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 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)parser.c 8.7 (Berkeley) 5/16/95 37 * $FreeBSD: src/bin/sh/parser.c,v 1.58 2006/11/05 18:36:05 stefanf Exp $ 38 * $DragonFly: src/bin/sh/parser.c,v 1.12 2007/01/18 17:03:18 corecode Exp $ 39 */ 40 41 #include <stdlib.h> 42 #include <unistd.h> 43 44 #include "shell.h" 45 #include "parser.h" 46 #include "nodes.h" 47 #include "expand.h" /* defines rmescapes() */ 48 #include "syntax.h" 49 #include "options.h" 50 #include "input.h" 51 #include "output.h" 52 #include "var.h" 53 #include "error.h" 54 #include "memalloc.h" 55 #include "mystring.h" 56 #include "alias.h" 57 #include "show.h" 58 #include "eval.h" 59 #ifndef NO_HISTORY 60 #include "myhistedit.h" 61 #endif 62 63 /* 64 * Shell command parser. 65 */ 66 67 #define EOFMARKLEN 79 68 #define PROMPTLEN 128 69 70 /* values returned by readtoken */ 71 #include "token.h" 72 73 74 75 struct heredoc { 76 struct heredoc *next; /* next here document in list */ 77 union node *here; /* redirection node */ 78 char *eofmark; /* string indicating end of input */ 79 int striptabs; /* if set, strip leading tabs */ 80 }; 81 82 83 84 STATIC struct heredoc *heredoclist; /* list of here documents to read */ 85 STATIC int parsebackquote; /* nonzero if we are inside backquotes */ 86 STATIC int doprompt; /* if set, prompt the user */ 87 STATIC int needprompt; /* true if interactive and at start of line */ 88 STATIC int lasttoken; /* last token read */ 89 MKINIT int tokpushback; /* last token pushed back */ 90 STATIC char *wordtext; /* text of last word returned by readtoken */ 91 /* 92 * 1 == check for kwds 93 * 2 == also eat newlines 94 * 3 == check for TNOT 95 */ 96 MKINIT int checkkwd; 97 STATIC struct nodelist *backquotelist; 98 STATIC union node *redirnode; 99 STATIC struct heredoc *heredoc; 100 STATIC int quoteflag; /* set if (part of) last token was quoted */ 101 STATIC int startlinno; /* line # where last token started */ 102 STATIC int funclinno; /* line # where the current function started */ 103 104 /* XXX When 'noaliases' is set to one, no alias expansion takes place. */ 105 static int noaliases = 0; 106 107 108 STATIC union node *list(int); 109 STATIC union node *andor(void); 110 STATIC union node *pipeline(void); 111 STATIC union node *command(void); 112 STATIC union node *simplecmd(union node **, union node *); 113 STATIC union node *makename(void); 114 STATIC void parsefname(void); 115 STATIC void parseheredoc(void); 116 STATIC int peektoken(void); 117 STATIC int readtoken(void); 118 STATIC int xxreadtoken(void); 119 STATIC int readtoken1(int, char const *, char *, int); 120 STATIC int noexpand(char *); 121 STATIC void synexpect(int); 122 STATIC void synerror(const char *); 123 STATIC void setprompt(int); 124 125 126 /* 127 * Read and parse a command. Returns NEOF on end of file. (NULL is a 128 * valid parse tree indicating a blank line.) 129 */ 130 131 union node * 132 parsecmd(int interact) 133 { 134 int t; 135 136 tokpushback = 0; 137 doprompt = interact; 138 if (doprompt) 139 setprompt(1); 140 else 141 setprompt(0); 142 needprompt = 0; 143 t = readtoken(); 144 if (t == TEOF) 145 return NEOF; 146 if (t == TNL) 147 return NULL; 148 tokpushback++; 149 return list(1); 150 } 151 152 153 STATIC union node * 154 list(int nlflag) 155 { 156 union node *n1, *n2, *n3; 157 int tok; 158 159 checkkwd = 2; 160 if (nlflag == 0 && tokendlist[peektoken()]) 161 return NULL; 162 n1 = NULL; 163 for (;;) { 164 n2 = andor(); 165 tok = readtoken(); 166 if (tok == TBACKGND) { 167 if (n2->type == NCMD || n2->type == NPIPE) { 168 n2->ncmd.backgnd = 1; 169 } else if (n2->type == NREDIR) { 170 n2->type = NBACKGND; 171 } else { 172 n3 = (union node *)stalloc(sizeof (struct nredir)); 173 n3->type = NBACKGND; 174 n3->nredir.n = n2; 175 n3->nredir.redirect = NULL; 176 n2 = n3; 177 } 178 } 179 if (n1 == NULL) { 180 n1 = n2; 181 } 182 else { 183 n3 = (union node *)stalloc(sizeof (struct nbinary)); 184 n3->type = NSEMI; 185 n3->nbinary.ch1 = n1; 186 n3->nbinary.ch2 = n2; 187 n1 = n3; 188 } 189 switch (tok) { 190 case TBACKGND: 191 case TSEMI: 192 tok = readtoken(); 193 /* FALLTHROUGH */ 194 case TNL: 195 if (tok == TNL) { 196 parseheredoc(); 197 if (nlflag) 198 return n1; 199 } else { 200 tokpushback++; 201 } 202 checkkwd = 2; 203 if (tokendlist[peektoken()]) 204 return n1; 205 break; 206 case TEOF: 207 if (heredoclist) 208 parseheredoc(); 209 else 210 pungetc(); /* push back EOF on input */ 211 return n1; 212 default: 213 if (nlflag) 214 synexpect(-1); 215 tokpushback++; 216 return n1; 217 } 218 } 219 } 220 221 222 223 STATIC union node * 224 andor(void) 225 { 226 union node *n1, *n2, *n3; 227 int t; 228 229 n1 = pipeline(); 230 for (;;) { 231 if ((t = readtoken()) == TAND) { 232 t = NAND; 233 } else if (t == TOR) { 234 t = NOR; 235 } else { 236 tokpushback++; 237 return n1; 238 } 239 n2 = pipeline(); 240 n3 = (union node *)stalloc(sizeof (struct nbinary)); 241 n3->type = t; 242 n3->nbinary.ch1 = n1; 243 n3->nbinary.ch2 = n2; 244 n1 = n3; 245 } 246 } 247 248 249 250 STATIC union node * 251 pipeline(void) 252 { 253 union node *n1, *n2, *pipenode; 254 struct nodelist *lp, *prev; 255 int negate; 256 257 negate = 0; 258 TRACE(("pipeline: entered\n")); 259 260 checkkwd = 3; 261 while (readtoken() == TNOT) 262 negate = !negate; 263 tokpushback++; 264 265 n1 = command(); 266 if (readtoken() == TPIPE) { 267 pipenode = (union node *)stalloc(sizeof (struct npipe)); 268 pipenode->type = NPIPE; 269 pipenode->npipe.backgnd = 0; 270 lp = (struct nodelist *)stalloc(sizeof (struct nodelist)); 271 pipenode->npipe.cmdlist = lp; 272 lp->n = n1; 273 do { 274 int innernegate = 0; 275 276 checkkwd = 3; 277 while (readtoken() == TNOT) 278 innernegate = !innernegate; 279 tokpushback++; 280 281 prev = lp; 282 lp = (struct nodelist *)stalloc(sizeof (struct nodelist)); 283 lp->n = command(); 284 prev->next = lp; 285 286 if (innernegate) { 287 n2 = (union node *)stalloc(sizeof (struct nnot)); 288 n2->type = NNOT; 289 n2->nnot.com = lp->n; 290 lp->n = n2; 291 } 292 } while (readtoken() == TPIPE); 293 lp->next = NULL; 294 n1 = pipenode; 295 } 296 tokpushback++; 297 if (negate) { 298 n2 = (union node *)stalloc(sizeof (struct nnot)); 299 n2->type = NNOT; 300 n2->nnot.com = n1; 301 return n2; 302 } else 303 return n1; 304 } 305 306 307 308 STATIC union node * 309 command(void) 310 { 311 union node *n1, *n2; 312 union node *ap, **app; 313 union node *cp, **cpp; 314 union node *redir, **rpp; 315 int t; 316 317 checkkwd = 2; 318 redir = NULL; 319 n1 = NULL; 320 rpp = &redir; 321 322 /* Check for redirection which may precede command */ 323 while (readtoken() == TREDIR) { 324 *rpp = n2 = redirnode; 325 rpp = &n2->nfile.next; 326 parsefname(); 327 } 328 tokpushback++; 329 330 switch (readtoken()) { 331 case TIF: 332 n1 = (union node *)stalloc(sizeof (struct nif)); 333 n1->type = NIF; 334 if ((n1->nif.test = list(0)) == NULL) 335 synexpect(-1); 336 if (readtoken() != TTHEN) 337 synexpect(TTHEN); 338 n1->nif.ifpart = list(0); 339 n2 = n1; 340 while (readtoken() == TELIF) { 341 n2->nif.elsepart = (union node *)stalloc(sizeof (struct nif)); 342 n2 = n2->nif.elsepart; 343 n2->type = NIF; 344 if ((n2->nif.test = list(0)) == NULL) 345 synexpect(-1); 346 if (readtoken() != TTHEN) 347 synexpect(TTHEN); 348 n2->nif.ifpart = list(0); 349 } 350 if (lasttoken == TELSE) 351 n2->nif.elsepart = list(0); 352 else { 353 n2->nif.elsepart = NULL; 354 tokpushback++; 355 } 356 if (readtoken() != TFI) 357 synexpect(TFI); 358 checkkwd = 1; 359 break; 360 case TWHILE: 361 case TUNTIL: { 362 int got; 363 n1 = (union node *)stalloc(sizeof (struct nbinary)); 364 n1->type = (lasttoken == TWHILE)? NWHILE : NUNTIL; 365 if ((n1->nbinary.ch1 = list(0)) == NULL) 366 synexpect(-1); 367 if ((got=readtoken()) != TDO) { 368 TRACE(("expecting DO got %s %s\n", tokname[got], got == TWORD ? wordtext : "")); 369 synexpect(TDO); 370 } 371 n1->nbinary.ch2 = list(0); 372 if (readtoken() != TDONE) 373 synexpect(TDONE); 374 checkkwd = 1; 375 break; 376 } 377 case TFOR: 378 if (readtoken() != TWORD || quoteflag || ! goodname(wordtext)) 379 synerror("Bad for loop variable"); 380 n1 = (union node *)stalloc(sizeof (struct nfor)); 381 n1->type = NFOR; 382 n1->nfor.var = wordtext; 383 if (readtoken() == TWORD && ! quoteflag && equal(wordtext, "in")) { 384 app = ≈ 385 while (readtoken() == TWORD) { 386 n2 = (union node *)stalloc(sizeof (struct narg)); 387 n2->type = NARG; 388 n2->narg.text = wordtext; 389 n2->narg.backquote = backquotelist; 390 *app = n2; 391 app = &n2->narg.next; 392 } 393 *app = NULL; 394 n1->nfor.args = ap; 395 if (lasttoken != TNL && lasttoken != TSEMI) 396 synexpect(-1); 397 } else { 398 static char argvars[5] = { 399 CTLVAR, VSNORMAL|VSQUOTE, '@', '=', '\0' 400 }; 401 n2 = (union node *)stalloc(sizeof (struct narg)); 402 n2->type = NARG; 403 n2->narg.text = argvars; 404 n2->narg.backquote = NULL; 405 n2->narg.next = NULL; 406 n1->nfor.args = n2; 407 /* 408 * Newline or semicolon here is optional (but note 409 * that the original Bourne shell only allowed NL). 