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 #include "exec.h" /* to check for special builtins */ 61 #ifndef NO_HISTORY 62 #include "myhistedit.h" 63 #endif 64 65 /* 66 * Shell command parser. 67 */ 68 69 #define EOFMARKLEN 79 70 #define PROMPTLEN 128 71 72 /* values of checkkwd variable */ 73 #define CHKALIAS 0x1 74 #define CHKKWD 0x2 75 #define CHKNL 0x4 76 77 /* values returned by readtoken */ 78 #include "token.h" 79 80 81 82 struct heredoc { 83 struct heredoc *next; /* next here document in list */ 84 union node *here; /* redirection node */ 85 char *eofmark; /* string indicating end of input */ 86 int striptabs; /* if set, strip leading tabs */ 87 }; 88 89 struct parser_temp { 90 struct parser_temp *next; 91 void *data; 92 }; 93 94 95 static struct heredoc *heredoclist; /* list of here documents to read */ 96 static int doprompt; /* if set, prompt the user */ 97 static int needprompt; /* true if interactive and at start of line */ 98 static int lasttoken; /* last token read */ 99 MKINIT int tokpushback; /* last token pushed back */ 100 static char *wordtext; /* text of last word returned by readtoken */ 101 MKINIT int checkkwd; /* 1 == check for kwds, 2 == also eat newlines */ 102 static struct nodelist *backquotelist; 103 static union node *redirnode; 104 static struct heredoc *heredoc; 105 static int quoteflag; /* set if (part of) last token was quoted */ 106 static int startlinno; /* line # where last token started */ 107 static int funclinno; /* line # where the current function started */ 108 static struct parser_temp *parser_temp; 109 110 111 static union node *list(int, int); 112 static union node *andor(void); 113 static union node *pipeline(void); 114 static union node *command(void); 115 static union node *simplecmd(union node **, union node *); 116 static union node *makename(void); 117 static void parsefname(void); 118 static void parseheredoc(void); 119 static int peektoken(void); 120 static int readtoken(void); 121 static int xxreadtoken(void); 122 static int readtoken1(int, char const *, char *, int); 123 static int noexpand(char *); 124 static void synexpect(int) __dead2; 125 static void synerror(const char *) __dead2; 126 static void setprompt(int); 127 128 129 static void * 130 parser_temp_alloc(size_t len) 131 { 132 struct parser_temp *t; 133 134 INTOFF; 135 t = ckmalloc(sizeof(*t)); 136 t->data = NULL; 137 t->next = parser_temp; 138 parser_temp = t; 139 t->data = ckmalloc(len); 140 INTON; 141 return t->data; 142 } 143 144 145 static void * 146 parser_temp_realloc(void *ptr, size_t len) 147 { 148 struct parser_temp *t; 149 150 INTOFF; 151 t = parser_temp; 152 if (ptr != t->data) 153 error("bug: parser_temp_realloc misused"); 154 t->data = ckrealloc(t->data, len); 155 INTON; 156 return t->data; 157 } 158 159 160 static void 161 parser_temp_free_upto(void *ptr) 162 { 163 struct parser_temp *t; 164 int done = 0; 165 166 INTOFF; 167 while (parser_temp != NULL && !done) { 168 t = parser_temp; 169 parser_temp = t->next; 170 done = t->data == ptr; 171 ckfree(t->data); 172 ckfree(t); 173 } 174 INTON; 175 if (!done) 176 error("bug: parser_temp_free_upto misused"); 177 } 178 179 180 static void 181 parser_temp_free_all(void) 182 { 183 struct parser_temp *t; 184 185 INTOFF; 186 while (parser_temp != NULL) { 187 t = parser_temp; 188 parser_temp = t->next; 189 ckfree(t->data); 190 ckfree(t); 191 } 192 INTON; 193 } 194 195 196 /* 197 * Read and parse a command. Returns NEOF on end of file. (NULL is a 198 * valid parse tree indicating a blank line.) 199 */ 200 201 union node * 202 parsecmd(int interact) 203 { 204 int t; 205 206 /* This assumes the parser is not re-entered, 207 * which could happen if we add command substitution on PS1/PS2. 208 */ 209 parser_temp_free_all(); 210 heredoclist = NULL; 211 212 tokpushback = 0; 213 doprompt = interact; 214 if (doprompt) 215 setprompt(1); 216 else 217 setprompt(0); 218 needprompt = 0; 219 t = readtoken(); 220 if (t == TEOF) 221 return NEOF; 222 if (t == TNL) 223 return NULL; 224 tokpushback++; 225 return list(1, 1); 226 } 227 228 229 static union node * 230 list(int nlflag, int erflag) 231 { 232 union node *ntop, *n1, *n2, *n3; 233 int tok; 234 235 checkkwd = CHKNL | CHKKWD | CHKALIAS; 236 if (!nlflag && !erflag && tokendlist[peektoken()]) 237 return NULL; 238 ntop = n1 = NULL; 239 for (;;) { 240 n2 = andor(); 241 tok = readtoken(); 242 if (tok == TBACKGND) { 243 if (n2->type == NCMD || n2->type == NPIPE) { 244 n2->ncmd.backgnd = 1; 245 } else if (n2->type == NREDIR) { 246 n2->type = NBACKGND; 247 } else { 248 n3 = (union node *)stalloc(sizeof (struct nredir)); 249 n3->type = NBACKGND; 250 n3->nredir.n = n2; 251 n3->nredir.redirect = NULL; 252 n2 = n3; 253 } 254 } 255 if (ntop == NULL) 256 ntop = n2; 257 else if (n1 == NULL) { 258 n1 = (union node *)stalloc(sizeof (struct nbinary)); 259 n1->type = NSEMI; 260 n1->nbinary.ch1 = ntop; 261 n1->nbinary.ch2 = n2; 262 ntop = n1; 263 } 264 else { 265 n3 = (union node *)stalloc(sizeof (struct nbinary)); 266 n3->type = NSEMI; 267 n3->nbinary.ch1 = n1->nbinary.ch2; 268 n3->nbinary.ch2 = n2; 269 n1->nbinary.ch2 = n3; 270 n1 = n3; 271 } 272 switch (tok) { 273 case TBACKGND: 274 case TSEMI: 275 tok = readtoken(); 276 /* FALLTHROUGH */ 277 case TNL: 278 if (tok == TNL) { 279 parseheredoc(); 280 if (nlflag) 281 return ntop; 282 } else if (tok == TEOF && nlflag) { 283 parseheredoc(); 284 return ntop; 285 } else { 286 tokpushback++; 287 } 288 checkkwd = CHKNL | CHKKWD | CHKALIAS; 289 if (!nlflag && !erflag && tokendlist[peektoken()]) 290 return ntop; 291 break; 292 case TEOF: 293 if (heredoclist) 294 parseheredoc(); 295 else 296 pungetc(); /* push back EOF on input */ 297 return ntop; 298 default: 299 if (nlflag || erflag) 300 synexpect(-1); 301 tokpushback++; 302 return ntop; 303 } 304 } 305 } 306 307 308 309 static