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 * @(#)expand.c 8.5 (Berkeley) 5/15/95 37 * $FreeBSD: src/bin/sh/expand.c,v 1.51 2006/11/07 22:46:13 stefanf Exp $ 38 * $DragonFly: src/bin/sh/expand.c,v 1.9 2007/01/07 16:58:30 pavalos Exp $ 39 */ 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 extern int oexitstatus; 125 126 /* 127 * Expand shell variables and backquotes inside a here document. 128 * union node *arg the document 129 * int fd; where to write the expanded version 130 */ 131 132 void 133 expandhere(union node *arg, int fd) 134 { 135 herefd = fd; 136 expandarg(arg, NULL, 0); 137 xwrite(fd, stackblock(), expdest - stackblock()); 138 } 139 140 141 /* 142 * Perform variable substitution and command substitution on an argument, 143 * placing the resulting list of arguments in arglist. If EXP_FULL is true, 144 * perform splitting and file name expansion. When arglist is NULL, perform 145 * here document expansion. 146 */ 147 148 void 149 expandarg(union node *arg, struct arglist *arglist, 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 $* since no splitting will be performed. 202 */ 203 204 STATIC void 205 argstr(char *p, int flag) 206 { 207 char c; 208 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); /* do CTLESC */ 209 int firsteq = 1; 210 211 if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE))) 212 p = exptilde(p, flag); 213 for (;;) { 214 switch (c = *p++) { 215 case '\0': 216 case CTLENDVAR: /* ??? */ 217 goto breakloop; 218 case CTLQUOTEMARK: 219 /* "$@" syntax adherence hack */ 220 if (p[0] == CTLVAR && p[2] == '@' && p[3] == '=') 221 break; 222 if ((flag & EXP_FULL) != 0) 223 STPUTC(c, expdest); 224 break; 225 case CTLESC: 226 if (quotes) 227 STPUTC(c, expdest); 228 c = *p++; 229 STPUTC(c, expdest); 230 break; 231 case CTLVAR: 232 p = evalvar(p, flag); 233 break; 234 case CTLBACKQ: 235 case CTLBACKQ|CTLQUOTE: 236 expbackq(argbackq->n, c & CTLQUOTE, flag); 237 argbackq = argbackq->next; 238 break; 239 case CTLENDARI: 240 expari(flag); 241 break; 242 case ':': 243 case '=': 244 /* 245 * sort of a hack - expand tildes in variable 246 * assignments (after the first '=' and after ':'s). 247 */ 248 STPUTC(c, expdest); 249 if (flag & EXP_VARTILDE && *p == '~') { 250 if (c == '=') { 251 if (firsteq) 252 firsteq = 0; 253 else 254 break; 255 } 256 p = exptilde(p, flag); 257 } 258 break; 259 default: 260 STPUTC(c, expdest); 261 } 262 } 263 breakloop:; 264 } 265 266 STATIC char * 267 exptilde(char *p, int flag) 268 { 269 char c, *startp = p; 270 struct passwd *pw; 271 char *home; 272 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 273 274 while ((c = *p) != '\0') { 275 switch(c) { 276 case CTLESC: 277 return (startp); 278 case CTLQUOTEMARK: 279 return (startp); 280 case ':': 281 if (flag & EXP_VARTILDE) 282 goto done; 283 break; 284 case '/': 285 goto done; 286 } 287 p++; 288 } 289 done: 290 *p = '\0'; 291 if (*(startp+1) == '\0') { 292 if ((home = lookupvar("HOME")) == NULL) 293 goto lose; 294 } else { 295 if ((pw = getpwnam(startp+1)) == NULL) 296 goto lose; 297 home = pw->pw_dir; 298 } 299 if (*home == '\0') 300 goto lose; 301 *p = c; 302 while ((c = *home++) != '\0') { 303 if (quotes && SQSYNTAX[(int)c] == CCTL) 304 STPUTC(CTLESC, expdest); 305 STPUTC(c, expdest); 306 } 307 return (p); 308 lose: 309 *p = c; 310 return (startp); 311 } 312 313 314 STATIC void 315 removerecordregions(int endoff) 316 { 317 if (ifslastp == NULL) 318 return; 319 320 if (ifsfirst.endoff > endoff) { 321 while (ifsfirst.next != NULL) { 322 struct ifsregion *ifsp; 323 INTOFF; 324 ifsp = ifsfirst.next->next; 325 ckfree(ifsfirst.next); 326 ifsfirst.next = ifsp; 