1 /*- 2 * Copyright (c) 1991 The Regents of the University of California. 3 * 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[] = "from: @(#)expand.c 5.1 (Berkeley) 3/7/91";*/ 39 static char rcsid[] = "$Id: expand.c,v 1.7 1993/10/22 13:32:22 mycroft Exp $"; 40 #endif /* not lint */ 41 42 /* 43 * Routines to expand arguments to commands. We have to deal with 44 * backquotes, shell variables, and file metacharacters. 45 */ 46 47 #include "shell.h" 48 #include "main.h" 49 #include "nodes.h" 50 #include "eval.h" 51 #include "expand.h" 52 #include "syntax.h" 53 #include "parser.h" 54 #include "jobs.h" 55 #include "options.h" 56 #include "var.h" 57 #include "input.h" 58 #include "output.h" 59 #include "memalloc.h" 60 #include "error.h" 61 #include "mystring.h" 62 #include <sys/types.h> 63 #include <sys/stat.h> 64 #include <errno.h> 65 #include <dirent.h> 66 67 /* 68 * Structure specifying which parts of the string should be searched 69 * for IFS characters. 70 */ 71 72 struct ifsregion { 73 struct ifsregion *next; /* next region in list */ 74 int begoff; /* offset of start of region */ 75 int endoff; /* offset of end of region */ 76 int nulonly; /* search for nul bytes only */ 77 }; 78 79 80 char *expdest; /* output of current string */ 81 struct nodelist *argbackq; /* list of back quote expressions */ 82 struct ifsregion ifsfirst; /* first struct in list of ifs regions */ 83 struct ifsregion *ifslastp; /* last struct in list */ 84 struct arglist exparg; /* holds expanded arg list */ 85 #if UDIR 86 /* 87 * Set if the last argument processed had /u/logname expanded. This 88 * variable is read by the cd command. 89 */ 90 int didudir; 91 #endif 92 93 #ifdef __STDC__ 94 STATIC void argstr(char *, int); 95 STATIC void expbackq(union node *, int, int); 96 STATIC char *evalvar(char *, int); 97 STATIC int varisset(int); 98 STATIC void varvalue(int, int, int); 99 STATIC void recordregion(int, int, int); 100 STATIC void ifsbreakup(char *, struct arglist *); 101 STATIC void expandmeta(struct strlist *); 102 STATIC void expmeta(char *, char *); 103 STATIC void addfname(char *); 104 STATIC struct strlist *expsort(struct strlist *); 105 STATIC struct strlist *msort(struct strlist *, int); 106 STATIC int pmatch(char *, char *); 107 #else 108 STATIC void argstr(); 109 STATIC void expbackq(); 110 STATIC char *evalvar(); 111 STATIC int varisset(); 112 STATIC void varvalue(); 113 STATIC void recordregion(); 114 STATIC void ifsbreakup(); 115 STATIC void expandmeta(); 116 STATIC void expmeta(); 117 STATIC void addfname(); 118 STATIC struct strlist *expsort(); 119 STATIC struct strlist *msort(); 120 STATIC int pmatch(); 121 #endif 122 #if UDIR 123 #ifdef __STDC__ 124 STATIC char *expudir(char *); 125 #else 126 STATIC char *expudir(); 127 #endif 128 #endif /* UDIR */ 129 130 131 132 /* 133 * Expand shell variables and backquotes inside a here document. 134 */ 135 136 void 137 expandhere(arg, fd) 138 union node *arg; /* the document */ 139 int fd; /* where to write the expanded version */ 140 { 141 herefd = fd; 142 expandarg(arg, (struct arglist *)NULL, 0); 143 xwrite(fd, stackblock(), expdest - stackblock()); 144 } 145 146 147 /* 148 * Perform variable substitution and command substitution on an argument, 149 * placing the resulting list of arguments in arglist. If full is true, 150 * perform splitting and file name expansion. When arglist is NULL, perform 151 * here document expansion. 