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 inquotes; /* 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(const char *, const 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: /* This means CTL* are always considered quoted. */ 275 case CTLVAR: 276 case CTLBACKQ: 277 case CTLBACKQ | CTLQUOTE: 278 case CTLARI: 279 case CTLENDARI: 280 case CTLQUOTEMARK: 281 return (startp); 282 case ':': 283 if (flag & EXP_VARTILDE) 284 goto done; 285 break; 286 case '/': 287 case CTLENDVAR: 288 goto done; 289 } 290 p++; 291 } 292 done: 293 *p = '\0'; 294 if (*(startp+1) == '\0') { 295 if ((home = lookupvar("HOME")) == NULL) 296 goto lose; 297 } else { 298 if ((pw = getpwnam(startp+1)) == NULL) 299 goto lose; 300 home = pw->pw_dir; 301 } 302 if (*home == '\0') 303 goto lose; 304 *p = c; 305 while ((c = *home++) != '\0') { 306 if (quotes && SQSYNTAX[(int)c] == CCTL) 307 STPUTC(CTLESC, expdest); 308 STPUTC(c, expdest); 309 } 310 return (p); 311 lose: 312 *p = c; 313 return (startp); 314 } 315 316 317 STATIC void 318 removerecordregions(int endoff) 319 { 320 if (ifslastp == NULL) 321 return; 322 323 if (ifsfirst.endoff > endoff) { 324 while (ifsfirst.next != NULL) { 325 struct ifsregion *ifsp; 326 INTOFF; 327 ifsp = ifsfirst.next->next; 328 ckfree(ifsfirst.next); 329 ifsfirst.next = ifsp; 330 INTON; 331 } 332 if (ifsfirst.begoff > endoff) 333 ifslastp = NULL; 334 else { 335 ifslastp = &ifsfirst; 336 ifsfirst.endoff = endoff; 337 } 338 return; 339 } 340 341 ifslastp = &ifsfirst; 342 while (ifslastp->next && ifslastp->next->begoff < endoff) 343 ifslastp=ifslastp->next; 344 while (ifslastp->next != NULL) { 345 struct ifsregion *ifsp; 346 INTOFF; 347 ifsp = ifslastp->next->next; 348 ckfree(ifslastp->next); 349 ifslastp->next = ifsp; 350 INTON; 351 } 352 if (ifslastp->endoff > endoff) 353 ifslastp->endoff = endoff; 354 } 355 356 /* 357 * Expand arithmetic expression. Backup to start of expression, 358 * evaluate, place result in (backed up) result, adjust string position. 359 */ 360 void 361 expari(int flag) 362 { 363 char *p, *start; 364 arith_t result; 365 int begoff; 366 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 367 int quoted; 368 369 370 /* 371 * This routine is slightly over-complicated for 372 * efficiency. First we make sure there is 373 * enough space for the result, which may be bigger 374 * than the expression if we add exponentiation. Next we 375 * scan backwards looking for the start of arithmetic. If the 376 * next previous character is a CTLESC character, then we 377 * have to rescan starting from the beginning since CTLESC 378 * characters have to be processed left to right. 379 */ 380 CHECKSTRSPACE(DIGITS(result) - 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, DIGITS(result), ARITH_FORMAT_STR, 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, (int *)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, (subtype == VSTRIMLEFT || subtype == VSTRIMLEFTMAX || 510 subtype == VSTRIMRIGHT || subtype == VSTRIMRIGHTMAX ? 