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, *q, *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 q = grabstackstr(expdest); 402 result = arith(p+2); 403 ungrabstackstr(q, expdest); 404 fmtstr(p, DIGITS(result), ARITH_FORMAT_STR, result); 405 while (*p++) 406 ; 407 if (quoted == 0) 408 recordregion(begoff, p - 1 - start, 0); 409 result = expdest - p + 1; 410 STADJUST(-result, expdest); 411 } 412 413 414 /* 415 * Expand stuff in backwards quotes. 416 */ 417 418 STATIC void 419 expbackq(union node *cmd, int quoted, int flag) 420 { 421 struct backcmd in; 422 int i; 423 char buf[128]; 424 char *p; 425 char *dest = expdest; 426 struct ifsregion saveifs, *savelastp; 427 struct nodelist *saveargbackq; 428 char lastc; 429 int startloc = dest - stackblock(); 430 char const *syntax = quoted? DQSYNTAX : BASESYNTAX; 431 int saveherefd; 432 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 433 int nnl; 434 435 INTOFF; 436 saveifs = ifsfirst; 437 savelastp = ifslastp; 438 saveargbackq = argbackq; 439 saveherefd = herefd; 440 herefd = -1; 441 p = grabstackstr(dest); 442 evalbackcmd(cmd, &in); 443 ungrabstackstr(p, dest); 444 ifsfirst = saveifs; 445 ifslastp = savelastp; 446 argbackq = saveargbackq; 447 herefd = saveherefd; 448 449 p = in.buf; 450 lastc = '\0'; 451 nnl = 0; 452 /* Don't copy trailing newlines */ 453 for (;;) { 454 if (--in.nleft < 0) { 455 if (in.fd < 0) 456 break; 457 while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR); 458 TRACE(("expbackq: read returns %d\n", i)); 459 if (i <= 0) 460 break; 461 p = buf; 462 in.nleft = i - 1; 463 } 464 lastc = *p++; 465 if (lastc != '\0') { 466 if (quotes && syntax[(int)lastc] == CCTL) 467 STPUTC(CTLESC, dest); 468 if (lastc == '\n') { 469 nnl++; 470 } else { 471 while (nnl > 0) { 472 nnl--; 473 STPUTC('\n', dest); 474 } 475 STPUTC(lastc, dest); 476 } 477 } 478 } 479 480 if (in.fd >= 0) 481 close(in.fd); 482 if (in.buf) 483 ckfree(in.buf); 484 if (in.jp) 485 exitstatus = waitforjob(in.jp, (int *)NULL); 486 if (quoted == 0) 487 recordregion(startloc, dest - stackblock(), 0); 488 TRACE(("evalbackq: size=%d: \"%.*s\"\n", 489 (dest - stackblock()) - startloc, 490 (dest - stackblock()) - startloc, 491 stackblock() + startloc)); 492 expdest = dest; 493 INTON; 494 } 495 496 497 498 STATIC int 499 subevalvar(char *p, char *str, int strloc, int subtype, int startloc, 500 int varflags) 501 { 502 char *startp; 503 char *loc = NULL; 504 char *q; 505 int c = 0; 506 int saveherefd = herefd; 507 struct nodelist *saveargbackq = argbackq; 508 int amount; 509 510 herefd = -1; 511 argstr(p, (subtype == VSTRIMLEFT || subtype == VSTRIMLEFTMAX || 512 subtype == VSTRIMRIGHT || subtype == VSTRIMRIGHTMAX ? 513 EXP_CASE : 0) | EXP_TILDE); 514 STACKSTRNUL(expdest); 515 herefd = saveherefd; 516 argbackq = saveargbackq; 517 startp = stackblock() + startloc; 518 if (str == NULL) 519 str = stackblock() + strloc; 520 521 switch (subtype) { 522 case VSASSIGN: 523 setvar(str, startp, 0); 524 amount = startp - expdest; 525 STADJUST(amount, expdest); 526 varflags &= ~VSNUL; 527 if (c != 0) 528 *loc = c; 529 return 1; 530 531 case VSQUESTION: 532 if (*p != CTLENDVAR) { 533 outfmt(out2, "%s\n", startp); 534 error((char *)NULL); 535 } 536 error("%.