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 37 #ifndef lint 38 /*static char sccsid[] = "from: @(#)expand.c 8.2 (Berkeley) 10/22/93";*/ 39 static char *rcsid = "$Id: expand.c,v 1.12 1994/12/04 07:12:11 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/time.h> 64 #include <sys/stat.h> 65 #include <errno.h> 66 #include <dirent.h> 67 #include <unistd.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 int flag; 150 { 151 struct strlist *sp; 152 char *p; 153 154 argbackq = arg->narg.backquote; 155 STARTSTACKSTR(expdest); 156 ifsfirst.next = NULL; 157 ifslastp = NULL; 158 argstr(arg->narg.text, flag); 159 if (arglist == NULL) { 160 return; /* here document expanded */ 161 } 162 STPUTC('\0', expdest); 163 p = grabstackstr(expdest); 164 exparg.lastp = &exparg.list; 165 /* 166 * TODO - EXP_REDIR 167 */ 168 if (flag & EXP_FULL) { 169 ifsbreakup(p, &exparg); 170 *exparg.lastp = NULL; 171 exparg.lastp = &exparg.list; 172 expandmeta(exparg.list, flag); 173 } else { 174 if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */ 175 rmescapes(p); 176 sp = (struct strlist *)stalloc(sizeof (struct strlist)); 177 sp->text = p; 178 *exparg.lastp = sp; 179 exparg.lastp = &sp->next; 180 } 181 while (ifsfirst.next != NULL) { 182 struct ifsregion *ifsp; 183 INTOFF; 184 ifsp = ifsfirst.next->next; 185 ckfree(ifsfirst.next); 186 ifsfirst.next = ifsp; 187 INTON; 188 } 189 *exparg.lastp = NULL; 190 if (exparg.list) { 191 *arglist->lastp = exparg.list; 192 arglist->lastp = exparg.lastp; 193 } 194 } 195 196 197 198 /* 199 * Perform variable and command substitution. If EXP_FULL is set, output CTLESC 200 * characters to allow for further processing. Otherwise treat 201 * $@ like $* since no splitting will be performed. 202 */ 203 204 STATIC void 205 argstr(p, flag) 206 register char *p; 207 int flag; 208 { 209 register char c; 210 int quotes = flag & (EXP_FULL | EXP_CASE); /* do CTLESC */ 211 int firsteq = 1; 212 213 if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE))) 214 p = exptilde(p, flag); 215 for (;;) { 216 switch (c = *p++) { 217 case '\0': 218 case CTLENDVAR: /* ??? */ 219 goto breakloop; 220 case CTLESC: 221 if (quotes) 222 STPUTC(c, expdest); 223 c = *p++; 224 STPUTC(c, expdest); 225 break; 226 case CTLVAR: 227 p = evalvar(p, flag); 228 break; 229 case CTLBACKQ: 230 case CTLBACKQ|CTLQUOTE: 231 expbackq(argbackq->n, c & CTLQUOTE, flag); 232 argbackq = argbackq->next; 233 break; 234 case CTLENDARI: 235 expari(flag); 236 break; 237 case ':': 238 case '=': 239 /* 240 * sort of a hack - expand tildes in variable 241 * assignments (after the first '=' and after ':'s). 242 */ 243 STPUTC(c, expdest); 244 if (flag & EXP_VARTILDE && *p == '~') { 245 if (c == '=') { 246 if (firsteq) 247 firsteq = 0; 248 else 249 break; 250 } 251 p = exptilde(p, flag); 252 } 253 break; 254 default: 255 STPUTC(c, expdest); 256 } 257 } 258 breakloop:; 259 } 260 261 STATIC char * 262 exptilde(p, flag) 263 char *p; 264 int flag; 265 { 266 char c, *startp = p; 267 struct passwd *pw; 268 char *home; 269 int quotes = flag & (EXP_FULL | EXP_CASE); 270 271 while (c = *p) { 272 switch(c) { 273 case CTLESC: 274 return (startp); 275 case ':': 276 if (flag & EXP_VARTILDE) 277 goto done; 278 break; 279 case '/': 280 goto done; 281 } 282 p++; 283 } 284 done: 285 *p = '\0'; 286 if (*(startp+1) == '\0') { 287 if ((home = lookupvar("HOME")) == NULL) 288 goto lose; 289 } else { 290 if ((pw = getpwnam(startp+1)) == NULL) 291 goto lose; 292 home = pw->pw_dir; 293 } 294 if (*home == '\0') 295 goto lose; 296 *p = c; 297 while (c = *home++) { 298 if (quotes && SQSYNTAX[c] == CCTL) 299 STPUTC(CTLESC, expdest); 300 STPUTC(c, expdest); 301 } 302 return (p); 303 lose: 304 *p = c; 305 return (startp); 306 } 307 308 309 /* 310 * Expand arithmetic expression. Backup to start of expression, 311 * evaluate, place result in (backed up) result, adjust string position. 312 */ 313 void 314 expari(flag) 315 int flag; 316 { 317 char *p, *start; 318 int result; 319 int quotes = flag & (EXP_FULL | EXP_CASE); 320 321 /* 322 * This routine is slightly over-compilcated for 323 * efficiency. First we make sure there is 324 * enough space for the result, which may be bigger 325 * than the expression if we add exponentation. Next we 326 * scan backwards looking for the start of arithmetic. If the 327 * next previous character is a CTLESC character, then we 328 * have to rescan starting from the beginning since CTLESC 329 * characters have to be processed left to right. 330 */ 331 CHECKSTRSPACE(8, expdest); 332 USTPUTC('\0', expdest); 333 start = stackblock(); 334 p = expdest; 335 while (*p != CTLARI && p >= start) 336 --p; 337 if (*p != CTLARI) 338 error("missing CTLARI (shouldn't happen)"); 339 if (p > start && *(p-1) == CTLESC) 340 for (p = start; *p != CTLARI; p++) 341 if (*p == CTLESC) 342 p++; 343 if (quotes) 344 rmescapes(p+1); 345 result = arith(p+1); 346 fmtstr(p, 10, "%d", result); 347 while (*p++) 348 ; 349 result = expdest - p + 1; 350 STADJUST(-result, expdest); 351 } 352 353 354 /* 355 * Expand stuff in backwards quotes. 356 */ 357 358 STATIC void 359 expbackq(cmd, quoted, flag) 360 union node *cmd; 361 int quoted; 362 int flag; 363 { 364 struct backcmd in; 365 int i; 366 char buf[128]; 367 char *p; 368 char *dest = expdest; 369 struct ifsregion saveifs, *savelastp; 370 struct nodelist *saveargbackq; 371 char lastc; 372 int startloc = dest - stackblock(); 373 char const *syntax = quoted? DQSYNTAX : BASESYNTAX; 374 int saveherefd; 375 int quotes = flag & (EXP_FULL | EXP_CASE); 376 377 INTOFF; 378 saveifs = ifsfirst; 379 savelastp = ifslastp; 380 saveargbackq = argbackq; 381 saveherefd = herefd; 382 herefd = -1; 383 p = grabstackstr(dest); 384 evalbackcmd(cmd, &in); 385 ungrabstackstr(p, dest); 386 ifsfirst = saveifs; 387 ifslastp = savelastp; 388 argbackq = saveargbackq; 389 herefd = saveherefd; 390 391 p = in.buf; 392 lastc = '\0'; 393 for (;;) { 394 if (--in.nleft < 0) { 395 if (in.fd < 0) 396 break; 397 while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR); 398 TRACE(("expbackq: read returns %d\n", i)); 399 if (i <= 0) 400 break; 401 p = buf; 402 in.nleft = i - 1; 403 } 404 lastc = *p++; 405 if (lastc != '\0') { 406 if (quotes && syntax[lastc] == CCTL) 407 STPUTC(CTLESC, dest); 408 STPUTC(lastc, dest); 409 } 410 } 411 if (lastc == '\n') { 412 STUNPUTC(dest); 413 } 414 if (in.fd >= 0) 415 close(in.fd); 416 if (in.buf) 417 ckfree(in.buf); 418 if (in.jp) 419 exitstatus = waitforjob(in.jp); 420 if (quoted == 0) 421 recordregion(startloc, dest - stackblock(), 0); 422 TRACE(("evalbackq: size=%d: \"%.