1 /*- 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Kenneth Almquist. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * $Id: expand.c,v 1.12 1996/12/14 06:19:16 steve Exp $ 37 */ 38 39 #ifndef lint 40 static char const sccsid[] = "@(#)expand.c 8.5 (Berkeley) 5/15/95"; 41 #endif /* not lint */ 42 43 #include <sys/types.h> 44 #include <sys/time.h> 45 #include <sys/stat.h> 46 #include <errno.h> 47 #include <dirent.h> 48 #include <unistd.h> 49 #include <pwd.h> 50 #include <stdlib.h> 51 #include <limits.h> 52 53 /* 54 * Routines to expand arguments to commands. We have to deal with 55 * backquotes, shell variables, and file metacharacters. 56 */ 57 58 #include "shell.h" 59 #include "main.h" 60 #include "nodes.h" 61 #include "eval.h" 62 #include "expand.h" 63 #include "syntax.h" 64 #include "parser.h" 65 #include "jobs.h" 66 #include "options.h" 67 #include "var.h" 68 #include "input.h" 69 #include "output.h" 70 #include "memalloc.h" 71 #include "error.h" 72 #include "mystring.h" 73 #include "arith.h" 74 #include "show.h" 75 76 /* 77 * Structure specifying which parts of the string should be searched 78 * for IFS characters. 79 */ 80 81 struct ifsregion { 82 struct ifsregion *next; /* next region in list */ 83 int begoff; /* offset of start of region */ 84 int endoff; /* offset of end of region */ 85 int nulonly; /* search for nul bytes only */ 86 }; 87 88 89 char *expdest; /* output of current string */ 90 struct nodelist *argbackq; /* list of back quote expressions */ 91 struct ifsregion ifsfirst; /* first struct in list of ifs regions */ 92 struct ifsregion *ifslastp; /* last struct in list */ 93 struct arglist exparg; /* holds expanded arg list */ 94 95 STATIC void argstr __P((char *, int)); 96 STATIC char *exptilde __P((char *, int)); 97 STATIC void expbackq __P((union node *, int, int)); 98 STATIC int subevalvar __P((char *, char *, int, int, int, int)); 99 STATIC char *evalvar __P((char *, int)); 100 STATIC int varisset __P((char *)); 101 STATIC void varvalue __P((char *, int, int)); 102 STATIC void recordregion __P((int, int, int)); 103 STATIC void ifsbreakup __P((char *, struct arglist *)); 104 STATIC void expandmeta __P((struct strlist *, int)); 105 STATIC void expmeta __P((char *, char *)); 106 STATIC void addfname __P((char *)); 107 STATIC struct strlist *expsort __P((struct strlist *)); 108 STATIC struct strlist *msort __P((struct strlist *, int)); 109 STATIC int pmatch __P((char *, char *)); 110 STATIC char *cvtnum __P((int, char *)); 111 STATIC int collate_range_cmp __P((int, int)); 112 113 STATIC int collate_range_cmp (c1, c2) 114 int c1, c2; 115 { 116 static char s1[2], s2[2]; 117 int ret; 118 119 c1 &= UCHAR_MAX; 120 c2 &= UCHAR_MAX; 121 if (c1 == c2) 122 return (0); 123 s1[0] = c1; 124 s2[0] = c2; 125 if ((ret = strcoll(s1, s2)) != 0) 126 return (ret); 127 return (c1 - c2); 128 } 129 130 /* 131 * Expand shell variables and backquotes inside a here document. 132 */ 133 134 void 135 expandhere(arg, fd) 136 union node *arg; /* the document */ 137 int fd; /* where to write the expanded version */ 138 { 139 herefd = fd; 140 expandarg(arg, (struct arglist *)NULL, 0); 141 xwrite(fd, stackblock(), expdest - stackblock()); 142 } 143 144 145 /* 146 * Perform variable substitution and command substitution on an argument, 147 * placing the resulting list of arguments in arglist. If EXP_FULL is true, 148 * perform splitting and file name expansion. When arglist is NULL, perform 149 * here document expansion. 