pgetc(), here->here->type == NHERE? SQSYNTAX : DQSYNTAX, 763 here->eofmark, here->striptabs); 764 n = (union node *)stalloc(sizeof (struct narg)); 765 n->narg.type = NARG; 766 n->narg.next = NULL; 767 n->narg.text = wordtext; 768 n->narg.backquote = backquotelist; 769 here->here->nhere.doc = n; 770 } 771 } 772 773 static int 774 peektoken(void) 775 { 776 int t; 777 778 t = readtoken(); 779 tokpushback++; 780 return (t); 781 } 782 783 static int 784 readtoken(void) 785 { 786 int t; 787 int savecheckkwd = checkkwd; 788 struct alias *ap; 789 #ifdef DEBUG 790 int alreadyseen = tokpushback; 791 #endif 792 793 top: 794 t = xxreadtoken(); 795 796 if (checkkwd) { 797 /* 798 * eat newlines 799 */ 800 if (checkkwd == 2) { 801 checkkwd = 0; 802 while (t == TNL) { 803 parseheredoc(); 804 t = xxreadtoken(); 805 } 806 } else 807 checkkwd = 0; 808 /* 809 * check for keywords and aliases 810 */ 811 if (t == TWORD && !quoteflag) 812 { 813 const char * const *pp; 814 815 for (pp = parsekwd; *pp; pp++) { 816 if (**pp == *wordtext && equal(*pp, wordtext)) 817 { 818 lasttoken = t = pp - parsekwd + KWDOFFSET; 819 TRACE(("keyword %s recognized\n", tokname[t])); 820 goto out; 821 } 822 } 823 if (noaliases == 0 && 824 (ap = lookupalias(wordtext, 1)) != NULL) { 825 pushstring(ap->val, strlen(ap->val), ap); 826 checkkwd = savecheckkwd; 827 goto top; 828 } 829 } 830 out: 831 checkkwd = (t == TNOT) ? savecheckkwd : 0; 832 } 833 #ifdef DEBUG 834 if (!alreadyseen) 835 TRACE(("token %s %s\n", tokname[t], t == TWORD ? wordtext : "")); 836 else 837 TRACE(("reread token %s %s\n", tokname[t], t == TWORD ? wordtext : "")); 838 #endif 839 return (t); 840 } 841 842 843 /* 844 * Read the next input token. 845 * If the token is a word, we set backquotelist to the list of cmds in 846 * backquotes. We set quoteflag to true if any part of the word was 847 * quoted. 848 * If the token is TREDIR, then we set redirnode to a structure containing 849 * the redirection. 850 * In all cases, the variable startlinno is set to the number of the line 851 * on which the token starts. 852 * 853 * [Change comment: here documents and internal procedures] 854 * [Readtoken shouldn't have any arguments. Perhaps we should make the 855 * word parsing code into a separate routine. In this case, readtoken 856 * doesn't need to have any internal procedures, but parseword does. 857 * We could also make parseoperator in essence the main routine, and 858 * have parseword (readtoken1?) handle both words and redirection.] 859 */ 860 861 #define RETURN(token) return lasttoken = token 862 863 static int 864 xxreadtoken(void) 865 { 866 int c; 867 868 if (tokpushback) { 869 tokpushback = 0; 870 return lasttoken; 871 } 872 if (needprompt) { 873 setprompt(2); 874 needprompt = 0; 875 } 876 startlinno = plinno; 877 for (;;) { /* until token or start of word found */ 878 c = pgetc_macro(); 879 if (c == ' ' || c == '\t') 880 continue; /* quick check for white space first */ 881 switch (c) { 882 case ' ': case '\t': 883 continue; 884 case '#': 885 while ((c = pgetc()) != '\n' && c != PEOF); 886 pungetc(); 887 continue; 888 