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 * 4. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #ifndef lint 34 #if 0 35 static char sccsid[] = "@(#)expand.c 8.5 (Berkeley) 5/15/95"; 36 #endif 37 #endif /* not lint */ 38 #include <sys/cdefs.h> 39 __FBSDID("$FreeBSD$"); 40 41 #include <sys/types.h> 42 #include <sys/time.h> 43 #include <sys/stat.h> 44 #include <errno.h> 45 #include <dirent.h> 46 #include <unistd.h> 47 #include <pwd.h> 48 #include <stdlib.h> 49 #include <limits.h> 50 #include <stdio.h> 51 #include <string.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 STATIC char *expdest; /* output of current string */ 90 STATIC struct nodelist *argbackq; /* list of back quote expressions */ 91 STATIC struct ifsregion ifsfirst; /* first struct in list of ifs regions */ 92 STATIC struct ifsregion *ifslastp; /* last struct in list */ 93 STATIC struct arglist exparg; /* holds expanded arg list */ 94 95 STATIC void argstr(char *, int); 96 STATIC char *exptilde(char *, int); 97 STATIC void expbackq(union node *, int, int); 98 STATIC int subevalvar(char *, char *, int, int, int, int); 99 STATIC char *evalvar(char *, int); 100 STATIC int varisset(char *, int); 101 STATIC void varvalue(char *, int, int, int); 102 STATIC void recordregion(int, int, int); 103 STATIC void removerecordregions(int); 104 STATIC void ifsbreakup(char *, struct arglist *); 105 STATIC void expandmeta(struct strlist *, int); 106 STATIC void expmeta(char *, char *); 107 STATIC void addfname(char *); 108 STATIC struct strlist *expsort(struct strlist *); 109 STATIC struct strlist *msort(struct strlist *, int); 110 STATIC int pmatch(char *, char *, int); 111 STATIC char *cvtnum(int, char *); 112 STATIC int collate_range_cmp(int, int); 113 114 STATIC int 115 collate_range_cmp(int c1, int c2) 116 { 117 static char s1[2], s2[2]; 118 119 s1[0] = c1; 120 s2[0] = c2; 121 return (strcoll(s1, s2)); 122 } 123 124 /* 125 * Expand shell variables and backquotes inside a here document. 126 * union node *arg the document 127 * int fd; where to write the expanded version 128 */ 129 130 void 131 expandhere(union node *arg, int fd) 132 { 133 herefd = fd; 134 expandarg(arg, (struct arglist *)NULL, 0); 135 xwrite(fd, stackblock(), expdest - stackblock()); 136 } 137 138 139 /* 140 * Perform variable substitution and command substitution on an argument, 141 * placing the resulting list of arguments in arglist. If EXP_FULL is true, 142 * perform splitting and file name expansion. When arglist is NULL, perform 143 * here document expansion. 144 */ 145 146 void 147 expandarg(union node *arg, struct arglist *arglist, int flag) 148 { 149 struct strlist *sp; 150 char *p; 151 152 argbackq = arg->narg.backquote; 153 STARTSTACKSTR(expdest); 154 ifsfirst.next = NULL; 155 ifslastp = NULL; 156 argstr(arg->narg.text, flag); 157 if (arglist == NULL) { 158 return; /* here document expanded */ 159 } 160 STPUTC('\0', expdest); 161 p = grabstackstr(expdest); 162 exparg.lastp = &exparg.list; 163 /* 164 * TODO - EXP_REDIR 165 */ 166 if (flag & EXP_FULL) { 167 ifsbreakup(p, &exparg); 168 *exparg.lastp = NULL; 169 exparg.lastp = &exparg.list; 170 expandmeta(exparg.list, flag); 171 } else { 172 if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */ 173 rmescapes(p); 174 sp = (struct strlist *)stalloc(sizeof (struct strlist)); 175 sp->text = p; 176 *exparg.lastp = sp; 177 exparg.lastp = &sp->next; 178 } 179 while (ifsfirst.next != NULL) { 180 struct ifsregion *ifsp; 181 INTOFF; 182 ifsp = ifsfirst.next->next; 183 ckfree(ifsfirst.next); 184 ifsfirst.next = ifsp; 185 INTON; 186 } 187 *exparg.lastp = NULL; 188 if (exparg.list) { 189 *arglist->lastp = exparg.list; 190 arglist->lastp = exparg.lastp; 191 } 192 } 193 194 195 196 /* 197 * Perform variable and command substitution. If EXP_FULL is set, output CTLESC 198 * characters to allow for further processing. Otherwise treat 199 * $@ like $* since no splitting will be performed. 