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 * $Id$ 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 if (lastc == '\n') { 406 STUNPUTC(dest); 407 } 408 if (in.fd >= 0) 409 close(in.fd); 410 if (in.buf) 411 ckfree(in.buf); 412 if (in.jp) 413 exitstatus = waitforjob(in.jp); 414 if (quoted == 0) 415 recordregion(startloc, dest - stackblock(), 0); 416 TRACE(("evalbackq: size=%d: \"%.*s\"\n", 417 (dest - stackblock()) - startloc, 418 (dest - stackblock()) - startloc, 419 stackblock() + startloc)); 420 expdest = dest; 421 INTON; 422 } 423 424 425 426 /* 427 * Expand a variable, and return a pointer to the next character in the 428 * input string. 429 */ 430 431 STATIC char * 432 evalvar(p, flag) 433 char *p; 434 { 435 int subtype; 436 int varflags; 437 char *var; 438 char *val; 439 int c; 440 int set; 441 int special; 442 int startloc; 443 int quotes = flag & (EXP_FULL | EXP_CASE); 444 445 varflags = *p++; 446 subtype = varflags & VSTYPE; 447 var = p; 448 special = 0; 449 if (! is_name(*p)) 450 special = 1; 451 p = strchr(p, '=') + 1; 452 again: /* jump here after setting a variable with ${var=text} */ 453 if (special) { 454 set = varisset(*var); 455 val = NULL; 456 } else { 457 val = lookupvar(var); 458 if (val == NULL || (varflags & VSNUL) && val[0] == '\0') { 459 val = NULL; 460 set = 0; 461 } else 462 set = 1; 463 } 464 startloc = expdest - stackblock(); 465 if (set && subtype != VSPLUS) { 466 /* insert the value of the variable */ 467 if (special) { 468 varvalue(*var, varflags & VSQUOTE, flag & EXP_FULL); 469 } else { 470 char const *syntax = (varflags & VSQUOTE)? DQSYNTAX : BASESYNTAX; 471 472 while (*val) { 473 if (quotes && syntax[*val] == CCTL) 474 STPUTC(CTLESC, expdest); 475 STPUTC(*val++, expdest); 476 } 477 } 478 } 479 if (subtype == VSPLUS) 480 set = ! set; 481 if (((varflags & VSQUOTE) == 0 || (*var == '@' && shellparam.nparam != 1)) 482 && (set || subtype == VSNORMAL)) 483 recordregion(startloc, expdest - stackblock(), varflags & VSQUOTE); 484 if (! set && subtype != VSNORMAL) { 485 if (subtype == VSPLUS || subtype == VSMINUS) { 486 argstr(p, flag); 487 } else { 488 char *startp; 489 int saveherefd = herefd; 490 struct nodelist *saveargbackq = argbackq; 491 herefd = -1; 492 argstr(p, 0); 493 STACKSTRNUL(expdest); 494 herefd = saveherefd; 495 argbackq = saveargbackq; 496 startp = stackblock() + startloc; 497 if (subtype == VSASSIGN) { 498 setvar(var, startp, 0); 499 STADJUST(startp - expdest, expdest); 500 varflags &=~ VSNUL; 501 goto again; 502 } 503 /* subtype == VSQUESTION */ 504 if (*p != CTLENDVAR) { 505 outfmt(&errout, "%s\n", startp); 506 error((char *)NULL); 507 } 508 error("%.