union node * 310 andor(void) 311 { 312 union node *n1, *n2, *n3; 313 int t; 314 315 n1 = pipeline(); 316 for (;;) { 317 if ((t = readtoken()) == TAND) { 318 t = NAND; 319 } else if (t == TOR) { 320 t = NOR; 321 } else { 322 tokpushback++; 323 return n1; 324 } 325 n2 = pipeline(); 326 n3 = (union node *)stalloc(sizeof (struct nbinary)); 327 n3->type = t; 328 n3->nbinary.ch1 = n1; 329 n3->nbinary.ch2 = n2; 330 n1 = n3; 331 } 332 } 333 334 335 336 static union node * 337 pipeline(void) 338 { 339 union node *n1, *n2, *pipenode; 340 struct nodelist *lp, *prev; 341 int negate, t; 342 343 negate = 0; 344 checkkwd = CHKNL | CHKKWD | CHKALIAS; 345 TRACE(("pipeline: entered\n")); 346 while (readtoken() == TNOT) 347 negate = !negate; 348 tokpushback++; 349 n1 = command(); 350 if (readtoken() == TPIPE) { 351 pipenode = (union node *)stalloc(sizeof (struct npipe)); 352 pipenode->type = NPIPE; 353 pipenode->npipe.backgnd = 0; 354 lp = (struct nodelist *)stalloc(sizeof (struct nodelist)); 355 pipenode->npipe.cmdlist = lp; 356 lp->n = n1; 357 do { 358 prev = lp; 359 lp = (struct nodelist *)stalloc(sizeof (struct nodelist)); 360 checkkwd = CHKNL | CHKKWD | CHKALIAS; 361 t = readtoken(); 362 tokpushback++; 363 if (t == TNOT) 364 lp->n = pipeline(); 365 else 366 lp->n = command(); 367 prev->next = lp; 368 } while (readtoken() == TPIPE); 369 lp->next = NULL; 370 n1 = pipenode; 371 } 372 tokpushback++; 373 if (negate) { 374 n2 = (union node *)stalloc(sizeof (struct nnot)); 375 n2->type = NNOT; 376 n2->nnot.com = n1; 377 return n2; 378 } else 379 return n1; 380 } 381 382 383 384 static union node * 385 command(void) 386 { 387 union node *n1, *n2; 388 union node *ap, **app; 389 union node *cp, **cpp; 390 union node *redir, **rpp; 391 int t; 392 int is_subshell; 393 394 checkkwd = CHKNL | CHKKWD | CHKALIAS; 395 is_subshell = 0; 396 redir = NULL; 397 n1 = NULL; 398 rpp = &redir; 399 400 /* Check for redirection which may precede command */ 401 while (readtoken() == TREDIR) { 402 *rpp = n2 = redirnode; 403 rpp = &n2->nfile.next; 404 parsefname(); 405 } 406 tokpushback++; 407 408 switch (readtoken()) { 409 case TIF: 410 n1 = (union node *)stalloc(sizeof (struct nif)); 411 n1->type = NIF; 412 if ((n1->nif.test = list(0, 0)) == NULL) 413 synexpect(-1); 414 if (readtoken() != TTHEN) 415 synexpect(TTHEN); 416 n1->nif.ifpart = list(0, 0); 417 n2 = n1; 418 while (readtoken() == TELIF) { 419 n2->nif.elsepart = (union node *)stalloc(sizeof (struct nif)); 420 n2 = n2->nif.elsepart; 421 n2->type = NIF; 422 if ((n2->nif.test = list(0, 0)) == NULL) 423 synexpect(-1); 424 if (readtoken() != TTHEN) 425 synexpect(TTHEN); 426 n2->nif.ifpart = list(0, 0); 427 } 428 if (lasttoken == TELSE) 429 n2->nif.elsepart = list(0, 0); 430 else { 431 n2->nif.elsepart = NULL; 432 tokpushback++; 433 } 434 if (readtoken() != TFI) 435 synexpect(TFI); 436 checkkwd = CHKKWD | CHKALIAS; 437 break; 438 case TWHILE: 439 case TUNTIL: { 440 int got; 441 n1 = (union node *)stalloc(sizeof (struct nbinary)); 442 n1->type = (lasttoken == TWHILE)? NWHILE : NUNTIL; 443 if ((n1->nbinary.ch1 = list(0, 0)) == NULL) 444 synexpect(-1); 445 if ((got=readtoken()) != TDO) { 446 TRACE(("expecting DO got %s %s\n", tokname[got], got == TWORD ? wordtext : "")); 447 synexpect(TDO); 448 } 449 n1->nbinary.ch2 = list(0, 0); 450 if (readtoken() != TDONE) 451 synexpect(TDONE); 452 checkkwd = CHKKWD | CHKALIAS; 453 break; 454 } 455 case TFOR: 456 if (readtoken() != TWORD || quoteflag || ! goodname(wordtext)) 457 synerror("Bad for loop variable"); 458 n1 = (union node *)stalloc(sizeof (struct nfor)); 459 n1->type = NFOR; 460 n1->nfor.var = wordtext; 461 while (readtoken() == TNL) 462 ; 463 if (lasttoken == TWORD && ! quoteflag && equal(wordtext, "in")) { 464 app = ≈ 465 while (readtoken() == TWORD) { 466 n2 = (union node *)stalloc(sizeof (struct narg)); 467 n2->type = NARG; 468 n2->narg.text = wordtext; 469 n2->narg.backquote = backquotelist; 470 *app = n2; 471 app = &n2->narg.next; 472 } 473 *app = NULL; 474 n1->nfor.args = ap; 475 if (lasttoken != TNL && lasttoken != TSEMI) 476 synexpect(-1); 477 } else { 478 static char argvars[5] = { 479 CTLVAR, VSNORMAL|VSQUOTE, '@', '=', '\0' 480 }; 481 n2 = (union node *)stalloc(sizeof (struct narg)); 482 n2->type = NARG; 483 n2->narg.text = argvars; 484 n2->narg.backquote = NULL; 485 n2->narg.next = NULL; 486 n1->nfor.args = n2; 487 /* 488 * Newline or semicolon here is optional (but note 489 * that the original Bourne shell only allowed NL). 490 */ 491 if (lasttoken != TNL && lasttoken != TSEMI) 492 tokpushback++; 493 } 494 checkkwd = CHKNL | CHKKWD | CHKALIAS; 495 if ((t = readtoken()) == TDO) 496 t = TDONE; 497 else if (t == TBEGIN) 498 t = TEND; 499 else 500 synexpect(-1); 501 n1->nfor.body = list(0, 0); 502 if (readtoken() != t) 503 synexpect(t); 504 checkkwd = CHKKWD | CHKALIAS; 505 break; 506 case TCASE: 507 n1 = (union node *)stalloc(sizeof (struct ncase)); 508 n1->type = NCASE; 509 if (readtoken() != TWORD) 510 synexpect(TWORD); 511 n1->ncase.expr = n2 = (union node *)stalloc(sizeof (struct narg)); 512 n2->type = NARG; 513 n2->narg.text = wordtext; 514 n2->narg.backquote = backquotelist; 515 n2->narg.next = NULL; 516 while (readtoken() == TNL); 517 if (lasttoken != TWORD || ! equal(wordtext, "in")) 518 synerror("expecting \"in\""); 519 cpp = &n1->ncase.cases; 520 checkkwd = CHKNL | CHKKWD, readtoken(); 521 while (lasttoken != TESAC) { 522 *cpp = cp = (union node *)stalloc(sizeof (struct nclist)); 523 cp->type = NCLIST; 524 app = &cp->nclist.pattern; 525 if (lasttoken == TLP) 526 readtoken(); 527 for (;;) { 528 *app = ap = (union node *)stalloc(sizeof (struct narg)); 529 ap->type = NARG; 530 ap->narg.text = wordtext; 531 ap->narg.backquote = backquotelist; 532 checkkwd = CHKNL | CHKKWD; 533 if (readtoken() != TPIPE) 534 break; 535 app = &ap->narg.next; 536 