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 * $Id: expand.c,v 1.3 1995/03/01 13:04:15 guido Exp $ 37 */ 38 39 #ifndef lint 40 static char sccsid[] = "@(#)expand.c 8.2 (Berkeley) 10/22/93"; 41 #endif /* not lint */ 42 43 /* 44 * Routines to expand arguments to commands. We have to deal with 45 * backquotes, shell variables, and file metacharacters. 46 */ 47 48 #include "shell.h" 49 #include "main.h" 50 #include "nodes.h" 51 #include "eval.h" 52 #include "expand.h" 53 #include "syntax.h" 54 #include "parser.h" 55 #include "jobs.h" 56 #include "options.h" 57 #include "var.h" 58 #include "input.h" 59 #include "output.h" 60 #include "memalloc.h" 61 #include "error.h" 62 #include "mystring.h" 63 #include <sys/types.h> 64 #include <sys/time.h> 65 #include <sys/stat.h> 66 #include <errno.h> 67 #include <dirent.h> 68 #include <pwd.h> 69 70 /* 71 * Structure specifying which parts of the string should be searched 72 * for IFS characters. 73 */ 74 75 struct ifsregion { 76 struct ifsregion *next; /* next region in list */ 77 int begoff; /* offset of start of region */ 78 int endoff; /* offset of end of region */ 79 int nulonly; /* search for nul bytes only */ 80 }; 81 82 83 char *expdest; /* output of current string */ 84 struct nodelist *argbackq; /* list of back quote expressions */ 85 struct ifsregion ifsfirst; /* first struct in list of ifs regions */ 86 struct ifsregion *ifslastp; /* last struct in list */ 87 struct arglist exparg; /* holds expanded arg list */ 88 89 #ifdef __STDC__ 90 STATIC void argstr(char *, int); 91 STATIC void expbackq(union node *, int, int); 92 STATIC char *evalvar(char *, int); 93 STATIC int varisset(int); 94 STATIC void varvalue(int, int, int); 95 STATIC void recordregion(int, int, int); 96 STATIC void ifsbreakup(char *, struct arglist *); 97 STATIC void expandmeta(struct strlist *, int); 98 STATIC void expmeta(char *, char *); 99 STATIC void expari(int); 100 STATIC void addfname(char *); 101 STATIC struct strlist *expsort(struct strlist *); 102 STATIC struct strlist *msort(struct strlist *, int); 103 STATIC int pmatch(char *, char *); 104 STATIC char *exptilde(char *, int); 105 #else 106 STATIC void argstr(); 107 STATIC void expbackq(); 108 STATIC char *evalvar(); 109 STATIC int varisset(); 110 STATIC void varvalue(); 111 STATIC void recordregion(); 112 STATIC void ifsbreakup(); 113 STATIC void expandmeta(); 114 STATIC void expmeta(); 115 STATIC void expari(); 116 STATIC void addfname(); 117 STATIC struct strlist *expsort(); 118 STATIC struct strlist *msort(); 119 STATIC int pmatch(); 120 STATIC char *exptilde(); 121 #endif 122 123 /* 124 * Expand shell variables and backquotes inside a here document. 125 */ 126 127 void 128 expandhere(arg, fd) 129 union node *arg; /* the document */ 130 int fd; /* where to write the expanded version */ 131 { 132 herefd = fd; 133 expandarg(arg, (struct arglist *)NULL, 0); 134 xwrite(fd, stackblock(), expdest - stackblock()); 135 } 136 137 138 /* 139 * Perform variable substitution and command substitution on an argument, 140 * placing the resulting list of arguments in arglist. If EXP_FULL is true, 141 * perform splitting and file name expansion. When arglist is NULL, perform 142 * here document expansion. 