1 /*- 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * Copyright (c) 1997-2005 5 * Herbert Xu <herbert@gondor.apana.org.au>. 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 * 4. 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 #ifndef lint 36 #if 0 37 static char sccsid[] = "@(#)expand.c 8.5 (Berkeley) 5/15/95"; 38 #endif 39 #endif /* not lint */ 40 #include <sys/cdefs.h> 41 __FBSDID("$FreeBSD$"); 42 43 #include <sys/types.h> 44 #include <sys/time.h> 45 #include <sys/stat.h> 46 #include <errno.h> 47 #include <dirent.h> 48 #include <unistd.h> 49 #include <pwd.h> 50 #include <stdlib.h> 51 #include <limits.h> 52 #include <stdio.h> 53 #include <string.h> 54 55 /* 56 * Routines to expand arguments to commands. We have to deal with 57 * backquotes, shell variables, and file metacharacters. 58 */ 59 60 #include "shell.h" 61 #include "main.h" 62 #include "nodes.h" 63 #include "eval.h" 64 #include "expand.h" 65 #include "syntax.h" 66 #include "parser.h" 67 #include "jobs.h" 68 #include "options.h" 69 #include "var.h" 70 #include "input.h" 71 #include "output.h" 72 #include "memalloc.h" 73 #include "error.h" 74 #include "mystring.h" 75 #include "arith.h" 76 #include "show.h" 77 78 /* 79 * Structure specifying which parts of the string should be searched 80 * for IFS characters. 81 */ 82 83 struct ifsregion { 84 struct ifsregion *next; /* next region in list */ 85 int begoff; /* offset of start of region */ 86 int endoff; /* offset of end of region */ 87 int inquotes; /* search for nul bytes only */ 88 }; 89 90 91 STATIC char *expdest; /* output of current string */ 92 STATIC struct nodelist *argbackq; /* list of back quote expressions */ 93 STATIC struct ifsregion ifsfirst; /* first struct in list of ifs regions */ 94 STATIC struct ifsregion *ifslastp; /* last struct in list */ 95 STATIC struct arglist exparg; /* holds expanded arg list */ 96 97 STATIC void argstr(char *, int); 98 STATIC char *exptilde(char *, int); 99 STATIC void expbackq(union node *, int, int); 100 STATIC int subevalvar(char *, char *, int, int, int, int); 101 STATIC char *evalvar(char *, int); 102 STATIC int varisset(char *, int); 103 STATIC void varvalue(char *, int, int, int); 104 STATIC void recordregion(int, int, int); 105 STATIC void removerecordregions(int); 106 STATIC void ifsbreakup(char *, struct arglist *); 107 STATIC void expandmeta(struct strlist *, int); 108 STATIC void expmeta(char *, char *); 109 STATIC void addfname(char *); 110 STATIC struct strlist *expsort(struct strlist *); 111 STATIC struct strlist *msort(struct strlist *, int); 112 STATIC int pmatch(const char *, const char *, int); 113 STATIC char *cvtnum(int, char *); 114 STATIC int collate_range_cmp(int, int); 115 116 STATIC int 117 collate_range_cmp(int c1, int c2) 118 { 119 static char s1[2], s2[2]; 120 121 s1[0] = c1; 122 s2[0] = c2; 123 return (strcoll(s1, s2)); 124 } 125 126 /* 127 * Expand shell variables and backquotes inside a here document. 128 * union node *arg the document 129 * int fd; where to write the expanded version 130 */ 131 132 void 133 expandhere(union node *arg, int fd) 134 { 135 herefd = fd; 136 expandarg(arg, (struct arglist *)NULL, 0); 137 xwrite(fd, stackblock(), expdest - stackblock()); 138 } 139 140 141 /* 142 * Perform variable substitution and command substitution on an argument, 143 * placing the resulting list of arguments in arglist. If EXP_FULL is true, 144 * perform splitting and file name expansion. When arglist is NULL, perform 145 * here document expansion. 146 */ 147 148 void 149 expandarg(union node *arg, struct arglist *arglist, int flag) 150 { 151 struct strlist *sp; 152 char *p; 153 154 argbackq = arg->narg.backquote; 155 STARTSTACKSTR(expdest); 156 ifsfirst.next = NULL; 157 ifslastp = NULL; 158 argstr(arg->narg.text, flag); 159 if (arglist == NULL) { 160 return; /* here document expanded */ 161 } 162 STPUTC('\0', expdest); 163 p = grabstackstr(expdest); 164 exparg.lastp = &exparg.list; 165 /* 166 * TODO - EXP_REDIR 167 */ 168 if (flag & EXP_FULL) { 169 ifsbreakup(p, &exparg); 170 *exparg.lastp = NULL; 171 exparg.lastp = &exparg.list; 172 expandmeta(exparg.list, flag); 173 } else { 174 if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */ 175 rmescapes(p); 176 sp = (struct