150 */ 151 152 void 153 expandarg(arg, arglist, flag) 154 union node *arg; 155 struct arglist *arglist; 156 int flag; 157 { 158 struct strlist *sp; 159 char *p; 160 161 argbackq = arg->narg.backquote; 162 STARTSTACKSTR(expdest); 163 ifsfirst.next = NULL; 164 ifslastp = NULL; 165 argstr(arg->narg.text, flag); 166 if (arglist == NULL) { 167 return; /* here document expanded */ 168 } 169 STPUTC('\0', expdest); 170 p = grabstackstr(expdest); 171 exparg.lastp = &exparg.list; 172 /* 173 * TODO - EXP_REDIR 174 */ 175 if (flag & EXP_FULL) { 176 ifsbreakup(p, &exparg); 177 *exparg.lastp = NULL; 178 exparg.lastp = &exparg.list; 179 expandmeta(exparg.list, flag); 180 } else { 181 if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */ 182 rmescapes(p); 183 sp = (struct strlist *)stalloc(sizeof (struct strlist)); 184 sp->text = p; 185 *exparg.lastp = sp; 186 exparg.lastp = &sp->next; 187 } 188 while (ifsfirst.next != NULL) { 189 struct ifsregion *ifsp; 190 INTOFF; 191 ifsp = ifsfirst.next->next; 192 ckfree(ifsfirst.next); 193 ifsfirst.next = ifsp; 194 INTON; 195 } 196 *exparg.lastp = NULL; 197 if (exparg.list) { 198 *arglist->lastp = exparg.list; 199 arglist->lastp = exparg.lastp; 200 } 201 } 202 203 204 205 /* 206 * Perform variable and command substitution. If EXP_FULL is set, output CTLESC 207 * characters to allow for further processing. Otherwise treat 208 * $@ like $* since no splitting will be performed. 209 */ 210 211 STATIC void 212 argstr(p, flag) 213 register char *p; 214 int flag; 215 { 216 register char c; 217 int quotes = flag & (EXP_FULL | EXP_CASE); /* do CTLESC */ 218 int firsteq = 1; 219 220 if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE))) 221 p = exptilde(p, flag); 222 for (;;) { 223 switch (c = *p++) { 224 case '\0': 225 case CTLENDVAR: /* ??? */ 226 goto breakloop; 227 case CTLESC: 228 if (quotes) 229 STPUTC(c, expdest); 230 c = *p++; 231 STPUTC(c, expdest); 232 break; 233 case CTLVAR: 234 p = evalvar(p, flag); 235 break; 236 case CTLBACKQ: 237 case CTLBACKQ|CTLQUOTE: 238 expbackq(argbackq->n, c & CTLQUOTE, flag); 239 argbackq = argbackq->next; 240 break; 241 case CTLENDARI: 242 expari(flag); 243 break; 244 case ':': 245 case '=': 246 /* 247 * sort of a hack - expand tildes in variable 248 * assignments (after the first '=' and after ':'s). 249 */ 250 STPUTC(c, expdest); 251 if (flag & EXP_VARTILDE && *p == '~') { 252 if (c == '=') { 253 if (firsteq) 254 firsteq = 0; 255 else 256 break; 257 } 258 p = exptilde(p, flag); 259 } 260 break; 261 default: 262 STPUTC(c, expdest); 263 } 264 } 265 breakloop:; 266 } 267 268 STATIC char * 269 exptilde(p, flag) 270 char *p; 271 int flag; 272 { 273 char c, *startp = p; 274 struct passwd *pw; 275 char *home; 276 int quotes = flag & (EXP_FULL | EXP_CASE); 277 278 while ((c = *p) != '\0') { 279 switch(c) { 280 case CTLESC: 281 return (startp); 282 case ':': 283 if (flag & EXP_VARTILDE) 284 goto done; 285 break; 286 case '/': 287 goto done; 288 } 289 p++; 290 } 291 done: 292 *p = '\0'; 293 if (*(startp+1) == '\0') { 294 if ((home = lookupvar("HOME")) == NULL) 295 goto lose; 296 } else { 297 if ((pw = getpwnam(startp+1)) == NULL) 298 goto lose; 299 home = pw->pw_dir; 300 } 301 if (*home == '\0') 302 goto lose; 303 *p = c; 304 while ((c = *home++) != '\0') { 305 if (quotes && SQSYNTAX[c] == CCTL) 306 STPUTC(CTLESC, expdest); 307 STPUTC(c, expdest); 308 } 309 return (p); 310 lose: 311 *p = c; 312 return (startp); 313 } 314 315 316 /* 317 * Expand arithmetic expression. Backup to start of expression, 318 * evaluate, place result in (backed up) result, adjust string position. 