143 */ 144 145 void 146 expandarg(arg, arglist, flag) 147 union node *arg; 148 struct arglist *arglist; 149 { 150 struct strlist *sp; 151 char *p; 152 153 argbackq = arg->narg.backquote; 154 STARTSTACKSTR(expdest); 155 ifsfirst.next = NULL; 156 ifslastp = NULL; 157 argstr(arg->narg.text, flag); 158 if (arglist == NULL) { 159 return; /* here document expanded */ 160 } 161 STPUTC('\0', expdest); 162 p = grabstackstr(expdest); 163 exparg.lastp = &exparg.list; 164 /* 165 * TODO - EXP_REDIR 166 */ 167 if (flag & EXP_FULL) { 168 ifsbreakup(p, &exparg); 169 *exparg.lastp = NULL; 170 exparg.lastp = &exparg.list; 171 expandmeta(exparg.list, flag); 172 } else { 173 if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */ 174 rmescapes(p); 175 sp = (struct strlist *)stalloc(sizeof (struct strlist)); 176 sp->text = p; 177 *exparg.lastp = sp; 178 exparg.lastp = &sp->next; 179 } 180 while (ifsfirst.next != NULL) { 181 struct ifsregion *ifsp; 182 INTOFF; 183 ifsp = ifsfirst.next->next; 184 ckfree(ifsfirst.next); 185 ifsfirst.next = ifsp; 186 INTON; 187 } 188 *exparg.lastp = NULL; 189 if (exparg.list) { 190 *arglist->lastp = exparg.list; 191 arglist->lastp = exparg.lastp; 192 } 193 } 194 195 196 197 /* 198 * Perform variable and command substitution. If EXP_FULL is set, output CTLESC 199 * characters to allow for further processing. Otherwise treat 200 * $@ like $* since no splitting will be performed. 201 */ 202 203 STATIC void 204 argstr(p, flag) 205 register char *p; 206 { 207 register char c; 208 int quotes = flag & (EXP_FULL | EXP_CASE); /* 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 CTLESC: 219 if (quotes) 220 STPUTC(c, expdest); 221 c = *p++; 222 STPUTC(c, expdest); 223 break; 224 case CTLVAR: 225 p = evalvar(p, flag); 226 break; 227 case CTLBACKQ: 228 case CTLBACKQ|CTLQUOTE: 229 expbackq(argbackq->n, c & CTLQUOTE, flag); 230 argbackq = argbackq->next; 231 break; 232 case CTLENDARI: 233 expari(flag); 234 break; 235 case ':': 236 case '=': 237 /* 238 * sort of a hack - expand tildes in variable 239 * assignments (after the first '=' and after ':'s). 240 */ 241 STPUTC(c, expdest); 242 if (flag & EXP_VARTILDE && *p == '~') { 243 if (c == '=') { 244 if (firsteq) 245 firsteq = 0; 246 else 247 break; 248 } 249 p = exptilde(p, flag); 250 } 251 break; 252 default: 253 STPUTC(c, expdest); 254 } 255 } 256 breakloop:; 257 } 258 259 STATIC char * 260 exptilde(p, flag) 261 char *p; 262 { 263 char c, *startp = p; 264 struct passwd *pw; 265 char *home; 266 int quotes = flag & (EXP_FULL | EXP_CASE); 267 268 while (c = *p) { 269 switch(c) { 270 case CTLESC: 271 return (startp); 272 case ':': 273 if (flag & EXP_VARTILDE) 274 goto done; 275 break; 276 case '/': 277 goto done; 278 } 279 p++; 280 } 281 done: 282 *p = '\0'; 283 if (*(startp+1) == '\0') { 284 if ((home = lookupvar("HOME")) == NULL) 285 goto lose; 286 } else { 287 if ((pw = getpwnam(startp+1)) == NULL) 288 goto lose; 289 home = pw->pw_dir; 290 } 291 if (*home == '\0') 292 goto lose; 293 *p = c; 294 while (c = *home++) { 295 if (quotes && SQSYNTAX[c] == CCTL) 296 STPUTC(CTLESC, expdest); 297 STPUTC(c, expdest); 298 } 299 return (p); 300 lose: 301 *p = c; 302 return (startp); 303 } 304 305 306 /* 307 * Expand arithmetic expression. Backup to start of expression, 308 * evaluate, place result in (backed up) result, adjust string position. 309 */ 310 void 311 expari(flag) 312 { 313 char *p, *start; 314 int result; 315 int quotes = flag & (EXP_FULL | EXP_CASE); 316 317 /* 318 * This routine is slightly over-compilcated for 319 * efficiency. First we make sure there is 320 * enough space for the result, which may be bigger 321 * than the expression if we add exponentation. Next we 322 * scan backwards looking for the start of arithmetic. If the 323 * next previous character is a CTLESC character, then we 324 * have to rescan starting from the beginning since CTLESC 325 * characters have to be processed left to right. 