strlist *)stalloc(sizeof (struct strlist)); 177 sp->text = p; 178 *exparg.lastp = sp; 179 exparg.lastp = &sp->next; 180 } 181 while (ifsfirst.next != NULL) { 182 struct ifsregion *ifsp; 183 INTOFF; 184 ifsp = ifsfirst.next->next; 185 ckfree(ifsfirst.next); 186 ifsfirst.next = ifsp; 187 INTON; 188 } 189 *exparg.lastp = NULL; 190 if (exparg.list) { 191 *arglist->lastp = exparg.list; 192 arglist->lastp = exparg.lastp; 193 } 194 } 195 196 197 198 /* 199 * Perform variable and command substitution. If EXP_FULL is set, output CTLESC 200 * characters to allow for further processing. Otherwise treat 201 * $@ like $* since no splitting will be performed. 202 */ 203 204 STATIC void 205 argstr(char *p, int flag) 206 { 207 char c; 208 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); /* do CTLESC */ 209 int firsteq = 1; 210 211 if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE))) 212 p = exptilde(p, flag); 213 for (;;) { 214 switch (c = *p++) { 215 case '\0': 216 case CTLENDVAR: /* ??? */ 217 goto breakloop; 218 case CTLQUOTEMARK: 219 /* "$@" syntax adherence hack */ 220 if (p[0] == CTLVAR && p[2] == '@' && p[3] == '=') 221 break; 222 if ((flag & EXP_FULL) != 0) 223 STPUTC(c, expdest); 224 break; 225 case CTLESC: 226 if (quotes) 227 STPUTC(c, expdest); 228 c = *p++; 229 STPUTC(c, expdest); 230 break; 231 case CTLVAR: 232 p = evalvar(p, flag); 233 break; 234 case CTLBACKQ: 235 case CTLBACKQ|CTLQUOTE: 236 expbackq(argbackq->n, c & CTLQUOTE, flag); 237 argbackq = argbackq->next; 238 break; 239 case CTLENDARI: 240 expari(flag); 241 break; 242 case ':': 243 case '=': 244 /* 245 * sort of a hack - expand tildes in variable 246 * assignments (after the first '=' and after ':'s). 247 */ 248 STPUTC(c, expdest); 249 if (flag & EXP_VARTILDE && *p == '~') { 250 if (c == '=') { 251 if (firsteq) 252 firsteq = 0; 253 else 254 break; 255 } 256 p = exptilde(p, flag); 257 } 258 break; 259 default: 260 STPUTC(c, expdest); 261 } 262 } 263 breakloop:; 264 } 265 266 STATIC char * 267 exptilde(char *p, int flag) 268 { 269 char c, *startp = p; 270 struct passwd *pw; 271 char *home; 272 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 273 274 while ((c = *p) != '\0') { 275 switch(c) { 276 case CTLESC: /* This means CTL* are always considered quoted. */ 277 case CTLVAR: 278 case CTLBACKQ: 279 case CTLBACKQ | CTLQUOTE: 280 case CTLARI: 281 case CTLENDARI: 282 case CTLQUOTEMARK: 283 return (startp); 284 case ':': 285 if (flag & EXP_VARTILDE) 286 goto done; 287 break; 288 case '/': 289 case CTLENDVAR: 290 goto done; 291 } 292 p++; 293 } 294 done: 295 *p = '\0'; 296 if (*(startp+1) == '\0') { 297 if ((home = lookupvar("HOME")) == NULL) 298 goto lose; 299 } else { 300 if ((pw = getpwnam(startp+1)) == NULL) 301 goto lose; 302 home = pw->pw_dir; 303 } 304 if (*home == '\0') 305 goto lose; 306 *p = c; 307 while ((c = *home++) != '\0') { 308 if (quotes && SQSYNTAX[(int)c] == CCTL) 309 STPUTC(CTLESC, expdest); 310 STPUTC(c, expdest); 311 } 312 return (p); 313 lose: 314 *p = c; 315 return (startp); 316 } 317 318 319 STATIC void 320 removerecordregions(int endoff) 321 { 322 if (ifslastp == NULL) 323 return; 324 325 if (ifsfirst.endoff > endoff) { 326 while (ifsfirst.next != NULL) { 327 struct ifsregion *ifsp; 328 INTOFF; 329 ifsp = ifsfirst.next->next; 330 ckfree(ifsfirst.next); 331 ifsfirst.next = ifsp; 332 INTON; 333 } 334 if (ifsfirst.begoff > endoff) 335 ifslastp = NULL; 336 else { 337 ifslastp = &ifsfirst; 338 ifsfirst.endoff = endoff; 339 } 340 return; 341 } 342 343 ifslastp = &ifsfirst; 344 while (ifslastp->next && ifslastp->next->begoff < endoff) 345 ifslastp=ifslastp->next; 346 while (ifslastp->next != NULL) { 347 struct ifsregion *ifsp; 348 INTOFF; 349 ifsp = ifslastp->next->next; 350 ckfree(ifslastp->next); 351 ifslastp->next = ifsp; 352 INTON; 353 } 354 if (ifslastp->endoff > endoff) 355 ifslastp->endoff = endoff; 356 } 357 358 /* 359 * Expand arithmetic expression. Backup to start of expression, 360 * evaluate, place result in (backed up) result, adjust string position. 