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 * %sccs.include.redist.c% 9 */ 10 11 #ifndef lint 12 static char sccsid[] = "@(#)expand.c 5.9 (Berkeley) 07/31/92"; 13 #endif /* not lint */ 14 15 /* 16 * Routines to expand arguments to commands. We have to deal with 17 * backquotes, shell variables, and file metacharacters. 18 */ 19 20 #include "shell.h" 21 #include "main.h" 22 #include "nodes.h" 23 #include "eval.h" 24 #include "expand.h" 25 #include "syntax.h" 26 #include "parser.h" 27 #include "jobs.h" 28 #include "options.h" 29 #include "var.h" 30 #include "input.h" 31 #include "output.h" 32 #include "memalloc.h" 33 #include "error.h" 34 #include "mystring.h" 35 #include <sys/types.h> 36 #include <sys/time.h> 37 #include <sys/stat.h> 38 #include <errno.h> 39 #include <dirent.h> 40 #include <pwd.h> 41 42 /* 43 * Structure specifying which parts of the string should be searched 44 * for IFS characters. 45 */ 46 47 struct ifsregion { 48 struct ifsregion *next; /* next region in list */ 49 int begoff; /* offset of start of region */ 50 int endoff; /* offset of end of region */ 51 int nulonly; /* search for nul bytes only */ 52 }; 53 54 55 char *expdest; /* output of current string */ 56 struct nodelist *argbackq; /* list of back quote expressions */ 57 struct ifsregion ifsfirst; /* first struct in list of ifs regions */ 58 struct ifsregion *ifslastp; /* last struct in list */ 59 struct arglist exparg; /* holds expanded arg list */ 60 61 #ifdef __STDC__ 62 STATIC void argstr(char *, int); 63 STATIC void expbackq(union node *, int, int); 64 STATIC char *evalvar(char *, int); 65 STATIC int varisset(int); 66 STATIC void varvalue(int, int, int); 67 STATIC void recordregion(int, int, int); 68 STATIC void ifsbreakup(char *, struct arglist *); 69 STATIC void expandmeta(struct strlist *, int); 70 STATIC void expmeta(char *, char *); 71 STATIC void expari(int); 72 STATIC void addfname(char *); 73 STATIC struct strlist *expsort(struct strlist *); 74 STATIC struct strlist *msort(struct strlist *, int); 75 STATIC int pmatch(char *, char *); 76 STATIC char *exptilde(char *, int); 77 #else 78 STATIC void argstr(); 79 STATIC void expbackq(); 80 STATIC char *evalvar(); 81 STATIC int varisset(); 82 STATIC void varvalue(); 83 STATIC void recordregion(); 84 STATIC void ifsbreakup(); 85 STATIC void expandmeta(); 86 STATIC void expmeta(); 87 STATIC void expari(); 88 STATIC void addfname(); 89 STATIC struct strlist *expsort(); 90 STATIC struct strlist *msort(); 91 STATIC int pmatch(); 92 STATIC char *exptilde(); 93 #endif 94 95 /* 96 * Expand shell variables and backquotes inside a here document. 97 */ 98 99 void 100 expandhere(arg, fd) 101 union node *arg; /* the document */ 102 int fd; /* where to write the expanded version */ 103 { 104 herefd = fd; 105 expandarg(arg, (struct arglist *)NULL, 0); 106 xwrite(fd, stackblock(), expdest - stackblock()); 107 } 108 109 110 /* 111 * Perform variable substitution and command substitution on an argument, 112 * placing the resulting list of arguments in arglist. If EXP_FULL is true, 113 * perform splitting and file name expansion. When arglist is NULL, perform 114 * here document expansion. 