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[] = "@(#)expand.c 5.1 (Berkeley) 3/7/91"; 39 static char rcsid[] = "$Header: /cvsroot/src/bin/sh/expand.c,v 1.3 1993/03/23 00:28:00 cgd 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 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 herefd = -1; 381 argstr(p, 0); 382 STACKSTRNUL(expdest); 383 herefd = saveherefd; 384 startp = stackblock() + startloc; 385 if (subtype == VSASSIGN) { 386 setvar(var, startp, 0); 387 STADJUST(startp - expdest, expdest); 388 flags &=~ VSNUL; 389 goto again; 390 } 391 /* subtype == VSQUESTION */ 392 if (*p != CTLENDVAR) { 393 outfmt(&errout, "%s\n", startp); 394 error((char *)NULL); 395 } 396 error("%.*s: parameter %snot set", p - var - 1, 397 var, (flags & VSNUL)? "null or " : nullstr); 398 } 399 } 400 if (subtype != VSNORMAL) { /* skip to end of alternative */ 401 int nesting = 1; 402 for (;;) { 403 if ((c = *p++) == CTLESC) 404 p++; 405 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { 406 if (set) 407 argbackq = argbackq->next; 408 } else if (c == CTLVAR) { 409 if ((*p++ & VSTYPE) != VSNORMAL) 410 nesting++; 411 } else if (c == CTLENDVAR) { 412 if (--nesting == 0) 413 break; 414 } 415 } 416 } 417 return p; 418 } 419 420 421 422 /* 423 * Test whether a specialized variable is set. 424 */ 425 426 STATIC int 427 varisset(name) 428 char name; 429 { 430 char **ap; 431 432 if (name == '!') { 433 if (backgndpid == -1) 434 return 0; 435 } else if (name == '@' || name == '*') { 436 if (*shellparam.p == NULL) 437 return 0; 438 } else if ((unsigned)(name -= '1') <= '9' - '1') { 439 ap = shellparam.p; 440 do { 441 if (*ap++ == NULL) 442 return 0; 443 } while (--name >= 0); 444 } 445 return 1; 446 } 447 448 449 450 /* 451 * Add the value of a specialized variable to the stack string. 452 */ 453 454 STATIC void 455 varvalue(name, quoted, allow_split) 456 char name; 457 { 458 int num; 459 char temp[32]; 460 char *p; 461 int i; 462 extern int exitstatus; 463 char sep; 464 char **ap; 465 char const *syntax; 466 467 switch (name) { 468 case '$': 469 num = rootpid; 470 goto numvar; 471 case '?': 472 num = exitstatus; 473 goto numvar; 474 case '#': 475 num = shellparam.nparam; 476 goto numvar; 477 case '!': 478 num = backgndpid; 479 numvar: 480 p = temp + 31; 481 temp[31] = '\0'; 482 do { 483 *--p = num % 10 + '0'; 484 } while ((num /= 10) != 0); 485 while (*p) 486 STPUTC(*p++, expdest); 487 break; 488 case '-': 489 for (i = 0 ; optchar[i] ; i++) { 490 if (optval[i]) 491 STPUTC(optchar[i], expdest); 492 } 493 break; 494 case '@': 495 if (allow_split) { 496 sep = '\0'; 497 goto allargs; 498 } 499 /* fall through */ 500 case '*': 501 sep = ' '; 502 allargs: 503 syntax = quoted? DQSYNTAX : BASESYNTAX; 504 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 505 /* should insert CTLESC characters */ 506 while (*p) { 507 if (syntax[*p] == CCTL) 508 STPUTC(CTLESC, expdest); 509 STPUTC(*p++, expdest); 510 } 511 if (*ap) 512 STPUTC(sep, expdest); 513 } 514 break; 515 case '0': 516 p = arg0; 517 string: 518 syntax = quoted? DQSYNTAX : BASESYNTAX; 519 while (*p) { 520 if (syntax[*p] == CCTL) 521 STPUTC(CTLESC, expdest); 522 STPUTC(*p++, expdest); 523 } 524 break; 525 default: 526 if ((unsigned)(name -= '1') <= '9' - '1') { 527 p = shellparam.p[name]; 528 goto string; 529 } 530 break; 531 } 532 } 533 534 535 536 /* 537 * Record the the fact that we have to scan this region of the 538 * string for IFS characters. 