361 */ 362 void 363 expari(int flag) 364 { 365 char *p, *q, *start; 366 arith_t result; 367 int begoff; 368 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 369 int quoted; 370 371 372 /* 373 * This routine is slightly over-complicated for 374 * efficiency. First we make sure there is 375 * enough space for the result, which may be bigger 376 * than the expression if we add exponentiation. Next we 377 * scan backwards looking for the start of arithmetic. If the 378 * next previous character is a CTLESC character, then we 379 * have to rescan starting from the beginning since CTLESC 380 * characters have to be processed left to right. 381 */ 382 CHECKSTRSPACE(DIGITS(result) - 2, expdest); 383 USTPUTC('\0', expdest); 384 start = stackblock(); 385 p = expdest - 2; 386 while (p >= start && *p != CTLARI) 387 --p; 388 if (p < start || *p != CTLARI) 389 error("missing CTLARI (shouldn't happen)"); 390 if (p > start && *(p - 1) == CTLESC) 391 for (p = start; *p != CTLARI; p++) 392 if (*p == CTLESC) 393 p++; 394 395 if (p[1] == '"') 396 quoted=1; 397 else 398 quoted=0; 399 begoff = p - start; 400 removerecordregions(begoff); 401 if (quotes) 402 rmescapes(p+2); 403 q = grabstackstr(expdest); 404 result = arith(p+2); 405 ungrabstackstr(q, expdest); 406 fmtstr(p, DIGITS(result), ARITH_FORMAT_STR, result); 407 while (*p++) 408 ; 409 if (quoted == 0) 410 recordregion(begoff, p - 1 - start, 0); 411 result = expdest - p + 1; 412 STADJUST(-result, expdest); 413 } 414 415 416 /* 417 * Expand stuff in backwards quotes. 418 */ 419 420 STATIC void 421 expbackq(union node *cmd, int quoted, int flag) 422 { 423 struct backcmd in; 424 int i; 425 char buf[128]; 426 char *p; 427 char *dest = expdest; 428 struct ifsregion saveifs, *savelastp; 429 struct nodelist *saveargbackq; 430 char lastc; 431 int startloc = dest - stackblock(); 432 char const *syntax = quoted? DQSYNTAX : BASESYNTAX; 433 int saveherefd; 434 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 435 int nnl; 436 437 INTOFF; 438 saveifs = ifsfirst; 439 savelastp = ifslastp; 440 saveargbackq = argbackq; 441 saveherefd = herefd; 442 herefd = -1; 443 p = grabstackstr(dest); 444 evalbackcmd(cmd, &in); 445 ungrabstackstr(p, dest); 446 ifsfirst = saveifs; 447 ifslastp = savelastp; 448 argbackq = saveargbackq; 449 herefd = saveherefd; 450 451 p = in.buf; 452 lastc = '\0'; 453 nnl = 0; 454 /* Don't copy trailing newlines */ 455 for (;;) { 456 if (--in.nleft < 0) { 457 if (in.fd < 0) 458 break; 459 while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR); 460 TRACE(("expbackq: read returns %d\n", i)); 461 if (i <= 0) 462 break; 463 p = buf; 464 in.nleft = i - 1; 465 } 466 lastc = *p++; 467 if (lastc != '\0') { 468 if (quotes && syntax[(int)lastc] == CCTL) 469 STPUTC(CTLESC, dest); 470 if (lastc == '\n') { 471 nnl++; 472 } else { 473 while (nnl > 0) { 474 nnl--; 475 STPUTC('\n', dest); 476 } 477 STPUTC(lastc, dest); 478 } 479 } 480 } 481 482 if (in.fd >= 0) 483 close(in.fd); 484 if (in.buf) 485 ckfree(in.buf); 486 if (in.jp) 487 exitstatus = waitforjob(in.jp, (int *)NULL); 488 if (quoted == 0) 489 recordregion(startloc, dest - stackblock(), 0); 490 TRACE(("evalbackq: size=%d: \"%.*s\"\n", 491 (dest - stackblock()) - startloc, 492 (dest - stackblock()) - startloc, 493 stackblock() + startloc)); 494 expdest = dest; 495 INTON; 496 } 497 498 499 500 STATIC int 501 subevalvar(char *p, char *str, int strloc, int subtype, int startloc, 502 int varflags) 503 { 504 char *startp; 505 char *loc = NULL; 506 char *q; 507 int c = 0; 508 int saveherefd = herefd; 509 struct nodelist *saveargbackq = argbackq; 510 int amount; 511 512 herefd = -1; 513 argstr(p, (subtype == VSTRIMLEFT || subtype == VSTRIMLEFTMAX || 514 subtype == VSTRIMRIGHT || subtype == VSTRIMRIGHTMAX ? 515 EXP_CASE : 0) | EXP_TILDE); 516 STACKSTRNUL(expdest); 517 herefd = saveherefd; 518 argbackq = saveargbackq; 519 startp = stackblock() + startloc; 520 if (str == NULL) 521 str = stackblock() + strloc; 522 523 switch (subtype) { 524 case VSASSIGN: 525 setvar(str, startp, 0); 526 amount = startp - expdest; 527 STADJUST(amount, expdest); 528 varflags &= ~VSNUL; 529 if (c != 0) 530 *loc = c; 531 return 1; 532 533 case VSQUESTION: 534 if (*p != CTLENDVAR) { 535 outfmt(out2, "%s\n", startp); 536 error((char *)NULL); 537 } 538 error("%.