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 37 #ifndef lint 38 static char sccsid[] = "@(#)expand.c 8.2 (Berkeley) 10/22/93"; 39 #endif /* not lint */ 40 41 /* 42 * Routines to expand arguments to commands. We have to deal with 43 * backquotes, shell variables, and file metacharacters. 44 */ 45 46 #include "shell.h" 47 #include "main.h" 48 #include "nodes.h" 49 #include "eval.h" 50 #include "expand.h" 51 #include "syntax.h" 52 #include "parser.h" 53 #include "jobs.h" 54 #include "options.h" 55 #include "var.h" 56 #include "input.h" 57 #include "output.h" 58 #include "memalloc.h" 59 #include "error.h" 60 #include "mystring.h" 61 #include <sys/types.h> 62 #include <sys/time.h> 63 #include <sys/stat.h> 64 #include <errno.h> 65 #include <dirent.h> 66 #include <unistd.h> 67 #include <pwd.h> 68 69 /* 70 * Structure specifying which parts of the string should be searched 71 * for IFS characters. 72 */ 73 74 struct ifsregion { 75 struct ifsregion *next; /* next region in list */ 76 int begoff; /* offset of start of region */ 77 int endoff; /* offset of end of region */ 78 int nulonly; /* search for nul bytes only */ 79 }; 80 81 82 char *expdest; /* output of current string */ 83 struct nodelist *argbackq; /* list of back quote expressions */ 84 struct ifsregion ifsfirst; /* first struct in list of ifs regions */ 85 struct ifsregion *ifslastp; /* last struct in list */ 86 struct arglist exparg; /* holds expanded arg list */ 87 88 #ifdef __STDC__ 89 STATIC void argstr(char *, int); 90 STATIC void expbackq(union node *, int, int); 91 STATIC char *evalvar(char *, int); 92 STATIC int varisset(int); 93 STATIC void varvalue(int, int, int); 94 STATIC void recordregion(int, int, int); 95 STATIC void ifsbreakup(char *, struct arglist *); 96 STATIC void expandmeta(struct strlist *, int); 97 STATIC void expmeta(char *, char *); 98 STATIC void expari(int); 99 STATIC void addfname(char *); 100 STATIC struct strlist *expsort(struct strlist *); 101 STATIC struct strlist *msort(struct strlist *, int); 102 STATIC int pmatch(char *, char *); 103 STATIC char *exptilde(char *, int); 104 #else 105 STATIC void argstr(); 106 STATIC void expbackq(); 107 STATIC char *evalvar(); 108 STATIC int varisset(); 109 STATIC void varvalue(); 110 STATIC void recordregion(); 111 STATIC void ifsbreakup(); 112 STATIC void expandmeta(); 113 STATIC void expmeta(); 114 STATIC void expari(); 115 STATIC void addfname(); 116 STATIC struct strlist *expsort(); 117 STATIC struct strlist *msort(); 118 STATIC int pmatch(); 119 STATIC char *exptilde(); 120 #endif 121 122 /* 123 * Expand shell variables and backquotes inside a here document. 124 */ 125 126 void 127 expandhere(arg, fd) 128 union node *arg; /* the document */ 129 int fd; /* where to write the expanded version */ 130 { 131 herefd = fd; 132 expandarg(arg, (struct arglist *)NULL, 0); 133 xwrite(fd, stackblock(), expdest - stackblock()); 134 } 135 136 137 /* 138 * Perform variable substitution and command substitution on an argument, 139 * placing the resulting list of arguments in arglist. If EXP_FULL is true, 140 * perform splitting and file name expansion. When arglist is NULL, perform 141 * here document expansion. 