1 /*- 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Kenneth Almquist. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)expand.c 8.5 (Berkeley) 5/15/95 37 * $FreeBSD: src/bin/sh/expand.c,v 1.51 2006/11/07 22:46:13 stefanf Exp $ 38 * $DragonFly: src/bin/sh/expand.c,v 1.9 2007/01/07 16:58:30 pavalos Exp $ 39 */ 40 41 #include <sys/types.h> 42 #include <sys/time.h> 43 #include <sys/stat.h> 44 #include <errno.h> 45 #include <dirent.h> 46 #include <unistd.h> 47 #include <pwd.h> 48 #include <stdlib.h> 49 #include <limits.h> 50 #include <stdio.h> 51 #include <string.h> 52 53 /* 54 * Routines to expand arguments to commands. We have to deal with 55 * backquotes, shell variables, and file metacharacters. 56 */ 57 58 #include "shell.h" 59 #include "main.h" 60 #include "nodes.h" 61 #include "eval.h" 62 #include "expand.h" 63 #include "syntax.h" 64 #include "parser.h" 65 #include "jobs.h" 66 #include "options.h" 67 #include "var.h" 68 #include "input.h" 69 #include "output.h" 70 #include "memalloc.h" 71 #include "error.h" 72 #include "mystring.h" 73 #include "arith.h" 74 #include "show.h" 75 76 /* 77 * Structure specifying which parts of the string should be searched 78 * for IFS characters. 79 */ 80 81 struct ifsregion { 82 struct ifsregion *next; /* next region in list */ 83 int begoff; /* offset of start of region */ 84 int endoff; /* offset of end of region */ 85 int nulonly; /* search for nul bytes only */ 86 }; 87 88 89 STATIC char *expdest; /* output of current string */ 90 STATIC struct nodelist *argbackq; /* list of back quote expressions */ 91 STATIC struct ifsregion ifsfirst; /* first struct in list of ifs regions */ 92 STATIC struct ifsregion *ifslastp; /* last struct in list */ 93 STATIC struct arglist exparg; /* holds expanded arg list */ 94 95 STATIC void argstr(char *, int); 96 STATIC char *exptilde(char *, int); 97 STATIC void expbackq(union node *, int, int); 98 STATIC int subevalvar(char *, char *, int, int, int, int); 99 STATIC char *evalvar(char *, int); 100 STATIC int varisset(char *, int); 101 STATIC void varvalue(char *, int, int, int); 102 STATIC void recordregion(int, int, int); 103 STATIC void removerecordregions(int); 104 STATIC void ifsbreakup(char *, struct arglist *); 105 STATIC void expandmeta(struct strlist *, int); 106 STATIC void expmeta(char *, char *); 107 STATIC void addfname(char *); 108 STATIC struct strlist *expsort(struct strlist *); 109 STATIC struct strlist *msort(struct strlist *, int); 110 STATIC int pmatch(char *, char *, int); 111 STATIC char *cvtnum(int, char *); 112 STATIC int collate_range_cmp(int, int); 113 114 STATIC int 115 collate_range_cmp(int c1, int c2) 116 { 117 static char s1[2], s2[2]; 118 119 s1[0] = c1; 120 s2[0] = c2; 121 return (strcoll(s1, s2)); 122 } 123 124 extern int oexitstatus; 125 126 /* 127 * Expand shell variables and backquotes inside a here document. 128 * union node *arg the document 129 * int fd; where to write the expanded version 130 */ 131 132 void 133 expandhere(union node *arg, int fd) 134 { 135 herefd = fd; 136 expandarg(arg, NULL, 0); 137 xwrite(fd, stackblock(), expdest - stackblock()); 138 } 139 140 141 /* 142 * Perform variable substitution and command substitution on an argument, 143 * placing the resulting list of arguments in arglist. If EXP_FULL is true, 144 * perform splitting and file name expansion. When arglist is NULL, perform 145 * here document expansion. 146 */ 147 148 void 149 expandarg(union node *arg, struct arglist *arglist, int flag) 150 { 151 struct strlist *sp; 152 char *p; 153 154 argbackq = arg->narg.backquote; 155 STARTSTACKSTR(expdest); 156 ifsfirst.next = NULL; 157 ifslastp = NULL; 158 argstr(arg->narg.text, flag); 159 if (arglist == NULL) { 160 return; /* here document expanded */ 161 } 162 STPUTC('\0', expdest); 163 p = grabstackstr(expdest); 164 exparg.lastp = &exparg.list; 165 /* 166 * TODO - EXP_REDIR 167 */ 168 if (flag & EXP_FULL) { 169 ifsbreakup(p, &exparg); 170 *exparg.lastp = NULL; 171 exparg.lastp = &exparg.list; 172 expandmeta(exparg.list, flag); 173 } else { 174 if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */ 175 rmescapes(p); 176 sp = (struct strlist *)stalloc(sizeof (struct strlist)); 177 sp->text = p; 178 *exparg.lastp = sp; 179 exparg.lastp = &sp->next; 180 } 181 while (ifsfirst.next != NULL) { 182 struct ifsregion *ifsp; 183 INTOFF; 184 ifsp = ifsfirst.next->next; 185 ckfree(ifsfirst.next); 186 ifsfirst.next = ifsp; 187 INTON; 188 } 189 *exparg.lastp = NULL; 190 if (exparg.list) { 191 *arglist->lastp = exparg.list; 192 arglist->lastp = exparg.lastp; 193 } 194 } 195 196 197 198 /* 199 * Perform variable and command substitution. If EXP_FULL is set, output CTLESC 200 * characters to allow for further processing. Otherwise treat 201 * $@ like $* since no splitting will be performed. 202 */ 203 204 STATIC void 205 argstr(char *p, int flag) 206 { 207 char c; 208 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); /* do CTLESC */ 209 int firsteq = 1; 210 211 if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE))) 212 p = exptilde(p, flag); 213 for (;;) { 214 switch (c = *p++) { 215 case '\0': 216 case CTLENDVAR: /* ??? */ 217 goto breakloop; 218 case CTLQUOTEMARK: 219 /* "$@" syntax adherence hack */ 220 if (p[0] == CTLVAR && p[2] == '@' && p[3] == '=') 221 break; 222 if ((flag & EXP_FULL) != 0) 223 STPUTC(c, expdest); 224 break; 225 case CTLESC: 226 if (quotes) 227 STPUTC(c, expdest); 228 c = *p++; 229 STPUTC(c, expdest); 230 break; 231 case CTLVAR: 232 p = evalvar(p, flag); 233 break; 234 case CTLBACKQ: 235 case CTLBACKQ|CTLQUOTE: 236 expbackq(argbackq->n, c & CTLQUOTE, flag); 237 argbackq = argbackq->next; 238 break; 239 case CTLENDARI: 240 expari(flag); 241 break; 242 case ':': 243 case '=': 244 /* 245 * sort of a hack - expand tildes in variable 246 * assignments (after the first '=' and after ':'s). 247 */ 248 STPUTC(c, expdest); 249 if (flag & EXP_VARTILDE && *p == '~') { 250 if (c == '=') { 251 if (firsteq) 252 firsteq = 0; 253 else 254 break; 255 } 256 p = exptilde(p, flag); 257 } 258 break; 259 default: 260 STPUTC(c, expdest); 261 } 262 } 263 breakloop:; 264 } 265 266 STATIC char * 267 exptilde(char *p, int flag) 268 { 269 char c, *startp = p; 270 struct passwd *pw; 271 char *home; 272 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 273 274 while ((c = *p) != '\0') { 275 switch(c) { 276 case CTLESC: 277 return (startp); 278 case CTLQUOTEMARK: 279 return (startp); 280 case ':': 281 if (flag & EXP_VARTILDE) 282 goto done; 283 break; 284 case '/': 285 goto done; 286 } 287 p++; 288 } 289 done: 290 *p = '\0'; 291 if (*(startp+1) == '\0') { 292 if ((home = lookupvar("HOME")) == NULL) 293 goto lose; 294 } else { 295 if ((pw = getpwnam(startp+1)) == NULL) 296 goto lose; 297 home = pw->pw_dir; 298 } 299 if (*home == '\0') 300 goto lose; 301 *p = c; 302 while ((c = *home++) != '\0') { 303 if (quotes && SQSYNTAX[(int)c] == CCTL) 304 STPUTC(CTLESC, expdest); 305 STPUTC(c, expdest); 306 } 307 return (p); 308 lose: 309 *p = c; 310 return (startp); 311 } 312 313 314 STATIC void 315 removerecordregions(int endoff) 316 { 317 if (ifslastp == NULL) 318 return; 319 320 if (ifsfirst.endoff > endoff) { 321 while (ifsfirst.next != NULL) { 322 struct ifsregion *ifsp; 323 INTOFF; 324 ifsp = ifsfirst.next->next; 325 ckfree(ifsfirst.next); 326 ifsfirst.next = ifsp; 327 INTON; 328 } 329 if (ifsfirst.begoff > endoff) 330 ifslastp = NULL; 331 else { 332 ifslastp = &ifsfirst; 333 ifsfirst.endoff = endoff; 334 } 335 return; 336 } 337 338 ifslastp = &ifsfirst; 339 while (ifslastp->next && ifslastp->next->begoff < endoff) 340 ifslastp=ifslastp->next; 341 while (ifslastp->next != NULL) { 342 struct ifsregion *ifsp; 343 INTOFF; 344 ifsp = ifslastp->next->next; 345 ckfree(ifslastp->next); 346 ifslastp->next = ifsp; 347 INTON; 348 } 349 if (ifslastp->endoff > endoff) 350 ifslastp->endoff = endoff; 351 } 352 353 /* 354 * Expand arithmetic expression. Backup to start of expression, 355 * evaluate, place result in (backed up) result, adjust string position. 