1 /* $NetBSD: parser.c,v 1.120 2016/06/01 02:47:05 kre Exp $ */ 2 3 /*- 4 * Copyright (c) 1991, 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 * Kenneth Almquist. 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 <sys/cdefs.h> 36 #ifndef lint 37 #if 0 38 static char sccsid[] = "@(#)parser.c 8.7 (Berkeley) 5/16/95"; 39 #else 40 __RCSID("$NetBSD: parser.c,v 1.120 2016/06/01 02:47:05 kre Exp $"); 41 #endif 42 #endif /* not lint */ 43 44 #include <stdio.h> 45 #include <stdlib.h> 46 #include <limits.h> 47 48 #include "shell.h" 49 #include "parser.h" 50 #include "nodes.h" 51 #include "expand.h" /* defines rmescapes() */ 52 #include "eval.h" /* defines commandname */ 53 #include "syntax.h" 54 #include "options.h" 55 #include "input.h" 56 #include "output.h" 57 #include "var.h" 58 #include "error.h" 59 #include "memalloc.h" 60 #include "mystring.h" 61 #include "alias.h" 62 #include "show.h" 63 #ifndef SMALL 64 #include "myhistedit.h" 65 #endif 66 67 /* 68 * Shell command parser. 69 */ 70 71 /* values returned by readtoken */ 72 #include "token.h" 73 74 #define OPENBRACE '{' 75 #define CLOSEBRACE '}' 76 77 78 struct heredoc { 79 struct heredoc *next; /* next here document in list */ 80 union node *here; /* redirection node */ 81 char *eofmark; /* string indicating end of input */ 82 int striptabs; /* if set, strip leading tabs */ 83 int startline; /* line number where << seen */ 84 }; 85 86 87 88 static int noalias = 0; /* when set, don't handle aliases */ 89 struct heredoc *heredoclist; /* list of here documents to read */ 90 int parsebackquote; /* nonzero if we are inside backquotes */ 91 int doprompt; /* if set, prompt the user */ 92 int needprompt; /* true if interactive and at start of line */ 93 int lasttoken; /* last token read */ 94 MKINIT int tokpushback; /* last token pushed back */ 95 char *wordtext; /* text of last word returned by readtoken */ 96 MKINIT int checkkwd; /* 1 == check for kwds, 2 == also eat newlines */ 97 struct nodelist *backquotelist; 98 union node *redirnode; 99 struct heredoc *heredoc; 100 int quoteflag; /* set if (part of) last token was quoted */ 101 int startlinno; /* line # where last token started */ 102 int funclinno; /* line # where the current function started */ 103 104 105 STATIC union node *list(int, int); 106 STATIC union node *andor(void); 107 STATIC union node *pipeline(void); 108 STATIC union node *command(void); 109 STATIC union node *simplecmd(union node **, union node *); 110 STATIC union node *makename(void); 111 STATIC void parsefname(void); 112 STATIC void slurp_heredoc(char *const, const int, const int); 113 STATIC void readheredocs(void); 114 STATIC int peektoken(void); 115 STATIC int readtoken(void); 116 STATIC int xxreadtoken(void); 117 STATIC int readtoken1(int, char const *, int); 118 STATIC int noexpand(char *); 119 STATIC void synexpect(int, const char *) __dead; 120 STATIC void synerror(const char *) __dead; 121 STATIC void setprompt(int); 122 123 124 static const char EOFhere[] = "EOF reading here (<<) document"; 125 126 127 /* 128 * Read and parse a command. Returns NEOF on end of file. (NULL is a 129 * valid parse tree indicating a blank line.) 130 */ 131 132 union node * 133 parsecmd(int interact) 134 { 135 int t; 136 union node *n; 137 138 tokpushback = 0; 139 doprompt = interact; 140 if (doprompt) 141 setprompt(1); 142 else 143 setprompt(0); 144 needprompt = 0; 145 t = readtoken(); 146 if (t == TEOF) 147 return NEOF; 148 if (t == TNL) 149 return NULL; 150 tokpushback++; 151 n = list(1, 0); 152 if (heredoclist) 153 error("%d: Here document (<<%s) expected but not present", 154 heredoclist->startline, heredoclist->eofmark); 155 return n; 156 } 157 158 159 STATIC union node * 160 list(int nlflag, int erflag) 161 { 162 union node *n1, *n2, *n3; 163 int tok; 164 TRACE(("list(%d,%d): entered\n", nlflag, erflag)); 165 166 checkkwd = 2; 167 if (nlflag == 0 && tokendlist[peektoken()]) 168 return NULL; 169 n1 = NULL; 170 for (;;) { 171 n2 = andor(); 172 tok = readtoken(); 173 if (tok == TBACKGND) { 174 if (n2->type == NCMD || n2->type == NPIPE) { 175 n2->ncmd.backgnd = 1; 176 } else if (n2->type == NREDIR) { 177 n2->type = NBACKGND; 178 } else { 179 n3 = stalloc(sizeof(struct nredir)); 180 n3->type = NBACKGND; 181 n3->nredir.n = n2; 182 n3->nredir.redirect = NULL; 183 n2 = n3; 184 } 185 } 186 if (n1 == NULL) { 187 n1 = n2; 188 } 189 else { 190 n3 = stalloc(sizeof(struct nbinary)); 191 n3->type = NSEMI; 192 n3->nbinary.ch1 = n1; 193 n3->nbinary.ch2 = n2; 194 n1 = n3; 195 } 196 switch (tok) { 197 case TBACKGND: 198 case TSEMI: 199 tok = readtoken(); 200 /* FALLTHROUGH */ 201 case TNL: 202 if (tok == TNL) { 203 readheredocs(); 204 if (nlflag) 205 return n1; 206 } else { 207 tokpushback++; 208 } 209 checkkwd = 2; 210 if (tokendlist[peektoken()]) 211 return n1; 212 break; 213 case TEOF: 214 pungetc(); /* push back EOF on input */ 215 return n1; 216 default: 217 if (nlflag || erflag) 218 synexpect(-1, 0); 219 tokpushback++; 220 return n1; 221 } 222 } 223 } 224 225 STATIC union node * 226 andor(void) 227 { 228 union node *n1, *n2, *n3; 229 int t; 230 231 TRACE(("andor: entered\n")); 232 n1 = pipeline(); 233 for (;;) { 234 if ((t = readtoken()) == TAND) { 235 t = NAND; 236 } else if (t == TOR) { 237 t = NOR; 238 } else { 239 tokpushback++; 240 return n1; 241 } 242 n2 = pipeline(); 243 n3 = stalloc(sizeof(struct nbinary)); 244 n3->type = t; 245 n3->nbinary.ch1 = n1; 246 n3->nbinary.ch2 = n2; 247 n1 = n3; 248 } 249 } 250 251 STATIC union node * 252 pipeline(void) 253 { 254 union node *n1, *n2, *pipenode; 255 struct nodelist *lp, *prev; 256 int negate; 257 258 TRACE(("pipeline: entered\n")); 259 260 negate = 0; 261 checkkwd = 2; 262 while (readtoken() == TNOT) { 263 TRACE(("pipeline: TNOT recognized\n")); 264 negate = !negate; 265 } 266 tokpushback++; 267 n1 = command(); 268 if (readtoken() == TPIPE) { 269 pipenode = stalloc(sizeof(struct npipe)); 270 pipenode->type = NPIPE; 271 pipenode->npipe.backgnd = 0; 272 lp = stalloc(sizeof(struct