142 */ 143 144 void 145 expandarg(arg, arglist, flag) 146 union node *arg; 147 struct arglist *arglist; 148 { 149 struct strlist *sp; 150 char *p; 151 152 argbackq = arg->narg.backquote; 153 STARTSTACKSTR(expdest); 154 ifsfirst.next = NULL; 155 ifslastp = NULL; 156 argstr(arg->narg.text, flag); 157 if (arglist == NULL) { 158 return; /* here document expanded */ 159 } 160 STPUTC('\0', expdest); 161 p = grabstackstr(expdest); 162 exparg.lastp = &exparg.list; 163 /* 164 * TODO - EXP_REDIR 165 */ 166 if (flag & EXP_FULL) { 167 ifsbreakup(p, &exparg); 168 *exparg.lastp = NULL; 169 exparg.lastp = &exparg.list; 170 expandmeta(exparg.list, flag); 171 } else { 172 if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */ 173 rmescapes(p); 174 sp = (struct strlist *)stalloc(sizeof (struct strlist)); 175 sp->text = p; 176 *exparg.lastp = sp; 177 exparg.lastp = &sp->next; 178 } 179 while (ifsfirst.next != NULL) { 180 struct ifsregion *ifsp; 181 INTOFF; 182 ifsp = ifsfirst.next->next; 183 ckfree(ifsfirst.next); 184 ifsfirst.next = ifsp; 185 INTON; 186 } 187 *exparg.lastp = NULL; 188 if (exparg.list) { 189 *arglist->lastp = exparg.list; 190 arglist->lastp = exparg.lastp; 191 } 192 } 193 194 195 196 /* 197 * Perform variable and command substitution. If EXP_FULL is set, output CTLESC 198 * characters to allow for further processing. Otherwise treat 199 * $@ like $* since no splitting will be performed. 200 */ 201 202 STATIC void 203 argstr(p, flag) 204 register char *p; 205 { 206 register char c; 207 int quotes = flag & (EXP_FULL | EXP_CASE); /* do CTLESC */ 208 int firsteq = 1; 209 210 if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE))) 211 p = exptilde(p, flag); 212 for (;;) { 213 switch (c = *p++) { 214 case '\0': 215 case CTLENDVAR: /* ??? */ 216 goto breakloop; 217 case CTLESC: 218 if (quotes) 219 STPUTC(c, expdest); 220 c = *p++; 221 STPUTC(c, expdest); 222 break; 223 case CTLVAR: 224 p = evalvar(p, flag); 225 break; 226 case CTLBACKQ: 227 case CTLBACKQ|CTLQUOTE: 228 expbackq(argbackq->n, c & CTLQUOTE, flag); 229 argbackq = argbackq->next; 230 break; 231 case CTLENDARI: 232 expari(flag); 233 break; 234 case ':': 235 case '=': 236 /* 237 * sort of a hack - expand tildes in variable 238 * assignments (after the first '=' and after ':'s). 239 */ 240 STPUTC(c, expdest); 241 if (flag & EXP_VARTILDE && *p == '~') { 242 if (c == '=') { 243 if (firsteq) 244 firsteq = 0; 245 else 246 break; 247 } 248 p = exptilde(p, flag); 249 } 250 break; 251 default: 252 STPUTC(c, expdest); 253 } 254 } 255 breakloop:; 256 } 257 258 STATIC char * 259 exptilde(p, flag) 260 char *p; 261 { 262 char c, *startp = p; 263 struct passwd *pw; 264 char *home; 265 int quotes = flag & (EXP_FULL | EXP_CASE); 266 267 while (c = *p) { 268 switch(c) { 269 case CTLESC: 270 return (startp); 271 case ':': 272 if (flag & EXP_VARTILDE) 273 goto done; 274 