326 */ 327 CHECKSTRSPACE(8, expdest); 328 USTPUTC('\0', expdest); 329 start = stackblock(); 330 p = expdest; 331 while (*p != CTLARI && p >= start) 332 --p; 333 if (*p != CTLARI) 334 error("missing CTLARI (shouldn't happen)"); 335 if (p > start && *(p-1) == CTLESC) 336 for (p = start; *p != CTLARI; p++) 337 if (*p == CTLESC) 338 p++; 339 if (quotes) 340 rmescapes(p+1); 341 result = arith(p+1); 342 fmtstr(p, 10, "%d", result); 343 while (*p++) 344 ; 345 result = expdest - p + 1; 346 STADJUST(-result, expdest); 347 } 348 349 350 /* 351 * Expand stuff in backwards quotes. 352 */ 353 354 STATIC void 355 expbackq(cmd, quoted, flag) 356 union node *cmd; 357 { 358 struct backcmd in; 359 int i; 360 char buf[128]; 361 char *p; 362 char *dest = expdest; 363 struct ifsregion saveifs, *savelastp; 364 struct nodelist *saveargbackq; 365 char lastc; 366 int startloc = dest - stackblock(); 367 char const *syntax = quoted? DQSYNTAX : BASESYNTAX; 368 int saveherefd; 369 int quotes = flag & (EXP_FULL | EXP_CASE); 370 371 INTOFF; 372 saveifs = ifsfirst; 373 savelastp = ifslastp; 374 saveargbackq = argbackq; 375 saveherefd = herefd; 376 herefd = -1; 377 p = grabstackstr(dest); 378 evalbackcmd(cmd, &in); 379 ungrabstackstr(p, dest); 380 ifsfirst = saveifs; 381 ifslastp = savelastp; 382 argbackq = saveargbackq; 383 herefd = saveherefd; 384 385 p = in.buf; 386 lastc = '\0'; 387 for (;;) { 388 if (--in.nleft < 0) { 389 if (in.fd < 0) 390 break; 391 while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR); 392 TRACE(("expbackq: read returns %d\n", i)); 393 if (i <= 0) 394 break; 395 p = buf; 396 in.nleft = i - 1; 397 } 398 lastc = *p++; 399 if (lastc != '\0') { 400 if (quotes && syntax[lastc] == CCTL) 401 STPUTC(CTLESC, dest); 402 STPUTC(lastc, dest); 403 } 404 } 405 p--; 406 while (lastc == '\n') { 407 STUNPUTC(dest); 408 lastc = *--p; 409 } 410 if (in.fd >= 0) 411 close(in.fd); 412 if (in.buf) 413 ckfree(in.buf); 414 if (in.jp) 415 exitstatus = waitforjob(in.jp); 416 if (quoted == 0) 417 recordregion(startloc, dest - stackblock(), 0); 418 TRACE(("evalbackq: size=%d: \"%.*s\"\n", 419 (dest - stackblock()) - startloc, 420 (dest - stackblock()) - startloc, 421 stackblock() + startloc)); 422 expdest = dest; 423 INTON; 424 } 425 426 427 428 /* 429 * Expand a variable, and return a pointer to the next character in the 430 * input string. 431 */ 432 433 STATIC char * 434 evalvar(p, flag) 435 char *p; 436 { 437 int subtype; 438 int varflags; 439 char *var; 440 char *val; 441 int c; 442 int set; 443 int special; 444 int startloc; 445 int quotes = flag & (EXP_FULL | EXP_CASE); 446 447 varflags = *p++; 448 subtype = varflags & VSTYPE; 449 var = p; 450 special = 0; 451 if (! is_name(*p)) 452 special = 1; 453 p = strchr(p, '=') + 1; 454 again: /* jump here after setting a variable with ${var=text} */ 455 if (special) { 456 set = varisset(*var); 457 val = NULL; 458 } else { 459 val = lookupvar(var); 460 if (val == NULL || (varflags & VSNUL) && val[0] == '\0') { 461 val = NULL; 462 set = 0; 463 } else 464 set = 1; 465 } 466 startloc = expdest - stackblock(); 467 if (set && subtype != VSPLUS) { 468 /* insert the value of the variable */ 469 