152 */ 153 154 void 155 expandarg(arg, arglist, full) 156 union node *arg; 157 struct arglist *arglist; 158 { 159 struct strlist *sp; 160 char *p; 161 162 #if UDIR 163 didudir = 0; 164 #endif 165 argbackq = arg->narg.backquote; 166 STARTSTACKSTR(expdest); 167 ifsfirst.next = NULL; 168 ifslastp = NULL; 169 argstr(arg->narg.text, full); 170 if (arglist == NULL) 171 return; /* here document expanded */ 172 STPUTC('\0', expdest); 173 p = grabstackstr(expdest); 174 exparg.lastp = &exparg.list; 175 if (full) { 176 ifsbreakup(p, &exparg); 177 *exparg.lastp = NULL; 178 exparg.lastp = &exparg.list; 179 expandmeta(exparg.list); 180 } else { 181 sp = (struct strlist *)stalloc(sizeof (struct strlist)); 182 sp->text = p; 183 *exparg.lastp = sp; 184 exparg.lastp = &sp->next; 185 } 186 while (ifsfirst.next != NULL) { 187 struct ifsregion *ifsp; 188 INTOFF; 189 ifsp = ifsfirst.next->next; 190 ckfree(ifsfirst.next); 191 ifsfirst.next = ifsp; 192 INTON; 193 } 194 *exparg.lastp = NULL; 195 if (exparg.list) { 196 *arglist->lastp = exparg.list; 197 arglist->lastp = exparg.lastp; 198 } 199 } 200 201 202 203 /* 204 * Perform variable and command substitution. If full is set, output CTLESC 205 * characters to allow for further processing. If full is not set, treat 206 * $@ like $* since no splitting will be performed. 207 */ 208 209 STATIC void 210 argstr(p, full) 211 register char *p; 212 { 213 char c; 214 215 for (;;) { 216 switch (c = *p++) { 217 case '\0': 218 case CTLENDVAR: 219 goto breakloop; 220 case CTLESC: 221 if (full) 222 STPUTC(c, expdest); 223 c = *p++; 224 STPUTC(c, expdest); 225 break; 226 case CTLVAR: 227 p = evalvar(p, full); 228 break; 229 case CTLBACKQ: 230 case CTLBACKQ|CTLQUOTE: 231 expbackq(argbackq->n, c & CTLQUOTE, full); 232 argbackq = argbackq->next; 233 break; 234 default: 235 STPUTC(c, expdest); 236 } 237 } 238 breakloop:; 239 } 240 241 242 /* 243 * Expand stuff in backwards quotes. 244 */ 245 246 STATIC void 247 expbackq(cmd, quoted, full) 248 union node *cmd; 249 { 250 struct backcmd in; 251 int i; 252 char buf[128]; 253 char *p; 254 char *dest = expdest; 255 struct ifsregion saveifs, *savelastp; 256 struct nodelist *saveargbackq; 257 char lastc; 258 int startloc = dest - stackblock(); 259 char const *syntax = quoted? DQSYNTAX : BASESYNTAX; 260 int saveherefd; 261 262 INTOFF; 263 saveifs = ifsfirst; 264 savelastp = ifslastp; 265 saveargbackq = argbackq; 266 saveherefd = herefd; 267 herefd = -1; 268 p = grabstackstr(dest); 269 evalbackcmd(cmd, &in); 270 ungrabstackstr(p, dest); 271 ifsfirst = saveifs; 272 ifslastp = savelastp; 273 argbackq = saveargbackq; 274 herefd = saveherefd; 275 276 p = in.buf; 277 lastc = '\0'; 278 for (;;) { 279 if (--in.nleft < 0) { 280 if (in.fd < 0) 281 break; 282 while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR); 283 TRACE(("expbackq: read returns %d\n", i)); 284 if (i <= 0) 285 break; 286 p = buf; 287 in.nleft = i - 1; 288 } 289 lastc = *p++; 290 if (lastc != '\0') { 291 if (full && syntax[lastc] == CCTL) 292 STPUTC(CTLESC, dest); 293 STPUTC(lastc, dest); 294 } 295 } 296 if (lastc == '\n') { 297 STUNPUTC(dest); 298 } 299 if (in.fd >= 0) 300 close(in.fd); 301 if (in.buf) 302 ckfree(in.buf); 303 if (in.jp) 304 exitstatus = waitforjob(in.jp); 305 if (quoted == 0) 306 recordregion(startloc, dest - stackblock(), 0); 307 TRACE(("evalbackq: size=%d: \"%.