break; 275 case '/': 276 goto done; 277 } 278 p++; 279 } 280 done: 281 *p = '\0'; 282 if (*(startp+1) == '\0') { 283 if ((home = lookupvar("HOME")) == NULL) 284 goto lose; 285 } else { 286 if ((pw = getpwnam(startp+1)) == NULL) 287 goto lose; 288 home = pw->pw_dir; 289 } 290 if (*home == '\0') 291 goto lose; 292 *p = c; 293 while (c = *home++) { 294 if (quotes && SQSYNTAX[c] == CCTL) 295 STPUTC(CTLESC, expdest); 296 STPUTC(c, expdest); 297 } 298 return (p); 299 lose: 300 *p = c; 301 return (startp); 302 } 303 304 305 /* 306 * Expand arithmetic expression. Backup to start of expression, 307 * evaluate, place result in (backed up) result, adjust string position. 308 */ 309 void 310 expari(flag) 311 { 312 char *p, *start; 313 int result; 314 int quotes = flag & (EXP_FULL | EXP_CASE); 315 316 /* 317 * This routine is slightly over-compilcated for 318 * efficiency. First we make sure there is 319 * enough space for the result, which may be bigger 320 * than the expression if we add exponentation. Next we 321 * scan backwards looking for the start of arithmetic. If the 322 * next previous character is a CTLESC character, then we 323 * have to rescan starting from the beginning since CTLESC 324 * characters have to be processed left to right. 325 */ 326 CHECKSTRSPACE(8, expdest); 327 USTPUTC('\0', expdest); 328 start = stackblock(); 329 p = expdest; 330 while (*p != CTLARI && p >= start) 331 --p; 332 if (*p != CTLARI) 333 error("missing CTLARI (shouldn't happen)"); 334 if (p > start && *(p-1) == CTLESC) 335 for (p = start; *p != CTLARI; p++) 336 if (*p == CTLESC) 337 p++; 338 if (quotes) 339 rmescapes(p+1); 340 result = arith(p+1); 341 fmtstr(p, 10, "%d", result); 342 while (*p++) 343 ; 344 result = expdest - p + 1; 345 STADJUST(-result, expdest); 346 } 347 348 349 /* 350 * Expand stuff in backwards quotes. 351 */ 352 353 STATIC void 354 expbackq(cmd, quoted, flag) 355 union node *cmd; 356 { 357 struct backcmd in; 358 int i; 359 char buf[128]; 360 char *p; 361 char *dest = expdest; 362 struct ifsregion saveifs, *savelastp; 363 struct nodelist *saveargbackq; 364 char lastc; 365 int startloc = dest - stackblock(); 366 char const *syntax = quoted? DQSYNTAX : BASESYNTAX; 367 int saveherefd; 368 int quotes = flag & (EXP_FULL | EXP_CASE); 369 370 INTOFF; 371 saveifs = ifsfirst; 372 savelastp = ifslastp; 373 saveargbackq = argbackq; 374 saveherefd = herefd; 375 herefd = -1; 376 p = grabstackstr(dest); 377 evalbackcmd(cmd, &in); 378 ungrabstackstr(p, dest); 379 ifsfirst = saveifs; 380 ifslastp = savelastp; 381 argbackq = saveargbackq; 382 herefd = saveherefd; 383 384 p = in.buf; 385 lastc = '\0'; 386 for (;;) { 387 if (--in.nleft < 0) { 388 if (in.fd < 0) 389 break; 390 while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR); 391 TRACE(("expbackq: read returns %d\n", i)); 392 if (i <= 0) 393 break; 394 p = buf; 395 in.nleft = i - 1; 396 } 397 lastc = *p++; 398 if (lastc != '\0') { 399 if (quotes && syntax[lastc] == CCTL) 400 STPUTC(CTLESC, dest); 401 STPUTC(lastc, dest); 402 } 403 } 404 if (lastc == '\n') { 405 STUNPUTC(dest); 406 } 407 if (in.fd >= 0) 408 close(in.fd); 409 if (in.buf) 410 ckfree(in.buf); 411 if (in.jp) 412 exitstatus = waitforjob(in.jp); 413 if (quoted == 0) 414 recordregion(startloc, dest - stackblock(), 0); 415 TRACE(("evalbackq: size=%d: \"%.