410 */ 411 if (lasttoken != TNL && lasttoken != TSEMI) 412 tokpushback++; 413 } 414 checkkwd = 2; 415 if ((t = readtoken()) == TDO) 416 t = TDONE; 417 else if (t == TBEGIN) 418 t = TEND; 419 else 420 synexpect(-1); 421 n1->nfor.body = list(0); 422 if (readtoken() != t) 423 synexpect(t); 424 checkkwd = 1; 425 break; 426 case TCASE: 427 n1 = (union node *)stalloc(sizeof (struct ncase)); 428 n1->type = NCASE; 429 if (readtoken() != TWORD) 430 synexpect(TWORD); 431 n1->ncase.expr = n2 = (union node *)stalloc(sizeof (struct narg)); 432 n2->type = NARG; 433 n2->narg.text = wordtext; 434 n2->narg.backquote = backquotelist; 435 n2->narg.next = NULL; 436 while (readtoken() == TNL); 437 if (lasttoken != TWORD || ! equal(wordtext, "in")) 438 synerror("expecting \"in\""); 439 cpp = &n1->ncase.cases; 440 noaliases = 1; /* turn off alias expansion */ 441 checkkwd = 2, readtoken(); 442 while (lasttoken != TESAC) { 443 *cpp = cp = (union node *)stalloc(sizeof (struct nclist)); 444 cp->type = NCLIST; 445 app = &cp->nclist.pattern; 446 if (lasttoken == TLP) 447 readtoken(); 448 for (;;) { 449 *app = ap = (union node *)stalloc(sizeof (struct narg)); 450 ap->type = NARG; 451 ap->narg.text = wordtext; 452 ap->narg.backquote = backquotelist; 453 if (checkkwd = 2, readtoken() != TPIPE) 454 break; 455 app = &ap->narg.next; 456 readtoken(); 457 } 458 ap->narg.next = NULL; 459 if (lasttoken != TRP) 460 noaliases = 0, synexpect(TRP); 461 cp->nclist.body = list(0); 462 463 checkkwd = 2; 464 if ((t = readtoken()) != TESAC) { 465 if (t != TENDCASE) 466 noaliases = 0, synexpect(TENDCASE); 467 else 468 checkkwd = 2, readtoken(); 469 } 470 cpp = &cp->nclist.next; 471 } 472 noaliases = 0; /* reset alias expansion */ 473 *cpp = NULL; 474 checkkwd = 1; 475 break; 476 case TLP: 477 n1 = (union node *)stalloc(sizeof (struct nredir)); 478 n1->type = NSUBSHELL; 479 n1->nredir.n = list(0); 480 n1->nredir.redirect = NULL; 481 if (readtoken() != TRP) 482 synexpect(TRP); 483 checkkwd = 1; 484 break; 485 case TBEGIN: 486 n1 = list(0); 487 if (readtoken() != TEND) 488 synexpect(TEND); 489 checkkwd = 1; 490 break; 491 /* Handle an empty command like other simple commands. */ 492 case TSEMI: 493 case TAND: 494 case TOR: 495 /* 496 * An empty command before a ; doesn't make much sense, and 497 * should certainly be disallowed in the case of `if ;'. 498 */ 499 if (!redir) 500 synexpect(-1); 501 case TNL: 502 case TEOF: 503 case TWORD: 504 case TRP: 505 tokpushback++; 506 return simplecmd(rpp, redir); 507 default: 508 synexpect(-1); 509 } 510 511 /* Now check for redirection which may follow command */ 512 while (readtoken() == TREDIR) { 513 *rpp = n2 = redirnode; 514 rpp = &n2->nfile.next; 515 parsefname(); 516 } 517 tokpushback++; 518 *rpp = NULL; 519 if (redir) { 520 if (n1->type != NSUBSHELL) { 521 n2 = (union node *)stalloc(sizeof (struct nredir)); 522 n2->type = NREDIR; 523 n2->nredir.n = n1; 524 n1 = n2; 525 } 526 n1->nredir.redirect = redir; 527 } 528 return n1; 529 } 530 531 532 STATIC union node * 533 simplecmd(union node **rpp, union node *redir) 534 { 535 union node *args, **app; 536 union node **orig_rpp = rpp; 537 union node *n = NULL; 538 539 /* If we don't have any redirections already, then we must reset */ 540 /* rpp to be the address of the local redir variable. */ 541 if (redir == 0) 542 rpp = &redir; 543 544 args = NULL; 545 app = &args; 546 /* 547 * We save the incoming value, because we need this for shell 548 * functions. There can not be a redirect or an argument between 549 * the function name and the open parenthesis. 550 */ 551 orig_rpp = rpp; 552 553 for (;;) { 554 if (readtoken() == TWORD) { 555 n = (union node *)stalloc(sizeof (struct narg)); 556 n->type = NARG; 557 n->narg.text = wordtext; 558 n->narg.backquote = backquotelist; 559 *app = n; 560 app = &n->narg.next; 561 } else if (lasttoken == TREDIR) { 562 *rpp = n = redirnode; 563 rpp = &n->nfile.next; 564 parsefname(); /* read name of redirection file */ 565 } else if (lasttoken == TLP && app == &args->narg.next 566 && rpp == orig_rpp) { 567 /* We have a function */ 568 if (readtoken() != TRP) 569 synexpect(TRP); 570 funclinno = plinno; 571 #ifdef notdef 572 if (! goodname(n->narg.text)) 573 synerror("Bad function name"); 574 #endif 575 n->type = NDEFUN; 576 n->narg.next = command(); 577 funclinno = 0; 578 return n; 579 } else { 580 tokpushback++; 581 break; 582 } 583 } 584 *app = NULL; 585 *rpp = NULL; 586 n = (union node *)stalloc(sizeof (struct ncmd)); 587 n->type = NCMD; 588 n->ncmd.backgnd = 0; 589 n->ncmd.args = args; 590 n->ncmd.redirect = redir; 591 return n; 592 } 593 594 STATIC union node * 595 makename(void) 596 { 597 union node *n; 598 599 n = (union node *)stalloc(sizeof (struct narg)); 600 n->type = NARG; 601 n->narg.next = NULL; 602 n->narg.text = wordtext; 603 n->narg.backquote = backquotelist; 604 return n; 605 } 606 607 void 608 fixredir(union node *n, const char *text, int err) 609 { 610 TRACE(("Fix redir %s %d\n", text, err)); 611 if (!err) 612 n->ndup.vname = NULL; 613 614 if (is_digit(text[0]) && text[1] == '\0') 615 n->ndup.dupfd = digit_val(text[0]); 616 else if (text[0] == '-' && text[1] == '\0') 617 n->ndup.dupfd = -1; 618 else { 619 620 if (err) 621 synerror("Bad fd number"); 622 else 623 n->ndup.vname = makename(); 624 } 625 } 626 627 628 STATIC void 629 parsefname(void) 630 { 631 union node *n = redirnode; 632 633 if (readtoken() != TWORD) 634 synexpect(-1); 635 if (n->type == NHERE) { 636 struct heredoc *here = heredoc; 637 struct heredoc *p; 638 int i; 639 640 if (quoteflag == 0) 641 n->type = NXHERE; 642 TRACE(("Here document %d\n", n->type)); 643 if (here->striptabs) { 644 while (*wordtext == '\t') 645 wordtext++; 646 } 647 if (! noexpand(wordtext) || (i = strlen(wordtext)) == 0 || i > EOFMARKLEN) 648 synerror("Illegal eof marker for << redirection"); 649 rmescapes(wordtext); 650 here->eofmark = wordtext; 651 here->next = NULL; 652 if (heredoclist == NULL) 653 heredoclist = here; 654 else { 655 for (p = heredoclist ; p->next ; p = p->next); 656 p->next = here; 657 } 658 } else if (n->type == NTOFD || n->type == NFROMFD) { 659 fixredir(n, wordtext, 0); 660 } else { 661 n->nfile.fname = makename(); 662 } 663 } 664 665 666 /* 667 * Input any here documents. 668 */ 669 670 STATIC void 671 parseheredoc(void) 672 { 673 struct heredoc *here; 674 union node *n; 675 676 while (heredoclist) { 677 here = heredoclist; 678 heredoclist = here->next; 679 if (needprompt) { 680 setprompt(2); 681 needprompt = 0; 682 } 683 readtoken1(pgetc(), here->here->type == NHERE? SQSYNTAX : DQSYNTAX, 684 here->eofmark, here->striptabs); 685 n = (union node *)stalloc(sizeof (struct narg)); 686 n->narg.type = NARG; 687 n->narg.next = NULL; 688 n->narg.text = wordtext; 689 n->narg.backquote = backquotelist; 690 here->here->nhere.doc = n; 691 } 692 } 693 694 STATIC int 695 peektoken(void) 696 { 697 int t; 698 699 t = readtoken(); 700 tokpushback++; 701 return (t); 702 } 703 704 STATIC int 705 readtoken(void) 706 { 707 int t; 708 int savecheckkwd = checkkwd; 709 struct alias *ap; 710 #ifdef DEBUG 711 int alreadyseen = tokpushback; 712 #endif 713 714 top: 715 t = xxreadtoken(); 716 717 if (checkkwd) { 718 /* 719 * eat newlines 720 */ 721 if (checkkwd > 1) { 722 checkkwd = 0; 723 while (t == TNL) { 724 parseheredoc(); 725 t = xxreadtoken(); 726 } 727 } else 728 checkkwd = 0; 729 /* 730 * check for keywords and aliases 731 */ 732 if (t == TWORD && !quoteflag) 733 { 734 const char * const *pp; 735 736 for (pp = parsekwd; *pp; pp++) { 737 if (**pp == *wordtext && equal(*pp, wordtext)) 738 { 739 lasttoken = t = pp - parsekwd + KWDOFFSET; 740 TRACE(("keyword %s recognized\n", tokname[t])); 741 goto out; 742 } 743 } 744 if (noaliases == 0 && 745 (ap = lookupalias(wordtext, 1)) != NULL) { 746 pushstring(ap->val, strlen(ap->val), ap); 747 checkkwd = savecheckkwd; 748 goto top; 749 } 750 } 751 out: 752 checkkwd = 0; 753 } 754 #ifdef DEBUG 755 if (!alreadyseen) 756 TRACE(("token %s %s\n", tokname[t], t == TWORD ? wordtext : "")); 757 else 758 TRACE(("reread token %s %s\n", tokname[t], t == TWORD ? wordtext : "")); 759 #endif 760 return (t); 761 } 762 763 764 /* 765 * Read the next input token. 766 * If the token is a word, we set backquotelist to the list of cmds in 767 * backquotes. We set quoteflag to true if any part of the word was 768 * quoted. 769 * If the token is TREDIR, then we set redirnode to a structure containing 770 * the redirection. 771 * In all cases, the variable startlinno is set to the number of the line 772 * on which the token starts. 773 * 774 * [Change comment: here documents and internal procedures] 775 * [Readtoken shouldn't have any arguments. Perhaps we should make the 776 * word parsing code into a separate routine. In this case, readtoken 777 * doesn't need to have any internal procedures, but parseword does. 778 * We could also make parseoperator in essence the main routine, and 779 * have parseword (readtoken1?) handle both words and redirection.] 780 */ 781 782 #define RETURN(token) return lasttoken = token 783 784 STATIC int 785 xxreadtoken(void) 786 { 787 int c; 788 789 if (tokpushback) { 790 tokpushback = 0; 791 return lasttoken; 792 } 793 if (needprompt) { 794 setprompt(2); 795 needprompt = 0; 796 } 797 startlinno = plinno; 798 for (;;) { /* until token or start of word found */ 799 c = pgetc_macro(); 800 if (c == ' ' || c == '\t') 801 continue; /* quick check for white space first */ 802 switch (c) { 803 case ' ': case '\t': 804 continue; 805 case '#': 806 while ((c = pgetc()) != '\n' && c != PEOF); 807 pungetc(); 808 continue; 809 case '\\': 810 if (pgetc() == '\n') { 811 startlinno = ++plinno; 812 if (doprompt) 813 setprompt(2); 814 else 815 setprompt(0); 816 continue; 817 } 818 pungetc(); 819 goto breakloop; 820 case '\n': 821 plinno++; 822 needprompt = doprompt; 823 RETURN(TNL); 824 case PEOF: 825 RETURN(TEOF); 826 case '&': 827 if (pgetc() == '&') 828 RETURN(TAND); 829 pungetc(); 830 RETURN(TBACKGND); 831 case '|': 832 if (pgetc() == '|') 833 RETURN(TOR); 834 pungetc(); 835 RETURN(TPIPE); 836 case ';': 837 if (pgetc() == ';') 838 RETURN(TENDCASE); 839 pungetc(); 840 RETURN(TSEMI); 841 case '(': 842 RETURN(TLP); 843 case ')': 844 RETURN(TRP); 845 case '!': 846 if (checkkwd == 3) 847 RETURN(TNOT); 848 /* else FALLTHROUGH */ 849 default: 850 goto breakloop; 851 } 852 } 853 breakloop: 854 return readtoken1(c, BASESYNTAX, NULL, 0); 855 #undef RETURN 856 } 857 858 859 860 /* 861 * If eofmark is NULL, read a word or a redirection symbol. If eofmark 862 * is not NULL, read a here document. In the latter case, eofmark is the 863 * word which marks the end of the document and striptabs is true if 864 * leading tabs should be stripped from the document. The argument firstc 865 * is the first character of the input token or document. 866 * 867 * Because C does not have internal subroutines, I have simulated them 868 * using goto's to implement the subroutine linkage. The following macros 869 * will run code that appears at the end of readtoken1. 870 */ 871 872 #define CHECKEND() {goto checkend; checkend_return:;} 873 #define PARSEREDIR() {goto parseredir; parseredir_return:;} 874 #define PARSESUB() {goto parsesub; parsesub_return:;} 875 #define PARSEBACKQOLD() {oldstyle = 1; goto parsebackq; parsebackq_oldreturn:;} 876 #define PARSEBACKQNEW() {oldstyle = 0; goto parsebackq; parsebackq_newreturn:;} 877 #define PARSEARITH() {goto parsearith; parsearith_return:;} 878 879 STATIC int 880 readtoken1(int firstc, char const *syn, char *eofmark, int striptabs) 881 { 882 int c = firstc; 883 char const * volatile syntax = syn; 884 char * volatile out; 885 int len; 886 char line[EOFMARKLEN + 1]; 887 struct nodelist *bqlist; 888 volatile int quotef; 889 volatile int dblquote; 890 volatile int varnest; /* levels of variables expansion */ 891 volatile int arinest; /* levels of arithmetic expansion */ 892 volatile int parenlevel; /* levels of parens in arithmetic */ 893 volatile int oldstyle; 894 char const * volatile prevsyntax = NULL; /* syntax before arithmetic */ 895 int synentry; 896 897 startlinno = plinno; 898 dblquote = 0; 899 if (syntax == DQSYNTAX) 900 dblquote = 1; 901 quotef = 0; 902 bqlist = NULL; 903 varnest = 0; 904 arinest = 0; 905 parenlevel = 0; 906 907 STARTSTACKSTR(out); 908 loop: { /* for each line, until end of word */ 909 CHECKEND(); /* set c to PEOF if at end of here document */ 910 for (;;) { /* until end of line or end of word */ 911 CHECKSTRSPACE(3, out); /* permit 3 calls to USTPUTC */ 912 913 synentry = syntax[c]; 914 915 switch(synentry) { 916 case CNL: /* '\n' */ 917 if (syntax == BASESYNTAX) 918 goto endword; /* exit outer loop */ 919 USTPUTC(c, out); 920 plinno++; 921 if (doprompt) 922 setprompt(2); 923 else 924 setprompt(0); 925 c = pgetc(); 926 goto loop; /* continue outer loop */ 927 case CWORD: 928 USTPUTC(c, out); 929 break; 930 case CCTL: 931 if (eofmark == NULL || dblquote) 932 USTPUTC(CTLESC, out); 933 USTPUTC(c, out); 934 break; 935 case CBACK: /* backslash */ 936 c = pgetc(); 937 if (c == PEOF) { 938 USTPUTC('\\', out); 939 pungetc(); 940 } else if (c == '\n') { 941 plinno++; 942 if (doprompt) 943 setprompt(2); 944 else 945 setprompt(0); 946 } else { 947 if (dblquote && c != '\\' && 948 c != '`' && c != '$' && 949 (c != '"' || eofmark != NULL)) 950 USTPUTC('\\', out); 951 if (SQSYNTAX[c] == CCTL) 952 USTPUTC(CTLESC, out); 953 else if (eofmark == NULL) 954 USTPUTC(CTLQUOTEMARK, out); 955 USTPUTC(c, out); 956 quotef++; 957 } 958 break; 959 case CSQUOTE: 960 if (eofmark == NULL) 961 USTPUTC(CTLQUOTEMARK, out); 962 syntax = SQSYNTAX; 963 break; 964 case CDQUOTE: 965 if (eofmark == NULL) 966 USTPUTC(CTLQUOTEMARK, out); 967 syntax = DQSYNTAX; 968 dblquote = 1; 969 break; 970 case CENDQUOTE: 971 if (eofmark != NULL && arinest == 0 && 972 varnest == 0) { 973 USTPUTC(c, out); 974 } else { 975 if (arinest) { 976 syntax = ARISYNTAX; 977 dblquote = 0; 978 } else if (eofmark == NULL) { 979 syntax = BASESYNTAX; 980 dblquote = 0; 981 } 982 quotef++; 983 } 984 break; 985 case CVAR: /* '$' */ 986 PARSESUB(); /* parse substitution */ 987 break; 988 case CENDVAR: /* '}' */ 989 if (varnest > 0) { 990 varnest--; 991 USTPUTC(CTLENDVAR, out); 992 } else { 993 USTPUTC(c, out); 994 } 995 break; 996 case CLP: /* '(' in arithmetic */ 997 parenlevel++; 998 USTPUTC(c, out); 999 break; 1000 case CRP: /* ')' in arithmetic */ 1001 if (parenlevel > 0) { 1002 USTPUTC(c, out); 1003 --parenlevel; 1004 } else { 1005 if (pgetc() == ')') { 1006 if (--arinest == 0) { 1007 USTPUTC(CTLENDARI, out); 