356 */ 357 void 358 expari(int flag) 359 { 360 char *p, *start; 361 int result; 362 int begoff; 363 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 364 int quoted; 365 366 367 /* 368 * This routine is slightly over-complicated for 369 * efficiency. First we make sure there is 370 * enough space for the result, which may be bigger 371 * than the expression if we add exponentiation. Next we 372 * scan backwards looking for the start of arithmetic. If the 373 * next previous character is a CTLESC character, then we 374 * have to rescan starting from the beginning since CTLESC 375 * characters have to be processed left to right. 376 */ 377 #if INT_MAX / 1000000000 >= 10 || INT_MIN / 1000000000 <= -10 378 #error "integers with more than 10 digits are not supported" 379 #endif 380 CHECKSTRSPACE(12 - 2, expdest); 381 USTPUTC('\0', expdest); 382 start = stackblock(); 383 p = expdest - 2; 384 while (p >= start && *p != CTLARI) 385 --p; 386 if (p < start || *p != CTLARI) 387 error("missing CTLARI (shouldn't happen)"); 388 if (p > start && *(p - 1) == CTLESC) 389 for (p = start; *p != CTLARI; p++) 390 if (*p == CTLESC) 391 p++; 392 393 if (p[1] == '"') 394 quoted=1; 395 else 396 quoted=0; 397 begoff = p - start; 398 removerecordregions(begoff); 399 if (quotes) 400 rmescapes(p+2); 401 result = arith(p+2); 402 fmtstr(p, 12, "%d", result); 403 while (*p++) 404 ; 405 if (quoted == 0) 406 recordregion(begoff, p - 1 - start, 0); 407 result = expdest - p + 1; 408 STADJUST(-result, expdest); 409 } 410 411 412 /* 413 * Expand stuff in backwards quotes. 414 */ 415 416 STATIC void 417 expbackq(union node *cmd, int quoted, int flag) 418 { 419 struct backcmd in; 420 int i; 421 char buf[128]; 422 char *p; 423 char *dest = expdest; 424 struct ifsregion saveifs, *savelastp; 425 struct nodelist *saveargbackq; 426 char lastc; 427 int startloc = dest - stackblock(); 428 char const *syntax = quoted? DQSYNTAX : BASESYNTAX; 429 int saveherefd; 430 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 431 432 INTOFF; 433 saveifs = ifsfirst; 434 savelastp = ifslastp; 435 saveargbackq = argbackq; 436 saveherefd = herefd; 437 herefd = -1; 438 p = grabstackstr(dest); 439 evalbackcmd(cmd, &in); 440 ungrabstackstr(p, dest); 441 ifsfirst = saveifs; 442 ifslastp = savelastp; 443 argbackq = saveargbackq; 444 herefd = saveherefd; 445 446 p = in.buf; 447 lastc = '\0'; 448 for (;;) { 449 if (--in.nleft < 0) { 450 if (in.fd < 0) 451 break; 452 while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR); 453 TRACE(("expbackq: read returns %d\n", i)); 454 if (i <= 0) 455 break; 456 p = buf; 457 in.nleft = i - 1; 458 } 459 lastc = *p++; 460 if (lastc != '\0') { 461 if (quotes && syntax[(int)lastc] == CCTL) 462 STPUTC(CTLESC, dest); 463 STPUTC(lastc, dest); 464 } 465 } 466 467 /* Eat all trailing newlines */ 468 for ( ; (dest - stackblock()) > startloc && *(dest-1) == '\n'; ) 469 STUNPUTC(dest); 470 471 if (in.fd >= 0) 472 close(in.fd); 473 if (in.buf) 474 ckfree(in.buf); 475 if (in.jp) 476 exitstatus = waitforjob(in.jp, NULL); 477 if (quoted == 0) 478 recordregion(startloc, dest - stackblock(), 0); 479 TRACE(("evalbackq: size=%d: \"%.*s\"\n", 480 (dest - stackblock()) - startloc, 481 (dest - stackblock()) - startloc, 482 stackblock() + startloc)); 483 expdest = dest; 484 INTON; 485 } 486 487 488 489 STATIC int 490 subevalvar(char *p, char *str, int strloc, int subtype, int startloc, 491 int varflags) 492 { 493 char *startp; 494 char *loc = NULL; 495 char *q; 496 int c = 0; 497 int saveherefd = herefd; 498 struct nodelist *saveargbackq = argbackq; 499 int amount; 500 501 herefd = -1; 502 argstr(p, 0); 503 STACKSTRNUL(expdest); 504 herefd = saveherefd; 505 argbackq = saveargbackq; 506 startp = stackblock() + startloc; 507 if (str == NULL) 508 str = stackblock() + strloc; 509 510 switch (subtype) { 511 case VSASSIGN: 512 setvar(str, startp, 0); 513 amount = startp - expdest; 514 STADJUST(amount, expdest); 515 varflags &= ~VSNUL; 516 if (c != 0) 517 *loc = c; 518 return 1; 519 520 case VSQUESTION: 521 if (*p != CTLENDVAR) { 522 outfmt(&errout, "%s\n", startp); 523 error(NULL); 524 } 525 error("%.