*s\"\n", 416 (dest - stackblock()) - startloc, 417 (dest - stackblock()) - startloc, 418 stackblock() + startloc)); 419 expdest = dest; 420 INTON; 421 } 422 423 424 425 /* 426 * Expand a variable, and return a pointer to the next character in the 427 * input string. 428 */ 429 430 STATIC char * 431 evalvar(p, flag) 432 char *p; 433 { 434 int subtype; 435 int varflags; 436 char *var; 437 char *val; 438 int c; 439 int set; 440 int special; 441 int startloc; 442 int quotes = flag & (EXP_FULL | EXP_CASE); 443 444 varflags = *p++; 445 subtype = varflags & VSTYPE; 446 var = p; 447 special = 0; 448 if (! is_name(*p)) 449 special = 1; 450 p = strchr(p, '=') + 1; 451 again: /* jump here after setting a variable with ${var=text} */ 452 if (special) { 453 set = varisset(*var); 454 val = NULL; 455 } else { 456 val = lookupvar(var); 457 if (val == NULL || (varflags & VSNUL) && val[0] == '\0') { 458 val = NULL; 459 set = 0; 460 } else 461 set = 1; 462 } 463 startloc = expdest - stackblock(); 464 if (set && subtype != VSPLUS) { 465 /* insert the value of the variable */ 466 if (special) { 467 varvalue(*var, varflags & VSQUOTE, flag & EXP_FULL); 468 } else { 469 char const *syntax = (varflags & VSQUOTE)? DQSYNTAX : BASESYNTAX; 470 471 while (*val) { 472 if (quotes && syntax[*val] == CCTL) 473 STPUTC(CTLESC, expdest); 474 STPUTC(*val++, expdest); 475 } 476 } 477 } 478 if (subtype == VSPLUS) 479 set = ! set; 480 if (((varflags & VSQUOTE) == 0 || (*var == '@' && shellparam.nparam != 1)) 481 && (set || subtype == VSNORMAL)) 482 recordregion(startloc, expdest - stackblock(), varflags & VSQUOTE); 483 if (! set && subtype != VSNORMAL) { 484 if (subtype == VSPLUS || subtype == VSMINUS) { 485 argstr(p, flag); 486 } else { 487 char *startp; 488 int saveherefd = herefd; 489 struct nodelist *saveargbackq = argbackq; 490 herefd = -1; 491 argstr(p, 0); 492 STACKSTRNUL(expdest); 493 herefd = saveherefd; 494 argbackq = saveargbackq; 495 startp = stackblock() + startloc; 496 if (subtype == VSASSIGN) { 497 setvar(var, startp, 0); 498 STADJUST(startp - expdest, expdest); 499 varflags &=~ VSNUL; 500 goto again; 501 } 502 /* subtype == VSQUESTION */ 503 if (*p != CTLENDVAR) { 504 outfmt(&errout, "%s\n", startp); 505 error((char *)NULL); 506 } 507 error("%.*s: parameter %snot set", p - var - 1, 508 var, (varflags & VSNUL)? "null or " : nullstr); 509 } 510 } 511 if (subtype != VSNORMAL) { /* skip to end of alternative */ 512 int nesting = 1; 513 for (;;) { 514 if ((c = *p++) == CTLESC) 515 p++; 516 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { 517 if (set) 518 argbackq = argbackq->next; 519 } else if (c == CTLVAR) { 520 if ((*p++ & VSTYPE) != VSNORMAL) 521 nesting++; 522 } else if (c == CTLENDVAR) { 523 if (--nesting == 0) 524 break; 525 } 526 } 527 } 528 return p; 529 } 530 531 532 533 /* 534 * Test whether a specialized variable is set. 535 */ 536 537 STATIC int 538 varisset(name) 539 char name; 540 { 541 char **ap; 542 543 if (name == '!') { 544 if (backgndpid == -1) 545 return 0; 546 } else if (name == '@' || name == '*') { 547 if (*shellparam.p == NULL) 548 return 0; 549 } else if ((unsigned)(name -= '1') <= '9' - '1') { 550 ap = shellparam.p; 551 do { 552 if (*ap++ == NULL) 553 return 0; 554 } while (--name >= 0); 555 } 556 return 1; 557 } 558 559 560 561 /* 562 * Add the value of a specialized variable to the stack string. 563 */ 564 565 STATIC void 566 varvalue(name, quoted, allow_split) 567 char name; 568 { 569 int num; 570 char temp[32]; 571 char *p; 572 int i; 573 extern int exitstatus; 574 char sep; 575 char **ap; 576 char const *syntax; 577 578 #define STRTODEST(p) \ 579 do {\ 580 if (allow_split) { \ 581 syntax = quoted? DQSYNTAX : BASESYNTAX; \ 582 while (*p) { \ 583 if (syntax[*p] == CCTL) \ 584 STPUTC(CTLESC, expdest); \ 585 STPUTC(*p++, expdest); \ 586 } \ 587 } else \ 588 while (*p) \ 589 STPUTC(*p++, expdest); \ 590 } while (0) 591 592 593 switch (name) { 594 case '$': 595 num = rootpid; 596 goto numvar; 597 case '?': 598 num = exitstatus; 599 goto numvar; 600 case '#': 601 num = shellparam.nparam; 602 goto numvar; 603 case '!': 604 num = backgndpid; 605 numvar: 606 p = temp + 31; 607 temp[31] = '\0'; 608 do { 609 *--p = num % 10 + '0'; 610 } while ((num /= 10) != 0); 611 while (*p) 612 STPUTC(*p++, expdest); 613 break; 614 case '-': 615 for (i = 0 ; i < NOPTS ; i++) { 616 if (optlist[i].val) 617 STPUTC(optlist[i].letter, expdest); 618 } 619 break; 620 case '@': 621 if (allow_split) { 622 sep = '\0'; 623 goto allargs; 624 } 625 /* fall through */ 626 case '*': 627 sep = ' '; 628 allargs: 629 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 630 STRTODEST(p); 631 if (*ap) 632 STPUTC(sep, expdest); 633 } 634 break; 635 case '0': 636 p = arg0; 637 STRTODEST(p); 638 break; 639 default: 640 if ((unsigned)(name -= '1') <= '9' - '1') { 641 p = shellparam.p[name]; 642 STRTODEST(p); 643 } 644 break; 645 } 646 } 647 648 649 650 /* 651 * Record the the fact that we have to scan this region of the 652 * string for IFS characters. 653 */ 654 655 STATIC void 656 recordregion(start, end, nulonly) { 657 register struct ifsregion *ifsp; 658 659 if (ifslastp == NULL) { 660 ifsp = &ifsfirst; 661 } else { 662 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 663 ifslastp->next = ifsp; 664 } 665 ifslastp = ifsp; 666 ifslastp->next = NULL; 667 ifslastp->begoff = start; 668 ifslastp->endoff = end; 669 ifslastp->nulonly = nulonly; 670 } 671 672 673 674 /* 675 * Break the argument string into pieces based upon IFS and add the 676 * strings to the argument list. The regions of the string to be 677 * searched for IFS characters have been stored by recordregion. 