nodelist)); 273 pipenode->npipe.cmdlist = lp; 274 lp->n = n1; 275 do { 276 prev = lp; 277 lp = stalloc(sizeof(struct nodelist)); 278 lp->n = command(); 279 prev->next = lp; 280 } while (readtoken() == TPIPE); 281 lp->next = NULL; 282 n1 = pipenode; 283 } 284 tokpushback++; 285 if (negate) { 286 TRACE(("negate pipeline\n")); 287 n2 = stalloc(sizeof(struct nnot)); 288 n2->type = NNOT; 289 n2->nnot.com = n1; 290 return n2; 291 } else 292 return n1; 293 } 294 295 296 297 STATIC union node * 298 command(void) 299 { 300 union node *n1, *n2; 301 union node *ap, **app; 302 union node *cp, **cpp; 303 union node *redir, **rpp; 304 int t, negate = 0; 305 306 TRACE(("command: entered\n")); 307 308 checkkwd = 2; 309 redir = NULL; 310 n1 = NULL; 311 rpp = &redir; 312 313 /* Check for redirection which may precede command */ 314 while (readtoken() == TREDIR) { 315 *rpp = n2 = redirnode; 316 rpp = &n2->nfile.next; 317 parsefname(); 318 } 319 tokpushback++; 320 321 while (readtoken() == TNOT) { 322 TRACE(("command: TNOT recognized\n")); 323 negate = !negate; 324 } 325 tokpushback++; 326 327 switch (readtoken()) { 328 case TIF: 329 n1 = stalloc(sizeof(struct nif)); 330 n1->type = NIF; 331 n1->nif.test = list(0, 0); 332 if (readtoken() != TTHEN) 333 synexpect(TTHEN, 0); 334 n1->nif.ifpart = list(0, 0); 335 n2 = n1; 336 while (readtoken() == TELIF) { 337 n2->nif.elsepart = stalloc(sizeof(struct nif)); 338 n2 = n2->nif.elsepart; 339 n2->type = NIF; 340 n2->nif.test = list(0, 0); 341 if (readtoken() != TTHEN) 342 synexpect(TTHEN, 0); 343 n2->nif.ifpart = list(0, 0); 344 } 345 if (lasttoken == TELSE) 346 n2->nif.elsepart = list(0, 0); 347 else { 348 n2->nif.elsepart = NULL; 349 tokpushback++; 350 } 351 if (readtoken() != TFI) 352 synexpect(TFI, 0); 353 checkkwd = 1; 354 break; 355 case TWHILE: 356 case TUNTIL: { 357 int got; 358 n1 = stalloc(sizeof(struct nbinary)); 359 n1->type = (lasttoken == TWHILE)? NWHILE : NUNTIL; 360 n1->nbinary.ch1 = list(0, 0); 361 if ((got=readtoken()) != TDO) { 362 TRACE(("expecting DO got %s %s\n", tokname[got], got == TWORD ? wordtext : "")); 363 synexpect(TDO, 0); 364 } 365 n1->nbinary.ch2 = list(0, 0); 366 if (readtoken() != TDONE) 367 synexpect(TDONE, 0); 368 checkkwd = 1; 369 break; 370 } 371 case TFOR: 372 if (readtoken() != TWORD || quoteflag || ! goodname(wordtext)) 373 synerror("Bad for loop variable"); 374 n1 = stalloc(sizeof(struct nfor)); 375 n1->type = NFOR; 376 n1->nfor.var = wordtext; 377 if (readtoken() == TWORD && ! quoteflag && equal(wordtext, "in")) { 378 app = ≈ 379 while (readtoken() == TWORD) { 380 n2 = stalloc(sizeof(struct narg)); 381 n2->type = NARG; 382 n2->narg.text = wordtext; 383 n2->narg.backquote = backquotelist; 384 *app = n2; 385 app = &n2->narg.next; 386 } 387 *app = NULL; 388 n1->nfor.args = ap; 389 if (lasttoken != TNL && lasttoken != TSEMI) 390 synexpect(-1, 0); 391 } else { 392 static char argvars[5] = { 393 CTLVAR, VSNORMAL|VSQUOTE, '@', '=', '\0' 394 }; 395 n2 = stalloc(sizeof(struct narg)); 396 n2->type = NARG; 397 n2->narg.text = argvars; 398 n2->narg.backquote = NULL; 399 n2->narg.next = NULL; 400 n1->nfor.args = n2; 401 /* 402 * Newline or semicolon here is optional (but note 403 * that the original Bourne shell only allowed NL). 404 */ 405 if (lasttoken != TNL && lasttoken != TSEMI) 406 tokpushback++; 407 } 408 checkkwd = 2; 409 if ((t = readtoken()) == TDO) 410 t = TDONE; 411 else if (t == TBEGIN) 412 t = TEND; 413 else 414 synexpect(-1, 0); 415 n1->nfor.body = list(0, 0); 416 if (readtoken() != t) 417 synexpect(t, 0); 418 checkkwd = 1; 419 break; 420 case TCASE: 421 n1 = stalloc(sizeof(struct ncase)); 422 n1->type = NCASE; 423 if (readtoken() != TWORD) 424 synexpect(TWORD, 0); 425 n1->ncase.expr = n2 = stalloc(sizeof(struct narg)); 426 n2->type = NARG; 427 n2->narg.text = wordtext; 428 n2->narg.backquote = backquotelist; 429 n2->narg.next = NULL; 430 while (readtoken() == TNL); 431 if (lasttoken != TWORD || ! equal(wordtext, "in")) 432 synexpect(-1, "in"); 433 cpp = &n1->ncase.cases; 434 noalias = 1; 435 checkkwd = 2, readtoken(); 436 /* 437 * Both ksh and bash accept 'case x in esac' 438 * so configure scripts started taking advantage of this. 439 * The page: http://pubs.opengroup.org/onlinepubs/\ 440 * 009695399/utilities/xcu_chap02.html contradicts itself, 441 * as to if this is legal; the "Case Conditional Format" 442 * paragraph shows one case is required, but the "Grammar" 443 * section shows a grammar that explicitly allows the no 444 * case option. 445 */ 446 while (lasttoken != TESAC) { 447 *cpp = cp = stalloc(sizeof(struct nclist)); 448 if (lasttoken == TLP) 449 readtoken(); 450 cp->type = NCLIST; 451 app = &cp->nclist.pattern; 452 for (;;) { 453 *app = ap = stalloc(sizeof(struct narg)); 454 ap->type = NARG; 455 ap->narg.text = wordtext; 456 ap->narg.backquote = backquotelist; 457 if (checkkwd = 2, readtoken() != TPIPE) 458 break; 459 app = &ap->narg.next; 460 readtoken(); 461 } 462 ap->narg.next = NULL; 463 noalias = 0; 464 if (lasttoken != TRP) { 465 synexpect(TRP, 0); 466 } 467 cp->nclist.body = list(0, 0); 468 469 checkkwd = 2; 470 if ((t = readtoken()) != TESAC) { 471 if (t != TENDCASE) { 472 noalias = 0; 473 synexpect(TENDCASE, 0); 474 } else { 475 noalias = 1; 476 checkkwd = 2; 477 readtoken(); 478 } 479 } 480 cpp = &cp->nclist.next; 481 } 482 noalias = 0; 483 *cpp = NULL; 484 checkkwd = 1; 485 break; 486 case TLP: 487 n1 = stalloc(sizeof(struct nredir)); 488 n1->type = NSUBSHELL; 489 n1->nredir.n = list(0, 0); 490 n1->nredir.redirect = NULL; 491 if (n1->nredir.n == NULL) 492 synexpect(-1, 0); 493 if (readtoken() != TRP) 494 synexpect(TRP, 0); 495 checkkwd = 1; 496 break; 497 case TBEGIN: 498 n1 = list(0, 0); 499 if (posix && n1 == NULL) 500 synexpect(-1, 0); 501 if (readtoken() != TEND) 502 synexpect(TEND, 0); 503 checkkwd = 1; 504 break; 505 506 case TSEMI: 507 case TAND: 508 case TOR: 509 case TPIPE: 510 case TNL: 511 case TEOF: 512 case TRP: 513 /* 514 * simple commands must have something in them, 515 * either a word (which at this point includes a=b) 516 * or a redirection. If we reached the end of the 517 * command (which one of these tokens indicates) 518 * when we are just starting, and have not had a 519 * redirect, then ... 