*s\"\n", 308 (dest - stackblock()) - startloc, 309 (dest - stackblock()) - startloc, 310 stackblock() + startloc)); 311 expdest = dest; 312 INTON; 313 } 314 315 316 317 /* 318 * Expand a variable, and return a pointer to the next character in the 319 * input string. 320 */ 321 322 STATIC char * 323 evalvar(p, full) 324 char *p; 325 { 326 int subtype; 327 int flags; 328 char *var; 329 char *val; 330 int c; 331 int set; 332 int special; 333 int startloc; 334 335 flags = *p++; 336 subtype = flags & VSTYPE; 337 var = p; 338 special = 0; 339 if (! is_name(*p)) 340 special = 1; 341 p = strchr(p, '=') + 1; 342 again: /* jump here after setting a variable with ${var=text} */ 343 if (special) { 344 set = varisset(*var); 345 val = NULL; 346 } else { 347 val = lookupvar(var); 348 if (val == NULL || (flags & VSNUL) && val[0] == '\0') { 349 val = NULL; 350 set = 0; 351 } else 352 set = 1; 353 } 354 startloc = expdest - stackblock(); 355 if (set && subtype != VSPLUS) { 356 /* insert the value of the variable */ 357 if (special) { 358 varvalue(*var, flags & VSQUOTE, full); 359 } else { 360 char const *syntax = (flags & VSQUOTE)? DQSYNTAX : BASESYNTAX; 361 362 while (*val) { 363 if (full && syntax[*val] == CCTL) 364 STPUTC(CTLESC, expdest); 365 STPUTC(*val++, expdest); 366 } 367 } 368 } 369 if (subtype == VSPLUS) 370 set = ! set; 371 if (((flags & VSQUOTE) == 0 || (*var == '@' && shellparam.nparam != 1)) 372 && (set || subtype == VSNORMAL)) 373 recordregion(startloc, expdest - stackblock(), flags & VSQUOTE); 374 if (! set && subtype != VSNORMAL) { 375 if (subtype == VSPLUS || subtype == VSMINUS) { 376 argstr(p, full); 377 } else { 378 char *startp; 379 int saveherefd = herefd; 380 struct nodelist *saveargbackq = argbackq; 381 herefd = -1; 382 argstr(p, 0); 383 STACKSTRNUL(expdest); 384 herefd = saveherefd; 385 argbackq = saveargbackq; 386 startp = stackblock() + startloc; 387 if (subtype == VSASSIGN) { 388 setvar(var, startp, 0); 389 STADJUST(startp - expdest, expdest); 390 flags &=~ VSNUL; 391 goto again; 392 } 393 /* subtype == VSQUESTION */ 394 if (*p != CTLENDVAR) { 395 outfmt(&errout, "%s\n", startp); 396 error((char *)NULL); 397 } 398 error("%.*s: parameter %snot set", p - var - 1, 399 var, (flags & VSNUL)? "null or " : nullstr); 400 } 401 } 402 if (subtype != VSNORMAL) { /* skip to end of alternative */ 403 int nesting = 1; 404 for (;;) { 405 if ((c = *p++) == CTLESC) 406 p++; 407 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { 408 if (set) 409 argbackq = argbackq->next; 410 } else if (c == CTLVAR) { 411 if ((*p++ & VSTYPE) != VSNORMAL) 412 nesting++; 413 } else if (c == CTLENDVAR) { 414 if (--nesting == 0) 415 break; 416 } 417 } 418 } 419 return p; 420 } 421 422 423 424 /* 425 * Test whether a specialized variable is set. 426 */ 427 428 STATIC int 429 varisset(name) 430 char name; 431 { 432 char **ap; 433 434 if (name == '!') { 435 if (backgndpid == -1) 436 return 0; 437 } else if (name == '@' || name == '*') { 438 if (*shellparam.p == NULL) 439 return 0; 440 } else if ((unsigned)(name -= '1') <= '9' - '1') { 441 ap = shellparam.p; 442 do { 443 if (*ap++ == NULL) 444 return 0; 445 } while (--name >= 0); 446 } 447 return 1; 448 } 449 450 451 452 /* 453 * Add the value of a specialized variable to the stack string. 