115 */ 116 117 void 118 expandarg(arg, arglist, flag) 119 union node *arg; 120 struct arglist *arglist; 121 { 122 struct strlist *sp; 123 char *p; 124 125 argbackq = arg->narg.backquote; 126 STARTSTACKSTR(expdest); 127 ifsfirst.next = NULL; 128 ifslastp = NULL; 129 argstr(arg->narg.text, flag); 130 if (arglist == NULL) { 131 return; /* here document expanded */ 132 } 133 STPUTC('\0', expdest); 134 p = grabstackstr(expdest); 135 exparg.lastp = &exparg.list; 136 /* 137 * TODO - EXP_REDIR 138 */ 139 if (flag & EXP_FULL) { 140 ifsbreakup(p, &exparg); 141 *exparg.lastp = NULL; 142 exparg.lastp = &exparg.list; 143 expandmeta(exparg.list, flag); 144 } else { 145 if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */ 146 rmescapes(p); 147 sp = (struct strlist *)stalloc(sizeof (struct strlist)); 148 sp->text = p; 149 *exparg.lastp = sp; 150 exparg.lastp = &sp->next; 151 } 152 while (ifsfirst.next != NULL) { 153 struct ifsregion *ifsp; 154 INTOFF; 155 ifsp = ifsfirst.next->next; 156 ckfree(ifsfirst.next); 157 ifsfirst.next = ifsp; 158 INTON; 159 } 160 *exparg.lastp = NULL; 161 if (exparg.list) { 162 *arglist->lastp = exparg.list; 163 arglist->lastp = exparg.lastp; 164 } 165 } 166 167 168 169 /* 170 * Perform variable and command substitution. If EXP_FULL is set, output CTLESC 171 * characters to allow for further processing. Otherwise treat 172 * $@ like $* since no splitting will be performed. 173 */ 174 175 STATIC void 176 argstr(p, flag) 177 register char *p; 178 { 179 register char c; 180 int quotes = flag & (EXP_FULL | EXP_CASE); /* do CTLESC */ 181 int firsteq = 1; 182 183 if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE))) 184 p = exptilde(p, flag); 185 for (;;) { 186 switch (c = *p++) { 187 case '\0': 188 case CTLENDVAR: /* ??? */ 189 goto breakloop; 190 case CTLESC: 191 if (quotes) 192 STPUTC(c, expdest); 193 c = *p++; 194 STPUTC(c, expdest); 195 break; 196 case CTLVAR: 197 p = evalvar(p, flag); 198 break; 199 case CTLBACKQ: 200 case CTLBACKQ|CTLQUOTE: 201 expbackq(argbackq->n, c & CTLQUOTE, flag); 202 argbackq = argbackq->next; 203 break; 204 case CTLENDARI: 205 expari(flag); 206 break; 207 case ':': 208 case '=': 209 /* 210 * sort of a hack - expand tildes in variable 211 * assignments (after the first '=' and after ':'s). 212 */ 213 STPUTC(c, expdest); 214 if (flag & EXP_VARTILDE && *p == '~') { 215 if (c == '=') { 216 if (firsteq) 217 firsteq = 0; 218 else 219 break; 220 } 221 p = exptilde(p, flag); 222 } 223 break; 224 default: 225 STPUTC(c, expdest); 226 } 227 } 228 breakloop:; 229 } 230 231 STATIC char * 232 exptilde(p, flag) 233 char *p; 234 { 235 char c, *startp = p; 236 struct passwd *pw; 237 char *home; 238 int quotes = flag & (EXP_FULL | EXP_CASE); 239 240 while (c = *p) { 241 switch(c) { 242 case CTLESC: 243 return (startp); 244 case ':': 245 if (flag & EXP_VARTILDE) 246 goto done; 247 break; 248 case '/': 249 goto done; 250 } 251 p++; 252 } 253 done: 254 *p = '\0'; 255 if (*(startp+1) == '\0') { 256 if ((home = lookupvar("HOME")) == NULL) 257 goto lose; 258 } else { 259 if ((pw = getpwnam(startp+1)) == NULL) 260 goto lose; 261 home = pw->pw_dir; 262 } 263 if (*home == '\0') 264 goto lose; 265 *p = c; 266 while (c = *home++) { 267 if (quotes && SQSYNTAX[c] == CCTL) 268 STPUTC(CTLESC, expdest); 269 STPUTC(c, expdest); 270 } 271 return (p); 272 lose: 273 *p = c; 274 return (startp); 275 } 276 277 278 /* 279 * Expand arithmetic expression. Backup to start of expression, 280 * evaluate, place result in (backed up) result, adjust string position. 