319 */ 320 void 321 expari(flag) 322 int flag; 323 { 324 char *p, *start; 325 int result; 326 int quotes = flag & (EXP_FULL | EXP_CASE); 327 328 /* 329 * This routine is slightly over-compilcated for 330 * efficiency. First we make sure there is 331 * enough space for the result, which may be bigger 332 * than the expression if we add exponentation. Next we 333 * scan backwards looking for the start of arithmetic. If the 334 * next previous character is a CTLESC character, then we 335 * have to rescan starting from the beginning since CTLESC 336 * characters have to be processed left to right. 337 */ 338 CHECKSTRSPACE(8, expdest); 339 USTPUTC('\0', expdest); 340 start = stackblock(); 341 p = expdest; 342 while (*p != CTLARI && p >= start) 343 --p; 344 if (*p != CTLARI) 345 error("missing CTLARI (shouldn't happen)"); 346 if (p > start && *(p-1) == CTLESC) 347 for (p = start; *p != CTLARI; p++) 348 if (*p == CTLESC) 349 p++; 350 if (quotes) 351 rmescapes(p+1); 352 result = arith(p+1); 353 fmtstr(p, 10, "%d", result); 354 while (*p++) 355 ; 356 result = expdest - p + 1; 357 STADJUST(-result, expdest); 358 } 359 360 361 /* 362 * Expand stuff in backwards quotes. 363 */ 364 365 STATIC void 366 expbackq(cmd, quoted, flag) 367 union node *cmd; 368 int quoted; 369 int flag; 370 { 371 struct backcmd in; 372 int i; 373 char buf[128]; 374 char *p; 375 char *dest = expdest; 376 struct ifsregion saveifs, *savelastp; 377 struct nodelist *saveargbackq; 378 char lastc; 379 int startloc = dest - stackblock(); 380 char const *syntax = quoted? DQSYNTAX : BASESYNTAX; 381 int saveherefd; 382 int quotes = flag & (EXP_FULL | EXP_CASE); 383 384 INTOFF; 385 saveifs = ifsfirst; 386 savelastp = ifslastp; 387 saveargbackq = argbackq; 388 saveherefd = herefd; 389 herefd = -1; 390 p = grabstackstr(dest); 391 evalbackcmd(cmd, &in); 392 ungrabstackstr(p, dest); 393 ifsfirst = saveifs; 394 ifslastp = savelastp; 395 argbackq = saveargbackq; 396 herefd = saveherefd; 397 398 p = in.buf; 399 lastc = '\0'; 400 for (;;) { 401 if (--in.nleft < 0) { 402 if (in.fd < 0) 403 break; 404 while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR); 405 TRACE(("expbackq: read returns %d\n", i)); 406 if (i <= 0) 407 break; 408 p = buf; 409 in.nleft = i - 1; 410 } 411 lastc = *p++; 412 if (lastc != '\0') { 413 if (quotes && syntax[lastc] == CCTL) 414 STPUTC(CTLESC, dest); 415 STPUTC(lastc, dest); 416 } 417 } 418 419 /* Eat all trailing newlines */ 420 for (p--; lastc == '\n'; lastc = *--p) 421 STUNPUTC(dest); 422 423 if (in.fd >= 0) 424 close(in.fd); 425 if (in.buf) 426 ckfree(in.buf); 427 if (in.jp) 428 exitstatus = waitforjob(in.jp); 429 if (quoted == 0) 430 recordregion(startloc, dest - stackblock(), 0); 431 TRACE(("evalbackq: size=%d: \"%.*s\"\n", 432 (dest - stackblock()) - startloc, 433 (dest - stackblock()) - startloc, 434 stackblock() + startloc)); 435 expdest = dest; 436 INTON; 437 } 438 439 440 441 STATIC int 442 subevalvar(p, str, strloc, subtype, startloc, varflags) 443 char *p; 444 char *str; 445 int strloc; 446 int subtype; 447 int startloc; 448 int varflags; 449 { 450 char *startp; 451 char *loc = NULL; 452 int c = 0; 453 int saveherefd = herefd; 454 struct nodelist *saveargbackq = argbackq; 455 int amount; 456 457 herefd = -1; 458 argstr(p, 0); 459 STACKSTRNUL(expdest); 460 herefd = saveherefd; 461 argbackq = saveargbackq; 462 startp = stackblock() + startloc; 463 if (str == NULL) 464 str = stackblock() + strloc; 465 466 switch (subtype) { 467 case VSASSIGN: 468 setvar(str, startp, 0); 469 amount = startp - expdest; 470 STADJUST(amount, expdest); 471 varflags &= ~VSNUL; 472 if (c != 0) 473 *loc = c; 474 return 1; 475 476 case VSQUESTION: 477 if (*p != CTLENDVAR) { 478 outfmt(&errout, "%s\n", startp); 479 error((char *)NULL); 480 } 481 error("%.