327 INTON; 328 } 329 if (ifsfirst.begoff > endoff) 330 ifslastp = NULL; 331 else { 332 ifslastp = &ifsfirst; 333 ifsfirst.endoff = endoff; 334 } 335 return; 336 } 337 338 ifslastp = &ifsfirst; 339 while (ifslastp->next && ifslastp->next->begoff < endoff) 340 ifslastp=ifslastp->next; 341 while (ifslastp->next != NULL) { 342 struct ifsregion *ifsp; 343 INTOFF; 344 ifsp = ifslastp->next->next; 345 ckfree(ifslastp->next); 346 ifslastp->next = ifsp; 347 INTON; 348 } 349 if (ifslastp->endoff > endoff) 350 ifslastp->endoff = endoff; 351 } 352 353 /* 354 * Expand arithmetic expression. Backup to start of expression, 355 * evaluate, place result in (backed up) result, adjust string position. 356 */ 357 void 358 expari(int flag) 359 { 360 char *p, *start; 361 int result; 362 int begoff; 363 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 364 int quoted; 365 366 367 /* 368 * This routine is slightly over-complicated for 369 * efficiency. First we make sure there is 370 * enough space for the result, which may be bigger 371 * than the expression if we add exponentiation. Next we 372 * scan backwards looking for the start of arithmetic. If the 373 * next previous character is a CTLESC character, then we 374 * have to rescan starting from the beginning since CTLESC 375 * characters have to be processed left to right. 376 */ 377 #if INT_MAX / 1000000000 >= 10 || INT_MIN / 1000000000 <= -10 378 #error "integers with more than 10 digits are not supported" 379 #endif 380 CHECKSTRSPACE(12 - 2, expdest); 381 USTPUTC('\0', expdest); 382 start = stackblock(); 383 p = expdest - 2; 384 while (p >= start && *p != CTLARI) 385 --p; 386 if (p < start || *p != CTLARI) 387 error("missing CTLARI (shouldn't happen)"); 388 if (p > start && *(p - 1) == CTLESC) 389 for (p = start; *p != CTLARI; p++) 390 if (*p == CTLESC) 391 p++; 392 393 if (p[1] == '"') 394 quoted=1; 395 else 396 quoted=0; 397 begoff = p - start; 398 removerecordregions(begoff); 399 if (quotes) 400 rmescapes(p+2); 401 result = arith(p+2); 402 fmtstr(p, 12, "%d", result); 403 while (*p++) 404 ; 405 if (quoted == 0) 406 recordregion(begoff, p - 1 - start, 0); 407 result = expdest - p + 1; 408 STADJUST(-result, expdest); 409 } 410 411 412 /* 413 * Expand stuff in backwards quotes. 414 */ 415 416 STATIC void 417 expbackq(union node *cmd, int quoted, int flag) 418 { 419 struct backcmd in; 420 int i; 421 char buf[128]; 422 char *p; 423 char *dest = expdest; 424 struct ifsregion saveifs, *savelastp; 425 struct nodelist *saveargbackq; 426 char lastc; 427 int startloc = dest - stackblock(); 428 char const *syntax = quoted? DQSYNTAX : BASESYNTAX; 429 int saveherefd; 430 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 431 int nnl; 432 433 INTOFF; 434 saveifs = ifsfirst; 435 savelastp = ifslastp; 436 saveargbackq = argbackq; 437 saveherefd = herefd; 438 herefd = -1; 439 p = grabstackstr(dest); 440 evalbackcmd(cmd, &in); 441 ungrabstackstr(p, dest); 442 ifsfirst = saveifs; 443 ifslastp = savelastp; 444 argbackq = saveargbackq; 445 herefd = saveherefd; 446 447 p = in.buf; 448 lastc = '\0'; 449 nnl = 0; 450 /* Don't copy trailing newlines */ 451 for (;;) { 452 if (--in.nleft < 0) { 453 if (in.fd < 0) 454 break; 455 while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR); 456 TRACE(("expbackq: read returns %d\n", i)); 457 if (i <= 0) 458 break; 459 p = buf; 460 in.nleft = i - 1; 461 } 462 lastc = *p++; 463 if (lastc != '\0') { 464 if (quotes && syntax[(int)lastc] == CCTL) 465 STPUTC(CTLESC, dest); 466 if (lastc == '\n') { 467 nnl++; 468 } else { 469 while (nnl > 0) { 470 nnl--; 471 STPUTC('\n', dest); 472 } 473 STPUTC(lastc, dest); 474 } 475 } 476 } 477 478 if (in.fd >= 0) 479 close(in.fd); 480 if (in.buf) 481 ckfree(in.buf); 482 if (in.jp) 483 exitstatus = waitforjob(in.jp, NULL); 484 if (quoted == 0) 485 recordregion(startloc, dest - stackblock(), 0); 486 TRACE(("evalbackq: size=%d: \"%.