200 */ 201 202 STATIC void 203 argstr(char *p, int flag) 204 { 205 char c; 206 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); /* do CTLESC */ 207 int firsteq = 1; 208 209 if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE))) 210 p = exptilde(p, flag); 211 for (;;) { 212 switch (c = *p++) { 213 case '\0': 214 case CTLENDVAR: /* ??? */ 215 goto breakloop; 216 case CTLQUOTEMARK: 217 /* "$@" syntax adherence hack */ 218 if (p[0] == CTLVAR && p[2] == '@' && p[3] == '=') 219 break; 220 if ((flag & EXP_FULL) != 0) 221 STPUTC(c, expdest); 222 break; 223 case CTLESC: 224 if (quotes) 225 STPUTC(c, expdest); 226 c = *p++; 227 STPUTC(c, expdest); 228 break; 229 case CTLVAR: 230 p = evalvar(p, flag); 231 break; 232 case CTLBACKQ: 233 case CTLBACKQ|CTLQUOTE: 234 expbackq(argbackq->n, c & CTLQUOTE, flag); 235 argbackq = argbackq->next; 236 break; 237 case CTLENDARI: 238 expari(flag); 239 break; 240 case ':': 241 case '=': 242 /* 243 * sort of a hack - expand tildes in variable 244 * assignments (after the first '=' and after ':'s). 245 */ 246 STPUTC(c, expdest); 247 if (flag & EXP_VARTILDE && *p == '~') { 248 if (c == '=') { 249 if (firsteq) 250 firsteq = 0; 251 else 252 break; 253 } 254 p = exptilde(p, flag); 255 } 256 break; 257 default: 258 STPUTC(c, expdest); 259 } 260 } 261 breakloop:; 262 } 263 264 STATIC char * 265 exptilde(char *p, int flag) 266 { 267 char c, *startp = p; 268 struct passwd *pw; 269 char *home; 270 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 271 272 while ((c = *p) != '\0') { 273 switch(c) { 274 case CTLESC: 275 return (startp); 276 case CTLQUOTEMARK: 277 return (startp); 278 case ':': 279 if (flag & EXP_VARTILDE) 280 goto done; 281 break; 282 case '/': 283 goto done; 284 } 285 p++; 286 } 287 done: 288 *p = '\0'; 289 if (*(startp+1) == '\0') { 290 if ((home = lookupvar("HOME")) == NULL) 291 goto lose; 292 } else { 293 if ((pw = getpwnam(startp+1)) == NULL) 294 goto lose; 295 home = pw->pw_dir; 296 } 297 if (*home == '\0') 298 goto lose; 299 *p = c; 300 while ((c = *home++) != '\0') { 301 if (quotes && SQSYNTAX[(int)c] == CCTL) 302 STPUTC(CTLESC, expdest); 303 STPUTC(c, expdest); 304 } 305 return (p); 306 lose: 307 *p = c; 308 return (startp); 309 } 310 311 312 STATIC void 313 removerecordregions(int endoff) 314 { 315 if (ifslastp == NULL) 316 return; 317 318 if (ifsfirst.endoff > endoff) { 319 while (ifsfirst.next != NULL) { 320 struct ifsregion *ifsp; 321 INTOFF; 322 ifsp = ifsfirst.next->next; 323 ckfree(ifsfirst.next); 324 ifsfirst.next = ifsp; 325 INTON; 326 } 327 if (ifsfirst.begoff > endoff) 328 ifslastp = NULL; 329 else { 330 ifslastp = &ifsfirst; 331 ifsfirst.endoff = endoff; 332 } 333 return; 334 } 335 336 ifslastp = &ifsfirst; 337 while (ifslastp->next && ifslastp->next->begoff < endoff) 338 ifslastp=ifslastp->next; 339 while (ifslastp->next != NULL) { 340 struct ifsregion *ifsp; 341 INTOFF; 342 ifsp = ifslastp->next->next; 343 ckfree(ifslastp->next); 344 ifslastp->next = ifsp; 345 INTON; 346 } 347 if (ifslastp->endoff > endoff) 348 ifslastp->endoff = endoff; 349 } 350 351 /* 352 * Expand arithmetic expression. Backup to start of expression, 353 * evaluate, place result in (backed up) result, adjust string position. 354 */ 355 void 356 expari(int flag) 357 { 358 char *p, *start; 359 arith_t result; 360 int begoff; 361 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 362 int quoted; 363 364 365 /* 366 * This routine is slightly over-complicated for 367 * efficiency. First we make sure there is 368 * enough space for the result, which may be bigger 369 * than the expression if we add exponentiation. Next we 370 * scan backwards looking for the start of arithmetic. If the 371 * next previous character is a CTLESC character, then we 372 * have to rescan starting from the beginning since CTLESC 373 * characters have to be processed left to right. 