*s: parameter %snot set", (int)(p - str - 1), 539 str, (varflags & VSNUL) ? "null or " 540 : nullstr); 541 return 0; 542 543 case VSTRIMLEFT: 544 for (loc = startp; loc < str; loc++) { 545 c = *loc; 546 *loc = '\0'; 547 if (patmatch(str, startp, varflags & VSQUOTE)) { 548 *loc = c; 549 goto recordleft; 550 } 551 *loc = c; 552 if ((varflags & VSQUOTE) && *loc == CTLESC) 553 loc++; 554 } 555 return 0; 556 557 case VSTRIMLEFTMAX: 558 for (loc = str - 1; loc >= startp;) { 559 c = *loc; 560 *loc = '\0'; 561 if (patmatch(str, startp, varflags & VSQUOTE)) { 562 *loc = c; 563 goto recordleft; 564 } 565 *loc = c; 566 loc--; 567 if ((varflags & VSQUOTE) && loc > startp && 568 *(loc - 1) == CTLESC) { 569 for (q = startp; q < loc; q++) 570 if (*q == CTLESC) 571 q++; 572 if (q > loc) 573 loc--; 574 } 575 } 576 return 0; 577 578 case VSTRIMRIGHT: 579 for (loc = str - 1; loc >= startp;) { 580 if (patmatch(str, loc, varflags & VSQUOTE)) { 581 amount = loc - expdest; 582 STADJUST(amount, expdest); 583 return 1; 584 } 585 loc--; 586 if ((varflags & VSQUOTE) && loc > startp && 587 *(loc - 1) == CTLESC) { 588 for (q = startp; q < loc; q++) 589 if (*q == CTLESC) 590 q++; 591 if (q > loc) 592 loc--; 593 } 594 } 595 return 0; 596 597 case VSTRIMRIGHTMAX: 598 for (loc = startp; loc < str - 1; loc++) { 599 if (patmatch(str, loc, varflags & VSQUOTE)) { 600 amount = loc - expdest; 601 STADJUST(amount, expdest); 602 return 1; 603 } 604 if ((varflags & VSQUOTE) && *loc == CTLESC) 605 loc++; 606 } 607 return 0; 608 609 610 default: 611 abort(); 612 } 613 614 recordleft: 615 amount = ((str - 1) - (loc - startp)) - expdest; 616 STADJUST(amount, expdest); 617 while (loc != str - 1) 618 *startp++ = *loc++; 619 return 1; 620 } 621 622 623 /* 624 * Expand a variable, and return a pointer to the next character in the 625 * input string. 626 */ 627 628 STATIC char * 629 evalvar(char *p, int flag) 630 { 631 int subtype; 632 int varflags; 633 char *var; 634 char *val; 635 int patloc; 636 int c; 637 int set; 638 int special; 639 int startloc; 640 int varlen; 641 int easy; 642 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 643 644 varflags = (unsigned char)*p++; 645 subtype = varflags & VSTYPE; 646 var = p; 647 special = 0; 648 if (! is_name(*p)) 649 special = 1; 650 p = strchr(p, '=') + 1; 651 again: /* jump here after setting a variable with ${var=text} */ 652 if (varflags & VSLINENO) { 653 set = 1; 654 special = 0; 655 val = var; 656 p[-1] = '\0'; /* temporarily overwrite '=' to have \0 657 terminated string */ 658 } else if (special) { 659 set = varisset(var, varflags & VSNUL); 660 val = NULL; 661 } else { 662 val = bltinlookup(var, 1); 663 if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) { 664 val = NULL; 665 set = 0; 666 } else 667 set = 1; 668 } 669 varlen = 0; 670 startloc = expdest - stackblock(); 671 if (!set && uflag && *var != '@' && *var != '*') { 672 switch (subtype) { 673 case VSNORMAL: 674 case VSTRIMLEFT: 675 case VSTRIMLEFTMAX: 676 case VSTRIMRIGHT: 677 case VSTRIMRIGHTMAX: 678 case VSLENGTH: 679 error("%.*s: parameter not set", (int)(p - var - 1), 680 var); 681 } 682 } 683 if (set && subtype != VSPLUS) { 684 /* insert the value of the variable */ 685 if (special) { 686 varvalue(var, varflags & VSQUOTE, subtype, flag); 687 if (subtype == VSLENGTH) { 688 varlen = expdest - stackblock() - startloc; 689 STADJUST(-varlen, expdest); 690 } 691 } else { 692 char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX 693 : BASESYNTAX; 694 695 if (subtype == VSLENGTH) { 696 for (;*val; val++) 697 varlen++; 698 } 699 else { 700 while (*val) { 701 if (quotes && 702 syntax[(int)*val] == CCTL) 703 STPUTC(CTLESC, expdest); 704 STPUTC(*val++, expdest); 705 } 706 707 } 708 } 709 } 710 711 if (subtype == VSPLUS) 712 set = ! set; 713 714 easy = ((varflags & VSQUOTE) == 0 || 715 (*var == '@' && shellparam.nparam != 1)); 716 717 718 switch (subtype) { 719 case VSLENGTH: 720 expdest = cvtnum(varlen, expdest); 721 goto record; 722 723 case VSNORMAL: 724 if (!easy) 725 break; 726 record: 727 recordregion(startloc, expdest - stackblock(), 728 varflags & VSQUOTE); 729 break; 730 731 case VSPLUS: 732 case VSMINUS: 733 if (!set) { 734 argstr(p, flag); 735 break; 736 } 737 if (easy) 738 goto record; 739 break; 740 741 case VSTRIMLEFT: 742 case VSTRIMLEFTMAX: 743 case VSTRIMRIGHT: 744 case VSTRIMRIGHTMAX: 745 if (!set) 746 break; 747 /* 748 * Terminate the string and start