678 */ 679 680 STATIC void 681 ifsbreakup(string, arglist) 682 char *string; 683 struct arglist *arglist; 684 { 685 struct ifsregion *ifsp; 686 struct strlist *sp; 687 char *start; 688 register char *p; 689 char *q; 690 char *ifs; 691 692 start = string; 693 if (ifslastp != NULL) { 694 ifsp = &ifsfirst; 695 do { 696 p = string + ifsp->begoff; 697 ifs = ifsp->nulonly? nullstr : ifsval(); 698 while (p < string + ifsp->endoff) { 699 q = p; 700 if (*p == CTLESC) 701 p++; 702 if (strchr(ifs, *p++)) { 703 if (q > start || *ifs != ' ') { 704 *q = '\0'; 705 sp = (struct strlist *)stalloc(sizeof *sp); 706 sp->text = start; 707 *arglist->lastp = sp; 708 arglist->lastp = &sp->next; 709 } 710 if (*ifs == ' ') { 711 for (;;) { 712 if (p >= string + ifsp->endoff) 713 break; 714 q = p; 715 if (*p == CTLESC) 716 p++; 717 if (strchr(ifs, *p++) == NULL) { 718 p = q; 719 break; 720 } 721 } 722 } 723 start = p; 724 } 725 } 726 } while ((ifsp = ifsp->next) != NULL); 727 if (*start || (*ifs != ' ' && start > string)) { 728 sp = (struct strlist *)stalloc(sizeof *sp); 729 sp->text = start; 730 *arglist->lastp = sp; 731 arglist->lastp = &sp->next; 732 } 733 } else { 734 sp = (struct strlist *)stalloc(sizeof *sp); 735 sp->text = start; 736 *arglist->lastp = sp; 737 arglist->lastp = &sp->next; 738 } 739 } 740 741 742 743 /* 744 * Expand shell metacharacters. At this point, the only control characters 745 * should be escapes. The results are stored in the list exparg. 746 */ 747 748 char *expdir; 749 750 751 STATIC void 752 expandmeta(str, flag) 753 struct strlist *str; 754 { 755 char *p; 756 struct strlist **savelastp; 757 struct strlist *sp; 758 char c; 759 /* TODO - EXP_REDIR */ 760 761 while (str) { 762 if (fflag) 763 goto nometa; 764 p = str->text; 765 for (;;) { /* fast check for meta chars */ 766 if ((c = *p++) == '\0') 767 goto nometa; 768 if (c == '*' || c == '?' || c == '[' || c == '!') 769 break; 770 } 771 savelastp = exparg.lastp; 772 INTOFF; 773 if (expdir == NULL) { 774 int i = strlen(str->text); 775 expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */ 776 } 777 778 expmeta(expdir, str->text); 779 ckfree(expdir); 780 expdir = NULL; 781 INTON; 782 if (exparg.lastp == savelastp) { 783 /* 784 * no matches 785 */ 786 nometa: 787 *exparg.lastp = str; 788 rmescapes(str->text); 789 exparg.lastp = &str->next; 790 } else { 791 *exparg.lastp = NULL; 792 *savelastp = sp = expsort(*savelastp); 793 while (sp->next != NULL) 794 sp = sp->next; 795 exparg.lastp = &sp->next; 796 } 797 str = str->next; 798 } 799 } 800 801 802 /* 803 * Do metacharacter (i.e. *, ?, [...]) expansion. 804 */ 805 806 STATIC void 807 expmeta(enddir, name) 808 char *enddir; 809 char *name; 810 { 811 register char *p; 812 char *q; 813 char *start; 814 char *endname; 815 int metaflag; 816 struct stat statb; 817 DIR *dirp; 818 struct dirent *dp; 819 int atend; 820 int matchdot; 821 822 metaflag = 0; 823 start = name; 824 for (p = name ; ; p++) { 825 if (*p == '*' || *p == '?') 826 metaflag = 1; 827 else if (*p == '[') { 828 q = p + 1; 829 if (*q == '!') 