454 */ 455 456 STATIC void 457 varvalue(name, quoted, allow_split) 458 char name; 459 { 460 int num; 461 char temp[32]; 462 char *p; 463 int i; 464 extern int exitstatus; 465 char sep; 466 char **ap; 467 char const *syntax; 468 469 switch (name) { 470 case '$': 471 num = rootpid; 472 goto numvar; 473 case '?': 474 num = exitstatus; 475 goto numvar; 476 case '#': 477 num = shellparam.nparam; 478 goto numvar; 479 case '!': 480 num = backgndpid; 481 numvar: 482 p = temp + 31; 483 temp[31] = '\0'; 484 do { 485 *--p = num % 10 + '0'; 486 } while ((num /= 10) != 0); 487 while (*p) 488 STPUTC(*p++, expdest); 489 break; 490 case '-': 491 for (i = 0 ; optchar[i] ; i++) { 492 if (optval[i]) 493 STPUTC(optchar[i], expdest); 494 } 495 break; 496 case '@': 497 if (allow_split) { 498 sep = '\0'; 499 goto allargs; 500 } 501 /* fall through */ 502 case '*': 503 sep = ' '; 504 allargs: 505 /* Only emit CTLESC if we will do further processing, 506 i.e. if allow_split is set. */ 507 syntax = quoted && allow_split ? DQSYNTAX : BASESYNTAX; 508 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 509 /* should insert CTLESC characters */ 510 while (*p) { 511 if (syntax[*p] == CCTL) 512 STPUTC(CTLESC, expdest); 513 STPUTC(*p++, expdest); 514 } 515 if (*ap) 516 STPUTC(sep, expdest); 517 } 518 break; 519 case '0': 520 p = arg0; 521 string: 522 /* Only emit CTLESC if we will do further processing, 523 i.e. if allow_split is set. */ 524 syntax = quoted && allow_split ? DQSYNTAX : BASESYNTAX; 525 while (*p) { 526 if (syntax[*p] == CCTL) 527 STPUTC(CTLESC, expdest); 528 STPUTC(*p++, expdest); 529 } 530 break; 531 default: 532 if ((unsigned)(name -= '1') <= '9' - '1') { 533 p = shellparam.p[name]; 534 goto string; 535 } 536 break; 537 } 538 } 539 540 541 542 /* 543 * Record the the fact that we have to scan this region of the 544 * string for IFS characters. 545 */ 546 547 STATIC void 548 recordregion(start, end, nulonly) { 549 register struct ifsregion *ifsp; 550 551 if (ifslastp == NULL) { 552 ifsp = &ifsfirst; 553 } else { 554 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 555 ifslastp->next = ifsp; 556 } 557 ifslastp = ifsp; 558 ifslastp->next = NULL; 559 ifslastp->begoff = start; 560 ifslastp->endoff = end; 561 ifslastp->nulonly = nulonly; 562 } 563 564 565 566 /* 567 * Break the argument string into pieces based upon IFS and add the 568 * strings to the argument list. The regions of the string to be 569 * searched for IFS characters have been stored by recordregion. 570 */ 571 572 STATIC void 573 ifsbreakup(string, arglist) 574 char *string; 575 struct arglist *arglist; 576 { 577 struct ifsregion *ifsp; 578 struct strlist *sp; 579 char *start; 580 register char *p; 581 char *q; 582 char *ifs; 583 584 start = string; 585 if (ifslastp != NULL) { 586 ifsp = &ifsfirst; 587 do { 588 p = string + ifsp->begoff; 589 ifs = ifsp->nulonly? nullstr : ifsval(); 590 while (p < string + ifsp->endoff) { 591 q = p; 592 if (*p == CTLESC) 593 p++; 594 if (strchr(ifs, *p++)) { 595 if (q > start || *ifs != ' ') { 596 *q = '\0'; 597 sp = (struct strlist *)stalloc(sizeof *sp); 598 sp->text = start; 599 *arglist->lastp = sp; 600 arglist->lastp = &sp->next; 601 } 602 if (*ifs == ' ') { 603 for (;;) { 604 