374 */ 375 CHECKSTRSPACE(DIGITS(result) - 2, expdest); 376 USTPUTC('\0', expdest); 377 start = stackblock(); 378 p = expdest - 2; 379 while (p >= start && *p != CTLARI) 380 --p; 381 if (p < start || *p != CTLARI) 382 error("missing CTLARI (shouldn't happen)"); 383 if (p > start && *(p - 1) == CTLESC) 384 for (p = start; *p != CTLARI; p++) 385 if (*p == CTLESC) 386 p++; 387 388 if (p[1] == '"') 389 quoted=1; 390 else 391 quoted=0; 392 begoff = p - start; 393 removerecordregions(begoff); 394 if (quotes) 395 rmescapes(p+2); 396 result = arith(p+2); 397 fmtstr(p, DIGITS(result), ARITH_FORMAT_STR, result); 398 while (*p++) 399 ; 400 if (quoted == 0) 401 recordregion(begoff, p - 1 - start, 0); 402 result = expdest - p + 1; 403 STADJUST(-result, expdest); 404 } 405 406 407 /* 408 * Expand stuff in backwards quotes. 409 */ 410 411 STATIC void 412 expbackq(union node *cmd, int quoted, int flag) 413 { 414 struct backcmd in; 415 int i; 416 char buf[128]; 417 char *p; 418 char *dest = expdest; 419 struct ifsregion saveifs, *savelastp; 420 struct nodelist *saveargbackq; 421 char lastc; 422 int startloc = dest - stackblock(); 423 char const *syntax = quoted? DQSYNTAX : BASESYNTAX; 424 int saveherefd; 425 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 426 int nnl; 427 428 INTOFF; 429 saveifs = ifsfirst; 430 savelastp = ifslastp; 431 saveargbackq = argbackq; 432 saveherefd = herefd; 433 herefd = -1; 434 p = grabstackstr(dest); 435 evalbackcmd(cmd, &in); 436 ungrabstackstr(p, dest); 437 ifsfirst = saveifs; 438 ifslastp = savelastp; 439 argbackq = saveargbackq; 440 herefd = saveherefd; 441 442 p = in.buf; 443 lastc = '\0'; 444 nnl = 0; 445 /* Don't copy trailing newlines */ 446 for (;;) { 447 if (--in.nleft < 0) { 448 if (in.fd < 0) 449 break; 450 while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR); 451 TRACE(("expbackq: read returns %d\n", i)); 452 if (i <= 0) 453 break; 454 p = buf; 455 in.nleft = i - 1; 456 } 457 lastc = *p++; 458 if (lastc != '\0') { 459 if (quotes && syntax[(int)lastc] == CCTL) 460 STPUTC(CTLESC, dest); 461 if (lastc == '\n') { 462 nnl++; 463 } else { 464 while (nnl > 0) { 465 nnl--; 466 STPUTC('\n', dest); 467 } 468 STPUTC(lastc, dest); 469 } 470 } 471 } 472 473 if (in.fd >= 0) 474 close(in.fd); 475 if (in.buf) 476 ckfree(in.buf); 477 if (in.jp) 478 exitstatus = waitforjob(in.jp, (int *)NULL); 479 if (quoted == 0) 480 recordregion(startloc, dest - stackblock(), 0); 481 TRACE(("evalbackq: size=%d: \"%.*s\"\n", 482 (dest - stackblock()) - startloc, 483 (dest - stackblock()) - startloc, 484 stackblock() + startloc)); 485 expdest = dest; 486 INTON; 487 } 488 489 490 491 STATIC int 492 subevalvar(char *p, char *str, int strloc, int subtype, int startloc, 493 int varflags) 494 { 495 char *startp; 496 char *loc = NULL; 497 char *q; 498 int c = 0; 499 int saveherefd = herefd; 500 struct nodelist *saveargbackq = argbackq; 501 int amount; 502 503 herefd = -1; 504 argstr(p, 0); 505 STACKSTRNUL(expdest); 506 herefd = saveherefd; 507 argbackq = saveargbackq; 508 startp = stackblock() + startloc; 509 if (str == NULL) 510 str = stackblock() + strloc; 511 512 switch (subtype) { 513 case VSASSIGN: 514 setvar(str, startp, 0); 515 amount = startp - expdest; 516 STADJUST(amount, expdest); 517 varflags &= ~VSNUL; 518 if (c != 0) 519 *loc = c; 520 return 1; 521 522 case VSQUESTION: 523 if (*p != CTLENDVAR) { 524 outfmt(&errout, "%s\n", startp); 525 error((char *)NULL); 526 } 527 error("%.*s: parameter %snot set", (int)(p - str - 1), 528 str, (varflags & VSNUL) ? "null or " 529 : nullstr); 530 return 0; 531 532 case VSTRIMLEFT: 533 for (loc = startp; loc < str; loc++) { 534 c = *loc; 535 *loc = '\0'; 536 if (patmatch(str, startp, varflags & VSQUOTE)) { 537 *loc = c; 538 goto recordleft; 539 } 540 *loc = c; 541 if ((varflags & VSQUOTE) && *loc == CTLESC) 542 loc++; 543 } 544 return 0; 545 546 case VSTRIMLEFTMAX: 547 for (loc = str - 1; loc >= startp;) { 548 c = *loc; 549 *loc = '\0'; 550 if (patmatch(str, startp, varflags & VSQUOTE)) { 551 *loc = c; 552 goto recordleft; 553 } 554 *loc = c; 555 