281 */ 282 void 283 expari(flag) 284 { 285 char *p, *start; 286 int result; 287 int quotes = flag & (EXP_FULL | EXP_CASE); 288 289 /* 290 * This routine is slightly over-compilcated for 291 * efficiency. First we make sure there is 292 * enough space for the result, which may be bigger 293 * than the expression if we add exponentation. Next we 294 * scan backwards looking for the start of arithmetic. If the 295 * next previous character is a CTLESC character, then we 296 * have to rescan starting from the beginning since CTLESC 297 * characters have to be processed left to right. 298 */ 299 CHECKSTRSPACE(8, expdest); 300 USTPUTC('\0', expdest); 301 start = stackblock(); 302 p = expdest; 303 while (*p != CTLARI && p >= start) 304 --p; 305 if (*p != CTLARI) 306 error("missing CTLARI (shouldn't happen)"); 307 if (p > start && *(p-1) == CTLESC) 308 for (p = start; *p != CTLARI; p++) 309 if (*p == CTLESC) 310 p++; 311 if (quotes) 312 rmescapes(p+1); 313 result = arith(p+1); 314 fmtstr(p, 10, "%d", result); 315 while (*p++) 316 ; 317 result = expdest - p + 1; 318 STADJUST(-result, expdest); 319 } 320 321 322 /* 323 * Expand stuff in backwards quotes. 324 */ 325 326 STATIC void 327 expbackq(cmd, quoted, flag) 328 union node *cmd; 329 { 330 struct backcmd in; 331 int i; 332 char buf[128]; 333 char *p; 334 char *dest = expdest; 335 struct ifsregion saveifs, *savelastp; 336 struct nodelist *saveargbackq; 337 char lastc; 338 int startloc = dest - stackblock(); 339 char const *syntax = quoted? DQSYNTAX : BASESYNTAX; 340 int saveherefd; 341 int quotes = flag & (EXP_FULL | EXP_CASE); 342 343 INTOFF; 344 saveifs = ifsfirst; 345 savelastp = ifslastp; 346 saveargbackq = argbackq; 347 saveherefd = herefd; 348 herefd = -1; 349 p = grabstackstr(dest); 350 evalbackcmd(cmd, &in); 351 ungrabstackstr(p, dest); 352 ifsfirst = saveifs; 353 ifslastp = savelastp; 354 argbackq = saveargbackq; 355 herefd = saveherefd; 356 357 p = in.buf; 358 lastc = '\0'; 359 for (;;) { 360 if (--in.nleft < 0) { 361 if (in.fd < 0) 362 break; 363 while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR); 364 TRACE(("expbackq: read returns %d\n", i)); 365 if (i <= 0) 366 break; 367 p = buf; 368 in.nleft = i - 1; 369 } 370 lastc = *p++; 371 if (lastc != '\0') { 372 if (quotes && syntax[lastc] == CCTL) 373 STPUTC(CTLESC, dest); 374 STPUTC(lastc, dest); 375 } 376 } 377 if (lastc == '\n') { 378 STUNPUTC(dest); 379 } 380 if (in.fd >= 0) 381 close(in.fd); 382 if (in.buf) 383 ckfree(in.buf); 384 if (in.jp) 385 waitforjob(in.jp); 386 if (quoted == 0) 387 recordregion(startloc, dest - stackblock(), 0); 388 TRACE(("evalbackq: size=%d: \"%.*s\"\n", 389 (dest - stackblock()) - startloc, 390 (dest - stackblock()) - startloc, 391 stackblock() + startloc)); 392 expdest = dest; 393 INTON; 394 } 395 396 397 398 /* 399 * Expand a variable, and return a pointer to the next character in the 400 * input string. 401 */ 402 403 STATIC char * 404 evalvar(p, flag) 405 char *p; 406 { 407 int subtype; 408 int varflags; 409 char *var; 410 char *val; 411 int c; 412 int set; 413 int special; 414 int startloc; 415 int quotes = flag & (EXP_FULL | EXP_CASE); 416 417 varflags = *p++; 418 subtype = varflags & VSTYPE; 419 var = p; 420 special = 0; 421 if (! is_name(*p)) 422 special = 1; 423 p = strchr(p, '=') + 1; 424 again: /* jump here after setting a variable with ${var=text} */ 425 if (special) { 426 set = varisset(*var); 427 val = NULL; 428 } else { 429 val = lookupvar(var); 430 if (val == NULL || (varflags & VSNUL) && val[0] == '\0') { 431 val = NULL; 432 set = 0; 433 } else 434 set = 1; 435 } 436 startloc = expdest - stackblock(); 437 if (set && subtype != VSPLUS) { 438 /* insert the value of the variable */ 439 if (special) { 440 varvalue(*var, varflags & VSQUOTE, flag & EXP_FULL); 441 } else { 442 char const *syntax = (varflags & VSQUOTE)? DQSYNTAX : BASESYNTAX; 443 444 while (*val) { 445 if (quotes && syntax[*val] == CCTL) 446 STPUTC(CTLESC, expdest); 447 STPUTC(*val++, expdest); 448 } 449 } 450 } 451 if (subtype == VSPLUS) 452 set = ! set; 453 if (((varflags & VSQUOTE) == 0 || (*var == '@' && shellparam.nparam != 1)) 454 && (set || subtype == VSNORMAL)) 455 recordregion(startloc, expdest - stackblock(), varflags & VSQUOTE); 456 if (! set && subtype != VSNORMAL) { 457 if (subtype == VSPLUS || subtype == VSMINUS) { 458 argstr(p, flag); 459 } else { 460 char *startp; 461 int saveherefd = herefd; 462 herefd = -1; 463 argstr(p, 0); 464 STACKSTRNUL(expdest); 465 herefd = saveherefd; 466 startp = stackblock() + startloc; 467 if (subtype == VSASSIGN) { 468 setvar(var, startp, 0); 469 STADJUST(startp - expdest, expdest); 470 varflags &=~ VSNUL; 471 goto again; 472 } 473 /* subtype == VSQUESTION */ 474 if (*p != CTLENDVAR) { 475 outfmt(&errout, "%s\n", startp); 476 error((char *)NULL); 477 } 478 error("%.*s: parameter %snot set", p - var - 1, 479 var, (varflags & VSNUL)? "null or " : nullstr); 480 } 481 } 482 if (subtype != VSNORMAL) { /* skip to end of alternative */ 483 int nesting = 1; 484 for (;;) { 485 if ((c = *p++) == CTLESC) 486 p++; 487 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { 488 if (set) 489 argbackq = argbackq->next; 490 } else if (c == CTLVAR) { 491 if ((*p++ & VSTYPE) != VSNORMAL) 492 nesting++; 493 } else if (c == CTLENDVAR) { 494 if (--nesting == 0) 495 break; 496 } 497 } 498 } 499 return p; 500 } 501 502 503 504 /* 505 * Test whether a specialized variable is set. 506 */ 507 508 STATIC int 509 varisset(name) 510 char name; 511 { 512 char **ap; 513 514 if (name == '!') { 515 if (backgndpid == -1) 516 return 0; 517 } else if (name == '@' || name == '*') { 518 if (*shellparam.p == NULL) 519 return 0; 520 } else if ((unsigned)(name -= '1') <= '9' - '1') { 521 ap = shellparam.p; 522 do { 523 if (*ap++ == NULL) 524 return 0; 525 } while (--name >= 0); 526 } 527 return 1; 528 } 529 530 531 532 /* 533 * Add the value of a specialized variable to the stack string. 534 */ 535 536 STATIC void 537 varvalue(name, quoted, allow_split) 538 char name; 539 { 540 int num; 541 char temp[32]; 542 char *p; 543 int i; 544 extern int exitstatus; 545 char sep; 546 char **ap; 547 char const *syntax; 548 549 #define STRTODEST(p) \ 550 do {\ 551 if (allow_split) { \ 552 syntax = quoted? DQSYNTAX : BASESYNTAX; \ 553 while (*p) { \ 554 if (syntax[*p] == CCTL) \ 555 STPUTC(CTLESC, expdest); \ 556 STPUTC(*p++, expdest); \ 557 } \ 558 } else \ 559 while (*p) \ 560 STPUTC(*p++, expdest); \ 561 } while (0) 562 563 564 switch (name) { 565 case '$': 566 num = rootpid; 567 goto numvar; 568 case '?': 569 num = exitstatus; 570 goto numvar; 571 case '#': 572 num = shellparam.nparam; 573 goto numvar; 574 case '!': 575 num = backgndpid; 576 numvar: 577 p = temp + 31; 578 temp[31] = '\0'; 579 do { 580 *--p = num % 10 + '0'; 581 } while ((num /= 10) != 0); 582 while (*p) 583 STPUTC(*p++, expdest); 584 break; 585 case '-': 586 for (i = 0 ; i < NOPTS ; i++) { 587 if (optlist[i].val) 588 STPUTC(optlist[i].letter, expdest); 589 } 590 break; 591 case '@': 592 if (allow_split) { 593 sep = '\0'; 594 goto allargs; 595 } 596 /* fall through */ 597 case '*': 598 sep = ' '; 599 allargs: 600 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 601 STRTODEST(p); 602 if (*ap) 603 STPUTC(sep, expdest); 604 } 605 break; 606 case '0': 607 p = arg0; 608 STRTODEST(p); 609 break; 610 default: 611 if ((unsigned)(name -= '1') <= '9' - '1') { 612 p = shellparam.p[name]; 613 STRTODEST(p); 614 } 615 break; 616 } 617 } 618 619 620 621 /* 622 * Record the the fact that we have to scan this region of the 623 * string for IFS characters. 