830 q++; 831 for (;;) { 832 if (*q == CTLESC) 833 q++; 834 if (*q == '/' || *q == '\0') 835 break; 836 if (*++q == ']') { 837 metaflag = 1; 838 break; 839 } 840 } 841 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 842 metaflag = 1; 843 } else if (*p == '\0') 844 break; 845 else if (*p == CTLESC) 846 p++; 847 if (*p == '/') { 848 if (metaflag) 849 break; 850 start = p + 1; 851 } 852 } 853 if (metaflag == 0) { /* we've reached the end of the file name */ 854 if (enddir != expdir) 855 metaflag++; 856 for (p = name ; ; p++) { 857 if (*p == CTLESC) 858 p++; 859 *enddir++ = *p; 860 if (*p == '\0') 861 break; 862 } 863 if (metaflag == 0 || stat(expdir, &statb) >= 0) 864 addfname(expdir); 865 return; 866 } 867 endname = p; 868 if (start != name) { 869 p = name; 870 while (p < start) { 871 if (*p == CTLESC) 872 p++; 873 *enddir++ = *p++; 874 } 875 } 876 if (enddir == expdir) { 877 p = "."; 878 } else if (enddir == expdir + 1 && *expdir == '/') { 879 p = "/"; 880 } else { 881 p = expdir; 882 enddir[-1] = '\0'; 883 } 884 if ((dirp = opendir(p)) == NULL) 885 return; 886 if (enddir != expdir) 887 enddir[-1] = '/'; 888 if (*endname == 0) { 889 atend = 1; 890 } else { 891 atend = 0; 892 *endname++ = '\0'; 893 } 894 matchdot = 0; 895 if (start[0] == '.' || start[0] == CTLESC && start[1] == '.') 896 matchdot++; 897 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 898 if (dp->d_name[0] == '.' && ! matchdot) 899 continue; 900 if (patmatch(start, dp->d_name)) { 901 if (atend) { 902 scopy(dp->d_name, enddir); 903 addfname(expdir); 904 } else { 905 char *q; 906 for (p = enddir, q = dp->d_name ; *p++ = *q++ ;); 907 p[-1] = '/'; 908 expmeta(p, endname); 909 } 910 } 911 } 912 closedir(dirp); 913 if (! atend) 914 endname[-1] = '/'; 915 } 916 917 918 /* 919 * Add a file name to the list. 920 */ 921 922 STATIC void 923 addfname(name) 924 char *name; 925 { 926 char *p; 927 struct strlist *sp; 928 929 p = stalloc(strlen(name) + 1); 930 scopy(name, p); 931 sp = (struct strlist *)stalloc(sizeof *sp); 932 sp->text = p; 933 *exparg.lastp = sp; 934 exparg.lastp = &sp->next; 935 } 936 937 938 /* 939 * Sort the results of file name expansion. It calculates the number of 940 * strings to sort and then calls msort (short for merge sort) to do the 941 * work. 942 */ 943 944 STATIC struct strlist * 945 expsort(str) 946 struct strlist *str; 947 { 948 int len; 949 struct strlist *sp; 950 951 len = 0; 952 for (sp = str ; sp ; sp = sp->next) 953 len++; 954 return msort(str, len); 955 } 956 957 958 STATIC struct strlist * 959 msort(list, len) 960 struct strlist *list; 961 { 962 struct strlist *p, *q; 963 struct strlist **lpp; 964 int half; 965 int n; 966 967 if (len <= 1) 968 return list; 969 half = len >> 1; 970 p = list; 971 for (n = half ; --n >= 0 ; ) { 972 q = p; 973 p = p->next; 974 } 975 q->next = NULL; /* terminate first half of list */ 976 q = msort(list, half); /* sort first half of list */ 977 p = msort(p, len - half); /* sort second half */ 978 lpp = &list; 979 for (;;) { 980 if (strcmp(p->text, q->text) < 0) { 981 *lpp = p; 982 lpp = &p->next; 983 if ((p = *lpp) == NULL) { 984 *lpp = q; 985 break; 986 } 987 } else { 988 *lpp = q; 989 lpp = &q->next; 990 if ((q = *lpp) == NULL) { 991 *lpp = p; 992 break; 993 } 994 } 995 } 996 return list; 997 } 998 999 1000 1001 /* 1002 * Returns true if the pattern matches the string. 