520 * 521 * nb: it is still possible to end up with empty 522 * simple commands, if the "command" is a var 523 * expansion that produces nothing 524 * X= ; $X && $X 525 * --> && 526 * I am not sure if this is intended to be legal or not. 527 */ 528 if (!redir) 529 synexpect(-1, 0); 530 case TWORD: 531 tokpushback++; 532 n1 = simplecmd(rpp, redir); 533 goto checkneg; 534 case TENDCASE: 535 if (redir) { 536 tokpushback++; 537 goto checkneg; 538 } 539 /* FALLTHROUGH */ 540 default: 541 synexpect(-1, 0); 542 /* NOTREACHED */ 543 } 544 545 /* Now check for redirection which may follow command */ 546 while (readtoken() == TREDIR) { 547 *rpp = n2 = redirnode; 548 rpp = &n2->nfile.next; 549 parsefname(); 550 } 551 tokpushback++; 552 *rpp = NULL; 553 if (redir) { 554 if (n1->type != NSUBSHELL) { 555 n2 = stalloc(sizeof(struct nredir)); 556 n2->type = NREDIR; 557 n2->nredir.n = n1; 558 n1 = n2; 559 } 560 n1->nredir.redirect = redir; 561 } 562 563 checkneg: 564 if (negate) { 565 TRACE(("negate command\n")); 566 n2 = stalloc(sizeof(struct nnot)); 567 n2->type = NNOT; 568 n2->nnot.com = n1; 569 return n2; 570 } 571 else 572 return n1; 573 } 574 575 576 STATIC union node * 577 simplecmd(union node **rpp, union node *redir) 578 { 579 union node *args, **app; 580 union node *n = NULL, *n2; 581 int negate = 0; 582 583 /* If we don't have any redirections already, then we must reset */ 584 /* rpp to be the address of the local redir variable. */ 585 if (redir == 0) 586 rpp = &redir; 587 588 args = NULL; 589 app = &args; 590 591 while (readtoken() == TNOT) { 592 TRACE(("simplcmd: TNOT recognized\n")); 593 negate = !negate; 594 } 595 tokpushback++; 596 597 for (;;) { 598 if (readtoken() == TWORD) { 599 n = stalloc(sizeof(struct narg)); 600 n->type = NARG; 601 n->narg.text = wordtext; 602 n->narg.backquote = backquotelist; 603 *app = n; 604 app = &n->narg.next; 605 } else if (lasttoken == TREDIR) { 606 *rpp = n = redirnode; 607 rpp = &n->nfile.next; 608 parsefname(); /* read name of redirection file */ 609 } else if (lasttoken == TLP && app == &args->narg.next 610 && redir == 0) { 611 /* We have a function */ 612 if (readtoken() != TRP) 613 synexpect(TRP, 0); 614 funclinno = plinno; 615 rmescapes(n->narg.text); 616 if (strchr(n->narg.text, '/')) 617 synerror("Bad function name"); 618 n->type = NDEFUN; 619 n->narg.next = command(); 620 funclinno = 0; 621 goto checkneg; 622 } else { 623 tokpushback++; 624 break; 625 } 626 } 627 628 if (args == NULL && redir == NULL) 629 synexpect(-1, 0); 630 *app = NULL; 631 *rpp = NULL; 632 n = stalloc(sizeof(struct ncmd)); 633 n->type = NCMD; 634 n->ncmd.backgnd = 0; 635 n->ncmd.args = args; 636 n->ncmd.redirect = redir; 637 638 checkneg: 639 if (negate) { 640 TRACE(("negate simplecmd\n")); 641 n2 = stalloc(sizeof(struct nnot)); 642 n2->type = NNOT; 643 n2->nnot.com = n; 644 return n2; 645 } 646 else 647 return n; 648 } 649 650 STATIC union node * 651 makename(void) 652 { 653 union node *n; 654 655 n = stalloc(sizeof(struct narg)); 656 n->type = NARG; 657 n->narg.next = NULL; 658 n->narg.text = wordtext; 659 n->narg.backquote = backquotelist; 660 return n; 661 } 662 663 void 664 fixredir(union node *n, const char *text, int err) 665 { 666 TRACE(("Fix redir %s %d\n", text, err)); 667 if (!err) 668 n->ndup.vname = NULL; 669 670 if (is_number(text)) 671 n->ndup.dupfd = number(text); 672 else if (text[0] == '-' && text[1] == '\0') 673 n->ndup.dupfd = -1; 674 else { 675 676 if (err) 677 synerror("Bad fd number"); 678 else 679 n->ndup.vname = makename(); 680 } 681 } 682 683 684 STATIC void 685 parsefname(void) 686 { 687 union node *n = redirnode; 688 689 if (readtoken() != TWORD) 690 synexpect(-1, 0); 691 if (n->type == NHERE) { 692 struct heredoc *here = heredoc; 693 struct heredoc *p; 694 695 if (quoteflag == 0) 696 n->type = NXHERE; 697 TRACE(("Here document %d\n", n->type)); 698 if (here->striptabs) { 699 while (*wordtext == '\t') 700 wordtext++; 701 } 702 703 /* 704 * this test is not really necessary, we are not 705 * required to expand wordtext, but there's no reason 706 * it cannot be $$ or something like that - that would 707 * not mean the pid, but literally two '$' characters. 708 * There is no need for limits on what the word can be. 709 * However, it needs to stay literal as entered, not 710 * have $ converted to CTLVAR or something, which as 711 * the parser is, at the minute, is impossible to prevent. 712 * So, leave it like this until the rest of the parser is fixed. 713 */ 714 if (! noexpand(wordtext)) 715 synerror("Illegal eof marker for << redirection"); 716 717 rmescapes(wordtext); 718 here->eofmark = wordtext; 719 here->next = NULL; 720 if (heredoclist == NULL) 721 heredoclist = here; 722 else { 723 for (p = heredoclist ; p->next ; p = p->next) 724 continue; 725 p->next = here; 726 } 727 } else if (n->type == NTOFD || n->type == NFROMFD) { 728 fixredir(n, wordtext, 0); 729 } else { 730 n->nfile.fname = makename(); 731 } 732 } 733 734 /* 735 * Check to see whether we are at the end of the here document. When this 736 * is called, c is set to the first character of the next input line. If 737 * we are at the end of the here document, this routine sets the c to PEOF. 738 * The new value of c is returned. 739 */ 740 741 static int 742 checkend(int c, char * const eofmark, const int striptabs) 743 { 744 if (striptabs) { 745 while (c == '\t') 746 c = pgetc(); 747 } 748 if (c == PEOF) { 749 if (*eofmark == '\0') 750 return (c); 751 synerror(EOFhere); 752 } 753 if (c == *eofmark) { 754 int c2; 755 char *q; 756 757 for (q = eofmark + 1; c2 = pgetc(), *q != '\0' && c2 == *q; q++) 758 ; 759 if ((c2 == PEOF || c2 == '\n') && *q == '\0') { 760 c = PEOF; 761 if (c2 == '\n') { 762 plinno++; 763 needprompt = doprompt; 764 } 765 } else { 766 pungetc(); 767 pushstring(eofmark + 1, q - (eofmark + 1), NULL); 768 } 769 } else if (c == '\n' && *eofmark == '\0') { 770 c = PEOF; 771 plinno++; 772 needprompt = doprompt; 773 } 774 return (c); 775 } 776 777 778 /* 779 * Input any here documents. 