recording the pattern 749 * right after it 750 */ 751 STPUTC('\0', expdest); 752 patloc = expdest - stackblock(); 753 if (subevalvar(p, NULL, patloc, subtype, 754 startloc, varflags) == 0) { 755 int amount = (expdest - stackblock() - patloc) + 1; 756 STADJUST(-amount, expdest); 757 } 758 /* Remove any recorded regions beyond start of variable */ 759 removerecordregions(startloc); 760 goto record; 761 762 case VSASSIGN: 763 case VSQUESTION: 764 if (!set) { 765 if (subevalvar(p, var, 0, subtype, startloc, varflags)) { 766 varflags &= ~VSNUL; 767 /* 768 * Remove any recorded regions beyond 769 * start of variable 770 */ 771 removerecordregions(startloc); 772 goto again; 773 } 774 break; 775 } 776 if (easy) 777 goto record; 778 break; 779 780 case VSERROR: 781 c = p - var - 1; 782 error("${%.*s%s}: Bad substitution", c, var, 783 (c > 0 && *p != CTLENDVAR) ? "..." : ""); 784 785 default: 786 abort(); 787 } 788 p[-1] = '='; /* recover overwritten '=' */ 789 790 if (subtype != VSNORMAL) { /* skip to end of alternative */ 791 int nesting = 1; 792 for (;;) { 793 if ((c = *p++) == CTLESC) 794 p++; 795 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { 796 if (set) 797 argbackq = argbackq->next; 798 } else if (c == CTLVAR) { 799 if ((*p++ & VSTYPE) != VSNORMAL) 800 nesting++; 801 } else if (c == CTLENDVAR) { 802 if (--nesting == 0) 803 break; 804 } 805 } 806 } 807 return p; 808 } 809 810 811 812 /* 813 * Test whether a specialized variable is set. 814 */ 815 816 STATIC int 817 varisset(char *name, int nulok) 818 { 819 820 if (*name == '!') 821 return backgndpid != -1; 822 else if (*name == '@' || *name == '*') { 823 if (*shellparam.p == NULL) 824 return 0; 825 826 if (nulok) { 827 char **av; 828 829 for (av = shellparam.p; *av; av++) 830 if (**av != '\0') 831 return 1; 832 return 0; 833 } 834 } else if (is_digit(*name)) { 835 char *ap; 836 int num = atoi(name); 837 838 if (num > shellparam.nparam) 839 return 0; 840 841 if (num == 0) 842 ap = arg0; 843 else 844 ap = shellparam.p[num - 1]; 845 846 if (nulok && (ap == NULL || *ap == '\0')) 847 return 0; 848 } 849 return 1; 850 } 851 852 853 854 /* 855 * Add the value of a specialized variable to the stack string. 856 */ 857 858 STATIC void 859 varvalue(char *name, int quoted, int subtype, int flag) 860 { 861 int num; 862 char *p; 863 int i; 864 char sep; 865 char **ap; 866 char const *syntax; 867 868 #define STRTODEST(p) \ 869 do {\ 870 if (flag & (EXP_FULL | EXP_CASE) && subtype != VSLENGTH) { \ 871 syntax = quoted? DQSYNTAX : BASESYNTAX; \ 872 while (*p) { \ 873 if (syntax[(int)*p] == CCTL) \ 874 STPUTC(CTLESC, expdest); \ 875 STPUTC(*p++, expdest); \ 876 } \ 877 } else \ 878 while (*p) \ 879 STPUTC(*p++, expdest); \ 880 } while (0) 881 882 883 switch (*name) { 884 case '$': 885 num = rootpid; 886 goto numvar; 887 case '?': 888 num = oexitstatus; 889 goto numvar; 890 case '#': 891 num = shellparam.nparam; 892 goto numvar; 893 case '!': 894 num = backgndpid; 895 numvar: 896 expdest = cvtnum(num, expdest); 897 break; 898 case '-': 899 for (i = 0 ; i < NOPTS ; i++) { 900 if (optlist[i].val) 901 STPUTC(optlist[i].letter, expdest); 902 } 903 break; 904 case '@': 905 if (flag & EXP_FULL && quoted) { 906 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 907 STRTODEST(p); 908 if (*ap) 909 STPUTC('\0', expdest); 910 } 911 break; 912 } 913 /* FALLTHROUGH */ 914 case '*': 915 if (ifsset()) 916 sep = ifsval()[0]; 917 else 918 sep = ' '; 919 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 920 STRTODEST(p); 921 if (*ap && sep) 922 STPUTC(sep, expdest); 923 } 924 break; 925 case '0': 926 p = arg0; 927 STRTODEST(p); 928 break; 929 default: 930 if (is_digit(*name)) { 931 num = atoi(name); 932 if (num > 0 && num <= shellparam.nparam) { 933 p = shellparam.p[num - 1]; 934 STRTODEST(p); 935 } 936 } 937 break; 938 } 939 } 940 941 942 943 /* 944 * Record the the fact that we have to scan this region of the 945 * string for IFS characters. 