*s: parameter %snot set", (int)(p - str - 1), 526 str, (varflags & VSNUL) ? "null or " 527 : nullstr); 528 return 0; 529 530 case VSTRIMLEFT: 531 for (loc = startp; loc < str; loc++) { 532 c = *loc; 533 *loc = '\0'; 534 if (patmatch(str, startp, varflags & VSQUOTE)) { 535 *loc = c; 536 goto recordleft; 537 } 538 *loc = c; 539 if ((varflags & VSQUOTE) && *loc == CTLESC) 540 loc++; 541 } 542 return 0; 543 544 case VSTRIMLEFTMAX: 545 for (loc = str - 1; loc >= startp;) { 546 c = *loc; 547 *loc = '\0'; 548 if (patmatch(str, startp, varflags & VSQUOTE)) { 549 *loc = c; 550 goto recordleft; 551 } 552 *loc = c; 553 loc--; 554 if ((varflags & VSQUOTE) && loc > startp && 555 *(loc - 1) == CTLESC) { 556 for (q = startp; q < loc; q++) 557 if (*q == CTLESC) 558 q++; 559 if (q > loc) 560 loc--; 561 } 562 } 563 return 0; 564 565 case VSTRIMRIGHT: 566 for (loc = str - 1; loc >= startp;) { 567 if (patmatch(str, loc, varflags & VSQUOTE)) { 568 amount = loc - expdest; 569 STADJUST(amount, expdest); 570 return 1; 571 } 572 loc--; 573 if ((varflags & VSQUOTE) && loc > startp && 574 *(loc - 1) == CTLESC) { 575 for (q = startp; q < loc; q++) 576 if (*q == CTLESC) 577 q++; 578 if (q > loc) 579 loc--; 580 } 581 } 582 return 0; 583 584 case VSTRIMRIGHTMAX: 585 for (loc = startp; loc < str - 1; loc++) { 586 if (patmatch(str, loc, varflags & VSQUOTE)) { 587 amount = loc - expdest; 588 STADJUST(amount, expdest); 589 return 1; 590 } 591 if ((varflags & VSQUOTE) && *loc == CTLESC) 592 loc++; 593 } 594 return 0; 595 596 597 default: 598 abort(); 599 } 600 601 recordleft: 602 amount = ((str - 1) - (loc - startp)) - expdest; 603 STADJUST(amount, expdest); 604 while (loc != str - 1) 605 *startp++ = *loc++; 606 return 1; 607 } 608 609 610 /* 611 * Expand a variable, and return a pointer to the next character in the 612 * input string. 613 */ 614 615 STATIC char * 616 evalvar(char *p, int flag) 617 { 618 int subtype; 619 int varflags; 620 char *var; 621 char *val; 622 int patloc; 623 int c; 624 int set; 625 int special; 626 int startloc; 627 int varlen; 628 int easy; 629 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 630 631 varflags = (unsigned char)*p++; 632 subtype = varflags & VSTYPE; 633 var = p; 634 special = 0; 635 if (! is_name(*p)) 636 special = 1; 637 p = strchr(p, '=') + 1; 638 again: /* jump here after setting a variable with ${var=text} */ 639 if (varflags & VSLINENO) { 640 set = 1; 641 special = 0; 642 val = var; 643 p[-1] = '\0'; /* temporarily overwrite '=' to have \0 644 terminated string */ 645 } else if (special) { 646 set = varisset(var, varflags & VSNUL); 647 val = NULL; 648 } else { 649 val = bltinlookup(var, 1); 650 if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) { 651 val = NULL; 652 set = 0; 653 } else 654 set = 1; 655 } 656 varlen = 0; 657 startloc = expdest - stackblock(); 658 if (!set && uflag) { 659 switch (subtype) { 660 case VSNORMAL: 661 case VSTRIMLEFT: 662 case VSTRIMLEFTMAX: 663 case VSTRIMRIGHT: 664 case VSTRIMRIGHTMAX: 665 case VSLENGTH: 666 error("%.*s: parameter not set", (int)(p - var - 1), 667 var); 668 } 669 } 670 if (set && subtype != VSPLUS) { 671 /* insert the value of the variable */ 672 if (special) { 673 varvalue(var, varflags & VSQUOTE, subtype, flag); 674 if (subtype == VSLENGTH) { 675 varlen = expdest - stackblock() - startloc; 676 STADJUST(-varlen, expdest); 677 } 678 } else { 679 char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX 680 : BASESYNTAX; 681 682 if (subtype == VSLENGTH) { 683 for (;*val; val++) 684 varlen++; 685 } 686 else { 687 while (*val) { 688 if (quotes && 689 syntax[(int)*val] == CCTL) 690 STPUTC(CTLESC, expdest); 691 STPUTC(*val++, expdest); 692 } 693 694 } 695 } 696 } 697 698 if (subtype == VSPLUS) 699 set = ! set; 700 701 easy = ((varflags & VSQUOTE) == 0 || 702 (*var == '@' && shellparam.nparam != 1)); 703 704 705 switch (subtype) { 706 case VSLENGTH: 707 expdest = cvtnum(varlen, expdest); 708 goto record; 709 710 case VSNORMAL: 711 if (!easy) 712 break; 713 record: 714 recordregion(startloc, expdest - stackblock(), 715 varflags & VSQUOTE); 716 break; 717 718 case VSPLUS: 719 case VSMINUS: 720 if (!set) { 721 argstr(p, flag); 722 break; 723 } 724 if (easy) 725 goto record; 726 break; 727 728 