if (special) { 470 varvalue(*var, varflags & VSQUOTE, flag & EXP_FULL); 471 } else { 472 char const *syntax = (varflags & VSQUOTE)? DQSYNTAX : BASESYNTAX; 473 474 while (*val) { 475 if (quotes && syntax[*val] == CCTL) 476 STPUTC(CTLESC, expdest); 477 STPUTC(*val++, expdest); 478 } 479 } 480 } 481 if (subtype == VSPLUS) 482 set = ! set; 483 if (((varflags & VSQUOTE) == 0 || (*var == '@' && shellparam.nparam != 1)) 484 && (set || subtype == VSNORMAL)) 485 recordregion(startloc, expdest - stackblock(), varflags & VSQUOTE); 486 if (! set && subtype != VSNORMAL) { 487 if (subtype == VSPLUS || subtype == VSMINUS) { 488 argstr(p, flag); 489 } else { 490 char *startp; 491 int saveherefd = herefd; 492 struct nodelist *saveargbackq = argbackq; 493 herefd = -1; 494 argstr(p, 0); 495 STACKSTRNUL(expdest); 496 herefd = saveherefd; 497 argbackq = saveargbackq; 498 startp = stackblock() + startloc; 499 if (subtype == VSASSIGN) { 500 setvar(var, startp, 0); 501 STADJUST(startp - expdest, expdest); 502 varflags &=~ VSNUL; 503 goto again; 504 } 505 /* subtype == VSQUESTION */ 506 if (*p != CTLENDVAR) { 507 outfmt(&errout, "%s\n", startp); 508 error((char *)NULL); 509 } 510 error("%.*s: parameter %snot set", p - var - 1, 511 var, (varflags & VSNUL)? "null or " : nullstr); 512 } 513 } 514 if (subtype != VSNORMAL) { /* skip to end of alternative */ 515 int nesting = 1; 516 for (;;) { 517 if ((c = *p++) == CTLESC) 518 p++; 519 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { 520 if (set) 521 argbackq = argbackq->next; 522 } else if (c == CTLVAR) { 523 if ((*p++ & VSTYPE) != VSNORMAL) 524 nesting++; 525 } else if (c == CTLENDVAR) { 526 if (--nesting == 0) 527 break; 528 } 529 } 530 } 531 return p; 532 } 533 534 535 536 /* 537 * Test whether a specialized variable is set. 538 */ 539 540 STATIC int 541 varisset(name) 542 char name; 543 { 544 char **ap; 545 546 if (name == '!') { 547 if (backgndpid == -1) 548 return 0; 549 } else if (name == '@' || name == '*') { 550 if (*shellparam.p == NULL) 551 return 0; 552 } else if ((unsigned)(name -= '1') <= '9' - '1') { 553 ap = shellparam.p; 554 do { 555 if (*ap++ == NULL) 556 return 0; 557 } while (--name >= 0); 558 } 559 return 1; 560 } 561 562 563 564 /* 565 * Add the value of a specialized variable to the stack string. 566 */ 567 568 STATIC void 569 varvalue(name, quoted, allow_split) 570 char name; 571 { 572 int num; 573 char temp[32]; 574 char *p; 575 int i; 576 extern int exitstatus; 577 char sep; 578 char **ap; 579 char const *syntax; 580 581 #define STRTODEST(p) \ 582 do {\ 583 if (allow_split) { \ 584 syntax = quoted? DQSYNTAX : BASESYNTAX; \ 585 while (*p) { \ 586 if (syntax[*p] == CCTL) \ 587 STPUTC(CTLESC, expdest); \ 588 STPUTC(*p++, expdest); \ 589 } \ 590 } else \ 591 while (*p) \ 592 STPUTC(*p++, expdest); \ 593 } while (0) 594 595 596 switch (name) { 597 case '$': 598 num = rootpid; 599 goto numvar; 600 case '?': 601 num = exitstatus; 602 goto numvar; 603 case '#': 604 num = shellparam.nparam; 605 goto numvar; 606 case '!': 607 num = backgndpid; 608 numvar: 609 p = temp + 31; 610 temp[31] = '\0'; 611 do { 612 *--p = num % 10 + '0'; 613 } while ((num /= 10) != 0); 614 while (*p) 615 STPUTC(*p++, expdest); 616 break; 617 case '-': 618 for (i = 0 ; i < NOPTS ; i++) { 619 if (optlist[i].val) 620 STPUTC(optlist[i].letter, expdest); 621 } 622 break; 623 case '@': 624 if (allow_split) { 625 sep = '\0'; 626 goto allargs; 627 } 628 /* fall through */ 629 case '*': 630 sep = ' '; 631 allargs: 632 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 633 STRTODEST(p); 634 if (*ap) 635 STPUTC(sep, expdest); 636 } 637 break; 638 case '0': 639 p = arg0; 640 STRTODEST(p); 641 break; 642 default: 643 if ((unsigned)(name -= '1') <= '9' - '1') { 644 p = shellparam.p[name]; 645 STRTODEST(p); 646 } 647 break; 648 } 649 } 650 651 652 653 /* 654 * Record the the fact that we have to scan this region of the 655 * string for IFS characters. 