539 */ 540 541 STATIC void 542 recordregion(start, end, nulonly) { 543 register struct ifsregion *ifsp; 544 545 if (ifslastp == NULL) { 546 ifsp = &ifsfirst; 547 } else { 548 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 549 ifslastp->next = ifsp; 550 } 551 ifslastp = ifsp; 552 ifslastp->next = NULL; 553 ifslastp->begoff = start; 554 ifslastp->endoff = end; 555 ifslastp->nulonly = nulonly; 556 } 557 558 559 560 /* 561 * Break the argument string into pieces based upon IFS and add the 562 * strings to the argument list. The regions of the string to be 563 * searched for IFS characters have been stored by recordregion. 564 */ 565 566 STATIC void 567 ifsbreakup(string, arglist) 568 char *string; 569 struct arglist *arglist; 570 { 571 struct ifsregion *ifsp; 572 struct strlist *sp; 573 char *start; 574 register char *p; 575 char *q; 576 char *ifs; 577 578 start = string; 579 if (ifslastp != NULL) { 580 ifsp = &ifsfirst; 581 do { 582 p = string + ifsp->begoff; 583 ifs = ifsp->nulonly? nullstr : ifsval(); 584 while (p < string + ifsp->endoff) { 585 q = p; 586 if (*p == CTLESC) 587 p++; 588 if (strchr(ifs, *p++)) { 589 if (q > start || *ifs != ' ') { 590 *q = '\0'; 591 sp = (struct strlist *)stalloc(sizeof *sp); 592 sp->text = start; 593 *arglist->lastp = sp; 594 arglist->lastp = &sp->next; 595 } 596 if (*ifs == ' ') { 597 for (;;) { 598 if (p >= string + ifsp->endoff) 599 break; 600 q = p; 601 if (*p == CTLESC) 602 p++; 603 if (strchr(ifs, *p++) == NULL) { 604 p = q; 605 break; 606 } 607 } 608 } 609 start = p; 610 } 611 } 612 } while ((ifsp = ifsp->next) != NULL); 613 if (*start || (*ifs != ' ' && start > string)) { 614 sp = (struct strlist *)stalloc(sizeof *sp); 615 sp->text = start; 616 *arglist->lastp = sp; 617 arglist->lastp = &sp->next; 618 } 619 } else { 620 sp = (struct strlist *)stalloc(sizeof *sp); 621 sp->text = start; 622 *arglist->lastp = sp; 623 arglist->lastp = &sp->next; 624 } 625 } 626 627 628 629 /* 630 * Expand shell metacharacters. At this point, the only control characters 631 * should be escapes. The results are stored in the list exparg. 632 */ 633 634 char *expdir; 635 636 637 STATIC void 638 expandmeta(str) 639 struct strlist *str; 640 { 641 char *p; 642 struct strlist **savelastp; 643 struct strlist *sp; 644 char c; 645 646 while (str) { 647 if (fflag) 648 goto nometa; 649 p = str->text; 650 #if UDIR 651 if (p[0] == '/' && p[1] == 'u' && p[2] == '/') 652 str->text = p = expudir(p); 653 #endif 654 for (;;) { /* fast check for meta chars */ 655 if ((c = *p++) == '\0') 656 goto nometa; 657 if (c == '*' || c == '?' || c == '[' || c == '!') 658 break; 659 } 660 savelastp = exparg.lastp; 661 INTOFF; 662 if (expdir == NULL) 663 expdir = ckmalloc(1024); /* I hope this is big enough */ 664 expmeta(expdir, str->text); 665 ckfree(expdir); 666 expdir = NULL; 667 INTON; 668 if (exparg.lastp == savelastp) { 669 if (! zflag) { 670 nometa: 671 *exparg.lastp = str; 672 rmescapes(str->text); 673 exparg.lastp = &str->next; 674 } 675 } else { 676 *exparg.lastp = NULL; 677 *savelastp = sp = expsort(*savelastp); 678 while (sp->next != NULL) 679 sp = sp->next; 680 exparg.lastp = &sp->next; 681 } 682 str = str->next; 683 } 684 } 685 686 687 #if UDIR 688 /* 689 * Expand /u/username into the home directory for the specified user. 690 * We could use the getpw stuff here, but then we would have to load 691 * in stdio and who knows what else. 692 */ 693 694 #define MAXLOGNAME 32 695 #define MAXPWLINE 128 696 697 char *pfgets(); 698 699 700 STATIC char * 701 expudir(path) 702 char *path; 703 { 704 register char *p, *q, *r; 705 char name[MAXLOGNAME]; 706 char line[MAXPWLINE]; 707 int i; 708 709 r = path; /* result on failure */ 710 p = r + 3; /* the 3 skips "/u/" */ 711 q = name; 712 while (*p && *p != '/') { 713 if (q >= name + MAXLOGNAME - 1) 714 return r; /* fail, name too long */ 715 *q++ = *p++; 