loc--; 556 if ((varflags & VSQUOTE) && loc > startp && 557 *(loc - 1) == CTLESC) { 558 for (q = startp; q < loc; q++) 559 if (*q == CTLESC) 560 q++; 561 if (q > loc) 562 loc--; 563 } 564 } 565 return 0; 566 567 case VSTRIMRIGHT: 568 for (loc = str - 1; loc >= startp;) { 569 if (patmatch(str, loc, varflags & VSQUOTE)) { 570 amount = loc - expdest; 571 STADJUST(amount, expdest); 572 return 1; 573 } 574 loc--; 575 if ((varflags & VSQUOTE) && loc > startp && 576 *(loc - 1) == CTLESC) { 577 for (q = startp; q < loc; q++) 578 if (*q == CTLESC) 579 q++; 580 if (q > loc) 581 loc--; 582 } 583 } 584 return 0; 585 586 case VSTRIMRIGHTMAX: 587 for (loc = startp; loc < str - 1; loc++) { 588 if (patmatch(str, loc, varflags & VSQUOTE)) { 589 amount = loc - expdest; 590 STADJUST(amount, expdest); 591 return 1; 592 } 593 if ((varflags & VSQUOTE) && *loc == CTLESC) 594 loc++; 595 } 596 return 0; 597 598 599 default: 600 abort(); 601 } 602 603 recordleft: 604 amount = ((str - 1) - (loc - startp)) - expdest; 605 STADJUST(amount, expdest); 606 while (loc != str - 1) 607 *startp++ = *loc++; 608 return 1; 609 } 610 611 612 /* 613 * Expand a variable, and return a pointer to the next character in the 614 * input string. 615 */ 616 617 STATIC char * 618 evalvar(char *p, int flag) 619 { 620 int subtype; 621 int varflags; 622 char *var; 623 char *val; 624 int patloc; 625 int c; 626 int set; 627 int special; 628 int startloc; 629 int varlen; 630 int easy; 631 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 632 633 varflags = (unsigned char)*p++; 634 subtype = varflags & VSTYPE; 635 var = p; 636 special = 0; 637 if (! is_name(*p)) 638 special = 1; 639 p = strchr(p, '=') + 1; 640 again: /* jump here after setting a variable with ${var=text} */ 641 if (special) { 642 set = varisset(var, varflags & VSNUL); 643 val = NULL; 644 } else { 645 val = bltinlookup(var, 1); 646 if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) { 647 val = NULL; 648 set = 0; 649 } else 650 set = 1; 651 } 652 varlen = 0; 653 startloc = expdest - stackblock(); 654 if (!set && uflag) { 655 switch (subtype) { 656 case VSNORMAL: 657 case VSTRIMLEFT: 658 case VSTRIMLEFTMAX: 659 case VSTRIMRIGHT: 660 case VSTRIMRIGHTMAX: 661 case VSLENGTH: 662 error("%.*s: parameter not set", (int)(p - var - 1), 663 var); 664 } 665 } 666 if (set && subtype != VSPLUS) { 667 /* insert the value of the variable */ 668 if (special) { 669 varvalue(var, varflags & VSQUOTE, subtype, flag); 670 if (subtype == VSLENGTH) { 671 varlen = expdest - stackblock() - startloc; 672 STADJUST(-varlen, expdest); 673 } 674 } else { 675 char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX 676 : BASESYNTAX; 677 678 if (subtype == VSLENGTH) { 679 for (;*val; val++) 680 varlen++; 681 } 682 else { 683 while (*val) { 684 if (quotes && 685 syntax[(int)*val] == CCTL) 686 STPUTC(CTLESC, expdest); 687 STPUTC(*val++, expdest); 688 } 689 690 } 691 } 692 } 693 694 if (subtype == VSPLUS) 695 set = ! set; 696 697 easy = ((varflags & VSQUOTE) == 0 || 698 (*var == '@' && shellparam.nparam != 1)); 699 700 701 switch (subtype) { 702 case VSLENGTH: 703 expdest = cvtnum(varlen, expdest); 704 goto record; 705 706 case VSNORMAL: 707 if (!easy) 708 break; 709 record: 710 recordregion(startloc, expdest - stackblock(), 711 varflags & VSQUOTE); 712 break; 713 714 case VSPLUS: 715 case VSMINUS: 716 if (!set) { 717 argstr(p, flag); 718 break; 719 } 720 if (easy) 721 goto record; 722 break; 723 724 case VSTRIMLEFT: 725 case VSTRIMLEFTMAX: 726 case VSTRIMRIGHT: 727 case VSTRIMRIGHTMAX: 728 if (!set) 729 break; 730 /* 731 * Terminate the string and start recording the pattern 732 * right after it 733 */ 734 STPUTC('\0', expdest); 735 patloc = expdest - stackblock(); 736 if (subevalvar(p, NULL, patloc, subtype, 737 startloc, varflags) == 0) { 738 int amount = (expdest - stackblock() - patloc) + 1; 739 STADJUST(-amount, expdest); 740 } 741 /* Remove any recorded regions beyond start of variable */ 742 removerecordregions(startloc); 743 goto record; 744 745 case VSASSIGN: 746 case VSQUESTION: 747 if (!set) { 748 if (subevalvar(p, var, 0, subtype, startloc, varflags)) { 749 varflags &= ~VSNUL; 750 /* 751 * Remove any recorded regions beyond 752 * start of variable 753 */ 754 removerecordregions(startloc); 755 goto again; 756 } 757 break; 758 } 759 if (easy) 760 goto record; 761 break; 762 763 case VSERROR: 764 c = p - var - 1; 765 error("${%.