case VSTRIMLEFT: 729 case VSTRIMLEFTMAX: 730 case VSTRIMRIGHT: 731 case VSTRIMRIGHTMAX: 732 if (!set) 733 break; 734 /* 735 * Terminate the string and start recording the pattern 736 * right after it 737 */ 738 STPUTC('\0', expdest); 739 patloc = expdest - stackblock(); 740 if (subevalvar(p, NULL, patloc, subtype, 741 startloc, varflags) == 0) { 742 int amount = (expdest - stackblock() - patloc) + 1; 743 STADJUST(-amount, expdest); 744 } 745 /* Remove any recorded regions beyond start of variable */ 746 removerecordregions(startloc); 747 goto record; 748 749 case VSASSIGN: 750 case VSQUESTION: 751 if (!set) { 752 if (subevalvar(p, var, 0, subtype, startloc, varflags)) { 753 varflags &= ~VSNUL; 754 /* 755 * Remove any recorded regions beyond 756 * start of variable 757 */ 758 removerecordregions(startloc); 759 goto again; 760 } 761 break; 762 } 763 if (easy) 764 goto record; 765 break; 766 767 case VSERROR: 768 c = p - var - 1; 769 error("${%.*s%s}: Bad substitution", c, var, 770 (c > 0 && *p != CTLENDVAR) ? "..." : ""); 771 772 default: 773 abort(); 774 } 775 p[-1] = '='; /* recover overwritten '=' */ 776 777 if (subtype != VSNORMAL) { /* skip to end of alternative */ 778 int nesting = 1; 779 for (;;) { 780 if ((c = *p++) == CTLESC) 781 p++; 782 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { 783 if (set) 784 argbackq = argbackq->next; 785 } else if (c == CTLVAR) { 786 if ((*p++ & VSTYPE) != VSNORMAL) 787 nesting++; 788 } else if (c == CTLENDVAR) { 789 if (--nesting == 0) 790 break; 791 } 792 } 793 } 794 return p; 795 } 796 797 798 799 /* 800 * Test whether a specialized variable is set. 801 */ 802 803 STATIC int 804 varisset(char *name, int nulok) 805 { 806 807 if (*name == '!') 808 return backgndpid != -1; 809 else if (*name == '@' || *name == '*') { 810 if (*shellparam.p == NULL) 811 return 0; 812 813 if (nulok) { 814 char **av; 815 816 for (av = shellparam.p; *av; av++) 817 if (**av != '\0') 818 return 1; 819 return 0; 820 } 821 } else if (is_digit(*name)) { 822 char *ap; 823 int num = atoi(name); 824 825 if (num > shellparam.nparam) 826 return 0; 827 828 if (num == 0) 829 ap = arg0; 830 else 831 ap = shellparam.p[num - 1]; 832 833 if (nulok && (ap == NULL || *ap == '\0')) 834 return 0; 835 } 836 return 1; 837 } 838 839 840 841 /* 842 * Add the value of a specialized variable to the stack string. 843 */ 844 845 STATIC void 846 varvalue(char *name, int quoted, int subtype, int flag) 847 { 848 int num; 849 char *p; 850 int i; 851 char sep; 852 char **ap; 853 char const *syntax; 854 855 #define STRTODEST(p) \ 856 do {\ 857 if (flag & (EXP_FULL | EXP_CASE) && subtype != VSLENGTH) { \ 858 syntax = quoted? DQSYNTAX : BASESYNTAX; \ 859 while (*p) { \ 860 if (syntax[(int)*p] == CCTL) \ 861 STPUTC(CTLESC, expdest); \ 862 STPUTC(*p++, expdest); \ 863 } \ 864 } else \ 865 while (*p) \ 866 STPUTC(*p++, expdest); \ 867 } while (0) 868 869 870 switch (*name) { 871 case '$': 872 num = rootpid; 873 goto numvar; 874 case '?': 875 num = oexitstatus; 876 goto numvar; 877 case '#': 878 num = shellparam.nparam; 879 goto numvar; 880 case '!': 881 num = backgndpid; 882 numvar: 883 expdest = cvtnum(num, expdest); 884 break; 885 case '-': 886 for (i = 0 ; i < NOPTS ; i++) { 887 if (optlist[i].val) 888 STPUTC(optlist[i].letter, expdest); 889 } 890 break; 891 case '@': 892 if (flag & EXP_FULL && quoted) { 893 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 894 STRTODEST(p); 895 if (*ap) 896 STPUTC('\0', expdest); 897 } 898 break; 899 } 900 /* FALLTHROUGH */ 901 case '*': 902 if (ifsset()) 903 sep = ifsval()[0]; 904 else 905 sep = ' '; 906 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 907 STRTODEST(p); 908 if (*ap && sep) 909 STPUTC(sep, expdest); 910 } 911 break; 912 case '0': 913 p = arg0; 914 STRTODEST(p); 915 break; 916 default: 917 if (is_digit(*name)) { 918 num = atoi(name); 919 if (num > 0 && num <= shellparam.nparam) { 920 p = shellparam.p[num - 1]; 921 STRTODEST(p); 922 } 923 } 924 break; 925 } 926 } 927 928 929 930 /* 931 * Record the the fact that we have to scan this region of the 932 * string for IFS characters. 