*s: parameter %snot set", p - var - 1, 509 var, (varflags & VSNUL)? "null or " : nullstr); 510 } 511 } 512 if (subtype != VSNORMAL) { /* skip to end of alternative */ 513 int nesting = 1; 514 for (;;) { 515 if ((c = *p++) == CTLESC) 516 p++; 517 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { 518 if (set) 519 argbackq = argbackq->next; 520 } else if (c == CTLVAR) { 521 if ((*p++ & VSTYPE) != VSNORMAL) 522 nesting++; 523 } else if (c == CTLENDVAR) { 524 if (--nesting == 0) 525 break; 526 } 527 } 528 } 529 return p; 530 } 531 532 533 534 /* 535 * Test whether a specialized variable is set. 536 */ 537 538 STATIC int 539 varisset(name) 540 char name; 541 { 542 char **ap; 543 544 if (name == '!') { 545 if (backgndpid == -1) 546 return 0; 547 } else if (name == '@' || name == '*') { 548 if (*shellparam.p == NULL) 549 return 0; 550 } else if ((unsigned)(name -= '1') <= '9' - '1') { 551 ap = shellparam.p; 552 do { 553 if (*ap++ == NULL) 554 return 0; 555 } while (--name >= 0); 556 } 557 return 1; 558 } 559 560 561 562 /* 563 * Add the value of a specialized variable to the stack string. 564 */ 565 566 STATIC void 567 varvalue(name, quoted, allow_split) 568 char name; 569 { 570 int num; 571 char temp[32]; 572 char *p; 573 int i; 574 extern int exitstatus; 575 char sep; 576 char **ap; 577 char const *syntax; 578 579 #define STRTODEST(p) \ 580 do {\ 581 if (allow_split) { \ 582 syntax = quoted? DQSYNTAX : BASESYNTAX; \ 583 while (*p) { \ 584 if (syntax[*p] == CCTL) \ 585 STPUTC(CTLESC, expdest); \ 586 STPUTC(*p++, expdest); \ 587 } \ 588 } else \ 589 while (*p) \ 590 STPUTC(*p++, expdest); \ 591 } while (0) 592 593 594 switch (name) { 595 case '$': 596 num = rootpid; 597 goto numvar; 598 case '?': 599 num = exitstatus; 600 goto numvar; 601 case '#': 602 num = shellparam.nparam; 603 goto numvar; 604 case '!': 605 num = backgndpid; 606 numvar: 607 p = temp + 31; 608 temp[31] = '\0'; 609 do { 610 *--p = num % 10 + '0'; 611 } while ((num /= 10) != 0); 612 while (*p) 613 STPUTC(*p++, expdest); 614 break; 615 case '-': 616 for (i = 0 ; i < NOPTS ; i++) { 617 if (optlist[i].val) 618 STPUTC(optlist[i].letter, expdest); 619 } 620 break; 621 case '@': 622 if (allow_split) { 623 sep = '\0'; 624 goto allargs; 625 } 626 /* fall through */ 627 case '*': 628 sep = ' '; 629 allargs: 630 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 631 STRTODEST(p); 632 if (*ap) 633 STPUTC(sep, expdest); 634 } 635 break; 636 case '0': 637 p = arg0; 638 STRTODEST(p); 639 break; 640 default: 641 if ((unsigned)(name -= '1') <= '9' - '1') { 642 p = shellparam.p[name]; 643 STRTODEST(p); 644 } 645 break; 646 } 647 } 648 649 650 651 /* 652 * Record the the fact that we have to scan this region of the 653 * string for IFS characters. 654 */ 655 656 STATIC void 657 recordregion(start, end, nulonly) { 658 register struct ifsregion *ifsp; 659 660 if (ifslastp == NULL) { 661 ifsp = &ifsfirst; 662 } else { 663 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 664 ifslastp->next = ifsp; 665 } 666 ifslastp = ifsp; 667 ifslastp->next = NULL; 668 ifslastp->begoff = start; 669 ifslastp->endoff = end; 670 ifslastp->nulonly = nulonly; 671 } 672 673 674 675 /* 676 * Break the argument string into pieces based upon IFS and add the 677 * strings to the argument list. The regions of the string to be 678 * searched for IFS characters have been stored by recordregion. 