946 */ 947 948 STATIC void 949 recordregion(int start, int end, int inquotes) 950 { 951 struct ifsregion *ifsp; 952 953 if (ifslastp == NULL) { 954 ifsp = &ifsfirst; 955 } else { 956 if (ifslastp->endoff == start 957 && ifslastp->inquotes == inquotes) { 958 /* extend previous area */ 959 ifslastp->endoff = end; 960 return; 961 } 962 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 963 ifslastp->next = ifsp; 964 } 965 ifslastp = ifsp; 966 ifslastp->next = NULL; 967 ifslastp->begoff = start; 968 ifslastp->endoff = end; 969 ifslastp->inquotes = inquotes; 970 } 971 972 973 974 /* 975 * Break the argument string into pieces based upon IFS and add the 976 * strings to the argument list. The regions of the string to be 977 * searched for IFS characters have been stored by recordregion. 978 */ 979 STATIC void 980 ifsbreakup(char *string, struct arglist *arglist) 981 { 982 struct ifsregion *ifsp; 983 struct strlist *sp; 984 char *start; 985 char *p; 986 char *q; 987 const char *ifs; 988 const char *ifsspc; 989 int had_param_ch = 0; 990 991 start = string; 992 993 if (ifslastp == NULL) { 994 /* Return entire argument, IFS doesn't apply to any of it */ 995 sp = (struct strlist *)stalloc(sizeof *sp); 996 sp->text = start; 997 *arglist->lastp = sp; 998 arglist->lastp = &sp->next; 999 return; 1000 } 1001 1002 ifs = ifsset() ? ifsval() : " \t\n"; 1003 1004 for (ifsp = &ifsfirst; ifsp != NULL; ifsp = ifsp->next) { 1005 p = string + ifsp->begoff; 1006 while (p < string + ifsp->endoff) { 1007 q = p; 1008 if (*p == CTLESC) 1009 p++; 1010 if (ifsp->inquotes) { 1011 /* Only NULs (should be from "$@") end args */ 1012 had_param_ch = 1; 1013 if (*p != 0) { 1014 p++; 1015 continue; 1016 } 1017 ifsspc = NULL; 1018 } else { 1019 if (!strchr(ifs, *p)) { 1020 had_param_ch = 1; 1021 p++; 1022 continue; 1023 } 1024 ifsspc = strchr(" \t\n", *p); 1025 1026 /* Ignore IFS whitespace at start */ 1027 if (q == start && ifsspc != NULL) { 1028 p++; 1029 start = p; 1030 continue; 1031 } 1032 had_param_ch = 0; 1033 } 1034 1035 /* Save this argument... */ 1036 *q = '\0'; 1037 sp = (struct strlist *)stalloc(sizeof *sp); 1038 sp->text = start; 1039 *arglist->lastp = sp; 1040 arglist->lastp = &sp->next; 1041 p++; 1042 1043 if (ifsspc != NULL) { 1044 /* Ignore further trailing IFS whitespace */ 1045 for (; p < string + ifsp->endoff; p++) { 1046 q = p; 1047 if (*p == CTLESC) 1048 p++; 1049 if (strchr(ifs, *p) == NULL) { 1050 p = q; 1051 break; 1052 } 1053 if (strchr(" \t\n", *p) == NULL) { 1054 p++; 1055 break; 1056 } 1057 } 1058 } 1059 start = p; 1060 } 1061 } 1062 1063 /* 1064 * Save anything left as an argument. 1065 * Traditionally we have treated 'IFS=':'; set -- x$IFS' as 1066 * generating 2 arguments, the second of which is empty. 1067 * Some recent clarification of the Posix spec say that it 1068 * should only generate one.... 1069 */ 1070 if (had_param_ch || *start != 0) { 1071 sp = (struct strlist *)stalloc(sizeof *sp); 1072 sp->text = start; 1073 *arglist->lastp = sp; 1074 arglist->lastp = &sp->next; 1075 } 1076 } 1077 1078 1079 1080 /* 1081 * Expand shell metacharacters. At this point, the only control characters 1082 * should be escapes. The results are stored in the list exparg. 1083 */ 1084 1085 STATIC char *expdir; 1086 1087 1088 STATIC void 1089 expandmeta(struct strlist *str, int flag __unused) 1090 { 1091 char *p; 1092 struct strlist **savelastp; 1093 struct strlist *sp; 1094 char c; 1095 /* TODO - EXP_REDIR */ 1096 1097 while (str) { 1098 if (fflag) 1099 goto nometa; 1100 p = str->text; 1101 for (;;) { /* fast check for meta chars */ 1102 if ((c = *p++) == '\0') 1103 goto nometa; 1104 if (c == '*' || c == '?' || c == '[' || c == '!') 1105 break; 1106 } 1107 savelastp = exparg.lastp; 1108 INTOFF; 1109 if (expdir == NULL) { 1110 int i = strlen(str->text); 1111 expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */ 1112 } 1113 1114 expmeta(expdir, str->text); 1115 ckfree(expdir); 1116 expdir = NULL; 1117 INTON; 1118 if (exparg.lastp == savelastp) { 1119 /* 1120 * no matches 1121 */ 1122 nometa: 1123 *exparg.lastp = str; 1124 rmescapes(str->text); 1125 exparg.lastp = &str->next; 1126 } else { 1127 *exparg.lastp = NULL; 1128 *savelastp = sp = expsort(*savelastp); 1129 while (sp->next != NULL) 1130 sp = sp->next; 1131 exparg.lastp = &sp->next; 1132 } 1133 str = str->next; 1134 } 1135 } 1136 1137 1138 /* 1139 * Do metacharacter (i.e. *, ?, [...]) expansion. 