*s: parameter %snot set", (int)(p - str - 1), 537 str, (varflags & VSNUL) ? "null or " 538 : nullstr); 539 return 0; 540 541 case VSTRIMLEFT: 542 for (loc = startp; loc < str; loc++) { 543 c = *loc; 544 *loc = '\0'; 545 if (patmatch(str, startp, varflags & VSQUOTE)) { 546 *loc = c; 547 goto recordleft; 548 } 549 *loc = c; 550 if ((varflags & VSQUOTE) && *loc == CTLESC) 551 loc++; 552 } 553 return 0; 554 555 case VSTRIMLEFTMAX: 556 for (loc = str - 1; loc >= startp;) { 557 c = *loc; 558 *loc = '\0'; 559 if (patmatch(str, startp, varflags & VSQUOTE)) { 560 *loc = c; 561 goto recordleft; 562 } 563 *loc = c; 564 loc--; 565 if ((varflags & VSQUOTE) && loc > startp && 566 *(loc - 1) == CTLESC) { 567 for (q = startp; q < loc; q++) 568 if (*q == CTLESC) 569 q++; 570 if (q > loc) 571 loc--; 572 } 573 } 574 return 0; 575 576 case VSTRIMRIGHT: 577 for (loc = str - 1; loc >= startp;) { 578 if (patmatch(str, loc, varflags & VSQUOTE)) { 579 amount = loc - expdest; 580 STADJUST(amount, expdest); 581 return 1; 582 } 583 loc--; 584 if ((varflags & VSQUOTE) && loc > startp && 585 *(loc - 1) == CTLESC) { 586 for (q = startp; q < loc; q++) 587 if (*q == CTLESC) 588 q++; 589 if (q > loc) 590 loc--; 591 } 592 } 593 return 0; 594 595 case VSTRIMRIGHTMAX: 596 for (loc = startp; loc < str - 1; loc++) { 597 if (patmatch(str, loc, varflags & VSQUOTE)) { 598 amount = loc - expdest; 599 STADJUST(amount, expdest); 600 return 1; 601 } 602 if ((varflags & VSQUOTE) && *loc == CTLESC) 603 loc++; 604 } 605 return 0; 606 607 608 default: 609 abort(); 610 } 611 612 recordleft: 613 amount = ((str - 1) - (loc - startp)) - expdest; 614 STADJUST(amount, expdest); 615 while (loc != str - 1) 616 *startp++ = *loc++; 617 return 1; 618 } 619 620 621 /* 622 * Expand a variable, and return a pointer to the next character in the 623 * input string. 624 */ 625 626 STATIC char * 627 evalvar(char *p, int flag) 628 { 629 int subtype; 630 int varflags; 631 char *var; 632 char *val; 633 int patloc; 634 int c; 635 int set; 636 int special; 637 int startloc; 638 int varlen; 639 int easy; 640 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 641 642 varflags = (unsigned char)*p++; 643 subtype = varflags & VSTYPE; 644 var = p; 645 special = 0; 646 if (! is_name(*p)) 647 special = 1; 648 p = strchr(p, '=') + 1; 649 again: /* jump here after setting a variable with ${var=text} */ 650 if (varflags & VSLINENO) { 651 set = 1; 652 special = 0; 653 val = var; 654 p[-1] = '\0'; /* temporarily overwrite '=' to have \0 655 terminated string */ 656 } else if (special) { 657 set = varisset(var, varflags & VSNUL); 658 val = NULL; 659 } else { 660 val = bltinlookup(var, 1); 661 if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) { 662 val = NULL; 663 set = 0; 664 } else 665 set = 1; 666 } 667 varlen = 0; 668 startloc = expdest - stackblock(); 669 if (!set && uflag && *var != '@' && *var != '*') { 670 switch (subtype) { 671 case VSNORMAL: 672 case VSTRIMLEFT: 673 case VSTRIMLEFTMAX: 674 case VSTRIMRIGHT: 675 case VSTRIMRIGHTMAX: 676 case VSLENGTH: 677 error("%.