679 */ 680 681 STATIC void 682 ifsbreakup(string, arglist) 683 char *string; 684 struct arglist *arglist; 685 { 686 struct ifsregion *ifsp; 687 struct strlist *sp; 688 char *start; 689 register char *p; 690 char *q; 691 char *ifs; 692 693 start = string; 694 if (ifslastp != NULL) { 695 ifsp = &ifsfirst; 696 do { 697 p = string + ifsp->begoff; 698 ifs = ifsp->nulonly? nullstr : ifsval(); 699 while (p < string + ifsp->endoff) { 700 q = p; 701 if (*p == CTLESC) 702 p++; 703 if (strchr(ifs, *p++)) { 704 if (q > start || *ifs != ' ') { 705 *q = '\0'; 706 sp = (struct strlist *)stalloc(sizeof *sp); 707 sp->text = start; 708 *arglist->lastp = sp; 709 arglist->lastp = &sp->next; 710 } 711 if (*ifs == ' ') { 712 for (;;) { 713 if (p >= string + ifsp->endoff) 714 break; 715 q = p; 716 if (*p == CTLESC) 717 p++; 718 if (strchr(ifs, *p++) == NULL) { 719 p = q; 720 break; 721 } 722 } 723 } 724 start = p; 725 } 726 } 727 } while ((ifsp = ifsp->next) != NULL); 728 if (*start || (*ifs != ' ' && start > string)) { 729 sp = (struct strlist *)stalloc(sizeof *sp); 730 sp->text = start; 731 *arglist->lastp = sp; 732 arglist->lastp = &sp->next; 733 } 734 } else { 735 sp = (struct strlist *)stalloc(sizeof *sp); 736 sp->text = start; 737 *arglist->lastp = sp; 738 arglist->lastp = &sp->next; 739 } 740 } 741 742 743 744 /* 745 * Expand shell metacharacters. At this point, the only control characters 746 * should be escapes. The results are stored in the list exparg. 747 */ 748 749 char *expdir; 750 751 752 STATIC void 753 expandmeta(str, flag) 754 struct strlist *str; 755 { 756 char *p; 757 struct strlist **savelastp; 758 struct strlist *sp; 759 char c; 760 /* TODO - EXP_REDIR */ 761 762 while (str) { 763 if (fflag) 764 goto nometa; 765 p = str->text; 766 for (;;) { /* fast check for meta chars */ 767 if ((c = *p++) == '\0') 768 goto nometa; 769 if (c == '*' || c == '?' || c == '[' || c == '!') 770 break; 771 } 772 savelastp = exparg.lastp; 773 INTOFF; 774 if (expdir == NULL) { 775 int i = strlen(str->text); 776 expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */ 777 } 778 779 expmeta(expdir, str->text); 780 ckfree(expdir); 781 expdir = NULL; 782 INTON; 783 if (exparg.lastp == savelastp) { 784 /* 785 * no matches 786 */ 787 nometa: 788 *exparg.lastp = str; 789 rmescapes(str->text); 790 exparg.lastp = &str->next; 791 } else { 792 *exparg.lastp = NULL; 793 *savelastp = sp = expsort(*savelastp); 794 while (sp->next != NULL) 795 sp = sp->next; 796 exparg.lastp = &sp->next; 797 } 798 str = str->next; 799 } 800 } 801 802 803 /* 804 * Do metacharacter (i.e. *, ?, [...]) expansion. 805 */ 806 807 STATIC void 808 expmeta(enddir, name) 809 char *enddir; 810 char *name; 811 { 812 register char *p; 813 char *q; 814 char *start; 815 char *endname; 816 int metaflag; 817 struct stat statb; 818 DIR *dirp; 819 struct dirent *dp; 820 int atend; 821 int matchdot; 822 823 metaflag = 0; 824 start = name; 825 for (p = name ; ; p++) { 826 if (*p == '*' || *p == '?') 827 metaflag = 1; 828 else if (*p == '[') { 829 q = p + 1; 830 if (*q == '!') 