*s: parameter %snot set", p - str - 1, 482 str, (varflags & VSNUL) ? "null or " 483 : nullstr); 484 return 0; 485 486 case VSTRIMLEFT: 487 for (loc = startp; loc < str - 1; loc++) { 488 c = *loc; 489 *loc = '\0'; 490 if (patmatch(str, startp)) { 491 *loc = c; 492 goto recordleft; 493 } 494 *loc = c; 495 } 496 return 0; 497 498 case VSTRIMLEFTMAX: 499 for (loc = str - 1; loc >= startp; loc--) { 500 c = *loc; 501 *loc = '\0'; 502 if (patmatch(str, startp)) { 503 *loc = c; 504 goto recordleft; 505 } 506 *loc = c; 507 } 508 return 0; 509 510 case VSTRIMRIGHT: 511 for (loc = str - 1; loc >= startp; loc--) { 512 if (patmatch(str, loc)) { 513 amount = loc - expdest; 514 STADJUST(amount, expdest); 515 return 1; 516 } 517 } 518 return 0; 519 520 case VSTRIMRIGHTMAX: 521 for (loc = startp; loc < str - 1; loc++) { 522 if (patmatch(str, loc)) { 523 amount = loc - expdest; 524 STADJUST(amount, expdest); 525 return 1; 526 } 527 } 528 return 0; 529 530 531 default: 532 abort(); 533 } 534 535 recordleft: 536 amount = ((str - 1) - (loc - startp)) - expdest; 537 STADJUST(amount, expdest); 538 while (loc != str - 1) 539 *startp++ = *loc++; 540 return 1; 541 } 542 543 544 /* 545 * Expand a variable, and return a pointer to the next character in the 546 * input string. 547 */ 548 549 STATIC char * 550 evalvar(p, flag) 551 char *p; 552 int flag; 553 { 554 int subtype; 555 int varflags; 556 char *var; 557 char *val; 558 char *pat; 559 int c; 560 int set; 561 int special; 562 int startloc; 563 int varlen; 564 int easy; 565 int quotes = flag & (EXP_FULL | EXP_CASE); 566 567 varflags = *p++; 568 subtype = varflags & VSTYPE; 569 var = p; 570 special = 0; 571 if (! is_name(*p)) 572 special = 1; 573 p = strchr(p, '=') + 1; 574 again: /* jump here after setting a variable with ${var=text} */ 575 if (special) { 576 set = varisset(var); 577 val = NULL; 578 } else { 579 val = lookupvar(var); 580 if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) { 581 val = NULL; 582 set = 0; 583 } else 584 set = 1; 585 } 586 varlen = 0; 587 startloc = expdest - stackblock(); 588 if (set && subtype != VSPLUS) { 589 /* insert the value of the variable */ 590 if (special) { 591 char *exp, *oexpdest = expdest; 592 varvalue(var, varflags & VSQUOTE, flag & EXP_FULL); 593 if (subtype == VSLENGTH) { 594 for (exp = oexpdest;exp != expdest; exp++) 595 varlen++; 596 expdest = oexpdest; 597 } 598 } else { 599 char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX 600 : BASESYNTAX; 601 602 if (subtype == VSLENGTH) { 603 for (;*val; val++) 604 varlen++; 605 } 606 else { 607 while (*val) { 608 if (quotes && syntax[*val] == CCTL) 609 STPUTC(CTLESC, expdest); 610 STPUTC(*val++, expdest); 611 } 612 613 } 614 } 615 } 616 617 if (subtype == VSPLUS) 618 set = ! set; 619 620 easy = ((varflags & VSQUOTE) == 0 || 621 (*var == '@' && shellparam.nparam != 1)); 622 623 624 switch (subtype) { 625 case VSLENGTH: 626 expdest = cvtnum(varlen, expdest); 627 goto record; 628 629 case VSNORMAL: 630 if (!easy) 631 break; 632 record: 633 recordregion(startloc, expdest - stackblock(), 634 varflags & VSQUOTE); 635 break; 636 637 case VSPLUS: 638 case VSMINUS: 