1140 */ 1141 1142 STATIC void 1143 expmeta(char *enddir, char *name) 1144 { 1145 char *p; 1146 char *q; 1147 char *start; 1148 char *endname; 1149 int metaflag; 1150 struct stat statb; 1151 DIR *dirp; 1152 struct dirent *dp; 1153 int atend; 1154 int matchdot; 1155 int esc; 1156 1157 metaflag = 0; 1158 start = name; 1159 for (p = name; esc = 0, *p; p += esc + 1) { 1160 if (*p == '*' || *p == '?') 1161 metaflag = 1; 1162 else if (*p == '[') { 1163 q = p + 1; 1164 if (*q == '!' || *q == '^') 1165 q++; 1166 for (;;) { 1167 while (*q == CTLQUOTEMARK) 1168 q++; 1169 if (*q == CTLESC) 1170 q++; 1171 if (*q == '/' || *q == '\0') 1172 break; 1173 if (*++q == ']') { 1174 metaflag = 1; 1175 break; 1176 } 1177 } 1178 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 1179 metaflag = 1; 1180 } else if (*p == '\0') 1181 break; 1182 else if (*p == CTLQUOTEMARK) 1183 continue; 1184 else { 1185 if (*p == CTLESC) 1186 esc++; 1187 if (p[esc] == '/') { 1188 if (metaflag) 1189 break; 1190 start = p + esc + 1; 1191 } 1192 } 1193 } 1194 if (metaflag == 0) { /* we've reached the end of the file name */ 1195 if (enddir != expdir) 1196 metaflag++; 1197 for (p = name ; ; p++) { 1198 if (*p == CTLQUOTEMARK) 1199 continue; 1200 if (*p == CTLESC) 1201 p++; 1202 *enddir++ = *p; 1203 if (*p == '\0') 1204 break; 1205 } 1206 if (metaflag == 0 || lstat(expdir, &statb) >= 0) 1207 addfname(expdir); 1208 return; 1209 } 1210 endname = p; 1211 if (start != name) { 1212 p = name; 1213 while (p < start) { 1214 while (*p == CTLQUOTEMARK) 1215 p++; 1216 if (*p == CTLESC) 1217 p++; 1218 *enddir++ = *p++; 1219 } 1220 } 1221 if (enddir == expdir) { 1222 p = "."; 1223 } else if (enddir == expdir + 1 && *expdir == '/') { 1224 p = "/"; 1225 } else { 1226 p = expdir; 1227 enddir[-1] = '\0'; 1228 } 1229 if ((dirp = opendir(p)) == NULL) 1230 return; 1231 if (enddir != expdir) 1232 enddir[-1] = '/'; 1233 if (*endname == 0) { 1234 atend = 1; 1235 } else { 1236 atend = 0; 1237 *endname = '\0'; 1238 endname += esc + 1; 1239 } 1240 matchdot = 0; 1241 p = start; 1242 while (*p == CTLQUOTEMARK) 1243 p++; 1244 if (*p == CTLESC) 1245 p++; 1246 if (*p == '.') 1247 matchdot++; 1248 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 1249 if (dp->d_name[0] == '.' && ! matchdot) 1250 continue; 1251 if (patmatch(start, dp->d_name, 0)) { 1252 if (atend) { 1253 scopy(dp->d_name, enddir); 1254 addfname(expdir); 1255 } else { 1256 for (p = enddir, q = dp->d_name; 1257 (*p++ = *q++) != '\0';) 1258 continue; 1259 p[-1] = '/'; 1260 expmeta(p, endname); 1261 } 1262 } 1263 } 1264 closedir(dirp); 1265 if (! atend) 1266 endname[-esc - 1] = esc ? CTLESC : '/'; 1267 } 1268 1269 1270 /* 1271 * Add a file name to the list. 1272 */ 1273 1274 STATIC void 1275 addfname(char *name) 1276 { 1277 char *p; 1278 struct strlist *sp; 1279 1280 p = stalloc(strlen(name) + 1); 1281 scopy(name, p); 1282 sp = (struct strlist *)stalloc(sizeof *sp); 1283 sp->text = p; 1284 *exparg.lastp = sp; 1285 exparg.lastp = &sp->next; 1286 } 1287 1288 1289 /* 1290 * Sort the results of file name expansion. It calculates the number of 1291 * strings to sort and then calls msort (short for merge sort) to do the 1292 * work. 1293 */ 1294 1295 STATIC struct strlist * 1296 expsort(struct strlist *str) 1297 { 1298 int len; 1299 struct strlist *sp; 1300 1301 len = 0; 1302 for (sp = str ; sp ; sp = sp->next) 1303 len++; 1304 return msort(str, len); 1305 } 1306 1307 1308 STATIC struct strlist * 1309 msort(struct strlist *list, int len) 1310 { 1311 struct strlist *p, *q = NULL; 1312 struct strlist **lpp; 1313 int half; 1314 int n; 1315 1316 if (len <= 1) 1317 return list; 1318 half = len >> 1; 1319 p = list; 1320 for (n = half ; --n >= 0 ; ) { 1321 q = p; 1322 p = p->next; 1323 } 1324 q->next = NULL; /* terminate first half of list */ 1325 q = msort(list, half); /* sort first half of list */ 1326 p = msort(p, len - half); /* sort second half */ 1327 lpp = &list; 1328 for (;;) { 1329 if (strcmp(p->text, q->text) < 0) { 1330 *lpp = p; 1331 lpp = &p->next; 1332 if ((p = *lpp) == NULL) { 1333 *lpp = q; 1334 break; 1335 } 1336 } else { 1337 *lpp = q; 1338 lpp = &q->next; 1339 if ((q = *lpp) == NULL) { 1340 *lpp = p; 1341 break; 1342 } 1343 } 1344 } 1345 return list; 1346 } 1347 1348 1349 1350 /* 1351 * Returns true if the pattern matches the string. 1352 */ 1353 1354 int 1355 patmatch(const char *pattern, const char *string, int squoted) 1356 { 1357 #ifdef notdef 1358 if (pattern[0] == '!' && pattern[1] == '!') 