933 */ 934 935 STATIC void 936 recordregion(int start, int end, int nulonly) 937 { 938 struct ifsregion *ifsp; 939 940 if (ifslastp == NULL) { 941 ifsp = &ifsfirst; 942 } else { 943 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 944 ifslastp->next = ifsp; 945 } 946 ifslastp = ifsp; 947 ifslastp->next = NULL; 948 ifslastp->begoff = start; 949 ifslastp->endoff = end; 950 ifslastp->nulonly = nulonly; 951 } 952 953 954 955 /* 956 * Break the argument string into pieces based upon IFS and add the 957 * strings to the argument list. The regions of the string to be 958 * searched for IFS characters have been stored by recordregion. 959 */ 960 STATIC void 961 ifsbreakup(char *string, struct arglist *arglist) 962 { 963 struct ifsregion *ifsp; 964 struct strlist *sp; 965 char *start; 966 char *p; 967 char *q; 968 const char *ifs; 969 int ifsspc; 970 int nulonly; 971 972 973 start = string; 974 ifsspc = 0; 975 nulonly = 0; 976 if (ifslastp != NULL) { 977 ifsp = &ifsfirst; 978 do { 979 p = string + ifsp->begoff; 980 nulonly = ifsp->nulonly; 981 ifs = nulonly ? nullstr : 982 ( ifsset() ? ifsval() : " \t\n" ); 983 ifsspc = 0; 984 while (p < string + ifsp->endoff) { 985 q = p; 986 if (*p == CTLESC) 987 p++; 988 if (strchr(ifs, *p)) { 989 if (!nulonly) 990 ifsspc = (strchr(" \t\n", *p) != NULL); 991 /* Ignore IFS whitespace at start */ 992 if (q == start && ifsspc) { 993 p++; 994 start = p; 995 continue; 996 } 997 *q = '\0'; 998 sp = (struct strlist *)stalloc(sizeof *sp); 999 sp->text = start; 1000 *arglist->lastp = sp; 1001 arglist->lastp = &sp->next; 1002 p++; 1003 if (!nulonly) { 1004 for (;;) { 1005 if (p >= string + ifsp->endoff) { 1006 break; 1007 } 1008 q = p; 1009 if (*p == CTLESC) 1010 p++; 1011 if (strchr(ifs, *p) == NULL ) { 1012 p = q; 1013 break; 1014 } else if (strchr(" \t\n",*p) == NULL) { 1015 if (ifsspc) { 1016 p++; 1017 ifsspc = 0; 1018 } else { 1019 p = q; 1020 break; 1021 } 1022 } else 1023 p++; 1024 } 1025 } 1026 start = p; 1027 } else 1028 p++; 1029 } 1030 } while ((ifsp = ifsp->next) != NULL); 1031 if (*start || (!ifsspc && start > string)) { 1032 sp = (struct strlist *)stalloc(sizeof *sp); 1033 sp->text = start; 1034 *arglist->lastp = sp; 1035 arglist->lastp = &sp->next; 1036 } 1037 } else { 1038 sp = (struct strlist *)stalloc(sizeof *sp); 1039 sp->text = start; 1040 *arglist->lastp = sp; 1041 arglist->lastp = &sp->next; 1042 } 1043 } 1044 1045 1046 1047 /* 1048 * Expand shell metacharacters. At this point, the only control characters 1049 * should be escapes. The results are stored in the list exparg. 1050 */ 1051 1052 STATIC char *expdir; 1053 1054 1055 STATIC void 1056 expandmeta(struct strlist *str, int flag __unused) 1057 { 1058 char *p; 1059 struct strlist **savelastp; 1060 struct strlist *sp; 1061 char c; 1062 /* TODO - EXP_REDIR */ 1063 1064 while (str) { 1065 if (fflag) 1066 goto nometa; 1067 p = str->text; 1068 for (;;) { /* fast check for meta chars */ 1069 if ((c = *p++) == '\0') 1070 goto nometa; 1071 if (c == '*' || c == '?' || c == '[' || c == '!') 1072 break; 1073 } 1074 savelastp = exparg.lastp; 1075 INTOFF; 1076 if (expdir == NULL) { 1077 int i = strlen(str->text); 1078 expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */ 1079 } 1080 1081 expmeta(expdir, str->text); 1082 ckfree(expdir); 1083 expdir = NULL; 1084 INTON; 1085 if (exparg.lastp == savelastp) { 1086 /* 1087 * no matches 1088 */ 1089 nometa: 1090 *exparg.lastp = str; 1091 rmescapes(str->text); 1092 exparg.lastp = &str->next; 1093 } else { 1094 *exparg.lastp = NULL; 1095 *savelastp = sp = expsort(*savelastp); 1096 while (sp->next != NULL) 1097 sp = sp->next; 1098 exparg.lastp = &sp->next; 1099 } 1100 str = str->next; 1101 } 1102 } 1103 1104 1105 /* 1106 * Do metacharacter (i.e. *, ?, [...]) expansion. 1107 */ 1108 1109 STATIC void 1110 expmeta(char *enddir, char *name) 1111 { 1112 char *p; 1113 const char *q; 1114 char *start; 1115 char *endname; 1116 int metaflag; 1117 struct stat statb; 1118 DIR *dirp; 1119 struct dirent *dp; 1120 int atend; 1121 int matchdot; 1122 1123 metaflag = 0; 1124 start = name; 1125 for (p = name ; ; p++) { 1126 if (*p == '*' || *p == '?') 