656 */ 657 658 STATIC void 659 recordregion(start, end, nulonly) { 660 register struct ifsregion *ifsp; 661 662 if (ifslastp == NULL) { 663 ifsp = &ifsfirst; 664 } else { 665 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 666 ifslastp->next = ifsp; 667 } 668 ifslastp = ifsp; 669 ifslastp->next = NULL; 670 ifslastp->begoff = start; 671 ifslastp->endoff = end; 672 ifslastp->nulonly = nulonly; 673 } 674 675 676 677 /* 678 * Break the argument string into pieces based upon IFS and add the 679 * strings to the argument list. The regions of the string to be 680 * searched for IFS characters have been stored by recordregion. 681 */ 682 683 STATIC void 684 ifsbreakup(string, arglist) 685 char *string; 686 struct arglist *arglist; 687 { 688 struct ifsregion *ifsp; 689 struct strlist *sp; 690 char *start; 691 register char *p; 692 char *q; 693 char *ifs; 694 695 start = string; 696 if (ifslastp != NULL) { 697 ifsp = &ifsfirst; 698 do { 699 p = string + ifsp->begoff; 700 ifs = ifsp->nulonly? nullstr : ifsval(); 701 while (p < string + ifsp->endoff) { 702 q = p; 703 if (*p == CTLESC) 704 p++; 705 if (strchr(ifs, *p++)) { 706 if (q > start || *ifs != ' ') { 707 *q = '\0'; 708 sp = (struct strlist *)stalloc(sizeof *sp); 709 sp->text = start; 710 *arglist->lastp = sp; 711 arglist->lastp = &sp->next; 712 } 713 if (*ifs == ' ') { 714 for (;;) { 715 if (p >= string + ifsp->endoff) 716 break; 717 q = p; 718 if (*p == CTLESC) 719 p++; 720 if (strchr(ifs, *p++) == NULL) { 721 p = q; 722 break; 723 } 724 } 725 } 726 start = p; 727 } 728 } 729 } while ((ifsp = ifsp->next) != NULL); 730 if (*start || (*ifs != ' ' && start > string)) { 731 sp = (struct strlist *)stalloc(sizeof *sp); 732 sp->text = start; 733 *arglist->lastp = sp; 734 arglist->lastp = &sp->next; 735 } 736 } else { 737 sp = (struct strlist *)stalloc(sizeof *sp); 738 sp->text = start; 739 *arglist->lastp = sp; 740 arglist->lastp = &sp->next; 741 } 742 } 743 744 745 746 /* 747 * Expand shell metacharacters. At this point, the only control characters 748 * should be escapes. The results are stored in the list exparg. 749 */ 750 751 char *expdir; 752 753 754 STATIC void 755 expandmeta(str, flag) 756 struct strlist *str; 757 { 758 char *p; 759 struct strlist **savelastp; 760 struct strlist *sp; 761 char c; 762 /* TODO - EXP_REDIR */ 763 764 while (str) { 765 if (fflag) 766 goto nometa; 767 p = str->text; 768 for (;;) { /* fast check for meta chars */ 769 if ((c = *p++) == '\0') 770 goto nometa; 771 if (c == '*' || c == '?' || c == '[' || c == '!') 772 break; 773 } 774 savelastp = exparg.lastp; 775 INTOFF; 776 if (expdir == NULL) { 777 int i = strlen(str->text); 778 expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */ 779 } 780 781 expmeta(expdir, str->text); 782 ckfree(expdir); 783 expdir = NULL; 784 INTON; 785 if (exparg.lastp == savelastp) { 786 /* 787 * no matches 788 */ 789 nometa: 790 *exparg.lastp = str; 791 rmescapes(str->text); 792 exparg.lastp = &str->next; 793 } else { 794 *exparg.lastp = NULL; 795 *savelastp = sp = expsort(*savelastp); 796 while (sp->next != NULL) 797 sp = sp->next; 798 exparg.lastp = &sp->next; 799 } 800 str = str->next; 801 } 802 } 803 804 805 /* 806 * Do metacharacter (i.e. *, ?, [...]) expansion. 