*s%s}: Bad substitution", c, var, 766 (c > 0 && *p != CTLENDVAR) ? "..." : ""); 767 768 default: 769 abort(); 770 } 771 772 if (subtype != VSNORMAL) { /* skip to end of alternative */ 773 int nesting = 1; 774 for (;;) { 775 if ((c = *p++) == CTLESC) 776 p++; 777 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { 778 if (set) 779 argbackq = argbackq->next; 780 } else if (c == CTLVAR) { 781 if ((*p++ & VSTYPE) != VSNORMAL) 782 nesting++; 783 } else if (c == CTLENDVAR) { 784 if (--nesting == 0) 785 break; 786 } 787 } 788 } 789 return p; 790 } 791 792 793 794 /* 795 * Test whether a specialized variable is set. 796 */ 797 798 STATIC int 799 varisset(char *name, int nulok) 800 { 801 802 if (*name == '!') 803 return backgndpid != -1; 804 else if (*name == '@' || *name == '*') { 805 if (*shellparam.p == NULL) 806 return 0; 807 808 if (nulok) { 809 char **av; 810 811 for (av = shellparam.p; *av; av++) 812 if (**av != '\0') 813 return 1; 814 return 0; 815 } 816 } else if (is_digit(*name)) { 817 char *ap; 818 int num = atoi(name); 819 820 if (num > shellparam.nparam) 821 return 0; 822 823 if (num == 0) 824 ap = arg0; 825 else 826 ap = shellparam.p[num - 1]; 827 828 if (nulok && (ap == NULL || *ap == '\0')) 829 return 0; 830 } 831 return 1; 832 } 833 834 835 836 /* 837 * Add the value of a specialized variable to the stack string. 838 */ 839 840 STATIC void 841 varvalue(char *name, int quoted, int subtype, int flag) 842 { 843 int num; 844 char *p; 845 int i; 846 extern int oexitstatus; 847 char sep; 848 char **ap; 849 char const *syntax; 850 851 #define STRTODEST(p) \ 852 do {\ 853 if (flag & (EXP_FULL | EXP_CASE) && subtype != VSLENGTH) { \ 854 syntax = quoted? DQSYNTAX : BASESYNTAX; \ 855 while (*p) { \ 856 if (syntax[(int)*p] == CCTL) \ 857 STPUTC(CTLESC, expdest); \ 858 STPUTC(*p++, expdest); \ 859 } \ 860 } else \ 861 while (*p) \ 862 STPUTC(*p++, expdest); \ 863 } while (0) 864 865 866 switch (*name) { 867 case '$': 868 num = rootpid; 869 goto numvar; 870 case '?': 871 num = oexitstatus; 872 goto numvar; 873 case '#': 874 num = shellparam.nparam; 875 goto numvar; 876 case '!': 877 num = backgndpid; 878 numvar: 879 expdest = cvtnum(num, expdest); 880 break; 881 case '-': 882 for (i = 0 ; i < NOPTS ; i++) { 883 if (optlist[i].val) 884 STPUTC(optlist[i].letter, expdest); 885 } 886 break; 887 case '@': 888 if (flag & EXP_FULL && quoted) { 889 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 890 STRTODEST(p); 891 if (*ap) 892 STPUTC('\0', expdest); 893 } 894 break; 895 } 896 /* FALLTHROUGH */ 897 case '*': 898 if (ifsset()) 899 sep = ifsval()[0]; 900 else 901 sep = ' '; 902 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 903 STRTODEST(p); 904 if (*ap && sep) 905 STPUTC(sep, expdest); 906 } 907 break; 908 case '0': 909 p = arg0; 910 STRTODEST(p); 911 break; 912 default: 913 if (is_digit(*name)) { 914 num = atoi(name); 915 if (num > 0 && num <= shellparam.nparam) { 916 p = shellparam.p[num - 1]; 917 STRTODEST(p); 918 } 919 } 920 break; 921 } 922 } 923 924 925 926 /* 927 * Record the the fact that we have to scan this region of the 928 * string for IFS characters. 929 */ 930 931 STATIC void 932 recordregion(int start, int end, int nulonly) 933 { 934 struct ifsregion *ifsp; 935 936 if (ifslastp == NULL) { 937 ifsp = &ifsfirst; 938 } else { 939 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 940 ifslastp->next = ifsp; 941 } 942 ifslastp = ifsp; 943 ifslastp->next = NULL; 944 ifslastp->begoff = start; 945 ifslastp->endoff = end; 946 ifslastp->nulonly = nulonly; 947 } 948 949 950 951 /* 952 * Break the argument string into pieces based upon IFS and add the 953 * strings to the argument list. The regions of the string to be 954 * searched for IFS characters have been stored by recordregion. 