511 EXP_CASE : 0) | EXP_TILDE); 512 STACKSTRNUL(expdest); 513 herefd = saveherefd; 514 argbackq = saveargbackq; 515 startp = stackblock() + startloc; 516 if (str == NULL) 517 str = stackblock() + strloc; 518 519 switch (subtype) { 520 case VSASSIGN: 521 setvar(str, startp, 0); 522 amount = startp - expdest; 523 STADJUST(amount, expdest); 524 varflags &= ~VSNUL; 525 if (c != 0) 526 *loc = c; 527 return 1; 528 529 case VSQUESTION: 530 if (*p != CTLENDVAR) { 531 outfmt(out2, "%s\n", startp); 532 error((char *)NULL); 533 } 534 error("%.*s: parameter %snot set", (int)(p - str - 1), 535 str, (varflags & VSNUL) ? "null or " 536 : nullstr); 537 return 0; 538 539 case VSTRIMLEFT: 540 for (loc = startp; loc < str; loc++) { 541 c = *loc; 542 *loc = '\0'; 543 if (patmatch(str, startp, varflags & VSQUOTE)) { 544 *loc = c; 545 goto recordleft; 546 } 547 *loc = c; 548 if ((varflags & VSQUOTE) && *loc == CTLESC) 549 loc++; 550 } 551 return 0; 552 553 case VSTRIMLEFTMAX: 554 for (loc = str - 1; loc >= startp;) { 555 c = *loc; 556 *loc = '\0'; 557 if (patmatch(str, startp, varflags & VSQUOTE)) { 558 *loc = c; 559 goto recordleft; 560 } 561 *loc = c; 562 loc--; 563 if ((varflags & VSQUOTE) && loc > startp && 564 *(loc - 1) == CTLESC) { 565 for (q = startp; q < loc; q++) 566 if (*q == CTLESC) 567 q++; 568 if (q > loc) 569 loc--; 570 } 571 } 572 return 0; 573 574 case VSTRIMRIGHT: 575 for (loc = str - 1; loc >= startp;) { 576 if (patmatch(str, loc, varflags & VSQUOTE)) { 577 amount = loc - expdest; 578 STADJUST(amount, expdest); 579 return 1; 580 } 581 loc--; 582 if ((varflags & VSQUOTE) && loc > startp && 583 *(loc - 1) == CTLESC) { 584 for (q = startp; q < loc; q++) 585 if (*q == CTLESC) 586 q++; 587 if (q > loc) 588 loc--; 589 } 590 } 591 return 0; 592 593 case VSTRIMRIGHTMAX: 594 for (loc = startp; loc < str - 1; loc++) { 595 if (patmatch(str, loc, varflags & VSQUOTE)) { 596 amount = loc - expdest; 597 STADJUST(amount, expdest); 598 return 1; 599 } 600 if ((varflags & VSQUOTE) && *loc == CTLESC) 601 loc++; 602 } 603 return 0; 604 605 606 default: 607 abort(); 608 } 609 610 recordleft: 611 amount = ((str - 1) - (loc - startp)) - expdest; 612 STADJUST(amount, expdest); 613 while (loc != str - 1) 614 *startp++ = *loc++; 615 return 1; 616 } 617 618 619 /* 620 * Expand a variable, and return a pointer to the next character in the 621 * input string. 622 */ 623 624 STATIC char * 625 evalvar(char *p, int flag) 626 { 627 int subtype; 628 int varflags; 629 char *var; 630 char *val; 631 int patloc; 632 int c; 633 int set; 634 int special; 635 int startloc; 636 int varlen; 637 int easy; 638 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 639 640 varflags = (unsigned char)*p++; 641 subtype = varflags & VSTYPE; 642 var = p; 643 special = 0; 644 if (! is_name(*p)) 645 special = 1; 646 p = strchr(p, '=') + 1; 647 again: /* jump here after setting a variable with ${var=text} */ 648 if (varflags & VSLINENO) { 649 set = 1; 650 special = 0; 651 val = var; 652 p[-1] = '\0'; /* temporarily overwrite '=' to have \0 653 terminated string */ 654 } else if (special) { 655 set = varisset(var, varflags & VSNUL); 656 val = NULL; 657 } else { 658 val = bltinlookup(var, 1); 659 if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) { 660 val = NULL; 661 set = 0; 662 } else 663 set = 1; 664 } 665 varlen = 0; 666 startloc = expdest - stackblock(); 667 if (!set && uflag && *var != '@' && *var != '*') { 668 switch (subtype) { 669 case VSNORMAL: 670 case VSTRIMLEFT: 671 case VSTRIMLEFTMAX: 672 case VSTRIMRIGHT: 673 case VSTRIMRIGHTMAX: 674 case VSLENGTH: 675 error("%.