*s\"\n", 423 (dest - stackblock()) - startloc, 424 (dest - stackblock()) - startloc, 425 stackblock() + startloc)); 426 expdest = dest; 427 INTON; 428 } 429 430 431 432 /* 433 * Expand a variable, and return a pointer to the next character in the 434 * input string. 435 */ 436 437 STATIC char * 438 evalvar(p, flag) 439 char *p; 440 int flag; 441 { 442 int subtype; 443 int varflags; 444 char *var; 445 char *val; 446 int c; 447 int set; 448 int special; 449 int startloc; 450 int quotes = flag & (EXP_FULL | EXP_CASE); 451 452 varflags = *p++; 453 subtype = varflags & VSTYPE; 454 var = p; 455 special = 0; 456 if (! is_name(*p)) 457 special = 1; 458 p = strchr(p, '=') + 1; 459 again: /* jump here after setting a variable with ${var=text} */ 460 if (special) { 461 set = varisset(*var); 462 val = NULL; 463 } else { 464 val = lookupvar(var); 465 if (val == NULL || (varflags & VSNUL) && val[0] == '\0') { 466 val = NULL; 467 set = 0; 468 } else 469 set = 1; 470 } 471 startloc = expdest - stackblock(); 472 if (set && subtype != VSPLUS) { 473 /* insert the value of the variable */ 474 if (special) { 475 varvalue(*var, varflags & VSQUOTE, flag & EXP_FULL); 476 } else { 477 char const *syntax = (varflags & VSQUOTE)? DQSYNTAX : BASESYNTAX; 478 479 while (*val) { 480 if (quotes && syntax[*val] == CCTL) 481 STPUTC(CTLESC, expdest); 482 STPUTC(*val++, expdest); 483 } 484 } 485 } 486 if (subtype == VSPLUS) 487 set = ! set; 488 if (((varflags & VSQUOTE) == 0 || (*var == '@' && shellparam.nparam != 1)) 489 && (set || subtype == VSNORMAL)) 490 recordregion(startloc, expdest - stackblock(), varflags & VSQUOTE); 491 if (! set && subtype != VSNORMAL) { 492 if (subtype == VSPLUS || subtype == VSMINUS) { 493 argstr(p, flag); 494 } else { 495 char *startp; 496 int saveherefd = herefd; 497 struct nodelist *saveargbackq = argbackq; 498 herefd = -1; 499 argstr(p, 0); 500 STACKSTRNUL(expdest); 501 herefd = saveherefd; 502 argbackq = saveargbackq; 503 startp = stackblock() + startloc; 504 if (subtype == VSASSIGN) { 505 setvar(var, startp, 0); 506 STADJUST(startp - expdest, expdest); 507 varflags &=~ VSNUL; 508 goto again; 509 } 510 /* subtype == VSQUESTION */ 511 if (*p != CTLENDVAR) { 512 outfmt(&errout, "%s\n", startp); 513 error((char *)NULL); 514 } 515 error("%.