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 CTLENDVAR: 277 case CTLBACKQ: 278 case CTLBACKQ | CTLQUOTE: 279 case CTLARI: 280 case CTLENDARI: 281 case CTLQUOTEMARK: 282 return (startp); 283 case ':': 284 if (flag & EXP_VARTILDE) 285 goto done; 286 break; 287 case '/': 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, 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(out2, "%s\n", startp); 530 error((char *)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 && *var != '@' && *var != '*') { 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 inquotes) 944 { 945 struct ifsregion *ifsp; 946 947 if (ifslastp == NULL) { 948 ifsp = &ifsfirst; 949 } else { 950 if (ifslastp->endoff == start 951 && ifslastp->inquotes == inquotes) { 952 /* extend previous area */ 953 ifslastp->endoff = end; 954 return; 955 } 956 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 957 ifslastp->next = ifsp; 958 } 959 ifslastp = ifsp; 960 ifslastp->next = NULL; 961 ifslastp->begoff = start; 962 ifslastp->endoff = end; 963 ifslastp->inquotes = inquotes; 964 } 965 966 967 968 /* 969 * Break the argument string into pieces based upon IFS and add the 970 * strings to the argument list. The regions of the string to be 971 * searched for IFS characters have been stored by recordregion. 972 */ 973 STATIC void 974 ifsbreakup(char *string, struct arglist *arglist) 975 { 976 struct ifsregion *ifsp; 977 struct strlist *sp; 978 char *start; 979 char *p; 980 char *q; 981 const char *ifs; 982 const char *ifsspc; 983 int had_param_ch = 0; 984 985 start = string; 986 987 if (ifslastp == NULL) { 988 /* Return entire argument, IFS doesn't apply to any of it */ 989 sp = (struct strlist *)stalloc(sizeof *sp); 990 sp->text = start; 991 *arglist->lastp = sp; 992 arglist->lastp = &sp->next; 993 return; 994 } 995 996 ifs = ifsset() ? ifsval() : " \t\n"; 997 998 for (ifsp = &ifsfirst; ifsp != NULL; ifsp = ifsp->next) { 999 p = string + ifsp->begoff; 1000 while (p < string + ifsp->endoff) { 1001 q = p; 1002 if (*p == CTLESC) 1003 p++; 1004 if (ifsp->inquotes) { 1005 /* Only NULs (should be from "$@") end args */ 1006 had_param_ch = 1; 1007 if (*p != 0) { 1008 p++; 1009 continue; 1010 } 1011 ifsspc = NULL; 1012 } else { 1013 if (!strchr(ifs, *p)) { 1014 had_param_ch = 1; 1015 p++; 1016 continue; 1017 } 1018 ifsspc = strchr(" \t\n", *p); 1019 1020 /* Ignore IFS whitespace at start */ 1021 if (q == start && ifsspc != NULL) { 1022 p++; 1023 start = p; 1024 continue; 1025 } 1026 had_param_ch = 0; 1027 } 1028 1029 /* Save this argument... */ 1030 *q = '\0'; 1031 sp = (struct strlist *)stalloc(sizeof *sp); 1032 sp->text = start; 1033 *arglist->lastp = sp; 1034 arglist->lastp = &sp->next; 1035 p++; 1036 1037 if (ifsspc != NULL) { 1038 /* Ignore further trailing IFS whitespace */ 1039 for (; p < string + ifsp->endoff; p++) { 1040 q = p; 1041 if (*p == CTLESC) 1042 p++; 1043 if (strchr(ifs, *p) == NULL) { 1044 p = q; 1045 break; 1046 } 1047 if (strchr(" \t\n", *p) == NULL) { 1048 p++; 1049 break; 1050 } 1051 } 1052 } 1053 start = p; 1054 } 1055 } 1056 1057 /* 1058 * Save anything left as an argument. 1059 * Traditionally we have treated 'IFS=':'; set -- x$IFS' as 1060 * generating 2 arguments, the second of which is empty. 