*s: parameter not set", (int)(p - var - 1), 678 var); 679 } 680 } 681 if (set && subtype != VSPLUS) { 682 /* insert the value of the variable */ 683 if (special) { 684 varvalue(var, varflags & VSQUOTE, subtype, flag); 685 if (subtype == VSLENGTH) { 686 varlen = expdest - stackblock() - startloc; 687 STADJUST(-varlen, expdest); 688 } 689 } else { 690 char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX 691 : BASESYNTAX; 692 693 if (subtype == VSLENGTH) { 694 for (;*val; val++) 695 varlen++; 696 } 697 else { 698 while (*val) { 699 if (quotes && 700 syntax[(int)*val] == CCTL) 701 STPUTC(CTLESC, expdest); 702 STPUTC(*val++, expdest); 703 } 704 705 } 706 } 707 } 708 709 if (subtype == VSPLUS) 710 set = ! set; 711 712 easy = ((varflags & VSQUOTE) == 0 || 713 (*var == '@' && shellparam.nparam != 1)); 714 715 716 switch (subtype) { 717 case VSLENGTH: 718 expdest = cvtnum(varlen, expdest); 719 goto record; 720 721 case VSNORMAL: 722 if (!easy) 723 break; 724 record: 725 recordregion(startloc, expdest - stackblock(), 726 varflags & VSQUOTE); 727 break; 728 729 case VSPLUS: 730 case VSMINUS: 731 if (!set) { 732 argstr(p, flag); 733 break; 734 } 735 if (easy) 736 goto record; 737 break; 738 739 case VSTRIMLEFT: 740 case VSTRIMLEFTMAX: 741 case VSTRIMRIGHT: 742 case VSTRIMRIGHTMAX: 743 if (!set) 744 break; 745 /* 746 * Terminate the string and start recording the pattern 747 * right after it 748 */ 749 STPUTC('\0', expdest); 750 patloc = expdest - stackblock(); 751 if (subevalvar(p, NULL, patloc, subtype, 752 startloc, varflags) == 0) { 753 int amount = (expdest - stackblock() - patloc) + 1; 754 STADJUST(-amount, expdest); 755 } 756 /* Remove any recorded regions beyond start of variable */ 757 removerecordregions(startloc); 758 goto record; 759 760 case VSASSIGN: 761 case VSQUESTION: 762 if (!set) { 763 if (subevalvar(p, var, 0, subtype, startloc, varflags)) { 764 varflags &= ~VSNUL; 765 /* 766 * Remove any recorded regions beyond 767 * start of variable 768 */ 769 removerecordregions(startloc); 770 goto again; 771 } 772 break; 773 } 774 if (easy) 775 goto record; 776 break; 777 778 case VSERROR: 779 c = p - var - 1; 780 error("${%.*s%s}: Bad substitution", c, var, 781 (c > 0 && *p != CTLENDVAR) ? "..." : ""); 782 783 default: 784 abort(); 785 } 786 p[-1] = '='; /* recover overwritten '=' */ 787 788 if (subtype != VSNORMAL) { /* skip to end of alternative */ 789 int nesting = 1; 790 for (;;) { 791 if ((c = *p++) == CTLESC) 792 p++; 793 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { 794 if (set) 795 argbackq = argbackq->next; 796 } else if (c == CTLVAR) { 797 if ((*p++ & VSTYPE) != VSNORMAL) 798 nesting++; 799 } else if (c == CTLENDVAR) { 800 if (--nesting == 0) 801 break; 802 } 803 } 804 } 805 return p; 806 } 807 808 809 810 /* 811 * Test whether a specialized variable is set. 812 */ 813 814 STATIC int 815 varisset(char *name, int nulok) 816 { 817 818 if (*name == '!') 