955 */ 956 STATIC void 957 ifsbreakup(char *string, struct arglist *arglist) 958 { 959 struct ifsregion *ifsp; 960 struct strlist *sp; 961 char *start; 962 char *p; 963 char *q; 964 char *ifs; 965 int ifsspc; 966 int nulonly; 967 968 969 start = string; 970 ifsspc = 0; 971 nulonly = 0; 972 if (ifslastp != NULL) { 973 ifsp = &ifsfirst; 974 do { 975 p = string + ifsp->begoff; 976 nulonly = ifsp->nulonly; 977 ifs = nulonly ? nullstr : 978 ( ifsset() ? ifsval() : " \t\n" ); 979 ifsspc = 0; 980 while (p < string + ifsp->endoff) { 981 q = p; 982 if (*p == CTLESC) 983 p++; 984 if (strchr(ifs, *p)) { 985 if (!nulonly) 986 ifsspc = (strchr(" \t\n", *p) != NULL); 987 /* Ignore IFS whitespace at start */ 988 if (q == start && ifsspc) { 989 p++; 990 start = p; 991 continue; 992 } 993 *q = '\0'; 994 sp = (struct strlist *)stalloc(sizeof *sp); 995 sp->text = start; 996 *arglist->lastp = sp; 997 arglist->lastp = &sp->next; 998 p++; 999 if (!nulonly) { 1000 for (;;) { 1001 if (p >= string + ifsp->endoff) { 1002 break; 1003 } 1004 q = p; 1005 if (*p == CTLESC) 1006 p++; 1007 if (strchr(ifs, *p) == NULL ) { 1008 p = q; 1009 break; 1010 } else if (strchr(" \t\n",*p) == NULL) { 1011 if (ifsspc) { 1012 p++; 1013 ifsspc = 0; 1014 } else { 1015 p = q; 1016 break; 1017 } 1018 } else 1019 p++; 1020 } 1021 } 1022 start = p; 1023 } else 1024 p++; 1025 } 1026 } while ((ifsp = ifsp->next) != NULL); 1027 if (*start || (!ifsspc && start > string)) { 1028 sp = (struct strlist *)stalloc(sizeof *sp); 1029 sp->text = start; 1030 *arglist->lastp = sp; 1031 arglist->lastp = &sp->next; 1032 } 1033 } else { 1034 sp = (struct strlist *)stalloc(sizeof *sp); 1035 sp->text = start; 1036 *arglist->lastp = sp; 1037 arglist->lastp = &sp->next; 1038 } 1039 } 1040 1041 1042 1043 /* 1044 * Expand shell metacharacters. At this point, the only control characters 1045 * should be escapes. The results are stored in the list exparg. 1046 */ 1047 1048 STATIC char *expdir; 1049 1050 1051 STATIC void 1052 expandmeta(struct strlist *str, int flag __unused) 1053 { 1054 char *p; 1055 struct strlist **savelastp; 1056 struct strlist *sp; 1057 char c; 1058 /* TODO - EXP_REDIR */ 1059 1060 while (str) { 1061 if (fflag) 1062 goto nometa; 1063 p = str->text; 1064 for (;;) { /* fast check for meta chars */ 1065 if ((c = *p++) == '\0') 1066 goto nometa; 1067 if (c == '*' || c == '?' || c == '[' || c == '!') 1068 break; 1069 } 1070 savelastp = exparg.lastp; 1071 INTOFF; 1072 if (expdir == NULL) { 1073 int i = strlen(str->text); 1074 expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */ 1075 } 1076 1077 expmeta(expdir, str->text); 1078 ckfree(expdir); 1079 expdir = NULL; 1080 INTON; 1081 if (exparg.lastp == savelastp) { 1082 /* 1083 * no matches 1084 */ 1085 nometa: 1086 *exparg.lastp = str; 1087 rmescapes(str->text); 1088 exparg.lastp = &str->next; 1089 } else { 1090 *exparg.lastp = NULL; 1091 *savelastp = sp = expsort(*savelastp); 1092 while (sp->next != NULL) 1093 sp = sp->next; 1094 exparg.lastp = &sp->next; 1095 } 1096 str = str->next; 1097 } 1098 } 1099 1100 1101 /* 1102 * Do metacharacter (i.e. *, ?, [...]) expansion. 1103 */ 1104 1105 STATIC void 1106 expmeta(char *enddir, char *name) 1107 { 1108 char *p; 1109 char *q; 1110 char *start; 1111 char *endname; 1112 int metaflag; 1113 struct stat statb; 1114 DIR *dirp; 1115 struct dirent *dp; 1116 int atend; 1117 int matchdot; 1118 1119 metaflag = 0; 1120 start = name; 1121 for (p = name ; ; p++) { 1122 if (*p == '*' || *p == '?') 