*s: parameter not set", (int)(p - var - 1), 676 var); 677 } 678 } 679 if (set && subtype != VSPLUS) { 680 /* insert the value of the variable */ 681 if (special) { 682 varvalue(var, varflags & VSQUOTE, subtype, flag); 683 if (subtype == VSLENGTH) { 684 varlen = expdest - stackblock() - startloc; 685 STADJUST(-varlen, expdest); 686 } 687 } else { 688 char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX 689 : BASESYNTAX; 690 691 if (subtype == VSLENGTH) { 692 for (;*val; val++) 693 varlen++; 694 } 695 else { 696 while (*val) { 697 if (quotes && 698 syntax[(int)*val] == CCTL) 699 STPUTC(CTLESC, expdest); 700 STPUTC(*val++, expdest); 701 } 702 703 } 704 } 705 } 706 707 if (subtype == VSPLUS) 708 set = ! set; 709 710 easy = ((varflags & VSQUOTE) == 0 || 711 (*var == '@' && shellparam.nparam != 1)); 712 713 714 switch (subtype) { 715 case VSLENGTH: 716 expdest = cvtnum(varlen, expdest); 717 goto record; 718 719 case VSNORMAL: 720 if (!easy) 721 break; 722 record: 723 recordregion(startloc, expdest - stackblock(), 724 varflags & VSQUOTE); 725 break; 726 727 case VSPLUS: 728 case VSMINUS: 729 if (!set) { 730 argstr(p, flag); 731 break; 732 } 733 if (easy) 734 goto record; 735 break; 736 737 case VSTRIMLEFT: 738 case VSTRIMLEFTMAX: 739 case VSTRIMRIGHT: 740 case VSTRIMRIGHTMAX: 741 if (!set) 742 break; 743 /* 744 * Terminate the string and start recording the pattern 745 * right after it 746 */ 747 STPUTC('\0', expdest); 748 patloc = expdest - stackblock(); 749 if (subevalvar(p, NULL, patloc, subtype, 750 startloc, varflags) == 0) { 751 int amount = (expdest - stackblock() - patloc) + 1; 752 STADJUST(-amount, expdest); 753 } 754 /* Remove any recorded regions beyond start of variable */ 755 removerecordregions(startloc); 756 goto record; 757 758 case VSASSIGN: 759 case VSQUESTION: 760 if (!set) { 761 if (subevalvar(p, var, 0, subtype, startloc, varflags)) { 762 varflags &= ~VSNUL; 763 /* 764 * Remove any recorded regions beyond 765 * start of variable 766 */ 767 removerecordregions(startloc); 768 goto again; 769 } 770 break; 771 } 772 if (easy) 773 goto record; 774 break; 775 776 case VSERROR: 777 c = p - var - 1; 778 error("${%.*s%s}: Bad substitution", c, var, 779 (c > 0 && *p != CTLENDVAR) ? "..." : ""); 780 781 default: 782 abort(); 783 } 784 p[-1] = '='; /* recover overwritten '=' */ 785 786 if (subtype != VSNORMAL) { /* skip to end of alternative */ 787 int nesting = 1; 788 for (;;) { 789 if ((c = *p++) == CTLESC) 790 p++; 791 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { 792 if (set) 793 argbackq = argbackq->next; 794 } else if (c == CTLVAR) { 795 if ((*p++ & VSTYPE) != VSNORMAL) 796 nesting++; 797 } else if (c == CTLENDVAR) { 798 if (--nesting == 0) 799 break; 800 } 801 } 802 } 803 return p; 804 } 805 806 807 808 /* 809 * Test whether a specialized variable is set. 810 */ 811 812 STATIC int 813 varisset(char *name, int nulok) 814 { 815 816 if (*name == '!') 