1061 * Some recent clarification of the Posix spec say that it 1062 * should only generate one.... 1063 */ 1064 if (had_param_ch || *start != 0) { 1065 sp = (struct strlist *)stalloc(sizeof *sp); 1066 sp->text = start; 1067 *arglist->lastp = sp; 1068 arglist->lastp = &sp->next; 1069 } 1070 } 1071 1072 1073 1074 /* 1075 * Expand shell metacharacters. At this point, the only control characters 1076 * should be escapes. The results are stored in the list exparg. 1077 */ 1078 1079 STATIC char *expdir; 1080 1081 1082 STATIC void 1083 expandmeta(struct strlist *str, int flag __unused) 1084 { 1085 char *p; 1086 struct strlist **savelastp; 1087 struct strlist *sp; 1088 char c; 1089 /* TODO - EXP_REDIR */ 1090 1091 while (str) { 1092 if (fflag) 1093 goto nometa; 1094 p = str->text; 1095 for (;;) { /* fast check for meta chars */ 1096 if ((c = *p++) == '\0') 1097 goto nometa; 1098 if (c == '*' || c == '?' || c == '[' || c == '!') 1099 break; 1100 } 1101 savelastp = exparg.lastp; 1102 INTOFF; 1103 if (expdir == NULL) { 1104 int i = strlen(str->text); 1105 expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */ 1106 } 1107 1108 expmeta(expdir, str->text); 1109 ckfree(expdir); 1110 expdir = NULL; 1111 INTON; 1112 if (exparg.lastp == savelastp) { 1113 /* 1114 * no matches 1115 */ 1116 nometa: 1117 *exparg.lastp = str; 1118 rmescapes(str->text); 1119 exparg.lastp = &str->next; 1120 } else { 1121 *exparg.lastp = NULL; 1122 *savelastp = sp = expsort(*savelastp); 1123 while (sp->next != NULL) 1124 sp = sp->next; 1125 exparg.lastp = &sp->next; 1126 } 1127 str = str->next; 1128 } 1129 } 1130 1131 1132 /* 1133 * Do metacharacter (i.e. *, ?, [...]) expansion. 1134 */ 1135 1136 STATIC void 1137 expmeta(char *enddir, char *name) 1138 { 1139 char *p; 1140 char *q; 1141 char *start; 1142 char *endname; 1143 int metaflag; 1144 struct stat statb; 1145 DIR *dirp; 1146 struct dirent *dp; 1147 int atend; 1148 int matchdot; 1149 1150 metaflag = 0; 1151 start = name; 1152 for (p = name ; ; p++) { 1153 if (*p == '*' || *p == '?') 1154 metaflag = 1; 1155 else if (*p == '[') { 1156 q = p + 1; 1157 if (*q == '!' || *q == '^') 1158 q++; 1159 for (;;) { 1160 while (*q == CTLQUOTEMARK) 1161 q++; 1162 if (*q == CTLESC) 1163 q++; 1164 if (*q == '/' || *q == '\0') 1165 break; 1166 if (*++q == ']') { 1167 metaflag = 1; 1168 break; 1169 } 1170 } 1171 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 1172 metaflag = 1; 1173 } else if (*p == '\0') 1174 break; 1175 else if (*p == CTLQUOTEMARK) 1176 continue; 1177 else if (*p == CTLESC) 1178 p++; 1179 if (*p == '/') { 1180 if (metaflag) 1181 break; 1182 start = p + 1; 1183 } 1184 } 1185 if (metaflag == 0) { /* we've reached the end of the file name */ 1186 if (enddir != expdir) 1187 metaflag++; 1188 for (p = name ; ; p++) { 1189 if (*p == CTLQUOTEMARK) 1190 continue; 1191 if (*p == CTLESC) 1192 p++; 1193 *enddir++ = *p; 1194 if (*p == '\0') 1195 break; 1196 } 1197 if (metaflag == 0 || lstat(expdir, &statb) >= 0) 1198 addfname(expdir); 1199 return; 1200 } 1201 endname = p; 1202 if (start != name) { 1203 p = name; 1204 while (p < start) { 1205 while (*p == CTLQUOTEMARK) 1206 p++; 1207 if (*p == CTLESC) 1208 p++; 1209 *enddir++ = *p++; 1210 } 1211 } 1212 if (enddir == expdir) { 1213 p = "."; 1214 } else if (enddir == expdir + 1 && *expdir == '/') { 1215 p = "/"; 1216 } else { 1217 p = expdir; 1218 enddir[-1] = '\0'; 1219 } 1220 if ((dirp = opendir(p)) == NULL) 1221 return; 1222 if (enddir != expdir) 1223 enddir[-1] = '/'; 1224 if (*endname == 0) { 1225 atend = 1; 1226 } else { 1227 atend = 0; 1228 *endname++ = '\0'; 1229 } 1230 matchdot = 0; 1231 p = start; 1232 while (*p == CTLQUOTEMARK) 1233 p++; 1234 if (*p == CTLESC) 1235 p++; 1236 if (*p == '.') 