831 q++; 832 for (;;) { 833 if (*q == CTLESC) 834 q++; 835 if (*q == '/' || *q == '\0') 836 break; 837 if (*++q == ']') { 838 metaflag = 1; 839 break; 840 } 841 } 842 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 843 metaflag = 1; 844 } else if (*p == '\0') 845 break; 846 else if (*p == CTLESC) 847 p++; 848 if (*p == '/') { 849 if (metaflag) 850 break; 851 start = p + 1; 852 } 853 } 854 if (metaflag == 0) { /* we've reached the end of the file name */ 855 if (enddir != expdir) 856 metaflag++; 857 for (p = name ; ; p++) { 858 if (*p == CTLESC) 859 p++; 860 *enddir++ = *p; 861 if (*p == '\0') 862 break; 863 } 864 if (metaflag == 0 || stat(expdir, &statb) >= 0) 865 addfname(expdir); 866 return; 867 } 868 endname = p; 869 if (start != name) { 870 p = name; 871 while (p < start) { 872 if (*p == CTLESC) 873 p++; 874 *enddir++ = *p++; 875 } 876 } 877 if (enddir == expdir) { 878 p = "."; 879 } else if (enddir == expdir + 1 && *expdir == '/') { 880 p = "/"; 881 } else { 882 p = expdir; 883 enddir[-1] = '\0'; 884 } 885 if ((dirp = opendir(p)) == NULL) 886 return; 887 if (enddir != expdir) 888 enddir[-1] = '/'; 889 if (*endname == 0) { 890 atend = 1; 891 } else { 892 atend = 0; 893 *endname++ = '\0'; 894 } 895 matchdot = 0; 896 if (start[0] == '.' || start[0] == CTLESC && start[1] == '.') 897 matchdot++; 898 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 899 if (dp->d_name[0] == '.' && ! matchdot) 900 continue; 901 if (patmatch(start, dp->d_name)) { 902 if (atend) { 903 scopy(dp->d_name, enddir); 904 addfname(expdir); 905 } else { 906 char *q; 907 for (p = enddir, q = dp->d_name ; *p++ = *q++ ;); 908 p[-1] = '/'; 909 expmeta(p, endname); 910 } 911 } 912 } 913 closedir(dirp); 914 if (! atend) 915 endname[-1] = '/'; 916 } 917 918 919 /* 920 * Add a file name to the list. 921 */ 922 923 STATIC void 924 addfname(name) 925 char *name; 926 { 927 char *p; 928 struct strlist *sp; 929 930 p = stalloc(strlen(name) + 1); 931 scopy(name, p); 932 sp = (struct strlist *)stalloc(sizeof *sp); 933 sp->text = p; 934 *exparg.lastp = sp; 935 exparg.lastp = &sp->next; 936 } 937 938 939 /* 940 * Sort the results of file name expansion. It calculates the number of 941 * strings to sort and then calls msort (short for merge sort) to do the 942 * work. 943 */ 944 945 STATIC struct strlist * 946 expsort(str) 947 struct strlist *str; 948 { 949 int len; 950 struct strlist *sp; 951 952 len = 0; 953 for (sp = str ; sp ; sp = sp->next) 954 len++; 955 return msort(str, len); 956 } 957 958 959 STATIC struct strlist * 960 msort(list, len) 961 struct strlist *list; 962 { 963 struct strlist *p, *q; 964 struct strlist **lpp; 965 int half; 966 int n; 967 968 if (len <= 1) 969 return list; 970 half = len >> 1; 971 p = list; 972 for (n = half ; --n >= 0 ; ) { 973 q = p; 974 p = p->next; 975 } 976 q->next = NULL; /* terminate first half of list */ 977 q = msort(list, half); /* sort first half of list */ 978 p = msort(p, len - half); /* sort second half */ 979 lpp = &list; 980 for (;;) { 981 if (strcmp(p->text, q->text) < 0) { 982 *lpp = p; 983 lpp = &p->next; 984 if ((p = *lpp) == NULL) { 985 *lpp = q; 986 break; 987 } 988 } else { 989 *lpp = q; 990 lpp = &q->next; 991 if ((q = *lpp) == NULL) { 992 *lpp = p; 993 break; 994 } 995 } 996 } 997 return list; 998 } 999 1000 1001 1002 /* 1003 * Returns true if the pattern matches the string. 