case '\\': 889 if (pgetc() == '\n') { 890 startlinno = ++plinno; 891 if (doprompt) 892 setprompt(2); 893 else 894 setprompt(0); 895 continue; 896 } 897 pungetc(); 898 goto breakloop; 899 case '\n': 900 plinno++; 901 needprompt = doprompt; 902 RETURN(TNL); 903 case PEOF: 904 RETURN(TEOF); 905 case '&': 906 if (pgetc() == '&') 907 RETURN(TAND); 908 pungetc(); 909 RETURN(TBACKGND); 910 case '|': 911 if (pgetc() == '|') 912 RETURN(TOR); 913 pungetc(); 914 RETURN(TPIPE); 915 case ';': 916 if (pgetc() == ';') 917 RETURN(TENDCASE); 918 pungetc(); 919 RETURN(TSEMI); 920 case '(': 921 RETURN(TLP); 922 case ')': 923 RETURN(TRP); 924 default: 925 goto breakloop; 926 } 927 } 928 breakloop: 929 return readtoken1(c, BASESYNTAX, (char *)NULL, 0); 930 #undef RETURN 931 } 932 933 934 #define MAXNEST_static 8 935 struct tokenstate 936 { 937 const char *syntax; /* *SYNTAX */ 938 int parenlevel; /* levels of parentheses in arithmetic */ 939 enum tokenstate_category 940 { 941 TSTATE_TOP, 942 TSTATE_VAR_OLD, /* ${var+-=?}, inherits dquotes */ 943 TSTATE_VAR_NEW, /* other ${var...}, own dquote state */ 944 TSTATE_ARITH 945 } category; 946 }; 947 948 949 /* 950 * Called to parse command substitutions. 951 */ 952 953 static char * 954 parsebackq(char *out, struct nodelist **pbqlist, 955 int oldstyle, int dblquote, int quoted) 956 { 957 struct nodelist **nlpp; 958 union node *n; 959 char *volatile str; 960 struct jmploc jmploc; 961 struct jmploc *const savehandler = handler; 962 int savelen; 963 int saveprompt; 964 const int bq_startlinno = plinno; 965 char *volatile ostr = NULL; 966 struct parsefile *const savetopfile = getcurrentfile(); 967 struct heredoc *const saveheredoclist = heredoclist; 968 struct heredoc *here; 969 970 str = NULL; 971 if (setjmp(jmploc.loc)) { 972 popfilesupto(savetopfile); 973 if (str) 974 ckfree(str); 975 if (ostr) 976 ckfree(ostr); 977 heredoclist = saveheredoclist; 978 handler = savehandler; 979 if (exception == EXERROR) { 980 startlinno = bq_startlinno; 981 synerror("Error in command substitution"); 982 } 983 longjmp(handler->loc, 1); 984 } 985 INTOFF; 986 savelen = out - stackblock(); 987 if (savelen > 0) { 988 str = ckmalloc(savelen); 989 memcpy(str, stackblock(), savelen); 990 } 991 handler = &jmploc; 992 heredoclist = NULL; 993 INTON; 994 if (oldstyle) { 995 /* We must read until the closing backquote, giving special 996 treatment to some slashes, and then push the string and 997 reread it as input, interpreting it normally. */ 998 char *oout; 999 int c; 1000 int olen; 1001 1002 1003 STARTSTACKSTR(oout); 1004 for (;;) { 1005 if (needprompt) { 1006 setprompt(2); 1007 needprompt = 0; 1008 } 1009 switch (c = pgetc()) { 1010 case '`': 1011 goto done; 1012 1013 case '\\': 1014 if ((c = pgetc()) == '\n') { 1015 plinno++; 1016 if (doprompt) 1017 setprompt(2); 1018 else 1019 setprompt(0); 1020 /* 1021 * If eating a newline, avoid putting 1022 * the newline into the new character 1023 * stream (via the STPUTC after the 1024 * switch). 