1237 matchdot++; 1238 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 1239 if (dp->d_name[0] == '.' && ! matchdot) 1240 continue; 1241 if (patmatch(start, dp->d_name, 0)) { 1242 if (atend) { 1243 scopy(dp->d_name, enddir); 1244 addfname(expdir); 1245 } else { 1246 for (p = enddir, q = dp->d_name; 1247 (*p++ = *q++) != '\0';) 1248 continue; 1249 p[-1] = '/'; 1250 expmeta(p, endname); 1251 } 1252 } 1253 } 1254 closedir(dirp); 1255 if (! atend) 1256 endname[-1] = '/'; 1257 } 1258 1259 1260 /* 1261 * Add a file name to the list. 1262 */ 1263 1264 STATIC void 1265 addfname(char *name) 1266 { 1267 char *p; 1268 struct strlist *sp; 1269 1270 p = stalloc(strlen(name) + 1); 1271 scopy(name, p); 1272 sp = (struct strlist *)stalloc(sizeof *sp); 1273 sp->text = p; 1274 *exparg.lastp = sp; 1275 exparg.lastp = &sp->next; 1276 } 1277 1278 1279 /* 1280 * Sort the results of file name expansion. It calculates the number of 1281 * strings to sort and then calls msort (short for merge sort) to do the 1282 * work. 1283 */ 1284 1285 STATIC struct strlist * 1286 expsort(struct strlist *str) 1287 { 1288 int len; 1289 struct strlist *sp; 1290 1291 len = 0; 1292 for (sp = str ; sp ; sp = sp->next) 1293 len++; 1294 return msort(str, len); 1295 } 1296 1297 1298 STATIC struct strlist * 1299 msort(struct strlist *list, int len) 1300 { 1301 struct strlist *p, *q = NULL; 1302 struct strlist **lpp; 1303 int half; 1304 int n; 1305 1306 if (len <= 1) 1307 return list; 1308 half = len >> 1; 1309 p = list; 1310 for (n = half ; --n >= 0 ; ) { 1311 q = p; 1312 p = p->next; 1313 } 1314 q->next = NULL; /* terminate first half of list */ 1315 q = msort(list, half); /* sort first half of list */ 1316 p = msort(p, len - half); /* sort second half */ 1317 lpp = &list; 1318 for (;;) { 1319 if (strcmp(p->text, q->text) < 0) { 1320 *lpp = p; 1321 lpp = &p->next; 1322 if ((p = *lpp) == NULL) { 1323 *lpp = q; 1324 break; 1325 } 1326 } else { 1327 *lpp = q; 1328 lpp = &q->next; 1329 if ((q = *lpp) == NULL) { 1330 *lpp = p; 1331 break; 1332 } 1333 } 1334 } 1335 return list; 1336 } 1337 1338 1339 1340 /* 1341 * Returns true if the pattern matches the string. 1342 */ 1343 1344 int 1345 patmatch(const char *pattern, const char *string, int squoted) 1346 { 1347 #ifdef notdef 1348 if (pattern[0] == '!' && pattern[1] == '!') 1349 return 1 - pmatch(pattern + 2, string); 1350 else 1351 #endif 1352 return pmatch(pattern, string, squoted); 1353 } 1354 1355 1356 STATIC int 1357 pmatch(const char *pattern, const char *string, int squoted) 1358 { 1359 const char *p, *q; 1360 char c; 1361 1362 p = pattern; 1363 q = string; 1364 for (;;) { 1365 switch (c = *p++) { 1366 case '\0': 1367 goto breakloop; 1368 case CTLESC: 1369 if (squoted && *q == CTLESC) 1370 q++; 1371 if (*q++ != *p++) 1372 return 0; 1373 break; 1374 case CTLQUOTEMARK: 1375 continue; 1376 case '?': 1377 if (squoted && *q == CTLESC) 1378 q++; 1379 if (*q++ == '\0') 1380 return 0; 1381 break; 1382 case '*': 1383 c = *p; 1384 while (c == CTLQUOTEMARK || c == '*') 1385 c = *++p; 1386 if (c != CTLESC && c != CTLQUOTEMARK && 1387 c != '?' && c != '*' && c != '[') { 