1004 */ 1005 1006 int 1007 patmatch(pattern, string) 1008 char *pattern; 1009 char *string; 1010 { 1011 #ifdef notdef 1012 if (pattern[0] == '!' && pattern[1] == '!') 1013 return 1 - pmatch(pattern + 2, string); 1014 else 1015 #endif 1016 return pmatch(pattern, string); 1017 } 1018 1019 1020 STATIC int 1021 pmatch(pattern, string) 1022 char *pattern; 1023 char *string; 1024 { 1025 register char *p, *q; 1026 register char c; 1027 1028 p = pattern; 1029 q = string; 1030 for (;;) { 1031 switch (c = *p++) { 1032 case '\0': 1033 goto breakloop; 1034 case CTLESC: 1035 if (*q++ != *p++) 1036 return 0; 1037 break; 1038 case '?': 1039 if (*q++ == '\0') 1040 return 0; 1041 break; 1042 case '*': 1043 c = *p; 1044 if (c != CTLESC && c != '?' && c != '*' && c != '[') { 1045 while (*q != c) { 1046 if (*q == '\0') 1047 return 0; 1048 q++; 1049 } 1050 } 1051 do { 1052 if (pmatch(p, q)) 1053 return 1; 1054 } while (*q++ != '\0'); 1055 return 0; 1056 case '[': { 1057 char *endp; 1058 int invert, found; 1059 char chr; 1060 1061 endp = p; 1062 if (*endp == '!') 1063 endp++; 1064 for (;;) { 1065 if (*endp == '\0') 1066 goto dft; /* no matching ] */ 1067 if (*endp == CTLESC) 1068 endp++; 1069 if (*++endp == ']') 1070 break; 1071 } 1072 invert = 0; 1073 if (*p == '!') { 1074 invert++; 1075 p++; 1076 } 1077 found = 0; 1078 chr = *q++; 1079 c = *p++; 1080 do { 1081 if (c == CTLESC) 1082 c = *p++; 1083 if (*p == '-' && p[1] != ']') { 1084 p++; 1085 if (*p == CTLESC) 1086 p++; 1087 if (chr >= c && chr <= *p) 1088 found = 1; 1089 p++; 1090 } else { 1091 if (chr == c) 1092 found = 1; 1093 } 1094 } while ((c = *p++) != ']'); 1095 if (found == invert) 1096 return 0; 1097 break; 1098 } 1099 dft: default: 1100 if (*q++ != c) 1101 return 0; 1102 break; 1103 } 1104 } 1105 breakloop: 1106 if (*q != '\0') 1107 return 0; 1108 return 1; 1109 } 1110 1111 1112 1113 /* 1114 * Remove any CTLESC characters from a string. 1115 */ 1116 1117 void 1118 rmescapes(str) 1119 char *str; 1120 { 1121 register char *p, *q; 1122 1123 p = str; 1124 while (*p != CTLESC) { 1125 if (*p++ == '\0') 1126 return; 1127 } 1128 q = p; 1129 while (*p) { 1130 if (*p == CTLESC) 1131 p++; 1132 *q++ = *p++; 1133 } 1134 *q = '\0'; 1135 } 1136 1137 1138 1139 /* 1140 * See if a pattern matches in a case statement. 1141 */ 1142 1143 int 1144 casematch(pattern, val) 1145 union node *pattern; 1146 char *val; 1147 { 1148 struct stackmark smark; 1149 int result; 1150 char *p; 1151 1152 setstackmark(&smark); 1153 argbackq = pattern->narg.backquote; 1154 STARTSTACKSTR(expdest); 1155 ifslastp = NULL; 1156 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); 1157 STPUTC('\0', expdest); 1158 p = grabstackstr(expdest); 1159 result = patmatch(p, val); 1160 popstackmark(&smark); 1161 return result; 1162 } 1163