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 1.31.2.5 2003/01/17 07:44:01 tjr Exp $ 38 * $DragonFly: src/bin/sh/expand.c,v 1.7 2006/09/28 22:29:44 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 52 /* 53 * Routines to expand arguments to commands. We have to deal with 54 * backquotes, shell variables, and file metacharacters. 55 */ 56 57 #include "shell.h" 58 #include "main.h" 59 #include "nodes.h" 60 #include "eval.h" 61 #include "expand.h" 62 #include "syntax.h" 63 #include "parser.h" 64 #include "jobs.h" 65 #include "options.h" 66 #include "var.h" 67 #include "input.h" 68 #include "output.h" 69 #include "memalloc.h" 70 #include "error.h" 71 #include "mystring.h" 72 #include "arith.h" 73 #include "show.h" 74 75 /* 76 * Structure specifying which parts of the string should be searched 77 * for IFS characters. 78 */ 79 80 struct ifsregion { 81 struct ifsregion *next; /* next region in list */ 82 int begoff; /* offset of start of region */ 83 int endoff; /* offset of end of region */ 84 int nulonly; /* search for nul bytes only */ 85 }; 86 87 88 STATIC char *expdest; /* output of current string */ 89 STATIC struct nodelist *argbackq; /* list of back quote expressions */ 90 STATIC struct ifsregion ifsfirst; /* first struct in list of ifs regions */ 91 STATIC struct ifsregion *ifslastp; /* last struct in list */ 92 STATIC struct arglist exparg; /* holds expanded arg list */ 93 94 STATIC void argstr(char *, int); 95 STATIC char *exptilde(char *, int); 96 STATIC void expbackq(union node *, int, int); 97 STATIC int subevalvar(char *, char *, int, int, int, int); 98 STATIC char *evalvar(char *, int); 99 STATIC int varisset(char *, int); 100 STATIC void varvalue(char *, int, int); 101 STATIC void recordregion(int, int, int); 102 STATIC void removerecordregions(int); 103 STATIC void ifsbreakup(char *, struct arglist *); 104 STATIC void expandmeta(struct strlist *, int); 105 STATIC void expmeta(char *, char *); 106 STATIC void addfname(char *); 107 STATIC struct strlist *expsort(struct strlist *); 108 STATIC struct strlist *msort(struct strlist *, int); 109 STATIC int pmatch(char *, char *, int); 110 STATIC char *cvtnum(int, char *); 111 STATIC int collate_range_cmp(int, int); 112 113 STATIC int 114 collate_range_cmp (int c1, int c2) 115 { 116 static char s1[2], s2[2]; 117 int ret; 118 119 c1 &= UCHAR_MAX; 120 c2 &= UCHAR_MAX; 121 if (c1 == c2) 122 return (0); 123 s1[0] = c1; 124 s2[0] = c2; 125 if ((ret = strcoll(s1, s2)) != 0) 126 return (ret); 127 return (c1 - c2); 128 } 129 130 extern int oexitstatus; 131 132 /* 133 * Expand shell variables and backquotes inside a here document. 134 * union node *arg the document 135 * int fd; where to write the expanded version 136 */ 137 138 void 139 expandhere(union node *arg, int fd) 140 { 141 herefd = fd; 142 expandarg(arg, (struct arglist *)NULL, 0); 143 xwrite(fd, stackblock(), expdest - stackblock()); 144 } 145 146 147 /* 148 * Perform variable substitution and command substitution on an argument, 149 * placing the resulting list of arguments in arglist. If EXP_FULL is true, 150 * perform splitting and file name expansion. When arglist is NULL, perform 151 * here document expansion. 