*s\"\n", 487 (dest - stackblock()) - startloc, 488 (dest - stackblock()) - startloc, 489 stackblock() + startloc)); 490 expdest = dest; 491 INTON; 492 } 493 494 495 496 STATIC int 497 subevalvar(char *p, char *str, int strloc, int subtype, int startloc, 498 int varflags) 499 { 500 char *startp; 501 char *loc = NULL; 502 char *q; 503 int c = 0; 504 int saveherefd = herefd; 505 struct nodelist *saveargbackq = argbackq; 506 int amount; 507 508 herefd = -1; 509 argstr(p, 0); 510 STACKSTRNUL(expdest); 511 herefd = saveherefd; 512 argbackq = saveargbackq; 513 startp = stackblock() + startloc; 514 if (str == NULL) 515 str = stackblock() + strloc; 516 517 switch (subtype) { 518 case VSASSIGN: 519 setvar(str, startp, 0); 520 amount = startp - expdest; 521 STADJUST(amount, expdest); 522 varflags &= ~VSNUL; 523 if (c != 0) 524 *loc = c; 525 return 1; 526 527 case VSQUESTION: 528 if (*p != CTLENDVAR) { 529 outfmt(&errout, "%s\n", startp); 530 error(NULL); 531 } 532 error("%.*s: parameter %snot set", (int)(p - str - 1), 533 str, (varflags & VSNUL) ? "null or " 534 : nullstr); 535 return 0; 536 537 case VSTRIMLEFT: 538 for (loc = startp; loc < str; loc++) { 539 c = *loc; 540 *loc = '\0'; 541 if (patmatch(str, startp, varflags & VSQUOTE)) { 542 *loc = c; 543 goto recordleft; 544 } 545 *loc = c; 546 if ((varflags & VSQUOTE) && *loc == CTLESC) 547 loc++; 548 } 549 return 0; 550 551 case VSTRIMLEFTMAX: 552 for (loc = str - 1; loc >= startp;) { 553 c = *loc; 554 *loc = '\0'; 555 if (patmatch(str, startp, varflags & VSQUOTE)) { 556 *loc = c; 557 goto recordleft; 558 } 559 *loc = c; 560 loc--; 561 if ((varflags & VSQUOTE) && loc > startp && 562 *(loc - 1) == CTLESC) { 563 for (q = startp; q < loc; q++) 564 if (*q == CTLESC) 565 q++; 566 if (q > loc) 567 loc--; 568 } 569 } 570 return 0; 571 572 case VSTRIMRIGHT: 573 for (loc = str - 1; loc >= startp;) { 574 if (patmatch(str, loc, varflags & VSQUOTE)) { 575 amount = loc - expdest; 576 STADJUST(amount, expdest); 577 return 1; 578 } 579 loc--; 580 if ((varflags & VSQUOTE) && loc > startp && 581 *(loc - 1) == CTLESC) { 582 for (q = startp; q < loc; q++) 583 if (*q == CTLESC) 584 q++; 585 if (q > loc) 586 loc--; 587 } 588 } 589 return 0; 590 591 case VSTRIMRIGHTMAX: 592 for (loc = startp; loc < str - 1; loc++) { 593 if (patmatch(str, loc, varflags & VSQUOTE)) { 594 amount = loc - expdest; 595 STADJUST(amount, expdest); 596 return 1; 597 } 598 if ((varflags & VSQUOTE) && *loc == CTLESC) 599 loc++; 600 } 601 return 0; 602 603 604 default: 605 abort(); 606 } 607 608 recordleft: 609 amount = ((str - 1) - (loc - startp)) - expdest; 610 STADJUST(amount, expdest); 611 while (loc != str - 1) 612 *startp++ = *loc++; 613 return 1; 614 } 615 616 617 /* 618 * Expand a variable, and return a pointer to the next character in the 619 * input string. 620 */ 621 622 STATIC char * 623 evalvar(char *p, int flag) 624 { 625 int subtype; 626 int varflags; 627 char *var; 628 char *val; 629 int patloc; 630 int c; 631 int set; 632 int special; 633 int startloc; 634 int varlen; 635 int easy; 636 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 637 638 varflags = (unsigned char)*p++; 639 subtype = varflags & VSTYPE; 640 var = p; 641 special = 0; 642 if (! is_name(*p)) 643 special = 1; 644 p = strchr(p, '=') + 1; 645 again: /* jump here after setting a variable with ${var=text} */ 646 if (varflags & VSLINENO) { 647 set = 1; 