readtoken(); 537 } 538 ap->narg.next = NULL; 539 if (lasttoken != TRP) 540 synexpect(TRP); 541 cp->nclist.body = list(0, 0); 542 543 checkkwd = CHKNL | CHKKWD | CHKALIAS; 544 if ((t = readtoken()) != TESAC) { 545 if (t != TENDCASE) 546 synexpect(TENDCASE); 547 else 548 checkkwd = CHKNL | CHKKWD, readtoken(); 549 } 550 cpp = &cp->nclist.next; 551 } 552 *cpp = NULL; 553 checkkwd = CHKKWD | CHKALIAS; 554 break; 555 case TLP: 556 n1 = (union node *)stalloc(sizeof (struct nredir)); 557 n1->type = NSUBSHELL; 558 n1->nredir.n = list(0, 0); 559 n1->nredir.redirect = NULL; 560 if (readtoken() != TRP) 561 synexpect(TRP); 562 checkkwd = CHKKWD | CHKALIAS; 563 is_subshell = 1; 564 break; 565 case TBEGIN: 566 n1 = list(0, 0); 567 if (readtoken() != TEND) 568 synexpect(TEND); 569 checkkwd = CHKKWD | CHKALIAS; 570 break; 571 /* Handle an empty command like other simple commands. */ 572 case TBACKGND: 573 case TSEMI: 574 case TAND: 575 case TOR: 576 /* 577 * An empty command before a ; doesn't make much sense, and 578 * should certainly be disallowed in the case of `if ;'. 579 */ 580 if (!redir) 581 synexpect(-1); 582 case TNL: 583 case TEOF: 584 case TWORD: 585 case TRP: 586 tokpushback++; 587 n1 = simplecmd(rpp, redir); 588 return n1; 589 default: 590 synexpect(-1); 591 } 592 593 /* Now check for redirection which may follow command */ 594 while (readtoken() == TREDIR) { 595 *rpp = n2 = redirnode; 596 rpp = &n2->nfile.next; 597 parsefname(); 598 } 599 tokpushback++; 600 *rpp = NULL; 601 if (redir) { 602 if (!is_subshell) { 603 n2 = (union node *)stalloc(sizeof (struct nredir)); 604 n2->type = NREDIR; 605 n2->nredir.n = n1; 606 n1 = n2; 607 } 608 n1->nredir.redirect = redir; 609 } 610 611 return n1; 612 } 613 614 615 static union node * 616 simplecmd(union node **rpp, union node *redir) 617 { 618 union node *args, **app; 619 union node **orig_rpp = rpp; 620 union node *n = NULL; 621 int special; 622 int savecheckkwd; 623 624 /* If we don't have any redirections already, then we must reset */ 625 /* rpp to be the address of the local redir variable. */ 626 if (redir == 0) 627 rpp = &redir; 628 629 args = NULL; 630 app = &args; 631 /* 632 * We save the incoming value, because we need this for shell 633 * functions. There can not be a redirect or an argument between 634 * the function name and the open parenthesis. 635 */ 636 orig_rpp = rpp; 637 638 savecheckkwd = CHKALIAS; 639 640 for (;;) { 641 checkkwd = savecheckkwd; 642 if (readtoken() == TWORD) { 643 n = (union node *)stalloc(sizeof (struct narg)); 644 n->type = NARG; 645 n->narg.text = wordtext; 646 n->narg.backquote = backquotelist; 647 *app = n; 648 app = &n->narg.next; 649 if (savecheckkwd != 0 && !isassignment(wordtext)) 650 savecheckkwd = 0; 651 } else if (lasttoken == TREDIR) { 652 *rpp = n = redirnode; 653 rpp = &n->nfile.next; 654 parsefname(); /* read name of redirection file */ 655 } else if (lasttoken == TLP && app == &args->narg.next 656 && rpp == orig_rpp) { 657 /* We have a function */ 658 if (readtoken() != TRP) 659 synexpect(TRP); 660 funclinno = plinno; 661 /* 662 * - Require plain text. 663 * - Functions with '/' cannot be called. 664 * - Reject name=(). 665 * - Reject ksh extended glob patterns. 666 */ 667 if (!noexpand(n->narg.text) || quoteflag || 668 strchr(n->narg.text, '/') || 669 strchr("!%*+-=?@}~", 670 n->narg.text[strlen(n->narg.text) - 1])) 671 synerror("Bad function name"); 672 rmescapes(n->narg.text); 673 if (find_builtin(n->narg.text, &special) >= 0 && 674 special) 675 synerror("Cannot override a special builtin with a function"); 676 n->type = NDEFUN; 677 n->narg.next = command(); 678 funclinno = 0; 679 return n; 680 } else { 681 tokpushback++; 682 break; 683 } 684 } 685 *app = NULL; 686 *rpp = NULL; 687 n = (union node *)stalloc(sizeof (struct ncmd)); 688 n->type = NCMD; 689 n->ncmd.backgnd = 0; 690 n->ncmd.args = args; 691 n->ncmd.redirect = redir; 692 return n; 693 } 694 695 static union node * 696 makename(void) 697 { 698 union node *n; 699 700 n = (union node *)stalloc(sizeof (struct narg)); 701 n->type = NARG; 702 n->narg.next = NULL; 703 n->narg.text = wordtext; 704 n->narg.backquote = backquotelist; 705 return n; 706 } 707 708 void 709 fixredir(union node *n, const char *text, int err) 710 { 711 TRACE(("Fix redir %s %d\n", text, err)); 712 if (!err) 713 n->ndup.vname = NULL; 714 715 if (is_digit(text[0]) && text[1] == '\0') 716 n->ndup.dupfd = digit_val(text[0]); 717 else if (text[0] == '-' && text[1] == '\0') 718 n->ndup.dupfd = -1; 719 else { 720 721 if (err) 722 synerror("Bad fd number"); 723 else 724 n->ndup.vname = makename(); 725 } 726 } 727 728 729 static void 730 parsefname(void) 731 { 732 union node *n = redirnode; 733 734 if (readtoken() != TWORD) 735 synexpect(-1); 736 if (n->type == NHERE) { 737 struct heredoc *here = heredoc; 738 struct heredoc *p; 739 int i; 740 741 if (quoteflag == 0) 742 n->type = NXHERE; 743 TRACE(("Here document %d\n", n->type)); 744 if (here->striptabs) { 745 while (*wordtext == '\t') 746 wordtext++; 747 } 748 if (! noexpand(wordtext) || (i = strlen(wordtext)) == 0 || i > EOFMARKLEN) 749 synerror("Illegal eof marker for << redirection"); 750 rmescapes(wordtext); 751 here->eofmark = wordtext; 752 here->next = NULL; 753 if (heredoclist == NULL) 754 heredoclist = here; 755 else { 756 for (p = heredoclist ; p->next ; p = p->next); 757 p->next = here; 758 } 759 } else if (n->type == NTOFD || n->type == NFROMFD) { 760 fixredir(n, wordtext, 0); 761 } else { 762 n->nfile.fname = makename(); 763 } 764 } 765 766 767 /* 768 * Input any here documents. 