152 */ 153 154 void 155 expandarg(union node *arg, struct arglist *arglist, int flag) 156 { 157 struct strlist *sp; 158 char *p; 159 160 argbackq = arg->narg.backquote; 161 STARTSTACKSTR(expdest); 162 ifsfirst.next = NULL; 163 ifslastp = NULL; 164 argstr(arg->narg.text, flag); 165 if (arglist == NULL) { 166 return; /* here document expanded */ 167 } 168 STPUTC('\0', expdest); 169 p = grabstackstr(expdest); 170 exparg.lastp = &exparg.list; 171 /* 172 * TODO - EXP_REDIR 173 */ 174 if (flag & EXP_FULL) { 175 ifsbreakup(p, &exparg); 176 *exparg.lastp = NULL; 177 exparg.lastp = &exparg.list; 178 expandmeta(exparg.list, flag); 179 } else { 180 if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */ 181 rmescapes(p); 182 sp = (struct strlist *)stalloc(sizeof (struct strlist)); 183 sp->text = p; 184 *exparg.lastp = sp; 185 exparg.lastp = &sp->next; 186 } 187 while (ifsfirst.next != NULL) { 188 struct ifsregion *ifsp; 189 INTOFF; 190 ifsp = ifsfirst.next->next; 191 ckfree(ifsfirst.next); 192 ifsfirst.next = ifsp; 193 INTON; 194 } 195 *exparg.lastp = NULL; 196 if (exparg.list) { 197 *arglist->lastp = exparg.list; 198 arglist->lastp = exparg.lastp; 199 } 200 } 201 202 203 204 /* 205 * Perform variable and command substitution. If EXP_FULL is set, output CTLESC 206 * characters to allow for further processing. Otherwise treat 207 * $@ like $* since no splitting will be performed. 208 */ 209 210 STATIC void 211 argstr(char *p, int flag) 212 { 213 char c; 214 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); /* do CTLESC */ 215 int firsteq = 1; 216 217 if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE))) 218 p = exptilde(p, flag); 219 for (;;) { 220 switch (c = *p++) { 221 case '\0': 222 case CTLENDVAR: /* ??? */ 223 goto breakloop; 224 case CTLQUOTEMARK: 225 /* "$@" syntax adherence hack */ 226 if (p[0] == CTLVAR && p[2] == '@' && p[3] == '=') 227 break; 228 if ((flag & EXP_FULL) != 0) 229 STPUTC(c, expdest); 230 break; 231 case CTLESC: 232 if (quotes) 233 STPUTC(c, expdest); 234 c = *p++; 235 STPUTC(c, expdest); 236 break; 237 case CTLVAR: 238 p = evalvar(p, flag); 239 break; 240 case CTLBACKQ: 241 case CTLBACKQ|CTLQUOTE: 242 expbackq(argbackq->n, c & CTLQUOTE, flag); 243 argbackq = argbackq->next; 244 break; 245 case CTLENDARI: 246 expari(flag); 247 break; 248 case ':': 249 case '=': 250 /* 251 * sort of a hack - expand tildes in variable 252 * assignments (after the first '=' and after ':'s). 253 */ 254 STPUTC(c, expdest); 255 if (flag & EXP_VARTILDE && *p == '~') { 256 if (c == '=') { 257 if (firsteq) 258 firsteq = 0; 259 else 260 break; 261 } 262 p = exptilde(p, flag); 263 } 264 break; 265 default: 266 STPUTC(c, expdest); 267 } 268 } 269 breakloop:; 270 } 271 272 STATIC char * 273 exptilde(char *p, int flag) 274 { 275 char c, *startp = p; 276 struct passwd *pw; 277 char *home; 278 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 279 280 while ((c = *p) != '\0') { 281 switch(c) { 282 case CTLESC: 283 return (startp); 284 case CTLQUOTEMARK: 285 return (startp); 286 case ':': 287 if (flag & EXP_VARTILDE) 288 goto done; 289 break; 290 case '/': 291 goto done; 292 } 293 p++; 294 } 295 done: 296 *p = '\0'; 297 if (*(startp+1) == '\0') { 298 if ((home = lookupvar("HOME")) == NULL) 299 goto lose; 300 } else { 301 if ((pw = getpwnam(startp+1)) == NULL) 302 goto lose; 303 home = pw->pw_dir; 304 } 305 if (*home == '\0') 306 goto lose; 307 *p = c; 308 while ((c = *home++) != '\0') { 309 if (quotes && SQSYNTAX[(int)c] == CCTL) 310 STPUTC(CTLESC, expdest); 311 STPUTC(c, expdest); 312 } 313 return (p); 314 lose: 315 *p = c; 316 return (startp); 317 } 318 319 320 STATIC void 321 removerecordregions(int endoff) 322 { 323 if (ifslastp == NULL) 324 return; 325 326 if (ifsfirst.endoff > endoff) { 