1025 */ 1026 continue; 1027 } 1028 if (c != '\\' && c != '`' && c != '$' 1029 && (!dblquote || c != '"')) 1030 STPUTC('\\', oout); 1031 break; 1032 1033 case '\n': 1034 plinno++; 1035 needprompt = doprompt; 1036 break; 1037 1038 case PEOF: 1039 startlinno = plinno; 1040 synerror("EOF in backquote substitution"); 1041 break; 1042 1043 default: 1044 break; 1045 } 1046 STPUTC(c, oout); 1047 } 1048 done: 1049 STPUTC('\0', oout); 1050 olen = oout - stackblock(); 1051 INTOFF; 1052 ostr = ckmalloc(olen); 1053 memcpy(ostr, stackblock(), olen); 1054 setinputstring(ostr, 1); 1055 INTON; 1056 } 1057 nlpp = pbqlist; 1058 while (*nlpp) 1059 nlpp = &(*nlpp)->next; 1060 *nlpp = (struct nodelist *)stalloc(sizeof (struct nodelist)); 1061 (*nlpp)->next = NULL; 1062 1063 if (oldstyle) { 1064 saveprompt = doprompt; 1065 doprompt = 0; 1066 } 1067 1068 n = list(0); 1069 1070 if (oldstyle) 1071 doprompt = saveprompt; 1072 else { 1073 if (readtoken() != TRP) 1074 synexpect(TRP); 1075 } 1076 1077 (*nlpp)->n = n; 1078 if (oldstyle) { 1079 /* 1080 * Start reading from old file again, ignoring any pushed back 1081 * tokens left from the backquote parsing 1082 */ 1083 popfile(); 1084 tokpushback = 0; 1085 } 1086 while (stackblocksize() <= savelen) 1087 growstackblock(); 1088 STARTSTACKSTR(out); 1089 INTOFF; 1090 if (str) { 1091 memcpy(out, str, savelen); 1092 STADJUST(savelen, out); 1093 ckfree(str); 1094 str = NULL; 1095 } 1096 if (ostr) { 1097 ckfree(ostr); 1098 ostr = NULL; 1099 } 1100 here = saveheredoclist; 1101 if (here != NULL) { 1102 while (here->next != NULL) 1103 here = here->next; 1104 here->next = heredoclist; 1105 heredoclist = saveheredoclist; 1106 } 1107 handler = savehandler; 1108 INTON; 1109 if (quoted) 1110 USTPUTC(CTLBACKQ | CTLQUOTE, out); 1111 else 1112 USTPUTC(CTLBACKQ, out); 1113 return out; 1114 } 1115 1116 1117 /* 1118 * If eofmark is NULL, read a word or a redirection symbol. If eofmark 1119 * is not NULL, read a here document. In the latter case, eofmark is the 1120 * word which marks the end of the document and striptabs is true if 1121 * leading tabs should be stripped from the document. The argument firstc 1122 * is the first character of the input token or document. 1123 * 1124 * Because C does not have internal subroutines, I have simulated them 1125 * using goto's to implement the subroutine linkage. The following macros 1126 * will run code that appears at the end of readtoken1. 1127 */ 1128 1129 #define CHECKEND() {goto checkend; checkend_return:;} 1130 #define PARSEREDIR() {goto parseredir; parseredir_return:;} 1131 #define PARSESUB() {goto parsesub; parsesub_return:;} 1132 #define PARSEARITH() {goto parsearith; parsearith_return:;} 1133 1134 static int 1135 readtoken1(int firstc, char const *initialsyntax, char *eofmark, int striptabs) 1136 { 1137 int c = firstc; 1138 char *out; 1139 int len; 1140 char line[EOFMARKLEN + 1]; 1141 struct nodelist *bqlist; 1142 int quotef; 1143 int newvarnest; 1144 int level; 1145 int synentry; 1146 struct tokenstate state_static[MAXNEST_static]; 1147 int maxnest = MAXNEST_static; 1148 struct tokenstate *state = state_static; 1149 1150 startlinno = plinno; 1151 quotef = 0; 1152 bqlist = NULL; 1153 newvarnest = 0; 1154 