1127 metaflag = 1; 1128 else if (*p == '[') { 1129 q = p + 1; 1130 if (*q == '!' || *q == '^') 1131 q++; 1132 for (;;) { 1133 while (*q == CTLQUOTEMARK) 1134 q++; 1135 if (*q == CTLESC) 1136 q++; 1137 if (*q == '/' || *q == '\0') 1138 break; 1139 if (*++q == ']') { 1140 metaflag = 1; 1141 break; 1142 } 1143 } 1144 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 1145 metaflag = 1; 1146 } else if (*p == '\0') 1147 break; 1148 else if (*p == CTLQUOTEMARK) 1149 continue; 1150 else if (*p == CTLESC) 1151 p++; 1152 if (*p == '/') { 1153 if (metaflag) 1154 break; 1155 start = p + 1; 1156 } 1157 } 1158 if (metaflag == 0) { /* we've reached the end of the file name */ 1159 if (enddir != expdir) 1160 metaflag++; 1161 for (p = name ; ; p++) { 1162 if (*p == CTLQUOTEMARK) 1163 continue; 1164 if (*p == CTLESC) 1165 p++; 1166 *enddir++ = *p; 1167 if (*p == '\0') 1168 break; 1169 } 1170 if (metaflag == 0 || lstat(expdir, &statb) >= 0) 1171 addfname(expdir); 1172 return; 1173 } 1174 endname = p; 1175 if (start != name) { 1176 p = name; 1177 while (p < start) { 1178 while (*p == CTLQUOTEMARK) 1179 p++; 1180 if (*p == CTLESC) 1181 p++; 1182 *enddir++ = *p++; 1183 } 1184 } 1185 if (enddir == expdir) { 1186 q = "."; 1187 } else if (enddir == expdir + 1 && *expdir == '/') { 1188 q = "/"; 1189 } else { 1190 q = expdir; 1191 enddir[-1] = '\0'; 1192 } 1193 if ((dirp = opendir(q)) == NULL) 1194 return; 1195 if (enddir != expdir) 1196 enddir[-1] = '/'; 1197 if (*endname == 0) { 1198 atend = 1; 1199 } else { 1200 atend = 0; 1201 *endname++ = '\0'; 1202 } 1203 matchdot = 0; 1204 p = start; 1205 while (*p == CTLQUOTEMARK) 1206 p++; 1207 if (*p == CTLESC) 1208 p++; 1209 if (*p == '.') 1210 matchdot++; 1211 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 1212 if (dp->d_name[0] == '.' && ! matchdot) 1213 continue; 1214 if (patmatch(start, dp->d_name, 0)) { 1215 if (atend) { 1216 scopy(dp->d_name, enddir); 1217 addfname(expdir); 1218 } else { 1219 char *t; 1220 for (t = enddir, q = dp->d_name; 1221 (*t++ = *q++) != '\0';) 1222 continue; 1223 t[-1] = '/'; 1224 expmeta(t, endname); 1225 } 1226 } 1227 } 1228 closedir(dirp); 1229 if (! atend) 1230 endname[-1] = '/'; 1231 } 1232 1233 1234 /* 1235 * Add a file name to the list. 1236 */ 1237 1238 STATIC void 1239 addfname(char *name) 1240 { 1241 char *p; 1242 struct strlist *sp; 1243 1244 p = stalloc(strlen(name) + 1); 1245 scopy(name, p); 1246 sp = (struct strlist *)stalloc(sizeof *sp); 1247 sp->text = p; 1248 *exparg.lastp = sp; 1249 exparg.lastp = &sp->next; 1250 } 1251 1252 1253 /* 1254 * Sort the results of file name expansion. It calculates the number of 1255 * strings to sort and then calls msort (short for merge sort) to do the 1256 * work. 1257 */ 1258 1259 STATIC struct strlist * 1260 expsort(struct strlist *str) 1261 { 1262 int len; 1263 struct strlist *sp; 1264 1265 len = 0; 1266 for (sp = str ; sp ; sp = sp->next) 1267 len++; 1268 return msort(str, len); 1269 } 1270 1271 1272 STATIC struct strlist * 1273 msort(struct strlist *list, int len) 1274 { 1275 struct strlist *p, *q = NULL; 1276 struct strlist **lpp; 1277 int half; 1278 int n; 1279 1280 if (len <= 1) 1281 return list; 1282 half = len >> 1; 1283 p = list; 1284 for (n = half ; --n >= 0 ; ) { 1285 q = p; 1286 p = p->next; 1287 } 1288 q->next = NULL; /* terminate first half of list */ 1289 q = msort(list, half); /* sort first half of list */ 1290 p = msort(p, len - half); /* sort second half */ 1291 lpp = &list; 1292 for (;;) { 1293 if (strcmp(p->text, q->text) < 0) { 1294 *lpp = p; 1295 lpp = &p->next; 1296 if ((p = *lpp) == NULL) { 1297 *lpp = q; 1298 break; 1299 } 1300 } else { 1301 *lpp = q; 1302 lpp = &q->next; 1303 if ((q = *lpp) == NULL) { 1304 *lpp = p; 1305 break; 1306 } 1307 } 1308 } 1309 return list; 1310 } 1311 1312 1313 1314 /* 1315 * Returns true if the pattern matches the string. 1316 */ 1317 1318 int 1319 patmatch(char *pattern, char *string, int squoted) 1320 { 1321 #ifdef notdef 1322 if (pattern[0] == '!' && pattern[1] == '!') 