819 return backgndpid != -1; 820 else if (*name == '@' || *name == '*') { 821 if (*shellparam.p == NULL) 822 return 0; 823 824 if (nulok) { 825 char **av; 826 827 for (av = shellparam.p; *av; av++) 828 if (**av != '\0') 829 return 1; 830 return 0; 831 } 832 } else if (is_digit(*name)) { 833 char *ap; 834 int num = atoi(name); 835 836 if (num > shellparam.nparam) 837 return 0; 838 839 if (num == 0) 840 ap = arg0; 841 else 842 ap = shellparam.p[num - 1]; 843 844 if (nulok && (ap == NULL || *ap == '\0')) 845 return 0; 846 } 847 return 1; 848 } 849 850 851 852 /* 853 * Add the value of a specialized variable to the stack string. 854 */ 855 856 STATIC void 857 varvalue(char *name, int quoted, int subtype, int flag) 858 { 859 int num; 860 char *p; 861 int i; 862 char sep; 863 char **ap; 864 char const *syntax; 865 866 #define STRTODEST(p) \ 867 do {\ 868 if (flag & (EXP_FULL | EXP_CASE) && subtype != VSLENGTH) { \ 869 syntax = quoted? DQSYNTAX : BASESYNTAX; \ 870 while (*p) { \ 871 if (syntax[(int)*p] == CCTL) \ 872 STPUTC(CTLESC, expdest); \ 873 STPUTC(*p++, expdest); \ 874 } \ 875 } else \ 876 while (*p) \ 877 STPUTC(*p++, expdest); \ 878 } while (0) 879 880 881 switch (*name) { 882 case '$': 883 num = rootpid; 884 goto numvar; 885 case '?': 886 num = oexitstatus; 887 goto numvar; 888 case '#': 889 num = shellparam.nparam; 890 goto numvar; 891 case '!': 892 num = backgndpid; 893 numvar: 894 expdest = cvtnum(num, expdest); 895 break; 896 case '-': 897 for (i = 0 ; i < NOPTS ; i++) { 898 if (optlist[i].val) 899 STPUTC(optlist[i].letter, expdest); 900 } 901 break; 902 case '@': 903 if (flag & EXP_FULL && quoted) { 904 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 905 STRTODEST(p); 906 if (*ap) 907 STPUTC('\0', expdest); 908 } 909 break; 910 } 911 /* FALLTHROUGH */ 912 case '*': 913 if (ifsset()) 914 sep = ifsval()[0]; 915 else 916 sep = ' '; 917 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 918 STRTODEST(p); 919 if (*ap && sep) 920 STPUTC(sep, expdest); 921 } 922 break; 923 case '0': 924 p = arg0; 925 STRTODEST(p); 926 break; 927 default: 928 if (is_digit(*name)) { 929 num = atoi(name); 930 if (num > 0 && num <= shellparam.nparam) { 931 p = shellparam.p[num - 1]; 932 STRTODEST(p); 933 } 934 } 935 break; 936 } 937 } 938 939 940 941 /* 942 * Record the the fact that we have to scan this region of the 943 * string for IFS characters. 944 */ 945 946 STATIC void 947 recordregion(int start, int end, int inquotes) 948 { 949 struct ifsregion *ifsp; 950 951 if (ifslastp == NULL) { 952 ifsp = &ifsfirst; 953 } else { 954 if (ifslastp->endoff == start 955 && ifslastp->inquotes == inquotes) { 956 /* extend previous area */ 957 ifslastp->endoff = end; 958 return; 959 } 960 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 961 ifslastp->next = ifsp; 962 } 963 ifslastp = ifsp; 964 ifslastp->next = NULL; 965 ifslastp->begoff = start; 966 ifslastp->endoff = end; 967 ifslastp->inquotes = inquotes; 968 } 969 970 971 972 /* 973 * Break the argument string into pieces based upon IFS and add the 974 * strings to the argument list. The regions of the string to be 975 * searched for IFS characters have been stored by recordregion. 