639 if (!set) { 640 argstr(p, flag); 641 break; 642 } 643 if (easy) 644 goto record; 645 break; 646 647 case VSTRIMLEFT: 648 case VSTRIMLEFTMAX: 649 case VSTRIMRIGHT: 650 case VSTRIMRIGHTMAX: 651 if (!set) 652 break; 653 /* 654 * Terminate the string and start recording the pattern 655 * right after it 656 */ 657 STPUTC('\0', expdest); 658 pat = expdest; 659 if (subevalvar(p, NULL, expdest - stackblock(), subtype, 660 startloc, varflags)) 661 goto record; 662 break; 663 664 case VSASSIGN: 665 case VSQUESTION: 666 if (!set) { 667 if (subevalvar(p, var, 0, subtype, startloc, varflags)) { 668 varflags &= ~VSNUL; 669 goto again; 670 } 671 break; 672 } 673 if (easy) 674 goto record; 675 break; 676 677 default: 678 abort(); 679 } 680 681 if (subtype != VSNORMAL) { /* skip to end of alternative */ 682 int nesting = 1; 683 for (;;) { 684 if ((c = *p++) == CTLESC) 685 p++; 686 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { 687 if (set) 688 argbackq = argbackq->next; 689 } else if (c == CTLVAR) { 690 if ((*p++ & VSTYPE) != VSNORMAL) 691 nesting++; 692 } else if (c == CTLENDVAR) { 693 if (--nesting == 0) 694 break; 695 } 696 } 697 } 698 return p; 699 } 700 701 702 703 /* 704 * Test whether a specialized variable is set. 705 */ 706 707 STATIC int 708 varisset(name) 709 char *name; 710 { 711 char **ap; 712 713 if (*name == '!') { 714 if (backgndpid == -1) 715 return 0; 716 } else if (*name == '@' || *name == '*') { 717 if (*shellparam.p == NULL) 718 return 0; 719 } else if (is_digit(*name)) { 720 int num = atoi(name); 721 ap = shellparam.p; 722 while (--num >= 0) 723 if (*ap++ == NULL) 724 return 0; 725 } 726 return 1; 727 } 728 729 730 731 /* 732 * Add the value of a specialized variable to the stack string. 733 */ 734 735 STATIC void 736 varvalue(name, quoted, allow_split) 737 char *name; 738 int quoted; 739 int allow_split; 740 { 741 int num; 742 char *p; 743 int i; 744 extern int oexitstatus; 745 char sep; 746 char **ap; 747 char const *syntax; 748 749 #define STRTODEST(p) \ 750 do {\ 751 if (allow_split) { \ 752 syntax = quoted? DQSYNTAX : BASESYNTAX; \ 753 while (*p) { \ 754 if (syntax[*p] == CCTL) \ 755 STPUTC(CTLESC, expdest); \ 756 STPUTC(*p++, expdest); \ 757 } \ 758 } else \ 759 while (*p) \ 760 STPUTC(*p++, expdest); \ 761 } while (0) 762 763 764 switch (*name) { 765 case '$': 766 num = rootpid; 767 goto numvar; 768 case '?': 769 num = oexitstatus; 770 goto numvar; 771 case '#': 772 num = shellparam.nparam; 773 goto numvar; 774 case '!': 775 num = backgndpid; 776 numvar: 777 expdest = cvtnum(num, expdest); 778 break; 779 case '-': 780 for (i = 0 ; i < NOPTS ; i++) { 781 if (optlist[i].val) 782 STPUTC(optlist[i].letter, expdest); 783 } 784 break; 785 case '@': 786 if (allow_split) { 787 sep = '\0'; 788 goto allargs; 789 } 790 /* fall through */ 791 case '*': 792 sep = ' '; 793 allargs: 794 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 795 STRTODEST(p); 796 if (*ap) 797 STPUTC(sep, expdest); 798 } 799 break; 800 case '0': 801 p = arg0; 802 STRTODEST(p); 803 break; 804 default: 805 if (is_digit(*name)) { 806 num = atoi(name); 807 if (num > 0 && num <= shellparam.nparam) { 808 p = shellparam.p[num - 1]; 809 STRTODEST(p); 810 } 811 } 812 break; 813 } 814 } 815 816 817 818 /* 819 * Record the the fact that we have to scan this region of the 820 * string for IFS characters. 