level = 0; 1155 state[level].syntax = initialsyntax; 1156 state[level].parenlevel = 0; 1157 state[level].category = TSTATE_TOP; 1158 1159 STARTSTACKSTR(out); 1160 loop: { /* for each line, until end of word */ 1161 CHECKEND(); /* set c to PEOF if at end of here document */ 1162 for (;;) { /* until end of line or end of word */ 1163 CHECKSTRSPACE(3, out); /* permit 3 calls to USTPUTC */ 1164 1165 synentry = state[level].syntax[c]; 1166 1167 switch(synentry) { 1168 case CNL: /* '\n' */ 1169 if (state[level].syntax == BASESYNTAX) 1170 goto endword; /* exit outer loop */ 1171 USTPUTC(c, out); 1172 plinno++; 1173 if (doprompt) 1174 setprompt(2); 1175 else 1176 setprompt(0); 1177 c = pgetc(); 1178 goto loop; /* continue outer loop */ 1179 case CWORD: 1180 USTPUTC(c, out); 1181 break; 1182 case CCTL: 1183 if (eofmark == NULL || initialsyntax != SQSYNTAX) 1184 USTPUTC(CTLESC, out); 1185 USTPUTC(c, out); 1186 break; 1187 case CBACK: /* backslash */ 1188 c = pgetc(); 1189 if (c == PEOF) { 1190 USTPUTC('\\', out); 1191 pungetc(); 1192 } else if (c == '\n') { 1193 plinno++; 1194 if (doprompt) 1195 setprompt(2); 1196 else 1197 setprompt(0); 1198 } else { 1199 if (state[level].syntax == DQSYNTAX && 1200 c != '\\' && c != '`' && c != '$' && 1201 (c != '"' || (eofmark != NULL && 1202 newvarnest == 0)) && 1203 (c != '}' || state[level].category != TSTATE_VAR_OLD)) 1204 USTPUTC('\\', out); 1205 if (SQSYNTAX[c] == CCTL) 1206 USTPUTC(CTLESC, out); 1207 else if (eofmark == NULL || 1208 newvarnest > 0) 1209 USTPUTC(CTLQUOTEMARK, out); 1210 USTPUTC(c, out); 1211 quotef++; 1212 } 1213 break; 1214 case CSQUOTE: 1215 USTPUTC(CTLQUOTEMARK, out); 1216 state[level].syntax = SQSYNTAX; 1217 break; 1218 case CDQUOTE: 1219 USTPUTC(CTLQUOTEMARK, out); 1220 state[level].syntax = DQSYNTAX; 1221 break; 1222 case CENDQUOTE: 1223 if (eofmark != NULL && newvarnest == 0) 1224 USTPUTC(c, out); 1225 else { 1226 if (state[level].category == TSTATE_ARITH) 1227 state[level].syntax = ARISYNTAX; 1228 else 1229 state[level].syntax = BASESYNTAX; 1230 quotef++; 1231 } 1232 break; 1233 case CVAR: /* '$' */ 1234 PARSESUB(); /* parse substitution */ 1235 break; 1236 case CENDVAR: /* '}' */ 1237 if (level > 0 && 1238 (state[level].category == TSTATE_VAR_OLD || 1239 state[level].category == TSTATE_VAR_NEW)) { 1240 if (state[level].category == TSTATE_VAR_OLD) 1241 state[level - 1].syntax = state[level].syntax; 1242 else 1243 newvarnest--; 1244 level--; 1245 USTPUTC(CTLENDVAR, out); 1246 } else { 1247 USTPUTC(c, out); 1248 } 1249 break; 1250 case CLP: /* '(' in arithmetic */ 1251 state[level].parenlevel++; 1252 USTPUTC(c, out); 1253 break; 1254 case CRP: /* ')' in arithmetic */ 1255 if (state[level].parenlevel > 0) { 1256 USTPUTC(c, out); 1257 --state[level].parenlevel; 1258 } else { 1259 if (pgetc() == ')') { 1260 if (level > 0 && 1261 state[level].category == TSTATE_ARITH) { 1262 level--; 1263 USTPUTC(CTLENDARI, out); 1264 } else 1265 USTPUTC(')', out); 1266 } else { 1267 /* 1268 * unbalanced parens 1269 * (don't 2nd guess - no error) 1270 */ 1271 pungetc(); 1272 USTPUTC(')', out); 1273 } 1274 } 1275 