1388 while (*q != c) { 1389 if (squoted && *q == CTLESC && 1390 q[1] == c) 1391 break; 1392 if (*q == '\0') 1393 return 0; 1394 if (squoted && *q == CTLESC) 1395 q++; 1396 q++; 1397 } 1398 } 1399 do { 1400 if (pmatch(p, q, squoted)) 1401 return 1; 1402 if (squoted && *q == CTLESC) 1403 q++; 1404 } while (*q++ != '\0'); 1405 return 0; 1406 case '[': { 1407 const char *endp; 1408 int invert, found; 1409 char chr; 1410 1411 endp = p; 1412 if (*endp == '!' || *endp == '^') 1413 endp++; 1414 for (;;) { 1415 while (*endp == CTLQUOTEMARK) 1416 endp++; 1417 if (*endp == '\0') 1418 goto dft; /* no matching ] */ 1419 if (*endp == CTLESC) 1420 endp++; 1421 if (*++endp == ']') 1422 break; 1423 } 1424 invert = 0; 1425 if (*p == '!' || *p == '^') { 1426 invert++; 1427 p++; 1428 } 1429 found = 0; 1430 chr = *q++; 1431 if (squoted && chr == CTLESC) 1432 chr = *q++; 1433 if (chr == '\0') 1434 return 0; 1435 c = *p++; 1436 do { 1437 if (c == CTLQUOTEMARK) 1438 continue; 1439 if (c == CTLESC) 1440 c = *p++; 1441 if (*p == '-' && p[1] != ']') { 1442 p++; 1443 while (*p == CTLQUOTEMARK) 1444 p++; 1445 if (*p == CTLESC) 1446 p++; 1447 if ( collate_range_cmp(chr, c) >= 0 1448 && collate_range_cmp(chr, *p) <= 0 1449 ) 1450 found = 1; 1451 p++; 1452 } else { 1453 if (chr == c) 1454 found = 1; 1455 } 1456 } while ((c = *p++) != ']'); 1457 if (found == invert) 1458 return 0; 1459 break; 1460 } 1461 dft: default: 1462 if (squoted && *q == CTLESC) 1463 q++; 1464 if (*q++ != c) 1465 return 0; 1466 break; 1467 } 1468 } 1469 breakloop: 1470 if (*q != '\0') 1471 return 0; 1472 return 1; 1473 } 1474 1475 1476 1477 /* 1478 * Remove any CTLESC characters from a string. 1479 */ 1480 1481 void 1482 rmescapes(char *str) 1483 { 1484 char *p, *q; 1485 1486 p = str; 1487 while (*p != CTLESC && *p != CTLQUOTEMARK) { 1488 if (*p++ == '\0') 1489 return; 1490 } 1491 q = p; 1492 while (*p) { 1493 if (*p == CTLQUOTEMARK) { 1494 p++; 1495 continue; 1496 } 1497 if (*p == CTLESC) 1498 p++; 1499 *q++ = *p++; 1500 } 1501 *q = '\0'; 1502 } 1503 1504 1505 1506 /* 1507 * See if a pattern matches in a case statement. 1508 */ 1509 1510 int 1511 casematch(union node *pattern, const char *val) 1512 { 1513 struct stackmark smark; 1514 int result; 1515 char *p; 1516 1517 setstackmark(&smark); 1518 argbackq = pattern->narg.backquote; 1519 STARTSTACKSTR(expdest); 1520 ifslastp = NULL; 1521 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); 1522 STPUTC('\0', expdest); 1523 p = grabstackstr(expdest); 1524 result = patmatch(p, val, 0); 1525 popstackmark(&smark); 1526 return result; 1527 } 1528 1529 /* 1530 * Our own itoa(). 1531 */ 1532 1533 STATIC char * 1534 cvtnum(int num, char *buf) 1535 { 1536 char temp[32]; 1537 int neg = num < 0; 1538 char *p = temp + 31; 1539 1540 temp[31] = '\0'; 1541 1542 do { 1543 *--p = num % 10 + '0'; 1544 } while ((num /= 10) != 0); 1545 1546 if (neg) 1547 *--p = '-'; 1548 1549 while (*p) 1550 STPUTC(*p++, buf); 1551 return buf; 1552 } 1553 1554 /* 1555 * Do most of the work for wordexp(3). 1556 */ 1557 1558 int 1559 wordexpcmd(int argc, char **argv) 1560 { 1561 size_t len; 1562 int i; 1563 1564 out1fmt("%08x", argc - 1); 1565 for (i = 1, len = 0; i < argc; i++) 1566 len += strlen(argv[i]); 1567 out1fmt("%08x", (int)len); 1568 for (i = 1; i < argc; i++) { 1569 out1str(argv[i]); 1570 out1c('\0'); 1571 } 1572 return (0); 1573 } 1574