821 */ 822 823 STATIC void 824 recordregion(start, end, nulonly) 825 int start; 826 int end; 827 int nulonly; 828 { 829 register struct ifsregion *ifsp; 830 831 if (ifslastp == NULL) { 832 ifsp = &ifsfirst; 833 } else { 834 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 835 ifslastp->next = ifsp; 836 } 837 ifslastp = ifsp; 838 ifslastp->next = NULL; 839 ifslastp->begoff = start; 840 ifslastp->endoff = end; 841 ifslastp->nulonly = nulonly; 842 } 843 844 845 846 /* 847 * Break the argument string into pieces based upon IFS and add the 848 * strings to the argument list. The regions of the string to be 849 * searched for IFS characters have been stored by recordregion. 850 */ 851 STATIC void 852 ifsbreakup(string, arglist) 853 char *string; 854 struct arglist *arglist; 855 { 856 struct ifsregion *ifsp; 857 struct strlist *sp; 858 char *start; 859 register char *p; 860 char *q; 861 char *ifs; 862 int ifsspc; 863 864 865 start = string; 866 if (ifslastp != NULL) { 867 ifsp = &ifsfirst; 868 do { 869 p = string + ifsp->begoff; 870 ifs = ifsp->nulonly? nullstr : ifsval(); 871 ifsspc = strchr(ifs, ' ') != NULL; 872 while (p < string + ifsp->endoff) { 873 q = p; 874 if (*p == CTLESC) 875 p++; 876 if (strchr(ifs, *p++)) { 877 if (q > start || !ifsspc) { 878 *q = '\0'; 879 sp = (struct strlist *)stalloc(sizeof *sp); 880 sp->text = start; 881 *arglist->lastp = sp; 882 arglist->lastp = &sp->next; 883 } 884 if (ifsspc) { 885 for (;;) { 886 if (p >= string + ifsp->endoff) 887 break; 888 q = p; 889 if (*p == CTLESC) 890 p++; 891 if (strchr(ifs, *p++) == NULL) { 892 p = q; 893 break; 894 } 895 } 896 } 897 start = p; 898 } 899 } 900 } while ((ifsp = ifsp->next) != NULL); 901 if (*start || (!ifsspc && start > string)) { 902 sp = (struct strlist *)stalloc(sizeof *sp); 903 sp->text = start; 904 *arglist->lastp = sp; 905 arglist->lastp = &sp->next; 906 } 907 } else { 908 sp = (struct strlist *)stalloc(sizeof *sp); 909 sp->text = start; 910 *arglist->lastp = sp; 911 arglist->lastp = &sp->next; 912 } 913 } 914 915 916 917 /* 918 * Expand shell metacharacters. At this point, the only control characters 919 * should be escapes. The results are stored in the list exparg. 920 */ 921 922 char *expdir; 923 924 925 STATIC void 926 expandmeta(str, flag) 927 struct strlist *str; 928 int flag; 929 { 930 char *p; 931 struct strlist **savelastp; 932 struct strlist *sp; 933 char c; 934 /* TODO - EXP_REDIR */ 935 936 while (str) { 937 if (fflag) 938 goto nometa; 939 p = str->text; 940 for (;;) { /* fast check for meta chars */ 941 if ((c = *p++) == '\0') 942 goto nometa; 943 if (c == '*' || c == '?' || c == '[' || c == '!') 944 break; 945 } 946 savelastp = exparg.lastp; 947 INTOFF; 948 if (expdir == NULL) { 949 int i = strlen(str->text); 950 expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */ 951 } 952 953 expmeta(expdir, str->text); 954 ckfree(expdir); 955 expdir = NULL; 956 INTON; 957 if (exparg.lastp == savelastp) { 958 /* 959 * no matches 960 */ 961 nometa: 962 *exparg.lastp = str; 963 rmescapes(str->text); 964 exparg.lastp = &str->next; 965 } else { 966 *exparg.lastp = NULL; 967 *savelastp = sp = expsort(*savelastp); 968 while (sp->next != NULL) 969 sp = sp->next; 970 exparg.lastp = &sp->next; 971 } 972 str = str->next; 973 } 974 } 975 976 977 /* 978 * Do metacharacter (i.e. *, ?, [...]) expansion. 979 */ 980 981 STATIC void 982 expmeta(enddir, name) 983 char *enddir; 984 char *name; 985 { 986 register char *p; 987 char *q; 988 char *start; 989 char *endname; 990 int metaflag; 991 struct stat statb; 992 DIR *dirp; 993 struct dirent *dp; 994 int atend; 995 int matchdot; 996 997 metaflag = 0; 998 start = name; 999 for (p = name ; ; p++) { 1000 if (*p == '*' || *p == '?') 