648 special = 0; 649 val = var; 650 p[-1] = '\0'; /* temporarily overwrite '=' to have \0 651 terminated string */ 652 } else if (special) { 653 set = varisset(var, varflags & VSNUL); 654 val = NULL; 655 } else { 656 val = bltinlookup(var, 1); 657 if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) { 658 val = NULL; 659 set = 0; 660 } else 661 set = 1; 662 } 663 varlen = 0; 664 startloc = expdest - stackblock(); 665 if (!set && uflag) { 666 switch (subtype) { 667 case VSNORMAL: 668 case VSTRIMLEFT: 669 case VSTRIMLEFTMAX: 670 case VSTRIMRIGHT: 671 case VSTRIMRIGHTMAX: 672 case VSLENGTH: 673 error("%.*s: parameter not set", (int)(p - var - 1), 674 var); 675 } 676 } 677 if (set && subtype != VSPLUS) { 678 /* insert the value of the variable */ 679 if (special) { 680 varvalue(var, varflags & VSQUOTE, subtype, flag); 681 if (subtype == VSLENGTH) { 682 varlen = expdest - stackblock() - startloc; 683 STADJUST(-varlen, expdest); 684 } 685 } else { 686 char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX 687 : BASESYNTAX; 688 689 if (subtype == VSLENGTH) { 690 for (;*val; val++) 691 varlen++; 692 } 693 else { 694 while (*val) { 695 if (quotes && 696 syntax[(int)*val] == CCTL) 697 STPUTC(CTLESC, expdest); 698 STPUTC(*val++, expdest); 699 } 700 701 } 702 } 703 } 704 705 if (subtype == VSPLUS) 706 set = ! set; 707 708 easy = ((varflags & VSQUOTE) == 0 || 709 (*var == '@' && shellparam.nparam != 1)); 710 711 712 switch (subtype) { 713 case VSLENGTH: 714 expdest = cvtnum(varlen, expdest); 715 goto record; 716 717 case VSNORMAL: 718 if (!easy) 719 break; 720 record: 721 recordregion(startloc, expdest - stackblock(), 722 varflags & VSQUOTE); 723 break; 724 725 case VSPLUS: 726 case VSMINUS: 727 if (!set) { 728 argstr(p, flag); 729 break; 730 } 731 if (easy) 732 goto record; 733 break; 734 735 case VSTRIMLEFT: 736 case VSTRIMLEFTMAX: 737 case VSTRIMRIGHT: 738 case VSTRIMRIGHTMAX: 739 if (!set) 740 break; 741 /* 742 * Terminate the string and start recording the pattern 743 * right after it 744 */ 745 STPUTC('\0', expdest); 746 patloc = expdest - stackblock(); 747 if (subevalvar(p, NULL, patloc, subtype, 748 startloc, varflags) == 0) { 749 int amount = (expdest - stackblock() - patloc) + 1; 750 STADJUST(-amount, expdest); 751 } 752 /* Remove any recorded regions beyond start of variable */ 753 removerecordregions(startloc); 754 goto record; 755 756 case VSASSIGN: 757 case VSQUESTION: 758 if (!set) { 759 if (subevalvar(p, var, 0, subtype, startloc, varflags)) { 760 varflags &= ~VSNUL; 761 /* 762 * Remove any recorded regions beyond 763 * start of variable 764 */ 765 removerecordregions(startloc); 766 goto again; 767 } 768 break; 769 } 770 if (easy) 771 goto record; 772 break; 773 774 case VSERROR: 775 c = p - var - 1; 776 error("${%.*s%s}: Bad substitution", c, var, 777 (c > 0 && *p != CTLENDVAR) ? "..." : ""); 778 779 default: 780 abort(); 781 } 782 p[-1] = '='; /* recover overwritten '=' */ 783 784 if (subtype != VSNORMAL) { /* skip to end of alternative */ 785 int nesting = 1; 786 for (;;) { 787 if ((c = *p++) == CTLESC) 788 p++; 789 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { 790 if (set) 791 argbackq = argbackq->next; 792 } else if (c == CTLVAR) { 793 if ((*p++ & VSTYPE) != VSNORMAL) 794 nesting++; 795 } else if (c == CTLENDVAR) { 796 if (--nesting == 0) 797 break; 798 } 799 } 800 } 801 return p; 802 } 803 804 805 806 /* 807 * Test whether a specialized variable is set. 808 */ 809 810 STATIC int 811 varisset(char *name, int nulok) 812 { 813 814 if (*name == '!') 