*s: parameter %snot set", p - var - 1, 516 var, (varflags & VSNUL)? "null or " : nullstr); 517 } 518 } 519 if (subtype != VSNORMAL) { /* skip to end of alternative */ 520 int nesting = 1; 521 for (;;) { 522 if ((c = *p++) == CTLESC) 523 p++; 524 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { 525 if (set) 526 argbackq = argbackq->next; 527 } else if (c == CTLVAR) { 528 if ((*p++ & VSTYPE) != VSNORMAL) 529 nesting++; 530 } else if (c == CTLENDVAR) { 531 if (--nesting == 0) 532 break; 533 } 534 } 535 } 536 return p; 537 } 538 539 540 541 /* 542 * Test whether a specialized variable is set. 543 */ 544 545 STATIC int 546 varisset(name) 547 char name; 548 { 549 char **ap; 550 551 if (name == '!') { 552 if (backgndpid == -1) 553 return 0; 554 } else if (name == '@' || name == '*') { 555 if (*shellparam.p == NULL) 556 return 0; 557 } else if ((unsigned)(name -= '1') <= '9' - '1') { 558 ap = shellparam.p; 559 do { 560 if (*ap++ == NULL) 561 return 0; 562 } while (--name >= 0); 563 } 564 return 1; 565 } 566 567 568 569 /* 570 * Add the value of a specialized variable to the stack string. 571 */ 572 573 STATIC void 574 varvalue(name, quoted, allow_split) 575 char name; 576 int quoted; 577 int allow_split; 578 { 579 int num; 580 char temp[32]; 581 char *p; 582 int i; 583 extern int exitstatus; 584 char sep; 585 char **ap; 586 char const *syntax; 587 588 #define STRTODEST(p) \ 589 do {\ 590 if (allow_split) { \ 591 syntax = quoted? DQSYNTAX : BASESYNTAX; \ 592 while (*p) { \ 593 if (syntax[*p] == CCTL) \ 594 STPUTC(CTLESC, expdest); \ 595 STPUTC(*p++, expdest); \ 596 } \ 597 } else \ 598 while (*p) \ 599 STPUTC(*p++, expdest); \ 600 } while (0) 601 602 603 switch (name) { 604 case '$': 605 num = rootpid; 606 goto numvar; 607 case '?': 608 num = exitstatus; 609 goto numvar; 610 case '#': 611 num = shellparam.nparam; 612 goto numvar; 613 case '!': 614 num = backgndpid; 615 numvar: 616 p = temp + 31; 617 temp[31] = '\0'; 618 do { 619 *--p = num % 10 + '0'; 620 } while ((num /= 10) != 0); 621 while (*p) 622 STPUTC(*p++, expdest); 623 break; 624 case '-': 625 for (i = 0 ; i < NOPTS ; i++) { 626 if (optlist[i].val) 627 STPUTC(optlist[i].letter, expdest); 628 } 629 break; 630 case '@': 631 if (allow_split) { 632 sep = '\0'; 633 goto allargs; 634 } 635 /* fall through */ 636 case '*': 637 sep = ' '; 638 allargs: 639 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 640 STRTODEST(p); 641 if (*ap) 642 STPUTC(sep, expdest); 643 } 644 break; 645 case '0': 646 p = arg0; 647 STRTODEST(p); 648 break; 649 default: 650 if ((unsigned)(name -= '1') <= '9' - '1') { 651 p = shellparam.p[name]; 652 STRTODEST(p); 653 } 654 break; 655 } 656 } 657 658 659 660 /* 661 * Record the the fact that we have to scan this region of the 662 * string for IFS characters. 663 */ 664 665 STATIC void 666 recordregion(start, end, nulonly) 667 int start; 668 int end; 669 int nulonly; 670 { 671 register struct ifsregion *ifsp; 672 673 if (ifslastp == NULL) { 674 ifsp = &ifsfirst; 675 } else { 676 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 677 ifslastp->next = ifsp; 678 } 679 ifslastp = ifsp; 680 ifslastp->next = NULL; 681 ifslastp->begoff = start; 682 ifslastp->endoff = end; 683 ifslastp->nulonly = nulonly; 684 } 685 686 687 688 /* 689 * Break the argument string into pieces based upon IFS and add the 690 * strings to the argument list. The regions of the string to be 691 * searched for IFS characters have been stored by recordregion. 