780 */ 781 782 STATIC void 783 slurp_heredoc(char *const eofmark, const int striptabs, const int sq) 784 { 785 int c; 786 char *out; 787 788 c = pgetc(); 789 790 /* 791 * If we hit EOF on the input, and the eofmark is a null string ('') 792 * we consider this empty line to be the eofmark, and exit without err. 793 */ 794 if (c == PEOF && *eofmark != '\0') 795 synerror(EOFhere); 796 797 STARTSTACKSTR(out); 798 799 while ((c = checkend(c, eofmark, striptabs)) != PEOF) { 800 do { 801 if (sq) { 802 /* 803 * in single quoted mode (eofmark quoted) 804 * all we look for is \n so we can check 805 * for the epfmark - everything saved literally. 806 */ 807 STPUTC(c, out); 808 if (c == '\n') 809 break; 810 continue; 811 } 812 /* 813 * In double quoted (non-quoted eofmark) 814 * we must handle \ followed by \n here 815 * otherwise we can mismatch the end mark. 816 * All other uses of \ will be handled later 817 * when the here doc is expanded. 818 * 819 * This also makes sure \\ followed by \n does 820 * not suppress the newline (the \ quotes itself) 821 */ 822 if (c == '\\') { /* A backslash */ 823 c = pgetc(); /* followed by */ 824 if (c == '\n') /* a newline? */ 825 continue; /* y:drop both */ 826 STPUTC('\\', out); /* else keep \ */ 827 } 828 STPUTC(c, out); /* keep the char */ 829 if (c == '\n') /* at end of line */ 830 break; /* look for eofmark */ 831 832 } while ((c = pgetc()) != PEOF); 833 834 /* 835 * If we have read a line, and reached EOF, without 836 * finding the eofmark, whether the EOF comes before 837 * or immediately after the \n, that is an error. 838 */ 839 if (c == PEOF || (c = pgetc()) == PEOF) 840 synerror(EOFhere); 841 } 842 STPUTC('\0', out); 843 844 c = out - stackblock(); 845 out = stackblock(); 846 grabstackblock(c); 847 wordtext = out; 848 849 TRACE(("Slurped a heredoc (to '%s')%s: len %d, \"%.16s\"...\n", 850 eofmark, striptabs ? " tab stripped" : "", c, wordtext)); 851 } 852 853 STATIC void 854 readheredocs(void) 855 { 856 struct heredoc *here; 857 union node *n; 858 859 while (heredoclist) { 860 here = heredoclist; 861 heredoclist = here->next; 862 if (needprompt) { 863 setprompt(2); 864 needprompt = 0; 865 } 866 867 slurp_heredoc(here->eofmark, here->striptabs, 868 here->here->nhere.type == NHERE); 869 870 n = stalloc(sizeof(struct narg)); 871 n->narg.type = NARG; 872 n->narg.next = NULL; 873 n->narg.text = wordtext; 874 n->narg.backquote = backquotelist; 875 here->here->nhere.doc = n; 876 877 if (here->here->nhere.type == NHERE) 878 continue; 879 880 /* 881 * Now "parse" here docs that have unquoted eofmarkers. 882 */ 883 setinputstring(wordtext, 1); 884 readtoken1(pgetc(), DQSYNTAX, 1); 885 n->narg.text = wordtext; 886 n->narg.backquote = backquotelist; 887 popfile(); 888 } 889 } 890 891 STATIC int 892 peektoken(void) 893 { 894 int t; 895 896 t = readtoken(); 897 tokpushback++; 898 return (t); 899 } 900 901 STATIC int 902 readtoken(void) 903 { 904 int t; 905 int savecheckkwd = checkkwd; 906 #ifdef DEBUG 907 int alreadyseen = tokpushback; 908 #endif 909 struct alias *ap; 910 911 top: 912 t = xxreadtoken(); 913 914 if (checkkwd) { 915 /* 916 * eat newlines 917 */ 918 if (checkkwd == 2) { 919 checkkwd = 0; 920 while (t == TNL) { 921 readheredocs(); 922 t = xxreadtoken(); 923 } 924 } else 925 checkkwd = 0; 926 /* 927 * check for keywords and aliases 928 */ 929 if (t == TWORD && !quoteflag) { 930 const char *const *pp; 931 932 for (pp = parsekwd; *pp; pp++) { 933 if (**pp == *wordtext && equal(*pp, wordtext)) { 934 lasttoken = t = pp - 935 parsekwd + KWDOFFSET; 936 TRACE(("keyword %s recognized\n", tokname[t])); 937 goto out; 938 } 939 } 940 if (!noalias && 941 (ap = lookupalias(wordtext, 1)) != NULL) { 942 pushstring(ap->val, strlen(ap->val), ap); 943 checkkwd = savecheckkwd; 944 goto top; 945 } 946 } 947 out: 948 checkkwd = (t == TNOT) ? savecheckkwd : 0; 949 } 950 TRACE(("%stoken %s %s\n", alreadyseen ? "reread " : "", tokname[t], t == TWORD ? wordtext : "")); 951 return (t); 952 } 953 954 955 /* 956 * Read the next input token. 957 * If the token is a word, we set backquotelist to the list of cmds in 958 * backquotes. We set quoteflag to true if any part of the word was 959 * quoted. 960 * If the token is TREDIR, then we set redirnode to a structure containing 961 * the redirection. 962 * In all cases, the variable startlinno is set to the number of the line 963 * on which the token starts. 964 * 965 * [Change comment: here documents and internal procedures] 966 * [Readtoken shouldn't have any arguments. Perhaps we should make the 967 * word parsing code into a separate routine. In this case, readtoken 968 * doesn't need to have any internal procedures, but parseword does. 969 * We could also make parseoperator in essence the main routine, and 970 * have parseword (readtoken1?) handle both words and redirection.] 971 */ 972 973 #define RETURN(token) return lasttoken = token 974 975 STATIC int 976 xxreadtoken(void) 977 { 978 int c; 979 980 if (tokpushback) { 981 tokpushback = 0; 982 return lasttoken; 983 } 984 if (needprompt) { 985 setprompt(2); 986 needprompt = 0; 987 } 988 startlinno = plinno; 989 for (;;) { /* until token or start of word found */ 990 c = pgetc_macro(); 991 switch (c) { 992 case ' ': case '\t': 993 continue; 994 case '#': 995 while ((c = pgetc()) != '\n' && c != PEOF) 996 continue; 997 pungetc(); 998 continue; 999 1000 case '\n': 1001 plinno++; 1002 needprompt = doprompt; 1003 RETURN(TNL); 1004 case PEOF: 1005 RETURN(TEOF); 1006 1007 case '&': 1008 if (pgetc() == '&') 1009 RETURN(TAND); 1010 pungetc(); 1011 RETURN(TBACKGND); 1012 case '|': 1013 if (pgetc() == '|') 1014 RETURN(TOR); 1015 pungetc(); 1016 RETURN(TPIPE); 1017 case ';': 1018 if (pgetc() == ';') 1019 RETURN(TENDCASE); 1020 pungetc(); 1021 RETURN(TSEMI); 1022 case '(': 1023 RETURN(TLP); 1024 case ')': 1025 RETURN(TRP); 1026 1027 case '\\': 1028 switch (pgetc()) { 1029 case '\n': 1030 startlinno = ++plinno; 1031 if (doprompt) 1032 setprompt(2); 1033 else 1034 setprompt(0); 1035 continue; 1036 case PEOF: 1037 RETURN(TEOF); 1038 default: 1039 pungetc(); 1040 break; 1041 } 1042 /* FALLTHROUGH */ 1043 default: 1044 return readtoken1(c, BASESYNTAX, 0); 1045 } 1046 } 1047 #undef RETURN 1048 } 1049 1050 1051 1052 /* 1053 * If eofmark is NULL, read a word or a redirection symbol. If eofmark 1054 * is not NULL, read a here document. In the latter case, eofmark is the 1055 * word which marks the end of the document and striptabs is true if 1056 * leading tabs should be stripped from the document. The argument firstc 1057 * is the first character of the input token or document. 