1001 metaflag = 1; 1002 else if (*p == '[') { 1003 q = p + 1; 1004 if (*q == '!') 1005 q++; 1006 for (;;) { 1007 if (*q == CTLESC) 1008 q++; 1009 if (*q == '/' || *q == '\0') 1010 break; 1011 if (*++q == ']') { 1012 metaflag = 1; 1013 break; 1014 } 1015 } 1016 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 1017 metaflag = 1; 1018 } else if (*p == '\0') 1019 break; 1020 else if (*p == CTLESC) 1021 p++; 1022 if (*p == '/') { 1023 if (metaflag) 1024 break; 1025 start = p + 1; 1026 } 1027 } 1028 if (metaflag == 0) { /* we've reached the end of the file name */ 1029 if (enddir != expdir) 1030 metaflag++; 1031 for (p = name ; ; p++) { 1032 if (*p == CTLESC) 1033 p++; 1034 *enddir++ = *p; 1035 if (*p == '\0') 1036 break; 1037 } 1038 if (metaflag == 0 || stat(expdir, &statb) >= 0) 1039 addfname(expdir); 1040 return; 1041 } 1042 endname = p; 1043 if (start != name) { 1044 p = name; 1045 while (p < start) { 1046 if (*p == CTLESC) 1047 p++; 1048 *enddir++ = *p++; 1049 } 1050 } 1051 if (enddir == expdir) { 1052 p = "."; 1053 } else if (enddir == expdir + 1 && *expdir == '/') { 1054 p = "/"; 1055 } else { 1056 p = expdir; 1057 enddir[-1] = '\0'; 1058 } 1059 if ((dirp = opendir(p)) == NULL) 1060 return; 1061 if (enddir != expdir) 1062 enddir[-1] = '/'; 1063 if (*endname == 0) { 1064 atend = 1; 1065 } else { 1066 atend = 0; 1067 *endname++ = '\0'; 1068 } 1069 matchdot = 0; 1070 if (start[0] == '.' || (start[0] == CTLESC && start[1] == '.')) 1071 matchdot++; 1072 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 1073 if (dp->d_name[0] == '.' && ! matchdot) 1074 continue; 1075 if (patmatch(start, dp->d_name)) { 1076 if (atend) { 1077 scopy(dp->d_name, enddir); 1078 addfname(expdir); 1079 } else { 1080 char *q; 1081 for (p = enddir, q = dp->d_name; 1082 (*p++ = *q++) != '\0';) 1083 continue; 1084 p[-1] = '/'; 1085 expmeta(p, endname); 1086 } 1087 } 1088 } 1089 closedir(dirp); 1090 if (! atend) 1091 endname[-1] = '/'; 1092 } 1093 1094 1095 /* 1096 * Add a file name to the list. 1097 */ 1098 1099 STATIC void 1100 addfname(name) 1101 char *name; 1102 { 1103 char *p; 1104 struct strlist *sp; 1105 1106 p = stalloc(strlen(name) + 1); 1107 scopy(name, p); 1108 sp = (struct strlist *)stalloc(sizeof *sp); 1109 sp->text = p; 1110 *exparg.lastp = sp; 1111 exparg.lastp = &sp->next; 1112 } 1113 1114 1115 /* 1116 * Sort the results of file name expansion. It calculates the number of 1117 * strings to sort and then calls msort (short for merge sort) to do the 1118 * work. 1119 */ 1120 1121 STATIC struct strlist * 1122 expsort(str) 1123 struct strlist *str; 1124 { 1125 int len; 1126 struct strlist *sp; 1127 1128 len = 0; 1129 for (sp = str ; sp ; sp = sp->next) 1130 len++; 1131 return msort(str, len); 1132 } 1133 1134 1135 STATIC struct strlist * 1136 msort(list, len) 1137 struct strlist *list; 1138 int len; 1139 { 1140 struct strlist *p, *q = NULL; 1141 struct strlist **lpp; 1142 int half; 1143 int n; 1144 1145 if (len <= 1) 1146 return list; 1147 half = len >> 1; 1148 p = list; 1149 for (n = half ; --n >= 0 ; ) { 1150 q = p; 1151 p = p->next; 1152 } 1153 q->next = NULL; /* terminate first half of list */ 1154 q = msort(list, half); /* sort first half of list */ 1155 p = msort(p, len - half); /* sort second half */ 1156 lpp = &list; 1157 for (;;) { 1158 if (strcmp(p->text, q->text) < 0) { 1159 *lpp = p; 1160 lpp = &p->next; 1161 if ((p = *lpp) == NULL) { 1162 *lpp = q; 1163 break; 1164 } 1165 } else { 1166 *lpp = q; 1167 lpp = &q->next; 1168 if ((q = *lpp) == NULL) { 1169 *lpp = p; 1170 break; 1171 } 1172 } 1173 } 1174 return list; 1175 } 1176 1177 1178 1179 /* 1180 * Returns true if the pattern matches the string. 