if (p >= string + ifsp->endoff) 605 break; 606 q = p; 607 if (*p == CTLESC) 608 p++; 609 if (strchr(ifs, *p++) == NULL) { 610 p = q; 611 break; 612 } 613 } 614 } 615 start = p; 616 } 617 } 618 } while ((ifsp = ifsp->next) != NULL); 619 if (*start || (*ifs != ' ' && start > string)) { 620 sp = (struct strlist *)stalloc(sizeof *sp); 621 sp->text = start; 622 *arglist->lastp = sp; 623 arglist->lastp = &sp->next; 624 } 625 } else { 626 sp = (struct strlist *)stalloc(sizeof *sp); 627 sp->text = start; 628 *arglist->lastp = sp; 629 arglist->lastp = &sp->next; 630 } 631 } 632 633 634 635 /* 636 * Expand shell metacharacters. At this point, the only control characters 637 * should be escapes. The results are stored in the list exparg. 638 */ 639 640 char *expdir; 641 642 643 STATIC void 644 expandmeta(str) 645 struct strlist *str; 646 { 647 char *p; 648 struct strlist **savelastp; 649 struct strlist *sp; 650 char c; 651 652 while (str) { 653 if (fflag) 654 goto nometa; 655 p = str->text; 656 #if UDIR 657 if (p[0] == '/' && p[1] == 'u' && p[2] == '/') 658 str->text = p = expudir(p); 659 #endif 660 for (;;) { /* fast check for meta chars */ 661 if ((c = *p++) == '\0') 662 goto nometa; 663 if (c == '*' || c == '?' || c == '[' || c == '!') 664 break; 665 } 666 savelastp = exparg.lastp; 667 INTOFF; 668 if (expdir == NULL) 669 expdir = ckmalloc(1024); /* I hope this is big enough */ 670 expmeta(expdir, str->text); 671 ckfree(expdir); 672 expdir = NULL; 673 INTON; 674 if (exparg.lastp == savelastp) { 675 if (! zflag) { 676 nometa: 677 *exparg.lastp = str; 678 rmescapes(str->text); 679 exparg.lastp = &str->next; 680 } 681 } else { 682 *exparg.lastp = NULL; 683 *savelastp = sp = expsort(*savelastp); 684 while (sp->next != NULL) 685 sp = sp->next; 686 exparg.lastp = &sp->next; 687 } 688 str = str->next; 689 } 690 } 691 692 693 #if UDIR 694 /* 695 * Expand /u/username into the home directory for the specified user. 696 * We could use the getpw stuff here, but then we would have to load 697 * in stdio and who knows what else. 698 */ 699 700 #define MAXLOGNAME 32 701 #define MAXPWLINE 128 702 703 char *pfgets(); 704 705 706 STATIC char * 707 expudir(path) 708 char *path; 709 { 710 register char *p, *q, *r; 711 char name[MAXLOGNAME]; 712 char line[MAXPWLINE]; 713 int i; 714 715 r = path; /* result on failure */ 716 p = r + 3; /* the 3 skips "/u/" */ 717 q = name; 718 while (*p && *p != '/') { 719 if (q >= name + MAXLOGNAME - 1) 720 return r; /* fail, name too long */ 721 *q++ = *p++; 722 } 723 *q = '\0'; 724 setinputfile("/etc/passwd", 1); 725 q = line + strlen(name); 726 while (pfgets(line, MAXPWLINE) != NULL) { 727 if (line[0] == name[0] && prefix(name, line) && *q == ':') { 728 /* skip to start of home directory */ 729 i = 4; 730 do { 731 while (*++q && *q != ':'); 732 } while (--i > 0); 733 if (*q == '\0') 734 break; /* fail, corrupted /etc/passwd */ 735 q++; 736 for (r = q ; *r && *r != '\n' && *r != ':' ; r++); 737 *r = '\0'; /* nul terminate home directory */ 738 i = r - q; /* i = strlen(q) */ 739 r = stalloc(i + strlen(p) + 1); 740 scopy(q, r); 741 scopy(p, r + i); 742 TRACE(("expudir converts %s to %s\n", path, r)); 743 didudir = 1; 744 path = r; /* succeed */ 745 break; 746 } 747 } 748 popfile(); 749 return r; 750 } 751 #endif 752 753 754 /* 755 * Do metacharacter (i.e. *, ?, [...]) expansion. 