976 */ 977 STATIC void 978 ifsbreakup(char *string, struct arglist *arglist) 979 { 980 struct ifsregion *ifsp; 981 struct strlist *sp; 982 char *start; 983 char *p; 984 char *q; 985 const char *ifs; 986 const char *ifsspc; 987 int had_param_ch = 0; 988 989 start = string; 990 991 if (ifslastp == NULL) { 992 /* Return entire argument, IFS doesn't apply to any of it */ 993 sp = (struct strlist *)stalloc(sizeof *sp); 994 sp->text = start; 995 *arglist->lastp = sp; 996 arglist->lastp = &sp->next; 997 return; 998 } 999 1000 ifs = ifsset() ? ifsval() : " \t\n"; 1001 1002 for (ifsp = &ifsfirst; ifsp != NULL; ifsp = ifsp->next) { 1003 p = string + ifsp->begoff; 1004 while (p < string + ifsp->endoff) { 1005 q = p; 1006 if (*p == CTLESC) 1007 p++; 1008 if (ifsp->inquotes) { 1009 /* Only NULs (should be from "$@") end args */ 1010 had_param_ch = 1; 1011 if (*p != 0) { 1012 p++; 1013 continue; 1014 } 1015 ifsspc = NULL; 1016 } else { 1017 if (!strchr(ifs, *p)) { 1018 had_param_ch = 1; 1019 p++; 1020 continue; 1021 } 1022 ifsspc = strchr(" \t\n", *p); 1023 1024 /* Ignore IFS whitespace at start */ 1025 if (q == start && ifsspc != NULL) { 1026 p++; 1027 start = p; 1028 continue; 1029 } 1030 had_param_ch = 0; 1031 } 1032 1033 /* Save this argument... */ 1034 *q = '\0'; 1035 sp = (struct strlist *)stalloc(sizeof *sp); 1036 sp->text = start; 1037 *arglist->lastp = sp; 1038 arglist->lastp = &sp->next; 1039 p++; 1040 1041 if (ifsspc != NULL) { 1042 /* Ignore further trailing IFS whitespace */ 1043 for (; p < string + ifsp->endoff; p++) { 1044 q = p; 1045 if (*p == CTLESC) 1046 p++; 1047 if (strchr(ifs, *p) == NULL) { 1048 p = q; 1049 break; 1050 } 1051 if (strchr(" \t\n", *p) == NULL) { 1052 p++; 1053 break; 1054 } 1055 } 1056 } 1057 start = p; 1058 } 1059 } 1060 1061 /* 1062 * Save anything left as an argument. 1063 * Traditionally we have treated 'IFS=':'; set -- x$IFS' as 1064 * generating 2 arguments, the second of which is empty. 1065 * Some recent clarification of the Posix spec say that it 1066 * should only generate one.... 1067 */ 1068 if (had_param_ch || *start != 0) { 1069 sp = (struct strlist *)stalloc(sizeof *sp); 1070 sp->text = start; 1071 *arglist->lastp = sp; 1072 arglist->lastp = &sp->next; 1073 } 1074 } 1075 1076 1077 1078 /* 1079 * Expand shell metacharacters. At this point, the only control characters 1080 * should be escapes. The results are stored in the list exparg. 1081 */ 1082 1083 STATIC char *expdir; 1084 1085 1086 STATIC void 1087 expandmeta(struct strlist *str, int flag __unused) 1088 { 1089 char *p; 1090 struct strlist **savelastp; 1091 struct strlist *sp; 1092 char c; 1093 /* TODO - EXP_REDIR */ 1094 1095 while (str) { 1096 if (fflag) 1097 goto nometa; 1098 p = str->text; 1099 for (;;) { /* fast check for meta chars */ 1100 if ((c = *p++) == '\0') 1101 goto nometa; 1102 if (c == '*' || c == '?' || c == '[' || c == '!') 