1058 * 1059 * Because C does not have internal subroutines, I have simulated them 1060 * using goto's to implement the subroutine linkage. The following macros 1061 * will run code that appears at the end of readtoken1. 1062 */ 1063 1064 /* 1065 * We used to remember only the current syntax, variable nesting level, 1066 * double quote state for each var nesting level, and arith nesting 1067 * level (unrelated to var nesting) and one prev syntax when in arith 1068 * syntax. This worked for simple cases, but can't handle arith inside 1069 * var expansion inside arith inside var with some quoted and some not. 1070 * 1071 * Inspired by FreeBSD's implementation (though it was the obvious way) 1072 * though implemented differently, we now have a stack that keeps track 1073 * of what we are doing now, and what we were doing previously. 1074 * Every time something changes, which will eventually end and should 1075 * revert to the previous state, we push this stack, and then pop it 1076 * again later (that is every ${} with an operator (to parse the word 1077 * or pattern that follows) ${x} and $x are too simple to need it) 1078 * $(( )) $( ) and "...". Always. Really, always! 1079 * 1080 * The stack is implemented as one static (on the C stack) base block 1081 * containing LEVELS_PER_BLOCK (8) stack entries, which should be 1082 * enough for the vast majority of cases. For torture tests, we 1083 * malloc more blocks as needed. All accesses through the inline 1084 * functions below. 1085 */ 1086 1087 /* 1088 * varnest & arinest will typically be 0 or 1 1089 * (varnest can increment in usages like ${x=${y}} but probably 1090 * does not really need to) 1091 * parenlevel allows balancing parens inside a $(( )), it is reset 1092 * at each new nesting level ( $(( ( x + 3 ${unset-)} )) does not work. 1093 * quoted is special - we need to know 2 things ... are we inside "..." 1094 * (even if inherited from some previous nesting level) and was there 1095 * an opening '"' at this level (so the next will be closing). 1096 * "..." can span nesting levels, but cannot be opened in one and 1097 * closed in a different one. 1098 * To handle this, "quoted" has two fields, the bottom 4 (really 2) 1099 * bits are 0, 1, or 2, for un, single, and double quoted (single quoted 1100 * is really so special that this setting is not very important) 1101 * and 0x10 that indicates that an opening quote has been seen. 1102 * The bottom 4 bits are inherited, the 0x10 bit is not. 1103 */ 1104 struct tokenstate { 1105 const char *ts_syntax; 1106 unsigned short ts_parenlevel; /* counters */ 1107 unsigned short ts_varnest; /* 64000 levels should be enough! */ 1108 unsigned short ts_arinest; 1109 unsigned short ts_quoted; /* 1 -> single, 2 -> double */ 1110 }; 1111 1112 #define NQ 0x00 /* Unquoted */ 1113 #define SQ 0x01 /* Single Quotes */ 1114 #define DQ 0x02 /* Double Quotes (or equivalent) */ 1115 #define QF 0x0F /* Mask to extract previous values */ 1116 #define QS 0x10 /* Quoting started at this level in stack */ 1117 1118 #define LEVELS_PER_BLOCK 8 1119 #define VSS struct statestack 1120 1121 struct statestack { 1122 VSS *prev; /* previous block in list */ 1123 int cur; /* which of our tokenstates is current */ 1124 struct tokenstate tokenstate[LEVELS_PER_BLOCK]; 1125 }; 1126 1127 static inline struct tokenstate * 1128 currentstate(VSS *stack) 1129 { 1130 return &stack->tokenstate[stack->cur]; 1131 } 1132 1133 static inline struct tokenstate * 1134 prevstate(VSS *stack) 1135 { 1136 if (stack->cur != 0) 1137 return &stack->tokenstate[stack->cur - 1]; 1138 if (stack->prev == NULL) /* cannot drop below base */ 1139 return &stack->tokenstate[0]; 1140 return &stack->prev->tokenstate[LEVELS_PER_BLOCK - 1]; 1141 } 1142 1143 static inline VSS * 1144 bump_state_level(VSS *stack) 1145 { 1146 struct tokenstate *os, *ts; 1147 1148 os = currentstate(stack); 1149 1150 if (++stack->cur >= LEVELS_PER_BLOCK) { 1151 VSS *ss; 1152 1153 ss = (VSS *)ckmalloc(sizeof (struct statestack)); 1154 ss->cur = 0; 1155 ss->prev = stack; 1156 stack = ss; 1157 } 1158 1159 ts = currentstate(stack); 1160 1161 ts->ts_parenlevel = 0; /* parens inside never match outside */ 1162 1163 ts->ts_quoted = os->ts_quoted & QF; /* these are default settings */ 1164 ts->ts_varnest = os->ts_varnest; 1165 ts->ts_arinest = os->ts_arinest; /* when appropriate */ 1166 ts->ts_syntax = os->ts_syntax; /* they will be altered */ 1167 1168 return stack; 1169 } 1170 1171 static inline VSS * 1172 drop_state_level(VSS *stack) 1173 { 1174 if (stack->cur == 0) { 1175 VSS *ss; 1176 1177 ss = stack; 1178 stack = ss->prev; 1179 if (stack == NULL) 1180 return ss; 1181 ckfree(ss); 1182 } 1183 --stack->cur; 1184 return stack; 1185 } 1186 1187 static inline void 1188 cleanup_state_stack(VSS *stack) 1189 { 1190 while (stack->prev != NULL) { 1191 stack->cur = 0; 1192 stack = drop_state_level(stack); 1193 } 1194 } 1195 1196 #define PARSESUB() {goto parsesub; parsesub_return:;} 1197 #define PARSEARITH() {goto parsearith; parsearith_return:;} 1198 1199 /* 1200 * The following macros all assume the existance of a local var "stack" 1201 * which contains a pointer to the current struct stackstate 1202 */ 1203 1204 /* 1205 * These are macros rather than inline funcs to avoid code churn as much 1206 * as possible - they replace macros of the same name used previously. 