815 return backgndpid != -1; 816 else if (*name == '@' || *name == '*') { 817 if (*shellparam.p == NULL) 818 return 0; 819 820 if (nulok) { 821 char **av; 822 823 for (av = shellparam.p; *av; av++) 824 if (**av != '\0') 825 return 1; 826 return 0; 827 } 828 } else if (is_digit(*name)) { 829 char *ap; 830 int num = atoi(name); 831 832 if (num > shellparam.nparam) 833 return 0; 834 835 if (num == 0) 836 ap = arg0; 837 else 838 ap = shellparam.p[num - 1]; 839 840 if (nulok && (ap == NULL || *ap == '\0')) 841 return 0; 842 } 843 return 1; 844 } 845 846 847 848 /* 849 * Add the value of a specialized variable to the stack string. 850 */ 851 852 STATIC void 853 varvalue(char *name, int quoted, int subtype, int flag) 854 { 855 int num; 856 char *p; 857 int i; 858 char sep; 859 char **ap; 860 char const *syntax; 861 862 #define STRTODEST(p) \ 863 do {\ 864 if (flag & (EXP_FULL | EXP_CASE) && subtype != VSLENGTH) { \ 865 syntax = quoted? DQSYNTAX : BASESYNTAX; \ 866 while (*p) { \ 867 if (syntax[(int)*p] == CCTL) \ 868 STPUTC(CTLESC, expdest); \ 869 STPUTC(*p++, expdest); \ 870 } \ 871 } else \ 872 while (*p) \ 873 STPUTC(*p++, expdest); \ 874 } while (0) 875 876 877 switch (*name) { 878 case '$': 879 num = rootpid; 880 goto numvar; 881 case '?': 882 num = oexitstatus; 883 goto numvar; 884 case '#': 885 num = shellparam.nparam; 886 goto numvar; 887 case '!': 888 num = backgndpid; 889 numvar: 890 expdest = cvtnum(num, expdest); 891 break; 892 case '-': 893 for (i = 0 ; i < NOPTS ; i++) { 894 if (optlist[i].val) 895 STPUTC(optlist[i].letter, expdest); 896 } 897 break; 898 case '@': 899 if (flag & EXP_FULL && quoted) { 900 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 901 STRTODEST(p); 902 if (*ap) 903 STPUTC('\0', expdest); 904 } 905 break; 906 } 907 /* FALLTHROUGH */ 908 case '*': 909 if (ifsset()) 910 sep = ifsval()[0]; 911 else 912 sep = ' '; 913 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 914 STRTODEST(p); 915 if (*ap && sep) 916 STPUTC(sep, expdest); 917 } 918 break; 919 case '0': 920 p = arg0; 921 STRTODEST(p); 922 break; 923 default: 924 if (is_digit(*name)) { 925 num = atoi(name); 926 if (num > 0 && num <= shellparam.nparam) { 927 p = shellparam.p[num - 1]; 928 STRTODEST(p); 929 } 930 } 931 break; 932 } 933 } 934 935 936 937 /* 938 * Record the the fact that we have to scan this region of the 939 * string for IFS characters. 940 */ 941 942 STATIC void 943 recordregion(int start, int end, int nulonly) 944 { 945 struct ifsregion *ifsp; 946 947 if (ifslastp == NULL) { 948 ifsp = &ifsfirst; 949 } else { 950 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 951 ifslastp->next = ifsp; 952 } 953 ifslastp = ifsp; 954 ifslastp->next = NULL; 955 ifslastp->begoff = start; 956 ifslastp->endoff = end; 957 ifslastp->nulonly = nulonly; 958 } 959 960 961 962 /* 963 * Break the argument string into pieces based upon IFS and add the 964 * strings to the argument list. The regions of the string to be 965 * searched for IFS characters have been stored by recordregion. 966 */ 967 STATIC void 968 ifsbreakup(char *string, struct arglist *arglist) 969 { 970 struct ifsregion *ifsp; 971 struct strlist *sp; 972 char *start; 973 char *p; 974 char *q; 975 const char *ifs; 976 int ifsspc; 977 int nulonly; 978 979 980 start = string; 981 ifsspc = 0; 982 nulonly = 0; 983 if (ifslastp != NULL) { 984 ifsp = &ifsfirst; 985 do { 986 p = string + ifsp->begoff; 987 nulonly = ifsp->nulonly; 988 ifs = nulonly ? nullstr : 989 ( ifsset() ? ifsval() : " \t\n" ); 990 ifsspc = 0; 991 while (p < string + ifsp->endoff) { 992 q = p; 993 if (*p == CTLESC) 994 p++; 995 if (strchr(ifs, *p)) { 996 if (!nulonly) 997 ifsspc = (strchr(" \t\n", *p) != NULL); 998 /* Ignore IFS whitespace at start */ 999 if (q == start && ifsspc) { 1000 p++; 1001 start = p; 1002 continue; 1003 } 1004 *q = '\0'; 1005 sp = (struct strlist *)stalloc(sizeof *sp); 1006 sp->text = start; 1007 *arglist->lastp = sp; 1008 arglist->lastp = &sp->next; 1009 p++; 1010 if (!nulonly) { 1011 for (;;) { 1012 if (p >= string + ifsp->endoff) { 1013 break; 1014 } 1015 q = p; 1016 if (*p == CTLESC) 1017 p++; 1018 if (strchr(ifs, *p) == NULL ) { 1019 p = q; 1020 break; 1021 } else if (strchr(" \t\n",*p) == NULL) { 1022 if (ifsspc) { 1023 p++; 1024 ifsspc = 0; 1025 } else { 1026 p = q; 1027 break; 1028 } 1029 } else 1030 p++; 1031 } 1032 } 1033 start = p; 1034 } else 1035 p++; 1036 } 1037 } while ((ifsp = ifsp->next) != NULL); 1038 if (*start || (!ifsspc && start > string)) { 1039 sp = (struct strlist *)stalloc(sizeof *sp); 1040 sp->text = start; 1041 *arglist->lastp = sp; 1042 arglist->lastp = &sp->next; 1043 } 1044 } else { 1045 sp = (struct strlist *)stalloc(sizeof *sp); 1046 sp->text = start; 1047 *arglist->lastp = sp; 1048 arglist->lastp = &sp->next; 1049 } 1050 } 1051 1052 1053 1054 /* 1055 * Expand shell metacharacters. At this point, the only control characters 1056 * should be escapes. The results are stored in the list exparg. 1057 */ 1058 1059 STATIC char *expdir; 1060 1061 1062 STATIC void 1063 expandmeta(struct strlist *str, int flag __unused) 1064 { 1065 char *p; 1066 struct strlist **savelastp; 1067 struct strlist *sp; 1068 char c; 1069 /* TODO - EXP_REDIR */ 1070 1071 while (str) { 1072 if (fflag) 1073 goto nometa; 1074 p = str->text; 1075 for (;;) { /* fast check for meta chars */ 1076 if ((c = *p++) == '\0') 1077 goto nometa; 1078 if (c == '*' || c == '?' || c == '[' || c == '!') 1079 break; 1080 } 1081 savelastp = exparg.lastp; 1082 INTOFF; 1083 if (expdir == NULL) { 1084 int i = strlen(str->text); 1085 expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */ 1086 } 1087 1088 expmeta(expdir, str->text); 1089 ckfree(expdir); 1090 expdir = NULL; 1091 INTON; 1092 if (exparg.lastp == savelastp) { 1093 /* 1094 * no matches 1095 */ 1096 nometa: 1097 *exparg.lastp = str; 1098 rmescapes(str->text); 1099 exparg.lastp = &str->next; 1100 } else { 1101 *exparg.lastp = NULL; 1102 *savelastp = sp = expsort(*savelastp); 1103 while (sp->next != NULL) 1104 sp = sp->next; 1105 exparg.lastp = &sp->next; 1106 } 1107 str = str->next; 1108 } 1109 } 1110 1111 1112 /* 1113 * Do metacharacter (i.e. *, ?, [...]) expansion. 1114 */ 1115 1116 STATIC void 1117 expmeta(char *enddir, char *name) 1118 { 1119 char *p; 1120 const char *q; 1121 char *start; 1122 char *endname; 1123 int metaflag; 1124 struct stat statb; 1125 DIR *dirp; 1126 struct dirent *dp; 1127 int atend; 1128 int matchdot; 1129 1130 metaflag = 0; 1131 start = name; 1132 for (p = name ; ; p++) { 1133 if (*p == '*' || *p == '?') 1134 metaflag = 1; 1135 else if (*p == '[') { 1136 q = p + 1; 1137 if (*q == '!' || *q == '^') 1138 q++; 1139 for (;;) { 1140 while (*q == CTLQUOTEMARK) 1141 q++; 1142 if (*q == CTLESC) 1143 q++; 1144 if (*q == '/' || *q == '\0') 1145 break; 1146 if (*++q == ']') { 1147 metaflag = 1; 1148 break; 1149 } 1150 } 1151 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 1152 metaflag = 1; 1153 } else if (*p == '\0') 1154 break; 1155 else if (*p == CTLQUOTEMARK) 1156 continue; 1157 else if (*p == CTLESC) 1158 p++; 1159 if (*p == '/') { 1160 if (metaflag) 1161 break; 1162 start = p + 1; 1163 } 1164 } 1165 if (metaflag == 0) { /* we've reached the end of the file name */ 1166 if (enddir != expdir) 1167 metaflag++; 1168 for (p = name ; ; p++) { 1169 if (*p == CTLQUOTEMARK) 1170 continue; 1171 if (*p == CTLESC) 1172 p++; 1173 *enddir++ = *p; 1174 if (*p == '\0') 1175 break; 1176 } 1177 if (metaflag == 0 || lstat(expdir, &statb) >= 0) 1178 addfname(expdir); 1179 return; 1180 } 1181 endname = p; 1182 if (start != name) { 1183 p = name; 1184 while (p < start) { 1185 while (*p == CTLQUOTEMARK) 1186 p++; 1187 if (*p == CTLESC) 1188 p++; 1189 *enddir++ = *p++; 1190 } 1191 } 1192 if (enddir == expdir) { 1193 q = "."; 1194 } else if (enddir == expdir + 1 && *expdir == '/') { 1195 q = "/"; 1196 } else { 1197 q = expdir; 1198 enddir[-1] = '\0'; 1199 } 1200 if ((dirp = opendir(q)) == NULL) 1201 return; 1202 if (enddir != expdir) 1203 enddir[-1] = '/'; 1204 if (*endname == 0) { 1205 atend = 1; 1206 } else { 1207 atend = 0; 1208 *endname++ = '\0'; 1209 } 1210 matchdot = 0; 1211 p = start; 1212 while (*p == CTLQUOTEMARK) 1213 p++; 1214 if (*p == CTLESC) 1215 p++; 1216 if (*p == '.') 1217 matchdot++; 1218 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 1219 if (dp->d_name[0] == '.' && ! matchdot) 1220 continue; 1221 if (patmatch(start, dp->d_name, 0)) { 1222 if (atend) { 1223 scopy(dp->d_name, enddir); 1224 addfname(expdir); 1225 } else { 1226 char *t; 1227 for (t = enddir, q = dp->d_name; 1228 (*t++ = *q++) != '\0';) 1229 continue; 1230 t[-1] = '/'; 1231 expmeta(t, endname); 1232 } 1233 } 1234 } 1235 closedir(dirp); 1236 if (! atend) 1237 endname[-1] = '/'; 1238 } 1239 1240 1241 /* 1242 * Add a file name to the list. 1243 */ 1244 1245 STATIC void 1246 addfname(char *name) 1247 { 1248 char *p; 1249 struct strlist *sp; 1250 1251 p = stalloc(strlen(name) + 1); 1252 scopy(name, p); 1253 sp = (struct strlist *)stalloc(sizeof *sp); 1254 sp->text = p; 1255 *exparg.lastp = sp; 1256 exparg.lastp = &sp->next; 1257 } 1258 1259 1260 /* 1261 * Sort the results of file name expansion. It calculates the number of 1262 * strings to sort and then calls msort (short for merge sort) to do the 1263 * work. 1264 */ 1265 1266 STATIC struct strlist * 1267 expsort(struct strlist *str) 1268 { 1269 int len; 1270 struct strlist *sp; 1271 1272 len = 0; 1273 for (sp = str ; sp ; sp = sp->next) 1274 len++; 1275 return msort(str, len); 1276 } 1277 1278 1279 STATIC struct strlist * 1280 msort(struct strlist *list, int len) 1281 { 1282 struct strlist *p, *q = NULL; 1283 struct strlist **lpp; 1284 int half; 1285 int n; 1286 1287 if (len <= 1) 1288 return list; 1289 half = len >> 1; 1290 p = list; 1291 for (n = half ; --n >= 0 ; ) { 1292 q = p; 1293 p = p->next; 1294 } 1295 q->next = NULL; /* terminate first half of list */ 1296 q = msort(list, half); /* sort first half of list */ 1297 p = msort(p, len - half); /* sort second half */ 1298 lpp = &list; 1299 for (;;) { 1300 if (strcmp(p->text, q->text) < 0) { 1301 *lpp = p; 1302 lpp = &p->next; 1303 if ((p = *lpp) == NULL) { 1304 *lpp = q; 1305 break; 1306 } 1307 } else { 1308 *lpp = q; 1309 lpp = &q->next; 1310 if ((q = *lpp) == NULL) { 1311 *lpp = p; 1312 break; 1313 } 1314 } 1315 } 1316 return list; 1317 } 1318 1319 1320 1321 /* 1322 * Returns true if the pattern matches the string. 1323 */ 1324 1325 int 1326 patmatch(char *pattern, char *string, int squoted) 1327 { 1328 #ifdef notdef 1329 if (pattern[0] == '!' && pattern[1] == '!') 