327 while (ifsfirst.next != NULL) { 328 struct ifsregion *ifsp; 329 INTOFF; 330 ifsp = ifsfirst.next->next; 331 ckfree(ifsfirst.next); 332 ifsfirst.next = ifsp; 333 INTON; 334 } 335 if (ifsfirst.begoff > endoff) 336 ifslastp = NULL; 337 else { 338 ifslastp = &ifsfirst; 339 ifsfirst.endoff = endoff; 340 } 341 return; 342 } 343 344 ifslastp = &ifsfirst; 345 while (ifslastp->next && ifslastp->next->begoff < endoff) 346 ifslastp=ifslastp->next; 347 while (ifslastp->next != NULL) { 348 struct ifsregion *ifsp; 349 INTOFF; 350 ifsp = ifslastp->next->next; 351 ckfree(ifslastp->next); 352 ifslastp->next = ifsp; 353 INTON; 354 } 355 if (ifslastp->endoff > endoff) 356 ifslastp->endoff = endoff; 357 } 358 359 /* 360 * Expand arithmetic expression. Backup to start of expression, 361 * evaluate, place result in (backed up) result, adjust string position. 362 */ 363 void 364 expari(int flag) 365 { 366 char *p, *start; 367 int result; 368 int begoff; 369 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 370 int quoted; 371 372 373 /* 374 * This routine is slightly over-complicated for 375 * efficiency. First we make sure there is 376 * enough space for the result, which may be bigger 377 * than the expression if we add exponentiation. Next we 378 * scan backwards looking for the start of arithmetic. If the 379 * next previous character is a CTLESC character, then we 380 * have to rescan starting from the beginning since CTLESC 381 * characters have to be processed left to right. 382 */ 383 #if INT_MAX / 1000000000 >= 10 || INT_MIN / 1000000000 <= -10 384 #error "integers with more than 10 digits are not supported" 385 #endif 386 CHECKSTRSPACE(12 - 2, expdest); 387 USTPUTC('\0', expdest); 388 start = stackblock(); 389 p = expdest - 2; 390 while (p >= start && *p != CTLARI) 391 --p; 392 if (p < start || *p != CTLARI) 393 error("missing CTLARI (shouldn't happen)"); 394 if (p > start && *(p - 1) == CTLESC) 395 for (p = start; *p != CTLARI; p++) 396 if (*p == CTLESC) 397 p++; 398 399 if (p[1] == '"') 400 quoted=1; 401 else 402 quoted=0; 403 begoff = p - start; 404 removerecordregions(begoff); 405 if (quotes) 406 rmescapes(p+2); 407 result = arith(p+2); 408 fmtstr(p, 12, "%d", result); 409 while (*p++) 410 ; 411 if (quoted == 0) 412 recordregion(begoff, p - 1 - start, 0); 413 result = expdest - p + 1; 414 STADJUST(-result, expdest); 415 } 416 417 418 /* 419 * Expand stuff in backwards quotes. 420 */ 421 422 STATIC void 423 expbackq(union node *cmd, int quoted, int flag) 424 { 425 struct backcmd in; 426 int i; 427 char buf[128]; 428 char *p; 429 char *dest = expdest; 430 struct ifsregion saveifs, *savelastp; 431 struct nodelist *saveargbackq; 432 char lastc; 433 int startloc = dest - stackblock(); 434 char const *syntax = quoted? DQSYNTAX : BASESYNTAX; 435 int saveherefd; 436 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 437 438 INTOFF; 439 saveifs = ifsfirst; 440 savelastp = ifslastp; 441 saveargbackq = argbackq; 442 saveherefd = herefd; 443 herefd = -1; 444 p = grabstackstr(dest); 445 evalbackcmd(cmd, &in); 446 ungrabstackstr(p, dest); 447 ifsfirst = saveifs; 448 ifslastp = savelastp; 449 argbackq = saveargbackq; 450 herefd = saveherefd; 451 452 p = in.buf; 453 lastc = '\0'; 454 for (;;) { 455 if (--in.nleft < 0) { 456 if (in.fd < 0) 457 break; 458 while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR); 459 TRACE(("expbackq: read returns %d\n", i)); 460 if (i <= 0) 461 break; 462 p = buf; 463 in.nleft = i - 1; 