769 */ 770 771 static void 772 parseheredoc(void) 773 { 774 struct heredoc *here; 775 union node *n; 776 777 while (heredoclist) { 778 here = heredoclist; 779 heredoclist = here->next; 780 if (needprompt) { 781 setprompt(2); 782 needprompt = 0; 783 } 784 readtoken1(pgetc(), here->here->type == NHERE? SQSYNTAX : DQSYNTAX, 785 here->eofmark, here->striptabs); 786 n = (union node *)stalloc(sizeof (struct narg)); 787 n->narg.type = NARG; 788 n->narg.next = NULL; 789 n->narg.text = wordtext; 790 n->narg.backquote = backquotelist; 791 here->here->nhere.doc = n; 792 } 793 } 794 795 static int 796 peektoken(void) 797 { 798 int t; 799 800 t = readtoken(); 801 tokpushback++; 802 return (t); 803 } 804 805 static int 806 readtoken(void) 807 { 808 int t; 809 struct alias *ap; 810 #ifdef DEBUG 811 int alreadyseen = tokpushback; 812 #endif 813 814 top: 815 t = xxreadtoken(); 816 817 /* 818 * eat newlines 819 */ 820 if (checkkwd & CHKNL) { 821 while (t == TNL) { 822 parseheredoc(); 823 t = xxreadtoken(); 824 } 825 } 826 827 /* 828 * check for keywords and aliases 829 */ 830 if (t == TWORD && !quoteflag) 831 { 832 const char * const *pp; 833 834 if (checkkwd & CHKKWD) 835 for (pp = parsekwd; *pp; pp++) { 836 if (**pp == *wordtext && equal(*pp, wordtext)) 837 { 838 lasttoken = t = pp - parsekwd + KWDOFFSET; 839 TRACE(("keyword %s recognized\n", tokname[t])); 840 goto out; 841 } 842 } 843 if (checkkwd & CHKALIAS && 844 (ap = lookupalias(wordtext, 1)) != NULL) { 845 pushstring(ap->val, strlen(ap->val), ap); 846 goto top; 847 } 848 } 849 out: 850 if (t != TNOT) 851 checkkwd = 0; 852 853 #ifdef DEBUG 854 if (!alreadyseen) 855 TRACE(("token %s %s\n", tokname[t], t == TWORD ? wordtext : "")); 856 else 857 TRACE(("reread token %s %s\n", tokname[t], t == TWORD ? wordtext : "")); 858 #endif 859 return (t); 860 } 861 862 863 /* 864 * Read the next input token. 865 * If the token is a word, we set backquotelist to the list of cmds in 866 * backquotes. We set quoteflag to true if any part of the word was 867 * quoted. 868 * If the token is TREDIR, then we set redirnode to a structure containing 869 * the redirection. 870 * In all cases, the variable startlinno is set to the number of the line 871 * on which the token starts. 872 * 873 * [Change comment: here documents and internal procedures] 874 * [Readtoken shouldn't have any arguments. Perhaps we should make the 875 * word parsing code into a separate routine. In this case, readtoken 876 * doesn't need to have any internal procedures, but parseword does. 877 * We could also make parseoperator in essence the main routine, and 878 * have parseword (readtoken1?) handle both words and redirection.] 879 */ 880 881 #define RETURN(token) return lasttoken = token 882 883 static int 884 xxreadtoken(void) 885 { 886 int c; 887 888 if (tokpushback) { 889 tokpushback = 0; 890 return lasttoken; 891 } 892 if (needprompt) { 893 setprompt(2); 894 needprompt = 0; 895 } 896 startlinno = plinno; 897 for (;;) { /* until token or start of word found */ 898 c = pgetc_macro(); 899 switch (c) { 900 case ' ': case '\t': 901 continue; 902 case '#': 903 while ((c = pgetc()) != '\n' && c != PEOF); 904 pungetc(); 905 continue; 906 case '\\': 907 if (pgetc() == '\n') { 908 startlinno = ++plinno; 909 if (doprompt) 910 setprompt(2); 911 else 912 setprompt(0); 913 continue; 914 } 915 pungetc(); 916 goto breakloop; 917 case '\n': 918 plinno++; 919 needprompt = doprompt; 920 RETURN(TNL); 921 case PEOF: 922 RETURN(TEOF); 923 case '&': 924 if (pgetc() == '&') 925 RETURN(TAND); 926 pungetc(); 927 RETURN(TBACKGND); 928 case '|': 929 if (pgetc() == '|') 930 RETURN(TOR); 931 pungetc(); 932 RETURN(TPIPE); 933 case ';': 934 if (pgetc() == ';') 935 RETURN(TENDCASE); 936 pungetc(); 937 RETURN(TSEMI); 938 case '(': 939 RETURN(TLP); 940 case ')': 941 RETURN(TRP); 942 default: 943 goto breakloop; 944 } 945 } 946 breakloop: 947 return readtoken1(c, BASESYNTAX, (char *)NULL, 0); 948 #undef RETURN 949 } 950 951 952 #define MAXNEST_static 8 953 struct tokenstate 954 { 955 const char *syntax; /* *SYNTAX */ 956 int parenlevel; /* levels of parentheses in arithmetic */ 957 enum tokenstate_category 958 { 959 TSTATE_TOP, 960 TSTATE_VAR_OLD, /* ${var+-=?}, inherits dquotes */ 961 TSTATE_VAR_NEW, /* other ${var...}, own dquote state */ 962 TSTATE_ARITH 963 } category; 964 }; 965 966 967 /* 968 * Called to parse command substitutions. 969 */ 970 971 static char * 972 parsebackq(char *out, struct nodelist **pbqlist, 973 int oldstyle, int dblquote, int quoted) 974 { 975 struct nodelist **nlpp; 976 union node *n; 977 char *volatile str; 978 struct jmploc jmploc; 979 struct jmploc *const savehandler = handler; 980 int savelen; 981 int saveprompt; 982 const int bq_startlinno = plinno; 983 char *volatile ostr = NULL; 984 struct parsefile *const savetopfile = getcurrentfile(); 985 struct heredoc *const saveheredoclist = heredoclist; 986 struct heredoc *here; 987 988 str = NULL; 989 if (setjmp(jmploc.loc)) { 990 popfilesupto(savetopfile); 991 if (str) 992 ckfree(str); 993 if (ostr) 994 ckfree(ostr); 995 heredoclist = saveheredoclist; 996 handler = savehandler; 997 if (exception == EXERROR) { 998 startlinno = bq_startlinno; 999 synerror("Error in command substitution"); 1000 } 1001 longjmp(handler->loc, 1); 1002 } 1003 INTOFF; 1004 savelen = out - stackblock(); 1005 if (savelen > 0) { 1006 str = ckmalloc(savelen); 1007 memcpy(str, stackblock(), savelen); 1008 } 1009 handler = &jmploc; 1010 heredoclist = NULL; 1011 INTON; 1012 if (oldstyle) { 1013 /* We must read until the closing backquote, giving special 1014 treatment to some slashes, and then push the string and 1015 reread it as input, interpreting it normally. */ 1016 char *oout; 1017 int c; 1018 int olen; 1019 1020 1021 STARTSTACKSTR(oout); 1022 for (;;) { 1023 if (needprompt) { 1024 setprompt(2); 1025 needprompt = 0; 1026 } 1027 CHECKSTRSPACE(2, oout); 1028 switch (c = pgetc()) { 1029 case '`': 1030 goto done; 1031 1032 case '\\': 1033 if ((c = pgetc()) == '\n') { 1034 plinno++; 1035 if (doprompt) 1036 setprompt(2); 1037 else 1038 setprompt(0); 1039 /* 1040 * If eating a newline, avoid putting 1041 * the newline into the new character 1042 * stream (via the USTPUTC after the 1043 * switch). 