break; 1276 case CBQUOTE: /* '`' */ 1277 out = parsebackq(out, &bqlist, 1, 1278 state[level].syntax == DQSYNTAX && 1279 (eofmark == NULL || newvarnest > 0), 1280 state[level].syntax == DQSYNTAX || state[level].syntax == ARISYNTAX); 1281 break; 1282 case CEOF: 1283 goto endword; /* exit outer loop */ 1284 default: 1285 if (level == 0) 1286 goto endword; /* exit outer loop */ 1287 USTPUTC(c, out); 1288 } 1289 c = pgetc_macro(); 1290 } 1291 } 1292 endword: 1293 if (state[level].syntax == ARISYNTAX) 1294 synerror("Missing '))'"); 1295 if (state[level].syntax != BASESYNTAX && eofmark == NULL) 1296 synerror("Unterminated quoted string"); 1297 if (state[level].category == TSTATE_VAR_OLD || 1298 state[level].category == TSTATE_VAR_NEW) { 1299 startlinno = plinno; 1300 synerror("Missing '}'"); 1301 } 1302 if (state != state_static) 1303 parser_temp_free_upto(state); 1304 USTPUTC('\0', out); 1305 len = out - stackblock(); 1306 out = stackblock(); 1307 if (eofmark == NULL) { 1308 if ((c == '>' || c == '<') 1309 && quotef == 0 1310 && len <= 2 1311 && (*out == '\0' || is_digit(*out))) { 1312 PARSEREDIR(); 1313 return lasttoken = TREDIR; 1314 } else { 1315 pungetc(); 1316 } 1317 } 1318 quoteflag = quotef; 1319 backquotelist = bqlist; 1320 grabstackblock(len); 1321 wordtext = out; 1322 return lasttoken = TWORD; 1323 /* end of readtoken routine */ 1324 1325 1326 /* 1327 * Check to see whether we are at the end of the here document. When this 1328 * is called, c is set to the first character of the next input line. If 1329 * we are at the end of the here document, this routine sets the c to PEOF. 1330 */ 1331 1332 checkend: { 1333 if (eofmark) { 1334 if (striptabs) { 1335 while (c == '\t') 1336 c = pgetc(); 1337 } 1338 if (c == *eofmark) { 1339 if (pfgets(line, sizeof line) != NULL) { 1340 char *p, *q; 1341 1342 p = line; 1343 for (q = eofmark + 1 ; *q && *p == *q ; p++, q++); 1344 if (*p == '\n' && *q == '\0') { 1345 c = PEOF; 1346 plinno++; 1347 needprompt = doprompt; 1348 } else { 1349 pushstring(line, strlen(line), NULL); 1350 } 1351 } 1352 } 1353 } 1354 goto checkend_return; 1355 } 1356 1357 1358 /* 1359 * Parse a redirection operator. The variable "out" points to a string 1360 * specifying the fd to be redirected. The variable "c" contains the 1361 * first character of the redirection operator. 1362 */ 1363 1364 parseredir: { 1365 char fd = *out; 1366 union node *np; 1367 1368 np = (union node *)stalloc(sizeof (struct nfile)); 1369 if (c == '>') { 1370 np->nfile.fd = 1; 1371 c = pgetc(); 1372 if (c == '>') 1373 np->type = NAPPEND; 1374 else if (c == '&') 1375 np->type = NTOFD; 1376 else if (c == '|') 1377 np->type = NCLOBBER; 1378 else { 1379 np->type = NTO; 1380 pungetc(); 1381 } 1382 } else { /* c == '<' */ 1383 np->nfile.fd = 0; 1384 c = pgetc(); 1385 if (c == '<') { 1386 if (sizeof (struct nfile) != sizeof (struct nhere)) { 1387 np = (union node *)stalloc(sizeof (struct nhere)); 1388 np->nfile.fd = 0; 1389 } 1390 np->type = NHERE; 1391 heredoc = (struct heredoc *)stalloc(sizeof (struct heredoc)); 1392 heredoc->here = np; 1393 if ((c = pgetc()) == '-') { 