1103 break; 1104 } 1105 savelastp = exparg.lastp; 1106 INTOFF; 1107 if (expdir == NULL) { 1108 int i = strlen(str->text); 1109 expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */ 1110 } 1111 1112 expmeta(expdir, str->text); 1113 ckfree(expdir); 1114 expdir = NULL; 1115 INTON; 1116 if (exparg.lastp == savelastp) { 1117 /* 1118 * no matches 1119 */ 1120 nometa: 1121 *exparg.lastp = str; 1122 rmescapes(str->text); 1123 exparg.lastp = &str->next; 1124 } else { 1125 *exparg.lastp = NULL; 1126 *savelastp = sp = expsort(*savelastp); 1127 while (sp->next != NULL) 1128 sp = sp->next; 1129 exparg.lastp = &sp->next; 1130 } 1131 str = str->next; 1132 } 1133 } 1134 1135 1136 /* 1137 * Do metacharacter (i.e. *, ?, [...]) expansion. 1138 */ 1139 1140 STATIC void 1141 expmeta(char *enddir, char *name) 1142 { 1143 char *p; 1144 char *q; 1145 char *start; 1146 char *endname; 1147 int metaflag; 1148 struct stat statb; 1149 DIR *dirp; 1150 struct dirent *dp; 1151 int atend; 1152 int matchdot; 1153 1154 metaflag = 0; 1155 start = name; 1156 for (p = name ; ; p++) { 1157 if (*p == '*' || *p == '?') 1158 metaflag = 1; 1159 else if (*p == '[') { 1160 q = p + 1; 1161 if (*q == '!' || *q == '^') 1162 q++; 1163 for (;;) { 1164 while (*q == CTLQUOTEMARK) 1165 q++; 1166 if (*q == CTLESC) 1167 q++; 1168 if (*q == '/' || *q == '\0') 1169 break; 1170 if (*++q == ']') { 1171 metaflag = 1; 1172 break; 1173 } 1174 } 1175 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 1176 metaflag = 1; 1177 } else if (*p == '\0') 1178 break; 1179 else if (*p == CTLQUOTEMARK) 1180 continue; 1181 else if (*p == CTLESC) 1182 p++; 1183 if (*p == '/') { 1184 if (metaflag) 1185 break; 1186 start = p + 1; 1187 } 1188 } 1189 if (metaflag == 0) { /* we've reached the end of the file name */ 1190 if (enddir != expdir) 1191 metaflag++; 1192 for (p = name ; ; p++) { 1193 if (*p == CTLQUOTEMARK) 1194 continue; 1195 if (*p == CTLESC) 1196 p++; 1197 *enddir++ = *p; 1198 if (*p == '\0') 1199 break; 1200 } 1201 if (metaflag == 0 || lstat(expdir, &statb) >= 0) 1202 addfname(expdir); 1203 return; 1204 } 1205 endname = p; 1206 if (start != name) { 1207 p = name; 1208 while (p < start) { 1209 while (*p == CTLQUOTEMARK) 1210 p++; 1211 if (*p == CTLESC) 1212 p++; 1213 *enddir++ = *p++; 1214 } 1215 } 1216 if (enddir == expdir) { 1217 p = "."; 1218 } else if (enddir == expdir + 1 && *expdir == '/') { 1219 p = "/"; 1220 } else { 1221 p = expdir; 1222 enddir[-1] = '\0'; 1223 } 1224 if ((dirp = opendir(p)) == NULL) 1225 return; 1226 if (enddir != expdir) 1227 enddir[-1] = '/'; 1228 if (*endname == 0) { 1229 atend = 1; 1230 } else { 1231 atend = 0; 1232 *endname++ = '\0'; 1233 } 1234 matchdot = 0; 1235 p = start; 1236 while (*p == CTLQUOTEMARK) 1237 p++; 1238 if (*p == CTLESC) 1239 p++; 1240 if (*p == '.') 