817 return backgndpid != -1; 818 else if (*name == '@' || *name == '*') { 819 if (*shellparam.p == NULL) 820 return 0; 821 822 if (nulok) { 823 char **av; 824 825 for (av = shellparam.p; *av; av++) 826 if (**av != '\0') 827 return 1; 828 return 0; 829 } 830 } else if (is_digit(*name)) { 831 char *ap; 832 int num = atoi(name); 833 834 if (num > shellparam.nparam) 835 return 0; 836 837 if (num == 0) 838 ap = arg0; 839 else 840 ap = shellparam.p[num - 1]; 841 842 if (nulok && (ap == NULL || *ap == '\0')) 843 return 0; 844 } 845 return 1; 846 } 847 848 849 850 /* 851 * Add the value of a specialized variable to the stack string. 852 */ 853 854 STATIC void 855 varvalue(char *name, int quoted, int subtype, int flag) 856 { 857 int num; 858 char *p; 859 int i; 860 char sep; 861 char **ap; 862 char const *syntax; 863 864 #define STRTODEST(p) \ 865 do {\ 866 if (flag & (EXP_FULL | EXP_CASE) && subtype != VSLENGTH) { \ 867 syntax = quoted? DQSYNTAX : BASESYNTAX; \ 868 while (*p) { \ 869 if (syntax[(int)*p] == CCTL) \ 870 STPUTC(CTLESC, expdest); \ 871 STPUTC(*p++, expdest); \ 872 } \ 873 } else \ 874 while (*p) \ 875 STPUTC(*p++, expdest); \ 876 } while (0) 877 878 879 switch (*name) { 880 case '$': 881 num = rootpid; 882 goto numvar; 883 case '?': 884 num = oexitstatus; 885 goto numvar; 886 case '#': 887 num = shellparam.nparam; 888 goto numvar; 889 case '!': 890 num = backgndpid; 891 numvar: 892 expdest = cvtnum(num, expdest); 893 break; 894 case '-': 895 for (i = 0 ; i < NOPTS ; i++) { 896 if (optlist[i].val) 897 STPUTC(optlist[i].letter, expdest); 898 } 899 break; 900 case '@': 901 if (flag & EXP_FULL && quoted) { 902 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 903 STRTODEST(p); 904 if (*ap) 905 STPUTC('\0', expdest); 906 } 907 break; 908 } 909 /* FALLTHROUGH */ 910 case '*': 911 if (ifsset()) 912 sep = ifsval()[0]; 913 else 914 sep = ' '; 915 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 916 STRTODEST(p); 917 if (*ap && sep) 918 STPUTC(sep, expdest); 919 } 920 break; 921 case '0': 922 p = arg0; 923 STRTODEST(p); 924 break; 925 default: 926 if (is_digit(*name)) { 927 num = atoi(name); 928 if (num > 0 && num <= shellparam.nparam) { 929 p = shellparam.p[num - 1]; 930 STRTODEST(p); 931 } 932 } 933 break; 934 } 935 } 936 937 938 939 /* 940 * Record the the fact that we have to scan this region of the 941 * string for IFS characters. 942 */ 943 944 STATIC void 945 recordregion(int start, int end, int inquotes) 946 { 947 struct ifsregion *ifsp; 948 949 if (ifslastp == NULL) { 950 ifsp = &ifsfirst; 951 } else { 952 if (ifslastp->endoff == start 953 && ifslastp->inquotes == inquotes) { 954 /* extend previous area */ 955 ifslastp->endoff = end; 956 return; 957 } 958 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 959 ifslastp->next = ifsp; 960 } 961 ifslastp = ifsp; 962 ifslastp->next = NULL; 963 ifslastp->begoff = start; 964 ifslastp->endoff = end; 965 ifslastp->inquotes = inquotes; 966 } 967 968 969 970 /* 971 * Break the argument string into pieces based upon IFS and add the 972 * strings to the argument list. The regions of the string to be 973 * searched for IFS characters have been stored by recordregion. 