1044 */ 1045 continue; 1046 } 1047 if (c != '\\' && c != '`' && c != '$' 1048 && (!dblquote || c != '"')) 1049 USTPUTC('\\', oout); 1050 break; 1051 1052 case '\n': 1053 plinno++; 1054 needprompt = doprompt; 1055 break; 1056 1057 case PEOF: 1058 startlinno = plinno; 1059 synerror("EOF in backquote substitution"); 1060 break; 1061 1062 default: 1063 break; 1064 } 1065 USTPUTC(c, oout); 1066 } 1067 done: 1068 USTPUTC('\0', oout); 1069 olen = oout - stackblock(); 1070 INTOFF; 1071 ostr = ckmalloc(olen); 1072 memcpy(ostr, stackblock(), olen); 1073 setinputstring(ostr, 1); 1074 INTON; 1075 } 1076 nlpp = pbqlist; 1077 while (*nlpp) 1078 nlpp = &(*nlpp)->next; 1079 *nlpp = (struct nodelist *)stalloc(sizeof (struct nodelist)); 1080 (*nlpp)->next = NULL; 1081 1082 if (oldstyle) { 1083 saveprompt = doprompt; 1084 doprompt = 0; 1085 } 1086 1087 n = list(0, oldstyle); 1088 1089 if (oldstyle) 1090 doprompt = saveprompt; 1091 else { 1092 if (readtoken() != TRP) 1093 synexpect(TRP); 1094 } 1095 1096 (*nlpp)->n = n; 1097 if (oldstyle) { 1098 /* 1099 * Start reading from old file again, ignoring any pushed back 1100 * tokens left from the backquote parsing 1101 */ 1102 popfile(); 1103 tokpushback = 0; 1104 } 1105 STARTSTACKSTR(out); 1106 CHECKSTRSPACE(savelen + 1, out); 1107 INTOFF; 1108 if (str) { 1109 memcpy(out, str, savelen); 1110 STADJUST(savelen, out); 1111 ckfree(str); 1112 str = NULL; 1113 } 1114 if (ostr) { 1115 ckfree(ostr); 1116 ostr = NULL; 1117 } 1118 here = saveheredoclist; 1119 if (here != NULL) { 1120 while (here->next != NULL) 1121 here = here->next; 1122 here->next = heredoclist; 1123 heredoclist = saveheredoclist; 1124 } 1125 handler = savehandler; 1126 INTON; 1127 if (quoted) 1128 USTPUTC(CTLBACKQ | CTLQUOTE, out); 1129 else 1130 USTPUTC(CTLBACKQ, out); 1131 return out; 1132 } 1133 1134 1135 /* 1136 * Called to parse a backslash escape sequence inside $'...'. 1137 * The backslash has already been read. 1138 */ 1139 static char * 1140 readcstyleesc(char *out) 1141 { 1142 int c, v, i, n; 1143 1144 c = pgetc(); 1145 switch (c) { 1146 case '\0': 1147 synerror("Unterminated quoted string"); 1148 case '\n': 1149 plinno++; 1150 if (doprompt) 1151 setprompt(2); 1152 else 1153 setprompt(0); 1154 return out; 1155 case '\\': 1156 case '\'': 1157 case '"': 1158 v = c; 1159 break; 1160 case 'a': v = '\a'; break; 1161 case 'b': v = '\b'; break; 1162 case 'e': v = '\033'; break; 1163 case 'f': v = '\f'; break; 1164 case 'n': v = '\n'; break; 1165 case 'r': v = '\r'; break; 1166 case 't': v = '\t'; break; 1167 case 'v': v = '\v'; break; 1168 case 'x': 1169 v = 0; 1170 for (;;) { 1171 c = pgetc(); 1172 if (c >= '0' && c <= '9') 1173 v = (v << 4) + c - '0'; 1174 else if (c >= 'A' && c <= 'F') 1175 v = (v << 4) + c - 'A' + 10; 1176 else if (c >= 'a' && c <= 'f') 1177 v = (v << 4) + c - 'a' + 10; 1178 else 1179 break; 1180 } 1181 pungetc(); 1182 break; 1183 case '0': case '1': case '2': case '3': 1184 case '4': case '5': case '6': case '7': 1185 v = c - '0'; 1186 c = pgetc(); 1187 if (c >= '0' && c <= '7') { 1188 v <<= 3; 1189 v += c - '0'; 1190 c = pgetc(); 1191 if (c >= '0' && c <= '7') { 1192 v <<= 3; 1193 v += c - '0'; 1194 } else 1195 pungetc(); 1196 } else 1197 pungetc(); 1198 break; 1199 case 'c': 1200 c = pgetc(); 1201 if (c < 0x3f || c > 0x7a || c == 0x60) 1202 synerror("Bad escape sequence"); 1203 if (c == '\\' && pgetc() != '\\') 1204 synerror("Bad escape sequence"); 1205 if (c == '?') 1206 v = 127; 1207 else 1208 v = c & 0x1f; 1209 break; 1210 case 'u': 1211 case 'U': 1212 n = c == 'U' ? 8 : 4; 1213 v = 0; 1214 for (i = 0; i < n; i++) { 1215 c = pgetc(); 1216 if (c >= '0' && c <= '9') 1217 v = (v << 4) + c - '0'; 1218 else if (c >= 'A' && c <= 'F') 1219 v = (v << 4) + c - 'A' + 10; 1220 else if (c >= 'a' && c <= 'f') 1221 v = (v << 4) + c - 'a' + 10; 1222 else 1223 synerror("Bad escape sequence"); 1224 } 1225 if (v == 0 || (v >= 0xd800 && v <= 0xdfff)) 1226 synerror("Bad escape sequence"); 1227 /* We really need iconv here. */ 1228 if (initial_localeisutf8 && v > 127) { 1229 CHECKSTRSPACE(4, out); 1230 /* 1231 * We cannot use wctomb() as the locale may have 1232 * changed. 1233 */ 1234 if (v <= 0x7ff) { 1235 USTPUTC(0xc0 | v >> 6, out); 1236 USTPUTC(0x80 | (v & 0x3f), out); 1237 return out; 1238 } else if (v <= 0xffff) { 1239 USTPUTC(0xe0 | v >> 12, out); 1240 USTPUTC(0x80 | ((v >> 6) & 0x3f), out); 1241 USTPUTC(0x80 | (v & 0x3f), out); 1242 return out; 1243 } else if (v <= 0x10ffff) { 1244 USTPUTC(0xf0 | v >> 18, out); 1245 USTPUTC(0x80 | ((v >> 12) & 0x3f), out); 1246 USTPUTC(0x80 | ((v >> 6) & 0x3f), out); 1247 USTPUTC(0x80 | (v & 0x3f), out); 1248 return out; 1249 } 1250 } 1251 if (v > 127) 1252 v = '?'; 1253 break; 1254 default: 1255 synerror("Bad escape sequence"); 1256 } 1257 v = (char)v; 1258 /* 1259 * We can't handle NUL bytes. 1260 * POSIX says we should skip till the closing quote. 1261 */ 1262 if (v == '\0') { 1263 while ((c = pgetc()) != '\'') { 1264 if (c == '\\') 1265 c = pgetc(); 1266 if (c == PEOF) 1267 synerror("Unterminated quoted string"); 1268 } 1269 pungetc(); 1270 return out; 1271 } 1272 if (SQSYNTAX[v] == CCTL) 1273 USTPUTC(CTLESC, out); 1274 USTPUTC(v, out); 1275 return out; 1276 } 1277 1278 1279 /* 1280 * If eofmark is NULL, read a word or a redirection symbol. If eofmark 1281 * is not NULL, read a here document. In the latter case, eofmark is the 1282 * word which marks the end of the document and striptabs is true if 1283 * leading tabs should be stripped from the document. The argument firstc 1284 * is the first character of the input token or document. 1285 * 1286 * Because C does not have internal subroutines, I have simulated them 1287 * using goto's to implement the subroutine linkage. The following macros 1288 * will run code that appears at the end of readtoken1. 