1008 syntax = prevsyntax; 1009 if (syntax == DQSYNTAX) 1010 dblquote = 1; 1011 else 1012 dblquote = 0; 1013 } else 1014 USTPUTC(')', out); 1015 } else { 1016 /* 1017 * unbalanced parens 1018 * (don't 2nd guess - no error) 1019 */ 1020 pungetc(); 1021 USTPUTC(')', out); 1022 } 1023 } 1024 break; 1025 case CBQUOTE: /* '`' */ 1026 PARSEBACKQOLD(); 1027 break; 1028 case CEOF: 1029 goto endword; /* exit outer loop */ 1030 default: 1031 if (varnest == 0) 1032 goto endword; /* exit outer loop */ 1033 USTPUTC(c, out); 1034 } 1035 c = pgetc_macro(); 1036 } 1037 } 1038 endword: 1039 if (syntax == ARISYNTAX) 1040 synerror("Missing '))'"); 1041 if (syntax != BASESYNTAX && ! parsebackquote && eofmark == NULL) 1042 synerror("Unterminated quoted string"); 1043 if (varnest != 0) { 1044 startlinno = plinno; 1045 synerror("Missing '}'"); 1046 } 1047 USTPUTC('\0', out); 1048 len = out - stackblock(); 1049 out = stackblock(); 1050 if (eofmark == NULL) { 1051 if ((c == '>' || c == '<') 1052 && quotef == 0 1053 && len <= 2 1054 && (*out == '\0' || is_digit(*out))) { 1055 PARSEREDIR(); 1056 return lasttoken = TREDIR; 1057 } else { 1058 pungetc(); 1059 } 1060 } 1061 quoteflag = quotef; 1062 backquotelist = bqlist; 1063 grabstackblock(len); 1064 wordtext = out; 1065 return lasttoken = TWORD; 1066 /* end of readtoken routine */ 1067 1068 1069 1070 /* 1071 * Check to see whether we are at the end of the here document. When this 1072 * is called, c is set to the first character of the next input line. If 1073 * we are at the end of the here document, this routine sets the c to PEOF. 1074 */ 1075 1076 checkend: { 1077 if (eofmark) { 1078 if (striptabs) { 1079 while (c == '\t') 1080 c = pgetc(); 1081 } 1082 if (c == *eofmark) { 1083 if (pfgets(line, sizeof line) != NULL) { 1084 char *p, *q; 1085 1086 p = line; 1087 for (q = eofmark + 1 ; *q && *p == *q ; p++, q++); 1088 if (*p == '\n' && *q == '\0') { 1089 c = PEOF; 1090 plinno++; 1091 needprompt = doprompt; 1092 } else { 1093 pushstring(line, strlen(line), NULL); 1094 } 1095 } 1096 } 1097 } 1098 goto checkend_return; 1099 } 1100 1101 1102 /* 1103 * Parse a redirection operator. The variable "out" points to a string 1104 * specifying the fd to be redirected. The variable "c" contains the 1105 * first character of the redirection operator. 1106 */ 1107 1108 parseredir: { 1109 char fd = *out; 1110 union node *np; 1111 1112 np = (union node *)stalloc(sizeof (struct nfile)); 1113 if (c == '>') { 1114 np->nfile.fd = 1; 1115 c = pgetc(); 1116 if (c == '>') 1117 np->type = NAPPEND; 1118 else if (c == '&') 1119 np->type = NTOFD; 1120 else if (c == '|') 1121 np->type = NCLOBBER; 1122 else { 1123 np->type = NTO; 1124 pungetc(); 1125 } 1126 } else { /* c == '<' */ 1127 np->nfile.fd = 0; 1128 c = pgetc(); 1129 if (c == '<') { 1130 if (sizeof (struct nfile) != sizeof (struct nhere)) { 1131 np = (union node *)stalloc(sizeof (struct nhere)); 1132 np->nfile.fd = 0; 1133 } 1134 np->type = NHERE; 1135 heredoc = (struct heredoc *)stalloc(sizeof (struct heredoc)); 1136 heredoc->here = np; 1137 if ((c = pgetc()) == '-') { 1138 heredoc->striptabs = 1; 1139 } else { 1140 heredoc->striptabs = 0; 1141 pungetc(); 1142 } 1143 } else if (c == '&') 1144 np->type = NFROMFD; 1145 else if (c == '>') 1146 np->type = NFROMTO; 1147 else { 1148 np->type = NFROM; 1149 pungetc(); 1150 } 1151 } 1152 if (fd != '\0') 1153 np->nfile.fd = digit_val(fd); 1154 redirnode = np; 1155 goto parseredir_return; 1156 } 1157 1158 1159 /* 1160 * Parse a substitution. At this point, we have read the dollar sign 1161 * and nothing else. 1162 */ 1163 1164 parsesub: { 1165 char buf[10]; 1166 int subtype; 1167 int typeloc; 1168 int flags; 1169 char *p; 1170 static const char types[] = "}-+?="; 1171 int bracketed_name = 0; /* used to handle ${[0-9]*} variables */ 1172 int i; 1173 int linno; 1174 int length; 1175 1176 c = pgetc(); 1177 if (c != '(' && c != '{' && (is_eof(c) || !is_name(c)) && 1178 !is_special(c)) { 1179 USTPUTC('$', out); 1180 pungetc(); 1181 } else if (c == '(') { /* $(command) or $((arith)) */ 1182 if (pgetc() == '(') { 1183 PARSEARITH(); 1184 } else { 1185 pungetc(); 1186 PARSEBACKQNEW(); 1187 } 1188 } else { 1189 USTPUTC(CTLVAR, out); 1190 typeloc = out - stackblock(); 1191 USTPUTC(VSNORMAL, out); 1192 subtype = VSNORMAL; 1193 flags = 0; 1194 if (c == '{') { 1195 bracketed_name = 1; 1196 c = pgetc(); 1197 if (c == '#') { 1198 if ((c = pgetc()) == '}') 1199 c = '#'; 1200 else 1201 subtype = VSLENGTH; 1202 } 1203 else 1204 subtype = 0; 1205 } 1206 if (!is_eof(c) && is_name(c)) { 1207 length = 0; 1208 do { 1209 STPUTC(c, out); 1210 c = pgetc(); 1211 length++; 1212 } while (!is_eof(c) && is_in_name(c)); 1213 if (length == 6 && 1214 strncmp(out - length, "LINENO", length) == 0) { 1215 /* Replace the variable name with the 1216 * current line number. */ 1217 linno = plinno; 1218 if (funclinno != 0) 1219 linno -= funclinno - 1; 1220 snprintf(buf, sizeof(buf), "%d", linno); 1221 STADJUST(-6, out); 1222 for (i = 0; buf[i] != '\0'; i++) 1223 STPUTC(buf[i], out); 1224 flags |= VSLINENO; 1225 } 1226 } else if (is_digit(c)) { 1227 if (bracketed_name) { 1228 do { 1229 STPUTC(c, out); 1230 c = pgetc(); 1231 } while (is_digit(c)); 1232 } else { 1233 STPUTC(c, out); 1234 c = pgetc(); 1235 } 1236 } else { 1237 if (! is_special(c)) { 1238 subtype = VSERROR; 1239 if (c == '}') 1240 pungetc(); 1241 else 1242 USTPUTC(c, out); 1243 } else { 1244 USTPUTC(c, out); 1245 c = pgetc(); 1246 } 1247 } 1248 if (subtype == 0) { 1249 switch (c) { 1250 case ':': 1251 flags |= VSNUL; 1252 c = pgetc(); 1253 /*FALLTHROUGH*/ 1254 default: 1255 p = strchr(types, c); 1256 if (p == NULL) { 1257 if (flags == VSNUL) 1258 STPUTC(':', out); 1259 STPUTC(c, out); 1260 subtype = VSERROR; 1261 } else 1262 subtype = p - types + VSNORMAL; 1263 break; 1264 case '%': 1265 case '#': 1266 { 1267 int cc = c; 1268 subtype = c == '#' ? VSTRIMLEFT : 1269 VSTRIMRIGHT; 1270 c = pgetc(); 1271 if (c == cc) 1272 subtype++; 1273 else 1274 pungetc(); 1275 break; 1276 } 1277 } 1278 } else if (subtype != VSERROR) { 1279 pungetc(); 1280 } 1281 STPUTC('=', out); 1282 if (subtype != VSLENGTH && (dblquote || arinest)) 1283 flags |= VSQUOTE; 1284 *(stackblock() + typeloc) = subtype | flags; 1285 if (subtype != VSNORMAL) 1286 varnest++; 1287 } 1288 goto parsesub_return; 1289 } 1290 1291 1292 /* 1293 * Called to parse command substitutions. Newstyle is set if the command 1294 * is enclosed inside $(...); nlpp is a pointer to the head of the linked 1295 * list of commands (passed by reference), and savelen is the number of 1296 * characters on the top of the stack which must be preserved. 1297 */ 1298 1299 parsebackq: { 1300 struct nodelist **nlpp; 1301 int savepbq; 1302 union node *n; 1303 char *volatile str; 1304 struct jmploc jmploc; 1305 struct jmploc *volatile savehandler; 1306 int savelen; 1307 volatile int saveprompt; 1308 1309 savepbq = parsebackquote; 1310 if (setjmp(jmploc.loc)) { 1311 if (str) 1312 ckfree(str); 1313 parsebackquote = 0; 1314 handler = savehandler; 1315 longjmp(handler->loc, 1); 1316 } 1317 INTOFF; 1318 str = NULL; 1319 savelen = out - stackblock(); 1320 if (savelen > 0) { 1321 str = ckmalloc(savelen); 1322 memcpy(str, stackblock(), savelen); 1323 } 1324 savehandler = handler; 1325 handler = &jmploc; 1326 INTON; 1327 if (oldstyle) { 1328 /* We must read until the closing backquote, giving special 1329 treatment to some slashes, and then push the string and 1330 reread it as input, interpreting it normally. */ 1331 char *pout; 1332 int pc; 1333 int psavelen; 1334 char *pstr; 1335 1336 1337 STARTSTACKSTR(pout); 1338 for (;;) { 1339 if (needprompt) { 1340 setprompt(2); 1341 needprompt = 0; 1342 } 1343 switch (pc = pgetc()) { 1344 case '`': 1345 goto done; 1346 1347 case '\\': 1348 if ((pc = pgetc()) == '\n') { 1349 plinno++; 1350 if (doprompt) 1351 setprompt(2); 1352 else 1353 setprompt(0); 1354 /* 1355 * If eating a newline, avoid putting 1356 * the newline into the new character 1357 * stream (via the STPUTC after the 1358 * switch). 1359 */ 1360 continue; 1361 } 1362 if (pc != '\\' && pc != '`' && pc != '$' 1363 && (!dblquote || pc != '"')) 1364 STPUTC('\\', pout); 1365 break; 1366 1367 case '\n': 1368 plinno++; 1369 needprompt = doprompt; 1370 break; 1371 1372 case PEOF: 1373 startlinno = plinno; 1374 synerror("EOF in backquote substitution"); 1375 break; 1376 1377 default: 1378 break; 1379 } 1380 STPUTC(pc, pout); 1381 } 1382 done: 1383 STPUTC('\0', pout); 1384 psavelen = pout - stackblock(); 1385 if (psavelen > 0) { 1386 pstr = ckmalloc(psavelen); 1387 memcpy(pstr, stackblock(), psavelen); 1388 setinputstring(pstr, 1); 1389 } 1390 } 1391 nlpp = &bqlist; 1392 while (*nlpp) 1393 nlpp = &(*nlpp)->next; 1394 *nlpp = (struct nodelist *)stalloc(sizeof (struct nodelist)); 1395 (*nlpp)->next = NULL; 1396 parsebackquote = oldstyle; 1397 1398 if (oldstyle) { 1399 saveprompt = doprompt; 1400 doprompt = 0; 1401 } 1402 1403 n = list(0); 1404 1405 if (oldstyle) 1406 doprompt = saveprompt; 1407 else { 1408 if (readtoken() != TRP) 1409 synexpect(TRP); 1410 } 1411 1412 (*nlpp)->n = n; 1413 if (oldstyle) { 1414 /* 1415 * Start reading from old file again, ignoring any pushed back 1416 * tokens left from the backquote parsing 1417 */ 1418 popfile(); 1419 tokpushback = 0; 1420 } 1421 while (stackblocksize() <= savelen) 1422 growstackblock(); 1423 STARTSTACKSTR(out); 1424 if (str) { 1425 memcpy(out, str, savelen); 1426 STADJUST(savelen, out); 1427 