1241 matchdot++; 1242 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 1243 if (dp->d_name[0] == '.' && ! matchdot) 1244 continue; 1245 if (patmatch(start, dp->d_name, 0)) { 1246 if (atend) { 1247 scopy(dp->d_name, enddir); 1248 addfname(expdir); 1249 } else { 1250 for (p = enddir, q = dp->d_name; 1251 (*p++ = *q++) != '\0';) 1252 continue; 1253 p[-1] = '/'; 1254 expmeta(p, endname); 1255 } 1256 } 1257 } 1258 closedir(dirp); 1259 if (! atend) 1260 endname[-1] = '/'; 1261 } 1262 1263 1264 /* 1265 * Add a file name to the list. 1266 */ 1267 1268 STATIC void 1269 addfname(char *name) 1270 { 1271 char *p; 1272 struct strlist *sp; 1273 1274 p = stalloc(strlen(name) + 1); 1275 scopy(name, p); 1276 sp = (struct strlist *)stalloc(sizeof *sp); 1277 sp->text = p; 1278 *exparg.lastp = sp; 1279 exparg.lastp = &sp->next; 1280 } 1281 1282 1283 /* 1284 * Sort the results of file name expansion. It calculates the number of 1285 * strings to sort and then calls msort (short for merge sort) to do the 1286 * work. 1287 */ 1288 1289 STATIC struct strlist * 1290 expsort(struct strlist *str) 1291 { 1292 int len; 1293 struct strlist *sp; 1294 1295 len = 0; 1296 for (sp = str ; sp ; sp = sp->next) 1297 len++; 1298 return msort(str, len); 1299 } 1300 1301 1302 STATIC struct strlist * 1303 msort(struct strlist *list, int len) 1304 { 1305 struct strlist *p, *q = NULL; 1306 struct strlist **lpp; 1307 int half; 1308 int n; 1309 1310 if (len <= 1) 1311 return list; 1312 half = len >> 1; 1313 p = list; 1314 for (n = half ; --n >= 0 ; ) { 1315 q = p; 1316 p = p->next; 1317 } 1318 q->next = NULL; /* terminate first half of list */ 1319 q = msort(list, half); /* sort first half of list */ 1320 p = msort(p, len - half); /* sort second half */ 1321 lpp = &list; 1322 for (;;) { 1323 if (strcmp(p->text, q->text) < 0) { 1324 *lpp = p; 1325 lpp = &p->next; 1326 if ((p = *lpp) == NULL) { 1327 *lpp = q; 1328 break; 1329 } 1330 } else { 1331 *lpp = q; 1332 lpp = &q->next; 1333 if ((q = *lpp) == NULL) { 1334 *lpp = p; 1335 break; 1336 } 1337 } 1338 } 1339 return list; 1340 } 1341 1342 1343 1344 /* 1345 * Returns true if the pattern matches the string. 1346 */ 1347 1348 int 1349 patmatch(const char *pattern, const char *string, int squoted) 1350 { 1351 #ifdef notdef 1352 if (pattern[0] == '!' && pattern[1] == '!') 1353 return 1 - pmatch(pattern + 2, string); 1354 else 1355 #endif 1356 return pmatch(pattern, string, squoted); 1357 } 1358 1359 1360 STATIC int 1361 pmatch(const char *pattern, const char *string, int squoted) 1362 { 1363 const char *p, *q; 1364 char c; 1365 1366 p = pattern; 1367 q = string; 1368 for (;;) { 1369 switch (c = *p++) { 1370 case '\0': 1371 goto breakloop; 1372 case CTLESC: 1373 if (squoted && *q == CTLESC) 1374 q++; 1375 if (*q++ != *p++) 1376 return 0; 1377 break; 1378 case CTLQUOTEMARK: 1379 continue; 1380 case '?': 1381 if (squoted && *q == CTLESC) 1382 q++; 1383 if (*q++ == '\0') 1384 return 0; 1385 break; 1386 case '*': 1387 c = *p; 1388 while (c == CTLQUOTEMARK || c == '*') 1389 c = *++p; 1390 if (c != CTLESC && c != CTLQUOTEMARK && 1391 c != '?' && c != '*' && c != '[') { 1392 while (*q != c) { 1393 if (squoted && *q == CTLESC && 1394 q[1] == c) 1395 break; 1396 if (*q == '\0') 1397 return 0; 1398 if (squoted && *q == CTLESC) 1399 q++; 1400 q++; 1401 } 1402 } 1403 do { 1404 if (pmatch(p, q, squoted)) 1405 return 1; 1406 if (squoted && *q == CTLESC) 1407 q++; 