624 */ 625 626 STATIC void 627 recordregion(start, end, nulonly) { 628 register struct ifsregion *ifsp; 629 630 if (ifslastp == NULL) { 631 ifsp = &ifsfirst; 632 } else { 633 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 634 ifslastp->next = ifsp; 635 } 636 ifslastp = ifsp; 637 ifslastp->next = NULL; 638 ifslastp->begoff = start; 639 ifslastp->endoff = end; 640 ifslastp->nulonly = nulonly; 641 } 642 643 644 645 /* 646 * Break the argument string into pieces based upon IFS and add the 647 * strings to the argument list. The regions of the string to be 648 * searched for IFS characters have been stored by recordregion. 649 */ 650 651 STATIC void 652 ifsbreakup(string, arglist) 653 char *string; 654 struct arglist *arglist; 655 { 656 struct ifsregion *ifsp; 657 struct strlist *sp; 658 char *start; 659 register char *p; 660 char *q; 661 char *ifs; 662 663 start = string; 664 if (ifslastp != NULL) { 665 ifsp = &ifsfirst; 666 do { 667 p = string + ifsp->begoff; 668 ifs = ifsp->nulonly? nullstr : ifsval(); 669 while (p < string + ifsp->endoff) { 670 q = p; 671 if (*p == CTLESC) 672 p++; 673 if (strchr(ifs, *p++)) { 674 if (q > start || *ifs != ' ') { 675 *q = '\0'; 676 sp = (struct strlist *)stalloc(sizeof *sp); 677 sp->text = start; 678 *arglist->lastp = sp; 679 arglist->lastp = &sp->next; 680 } 681 if (*ifs == ' ') { 682 for (;;) { 683 if (p >= string + ifsp->endoff) 684 break; 685 q = p; 686 if (*p == CTLESC) 687 p++; 688 if (strchr(ifs, *p++) == NULL) { 689 p = q; 690 break; 691 } 692 } 693 } 694 start = p; 695 } 696 } 697 } while ((ifsp = ifsp->next) != NULL); 698 if (*start || (*ifs != ' ' && start > string)) { 699 sp = (struct strlist *)stalloc(sizeof *sp); 700 sp->text = start; 701 *arglist->lastp = sp; 702 arglist->lastp = &sp->next; 703 } 704 } else { 705 sp = (struct strlist *)stalloc(sizeof *sp); 706 sp->text = start; 707 *arglist->lastp = sp; 708 arglist->lastp = &sp->next; 709 } 710 } 711 712 713 714 /* 715 * Expand shell metacharacters. At this point, the only control characters 716 * should be escapes. The results are stored in the list exparg. 717 */ 718 719 char *expdir; 720 721 722 STATIC void 723 expandmeta(str, flag) 724 struct strlist *str; 725 { 726 char *p; 727 struct strlist **savelastp; 728 struct strlist *sp; 729 char c; 730 /* TODO - EXP_REDIR */ 731 732 while (str) { 733 if (fflag) 734 goto nometa; 735 p = str->text; 736 for (;;) { /* fast check for meta chars */ 737 if ((c = *p++) == '\0') 738 goto nometa; 739 if (c == '*' || c == '?' || c == '[' || c == '!') 740 break; 741 } 742 savelastp = exparg.lastp; 743 INTOFF; 744 if (expdir == NULL) { 745 int i = strlen(str->text); 746 expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */ 747 } 748 749 expmeta(expdir, str->text); 750 ckfree(expdir); 751 expdir = NULL; 752 INTON; 753 if (exparg.lastp == savelastp) { 754 /* 755 * no matches 756 */ 757 nometa: 758 *exparg.lastp = str; 759 rmescapes(str->text); 760 exparg.lastp = &str->next; 761 } else { 762 *exparg.lastp = NULL; 763 *savelastp = sp = expsort(*savelastp); 764 while (sp->next != NULL) 765 sp = sp->next; 766 exparg.lastp = &sp->next; 767 } 768 str = str->next; 769 } 770 } 771 772 773 /* 774 * Do metacharacter (i.e. *, ?, [...]) expansion. 