756 */ 757 758 STATIC void 759 expmeta(enddir, name) 760 char *enddir; 761 char *name; 762 { 763 register char *p; 764 char *q; 765 char *start; 766 char *endname; 767 int metaflag; 768 struct stat statb; 769 DIR *dirp; 770 struct dirent *dp; 771 int atend; 772 int matchdot; 773 774 metaflag = 0; 775 start = name; 776 for (p = name ; ; p++) { 777 if (*p == '*' || *p == '?') 778 metaflag = 1; 779 else if (*p == '[') { 780 q = p + 1; 781 if (*q == '!') 782 q++; 783 for (;;) { 784 if (*q == CTLESC) 785 q++; 786 if (*q == '/' || *q == '\0') 787 break; 788 if (*++q == ']') { 789 metaflag = 1; 790 break; 791 } 792 } 793 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 794 metaflag = 1; 795 } else if (*p == '\0') 796 break; 797 else if (*p == CTLESC) 798 p++; 799 if (*p == '/') { 800 if (metaflag) 801 break; 802 start = p + 1; 803 } 804 } 805 if (metaflag == 0) { /* we've reached the end of the file name */ 806 if (enddir != expdir) 807 metaflag++; 808 for (p = name ; ; p++) { 809 if (*p == CTLESC) 810 p++; 811 *enddir++ = *p; 812 if (*p == '\0') 813 break; 814 } 815 if (metaflag == 0 || stat(expdir, &statb) >= 0) 816 addfname(expdir); 817 return; 818 } 819 endname = p; 820 if (start != name) { 821 p = name; 822 while (p < start) { 823 if (*p == CTLESC) 824 p++; 825 *enddir++ = *p++; 826 } 827 } 828 if (enddir == expdir) { 829 p = "."; 830 } else if (enddir == expdir + 1 && *expdir == '/') { 831 p = "/"; 832 } else { 833 p = expdir; 834 enddir[-1] = '\0'; 835 } 836 if ((dirp = opendir(p)) == NULL) 837 return; 838 if (enddir != expdir) 839 enddir[-1] = '/'; 840 if (*endname == 0) { 841 atend = 1; 842 } else { 843 atend = 0; 844 *endname++ = '\0'; 845 } 846 matchdot = 0; 847 if (start[0] == '.' || start[0] == CTLESC && start[1] == '.') 848 matchdot++; 849 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 850 if (dp->d_name[0] == '.' && ! matchdot) 851 continue; 852 if (patmatch(start, dp->d_name)) { 853 if (atend) { 854 scopy(dp->d_name, enddir); 855 addfname(expdir); 856 } else { 857 char *q; 858 for (p = enddir, q = dp->d_name ; *p++ = *q++ ;); 859 p[-1] = '/'; 860 expmeta(p, endname); 861 } 862 } 863 } 864 closedir(dirp); 865 if (! atend) 866 endname[-1] = '/'; 867 } 868 869 870 /* 871 * Add a file name to the list. 872 */ 873 874 STATIC void 875 addfname(name) 876 char *name; 877 { 878 char *p; 879 struct strlist *sp; 880 881 p = stalloc(strlen(name) + 1); 882 scopy(name, p); 883 sp = (struct strlist *)stalloc(sizeof *sp); 884 sp->text = p; 885 *exparg.lastp = sp; 886 exparg.lastp = &sp->next; 887 } 888 889 890 /* 891 * Sort the results of file name expansion. It calculates the number of 892 * strings to sort and then calls msort (short for merge sort) to do the 893 * work. 894 */ 895 896 STATIC struct strlist * 897 expsort(str) 898 struct strlist *str; 899 { 900 int len; 901 struct strlist *sp; 902 903 len = 0; 904 for (sp = str ; sp ; sp = sp->next) 905 len++; 906 return msort(str, len); 907 } 908 909 910 STATIC struct strlist * 911 msort(list, len) 912 struct strlist *list; 913 { 914 struct strlist *p, *q; 915 struct strlist **lpp; 916 int half; 917 int n; 918 919 if (len <= 1) 920 return list; 921 half = len >> 1; 922 p = list; 923 for (n = half ; --n >= 0 ; ) { 924 q = p; 925 p = p->next; 926 } 927 q->next = NULL; /* terminate