692 */ 693 694 STATIC void 695 ifsbreakup(string, arglist) 696 char *string; 697 struct arglist *arglist; 698 { 699 struct ifsregion *ifsp; 700 struct strlist *sp; 701 char *start; 702 register char *p; 703 char *q; 704 char *ifs; 705 706 start = string; 707 if (ifslastp != NULL) { 708 ifsp = &ifsfirst; 709 do { 710 p = string + ifsp->begoff; 711 ifs = ifsp->nulonly? nullstr : ifsval(); 712 while (p < string + ifsp->endoff) { 713 q = p; 714 if (*p == CTLESC) 715 p++; 716 if (strchr(ifs, *p++)) { 717 if (q > start || *ifs != ' ') { 718 *q = '\0'; 719 sp = (struct strlist *)stalloc(sizeof *sp); 720 sp->text = start; 721 *arglist->lastp = sp; 722 arglist->lastp = &sp->next; 723 } 724 if (*ifs == ' ') { 725 for (;;) { 726 if (p >= string + ifsp->endoff) 727 break; 728 q = p; 729 if (*p == CTLESC) 730 p++; 731 if (strchr(ifs, *p++) == NULL) { 732 p = q; 733 break; 734 } 735 } 736 } 737 start = p; 738 } 739 } 740 } while ((ifsp = ifsp->next) != NULL); 741 if (*start || (*ifs != ' ' && start > string)) { 742 sp = (struct strlist *)stalloc(sizeof *sp); 743 sp->text = start; 744 *arglist->lastp = sp; 745 arglist->lastp = &sp->next; 746 } 747 } else { 748 sp = (struct strlist *)stalloc(sizeof *sp); 749 sp->text = start; 750 *arglist->lastp = sp; 751 arglist->lastp = &sp->next; 752 } 753 } 754 755 756 757 /* 758 * Expand shell metacharacters. At this point, the only control characters 759 * should be escapes. The results are stored in the list exparg. 760 */ 761 762 char *expdir; 763 764 765 STATIC void 766 expandmeta(str, flag) 767 struct strlist *str; 768 int flag; 769 { 770 char *p; 771 struct strlist **savelastp; 772 struct strlist *sp; 773 char c; 774 /* TODO - EXP_REDIR */ 775 776 while (str) { 777 if (fflag) 778 goto nometa; 779 p = str->text; 780 for (;;) { /* fast check for meta chars */ 781 if ((c = *p++) == '\0') 782 goto nometa; 783 if (c == '*' || c == '?' || c == '[' || c == '!') 784 break; 785 } 786 savelastp = exparg.lastp; 787 INTOFF; 788 if (expdir == NULL) { 789 int i = strlen(str->text); 790 expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */ 791 } 792 793 expmeta(expdir, str->text); 794 ckfree(expdir); 795 expdir = NULL; 796 INTON; 797 if (exparg.lastp == savelastp) { 798 /* 799 * no matches 800 */ 801 nometa: 802 *exparg.lastp = str; 803 rmescapes(str->text); 804 exparg.lastp = &str->next; 805 } else { 806 *exparg.lastp = NULL; 807 *savelastp = sp = expsort(*savelastp); 808 while (sp->next != NULL) 809 sp = sp->next; 810 exparg.lastp = &sp->next; 811 } 812 str = str->next; 813 } 814 } 815 816 817 /* 818 * Do metacharacter (i.e. *, ?, [...]) expansion. 819 */ 820 821 STATIC void 822 expmeta(enddir, name) 823 char *enddir; 824 char *name; 825 { 826 register char *p; 827 char *q; 828 char *start; 829 char *endname; 830 int metaflag; 831 struct stat statb; 832 DIR *dirp; 833 struct dirent *dp; 834 int atend; 835 int matchdot; 836 837 metaflag = 0; 838 start = name; 839 for (p = name ; ; p++) { 840 if (*p == '*' || *p == '?') 841 metaflag = 1; 842 else if (*p == '[') { 843 q = p + 1; 844 if (*q == '!') 