775 */ 776 777 STATIC void 778 expmeta(enddir, name) 779 char *enddir; 780 char *name; 781 { 782 register char *p; 783 char *q; 784 char *start; 785 char *endname; 786 int metaflag; 787 struct stat statb; 788 DIR *dirp; 789 struct dirent *dp; 790 int atend; 791 int matchdot; 792 793 metaflag = 0; 794 start = name; 795 for (p = name ; ; p++) { 796 if (*p == '*' || *p == '?') 797 metaflag = 1; 798 else if (*p == '[') { 799 q = p + 1; 800 if (*q == '!') 801 q++; 802 for (;;) { 803 if (*q == CTLESC) 804 q++; 805 if (*q == '/' || *q == '\0') 806 break; 807 if (*++q == ']') { 808 metaflag = 1; 809 break; 810 } 811 } 812 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 813 metaflag = 1; 814 } else if (*p == '\0') 815 break; 816 else if (*p == CTLESC) 817 p++; 818 if (*p == '/') { 819 if (metaflag) 820 break; 821 start = p + 1; 822 } 823 } 824 if (metaflag == 0) { /* we've reached the end of the file name */ 825 if (enddir != expdir) 826 metaflag++; 827 for (p = name ; ; p++) { 828 if (*p == CTLESC) 829 p++; 830 *enddir++ = *p; 831 if (*p == '\0') 832 break; 833 } 834 if (metaflag == 0 || stat(expdir, &statb) >= 0) 835 addfname(expdir); 836 return; 837 } 838 endname = p; 839 if (start != name) { 840 p = name; 841 while (p < start) { 842 if (*p == CTLESC) 843 p++; 844 *enddir++ = *p++; 845 } 846 } 847 if (enddir == expdir) { 848 p = "."; 849 } else if (enddir == expdir + 1 && *expdir == '/') { 850 p = "/"; 851 } else { 852 p = expdir; 853 enddir[-1] = '\0'; 854 } 855 if ((dirp = opendir(p)) == NULL) 856 return; 857 if (enddir != expdir) 858 enddir[-1] = '/'; 859 if (*endname == 0) { 860 atend = 1; 861 } else { 862 atend = 0; 863 *endname++ = '\0'; 864 } 865 matchdot = 0; 866 if (start[0] == '.' || start[0] == CTLESC && start[1] == '.') 867 matchdot++; 868 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 869 if (dp->d_name[0] == '.' && ! matchdot) 870 continue; 871 if (patmatch(start, dp->d_name)) { 872 if (atend) { 873 scopy(dp->d_name, enddir); 874 addfname(expdir); 875 } else { 876 char *q; 877 for (p = enddir, q = dp->d_name ; *p++ = *q++ ;); 878 p[-1] = '/'; 879 expmeta(p, endname); 880 } 881 } 882 } 883 closedir(dirp); 884 if (! atend) 885 endname[-1] = '/'; 886 } 887 888 889 /* 890 * Add a file name to the list. 891 */ 892 893 STATIC void 894 addfname(name) 895 char *name; 896 { 897 char *p; 898 struct strlist *sp; 899 900 p = stalloc(strlen(name) + 1); 901 scopy(name, p); 902 sp = (struct strlist *)stalloc(sizeof *sp); 903 sp->text = p; 904 *exparg.lastp = sp; 905 exparg.lastp = &sp->next; 906 } 907 908 909 /* 910 * Sort the results of file name expansion. It calculates the number of 911 * strings to sort and then calls msort (short for merge sort) to do the 912 * work. 913 */ 914 915 STATIC struct strlist * 916 expsort(str) 917 struct strlist *str; 918 { 919 int len; 920 struct strlist *sp; 921 922 len = 0; 923 for (sp = str ; sp ; sp = sp->next) 924 len++; 925 return msort(str, len); 926 } 927 928 929 STATIC struct strlist * 930 msort(list, len) 931 struct strlist *list; 932 { 933 struct strlist *p, *q; 934 struct strlist **lpp; 935 int half; 936 int n; 937 