1003 */ 1004 1005 int 1006 patmatch(pattern, string) 1007 char *pattern; 1008 char *string; 1009 { 1010 #ifdef notdef 1011 if (pattern[0] == '!' && pattern[1] == '!') 1012 return 1 - pmatch(pattern + 2, string); 1013 else 1014 #endif 1015 return pmatch(pattern, string); 1016 } 1017 1018 1019 STATIC int 1020 pmatch(pattern, string) 1021 char *pattern; 1022 char *string; 1023 { 1024 register char *p, *q; 1025 register char c; 1026 1027 p = pattern; 1028 q = string; 1029 for (;;) { 1030 switch (c = *p++) { 1031 case '\0': 1032 goto breakloop; 1033 case CTLESC: 1034 if (*q++ != *p++) 1035 return 0; 1036 break; 1037 case '?': 1038 if (*q++ == '\0') 1039 return 0; 1040 break; 1041 case '*': 1042 c = *p; 1043 if (c != CTLESC && c != '?' && c != '*' && c != '[') { 1044 while (*q != c) { 1045 if (*q == '\0') 1046 return 0; 1047 q++; 1048 } 1049 } 1050 do { 1051 if (pmatch(p, q)) 1052 return 1; 1053 } while (*q++ != '\0'); 1054 return 0; 1055 case '[': { 1056 char *endp; 1057 int invert, found; 1058 char chr; 1059 1060 endp = p; 1061 if (*endp == '!') 1062 endp++; 1063 for (;;) { 1064 if (*endp == '\0') 1065 goto dft; /* no matching ] */ 1066 if (*endp == CTLESC) 1067 endp++; 1068 if (*++endp == ']') 1069 break; 1070 } 1071 invert = 0; 1072 if (*p == '!') { 1073 invert++; 1074 p++; 1075 } 1076 found = 0; 1077 chr = *q++; 1078 c = *p++; 1079 do { 1080 if (c == CTLESC) 1081 c = *p++; 1082 if (*p == '-' && p[1] != ']') { 1083 p++; 1084 if (*p == CTLESC) 1085 p++; 1086 if (chr >= c && chr <= *p) 1087 found = 1; 1088 p++; 1089 } else { 1090 if (chr == c) 1091 found = 1; 1092 } 1093 } while ((c = *p++) != ']'); 1094 if (found == invert) 1095 return 0; 1096 break; 1097 } 1098 dft: default: 1099 if (*q++ != c) 1100 return 0; 1101 break; 1102 } 1103 } 1104 breakloop: 1105 if (*q != '\0') 1106 return 0; 1107 return 1; 1108 } 1109 1110 1111 1112 /* 1113 * Remove any CTLESC characters from a string. 1114 */ 1115 1116 void 1117 rmescapes(str) 1118 char *str; 1119 { 1120 register char *p, *q; 1121 1122 p = str; 1123 while (*p != CTLESC) { 1124 if (*p++ == '\0') 1125 return; 1126 } 1127 q = p; 1128 while (*p) { 1129 if (*p == CTLESC) 1130 p++; 1131 *q++ = *p++; 1132 } 1133 *q = '\0'; 1134 } 1135 1136 1137 1138 /* 1139 * See if a pattern matches in a case statement. 1140 */ 1141 1142 int 1143 casematch(pattern, val) 1144 union node *pattern; 1145 char *val; 1146 { 1147 struct stackmark smark; 1148 int result; 1149 char *p; 1150 1151 setstackmark(&smark); 1152 argbackq = pattern->narg.backquote; 1153 STARTSTACKSTR(expdest); 1154 ifslastp = NULL; 1155 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); 1156 STPUTC('\0', expdest); 1157 p = grabstackstr(expdest); 1158 result = patmatch(p, val); 1159 popstackmark(&smark); 1160 return result; 1161 } 1162