1207 */ 1208 #define ISDBLQUOTE() (currentstate(stack)->ts_quoted & QS) 1209 #define SETDBLQUOTE() (currentstate(stack)->ts_quoted = QS | DQ) 1210 #define CLRDBLQUOTE() (currentstate(stack)->ts_quoted = \ 1211 stack->cur != 0 || stack->prev ? \ 1212 prevstate(stack)->ts_quoted & QF : 0) 1213 1214 /* 1215 * This set are just to avoid excess typing and line lengths... 1216 * The ones that "look like" var names must be implemented to be lvalues 1217 */ 1218 #define syntax (currentstate(stack)->ts_syntax) 1219 #define parenlevel (currentstate(stack)->ts_parenlevel) 1220 #define varnest (currentstate(stack)->ts_varnest) 1221 #define arinest (currentstate(stack)->ts_arinest) 1222 #define quoted (currentstate(stack)->ts_quoted) 1223 #define TS_PUSH() (stack = bump_state_level(stack)) 1224 #define TS_POP() (stack = drop_state_level(stack)) 1225 1226 /* 1227 * Called to parse command substitutions. oldstyle is true if the command 1228 * is enclosed inside `` (otherwise it was enclosed in "$( )") 1229 * 1230 * Internally nlpp is a pointer to the head of the linked 1231 * list of commands (passed by reference), and savelen is the number of 1232 * characters on the top of the stack which must be preserved. 1233 */ 1234 static char * 1235 parsebackq(VSS *const stack, char * const in, 1236 struct nodelist **const pbqlist, const int oldstyle) 1237 { 1238 struct nodelist **nlpp; 1239 const int savepbq = parsebackquote; 1240 union node *n; 1241 char *out; 1242 char *str = NULL; 1243 char *volatile sstr = str; 1244 struct jmploc jmploc; 1245 struct jmploc *const savehandler = handler; 1246 const int savelen = in - stackblock(); 1247 int saveprompt; 1248 1249 if (setjmp(jmploc.loc)) { 1250 if (sstr) 1251 ckfree(__UNVOLATILE(sstr)); 1252 cleanup_state_stack(stack); 1253 parsebackquote = 0; 1254 handler = savehandler; 1255 longjmp(handler->loc, 1); 1256 } 1257 INTOFF; 1258 sstr = str = NULL; 1259 if (savelen > 0) { 1260 sstr = str = ckmalloc(savelen); 1261 memcpy(str, stackblock(), savelen); 1262 } 1263 handler = &jmploc; 1264 INTON; 1265 if (oldstyle) { 1266 /* We must read until the closing backquote, giving special 1267 treatment to some slashes, and then push the string and 1268 reread it as input, interpreting it normally. */ 1269 int pc; 1270 int psavelen; 1271 char *pstr; 1272 1273 /* 1274 * Because the entire `...` is read here, we don't 1275 * need to bother the state stack. That will be used 1276 * (as appropriate) when the processed string is re-read. 1277 */ 1278 STARTSTACKSTR(out); 1279 for (;;) { 1280 if (needprompt) { 1281 setprompt(2); 1282 needprompt = 0; 1283 } 1284 switch (pc = pgetc()) { 1285 case '`': 1286 goto done; 1287 1288 case '\\': 1289 if ((pc = pgetc()) == '\n') { 1290 plinno++; 1291 if (doprompt) 1292 setprompt(2); 1293 else 1294 setprompt(0); 1295 /* 1296 * If eating a newline, avoid putting 1297 * the newline into the new character 1298 * stream (via the STPUTC after the 1299 * switch). 1300 */ 1301 continue; 1302 } 1303 if (pc != '\\' && pc != '`' && pc != '$' 1304 && (!ISDBLQUOTE() || pc != '"')) 1305 STPUTC('\\', out); 1306 break; 1307 1308 case '\n': 1309 plinno++; 1310 needprompt = doprompt; 1311 break; 1312 1313 case PEOF: 1314 startlinno = plinno; 1315 synerror("EOF in backquote substitution"); 1316 break; 1317 1318 default: 1319 break; 1320 } 1321 STPUTC(pc, out); 1322 } 1323 done: 1324 STPUTC('\0', out); 1325 psavelen = out - stackblock(); 1326 if (psavelen > 0) { 1327 pstr = grabstackstr(out); 1328 setinputstring(pstr, 1); 1329 } 1330 } 1331 nlpp = pbqlist; 1332 while (*nlpp) 1333 nlpp = &(*nlpp)->next; 1334 *nlpp = stalloc(sizeof(struct nodelist)); 1335 (*nlpp)->next = NULL; 1336 parsebackquote = oldstyle; 1337 1338 if (oldstyle) { 1339 saveprompt = doprompt; 1340 doprompt = 0; 1341 } else 1342 saveprompt = 0; 1343 1344 n = list(0, oldstyle); 1345 1346 if (oldstyle) 1347 doprompt = saveprompt; 1348 else { 1349 if (readtoken() != TRP) { 1350 cleanup_state_stack(stack); 1351 synexpect(TRP, 0); 1352 } 1353 } 1354 1355 (*nlpp)->n = n; 1356 if (oldstyle) { 1357 /* 1358 * Start reading from old file again, ignoring any pushed back 1359 * tokens left from the backquote parsing 1360 */ 1361 popfile(); 1362 tokpushback = 0; 1363 } 1364 1365 while (stackblocksize() <= savelen) 1366 growstackblock(); 1367 STARTSTACKSTR(out); 1368 if (str) { 1369 memcpy(out, str, savelen); 1370 STADJUST(savelen, out); 1371 INTOFF; 1372 ckfree(str); 1373 sstr = str = NULL; 1374 INTON; 1375 } 1376 parsebackquote = savepbq; 1377 handler = savehandler; 1378 if (arinest || ISDBLQUOTE()) 1379 USTPUTC(CTLBACKQ | CTLQUOTE, out); 1380 else 1381 USTPUTC(CTLBACKQ, out); 1382 1383 return out; 1384 } 1385 1386 /* 1387 * Parse a redirection operator. The parameter "out" points to a string 1388 * specifying the fd to be redirected. It is guaranteed to be either "" 1389 * or a numeric string (for now anyway). The parameter "c" contains the 1390 * first character of the redirection operator. 1391 * 1392 * Note the string "out" is on the stack, which we are about to clobber, 1393 * so process it first... 1394 */ 1395 1396 static void 1397 parseredir(const char *out, int c) 1398 { 1399 union node *np; 1400 int fd; 1401 1402 fd = (*out == '\0') ? -1 : atoi(out); 1403 1404 np = stalloc(sizeof(struct nfile)); 1405 if (c == '>') { 1406 if (fd < 0) 1407 fd = 1; 1408 c = pgetc(); 1409 if (c == '>') 1410 np->type = NAPPEND; 1411 else if (c == '|') 1412 np->type = NCLOBBER; 1413 else if (c == '&') 1414 np->type = NTOFD; 1415 else { 1416 np->type = NTO; 1417 pungetc(); 1418 } 1419 } else { /* c == '<' */ 1420 if (fd < 0) 1421 fd = 0; 1422 switch (c = pgetc()) { 1423 case '<': 1424 if (sizeof (struct nfile) != sizeof (struct nhere)) { 1425 np = stalloc(sizeof(struct nhere)); 1426 np->nfile.fd = 0; 1427 } 1428 np->type = NHERE; 1429 heredoc = stalloc(sizeof(struct heredoc)); 1430 heredoc->here = np; 1431 heredoc->startline = plinno; 1432 if ((c = pgetc()) == '-') { 1433 heredoc->striptabs = 1; 1434 } else { 1435 heredoc->striptabs = 0; 1436 pungetc(); 1437 } 1438 break; 1439 1440 case '&': 1441 np->type = NFROMFD; 1442 break; 1443 1444 case '>': 1445 np->type = NFROMTO; 1446 break; 1447 1448 default: 1449 np->type = NFROM; 1450 pungetc(); 1451 break; 1452 } 1453 } 1454 np->nfile.fd = fd; 1455 1456 redirnode = np; /* this is the "value" of TRENODE */ 1457 } 1458 1459 1460 /* 1461 * The lowest level basic tokenizer. 