807 */ 808 809 STATIC void 810 expmeta(enddir, name) 811 char *enddir; 812 char *name; 813 { 814 register char *p; 815 char *q; 816 char *start; 817 char *endname; 818 int metaflag; 819 struct stat statb; 820 DIR *dirp; 821 struct dirent *dp; 822 int atend; 823 int matchdot; 824 825 metaflag = 0; 826 start = name; 827 for (p = name ; ; p++) { 828 if (*p == '*' || *p == '?') 829 metaflag = 1; 830 else if (*p == '[') { 831 q = p + 1; 832 if (*q == '!') 833 q++; 834 for (;;) { 835 if (*q == CTLESC) 836 q++; 837 if (*q == '/' || *q == '\0') 838 break; 839 if (*++q == ']') { 840 metaflag = 1; 841 break; 842 } 843 } 844 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 845 metaflag = 1; 846 } else if (*p == '\0') 847 break; 848 else if (*p == CTLESC) 849 p++; 850 if (*p == '/') { 851 if (metaflag) 852 break; 853 start = p + 1; 854 } 855 } 856 if (metaflag == 0) { /* we've reached the end of the file name */ 857 if (enddir != expdir) 858 metaflag++; 859 for (p = name ; ; p++) { 860 if (*p == CTLESC) 861 p++; 862 *enddir++ = *p; 863 if (*p == '\0') 864 break; 865 } 866 if (metaflag == 0 || stat(expdir, &statb) >= 0) 867 addfname(expdir); 868 return; 869 } 870 endname = p; 871 if (start != name) { 872 p = name; 873 while (p < start) { 874 if (*p == CTLESC) 875 p++; 876 *enddir++ = *p++; 877 } 878 } 879 if (enddir == expdir) { 880 p = "."; 881 } else if (enddir == expdir + 1 && *expdir == '/') { 882 p = "/"; 883 } else { 884 p = expdir; 885 enddir[-1] = '\0'; 886 } 887 if ((dirp = opendir(p)) == NULL) 888 return; 889 if (enddir != expdir) 890 enddir[-1] = '/'; 891 if (*endname == 0) { 892 atend = 1; 893 } else { 894 atend = 0; 895 *endname++ = '\0'; 896 } 897 matchdot = 0; 898 if (start[0] == '.' || start[0] == CTLESC && start[1] == '.') 899 matchdot++; 900 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 901 if (dp->d_name[0] == '.' && ! matchdot) 902 continue; 903 if (patmatch(start, dp->d_name)) { 904 if (atend) { 905 scopy(dp->d_name, enddir); 906 addfname(expdir); 907 } else { 908 char *q; 909 for (p = enddir, q = dp->d_name ; *p++ = *q++ ;); 910 p[-1] = '/'; 911 expmeta(p, endname); 912 } 913 } 914 } 915 closedir(dirp); 916 if (! atend) 917 endname[-1] = '/'; 918 } 919 920 921 /* 922 * Add a file name to the list. 923 */ 924 925 STATIC void 926 addfname(name) 927 char *name; 928 { 929 char *p; 930 struct strlist *sp; 931 932 p = stalloc(strlen(name) + 1); 933 scopy(name, p); 934 sp = (struct strlist *)stalloc(sizeof *sp); 935 sp->text = p; 936 *exparg.lastp = sp; 937 exparg.lastp = &sp->next; 938 } 939 940 941 /* 942 * Sort the results of file name expansion. It calculates the number of 943 * strings to sort and then calls msort (short for merge sort) to do the 944 * work. 945 */ 946 947 STATIC struct strlist * 948 expsort(str) 949 struct strlist *str; 950 { 951 int len; 952 struct strlist *sp; 953 954 len = 0; 955 for (sp = str ; sp ; sp = sp->next) 956 len++; 957 return msort(str, len); 958 } 959 960 961 STATIC struct strlist * 962 msort(list, len) 963 struct strlist *list; 964 { 965 struct strlist *p, *q; 966 struct strlist **lpp; 967 int half; 968 int n; 969 970 if (len <= 1) 971 return