1359 return 1 - pmatch(pattern + 2, string); 1360 else 1361 #endif 1362 return pmatch(pattern, string, squoted); 1363 } 1364 1365 1366 STATIC int 1367 pmatch(const char *pattern, const char *string, int squoted) 1368 { 1369 const char *p, *q; 1370 char c; 1371 1372 p = pattern; 1373 q = string; 1374 for (;;) { 1375 switch (c = *p++) { 1376 case '\0': 1377 goto breakloop; 1378 case CTLESC: 1379 if (squoted && *q == CTLESC) 1380 q++; 1381 if (*q++ != *p++) 1382 return 0; 1383 break; 1384 case CTLQUOTEMARK: 1385 continue; 1386 case '?': 1387 if (squoted && *q == CTLESC) 1388 q++; 1389 if (*q++ == '\0') 1390 return 0; 1391 break; 1392 case '*': 1393 c = *p; 1394 while (c == CTLQUOTEMARK || c == '*') 1395 c = *++p; 1396 if (c != CTLESC && c != CTLQUOTEMARK && 1397 c != '?' && c != '*' && c != '[') { 1398 while (*q != c) { 1399 if (squoted && *q == CTLESC && 1400 q[1] == c) 1401 break; 1402 if (*q == '\0') 1403 return 0; 1404 if (squoted && *q == CTLESC) 1405 q++; 1406 q++; 1407 } 1408 } 1409 do { 1410 if (pmatch(p, q, squoted)) 1411 return 1; 1412 if (squoted && *q == CTLESC) 1413 q++; 1414 } while (*q++ != '\0'); 1415 return 0; 1416 case '[': { 1417 const char *endp; 1418 int invert, found; 1419 char chr; 1420 1421 endp = p; 1422 if (*endp == '!' || *endp == '^') 1423 endp++; 1424 for (;;) { 1425 while (*endp == CTLQUOTEMARK) 1426 endp++; 1427 if (*endp == '\0') 1428 goto dft; /* no matching ] */ 1429 if (*endp == CTLESC) 1430 endp++; 1431 if (*++endp == ']') 1432 break; 1433 } 1434 invert = 0; 1435 if (*p == '!' || *p == '^') { 1436 invert++; 1437 p++; 1438 } 1439 found = 0; 1440 chr = *q++; 1441 if (squoted && chr == CTLESC) 1442 chr = *q++; 1443 if (chr == '\0') 1444 return 0; 1445 c = *p++; 1446 do { 1447 if (c == CTLQUOTEMARK) 1448 continue; 1449 if (c == CTLESC) 1450 c = *p++; 1451 if (*p == '-' && p[1] != ']') { 1452 p++; 1453 while (*p == CTLQUOTEMARK) 1454 p++; 1455 if (*p == CTLESC) 1456 p++; 1457 if ( collate_range_cmp(chr, c) >= 0 1458 && collate_range_cmp(chr, *p) <= 0 1459 ) 1460 found = 1; 1461 p++; 1462 } else { 1463 if (chr == c) 1464 found = 1; 1465 } 1466 } while ((c = *p++) != ']'); 1467 if (found == invert) 1468 return 0; 1469 break; 1470 } 1471 dft: default: 1472 if (squoted && *q == CTLESC) 1473 q++; 1474 if (*q++ != c) 1475 return 0; 1476 break; 1477 } 1478 } 1479 breakloop: 1480 if (*q != '\0') 1481 return 0; 1482 return 1; 1483 } 1484 1485 1486 1487 /* 1488 * Remove any CTLESC characters from a string. 1489 */ 1490 1491 void 1492 rmescapes(char *str) 1493 { 1494 char *p, *q; 1495 1496 p = str; 1497 while (*p != CTLESC && *p != CTLQUOTEMARK) { 1498 if (*p++ == '\0') 1499 return; 1500 } 1501 q = p; 1502 while (*p) { 1503 if (*p == CTLQUOTEMARK) { 1504 p++; 1505 continue; 1506 } 1507 if (*p == CTLESC) 1508 p++; 1509 *q++ = *p++; 1510 } 1511 *q = '\0'; 1512 } 1513 1514 1515 1516 /* 1517 * See if a pattern matches in a case statement. 1518 */ 1519 1520 int 1521 casematch(union node *pattern, const char *val) 1522 { 1523 struct stackmark smark; 1524 int result; 1525 char *p; 1526 1527 setstackmark(&smark); 1528 argbackq = pattern->narg.backquote; 1529 STARTSTACKSTR(expdest); 1530 ifslastp = NULL; 1531 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); 1532 STPUTC('\0', expdest); 1533 p = grabstackstr(expdest); 1534 result = patmatch(p, val, 0); 1535 popstackmark(&smark); 1536 return result; 1537 } 1538 1539 /* 1540 * Our own itoa(). 1541 */ 1542 1543 STATIC char * 1544 cvtnum(int num, char *buf) 1545 { 1546 char temp[32]; 1547 int neg = num < 0; 1548 char *p = temp + 31; 1549 1550 temp[31] = '\0'; 1551 1552 do { 1553 *--p = num % 10 + '0'; 1554 } while ((num /= 10) != 0); 1555 1556 if (neg) 1557 *--p = '-'; 1558 1559 while (*p) 1560 STPUTC(*p++, buf); 1561 return buf; 1562 } 1563 1564 /* 1565 * Do most of the work for wordexp(3). 1566 */ 1567 1568 int 1569 wordexpcmd(int argc, char **argv) 1570 { 1571 size_t len; 1572 int i; 1573 1574 out1fmt("%08x", argc - 1); 1575 for (i = 1, len = 0; i < argc; i++) 1576 len += strlen(argv[i]); 1577 out1fmt("%08x", (int)len); 1578 for (i = 1; i < argc; i++) { 1579 out1str(argv[i]); 1580 out1c('\0'); 1581 } 1582 return (0); 1583 } 1584