1394 heredoc->striptabs = 1; 1395 } else { 1396 heredoc->striptabs = 0; 1397 pungetc(); 1398 } 1399 } else if (c == '&') 1400 np->type = NFROMFD; 1401 else if (c == '>') 1402 np->type = NFROMTO; 1403 else { 1404 np->type = NFROM; 1405 pungetc(); 1406 } 1407 } 1408 if (fd != '\0') 1409 np->nfile.fd = digit_val(fd); 1410 redirnode = np; 1411 goto parseredir_return; 1412 } 1413 1414 1415 /* 1416 * Parse a substitution. At this point, we have read the dollar sign 1417 * and nothing else. 1418 */ 1419 1420 parsesub: { 1421 char buf[10]; 1422 int subtype; 1423 int typeloc; 1424 int flags; 1425 char *p; 1426 static const char types[] = "}-+?="; 1427 int bracketed_name = 0; /* used to handle ${[0-9]*} variables */ 1428 int i; 1429 int linno; 1430 int length; 1431 1432 c = pgetc(); 1433 if (c != '(' && c != '{' && (is_eof(c) || !is_name(c)) && 1434 !is_special(c)) { 1435 USTPUTC('$', out); 1436 pungetc(); 1437 } else if (c == '(') { /* $(command) or $((arith)) */ 1438 if (pgetc() == '(') { 1439 PARSEARITH(); 1440 } else { 1441 pungetc(); 1442 out = parsebackq(out, &bqlist, 0, 1443 state[level].syntax == DQSYNTAX && 1444 (eofmark == NULL || newvarnest > 0), 1445 state[level].syntax == DQSYNTAX || 1446 state[level].syntax == ARISYNTAX); 1447 } 1448 } else { 1449 USTPUTC(CTLVAR, out); 1450 typeloc = out - stackblock(); 1451 USTPUTC(VSNORMAL, out); 1452 subtype = VSNORMAL; 1453 flags = 0; 1454 if (c == '{') { 1455 bracketed_name = 1; 1456 c = pgetc(); 1457 if (c == '#') { 1458 if ((c = pgetc()) == '}') 1459 c = '#'; 1460 else 1461 subtype = VSLENGTH; 1462 } 1463 else 1464 subtype = 0; 1465 } 1466 if (!is_eof(c) && is_name(c)) { 1467 length = 0; 1468 do { 1469 STPUTC(c, out); 1470 c = pgetc(); 1471 length++; 1472 } while (!is_eof(c) && is_in_name(c)); 1473 if (length == 6 && 1474 strncmp(out - length, "LINENO", length) == 0) { 1475 /* Replace the variable name with the 1476 * current line number. */ 1477 linno = plinno; 1478 if (funclinno != 0) 1479 linno -= funclinno - 1; 1480 snprintf(buf, sizeof(buf), "%d", linno); 1481 STADJUST(-6, out); 1482 for (i = 0; buf[i] != '\0'; i++) 1483 STPUTC(buf[i], out); 1484 flags |= VSLINENO; 1485 } 1486 } else if (is_digit(c)) { 1487 if (bracketed_name) { 1488 do { 1489 STPUTC(c, out); 1490 c = pgetc(); 1491 } while (is_digit(c)); 1492 } else { 1493 STPUTC(c, out); 1494 c = pgetc(); 1495 } 1496 } else { 1497 if (! is_special(c)) { 1498 subtype = VSERROR; 1499 if (c == '}') 1500 pungetc(); 1501 else if (c == '\n' || c == PEOF) 1502 synerror("Unexpected end of line in substitution"); 1503 else 1504 USTPUTC(c, out); 1505 } else { 1506 USTPUTC(c, out); 1507 c = pgetc(); 1508 } 1509 } 1510 if (subtype == 0) { 1511 switch (c) { 1512 case ':': 1513 flags |= VSNUL; 1514 c = pgetc(); 1515 /*FALLTHROUGH*/ 1516 default: 1517 p = strchr(types, c); 1518 if (p == NULL) { 1519 if (c == '\n' || c == PEOF) 1520 synerror("Unexpected end of line in substitution"); 1521 if (flags == VSNUL) 1522 STPUTC(':', out); 1523 STPUTC(c, out); 1524 subtype = VSERROR; 1525 } else 1526 subtype = p - types + VSNORMAL; 1527 break; 1528 case '%': 1529 