list; 972 half = len >> 1; 973 p = list; 974 for (n = half ; --n >= 0 ; ) { 975 q = p; 976 p = p->next; 977 } 978 q->next = NULL; /* terminate first half of list */ 979 q = msort(list, half); /* sort first half of list */ 980 p = msort(p, len - half); /* sort second half */ 981 lpp = &list; 982 for (;;) { 983 if (strcmp(p->text, q->text) < 0) { 984 *lpp = p; 985 lpp = &p->next; 986 if ((p = *lpp) == NULL) { 987 *lpp = q; 988 break; 989 } 990 } else { 991 *lpp = q; 992 lpp = &q->next; 993 if ((q = *lpp) == NULL) { 994 *lpp = p; 995 break; 996 } 997 } 998 } 999 return list; 1000 } 1001 1002 1003 1004 /* 1005 * Returns true if the pattern matches the string. 1006 */ 1007 1008 int 1009 patmatch(pattern, string) 1010 char *pattern; 1011 char *string; 1012 { 1013 #ifdef notdef 1014 if (pattern[0] == '!' && pattern[1] == '!') 1015 return 1 - pmatch(pattern + 2, string); 1016 else 1017 #endif 1018 return pmatch(pattern, string); 1019 } 1020 1021 1022 STATIC int 1023 pmatch(pattern, string) 1024 char *pattern; 1025 char *string; 1026 { 1027 register char *p, *q; 1028 register char c; 1029 1030 p = pattern; 1031 q = string; 1032 for (;;) { 1033 switch (c = *p++) { 1034 case '\0': 1035 goto breakloop; 1036 case CTLESC: 1037 if (*q++ != *p++) 1038 return 0; 1039 break; 1040 case '?': 1041 if (*q++ == '\0') 1042 return 0; 1043 break; 1044 case '*': 1045 c = *p; 1046 if (c != CTLESC && c != '?' && c != '*' && c != '[') { 1047 while (*q != c) { 1048 if (*q == '\0') 1049 return 0; 1050 q++; 1051 } 1052 } 1053 do { 1054 if (pmatch(p, q)) 1055 return 1; 1056 } while (*q++ != '\0'); 1057 return 0; 1058 case '[': { 1059 char *endp; 1060 int invert, found; 1061 char chr; 1062 1063 endp = p; 1064 if (*endp == '!') 1065 endp++; 1066 for (;;) { 1067 if (*endp == '\0') 1068 goto dft; /* no matching ] */ 1069 if (*endp == CTLESC) 1070 endp++; 1071 if (*++endp == ']') 1072 break; 1073 } 1074 invert = 0; 1075 if (*p == '!') { 1076 invert++; 1077 p++; 1078 } 1079 found = 0; 1080 chr = *q++; 1081 c = *p++; 1082 do { 1083 if (c == CTLESC) 1084 c = *p++; 1085 if (*p == '-' && p[1] != ']') { 1086 p++; 1087 if (*p == CTLESC) 1088 p++; 1089 if (chr >= c && chr <= *p) 1090 found = 1; 1091 p++; 1092 } else { 1093 if (chr == c) 1094 found = 1; 1095 } 1096 } while ((c = *p++) != ']'); 1097 if (found == invert) 1098 return 0; 1099 break; 1100 } 1101 dft: default: 1102 if (*q++ != c) 1103 return 0; 1104 break; 1105 } 1106 } 1107 breakloop: 1108 if (*q != '\0') 1109 return 0; 1110 return 1; 1111 } 1112 1113 1114 1115 /* 1116 * Remove any CTLESC characters from a string. 1117 */ 1118 1119 void 1120 rmescapes(str) 1121 char *str; 1122 { 1123 register char *p, *q; 1124 1125 p = str; 1126 while (*p != CTLESC) { 1127 if (*p++ == '\0') 1128 return; 1129 } 1130 q = p; 1131 while (*p) { 1132 if (*p == CTLESC) 1133 p++; 1134 *q++ = *p++; 1135 } 1136 *q = '\0'; 1137 } 1138 1139 1140 1141 /* 1142 * See if a pattern matches in a case statement. 1143 */ 1144 1145 int 1146 casematch(pattern, val) 1147 union node *pattern; 1148 char *val; 1149 { 1150 struct stackmark smark; 1151 int result; 1152 char *p; 1153 1154 setstackmark(&smark); 1155 argbackq = pattern->narg.backquote; 1156 STARTSTACKSTR(expdest); 1157 ifslastp = NULL; 1158 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); 1159 STPUTC('\0', expdest); 1160 p = grabstackstr(expdest); 1161 result = patmatch(p, val); 1162 popstackmark(&smark); 1163 return result; 1164 } 1165