464 } 465 lastc = *p++; 466 if (lastc != '\0') { 467 if (quotes && syntax[(int)lastc] == CCTL) 468 STPUTC(CTLESC, dest); 469 STPUTC(lastc, dest); 470 } 471 } 472 473 /* Eat all trailing newlines */ 474 for ( ; (dest - stackblock()) > startloc && *(dest-1) == '\n'; ) 475 STUNPUTC(dest); 476 477 if (in.fd >= 0) 478 close(in.fd); 479 if (in.buf) 480 ckfree(in.buf); 481 if (in.jp) 482 exitstatus = waitforjob(in.jp, (int *)NULL); 483 if (quoted == 0) 484 recordregion(startloc, dest - stackblock(), 0); 485 TRACE(("evalbackq: size=%d: \"%.*s\"\n", 486 (dest - stackblock()) - startloc, 487 (dest - stackblock()) - startloc, 488 stackblock() + startloc)); 489 expdest = dest; 490 INTON; 491 } 492 493 494 495 STATIC int 496 subevalvar(char *p, char *str, int strloc, int subtype, int startloc, 497 int varflags) 498 { 499 char *startp; 500 char *loc = NULL; 501 char *q; 502 int c = 0; 503 int saveherefd = herefd; 504 struct nodelist *saveargbackq = argbackq; 505 int amount; 506 507 herefd = -1; 508 argstr(p, 0); 509 STACKSTRNUL(expdest); 510 herefd = saveherefd; 511 argbackq = saveargbackq; 512 startp = stackblock() + startloc; 513 if (str == NULL) 514 str = stackblock() + strloc; 515 516 switch (subtype) { 517 case VSASSIGN: 518 setvar(str, startp, 0); 519 amount = startp - expdest; 520 STADJUST(amount, expdest); 521 varflags &= ~VSNUL; 522 if (c != 0) 523 *loc = c; 524 return 1; 525 526 case VSQUESTION: 527 if (*p != CTLENDVAR) { 528 outfmt(&errout, "%s\n", startp); 529 error((char *)NULL); 530 } 531 error("%.*s: parameter %snot set", p - str - 1, 532 str, (varflags & VSNUL) ? "null or " 533 : nullstr); 534 return 0; 535 536 case VSTRIMLEFT: 537 for (loc = startp; loc < str; loc++) { 538 c = *loc; 539 *loc = '\0'; 540 if (patmatch(str, startp, varflags & VSQUOTE)) { 541 *loc = c; 542 goto recordleft; 543 } 544 *loc = c; 545 if ((varflags & VSQUOTE) && *loc == CTLESC) 546 loc++; 547 } 548 return 0; 549 550 case VSTRIMLEFTMAX: 551 for (loc = str - 1; loc >= startp;) { 552 c = *loc; 553 *loc = '\0'; 554 if (patmatch(str, startp, varflags & VSQUOTE)) { 555 *loc = c; 556 goto recordleft; 557 } 558 *loc = c; 559 loc--; 560 if ((varflags & VSQUOTE) && loc > startp && 561 *(loc - 1) == CTLESC) { 562 for (q = startp; q < loc; q++) 563 if (*q == CTLESC) 564 q++; 565 if (q > loc) 566 loc--; 567 } 568 } 569 return 0; 570 571 case VSTRIMRIGHT: 572 for (loc = str - 1; loc >= startp;) { 573 if (patmatch(str, loc, varflags & VSQUOTE)) { 574 amount = loc - expdest; 575 STADJUST(amount, expdest); 576 return 1; 577 } 578 loc--; 579 if ((varflags & VSQUOTE) && loc > startp && 580 *(loc - 1) == CTLESC) { 581 for (q = startp; q < loc; q++) 582 if (*q == CTLESC) 583 q++; 584 if (q > loc) 585 loc--; 586 } 587 } 588 return 0; 589 590 case VSTRIMRIGHTMAX: 591 for (loc = startp; loc < str - 1; loc++) { 592 if (patmatch(str, loc, varflags & VSQUOTE)) { 593 amount = loc - expdest; 594 STADJUST(amount, expdest); 595 return 1; 596 } 597 if ((varflags & VSQUOTE) && *loc == CTLESC) 598 loc++; 599 } 600 return 0; 601 602 603 default: 604 abort(); 605 } 606 607 recordleft: 608 amount = ((str - 1) - (loc - startp)) - expdest; 609 STADJUST(amount, expdest); 610 while (loc != str - 1) 611 *startp++ = *loc++; 612 return 1; 613 } 614 615 616 /* 617 * Expand a variable, and return a pointer to the next character in the 618 * input string. 