974 */ 975 STATIC void 976 ifsbreakup(char *string, struct arglist *arglist) 977 { 978 struct ifsregion *ifsp; 979 struct strlist *sp; 980 char *start; 981 char *p; 982 char *q; 983 const char *ifs; 984 const char *ifsspc; 985 int had_param_ch = 0; 986 987 start = string; 988 989 if (ifslastp == NULL) { 990 /* Return entire argument, IFS doesn't apply to any of it */ 991 sp = (struct strlist *)stalloc(sizeof *sp); 992 sp->text = start; 993 *arglist->lastp = sp; 994 arglist->lastp = &sp->next; 995 return; 996 } 997 998 ifs = ifsset() ? ifsval() : " \t\n"; 999 1000 for (ifsp = &ifsfirst; ifsp != NULL; ifsp = ifsp->next) { 1001 p = string + ifsp->begoff; 1002 while (p < string + ifsp->endoff) { 1003 q = p; 1004 if (*p == CTLESC) 1005 p++; 1006 if (ifsp->inquotes) { 1007 /* Only NULs (should be from "$@") end args */ 1008 had_param_ch = 1; 1009 if (*p != 0) { 1010 p++; 1011 continue; 1012 } 1013 ifsspc = NULL; 1014 } else { 1015 if (!strchr(ifs, *p)) { 1016 had_param_ch = 1; 1017 p++; 1018 continue; 1019 } 1020 ifsspc = strchr(" \t\n", *p); 1021 1022 /* Ignore IFS whitespace at start */ 1023 if (q == start && ifsspc != NULL) { 1024 p++; 1025 start = p; 1026 continue; 1027 } 1028 had_param_ch = 0; 1029 } 1030 1031 /* Save this argument... */ 1032 *q = '\0'; 1033 sp = (struct strlist *)stalloc(sizeof *sp); 1034 sp->text = start; 1035 *arglist->lastp = sp; 1036 arglist->lastp = &sp->next; 1037 p++; 1038 1039 if (ifsspc != NULL) { 1040 /* Ignore further trailing IFS whitespace */ 1041 for (; p < string + ifsp->endoff; p++) { 1042 q = p; 1043 if (*p == CTLESC) 1044 p++; 1045 if (strchr(ifs, *p) == NULL) { 1046 p = q; 1047 break; 1048 } 1049 if (strchr(" \t\n", *p) == NULL) { 1050 p++; 1051 break; 1052 } 1053 } 1054 } 1055 start = p; 1056 } 1057 } 1058 1059 /* 1060 * Save anything left as an argument. 1061 * Traditionally we have treated 'IFS=':'; set -- x$IFS' as 1062 * generating 2 arguments, the second of which is empty. 1063 * Some recent clarification of the Posix spec say that it 1064 * should only generate one.... 1065 */ 1066 if (had_param_ch || *start != 0) { 1067 sp = (struct strlist *)stalloc(sizeof *sp); 1068 sp->text = start; 1069 *arglist->lastp = sp; 1070 arglist->lastp = &sp->next; 1071 } 1072 } 1073 1074 1075 1076 /* 1077 * Expand shell metacharacters. At this point, the only control characters 1078 * should be escapes. The results are stored in the list exparg. 1079 */ 1080 1081 STATIC char *expdir; 1082 1083 1084 STATIC void 1085 expandmeta(struct strlist *str, int flag __unused) 1086 { 1087 char *p; 1088 struct strlist **savelastp; 1089 struct strlist *sp; 1090 char c; 1091 /* TODO - EXP_REDIR */ 1092 1093 while (str) { 1094 if (fflag) 1095 goto nometa; 1096 p = str->text; 1097 for (;;) { /* fast check for meta chars */ 1098 if ((c = *p++) == '\0') 1099 goto nometa; 1100 if (c == '*' || c == '?' || c == '[' || c == '!') 