938 if (len <= 1) 939 return list; 940 half = len >> 1; 941 p = list; 942 for (n = half ; --n >= 0 ; ) { 943 q = p; 944 p = p->next; 945 } 946 q->next = NULL; /* terminate first half of list */ 947 q = msort(list, half); /* sort first half of list */ 948 p = msort(p, len - half); /* sort second half */ 949 lpp = &list; 950 for (;;) { 951 if (strcmp(p->text, q->text) < 0) { 952 *lpp = p; 953 lpp = &p->next; 954 if ((p = *lpp) == NULL) { 955 *lpp = q; 956 break; 957 } 958 } else { 959 *lpp = q; 960 lpp = &q->next; 961 if ((q = *lpp) == NULL) { 962 *lpp = p; 963 break; 964 } 965 } 966 } 967 return list; 968 } 969 970 971 972 /* 973 * Returns true if the pattern matches the string. 974 */ 975 976 int 977 patmatch(pattern, string) 978 char *pattern; 979 char *string; 980 { 981 #ifdef notdef 982 if (pattern[0] == '!' && pattern[1] == '!') 983 return 1 - pmatch(pattern + 2, string); 984 else 985 #endif 986 return pmatch(pattern, string); 987 } 988 989 990 STATIC int 991 pmatch(pattern, string) 992 char *pattern; 993 char *string; 994 { 995 register char *p, *q; 996 register char c; 997 998 p = pattern; 999 q = string; 1000 for (;;) { 1001 switch (c = *p++) { 1002 case '\0': 1003 goto breakloop; 1004 case CTLESC: 1005 if (*q++ != *p++) 1006 return 0; 1007 break; 1008 case '?': 1009 if (*q++ == '\0') 1010 return 0; 1011 break; 1012 case '*': 1013 c = *p; 1014 if (c != CTLESC && c != '?' && c != '*' && c != '[') { 1015 while (*q != c) { 1016 if (*q == '\0') 1017 return 0; 1018 q++; 1019 } 1020 } 1021 do { 1022 if (pmatch(p, q)) 1023 return 1; 1024 } while (*q++ != '\0'); 1025 return 0; 1026 case '[': { 1027 char *endp; 1028 int invert, found; 1029 char chr; 1030 1031 endp = p; 1032 if (*endp == '!') 1033 endp++; 1034 for (;;) { 1035 if (*endp == '\0') 1036 goto dft; /* no matching ] */ 1037 if (*endp == CTLESC) 1038 endp++; 1039 if (*++endp == ']') 1040 break; 1041 } 1042 invert = 0; 1043 if (*p == '!') { 1044 invert++; 1045 p++; 1046 } 1047 found = 0; 1048 chr = *q++; 1049 c = *p++; 1050 do { 1051 if (c == CTLESC) 1052 c = *p++; 1053 if (*p == '-' && p[1] != ']') { 1054 p++; 1055 if (*p == CTLESC) 1056 p++; 1057 if (chr >= c && chr <= *p) 1058 found = 1; 1059 p++; 1060 } else { 1061 if (chr == c) 1062 found = 1; 1063 } 1064 } while ((c = *p++) != ']'); 1065 if (found == invert) 1066 return 0; 1067 break; 1068 } 1069 dft: default: 1070 if (*q++ != c) 1071 return 0; 1072 break; 1073 } 1074 } 1075 breakloop: 1076 if (*q != '\0') 1077 return 0; 1078 return 1; 1079 } 1080 1081 1082 1083 /* 1084 * Remove any CTLESC characters from a string. 1085 */ 1086 1087 void 1088 rmescapes(str) 1089 char *str; 1090 { 1091 register char *p, *q; 1092 1093 p = str; 1094 while (*p != CTLESC) { 1095 if (*p++ == '\0') 1096 return; 1097 } 1098 q = p; 1099 while (*p) { 1100 if (*p == CTLESC) 1101 p++; 1102 *q++ = *p++; 1103 } 1104 *q = '\0'; 1105 } 1106 1107 1108 1109 /* 1110 * See if a pattern matches in a case statement. 1111 */ 1112 1113 int 1114 casematch(pattern, val) 1115 union node *pattern; 1116 char *val; 1117 { 1118 struct stackmark smark; 1119 int result; 1120 char *p; 1121 1122 setstackmark(&smark); 1123 argbackq = pattern->narg.backquote; 1124 STARTSTACKSTR(expdest); 1125 ifslastp = NULL; 1126 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); 1127 STPUTC('\0', expdest); 1128 p = grabstackstr(expdest); 1129 result = patmatch(p, val); 1130 popstackmark(&smark); 1131 return result; 1132 } 1133