case '#': 1530 { 1531 int cc = c; 1532 subtype = c == '#' ? VSTRIMLEFT : 1533 VSTRIMRIGHT; 1534 c = pgetc(); 1535 if (c == cc) 1536 subtype++; 1537 else 1538 pungetc(); 1539 break; 1540 } 1541 } 1542 } else if (subtype != VSERROR) { 1543 pungetc(); 1544 } 1545 STPUTC('=', out); 1546 if (subtype != VSLENGTH && (state[level].syntax == DQSYNTAX || 1547 state[level].syntax == ARISYNTAX)) 1548 flags |= VSQUOTE; 1549 *(stackblock() + typeloc) = subtype | flags; 1550 if (subtype != VSNORMAL) { 1551 if (level + 1 >= maxnest) { 1552 maxnest *= 2; 1553 if (state == state_static) { 1554 state = parser_temp_alloc( 1555 maxnest * sizeof(*state)); 1556 memcpy(state, state_static, 1557 MAXNEST_static * sizeof(*state)); 1558 } else 1559 state = parser_temp_realloc(state, 1560 maxnest * sizeof(*state)); 1561 } 1562 level++; 1563 state[level].parenlevel = 0; 1564 if (subtype == VSMINUS || subtype == VSPLUS || 1565 subtype == VSQUESTION || subtype == VSASSIGN) { 1566 /* 1567 * For operators that were in the Bourne shell, 1568 * inherit the double-quote state. 1569 */ 1570 state[level].syntax = state[level - 1].syntax; 1571 state[level].category = TSTATE_VAR_OLD; 1572 } else { 1573 /* 1574 * The other operators take a pattern, 1575 * so go to BASESYNTAX. 1576 * Also, ' and " are now special, even 1577 * in here documents. 1578 */ 1579 state[level].syntax = BASESYNTAX; 1580 state[level].category = TSTATE_VAR_NEW; 1581 newvarnest++; 1582 } 1583 } 1584 } 1585 goto parsesub_return; 1586 } 1587 1588 1589 /* 1590 * Parse an arithmetic expansion (indicate start of one and set state) 1591 */ 1592 parsearith: { 1593 1594 if (level + 1 >= maxnest) { 1595 maxnest *= 2; 1596 if (state == state_static) { 1597 state = parser_temp_alloc( 1598 maxnest * sizeof(*state)); 1599 memcpy(state, state_static, 1600 MAXNEST_static * sizeof(*state)); 1601 } else 1602 state = parser_temp_realloc(state, 1603 maxnest * sizeof(*state)); 1604 } 1605 level++; 1606 state[level].syntax = ARISYNTAX; 1607 state[level].parenlevel = 0; 1608 state[level].category = TSTATE_ARITH; 1609 USTPUTC(CTLARI, out); 1610 if (state[level - 1].syntax == DQSYNTAX) 1611 USTPUTC('"',out); 1612 else 1613 USTPUTC(' ',out); 1614 goto parsearith_return; 1615 } 1616 1617 } /* end of readtoken */ 1618 1619 1620 1621 #ifdef mkinit 1622 RESET { 1623 tokpushback = 0; 1624 checkkwd = 0; 1625 } 1626 #endif 1627 1628 /* 1629 * Returns true if the text contains nothing to expand (no dollar signs 1630 * or backquotes). 1631 */ 1632 1633 static int 1634 noexpand(char *text) 1635 { 1636 char *p; 1637 char c; 1638 1639 p = text; 1640 while ((c = *p++) != '\0') { 1641 if ( c == CTLQUOTEMARK) 1642 continue; 1643 if (c == CTLESC) 1644 p++; 1645 else if (BASESYNTAX[(int)c] == CCTL) 1646 return 0; 1647 } 1648 return 1; 1649 } 1650 1651 1652 /* 1653 * Return true if the argument is a legal variable name (a letter or 1654 * underscore followed by zero or more letters, underscores, and digits). 