1462 * 1463 * The next input byte (character) is in firstc, syn says which 1464 * syntax tables we are to use (basic, single or double quoted, or arith) 1465 * and magicq (used with sqsyntax and dqsyntax only) indicates that the 1466 * quote character itself is not special (used parsing here docs and similar) 1467 * 1468 * The result is the type of the next token (its value, when there is one, 1469 * is saved in the relevant global var - must fix that someday!) which is 1470 * also saved for re-reading ("lasttoken"). 1471 * 1472 * Overall, this routine does far more parsing than it is supposed to. 1473 * That will also need fixing, someday... 1474 */ 1475 STATIC int 1476 readtoken1(int firstc, char const *syn, int magicq) 1477 { 1478 int c; 1479 char * out; 1480 int len; 1481 struct nodelist *bqlist; 1482 int quotef; 1483 VSS static_stack; 1484 VSS *stack = &static_stack; 1485 1486 stack->prev = NULL; 1487 stack->cur = 0; 1488 1489 syntax = syn; 1490 1491 startlinno = plinno; 1492 varnest = 0; 1493 quoted = 0; 1494 if (syntax == DQSYNTAX) 1495 SETDBLQUOTE(); 1496 quotef = 0; 1497 bqlist = NULL; 1498 arinest = 0; 1499 parenlevel = 0; 1500 1501 STARTSTACKSTR(out); 1502 1503 for (c = firstc ;; c = pgetc_macro()) { /* until of token */ 1504 CHECKSTRSPACE(4, out); /* permit 4 calls to USTPUTC */ 1505 switch (syntax[c]) { 1506 case CNL: /* '\n' */ 1507 if (syntax == BASESYNTAX) 1508 break; /* exit loop */ 1509 USTPUTC(c, out); 1510 plinno++; 1511 if (doprompt) 1512 setprompt(2); 1513 else 1514 setprompt(0); 1515 continue; 1516 1517 case CWORD: 1518 USTPUTC(c, out); 1519 continue; 1520 case CCTL: 1521 if (!magicq || ISDBLQUOTE()) 1522 USTPUTC(CTLESC, out); 1523 USTPUTC(c, out); 1524 continue; 1525 case CBACK: /* backslash */ 1526 c = pgetc(); 1527 if (c == PEOF) { 1528 USTPUTC('\\', out); 1529 pungetc(); 1530 continue; 1531 } 1532 if (c == '\n') { 1533 plinno++; 1534 if (doprompt) 1535 setprompt(2); 1536 else 1537 setprompt(0); 1538 continue; 1539 } 1540 quotef = 1; /* current token is quoted */ 1541 if (ISDBLQUOTE() && c != '\\' && c != '`' && 1542 c != '$' && (c != '"' || magicq)) 1543 USTPUTC('\\', out); 1544 if (SQSYNTAX[c] == CCTL) 1545 USTPUTC(CTLESC, out); 1546 else if (!magicq) { 1547 USTPUTC(CTLQUOTEMARK, out); 1548 USTPUTC(c, out); 1549 if (varnest != 0) 1550 USTPUTC(CTLQUOTEEND, out); 1551 continue; 1552 } 1553 USTPUTC(c, out); 1554 continue; 1555 case CSQUOTE: 1556 if (syntax != SQSYNTAX) { 1557 if (!magicq) 1558 USTPUTC(CTLQUOTEMARK, out); 1559 quotef = 1; 1560 TS_PUSH(); 1561 syntax = SQSYNTAX; 1562 quoted = SQ; 1563 continue; 1564 } 1565 if (magicq && arinest == 0 && varnest == 0) { 1566 /* Ignore inside quoted here document */ 1567 USTPUTC(c, out); 1568 continue; 1569 } 1570 /* End of single quotes... */ 1571 TS_POP(); 1572 if (syntax == BASESYNTAX && varnest != 0) 1573 USTPUTC(CTLQUOTEEND, out); 1574 continue; 1575 case CDQUOTE: 1576 if (magicq && arinest == 0 && varnest == 0) { 1577 /* Ignore inside here document */ 1578 USTPUTC(c, out); 1579 continue; 1580 } 1581 quotef = 1; 1582 if (arinest) { 1583 if (ISDBLQUOTE()) { 1584 TS_POP(); 1585 } else { 1586 TS_PUSH(); 1587 syntax = DQSYNTAX; 1588 SETDBLQUOTE(); 1589 USTPUTC(CTLQUOTEMARK, out); 1590 } 1591 continue; 1592 } 1593 if (magicq) 1594 continue; 1595 if (ISDBLQUOTE()) { 1596 TS_POP(); 1597 if (varnest != 0) 1598 USTPUTC(CTLQUOTEEND, out); 1599 } else { 1600 TS_PUSH(); 1601 syntax = DQSYNTAX; 1602 SETDBLQUOTE(); 1603 USTPUTC(CTLQUOTEMARK, out); 1604 } 1605 continue; 1606 case CVAR: /* '$' */ 1607 PARSESUB(); /* parse substitution */ 1608 continue; 1609 case CENDVAR: /* CLOSEBRACE */ 1610 if (varnest > 0 && !ISDBLQUOTE()) { 1611 TS_POP(); 1612 USTPUTC(CTLENDVAR, out); 1613 } else { 1614 USTPUTC(c, out); 1615 } 1616 continue; 1617 case CLP: /* '(' in arithmetic */ 1618 parenlevel++; 1619 USTPUTC(c, out); 1620 continue;; 1621 case CRP: /* ')' in arithmetic */ 1622 if (parenlevel > 0) { 1623 USTPUTC(c, out); 1624 --parenlevel; 1625 } else { 1626 if (pgetc() == ')') { 1627 if (--arinest == 0) { 1628 TS_POP(); 1629 USTPUTC(CTLENDARI, out); 1630 } else 1631 USTPUTC(')', out); 1632 } else { 1633 /* 1634 * unbalanced parens 1635 * (don't 2nd guess - no error) 1636 */ 1637 pungetc(); 1638 USTPUTC(')', out); 1639 } 1640 } 1641 continue; 1642 case CBQUOTE: /* '`' */ 1643 out = parsebackq(stack, out, &bqlist, 1); 1644 continue; 1645 case CEOF: /* --> c == PEOF */ 1646 break; /* will exit loop */ 1647 default: 1648 if (varnest == 0 && !ISDBLQUOTE()) 1649 break; /* exit loop */ 1650 USTPUTC(c, out); 1651 continue; 1652 } 1653 break; /* break from switch -> break from for loop too */ 1654 } 1655 1656 if (syntax == ARISYNTAX) { 1657 cleanup_state_stack(stack); 1658 synerror("Missing '))'"); 1659 } 1660 if (syntax != BASESYNTAX && /* ! parsebackquote && */ !magicq) { 1661 cleanup_state_stack(stack); 1662 synerror("Unterminated quoted string"); 1663 } 1664 if (varnest != 0) { 1665 cleanup_state_stack(stack); 1666 startlinno = plinno; 1667 /* { */ 1668 synerror("Missing '}'"); 1669 } 1670 1671 USTPUTC('\0', out); 1672 len = out - stackblock(); 1673 out = stackblock(); 1674 1675 if (!magicq) { 1676 if ((c == '<' || c == '>') 1677 && quotef == 0 && (*out == '\0' || is_number(out))) { 1678 parseredir(out, c); 1679 cleanup_state_stack(stack); 1680 return lasttoken = TREDIR; 1681 } else { 1682 pungetc(); 1683 } 1684 } 1685 1686 quoteflag = quotef; 1687 backquotelist = bqlist; 1688 grabstackblock(len); 1689 wordtext = out; 1690 cleanup_state_stack(stack); 1691 return lasttoken = TWORD; 1692 /* end of readtoken routine */ 1693 1694 1695 /* 1696 * Parse a substitution. At this point, we have read the dollar sign 1697 * and nothing else. 1698 */ 1699 1700 parsesub: { 1701 char buf[10]; 1702 int subtype; 1703 int typeloc; 1704 int flags; 1705 char *p; 1706 static const char types[] = "}-+?