845 q++; 846 for (;;) { 847 if (*q == CTLESC) 848 q++; 849 if (*q == '/' || *q == '\0') 850 break; 851 if (*++q == ']') { 852 metaflag = 1; 853 break; 854 } 855 } 856 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 857 metaflag = 1; 858 } else if (*p == '\0') 859 break; 860 else if (*p == CTLESC) 861 p++; 862 if (*p == '/') { 863 if (metaflag) 864 break; 865 start = p + 1; 866 } 867 } 868 if (metaflag == 0) { /* we've reached the end of the file name */ 869 if (enddir != expdir) 870 metaflag++; 871 for (p = name ; ; p++) { 872 if (*p == CTLESC) 873 p++; 874 *enddir++ = *p; 875 if (*p == '\0') 876 break; 877 } 878 if (metaflag == 0 || stat(expdir, &statb) >= 0) 879 addfname(expdir); 880 return; 881 } 882 endname = p; 883 if (start != name) { 884 p = name; 885 while (p < start) { 886 if (*p == CTLESC) 887 p++; 888 *enddir++ = *p++; 889 } 890 } 891 if (enddir == expdir) { 892 p = "."; 893 } else if (enddir == expdir + 1 && *expdir == '/') { 894 p = "/"; 895 } else { 896 p = expdir; 897 enddir[-1] = '\0'; 898 } 899 if ((dirp = opendir(p)) == NULL) 900 return; 901 if (enddir != expdir) 902 enddir[-1] = '/'; 903 if (*endname == 0) { 904 atend = 1; 905 } else { 906 atend = 0; 907 *endname++ = '\0'; 908 } 909 matchdot = 0; 910 if (start[0] == '.' || start[0] == CTLESC && start[1] == '.') 911 matchdot++; 912 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 913 if (dp->d_name[0] == '.' && ! matchdot) 914 continue; 915 if (patmatch(start, dp->d_name)) { 916 if (atend) { 917 scopy(dp->d_name, enddir); 918 addfname(expdir); 919 } else { 920 char *q; 921 for (p = enddir, q = dp->d_name ; *p++ = *q++ ;); 922 p[-1] = '/'; 923 expmeta(p, endname); 924 } 925 } 926 } 927 closedir(dirp); 928 if (! atend) 929 endname[-1] = '/'; 930 } 931 932 933 /* 934 * Add a file name to the list. 935 */ 936 937 STATIC void 938 addfname(name) 939 char *name; 940 { 941 char *p; 942 struct strlist *sp; 943 944 p = stalloc(strlen(name) + 1); 945 scopy(name, p); 946 sp = (struct strlist *)stalloc(sizeof *sp); 947 sp->text = p; 948 *exparg.lastp = sp; 949 exparg.lastp = &sp->next; 950 } 951 952 953 /* 954 * Sort the results of file name expansion. It calculates the number of 955 * strings to sort and then calls msort (short for merge sort) to do the 956 * work. 957 */ 958 959 STATIC struct strlist * 960 expsort(str) 961 struct strlist *str; 962 { 963 int len; 964 struct strlist *sp; 965 966 len = 0; 967 for (sp = str ; sp ; sp = sp->next) 968 len++; 969 return msort(str, len); 970 } 971 972 973 STATIC struct strlist * 974 msort(list, len) 975 struct strlist *list; 976 int len; 977 { 978 struct strlist *p, *q; 979 struct strlist **lpp; 980 int half; 981 int n; 982 983 if (len <= 1) 984 return list; 985 half = len >> 1; 986 p = list; 987 for (n = half ; --n >= 0 ; ) { 988 q = p; 989 p = p->next; 990 } 991 q->next = NULL; /* terminate first half of list */ 992 q = msort(list, half); /* sort first half of list */ 993 p = msort(p, len - half); /* sort second half */ 994 lpp = &list; 995 for (;;) { 996 if (strcmp(p->text, q->text) < 0) { 997 *lpp = p; 998 lpp = &p->next; 999 if ((p = *lpp) == NULL) { 1000 *lpp = q; 1001 break; 1002 } 1003 } else { 1004 *lpp = q; 1005 lpp = &q->next; 1006 if ((q = *lpp) == NULL) { 1007 *lpp = p; 1008 break; 1009 } 1010 } 1011 } 1012 return list; 1013 } 1014 1015 1016 1017 /* 1018 * Returns true if the pattern matches the string. 