1330 return 1 - pmatch(pattern + 2, string); 1331 else 1332 #endif 1333 return pmatch(pattern, string, squoted); 1334 } 1335 1336 1337 STATIC int 1338 pmatch(char *pattern, char *string, int squoted) 1339 { 1340 char *p, *q; 1341 char c; 1342 1343 p = pattern; 1344 q = string; 1345 for (;;) { 1346 switch (c = *p++) { 1347 case '\0': 1348 goto breakloop; 1349 case CTLESC: 1350 if (squoted && *q == CTLESC) 1351 q++; 1352 if (*q++ != *p++) 1353 return 0; 1354 break; 1355 case CTLQUOTEMARK: 1356 continue; 1357 case '?': 1358 if (squoted && *q == CTLESC) 1359 q++; 1360 if (*q++ == '\0') 1361 return 0; 1362 break; 1363 case '*': 1364 c = *p; 1365 while (c == CTLQUOTEMARK || c == '*') 1366 c = *++p; 1367 if (c != CTLESC && c != CTLQUOTEMARK && 1368 c != '?' && c != '*' && c != '[') { 1369 while (*q != c) { 1370 if (squoted && *q == CTLESC && 1371 q[1] == c) 1372 break; 1373 if (*q == '\0') 1374 return 0; 1375 if (squoted && *q == CTLESC) 1376 q++; 1377 q++; 1378 } 1379 } 1380 do { 1381 if (pmatch(p, q, squoted)) 1382 return 1; 1383 if (squoted && *q == CTLESC) 1384 q++; 1385 } while (*q++ != '\0'); 1386 return 0; 1387 case '[': { 1388 char *endp; 1389 int invert, found; 1390 char chr; 1391 1392 endp = p; 1393 if (*endp == '!' || *endp == '^') 1394 endp++; 1395 for (;;) { 1396 while (*endp == CTLQUOTEMARK) 1397 endp++; 1398 if (*endp == '\0') 1399 goto dft; /* no matching ] */ 1400 if (*endp == CTLESC) 1401 endp++; 1402 if (*++endp == ']') 1403 break; 1404 } 1405 invert = 0; 1406 if (*p == '!' || *p == '^') { 1407 invert++; 1408 p++; 1409 } 1410 found = 0; 1411 chr = *q++; 1412 if (squoted && chr == CTLESC) 1413 chr = *q++; 1414 if (chr == '\0') 1415 return 0; 1416 c = *p++; 1417 do { 1418 if (c == CTLQUOTEMARK) 1419 continue; 1420 if (c == CTLESC) 1421 c = *p++; 1422 if (*p == '-' && p[1] != ']') { 1423 p++; 1424 while (*p == CTLQUOTEMARK) 1425 p++; 1426 if (*p == CTLESC) 1427 p++; 1428 if ( collate_range_cmp(chr, c) >= 0 1429 && collate_range_cmp(chr, *p) <= 0 1430 ) 1431 found = 1; 1432 p++; 1433 } else { 1434 if (chr == c) 1435 found = 1; 1436 } 1437 } while ((c = *p++) != ']'); 1438 if (found == invert) 1439 return 0; 1440 break; 1441 } 1442 dft: default: 1443 if (squoted && *q == CTLESC) 1444 q++; 1445 if (*q++ != c) 1446 return 0; 1447 break; 1448 } 1449 } 1450 breakloop: 1451 if (*q != '\0') 1452 return 0; 1453 return 1; 1454 } 1455 1456 1457 1458 /* 1459 * Remove any CTLESC characters from a string. 1460 */ 1461 1462 void 1463 rmescapes(char *str) 1464 { 1465 char *p, *q; 1466 1467 p = str; 1468 while (*p != CTLESC && *p != CTLQUOTEMARK) { 1469 if (*p++ == '\0') 1470 return; 1471 } 1472 q = p; 1473 while (*p) { 1474 if (*p == CTLQUOTEMARK) { 1475 p++; 1476 continue; 1477 } 1478 if (*p == CTLESC) 1479 p++; 1480 *q++ = *p++; 1481 } 1482 *q = '\0'; 1483 } 1484 1485 1486 1487 /* 1488 * See if a pattern matches in a case statement. 1489 */ 1490 1491 int 1492 casematch(union node *pattern, char *val) 1493 { 1494 struct stackmark smark; 1495 int result; 1496 char *p; 1497 1498 setstackmark(&smark); 1499 argbackq = pattern->narg.backquote; 1500 STARTSTACKSTR(expdest); 1501 ifslastp = NULL; 1502 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); 1503 STPUTC('\0', expdest); 1504 p = grabstackstr(expdest); 1505 result = patmatch(p, val, 0); 1506 popstackmark(&smark); 1507 return result; 1508 } 1509 1510 /* 1511 * Our own itoa(). 1512 */ 1513 1514 STATIC char * 1515 cvtnum(int num, char *buf) 1516 { 1517 char temp[32]; 1518 int neg = num < 0; 1519 char *p = temp + 31; 1520 1521 temp[31] = '\0'; 1522 1523 do { 1524 *--p = num % 10 + '0'; 1525 } while ((num /= 10) != 0); 1526 1527 if (neg) 1528 *--p = '-'; 1529 1530 while (*p) 1531 STPUTC(*p++, buf); 1532 return buf; 1533 } 1534 1535 /* 1536 * Do most of the work for wordexp(3). 1537 */ 1538 1539 int 1540 wordexpcmd(int argc, char **argv) 1541 { 1542 size_t len; 1543 int i; 1544 1545 out1fmt("%08x", argc - 1); 1546 for (i = 1, len = 0; i < argc; i++) 1547 len += strlen(argv[i]); 1548 out1fmt("%08x", (int)len); 1549 for (i = 1; i < argc; i++) { 1550 out1str(argv[i]); 1551 out1c('\0'); 1552 } 1553 return (0); 1554 } 1555