INTOFF; 1428 ckfree(str); 1429 str = NULL; 1430 INTON; 1431 } 1432 parsebackquote = savepbq; 1433 handler = savehandler; 1434 if (arinest || dblquote) 1435 USTPUTC(CTLBACKQ | CTLQUOTE, out); 1436 else 1437 USTPUTC(CTLBACKQ, out); 1438 if (oldstyle) 1439 goto parsebackq_oldreturn; 1440 else 1441 goto parsebackq_newreturn; 1442 } 1443 1444 /* 1445 * Parse an arithmetic expansion (indicate start of one and set state) 1446 */ 1447 parsearith: { 1448 1449 if (++arinest == 1) { 1450 prevsyntax = syntax; 1451 syntax = ARISYNTAX; 1452 USTPUTC(CTLARI, out); 1453 if (dblquote) 1454 USTPUTC('"',out); 1455 else 1456 USTPUTC(' ',out); 1457 } else { 1458 /* 1459 * we collapse embedded arithmetic expansion to 1460 * parenthesis, which should be equivalent 1461 */ 1462 USTPUTC('(', out); 1463 } 1464 goto parsearith_return; 1465 } 1466 1467 } /* end of readtoken */ 1468 1469 1470 1471 #ifdef mkinit 1472 RESET { 1473 tokpushback = 0; 1474 checkkwd = 0; 1475 } 1476 #endif 1477 1478 /* 1479 * Returns true if the text contains nothing to expand (no dollar signs 1480 * or backquotes). 1481 */ 1482 1483 STATIC int 1484 noexpand(char *text) 1485 { 1486 char *p; 1487 char c; 1488 1489 p = text; 1490 while ((c = *p++) != '\0') { 1491 if ( c == CTLQUOTEMARK) 1492 continue; 1493 if (c == CTLESC) 1494 p++; 1495 else if (BASESYNTAX[(int)c] == CCTL) 1496 return 0; 1497 } 1498 return 1; 1499 } 1500 1501 1502 /* 1503 * Return true if the argument is a legal variable name (a letter or 1504 * underscore followed by zero or more letters, underscores, and digits). 1505 */ 1506 1507 int 1508 goodname(char *name) 1509 { 1510 char *p; 1511 1512 p = name; 1513 if (! is_name(*p)) 1514 return 0; 1515 while (*++p) { 1516 if (! is_in_name(*p)) 1517 return 0; 1518 } 1519 return 1; 1520 } 1521 1522 1523 /* 1524 * Called when an unexpected token is read during the parse. The argument 1525 * is the token that is expected, or -1 if more than one type of token can 1526 * occur at this point. 1527 */ 1528 1529 STATIC void 1530 synexpect(int token) 1531 { 1532 char msg[64]; 1533 1534 if (token >= 0) { 1535 fmtstr(msg, 64, "%s unexpected (expecting %s)", 1536 tokname[lasttoken], tokname[token]); 1537 } else { 1538 fmtstr(msg, 64, "%s unexpected", tokname[lasttoken]); 1539 } 1540 synerror(msg); 1541 } 1542 1543 1544 STATIC void 1545 synerror(const char *msg) 1546 { 1547 if (commandname) 1548 outfmt(&errout, "%s: %d: ", commandname, startlinno); 1549 outfmt(&errout, "Syntax error: %s\n", msg); 1550 error(NULL); 1551 } 1552 1553 STATIC void 1554 setprompt(int which) 1555 { 1556 whichprompt = which; 1557 1558 #ifndef NO_HISTORY 1559 if (!el) 1560 #endif 1561 out2str(getprompt(NULL)); 1562 } 1563 1564 /* 1565 * called by editline -- any expansions to the prompt 1566 * should be added here. 1567 */ 1568 const char * 1569 getprompt(void *unused __unused) 1570 { 1571 static char ps[PROMPTLEN]; 1572 const char *fmt; 1573 int i, j, trim; 1574 1575 /* 1576 * Select prompt format. 1577 */ 1578 switch (whichprompt) { 1579 case 0: 1580 fmt = ""; 1581 break; 1582 case 1: 1583 fmt = ps1val(); 1584 break; 1585 case 2: 1586 fmt = ps2val(); 1587 break; 1588 default: 1589 return "<internal prompt error>"; 1590 } 1591 1592 /* 1593 * Format prompt string. 1594 */ 1595 for (i = 0; (i < 127) && (*fmt != '\0'); i++, fmt++) 1596 if (*fmt == '\\') 1597 switch (*++fmt) { 1598 1599 /* 1600 * Hostname. 1601 * 1602 * \h specifies just the local hostname, 1603 * \H specifies fully-qualified hostname. 1604 */ 1605 case 'h': 1606 case 'H': 1607 ps[i] = '\0'; 1608 gethostname(&ps[i], PROMPTLEN - i); 1609 /* Skip to end of hostname. */ 1610 trim = (*fmt == 'h') ? '.' : '\0'; 1611 while ((ps[i+1] != '\0') && (ps[i+1] != trim)) 1612 i++; 1613 break; 1614 1615 /* 1616 * Working directory. 1617 * 1618 * \W specifies just the final component, 1619 * \w specifies the entire path. 1620 */ 1621 case 'W': 1622 case 'w': 1623 ps[i] = '\0'; 1624 getcwd(&ps[i], PROMPTLEN - i); 1625 if (*fmt == 'W') { 1626 /* Final path component only. */ 1627 trim = 1; 1628 for (j = i; ps[j] != '\0'; j++) 1629 if (ps[j] == '/') 1630 trim = j + 1; 1631 memmove(&ps[i], &ps[trim], 1632 j - trim + 1); 1633 } 1634 /* Skip to end of path. */ 1635 while (ps[i + 1] != '\0') 1636 i++; 1637 break; 1638 1639 /* 1640 * Superuser status. 1641 * 1642 * '$' for normal users, '#' for root. 1643 */ 1644 case '$': 1645 ps[i] = (geteuid() != 0) ? '$' : '#'; 1646 break; 1647 1648 /* 1649 * A literal \. 1650 */ 1651 case '\\': 1652 ps[i] = '\\'; 1653 break; 1654 1655 /* 1656 * Emit unrecognized formats verbatim. 1657 */ 1658 default: 1659 ps[i++] = '\\'; 1660 ps[i] = *fmt; 1661 break; 1662 } 1663 else 1664 ps[i] = *fmt; 1665 ps[i] = '\0'; 1666 return (ps); 1667 } 1668