1101 break; 1102 } 1103 savelastp = exparg.lastp; 1104 INTOFF; 1105 if (expdir == NULL) { 1106 int i = strlen(str->text); 1107 expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */ 1108 } 1109 1110 expmeta(expdir, str->text); 1111 ckfree(expdir); 1112 expdir = NULL; 1113 INTON; 1114 if (exparg.lastp == savelastp) { 1115 /* 1116 * no matches 1117 */ 1118 nometa: 1119 *exparg.lastp = str; 1120 rmescapes(str->text); 1121 exparg.lastp = &str->next; 1122 } else { 1123 *exparg.lastp = NULL; 1124 *savelastp = sp = expsort(*savelastp); 1125 while (sp->next != NULL) 1126 sp = sp->next; 1127 exparg.lastp = &sp->next; 1128 } 1129 str = str->next; 1130 } 1131 } 1132 1133 1134 /* 1135 * Do metacharacter (i.e. *, ?, [...]) expansion. 1136 */ 1137 1138 STATIC void 1139 expmeta(char *enddir, char *name) 1140 { 1141 char *p; 1142 char *q; 1143 char *start; 1144 char *endname; 1145 int metaflag; 1146 struct stat statb; 1147 DIR *dirp; 1148 struct dirent *dp; 1149 int atend; 1150 int matchdot; 1151 1152 metaflag = 0; 1153 start = name; 1154 for (p = name ; ; p++) { 1155 if (*p == '*' || *p == '?') 1156 metaflag = 1; 1157 else if (*p == '[') { 1158 q = p + 1; 1159 if (*q == '!' || *q == '^') 1160 q++; 1161 for (;;) { 1162 while (*q == CTLQUOTEMARK) 1163 q++; 1164 if (*q == CTLESC) 1165 q++; 1166 if (*q == '/' || *q == '\0') 1167 break; 1168 if (*++q == ']') { 1169 metaflag = 1; 1170 break; 1171 } 1172 } 1173 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 1174 metaflag = 1; 1175 } else if (*p == '\0') 1176 break; 1177 else if (*p == CTLQUOTEMARK) 1178 continue; 1179 else if (*p == CTLESC) 1180 p++; 1181 if (*p == '/') { 1182 if (metaflag) 1183 break; 1184 start = p + 1; 1185 } 1186 } 1187 if (metaflag == 0) { /* we've reached the end of the file name */ 1188 if (enddir != expdir) 1189 metaflag++; 1190 for (p = name ; ; p++) { 1191 if (*p == CTLQUOTEMARK) 1192 continue; 1193 if (*p == CTLESC) 1194 p++; 1195 *enddir++ = *p; 1196 if (*p == '\0') 1197 break; 1198 } 1199 if (metaflag == 0 || lstat(expdir, &statb) >= 0) 1200 addfname(expdir); 1201 return; 1202 } 1203 endname = p; 1204 if (start != name) { 1205 p = name; 1206 while (p < start) { 1207 while (*p == CTLQUOTEMARK) 1208 p++; 1209 if (*p == CTLESC) 1210 p++; 1211 *enddir++ = *p++; 1212 } 1213 } 1214 if (enddir == expdir) { 1215 p = "."; 1216 } else if (enddir == expdir + 1 && *expdir == '/') { 1217 p = "/"; 1218 } else { 1219 p = expdir; 1220 enddir[-1] = '\0'; 1221 } 1222 if ((dirp = opendir(p)) == NULL) 1223 return; 1224 if (enddir != expdir) 1225 enddir[-1] = '/'; 1226 if (*endname == 0) { 1227 atend = 1; 1228 } else { 1229 atend = 0; 1230 *endname++ = '\0'; 1231 } 1232 matchdot = 0; 1233 p = start; 1234 while (*p == CTLQUOTEMARK) 1235 p++; 1236 if (*p == CTLESC) 1237 p++; 1238 if (*p == '.') 