716 } 717 *q = '\0'; 718 setinputfile("/etc/passwd", 1); 719 q = line + strlen(name); 720 while (pfgets(line, MAXPWLINE) != NULL) { 721 if (line[0] == name[0] && prefix(name, line) && *q == ':') { 722 /* skip to start of home directory */ 723 i = 4; 724 do { 725 while (*++q && *q != ':'); 726 } while (--i > 0); 727 if (*q == '\0') 728 break; /* fail, corrupted /etc/passwd */ 729 q++; 730 for (r = q ; *r && *r != '\n' && *r != ':' ; r++); 731 *r = '\0'; /* nul terminate home directory */ 732 i = r - q; /* i = strlen(q) */ 733 r = stalloc(i + strlen(p) + 1); 734 scopy(q, r); 735 scopy(p, r + i); 736 TRACE(("expudir converts %s to %s\n", path, r)); 737 didudir = 1; 738 path = r; /* succeed */ 739 break; 740 } 741 } 742 popfile(); 743 return r; 744 } 745 #endif 746 747 748 /* 749 * Do metacharacter (i.e. *, ?, [...]) expansion. 750 */ 751 752 STATIC void 753 expmeta(enddir, name) 754 char *enddir; 755 char *name; 756 { 757 register char *p; 758 char *q; 759 char *start; 760 char *endname; 761 int metaflag; 762 struct stat statb; 763 DIR *dirp; 764 struct dirent *dp; 765 int atend; 766 int matchdot; 767 768 metaflag = 0; 769 start = name; 770 for (p = name ; ; p++) { 771 if (*p == '*' || *p == '?') 772 metaflag = 1; 773 else if (*p == '[') { 774 q = p + 1; 775 if (*q == '!') 776 q++; 777 for (;;) { 778 if (*q == CTLESC) 779 q++; 780 if (*q == '/' || *q == '\0') 781 break; 782 if (*++q == ']') { 783 metaflag = 1; 784 break; 785 } 786 } 787 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 788 metaflag = 1; 789 } else if (*p == '\0') 790 break; 791 else if (*p == CTLESC) 792 p++; 793 if (*p == '/') { 794 if (metaflag) 795 break; 796 start = p + 1; 797 } 798 } 799 if (metaflag == 0) { /* we've reached the end of the file name */ 800 if (enddir != expdir) 801 metaflag++; 802 for (p = name ; ; p++) { 803 if (*p == CTLESC) 804 p++; 805 *enddir++ = *p; 806 if (*p == '\0') 807 break; 808 } 809 if (metaflag == 0 || stat(expdir, &statb) >= 0) 810 addfname(expdir); 811 return; 812 } 813 endname = p; 814 if (start != name) { 815 p = name; 816 while (p < start) { 817 if (*p == CTLESC) 818 p++; 819 *enddir++ = *p++; 820 } 821 } 822 if (enddir == expdir) { 823 p = "."; 824 } else if (enddir == expdir + 1 && *expdir == '/') { 825 p = "/"; 826 } else { 827 p = expdir; 828 enddir[-1] = '\0'; 829 } 830 if ((dirp = opendir(p)) == NULL) 831 return; 832 if (enddir != expdir) 833 enddir[-1] = '/'; 834 if (*endname == 0) { 835 atend = 1; 836 } else { 837 atend = 0; 838 *endname++ = '\0'; 839 } 840 matchdot = 0; 841 if (start[0] == '.' || start[0] == CTLESC && start[1] == '.') 842 matchdot++; 843 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 844 if (dp->d_name[0] == '.' && ! matchdot) 845 continue; 846 if (patmatch(start, dp->d_name)) { 847 if (atend) { 848 scopy(dp->d_name, enddir); 849 addfname(expdir); 850 } else { 851 char *q; 852 for (p = enddir, q = dp->d_name ; *p++ = *q++ ;); 853 p[-1] = '/'; 854 expmeta(p, endname); 855 } 856 } 857 } 858 closedir(dirp); 859 if (! atend) 860 endname[-1] = '/'; 861 } 862 863 864 /* 865 * Add a file name to the list. 866 */ 867 868 STATIC void 869 addfname(name) 870 char *name; 871 { 872 char *p; 873 struct strlist *sp; 874 875 p = stalloc(strlen(name) + 1); 876 scopy(name, p); 877 sp = (struct strlist *)stalloc(sizeof *sp); 878 sp->text = p; 879 *exparg.lastp = sp; 880 exparg.lastp = &sp->next; 881 } 882 883 884 /* 885 * Sort the results of file name expansion. It calculates the number of 886 * strings to sort and then calls msort (short for merge sort) to do the 887 * work. 888 */ 889 890 STATIC struct strlist * 891 expsort(str) 892 struct strlist *str; 893 { 894 int