1289 */ 1290 1291 #define CHECKEND() {goto checkend; checkend_return:;} 1292 #define PARSEREDIR() {goto parseredir; parseredir_return:;} 1293 #define PARSESUB() {goto parsesub; parsesub_return:;} 1294 #define PARSEARITH() {goto parsearith; parsearith_return:;} 1295 1296 static int 1297 readtoken1(int firstc, char const *initialsyntax, char *eofmark, int striptabs) 1298 { 1299 int c = firstc; 1300 char *out; 1301 int len; 1302 char line[EOFMARKLEN + 1]; 1303 struct nodelist *bqlist; 1304 int quotef; 1305 int newvarnest; 1306 int level; 1307 int synentry; 1308 struct tokenstate state_static[MAXNEST_static]; 1309 int maxnest = MAXNEST_static; 1310 struct tokenstate *state = state_static; 1311 int sqiscstyle = 0; 1312 1313 startlinno = plinno; 1314 quotef = 0; 1315 bqlist = NULL; 1316 newvarnest = 0; 1317 level = 0; 1318 state[level].syntax = initialsyntax; 1319 state[level].parenlevel = 0; 1320 state[level].category = TSTATE_TOP; 1321 1322 STARTSTACKSTR(out); 1323 loop: { /* for each line, until end of word */ 1324 CHECKEND(); /* set c to PEOF if at end of here document */ 1325 for (;;) { /* until end of line or end of word */ 1326 CHECKSTRSPACE(4, out); /* permit 4 calls to USTPUTC */ 1327 1328 synentry = state[level].syntax[c]; 1329 1330 switch(synentry) { 1331 case CNL: /* '\n' */ 1332 if (state[level].syntax == BASESYNTAX) 1333 goto endword; /* exit outer loop */ 1334 USTPUTC(c, out); 1335 plinno++; 1336 if (doprompt) 1337 setprompt(2); 1338 else 1339 setprompt(0); 1340 c = pgetc(); 1341 goto loop; /* continue outer loop */ 1342 case CSBACK: 1343 if (sqiscstyle) { 1344 out = readcstyleesc(out); 1345 break; 1346 } 1347 /* FALLTHROUGH */ 1348 case CWORD: 1349 USTPUTC(c, out); 1350 break; 1351 case CCTL: 1352 if (eofmark == NULL || initialsyntax != SQSYNTAX) 1353 USTPUTC(CTLESC, out); 1354 USTPUTC(c, out); 1355 break; 1356 case CBACK: /* backslash */ 1357 c = pgetc(); 1358 if (c == PEOF) { 1359 USTPUTC('\\', out); 1360 pungetc(); 1361 } else if (c == '\n') { 1362 plinno++; 1363 if (doprompt) 1364 setprompt(2); 1365 else 1366 setprompt(0); 1367 } else { 1368 if (state[level].syntax == DQSYNTAX && 1369 c != '\\' && c != '`' && c != '$' && 1370 (c != '"' || (eofmark != NULL && 1371 newvarnest == 0)) && 1372 (c != '}' || state[level].category != TSTATE_VAR_OLD)) 1373 USTPUTC('\\', out); 1374 if ((eofmark == NULL || 1375 newvarnest > 0) && 1376 state[level].syntax == BASESYNTAX) 1377 USTPUTC(CTLQUOTEMARK, out); 1378 if (SQSYNTAX[c] == CCTL) 1379 USTPUTC(CTLESC, out); 1380 USTPUTC(c, out); 1381 if ((eofmark == NULL || 1382 newvarnest > 0) && 1383 state[level].syntax == BASESYNTAX && 1384 state[level].category == TSTATE_VAR_OLD) 1385 USTPUTC(CTLQUOTEEND, out); 1386 quotef++; 1387 } 1388 break; 1389 case CSQUOTE: 1390 USTPUTC(CTLQUOTEMARK, out); 1391 state[level].syntax = SQSYNTAX; 1392 sqiscstyle = 0; 1393 break; 1394 case CDQUOTE: 1395 USTPUTC(CTLQUOTEMARK, out); 1396 state[level].syntax = DQSYNTAX; 1397 break; 1398 case CENDQUOTE: 1399 if (eofmark != NULL && newvarnest == 0) 1400 USTPUTC(c, out); 1401 else { 1402 if (state[level].category == TSTATE_VAR_OLD) 1403 USTPUTC(CTLQUOTEEND, out); 1404 state[level].syntax = BASESYNTAX; 1405 quotef++; 1406 } 1407 break; 1408 case CVAR: /* '$' */ 1409 PARSESUB(); /* parse substitution */ 1410 break; 1411 case CENDVAR: /* '}' */ 1412 if (level > 0 && 1413 ((state[level].category == TSTATE_VAR_OLD && 1414 state[level].syntax == 1415 state[level - 1].syntax) || 1416 (state[level].category == TSTATE_VAR_NEW && 1417 state[level].syntax == BASESYNTAX))) { 1418 if (state[level].category == TSTATE_VAR_NEW) 1419 newvarnest--; 1420 level--; 1421 USTPUTC(CTLENDVAR, out); 1422 } else { 1423 USTPUTC(c, out); 1424 } 1425 break; 1426 case CLP: /* '(' in arithmetic */ 1427 state[level].parenlevel++; 1428 USTPUTC(c, out); 1429 break; 1430 case CRP: /* ')' in arithmetic */ 1431 if (state[level].parenlevel > 0) { 1432 USTPUTC(c, out); 1433 --state[level].parenlevel; 1434 } else { 1435 if (pgetc() == ')') { 1436 if (level > 0 && 1437 state[level].category == TSTATE_ARITH) { 1438 level--; 1439 USTPUTC(CTLENDARI, out); 1440 } else 1441 USTPUTC(')', out); 1442 } else { 1443 /* 1444 * unbalanced parens 1445 * (don't 2nd guess - no error) 1446 */ 1447 pungetc(); 1448 USTPUTC(')', out); 1449 } 1450 } 1451 break; 1452 case CBQUOTE: /* '`' */ 1453 out = parsebackq(out, &bqlist, 1, 1454 state[level].syntax == DQSYNTAX && 1455 (eofmark == NULL || newvarnest > 0), 1456 state[level].syntax == DQSYNTAX || state[level].syntax == ARISYNTAX); 1457 break; 1458 case CEOF: 1459 goto endword; /* exit outer loop */ 1460 case CIGN: 1461 break; 1462 default: 1463 if (level == 0) 1464 goto endword; /* exit outer loop */ 1465 USTPUTC(c, out); 1466 } 1467 c = pgetc_macro(); 1468 } 1469 } 1470 endword: 1471 if (state[level].syntax == ARISYNTAX) 1472 synerror("Missing '))'"); 1473 if (state[level].syntax != BASESYNTAX && eofmark == NULL) 1474 synerror("Unterminated quoted string"); 1475 if (state[level].category == TSTATE_VAR_OLD || 1476 state[level].category == TSTATE_VAR_NEW) { 1477 startlinno = plinno; 1478 synerror("Missing '}'"); 1479 } 1480 if (state != state_static) 1481 parser_temp_free_upto(state); 1482 USTPUTC('\0', out); 1483 len = out - stackblock(); 1484 out = stackblock(); 1485 if (eofmark == NULL) { 1486 if ((c == '>' || c == '<') 1487 && quotef == 0 1488 && len <= 2 1489 && (*out == '\0' || is_digit(*out))) { 1490 PARSEREDIR(); 1491 return lasttoken = TREDIR; 1492 } else { 1493 pungetc(); 1494 } 1495 } 1496 quoteflag = quotef; 1497 backquotelist = bqlist; 1498 grabstackblock(len); 1499 wordtext = out; 1500 return lasttoken = TWORD; 1501 /* end of readtoken routine */ 1502 1503 1504 /* 1505 * Check to see