1123 metaflag = 1; 1124 else if (*p == '[') { 1125 q = p + 1; 1126 if (*q == '!' || *q == '^') 1127 q++; 1128 for (;;) { 1129 while (*q == CTLQUOTEMARK) 1130 q++; 1131 if (*q == CTLESC) 1132 q++; 1133 if (*q == '/' || *q == '\0') 1134 break; 1135 if (*++q == ']') { 1136 metaflag = 1; 1137 break; 1138 } 1139 } 1140 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 1141 metaflag = 1; 1142 } else if (*p == '\0') 1143 break; 1144 else if (*p == CTLQUOTEMARK) 1145 continue; 1146 else if (*p == CTLESC) 1147 p++; 1148 if (*p == '/') { 1149 if (metaflag) 1150 break; 1151 start = p + 1; 1152 } 1153 } 1154 if (metaflag == 0) { /* we've reached the end of the file name */ 1155 if (enddir != expdir) 1156 metaflag++; 1157 for (p = name ; ; p++) { 1158 if (*p == CTLQUOTEMARK) 1159 continue; 1160 if (*p == CTLESC) 1161 p++; 1162 *enddir++ = *p; 1163 if (*p == '\0') 1164 break; 1165 } 1166 if (metaflag == 0 || lstat(expdir, &statb) >= 0) 1167 addfname(expdir); 1168 return; 1169 } 1170 endname = p; 1171 if (start != name) { 1172 p = name; 1173 while (p < start) { 1174 while (*p == CTLQUOTEMARK) 1175 p++; 1176 if (*p == CTLESC) 1177 p++; 1178 *enddir++ = *p++; 1179 } 1180 } 1181 if (enddir == expdir) { 1182 p = "."; 1183 } else if (enddir == expdir + 1 && *expdir == '/') { 1184 p = "/"; 1185 } else { 1186 p = expdir; 1187 enddir[-1] = '\0'; 1188 } 1189 if ((dirp = opendir(p)) == NULL) 1190 return; 1191 if (enddir != expdir) 1192 enddir[-1] = '/'; 1193 if (*endname == 0) { 1194 atend = 1; 1195 } else { 1196 atend = 0; 1197 *endname++ = '\0'; 1198 } 1199 matchdot = 0; 1200 p = start; 1201 while (*p == CTLQUOTEMARK) 1202 p++; 1203 if (*p == CTLESC) 1204 p++; 1205 if (*p == '.') 1206 matchdot++; 1207 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 1208 if (dp->d_name[0] == '.' && ! matchdot) 1209 continue; 1210 if (patmatch(start, dp->d_name, 0)) { 1211 if (atend) { 1212 scopy(dp->d_name, enddir); 1213 addfname(expdir); 1214 } else { 1215 for (p = enddir, q = dp->d_name; 1216 (*p++ = *q++) != '\0';) 1217 continue; 1218 p[-1] = '/'; 1219 expmeta(p, endname); 1220 } 1221 } 1222 } 1223 closedir(dirp); 1224 if (! atend) 1225 endname[-1] = '/'; 1226 } 1227 1228 1229 /* 1230 * Add a file name to the list. 1231 */ 1232 1233 STATIC void 1234 addfname(char *name) 1235 { 1236 char *p; 1237 struct strlist *sp; 1238 1239 p = stalloc(strlen(name) + 1); 1240 scopy(name, p); 1241 sp = (struct strlist *)stalloc(sizeof *sp); 1242 sp->text = p; 1243 *exparg.lastp = sp; 1244 exparg.lastp = &sp->next; 1245 } 1246 1247 1248 /* 1249 * Sort the results of file name expansion. It calculates the number of 1250 * strings to sort and then calls msort (short for merge sort) to do the 1251 * work. 1252 */ 1253 1254 STATIC struct strlist * 1255 expsort(struct strlist *str) 1256 { 1257 int len; 1258 struct strlist *sp; 1259 1260 len = 0; 1261 for (sp = str ; sp ; sp = sp->next) 1262 len++; 1263 return msort(str, len); 1264 } 1265 1266 1267 STATIC struct strlist * 1268 msort(struct strlist *list, int len) 1269 { 1270 struct strlist *p, *q = NULL; 1271 struct strlist **lpp; 1272 int half; 1273 int n; 1274 1275 if (len <= 1) 1276 return list; 1277 half = len >> 1; 1278 p = list; 1279 for (n = half ; --n >= 0 ; ) { 1280 q = p; 1281 p = p->next; 1282 } 1283 q->next = NULL; /* terminate first half of list */ 1284 q = msort(list, half); /* sort first half of list */ 1285 p = msort(p, len - half); /* sort second half */ 1286 lpp = &list; 1287 for (;;) { 1288 if (strcmp(p->text, q->text) < 0) { 1289 *lpp = p; 1290 lpp = &p->next; 1291 if ((p = *lpp) == NULL) { 1292 *lpp = q; 1293 break; 1294 } 1295 } else { 1296 *lpp = q; 1297 lpp = &q->next; 1298 if ((q = *lpp) == NULL) { 1299 *lpp = p; 1300 break; 1301 } 1302 } 1303 } 1304 return list; 1305 } 1306 1307 1308 1309 /* 1310 * Returns true if the pattern matches the string. 1311 */ 1312 1313 int 1314 patmatch(char *pattern, char *string, int squoted) 1315 { 1316 #ifdef notdef 1317 if (pattern[0] == '!' && pattern[1] == '!') 