1408 } while (*q++ != '\0'); 1409 return 0; 1410 case '[': { 1411 const char *endp; 1412 int invert, found; 1413 char chr; 1414 1415 endp = p; 1416 if (*endp == '!' || *endp == '^') 1417 endp++; 1418 for (;;) { 1419 while (*endp == CTLQUOTEMARK) 1420 endp++; 1421 if (*endp == '\0') 1422 goto dft; /* no matching ] */ 1423 if (*endp == CTLESC) 1424 endp++; 1425 if (*++endp == ']') 1426 break; 1427 } 1428 invert = 0; 1429 if (*p == '!' || *p == '^') { 1430 invert++; 1431 p++; 1432 } 1433 found = 0; 1434 chr = *q++; 1435 if (squoted && chr == CTLESC) 1436 chr = *q++; 1437 if (chr == '\0') 1438 return 0; 1439 c = *p++; 1440 do { 1441 if (c == CTLQUOTEMARK) 1442 continue; 1443 if (c == CTLESC) 1444 c = *p++; 1445 if (*p == '-' && p[1] != ']') { 1446 p++; 1447 while (*p == CTLQUOTEMARK) 1448 p++; 1449 if (*p == CTLESC) 1450 p++; 1451 if ( collate_range_cmp(chr, c) >= 0 1452 && collate_range_cmp(chr, *p) <= 0 1453 ) 1454 found = 1; 1455 p++; 1456 } else { 1457 if (chr == c) 1458 found = 1; 1459 } 1460 } while ((c = *p++) != ']'); 1461 if (found == invert) 1462 return 0; 1463 break; 1464 } 1465 dft: default: 1466 if (squoted && *q == CTLESC) 1467 q++; 1468 if (*q++ != c) 1469 return 0; 1470 break; 1471 } 1472 } 1473 breakloop: 1474 if (*q != '\0') 1475 return 0; 1476 return 1; 1477 } 1478 1479 1480 1481 /* 1482 * Remove any CTLESC characters from a string. 1483 */ 1484 1485 void 1486 rmescapes(char *str) 1487 { 1488 char *p, *q; 1489 1490 p = str; 1491 while (*p != CTLESC && *p != CTLQUOTEMARK) { 1492 if (*p++ == '\0') 1493 return; 1494 } 1495 q = p; 1496 while (*p) { 1497 if (*p == CTLQUOTEMARK) { 1498 p++; 1499 continue; 1500 } 1501 if (*p == CTLESC) 1502 p++; 1503 *q++ = *p++; 1504 } 1505 *q = '\0'; 1506 } 1507 1508 1509 1510 /* 1511 * See if a pattern matches in a case statement. 1512 */ 1513 1514 int 1515 casematch(union node *pattern, const char *val) 1516 { 1517 struct stackmark smark; 1518 int result; 1519 char *p; 1520 1521 setstackmark(&smark); 1522 argbackq = pattern->narg.backquote; 1523 STARTSTACKSTR(expdest); 1524 ifslastp = NULL; 1525 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); 1526 STPUTC('\0', expdest); 1527 p = grabstackstr(expdest); 1528 result = patmatch(p, val, 0); 1529 popstackmark(&smark); 1530 return result; 1531 } 1532 1533 /* 1534 * Our own itoa(). 1535 */ 1536 1537 STATIC char * 1538 cvtnum(int num, char *buf) 1539 { 1540 char temp[32]; 1541 int neg = num < 0; 1542 char *p = temp + 31; 1543 1544 temp[31] = '\0'; 1545 1546 do { 1547 *--p = num % 10 + '0'; 1548 } while ((num /= 10) != 0); 1549 1550 if (neg) 1551 *--p = '-'; 1552 1553 while (*p) 1554 STPUTC(*p++, buf); 1555 return buf; 1556 } 1557 1558 /* 1559 * Do most of the work for wordexp(3). 1560 */ 1561 1562 int 1563 wordexpcmd(int argc, char **argv) 1564 { 1565 size_t len; 1566 int i; 1567 1568 out1fmt("%08x", argc - 1); 1569 for (i = 1, len = 0; i < argc; i++) 1570 len += strlen(argv[i]); 1571 out1fmt("%08x", (int)len); 1572 for (i = 1; i < argc; i++) { 1573 out1str(argv[i]); 1574 out1c('\0'); 1575 } 1576 return (0); 1577 } 1578