1181 */ 1182 1183 int 1184 patmatch(pattern, string) 1185 char *pattern; 1186 char *string; 1187 { 1188 #ifdef notdef 1189 if (pattern[0] == '!' && pattern[1] == '!') 1190 return 1 - pmatch(pattern + 2, string); 1191 else 1192 #endif 1193 return pmatch(pattern, string); 1194 } 1195 1196 1197 STATIC int 1198 pmatch(pattern, string) 1199 char *pattern; 1200 char *string; 1201 { 1202 register char *p, *q; 1203 register char c; 1204 1205 p = pattern; 1206 q = string; 1207 for (;;) { 1208 switch (c = *p++) { 1209 case '\0': 1210 goto breakloop; 1211 case CTLESC: 1212 if (*q++ != *p++) 1213 return 0; 1214 break; 1215 case '?': 1216 if (*q++ == '\0') 1217 return 0; 1218 break; 1219 case '*': 1220 c = *p; 1221 if (c != CTLESC && c != '?' && c != '*' && c != '[') { 1222 while (*q != c) { 1223 if (*q == '\0') 1224 return 0; 1225 q++; 1226 } 1227 } 1228 do { 1229 if (pmatch(p, q)) 1230 return 1; 1231 } while (*q++ != '\0'); 1232 return 0; 1233 case '[': { 1234 char *endp; 1235 int invert, found; 1236 char chr; 1237 1238 endp = p; 1239 if (*endp == '!') 1240 endp++; 1241 for (;;) { 1242 if (*endp == '\0') 1243 goto dft; /* no matching ] */ 1244 if (*endp == CTLESC) 1245 endp++; 1246 if (*++endp == ']') 1247 break; 1248 } 1249 invert = 0; 1250 if (*p == '!') { 1251 invert++; 1252 p++; 1253 } 1254 found = 0; 1255 chr = *q++; 1256 if (chr == '\0') 1257 return 0; 1258 c = *p++; 1259 do { 1260 if (c == CTLESC) 1261 c = *p++; 1262 if (*p == '-' && p[1] != ']') { 1263 p++; 1264 if (*p == CTLESC) 1265 p++; 1266 if ( collate_range_cmp(chr, c) >= 0 1267 && collate_range_cmp(chr, *p) <= 0 1268 ) 1269 found = 1; 1270 p++; 1271 } else { 1272 if (chr == c) 1273 found = 1; 1274 } 1275 } while ((c = *p++) != ']'); 1276 if (found == invert) 1277 return 0; 1278 break; 1279 } 1280 dft: default: 1281 if (*q++ != c) 1282 return 0; 1283 break; 1284 } 1285 } 1286 breakloop: 1287 if (*q != '\0') 1288 return 0; 1289 return 1; 1290 } 1291 1292 1293 1294 /* 1295 * Remove any CTLESC characters from a string. 1296 */ 1297 1298 void 1299 rmescapes(str) 1300 char *str; 1301 { 1302 register char *p, *q; 1303 1304 p = str; 1305 while (*p != CTLESC) { 1306 if (*p++ == '\0') 1307 return; 1308 } 1309 q = p; 1310 while (*p) { 1311 if (*p == CTLESC) 1312 p++; 1313 *q++ = *p++; 1314 } 1315 *q = '\0'; 1316 } 1317 1318 1319 1320 /* 1321 * See if a pattern matches in a case statement. 1322 */ 1323 1324 int 1325 casematch(pattern, val) 1326 union node *pattern; 1327 char *val; 1328 { 1329 struct stackmark smark; 1330 int result; 1331 char *p; 1332 1333 setstackmark(&smark); 1334 argbackq = pattern->narg.backquote; 1335 STARTSTACKSTR(expdest); 1336 ifslastp = NULL; 1337 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); 1338 STPUTC('\0', expdest); 1339 p = grabstackstr(expdest); 1340 result = patmatch(p, val); 1341 popstackmark(&smark); 1342 return result; 1343 } 1344 1345 /* 1346 * Our own itoa(). 1347 */ 1348 1349 STATIC char * 1350 cvtnum(num, buf) 1351 int num; 1352 char *buf; 1353 { 1354 char temp[32]; 1355 int neg = num < 0; 1356 char *p = temp + 31; 1357 1358 temp[31] = '\0'; 1359 1360 do { 1361 *--p = num % 10 + '0'; 1362 } while ((num /= 10) != 0); 1363 1364 if (neg) 1365 *--p = '-'; 1366 1367 while (*p) 1368 STPUTC(*p++, buf); 1369 return buf; 1370 } 1371