619 */ 620 621 STATIC char * 622 evalvar(char *p, int flag) 623 { 624 int subtype; 625 int varflags; 626 char *var; 627 char *val; 628 int patloc; 629 int c; 630 int set; 631 int special; 632 int startloc; 633 int varlen; 634 int easy; 635 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 636 637 varflags = *p++; 638 subtype = varflags & VSTYPE; 639 var = p; 640 special = 0; 641 if (! is_name(*p)) 642 special = 1; 643 p = strchr(p, '=') + 1; 644 again: /* jump here after setting a variable with ${var=text} */ 645 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", p - var - 1, var); 667 } 668 } 669 if (set && subtype != VSPLUS) { 670 /* insert the value of the variable */ 671 if (special) { 672 varvalue(var, varflags & VSQUOTE, flag & EXP_FULL); 673 if (subtype == VSLENGTH) { 674 varlen = expdest - stackblock() - startloc; 675 STADJUST(-varlen, expdest); 676 } 677 } else { 678 char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX 679 : BASESYNTAX; 680 681 if (subtype == VSLENGTH) { 682 for (;*val; val++) 683 varlen++; 684 } 685 else { 686 while (*val) { 687 if (quotes && 688 syntax[(int)*val] == CCTL) 689 STPUTC(CTLESC, expdest); 690 STPUTC(*val++, expdest); 691 } 692 693 } 694 } 695 } 696 697 if (subtype == VSPLUS) 698 set = ! set; 699 700 easy = ((varflags & VSQUOTE) == 0 || 701 (*var == '@' && shellparam.nparam != 1)); 702 703 704 switch (subtype) { 705 case VSLENGTH: 706 expdest = cvtnum(varlen, expdest); 707 goto record; 708 709 case VSNORMAL: 710 if (!easy) 711 break; 712 record: 713 recordregion(startloc, expdest - stackblock(), 714 varflags & VSQUOTE); 715 break; 716 717 case VSPLUS: 718 case VSMINUS: 719 if (!set) { 720 argstr(p, flag); 721 break; 722 } 723 if (easy) 724 goto record; 725 break; 726 727 case VSTRIMLEFT: 728 case VSTRIMLEFTMAX: 729 case VSTRIMRIGHT: 730 case VSTRIMRIGHTMAX: 731 if (!set) 732 break; 733 /* 734 * Terminate the string and start recording the pattern 735 * right after it 736 */ 737 STPUTC('\0', expdest); 738 patloc = expdest - stackblock(); 739 if (subevalvar(p, NULL, patloc, subtype, 740 startloc, varflags) == 0) { 741 int amount = (expdest - stackblock() - patloc) + 1; 742 STADJUST(-amount, expdest); 743 } 744 /* Remove any recorded regions beyond start of variable */ 745 removerecordregions(startloc); 746 goto record; 747 748 case VSASSIGN: 749 case VSQUESTION: 750 if (!set) { 751 if (subevalvar(p, var, 0, subtype, startloc, varflags)) { 752 varflags &= ~VSNUL; 753 /* 754 * Remove any recorded regions beyond 755 * start of variable 756 */ 757 removerecordregions(startloc); 758 goto again; 759 } 760 break; 761 } 762 if (easy) 763 goto record; 764 break; 765 766 default: 767 abort(); 768 } 769 770 if (subtype != VSNORMAL) { /* skip to end of alternative */ 771 int nesting = 1; 772 for (;;) { 773 if ((c = *p++) == CTLESC) 774 p++; 775 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { 776 if (set) 777 argbackq = argbackq->next; 778 } else if (c == CTLVAR) { 779 if ((*p++ & VSTYPE) != VSNORMAL) 780 nesting++; 781 } else if (c == CTLENDVAR) { 782 if (--nesting == 0) 783 break; 784 } 785 } 786 } 787 return p; 788 } 789 790 791 792 /* 793 * Test whether a specialized variable is set. 794 */ 795 796 STATIC int 797 varisset(char *name, int nulok) 798 { 799 800 if (*name == '!') 