whether we are at the end of the here document. When this 1506 * is called, c is set to the first character of the next input line. If 1507 * we are at the end of the here document, this routine sets the c to PEOF. 1508 */ 1509 1510 checkend: { 1511 if (eofmark) { 1512 if (striptabs) { 1513 while (c == '\t') 1514 c = pgetc(); 1515 } 1516 if (c == *eofmark) { 1517 if (pfgets(line, sizeof line) != NULL) { 1518 char *p, *q; 1519 1520 p = line; 1521 for (q = eofmark + 1 ; *q && *p == *q ; p++, q++); 1522 if ((*p == '\0' || *p == '\n') && *q == '\0') { 1523 c = PEOF; 1524 if (*p == '\n') { 1525 plinno++; 1526 needprompt = doprompt; 1527 } 1528 } else { 1529 pushstring(line, strlen(line), NULL); 1530 } 1531 } 1532 } 1533 } 1534 goto checkend_return; 1535 } 1536 1537 1538 /* 1539 * Parse a redirection operator. The variable "out" points to a string 1540 * specifying the fd to be redirected. The variable "c" contains the 1541 * first character of the redirection operator. 1542 */ 1543 1544 parseredir: { 1545 char fd = *out; 1546 union node *np; 1547 1548 np = (union node *)stalloc(sizeof (struct nfile)); 1549 if (c == '>') { 1550 np->nfile.fd = 1; 1551 c = pgetc(); 1552 if (c == '>') 1553 np->type = NAPPEND; 1554 else if (c == '&') 1555 np->type = NTOFD; 1556 else if (c == '|') 1557 np->type = NCLOBBER; 1558 else { 1559 np->type = NTO; 1560 pungetc(); 1561 } 1562 } else { /* c == '<' */ 1563 np->nfile.fd = 0; 1564 c = pgetc(); 1565 if (c == '<') { 1566 if (sizeof (struct nfile) != sizeof (struct nhere)) { 1567 np = (union node *)stalloc(sizeof (struct nhere)); 1568 np->nfile.fd = 0; 1569 } 1570 np->type = NHERE; 1571 heredoc = (struct heredoc *)stalloc(sizeof (struct heredoc)); 1572 heredoc->here = np; 1573 if ((c = pgetc()) == '-') { 1574 heredoc->striptabs = 1; 1575 } else { 1576 heredoc->striptabs = 0; 1577 pungetc(); 1578 } 1579 } else if (c == '&') 1580 np->type = NFROMFD; 1581 else if (c == '>') 1582 np->type = NFROMTO; 1583 else { 1584 np->type = NFROM; 1585 pungetc(); 1586 } 1587 } 1588 if (fd != '\0') 1589 np->nfile.fd = digit_val(fd); 1590 redirnode = np; 1591 goto parseredir_return; 1592 } 1593 1594 1595 /* 1596 * Parse a substitution. At this point, we have read the dollar sign 1597 * and nothing else. 1598 */ 1599 1600 parsesub: { 1601 char buf[10]; 1602 int subtype; 1603 int typeloc; 1604 int flags; 1605 char *p; 1606 static const char types[] = "}-+?="; 1607 int bracketed_name = 0; /* used to handle ${[0-9]*} variables */ 1608 int linno; 1609 int length; 1610 int c1; 1611 1612 c = pgetc(); 1613 if (c == '(') { /* $(command) or $((arith)) */ 1614 if (pgetc() == '(') { 1615 PARSEARITH(); 1616 } else { 1617 pungetc(); 1618 out = parsebackq(out, &bqlist, 0, 1619 state[level].syntax == DQSYNTAX && 1620 (eofmark == NULL || newvarnest > 0), 1621 state[level].syntax == DQSYNTAX || 1622 state[level].syntax == ARISYNTAX); 1623 } 1624 } else if (c == '{' || is_name(c) || is_special(c)) { 1625 USTPUTC(CTLVAR, out); 1626 typeloc = out - stackblock(); 1627 USTPUTC(VSNORMAL, out); 1628 subtype = VSNORMAL; 1629 flags = 0; 1630 if (c == '{') { 1631 bracketed_name = 1; 1632 c = pgetc(); 1633 subtype = 0; 1634 } 1635 varname: 1636 if (!is_eof(c) && is_name(c)) { 1637 length = 0; 1638 do { 1639 STPUTC(c, out); 1640 c = pgetc(); 1641 length++; 1642 } while (!is_eof(c) && is_in_name(c)); 1643 if (length == 6 && 1644 strncmp(out - length, "LINENO", length) == 0) { 1645 /* Replace the variable name with the 1646 * current line number. */ 1647 linno = plinno; 1648 if (funclinno != 0) 1649 linno -= funclinno - 1; 1650 snprintf(buf, sizeof(buf), "%d", linno); 1651 STADJUST(-6, out); 1652 STPUTS(buf, out); 1653 flags |= VSLINENO; 1654 } 1655 } else if (is_digit(c)) { 1656 if (bracketed_name) { 1657 do { 1658 STPUTC(c, out); 1659 c = pgetc(); 1660 } while (is_digit(c)); 1661 } else { 1662 STPUTC(c, out); 1663 c = pgetc(); 1664 } 1665 } else if (is_special(c)) { 1666 c1 = c; 1667 c = pgetc(); 1668 if (subtype == 0 && c1 == '#') { 1669 subtype = VSLENGTH; 1670 if (strchr(types, c) == NULL && c != ':' && 1671 c != '#' && c != '%') 1672 goto varname; 1673 c1 = c; 1674 c = pgetc(); 1675 if (c1 != '}' && c == '}') { 1676 pungetc(); 1677 c = c1; 1678 goto varname; 1679 } 1680 pungetc(); 1681 c = c1; 1682 c1 = '#'; 1683 subtype = 0; 1684 } 1685 USTPUTC(c1, out); 1686 } else { 1687 subtype = VSERROR; 1688 if (c == '}') 1689 pungetc(); 1690 else if (c == '\n' || c == PEOF) 1691 synerror("Unexpected end of line in substitution"); 1692 else 1693 USTPUTC(c, out); 1694 } 1695 if (subtype == 0) { 1696 switch (c) { 1697 case ':': 1698 flags |= VSNUL; 1699 c = pgetc(); 1700 /*FALLTHROUGH*/ 1701 default: 1702 p = strchr(types, c); 1703 if (p == NULL) { 1704 if (c == '\n' || c == PEOF) 1705 synerror("Unexpected end of line in substitution"); 1706 if (flags == VSNUL) 1707 STPUTC(':', out); 1708 STPUTC(c, out); 1709 subtype = VSERROR; 1710 } else 1711 subtype = p - types + VSNORMAL; 1712 break; 1713 case '%': 1714 case '#': 1715 { 1716 int cc = c; 1717 subtype = c == '#' ? VSTRIMLEFT : 1718 VSTRIMRIGHT; 1719 c = pgetc(); 1720 if (c == cc) 1721 subtype++; 1722 else 1723 pungetc(); 1724 break; 1725 } 1726 } 1727 } else if (subtype != VSERROR) { 1728 if (subtype == VSLENGTH && c != '}') 1729 subtype = VSERROR; 1730 pungetc(); 1731 } 1732 STPUTC('=', out); 1733 if (state[level].syntax == DQSYNTAX || 1734 state[level].syntax == ARISYNTAX) 1735 flags |= VSQUOTE; 1736 *(stackblock() + typeloc) = subtype | flags; 1737 if (subtype != VSNORMAL) { 1738 if (level + 1 >= maxnest) { 1739 maxnest *= 2; 1740 if (state == state_static) { 1741 state = parser_temp_alloc( 1742 maxnest * sizeof(*state)); 1743 memcpy(state, state_static, 1744 MAXNEST_static * sizeof(*state)); 1745 } else 1746 state = parser_temp_realloc(state, 1747 maxnest * sizeof(*state)); 1748 } 1749 level++; 1750 state[level].parenlevel = 0; 1751 if (subtype == VSMINUS || subtype == VSPLUS || 1752 subtype == VSQUESTION || subtype == VSASSIGN) { 1753 /* 1754 * For operators that were in the Bourne shell, 1755 * inherit the double-quote state. 