first half of list */ 928 q = msort(list, half); /* sort first half of list */ 929 p = msort(p, len - half); /* sort second half */ 930 lpp = &list; 931 for (;;) { 932 if (strcmp(p->text, q->text) < 0) { 933 *lpp = p; 934 lpp = &p->next; 935 if ((p = *lpp) == NULL) { 936 *lpp = q; 937 break; 938 } 939 } else { 940 *lpp = q; 941 lpp = &q->next; 942 if ((q = *lpp) == NULL) { 943 *lpp = p; 944 break; 945 } 946 } 947 } 948 return list; 949 } 950 951 952 953 /* 954 * Returns true if the pattern matches the string. 955 */ 956 957 int 958 patmatch(pattern, string) 959 char *pattern; 960 char *string; 961 { 962 if (pattern[0] == '!' && pattern[1] == '!') 963 return 1 - pmatch(pattern + 2, string); 964 else 965 return pmatch(pattern, string); 966 } 967 968 969 STATIC int 970 pmatch(pattern, string) 971 char *pattern; 972 char *string; 973 { 974 register char *p, *q; 975 register char c; 976 977 p = pattern; 978 q = string; 979 for (;;) { 980 switch (c = *p++) { 981 case '\0': 982 goto breakloop; 983 case CTLESC: 984 if (*q++ != *p++) 985 return 0; 986 break; 987 case '?': 988 if (*q++ == '\0') 989 return 0; 990 break; 991 case '*': 992 c = *p; 993 if (c != CTLESC && c != '?' && c != '*' && c != '[') { 994 while (*q != c) { 995 if (*q == '\0') 996 return 0; 997 q++; 998 } 999 } 1000 do { 1001 if (pmatch(p, q)) 1002 return 1; 1003 } while (*q++ != '\0'); 1004 return 0; 1005 case '[': { 1006 char *endp; 1007 int invert, found; 1008 char chr; 1009 1010 endp = p; 1011 if (*endp == '!') 1012 endp++; 1013 for (;;) { 1014 if (*endp == '\0') 1015 goto dft; /* no matching ] */ 1016 if (*endp == CTLESC) 1017 endp++; 1018 if (*++endp == ']') 1019 break; 1020 } 1021 invert = 0; 1022 if (*p == '!') { 1023 invert++; 1024 p++; 1025 } 1026 found = 0; 1027 chr = *q++; 1028 c = *p++; 1029 do { 1030 if (c == CTLESC) 1031 c = *p++; 1032 if (*p == '-' && p[1] != ']') { 1033 p++; 1034 if (*p == CTLESC) 1035 p++; 1036 if (chr >= c && chr <= *p) 1037 found = 1; 1038 p++; 1039 } else { 1040 if (chr == c) 1041 found = 1; 1042 } 1043 } while ((c = *p++) != ']'); 1044 if (found == invert) 1045 return 0; 1046 break; 1047 } 1048 dft: default: 1049 if (*q++ != c) 1050 return 0; 1051 break; 1052 } 1053 } 1054 breakloop: 1055 if (*q != '\0') 1056 return 0; 1057 return 1; 1058 } 1059 1060 1061 1062 /* 1063 * Remove any CTLESC characters from a string. 1064 */ 1065 1066 void 1067 rmescapes(str) 1068 char *str; 1069 { 1070 register char *p, *q; 1071 1072 p = str; 1073 while (*p != CTLESC) { 1074 if (*p++ == '\0') 1075 return; 1076 } 1077 q = p; 1078 while (*p) { 1079 if (*p == CTLESC) 1080 p++; 1081 *q++ = *p++; 1082 } 1083 *q = '\0'; 1084 } 1085 1086 1087 1088 /* 1089 * See if a pattern matches in a case statement. 1090 */ 1091 1092 int 1093 casematch(pattern, val) 1094 union node *pattern; 1095 char *val; 1096 { 1097 struct stackmark smark; 1098 int result; 1099 char *p; 1100 1101 setstackmark(&smark); 1102 argbackq = pattern->narg.backquote; 1103 STARTSTACKSTR(expdest); 1104 ifslastp = NULL; 1105 /* Preserve any CTLESC characters inserted previously, so that 1106 we won't expand reg exps which are inside strings. */ 1107 argstr(pattern->narg.text, 1); 1108 STPUTC('\0', expdest); 1109 p = grabstackstr(expdest); 1110 result = patmatch(p, val); 1111 popstackmark(&smark); 1112 return result; 1113 } 1114