1323 return 1 - pmatch(pattern + 2, string); 1324 else 1325 #endif 1326 return pmatch(pattern, string, squoted); 1327 } 1328 1329 1330 STATIC int 1331 pmatch(char *pattern, char *string, int squoted) 1332 { 1333 char *p, *q; 1334 char c; 1335 1336 p = pattern; 1337 q = string; 1338 for (;;) { 1339 switch (c = *p++) { 1340 case '\0': 1341 goto breakloop; 1342 case CTLESC: 1343 if (squoted && *q == CTLESC) 1344 q++; 1345 if (*q++ != *p++) 1346 return 0; 1347 break; 1348 case CTLQUOTEMARK: 1349 continue; 1350 case '?': 1351 if (squoted && *q == CTLESC) 1352 q++; 1353 if (*q++ == '\0') 1354 return 0; 1355 break; 1356 case '*': 1357 c = *p; 1358 while (c == CTLQUOTEMARK || c == '*') 1359 c = *++p; 1360 if (c != CTLESC && c != CTLQUOTEMARK && 1361 c != '?' && c != '*' && c != '[') { 1362 while (*q != c) { 1363 if (squoted && *q == CTLESC && 1364 q[1] == c) 1365 break; 1366 if (*q == '\0') 1367 return 0; 1368 if (squoted && *q == CTLESC) 1369 q++; 1370 q++; 1371 } 1372 } 1373 do { 1374 if (pmatch(p, q, squoted)) 1375 return 1; 1376 if (squoted && *q == CTLESC) 1377 q++; 1378 } while (*q++ != '\0'); 1379 return 0; 1380 case '[': { 1381 char *endp; 1382 int invert, found; 1383 char chr; 1384 1385 endp = p; 1386 if (*endp == '!' || *endp == '^') 1387 endp++; 1388 for (;;) { 1389 while (*endp == CTLQUOTEMARK) 1390 endp++; 1391 if (*endp == '\0') 1392 goto dft; /* no matching ] */ 1393 if (*endp == CTLESC) 1394 endp++; 1395 if (*++endp == ']') 1396 break; 1397 } 1398 invert = 0; 1399 if (*p == '!' || *p == '^') { 1400 invert++; 1401 p++; 1402 } 1403 found = 0; 1404 chr = *q++; 1405 if (squoted && chr == CTLESC) 1406 chr = *q++; 1407 if (chr == '\0') 1408 return 0; 1409 c = *p++; 1410 do { 1411 if (c == CTLQUOTEMARK) 1412 continue; 1413 if (c == CTLESC) 1414 c = *p++; 1415 if (*p == '-' && p[1] != ']') { 1416 p++; 1417 while (*p == CTLQUOTEMARK) 1418 p++; 1419 if (*p == CTLESC) 1420 p++; 1421 if ( collate_range_cmp(chr, c) >= 0 1422 && collate_range_cmp(chr, *p) <= 0 1423 ) 1424 found = 1; 1425 p++; 1426 } else { 1427 if (chr == c) 1428 found = 1; 1429 } 1430 } while ((c = *p++) != ']'); 1431 if (found == invert) 1432 return 0; 1433 break; 1434 } 1435 dft: default: 1436 if (squoted && *q == CTLESC) 1437 q++; 1438 if (*q++ != c) 1439 return 0; 1440 break; 1441 } 1442 } 1443 breakloop: 1444 if (*q != '\0') 1445 return 0; 1446 return 1; 1447 } 1448 1449 1450 1451 /* 1452 * Remove any CTLESC characters from a string. 1453 */ 1454 1455 void 1456 rmescapes(char *str) 1457 { 1458 char *p, *q; 1459 1460 p = str; 1461 while (*p != CTLESC && *p != CTLQUOTEMARK) { 1462 if (*p++ == '\0') 1463 return; 1464 } 1465 q = p; 1466 while (*p) { 1467 if (*p == CTLQUOTEMARK) { 1468 p++; 1469 continue; 1470 } 1471 if (*p == CTLESC) 1472 p++; 1473 *q++ = *p++; 1474 } 1475 *q = '\0'; 1476 } 1477 1478 1479 1480 /* 1481 * See if a pattern matches in a case statement. 1482 */ 1483 1484 int 1485 casematch(union node *pattern, char *val) 1486 { 1487 struct stackmark smark; 1488 int result; 1489 char *p; 1490 1491 setstackmark(&smark); 1492 argbackq = pattern->narg.backquote; 1493 STARTSTACKSTR(expdest); 1494 ifslastp = NULL; 1495 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); 1496 STPUTC('\0', expdest); 1497 p = grabstackstr(expdest); 1498 result = patmatch(p, val, 0); 1499 popstackmark(&smark); 1500 return result; 1501 } 1502 1503 /* 1504 * Our own itoa(). 1505 */ 1506 1507 STATIC char * 1508 cvtnum(int num, char *buf) 1509 { 1510 char temp[32]; 1511 int neg = num < 0; 1512 char *p = temp + 31; 1513 1514 temp[31] = '\0'; 1515 1516 do { 1517 *--p = num % 10 + '0'; 1518 } while ((num /= 10) != 0); 1519 1520 if (neg) 1521 *--p = '-'; 1522 1523 while (*p) 1524 STPUTC(*p++, buf); 1525 return buf; 1526 } 1527 1528 /* 1529 * Do most of the work for wordexp(3). 1530 */ 1531 1532 int 1533 wordexpcmd(int argc, char **argv) 1534 { 1535 size_t len; 1536 int i; 1537 1538 out1fmt("%08x", argc - 1); 1539 for (i = 1, len = 0; i < argc; i++) 1540 len += strlen(argv[i]); 1541 out1fmt("%08x", (int)len); 1542 for (i = 1; i < argc; i++) { 1543 out1str(argv[i]); 1544 out1c('\0'); 1545 } 1546 return (0); 1547 } 1548