1756 */ 1757 state[level].syntax = state[level - 1].syntax; 1758 state[level].category = TSTATE_VAR_OLD; 1759 } else { 1760 /* 1761 * The other operators take a pattern, 1762 * so go to BASESYNTAX. 1763 * Also, ' and " are now special, even 1764 * in here documents. 1765 */ 1766 state[level].syntax = BASESYNTAX; 1767 state[level].category = TSTATE_VAR_NEW; 1768 newvarnest++; 1769 } 1770 } 1771 } else if (c == '\'' && state[level].syntax == BASESYNTAX) { 1772 /* $'cstylequotes' */ 1773 USTPUTC(CTLQUOTEMARK, out); 1774 state[level].syntax = SQSYNTAX; 1775 sqiscstyle = 1; 1776 } else { 1777 USTPUTC('$', out); 1778 pungetc(); 1779 } 1780 goto parsesub_return; 1781 } 1782 1783 1784 /* 1785 * Parse an arithmetic expansion (indicate start of one and set state) 1786 */ 1787 parsearith: { 1788 1789 if (level + 1 >= maxnest) { 1790 maxnest *= 2; 1791 if (state == state_static) { 1792 state = parser_temp_alloc( 1793 maxnest * sizeof(*state)); 1794 memcpy(state, state_static, 1795 MAXNEST_static * sizeof(*state)); 1796 } else 1797 state = parser_temp_realloc(state, 1798 maxnest * sizeof(*state)); 1799 } 1800 level++; 1801 state[level].syntax = ARISYNTAX; 1802 state[level].parenlevel = 0; 1803 state[level].category = TSTATE_ARITH; 1804 USTPUTC(CTLARI, out); 1805 if (state[level - 1].syntax == DQSYNTAX) 1806 USTPUTC('"',out); 1807 else 1808 USTPUTC(' ',out); 1809 goto parsearith_return; 1810 } 1811 1812 } /* end of readtoken */ 1813 1814 1815 1816 #ifdef mkinit 1817 RESET { 1818 tokpushback = 0; 1819 checkkwd = 0; 1820 } 1821 #endif 1822 1823 /* 1824 * Returns true if the text contains nothing to expand (no dollar signs 1825 * or backquotes). 1826 */ 1827 1828 static int 1829 noexpand(char *text) 1830 { 1831 char *p; 1832 char c; 1833 1834 p = text; 1835 while ((c = *p++) != '\0') { 1836 if ( c == CTLQUOTEMARK) 1837 continue; 1838 if (c == CTLESC) 1839 p++; 1840 else if (BASESYNTAX[(int)c] == CCTL) 1841 return 0; 1842 } 1843 return 1; 1844 } 1845 1846 1847 /* 1848 * Return true if the argument is a legal variable name (a letter or 1849 * underscore followed by zero or more letters, underscores, and digits). 1850 */ 1851 1852 int 1853 goodname(const char *name) 1854 { 1855 const char *p; 1856 1857 p = name; 1858 if (! is_name(*p)) 1859 return 0; 1860 while (*++p) { 1861 if (! is_in_name(*p)) 1862 return 0; 1863 } 1864 return 1; 1865 } 1866 1867 1868 int 1869 isassignment(const char *p) 1870 { 1871 if (!is_name(*p)) 1872 return 0; 1873 p++; 1874 for (;;) { 1875 if (*p == '=') 1876 return 1; 1877 else if (!is_in_name(*p)) 1878 return 0; 1879 p++; 1880 } 1881 } 1882 1883 1884 /* 1885 * Called when an unexpected token is read during the parse. The argument 1886 * is the token that is expected, or -1 if more than one type of token can 1887 * occur at this point. 1888 */ 1889 1890 static void 1891 synexpect(int token) 1892 { 1893 char msg[64]; 1894 1895 if (token >= 0) { 1896 fmtstr(msg, 64, "%s unexpected (expecting %s)", 1897 tokname[lasttoken], tokname[token]); 1898 } else { 1899 fmtstr(msg, 64, "%s unexpected", tokname[lasttoken]); 1900 } 1901 synerror(msg); 1902 } 1903 1904 1905 static void 1906 synerror(const char *msg) 1907 { 1908 if (commandname) 1909 outfmt(out2, "%s: %d: ", commandname, startlinno); 1910 outfmt(out2, "Syntax error: %s\n", msg); 1911 error((char *)NULL); 1912 } 1913 1914 static void 1915 setprompt(int which) 1916 { 1917 whichprompt = which; 1918 1919 #ifndef NO_HISTORY 1920 if (!el) 1921 #endif 1922 { 1923 out2str(getprompt(NULL)); 1924 flushout(out2); 1925 } 1926 } 1927 1928 /* 1929 * called by editline -- any expansions to the prompt 1930 * should be added here. 1931 */ 1932 char * 1933 getprompt(void *unused __unused) 1934 { 1935 static char ps[PROMPTLEN]; 1936 char *fmt; 1937 const char *pwd; 1938 int i, trim; 1939 static char internal_error[] = "??"; 1940 1941 /* 1942 * Select prompt format. 1943 */ 1944 switch (whichprompt) { 1945 case 0: 1946 fmt = nullstr; 1947 break; 1948 case 1: 1949 fmt = ps1val(); 1950 break; 1951 case 2: 1952 fmt = ps2val(); 1953 break; 1954 default: 1955 return internal_error; 1956 } 1957 1958 /* 1959 * Format prompt string. 1960 */ 1961 for (i = 0; (i < 127) && (*fmt != '\0'); i++, fmt++) 1962 if (*fmt == '\\') 1963 switch (*++fmt) { 1964 1965 /* 1966 * Hostname. 1967 * 1968 * \h specifies just the local hostname, 1969 * \H specifies fully-qualified hostname. 1970 */ 1971 case 'h': 1972 case 'H': 1973 ps[i] = '\0'; 1974 gethostname(&ps[i], PROMPTLEN - i); 1975 /* Skip to end of hostname. */ 1976 trim = (*fmt == 'h') ? '.' : '\0'; 1977 while ((ps[i+1] != '\0') && (ps[i+1] != trim)) 1978 i++; 1979 break; 1980 1981 /* 1982 * Working directory. 1983 * 1984 * \W specifies just the final component, 1985 * \w specifies the entire path. 1986 */ 1987 case 'W': 1988 case 'w': 1989 pwd = lookupvar("PWD"); 1990 if (pwd == NULL) 1991 pwd = "?"; 1992 if (*fmt == 'W' && 1993 *pwd == '/' && pwd[1] != '\0') 1994 strlcpy(&ps[i], strrchr(pwd, '/') + 1, 1995 PROMPTLEN - i); 1996 else 1997 strlcpy(&ps[i], pwd, PROMPTLEN - i); 1998 /* Skip to end of path. */ 1999 while (ps[i + 1] != '\0') 2000 i++; 2001 break; 2002 2003 /* 2004 * Superuser status. 2005 * 2006 * '$' for normal users, '#' for root. 2007 */ 2008 case '$': 2009 ps[i] = (geteuid() != 0) ? '$' : '#'; 2010 break; 2011 2012 /* 2013 * A literal \. 2014 */ 2015 case '\\': 2016 ps[i] = '\\'; 2017 break; 2018 2019 /* 2020 * Emit unrecognized formats verbatim. 2021 */ 2022 default: 2023 ps[i++] = '\\'; 2024 ps[i] = *fmt; 2025 break; 2026 } 2027 else 2028 ps[i] = *fmt; 2029 ps[i] = '\0'; 2030 return (ps); 2031 } 2032