1239 matchdot++; 1240 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 1241 if (dp->d_name[0] == '.' && ! matchdot) 1242 continue; 1243 if (patmatch(start, dp->d_name, 0)) { 1244 if (atend) { 1245 scopy(dp->d_name, enddir); 1246 addfname(expdir); 1247 } else { 1248 for (p = enddir, q = dp->d_name; 1249 (*p++ = *q++) != '\0';) 1250 continue; 1251 p[-1] = '/'; 1252 expmeta(p, endname); 1253 } 1254 } 1255 } 1256 closedir(dirp); 1257 if (! atend) 1258 endname[-1] = '/'; 1259 } 1260 1261 1262 /* 1263 * Add a file name to the list. 1264 */ 1265 1266 STATIC void 1267 addfname(char *name) 1268 { 1269 char *p; 1270 struct strlist *sp; 1271 1272 p = stalloc(strlen(name) + 1); 1273 scopy(name, p); 1274 sp = (struct strlist *)stalloc(sizeof *sp); 1275 sp->text = p; 1276 *exparg.lastp = sp; 1277 exparg.lastp = &sp->next; 1278 } 1279 1280 1281 /* 1282 * Sort the results of file name expansion. It calculates the number of 1283 * strings to sort and then calls msort (short for merge sort) to do the 1284 * work. 1285 */ 1286 1287 STATIC struct strlist * 1288 expsort(struct strlist *str) 1289 { 1290 int len; 1291 struct strlist *sp; 1292 1293 len = 0; 1294 for (sp = str ; sp ; sp = sp->next) 1295 len++; 1296 return msort(str, len); 1297 } 1298 1299 1300 STATIC struct strlist * 1301 msort(struct strlist *list, int len) 1302 { 1303 struct strlist *p, *q = NULL; 1304 struct strlist **lpp; 1305 int half; 1306 int n; 1307 1308 if (len <= 1) 1309 return list; 1310 half = len >> 1; 1311 p = list; 1312 for (n = half ; --n >= 0 ; ) { 1313 q = p; 1314 p = p->next; 1315 } 1316 q->next = NULL; /* terminate first half of list */ 1317 q = msort(list, half); /* sort first half of list */ 1318 p = msort(p, len - half); /* sort second half */ 1319 lpp = &list; 1320 for (;;) { 1321 if (strcmp(p->text, q->text) < 0) { 1322 *lpp = p; 1323 lpp = &p->next; 1324 if ((p = *lpp) == NULL) { 1325 *lpp = q; 1326 break; 1327 } 1328 } else { 1329 *lpp = q; 1330 lpp = &q->next; 1331 if ((q = *lpp) == NULL) { 1332 *lpp = p; 1333 break; 1334 } 1335 } 1336 } 1337 return list; 1338 } 1339 1340 1341 1342 /* 1343 * Returns true if the pattern matches the string. 1344 */ 1345 1346 int 1347 patmatch(const char *pattern, const char *string, int squoted) 1348 { 1349 #ifdef notdef 1350 if (pattern[0] == '!' && pattern[1] == '!') 1351 return 1 - pmatch(pattern + 2, string); 1352 else 1353 #endif 1354 return pmatch(pattern, string, squoted); 1355 } 1356 1357 1358 STATIC int 1359 pmatch(const char *pattern, const char *string, int squoted) 1360 { 1361 const char *p, *q; 1362 char c; 1363 1364 p = pattern; 1365 q = string; 1366 for (;;) { 1367 switch (c = *p++) { 1368 case '\0': 1369 goto breakloop; 1370 case CTLESC: 1371 if (squoted && *q == CTLESC) 1372 q++; 1373 if (*q++ != *p++) 1374 return 0; 1375 break; 1376 case CTLQUOTEMARK: 1377 continue; 1378 case '?': 1379 if (squoted && *q == CTLESC) 1380 q++; 1381 if (*q++ == '\0') 1382 return 0; 1383 break; 1384 case '*': 1385 c = *p; 1386 while (c == CTLQUOTEMARK || c == '*') 1387 c = *++p; 1388 if (c != CTLESC && c != CTLQUOTEMARK && 1389 c != '?' && c != '*' && c != '[') { 1390 while (*q != c) { 1391 if (squoted && *q == CTLESC && 1392 q[1] == c) 1393 break; 1394 if (*q == '\0') 1395 return 0; 1396 if (squoted && *q == CTLESC) 1397 q++; 1398 q++; 1399 } 1400 } 1401 do { 1402 if (pmatch(p, q, squoted)) 1403 return 1; 1404 if (squoted && *q == CTLESC) 1405 q++; 1406 } while (*q++ != '\0'); 1407 return 0; 1408 case '[': { 1409 const char *endp; 1410 int invert, found; 1411 char chr; 1412 1413 endp = p; 1414 if (*endp == '!' || *endp == '^') 1415 endp++; 1416 for (;;) { 1417 while (*endp == CTLQUOTEMARK) 1418 endp++; 1419 if (*endp == '\0') 1420 goto dft; /* no matching ] */ 1421 if (*endp == CTLESC) 1422 endp++; 1423 if (*++endp == ']') 1424 break; 1425 } 1426 invert = 0; 1427 if (*p == '!' || *p == '^') { 1428 invert++; 1429 p++; 1430 } 1431 found = 0; 1432 chr = *q++; 1433 if (squoted && chr == CTLESC) 1434 chr = *q++; 1435 if (chr == '\0') 1436 return 0; 1437 c = *p++; 1438 do { 1439 if (c == CTLQUOTEMARK) 1440 continue; 1441 if (c == CTLESC) 1442 c = *p++; 1443 if (*p == '-' && p[1] != ']') { 1444 p++; 1445 while (*p == CTLQUOTEMARK) 1446 p++; 1447 if (*p == CTLESC) 1448 p++; 1449 if ( collate_range_cmp(chr, c) >= 0 1450 && collate_range_cmp(chr, *p) <= 0 1451 ) 1452 found = 1; 1453 p++; 1454 } else { 1455 if (chr == c) 1456 found = 1; 1457 } 1458 } while ((c = *p++) != ']'); 1459 if (found == invert) 1460 return 0; 1461 break; 1462 } 1463 dft: default: 1464 if (squoted && *q == CTLESC) 1465 q++; 1466 if (*q++ != c) 1467 return 0; 1468 break; 1469 } 1470 } 1471 breakloop: 1472 if (*q != '\0') 1473 return 0; 1474 return 1; 1475 } 1476 1477 1478 1479 /* 1480 * Remove any CTLESC characters from a string. 1481 */ 1482 1483 void 1484 rmescapes(char *str) 1485 { 1486 char *p, *q; 1487 1488 p = str; 1489 while (*p != CTLESC && *p != CTLQUOTEMARK) { 1490 if (*p++ == '\0') 1491 return; 1492 } 1493 q = p; 1494 while (*p) { 1495 if (*p == CTLQUOTEMARK) { 1496 p++; 1497 continue; 1498 } 1499 if (*p == CTLESC) 1500 p++; 1501 *q++ = *p++; 1502 } 1503 *q = '\0'; 1504 } 1505 1506 1507 1508 /* 1509 * See if a pattern matches in a case statement. 1510 */ 1511 1512 int 1513 casematch(union node *pattern, const char *val) 1514 { 1515 struct stackmark smark; 1516 int result; 1517 char *p; 1518 1519 setstackmark(&smark); 1520 argbackq = pattern->narg.backquote; 1521 STARTSTACKSTR(expdest); 1522 ifslastp = NULL; 1523 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); 1524 STPUTC('\0', expdest); 1525 p = grabstackstr(expdest); 1526 result = patmatch(p, val, 0); 1527 popstackmark(&smark); 1528 return result; 1529 } 1530 1531 /* 1532 * Our own itoa(). 1533 */ 1534 1535 STATIC char * 1536 cvtnum(int num, char *buf) 1537 { 1538 char temp[32]; 1539 int neg = num < 0; 1540 char *p = temp + 31; 1541 1542 temp[31] = '\0'; 1543 1544 do { 1545 *--p = num % 10 + '0'; 1546 } while ((num /= 10) != 0); 1547 1548 if (neg) 1549 *--p = '-'; 1550 1551 while (*p) 1552 STPUTC(*p++, buf); 1553 return buf; 1554 } 1555 1556 /* 1557 * Do most of the work for wordexp(3). 1558 */ 1559 1560 int 1561 wordexpcmd(int argc, char **argv) 1562 { 1563 size_t len; 1564 int i; 1565 1566 out1fmt("%08x", argc - 1); 1567 for (i = 1, len = 0; i < argc; i++) 1568 len += strlen(argv[i]); 1569 out1fmt("%08x", (int)len); 1570 for (i = 1; i < argc; i++) { 1571 out1str(argv[i]); 1572 out1c('\0'); 1573 } 1574 return (0); 1575 } 1576