="; 1707 int i; 1708 int linno; 1709 1710 c = pgetc(); 1711 if (c != '(' && c != OPENBRACE && !is_name(c) && !is_special(c)) { 1712 USTPUTC('$', out); 1713 pungetc(); 1714 } else if (c == '(') { /* $(command) or $((arith)) */ 1715 if (pgetc() == '(') { 1716 PARSEARITH(); 1717 } else { 1718 pungetc(); 1719 out = parsebackq(stack, out, &bqlist, 0); 1720 } 1721 } else { 1722 USTPUTC(CTLVAR, out); 1723 typeloc = out - stackblock(); 1724 USTPUTC(VSNORMAL, out); 1725 subtype = VSNORMAL; 1726 flags = 0; 1727 if (c == OPENBRACE) { 1728 c = pgetc(); 1729 if (c == '#') { 1730 if ((c = pgetc()) == CLOSEBRACE) 1731 c = '#'; 1732 else 1733 subtype = VSLENGTH; 1734 } 1735 else 1736 subtype = 0; 1737 } 1738 if (is_name(c)) { 1739 p = out; 1740 do { 1741 STPUTC(c, out); 1742 c = pgetc(); 1743 } while (is_in_name(c)); 1744 if (out - p == 6 && strncmp(p, "LINENO", 6) == 0) { 1745 /* Replace the variable name with the 1746 * current line number. */ 1747 linno = plinno; 1748 if (funclinno != 0) 1749 linno -= funclinno - 1; 1750 snprintf(buf, sizeof(buf), "%d", linno); 1751 STADJUST(-6, out); 1752 for (i = 0; buf[i] != '\0'; i++) 1753 STPUTC(buf[i], out); 1754 flags |= VSLINENO; 1755 } 1756 } else if (is_digit(c)) { 1757 do { 1758 USTPUTC(c, out); 1759 c = pgetc(); 1760 } while (subtype != VSNORMAL && is_digit(c)); 1761 } 1762 else if (is_special(c)) { 1763 USTPUTC(c, out); 1764 c = pgetc(); 1765 } 1766 else { 1767 badsub: 1768 cleanup_state_stack(stack); 1769 synerror("Bad substitution"); 1770 } 1771 1772 STPUTC('=', out); 1773 if (subtype == 0) { 1774 switch (c) { 1775 case ':': 1776 flags |= VSNUL; 1777 c = pgetc(); 1778 /*FALLTHROUGH*/ 1779 default: 1780 p = strchr(types, c); 1781 if (p == NULL) 1782 goto badsub; 1783 subtype = p - types + VSNORMAL; 1784 break; 1785 case '%': 1786 case '#': 1787 { 1788 int cc = c; 1789 subtype = c == '#' ? VSTRIMLEFT : 1790 VSTRIMRIGHT; 1791 c = pgetc(); 1792 if (c == cc) 1793 subtype++; 1794 else 1795 pungetc(); 1796 break; 1797 } 1798 } 1799 } else { 1800 pungetc(); 1801 } 1802 if (ISDBLQUOTE() || arinest) 1803 flags |= VSQUOTE; 1804 if (subtype >= VSTRIMLEFT && subtype <= VSTRIMRIGHTMAX) 1805 flags |= VSPATQ; 1806 *(stackblock() + typeloc) = subtype | flags; 1807 if (subtype != VSNORMAL) { 1808 TS_PUSH(); 1809 varnest++; 1810 arinest = 0; 1811 if (subtype > VSASSIGN) { /* # ## % %% */ 1812 syntax = BASESYNTAX; 1813 CLRDBLQUOTE(); 1814 } 1815 } 1816 } 1817 goto parsesub_return; 1818 } 1819 1820 1821 /* 1822 * Parse an arithmetic expansion (indicate start of one and set state) 1823 */ 1824 parsearith: { 1825 1826 if (syntax == ARISYNTAX) { 1827 /* 1828 * we collapse embedded arithmetic expansion to 1829 * parentheses, which should be equivalent 1830 */ 1831 USTPUTC('(', out); 1832 USTPUTC('(', out); 1833 /* 1834 * Need 2 of them because there will (should be) 1835 * two closing ))'s to follow later. 1836 */ 1837 parenlevel += 2; 1838 } else { 1839 TS_PUSH(); 1840 syntax = ARISYNTAX; 1841 ++arinest; 1842 varnest = 0; 1843 1844 USTPUTC(CTLARI, out); 1845 if (ISDBLQUOTE()) 1846 USTPUTC('"',out); 1847 else 1848 USTPUTC(' ',out); 1849 } 1850 goto parsearith_return; 1851 } 1852 1853 } /* end of readtoken */ 1854 1855 1856 1857 #ifdef mkinit 1858 RESET { 1859 tokpushback = 0; 1860 checkkwd = 0; 1861 } 1862 #endif 1863 1864 /* 1865 * Returns true if the text contains nothing to expand (no dollar signs 1866 * or backquotes). 1867 */ 1868 1869 STATIC int 1870 noexpand(char *text) 1871 { 1872 char *p; 1873 char c; 1874 1875 p = text; 1876 while ((c = *p++) != '\0') { 1877 if (c == CTLQUOTEMARK) 1878 continue; 1879 if (c == CTLESC) 1880 p++; 1881 else if (BASESYNTAX[(int)c] == CCTL) 1882 return 0; 1883 } 1884 return 1; 1885 } 1886 1887 1888 /* 1889 * Return true if the argument is a legal variable name (a letter or 1890 * underscore followed by zero or more letters, underscores, and digits). 1891 */ 1892 1893 int 1894 goodname(char *name) 1895 { 1896 char *p; 1897 1898 p = name; 1899 if (! is_name(*p)) 1900 return 0; 1901 while (*++p) { 1902 if (! is_in_name(*p)) 1903 return 0; 1904 } 1905 return 1; 1906 } 1907 1908 1909 /* 1910 * Called when an unexpected token is read during the parse. The argument 1911 * is the token that is expected, or -1 if more than one type of token can 1912 * occur at this point. 1913 */ 1914 1915 STATIC void 1916 synexpect(int token, const char *text) 1917 { 1918 char msg[64]; 1919 char *p; 1920 1921 if (lasttoken == TWORD) { 1922 size_t len = strlen(wordtext); 1923 1924 if (len <= 13) 1925 fmtstr(msg, 34, "Word \"%.13s\" unexpected", wordtext); 1926 else 1927 fmtstr(msg, 34, 1928 "Word \"%.10s...\" unexpected", wordtext); 1929 } else 1930 fmtstr(msg, 34, "%s unexpected", tokname[lasttoken]); 1931 1932 p = strchr(msg, '\0'); 1933 if (text) 1934 fmtstr(p, 30, " (expecting \"%.10s\")", text); 1935 else if (token >= 0) 1936 fmtstr(p, 30, " (expecting %s)", tokname[token]); 1937 1938 synerror(msg); 1939 /* NOTREACHED */ 1940 } 1941 1942 1943 STATIC void 1944 synerror(const char *msg) 1945 { 1946 error("%d: Syntax error: %s\n", startlinno, msg); 1947 /* NOTREACHED */ 1948 } 1949 1950 STATIC void 1951 setprompt(int which) 1952 { 1953 whichprompt = which; 1954 1955 #ifndef SMALL 1956 if (!el) 1957 #endif 1958 out2str(getprompt(NULL)); 1959 } 1960 1961 /* 1962 * called by editline -- any expansions to the prompt 1963 * should be added here. 1964 */ 1965 const char * 1966 getprompt(void *unused) 1967 { 1968 switch (whichprompt) { 1969 case 0: 1970 return ""; 1971 case 1: 1972 return ps1val(); 1973 case 2: 1974 return ps2val(); 1975 default: 1976 return "<internal prompt error>"; 1977 } 1978 } 1979