1019 */ 1020 1021 int 1022 patmatch(pattern, string) 1023 char *pattern; 1024 char *string; 1025 { 1026 #ifdef notdef 1027 if (pattern[0] == '!' && pattern[1] == '!') 1028 return 1 - pmatch(pattern + 2, string); 1029 else 1030 #endif 1031 return pmatch(pattern, string); 1032 } 1033 1034 1035 STATIC int 1036 pmatch(pattern, string) 1037 char *pattern; 1038 char *string; 1039 { 1040 register char *p, *q; 1041 register char c; 1042 1043 p = pattern; 1044 q = string; 1045 for (;;) { 1046 switch (c = *p++) { 1047 case '\0': 1048 goto breakloop; 1049 case CTLESC: 1050 if (*q++ != *p++) 1051 return 0; 1052 break; 1053 case '?': 1054 if (*q++ == '\0') 1055 return 0; 1056 break; 1057 case '*': 1058 c = *p; 1059 if (c != CTLESC && c != '?' && c != '*' && c != '[') { 1060 while (*q != c) { 1061 if (*q == '\0') 1062 return 0; 1063 q++; 1064 } 1065 } 1066 do { 1067 if (pmatch(p, q)) 1068 return 1; 1069 } while (*q++ != '\0'); 1070 return 0; 1071 case '[': { 1072 char *endp; 1073 int invert, found; 1074 char chr; 1075 1076 endp = p; 1077 if (*endp == '!') 1078 endp++; 1079 for (;;) { 1080 if (*endp == '\0') 1081 goto dft; /* no matching ] */ 1082 if (*endp == CTLESC) 1083 endp++; 1084 if (*++endp == ']') 1085 break; 1086 } 1087 invert = 0; 1088 if (*p == '!') { 1089 invert++; 1090 p++; 1091 } 1092 found = 0; 1093 chr = *q++; 1094 if (chr == '\0') 1095 return 0; 1096 c = *p++; 1097 do { 1098 if (c == CTLESC) 1099 c = *p++; 1100 if (*p == '-' && p[1] != ']') { 1101 p++; 1102 if (*p == CTLESC) 1103 p++; 1104 if (chr >= c && chr <= *p) 1105 found = 1; 1106 p++; 1107 } else { 1108 if (chr == c) 1109 found = 1; 1110 } 1111 } while ((c = *p++) != ']'); 1112 if (found == invert) 1113 return 0; 1114 break; 1115 } 1116 dft: default: 1117 if (*q++ != c) 1118 return 0; 1119 break; 1120 } 1121 } 1122 breakloop: 1123 if (*q != '\0') 1124 return 0; 1125 return 1; 1126 } 1127 1128 1129 1130 /* 1131 * Remove any CTLESC characters from a string. 1132 */ 1133 1134 void 1135 rmescapes(str) 1136 char *str; 1137 { 1138 register char *p, *q; 1139 1140 p = str; 1141 while (*p != CTLESC) { 1142 if (*p++ == '\0') 1143 return; 1144 } 1145 q = p; 1146 while (*p) { 1147 if (*p == CTLESC) 1148 p++; 1149 *q++ = *p++; 1150 } 1151 *q = '\0'; 1152 } 1153 1154 1155 1156 /* 1157 * See if a pattern matches in a case statement. 1158 */ 1159 1160 int 1161 casematch(pattern, val) 1162 union node *pattern; 1163 char *val; 1164 { 1165 struct stackmark smark; 1166 int result; 1167 char *p; 1168 1169 setstackmark(&smark); 1170 argbackq = pattern->narg.backquote; 1171 STARTSTACKSTR(expdest); 1172 ifslastp = NULL; 1173 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); 1174 STPUTC('\0', expdest); 1175 p = grabstackstr(expdest); 1176 result = patmatch(p, val); 1177 popstackmark(&smark); 1178 return result; 1179 } 1180