1655 */ 1656 1657 int 1658 goodname(const char *name) 1659 { 1660 const char *p; 1661 1662 p = name; 1663 if (! is_name(*p)) 1664 return 0; 1665 while (*++p) { 1666 if (! is_in_name(*p)) 1667 return 0; 1668 } 1669 return 1; 1670 } 1671 1672 1673 /* 1674 * Called when an unexpected token is read during the parse. The argument 1675 * is the token that is expected, or -1 if more than one type of token can 1676 * occur at this point. 1677 */ 1678 1679 static void 1680 synexpect(int token) 1681 { 1682 char msg[64]; 1683 1684 if (token >= 0) { 1685 fmtstr(msg, 64, "%s unexpected (expecting %s)", 1686 tokname[lasttoken], tokname[token]); 1687 } else { 1688 fmtstr(msg, 64, "%s unexpected", tokname[lasttoken]); 1689 } 1690 synerror(msg); 1691 } 1692 1693 1694 static void 1695 synerror(const char *msg) 1696 { 1697 if (commandname) 1698 outfmt(out2, "%s: %d: ", commandname, startlinno); 1699 outfmt(out2, "Syntax error: %s\n", msg); 1700 error((char *)NULL); 1701 } 1702 1703 static void 1704 setprompt(int which) 1705 { 1706 whichprompt = which; 1707 1708 #ifndef NO_HISTORY 1709 if (!el) 1710 #endif 1711 { 1712 out2str(getprompt(NULL)); 1713 flushout(out2); 1714 } 1715 } 1716 1717 /* 1718 * called by editline -- any expansions to the prompt 1719 * should be added here. 1720 */ 1721 char * 1722 getprompt(void *unused __unused) 1723 { 1724 static char ps[PROMPTLEN]; 1725 char *fmt; 1726 const char *pwd; 1727 int i, trim; 1728 static char internal_error[] = "<internal prompt error>"; 1729 1730 /* 1731 * Select prompt format. 1732 */ 1733 switch (whichprompt) { 1734 case 0: 1735 fmt = nullstr; 1736 break; 1737 case 1: 1738 fmt = ps1val(); 1739 break; 1740 case 2: 1741 fmt = ps2val(); 1742 break; 1743 default: 1744 return internal_error; 1745 } 1746 1747 /* 1748 * Format prompt string. 1749 */ 1750 for (i = 0; (i < 127) && (*fmt != '\0'); i++, fmt++) 1751 if (*fmt == '\\') 1752 switch (*++fmt) { 1753 1754 /* 1755 * Hostname. 1756 * 1757 * \h specifies just the local hostname, 1758 * \H specifies fully-qualified hostname. 1759 */ 1760 case 'h': 1761 case 'H': 1762 ps[i] = '\0'; 1763 gethostname(&ps[i], PROMPTLEN - i); 1764 /* Skip to end of hostname. */ 1765 trim = (*fmt == 'h') ? '.' : '\0'; 1766 while ((ps[i+1] != '\0') && (ps[i+1] != trim)) 1767 i++; 1768 break; 1769 1770 /* 1771 * Working directory. 1772 * 1773 * \W specifies just the final component, 1774 * \w specifies the entire path. 1775 */ 1776 case 'W': 1777 case 'w': 1778 pwd = lookupvar("PWD"); 1779 if (pwd == NULL) 1780 pwd = "?"; 1781 if (*fmt == 'W' && 1782 *pwd == '/' && pwd[1] != '\0') 1783 strlcpy(&ps[i], strrchr(pwd, '/') + 1, 1784 PROMPTLEN - i); 1785 else 1786 strlcpy(&ps[i], pwd, PROMPTLEN - i); 1787 /* Skip to end of path. */ 1788 while (ps[i + 1] != '\0') 1789 i++; 1790 break; 1791 1792 /* 1793 * Superuser status. 1794 * 1795 * '$' for normal users, '#' for root. 1796 */ 1797 case '$': 1798 ps[i] = (geteuid() != 0) ? '$' : '#'; 1799 break; 1800 1801 /* 1802 * A literal \. 1803 */ 1804 case '\\': 1805 ps[i] = '\\'; 1806 break; 1807 1808 /* 1809 * Emit unrecognized formats verbatim. 1810 */ 1811 default: 1812 ps[i++] = '\\'; 1813 ps[i] = *fmt; 1814 break; 1815 } 1816 else 1817 ps[i] = *fmt; 1818 ps[i] = '\0'; 1819 return (ps); 1820 } 1821