len; 895 struct strlist *sp; 896 897 len = 0; 898 for (sp = str ; sp ; sp = sp->next) 899 len++; 900 return msort(str, len); 901 } 902 903 904 STATIC struct strlist * 905 msort(list, len) 906 struct strlist *list; 907 { 908 struct strlist *p, *q; 909 struct strlist **lpp; 910 int half; 911 int n; 912 913 if (len <= 1) 914 return list; 915 half = len >> 1; 916 p = list; 917 for (n = half ; --n >= 0 ; ) { 918 q = p; 919 p = p->next; 920 } 921 q->next = NULL; /* terminate first half of list */ 922 q = msort(list, half); /* sort first half of list */ 923 p = msort(p, len - half); /* sort second half */ 924 lpp = &list; 925 for (;;) { 926 if (strcmp(p->text, q->text) < 0) { 927 *lpp = p; 928 lpp = &p->next; 929 if ((p = *lpp) == NULL) { 930 *lpp = q; 931 break; 932 } 933 } else { 934 *lpp = q; 935 lpp = &q->next; 936 if ((q = *lpp) == NULL) { 937 *lpp = p; 938 break; 939 } 940 } 941 } 942 return list; 943 } 944 945 946 947 /* 948 * Returns true if the pattern matches the string. 949 */ 950 951 int 952 patmatch(pattern, string) 953 char *pattern; 954 char *string; 955 { 956 if (pattern[0] == '!' && pattern[1] == '!') 957 return 1 - pmatch(pattern + 2, string); 958 else 959 return pmatch(pattern, string); 960 } 961 962 963 STATIC int 964 pmatch(pattern, string) 965 char *pattern; 966 char *string; 967 { 968 register char *p, *q; 969 register char c; 970 971 p = pattern; 972 q = string; 973 for (;;) { 974 switch (c = *p++) { 975 case '\0': 976 goto breakloop; 977 case CTLESC: 978 if (*q++ != *p++) 979 return 0; 980 break; 981 case '?': 982 if (*q++ == '\0') 983 return 0; 984 break; 985 case '*': 986 c = *p; 987 if (c != CTLESC && c != '?' && c != '*' && c != '[') { 988 while (*q != c) { 989 if (*q == '\0') 990 return 0; 991 q++; 992 } 993 } 994 do { 995 if (pmatch(p, q)) 996 return 1; 997 } while (*q++ != '\0'); 998 return 0; 999 case '[': { 1000 char *endp; 1001 int invert, found; 1002 char chr; 1003 1004 endp = p; 1005 if (*endp == '!') 1006 endp++; 1007 for (;;) { 1008 if (*endp == '\0') 1009 goto dft; /* no matching ] */ 1010 if (*endp == CTLESC) 1011 endp++; 1012 if (*++endp == ']') 1013 break; 1014 } 1015 invert = 0; 1016 if (*p == '!') { 1017 invert++; 1018 p++; 1019 } 1020 found = 0; 1021 chr = *q++; 1022 c = *p++; 1023 do { 1024 if (c == CTLESC) 1025 c = *p++; 1026 if (*p == '-' && p[1] != ']') { 1027 p++; 1028 if (*p == CTLESC) 1029 p++; 1030 if (chr >= c && chr <= *p) 1031 found = 1; 1032 p++; 1033 } else { 1034 if (chr == c) 1035 found = 1; 1036 } 1037 } while ((c = *p++) != ']'); 1038 if (found == invert) 1039 return 0; 1040 break; 1041 } 1042 dft: default: 1043 if (*q++ != c) 1044 return 0; 1045 break; 1046 } 1047 } 1048 breakloop: 1049 if (*q != '\0') 1050 return 0; 1051 return 1; 1052 } 1053 1054 1055 1056 /* 1057 * Remove any CTLESC characters from a string. 1058 */ 1059 1060 void 1061 rmescapes(str) 1062 char *str; 1063 { 1064 register char *p, *q; 1065 1066 p = str; 1067 while (*p != CTLESC) { 1068 if (*p++ == '\0') 1069 return; 1070 } 1071 q = p; 1072 while (*p) { 1073 if (*p == CTLESC) 1074 p++; 1075 *q++ = *p++; 1076 } 1077 *q = '\0'; 1078 } 1079 1080 1081 1082 /* 1083 * See if a pattern matches in a case statement. 1084 */ 1085 1086 int 1087 casematch(pattern, val) 1088 union node *pattern; 1089 char *val; 1090 { 1091 struct stackmark smark; 1092 int result; 1093 char *p; 1094 1095 setstackmark(&smark); 1096 argbackq = pattern->narg.backquote; 1097 STARTSTACKSTR(expdest); 1098 ifslastp = NULL; 1099 argstr(pattern->narg.text, 0); 1100 STPUTC('\0', expdest); 1101 p = grabstackstr(expdest); 1102 result = patmatch(p, val); 1103 popstackmark(&smark); 1104 return result; 1105 } 1106