1318 return 1 - pmatch(pattern + 2, string); 1319 else 1320 #endif 1321 return pmatch(pattern, string, squoted); 1322 } 1323 1324 1325 STATIC int 1326 pmatch(char *pattern, char *string, int squoted) 1327 { 1328 char *p, *q; 1329 char c; 1330 1331 p = pattern; 1332 q = string; 1333 for (;;) { 1334 switch (c = *p++) { 1335 case '\0': 1336 goto breakloop; 1337 case CTLESC: 1338 if (squoted && *q == CTLESC) 1339 q++; 1340 if (*q++ != *p++) 1341 return 0; 1342 break; 1343 case CTLQUOTEMARK: 1344 continue; 1345 case '?': 1346 if (squoted && *q == CTLESC) 1347 q++; 1348 if (*q++ == '\0') 1349 return 0; 1350 break; 1351 case '*': 1352 c = *p; 1353 while (c == CTLQUOTEMARK || c == '*') 1354 c = *++p; 1355 if (c != CTLESC && c != CTLQUOTEMARK && 1356 c != '?' && c != '*' && c != '[') { 1357 while (*q != c) { 1358 if (squoted && *q == CTLESC && 1359 q[1] == c) 1360 break; 1361 if (*q == '\0') 1362 return 0; 1363 if (squoted && *q == CTLESC) 1364 q++; 1365 q++; 1366 } 1367 } 1368 do { 1369 if (pmatch(p, q, squoted)) 1370 return 1; 1371 if (squoted && *q == CTLESC) 1372 q++; 1373 } while (*q++ != '\0'); 1374 return 0; 1375 case '[': { 1376 char *endp; 1377 int invert, found; 1378 char chr; 1379 1380 endp = p; 1381 if (*endp == '!' || *endp == '^') 1382 endp++; 1383 for (;;) { 1384 while (*endp == CTLQUOTEMARK) 1385 endp++; 1386 if (*endp == '\0') 1387 goto dft; /* no matching ] */ 1388 if (*endp == CTLESC) 1389 endp++; 1390 if (*++endp == ']') 1391 break; 1392 } 1393 invert = 0; 1394 if (*p == '!' || *p == '^') { 1395 invert++; 1396 p++; 1397 } 1398 found = 0; 1399 chr = *q++; 1400 if (squoted && chr == CTLESC) 1401 chr = *q++; 1402 if (chr == '\0') 1403 return 0; 1404 c = *p++; 1405 do { 1406 if (c == CTLQUOTEMARK) 1407 continue; 1408 if (c == CTLESC) 1409 c = *p++; 1410 if (*p == '-' && p[1] != ']') { 1411 p++; 1412 while (*p == CTLQUOTEMARK) 1413 p++; 1414 if (*p == CTLESC) 1415 p++; 1416 if ( collate_range_cmp(chr, c) >= 0 1417 && collate_range_cmp(chr, *p) <= 0 1418 ) 1419 found = 1; 1420 p++; 1421 } else { 1422 if (chr == c) 1423 found = 1; 1424 } 1425 } while ((c = *p++) != ']'); 1426 if (found == invert) 1427 return 0; 1428 break; 1429 } 1430 dft: default: 1431 if (squoted && *q == CTLESC) 1432 q++; 1433 if (*q++ != c) 1434 return 0; 1435 break; 1436 } 1437 } 1438 breakloop: 1439 if (*q != '\0') 1440 return 0; 1441 return 1; 1442 } 1443 1444 1445 1446 /* 1447 * Remove any CTLESC characters from a string. 1448 */ 1449 1450 void 1451 rmescapes(char *str) 1452 { 1453 char *p, *q; 1454 1455 p = str; 1456 while (*p != CTLESC && *p != CTLQUOTEMARK) { 1457 if (*p++ == '\0') 1458 return; 1459 } 1460 q = p; 1461 while (*p) { 1462 if (*p == CTLQUOTEMARK) { 1463 p++; 1464 continue; 1465 } 1466 if (*p == CTLESC) 1467 p++; 1468 *q++ = *p++; 1469 } 1470 *q = '\0'; 1471 } 1472 1473 1474 1475 /* 1476 * See if a pattern matches in a case statement. 1477 */ 1478 1479 int 1480 casematch(union node *pattern, char *val) 1481 { 1482 struct stackmark smark; 1483 int result; 1484 char *p; 1485 1486 setstackmark(&smark); 1487 argbackq = pattern->narg.backquote; 1488 STARTSTACKSTR(expdest); 1489 ifslastp = NULL; 1490 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); 1491 STPUTC('\0', expdest); 1492 p = grabstackstr(expdest); 1493 result = patmatch(p, val, 0); 1494 popstackmark(&smark); 1495 return result; 1496 } 1497 1498 /* 1499 * Our own itoa(). 1500 */ 1501 1502 STATIC char * 1503 cvtnum(int num, char *buf) 1504 { 1505 char temp[32]; 1506 int neg = num < 0; 1507 char *p = temp + 31; 1508 1509 temp[31] = '\0'; 1510 1511 do { 1512 *--p = num % 10 + '0'; 1513 } while ((num /= 10) != 0); 1514 1515 if (neg) 1516 *--p = '-'; 1517 1518 while (*p) 1519 STPUTC(*p++, buf); 1520 return buf; 1521 } 1522 1523 /* 1524 * Do most of the work for wordexp(3). 1525 */ 1526 1527 int 1528 wordexpcmd(int argc, char **argv) 1529 { 1530 size_t len; 1531 int i; 1532 1533 out1fmt("%08x", argc - 1); 1534 for (i = 1, len = 0; i < argc; i++) 1535 len += strlen(argv[i]); 1536 out1fmt("%08x", (int)len); 1537 for (i = 1; i < argc; i++) { 1538 out1str(argv[i]); 1539 out1c('\0'); 1540 } 1541 return (0); 1542 } 1543