801 return backgndpid != -1; 802 else if (*name == '@' || *name == '*') { 803 if (*shellparam.p == NULL) 804 return 0; 805 806 if (nulok) { 807 char **av; 808 809 for (av = shellparam.p; *av; av++) 810 if (**av != '\0') 811 return 1; 812 return 0; 813 } 814 } else if (is_digit(*name)) { 815 char *ap; 816 int num = atoi(name); 817 818 if (num > shellparam.nparam) 819 return 0; 820 821 if (num == 0) 822 ap = arg0; 823 else 824 ap = shellparam.p[num - 1]; 825 826 if (nulok && (ap == NULL || *ap == '\0')) 827 return 0; 828 } 829 return 1; 830 } 831 832 833 834 /* 835 * Add the value of a specialized variable to the stack string. 836 */ 837 838 STATIC void 839 varvalue(char *name, int quoted, int allow_split) 840 { 841 int num; 842 char *p; 843 int i; 844 char sep; 845 char **ap; 846 char const *syntax; 847 848 #define STRTODEST(p) \ 849 do {\ 850 if (allow_split) { \ 851 syntax = quoted? DQSYNTAX : BASESYNTAX; \ 852 while (*p) { \ 853 if (syntax[(int)*p] == CCTL) \ 854 STPUTC(CTLESC, expdest); \ 855 STPUTC(*p++, expdest); \ 856 } \ 857 } else \ 858 while (*p) \ 859 STPUTC(*p++, expdest); \ 860 } while (0) 861 862 863 switch (*name) { 864 case '$': 865 num = rootpid; 866 goto numvar; 867 case '?': 868 num = oexitstatus; 869 goto numvar; 870 case '#': 871 num = shellparam.nparam; 872 goto numvar; 873 case '!': 874 num = backgndpid; 875 numvar: 876 expdest = cvtnum(num, expdest); 877 break; 878 case '-': 879 for (i = 0 ; i < NOPTS ; i++) { 880 if (optlist[i].val) 881 STPUTC(optlist[i].letter, expdest); 882 } 883 break; 884 case '@': 885 if (allow_split && quoted) { 886 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 887 STRTODEST(p); 888 if (*ap) 889 STPUTC('\0', expdest); 890 } 891 break; 892 } 893 /* fall through */ 894 case '*': 895 if (ifsset() != 0) 896 sep = ifsval()[0]; 897 else 898 sep = ' '; 899 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 900 STRTODEST(p); 901 if (*ap && sep) 902 STPUTC(sep, expdest); 903 } 904 break; 905 case '0': 906 p = arg0; 907 STRTODEST(p); 908 break; 909 default: 910 if (is_digit(*name)) { 911 num = atoi(name); 912 if (num > 0 && num <= shellparam.nparam) { 913 p = shellparam.p[num - 1]; 914 STRTODEST(p); 915 } 916 } 917 break; 918 } 919 } 920 921 922 923 /* 924 * Record the the fact that we have to scan this region of the 925 * string for IFS characters. 926 */ 927 928 STATIC void 929 recordregion(int start, int end, int nulonly) 930 { 931 struct ifsregion *ifsp; 932 933 if (ifslastp == NULL) { 934 ifsp = &ifsfirst; 935 } else { 936 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 937 ifslastp->next = ifsp; 938 } 939 ifslastp = ifsp; 940 ifslastp->next = NULL; 941 ifslastp->begoff = start; 942 ifslastp->endoff = end; 943 ifslastp->nulonly = nulonly; 944 } 945 946 947 948 /* 949 * Break the argument string into pieces based upon IFS and add the 950 * strings to the argument list. The regions of the string to be 951 * searched for IFS characters have been stored by recordregion. 952 */ 953 STATIC void 954 ifsbreakup(char *string, struct arglist *arglist) 955 { 956 struct ifsregion *ifsp; 957 struct strlist *sp; 958 char *start; 959 char *p; 960 char *q; 961 const char *ifs; 962 int ifsspc; 963 int nulonly; 964 965 966 start = string; 967 ifsspc = 0; 968 nulonly = 0; 969 if (ifslastp != NULL) { 970 ifsp = &ifsfirst; 971 do { 972 p = string + ifsp->begoff; 973 nulonly = ifsp->nulonly; 974 ifs = nulonly ? nullstr : 975 ( ifsset() ? ifsval() : " \t\n" ); 976 ifsspc = 0; 977 while (p < string + ifsp->endoff) { 978 q = p; 979 if (*p == CTLESC) 980 p++; 981 if (strchr(ifs, *p)) { 982 if (!nulonly) 983 ifsspc = (strchr(" \t\n", *p) != NULL); 984 /* Ignore IFS whitespace at start */ 985 if (q == start && ifsspc) { 986 p++; 987 start = p; 988 continue; 989 } 990 *q = '\0'; 991 sp = (struct strlist *)stalloc(sizeof *sp); 992 sp->text = start; 993 *arglist->lastp = sp; 994 arglist->lastp = &sp->next; 995 p++; 996 if (!nulonly) { 997 for (;;) { 998 if (p >= string + ifsp->endoff) { 999 break; 1000 } 1001 q = p; 1002 if (*p == CTLESC) 1003 p++; 1004 if (strchr(ifs, *p) == NULL ) { 1005 p = q; 1006 break; 1007 } else if (strchr(" \t\n",*p) == NULL) { 1008 if (ifsspc) { 1009 p++; 1010 ifsspc = 0; 1011 } else { 1012 p = q; 1013 break; 1014 } 1015 } else 1016 p++; 1017 } 1018 } 1019 start = p; 1020 } else 1021 p++; 1022 } 1023 } while ((ifsp = ifsp->next) != NULL); 1024 if (*start || (!ifsspc && start > string && 1025 (nulonly || 1))) { 1026 sp = (struct strlist *)stalloc(sizeof *sp); 1027 sp->text = start; 1028 *arglist->lastp = sp; 1029 arglist->lastp = &sp->next; 1030 } 1031 } else { 1032 sp = (struct strlist *)stalloc(sizeof *sp); 1033 sp->text = start; 1034 *arglist->lastp = sp; 1035 arglist->lastp = &sp->next; 1036 } 1037 } 1038 1039 1040 1041 /* 1042 * Expand shell metacharacters. At this point, the only control characters 1043 * should be escapes. The results are stored in the list exparg. 1044 */ 1045 1046 STATIC char *expdir; 1047 1048 1049 STATIC void 1050 expandmeta(struct strlist *str, int flag __unused) 1051 { 1052 char *p; 1053 struct strlist **savelastp; 1054 struct strlist *sp; 1055 char c; 1056 /* TODO - EXP_REDIR */ 1057 1058 while (str) { 1059 if (fflag) 1060 goto nometa; 1061 p = str->text; 1062 for (;;) { /* fast check for meta chars */ 1063 if ((c = *p++) == '\0') 1064 goto nometa; 1065 if (c == '*' || c == '?' || c == '[' || c == '!') 1066 break; 1067 } 1068 savelastp = exparg.lastp; 1069 INTOFF; 1070 if (expdir == NULL) { 1071 int i = strlen(str->text); 1072 expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */ 1073 } 1074 1075 expmeta(expdir, str->text); 1076 ckfree(expdir); 1077 expdir = NULL; 1078 INTON; 1079 if (exparg.lastp == savelastp) { 1080 /* 1081 * no matches 1082 */ 1083 nometa: 1084 *exparg.lastp = str; 1085 rmescapes(str->text); 1086 exparg.lastp = &str->next; 1087 } else { 1088 *exparg.lastp = NULL; 1089 *savelastp = sp = expsort(*savelastp); 1090 while (sp->next != NULL) 1091 sp = sp->next; 1092 exparg.lastp = &sp->next; 1093 } 1094 str = str->next; 1095 } 1096 } 1097 1098 1099 /* 1100 * Do metacharacter (i.e. *, ?, [...]) expansion. 1101 */ 1102 1103 STATIC void 1104 expmeta(char *enddir, char *name) 1105 { 1106 char *p; 1107 const char *q; 1108 char *start; 1109 char *endname; 1110 int metaflag; 1111 struct stat statb; 1112 DIR *dirp; 1113 struct dirent *dp; 1114 int atend; 1115 int matchdot; 1116 1117 metaflag = 0; 1118 start = name; 1119 for (p = name ; ; p++) { 1120 if (*p == '*' || *p == '?') 1121 metaflag = 1; 1122 else if (*p == '[') { 1123 q = p + 1; 1124 if (*q == '!' || *q == '^') 1125 q++; 1126 for (;;) { 1127 while (*q == CTLQUOTEMARK) 1128 q++; 1129 if (*q == CTLESC) 1130 q++; 1131 if (*q == '/' || *q == '\0') 1132 break; 1133 if (*++q == ']') { 1134 metaflag = 1; 1135 break; 1136 } 1137 } 1138 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 1139 metaflag = 1; 1140 } else if (*p == '\0') 1141 break; 1142 else if (*p == CTLQUOTEMARK) 1143 continue; 1144 else if (*p == CTLESC) 1145 p++; 1146 if (*p == '/') { 1147 if (metaflag) 1148 break; 1149 start = p + 1; 1150 } 1151 } 1152 if (metaflag == 0) { /* we've reached the end of the file name */ 1153 if (enddir != expdir) 1154 metaflag++; 1155 for (p = name ; ; p++) { 1156 if (*p == CTLQUOTEMARK) 1157 continue; 1158 if (*p == CTLESC) 1159 p++; 1160 *enddir++ = *p; 1161 if (*p == '\0') 1162 break; 1163 } 1164 if (metaflag == 0 || lstat(expdir, &statb) >= 0) 1165 addfname(expdir); 1166 return; 1167 } 1168 endname = p; 1169 if (start != name) { 1170 p = name; 1171 while (p < start) { 1172 while (*p == CTLQUOTEMARK) 1173 p++; 1174 if (*p == CTLESC) 1175 p++; 1176 *enddir++ = *p++; 1177 } 1178 } 1179 if (enddir == expdir) { 1180 q = "."; 1181 } else if (enddir == expdir + 1 && *expdir == '/') { 1182 q = "/"; 1183 } else { 1184 q = expdir; 1185 enddir[-1] = '\0'; 1186 } 1187 if ((dirp = opendir(q)) == NULL) 1188 return; 1189 if (enddir != expdir) 1190 enddir[-1] = '/'; 1191 if (*endname == 0) { 1192 atend = 1; 1193 } else { 1194 atend = 0; 1195 *endname++ = '\0'; 1196 } 1197 matchdot = 0; 1198 p = start; 1199 while (*p == CTLQUOTEMARK) 1200 p++; 1201 if (*p == CTLESC) 1202 p++; 1203 if (*p == '.') 1204 matchdot++; 1205 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 1206 if (dp->d_name[0] == '.' && ! matchdot) 1207 continue; 1208 if (patmatch(start, dp->d_name, 0)) { 1209 if (atend) { 1210 scopy(dp->d_name, enddir); 1211 addfname(expdir); 1212 } else { 1213 char *t; 1214 for (t = enddir, q = dp->d_name; 1215 (*t++ = *q++) != '\0';) 1216 continue; 1217 t[-1] = '/'; 1218 expmeta(t, endname); 1219 } 1220 } 1221 } 1222 closedir(dirp); 1223 if (! atend) 1224 endname[-1] = '/'; 1225 } 1226 1227 1228 /* 1229 * Add a file name to the list. 1230 */ 1231 1232 STATIC void 1233 addfname(char *name) 1234 { 1235 char *p; 1236 struct strlist *sp; 1237 1238 p = stalloc(strlen(name) + 1); 1239 scopy(name, p); 1240 sp = (struct strlist *)stalloc(sizeof *sp); 1241 sp->text = p; 1242 *exparg.lastp = sp; 1243 exparg.lastp = &sp->next; 1244 } 1245 1246 1247 /* 1248 * Sort the results of file name expansion. It calculates the number of 1249 * strings to sort and then calls msort (short for merge sort) to do the 1250 * work. 1251 */ 1252 1253 STATIC struct strlist * 1254 expsort(struct strlist *str) 1255 { 1256 int len; 1257 struct strlist *sp; 1258 1259 len = 0; 1260 for (sp = str ; sp ; sp = sp->next) 1261 len++; 1262 return msort(str, len); 1263 } 1264 1265 1266 STATIC struct strlist * 1267 msort(struct strlist *list, int len) 1268 { 1269 struct strlist *p, *q = NULL; 1270 struct strlist **lpp; 1271 int half; 1272 int n; 1273 1274 if (len <= 1) 1275 return list; 1276 half = len >> 1; 1277 p = list; 1278 for (n = half ; --n >= 0 ; ) { 1279 q = p; 1280 p = p->next; 1281 } 1282 q->next = NULL; /* terminate first half of list */ 1283 q = msort(list, half); /* sort first half of list */ 1284 p = msort(p, len - half); /* sort second half */ 1285 lpp = &list; 1286 for (;;) { 1287 if (strcmp(p->text, q->text) < 0) { 1288 *lpp = p; 1289 lpp = &p->next; 1290 if ((p = *lpp) == NULL) { 1291 *lpp = q; 1292 break; 1293 } 1294 } else { 1295 *lpp = q; 1296 lpp = &q->next; 1297 if ((q = *lpp) == NULL) { 1298 *lpp = p; 1299 break; 1300 } 1301 } 1302 } 1303 return list; 1304 } 1305 1306 1307 1308 /* 1309 * Returns true if the pattern matches the string. 1310 */ 1311 1312 int 1313 patmatch(char *pattern, char *string, int squoted) 1314 { 1315 #ifdef notdef 1316 if (pattern[0] == '!' && pattern[1] == '!') 1317 return 1 - pmatch(pattern + 2, string); 1318 else 1319 #endif 1320 return pmatch(pattern, string, squoted); 1321 } 1322 1323 1324 STATIC int 1325 pmatch(char *pattern, char *string, int squoted) 1326 { 1327 char *p, *q; 1328 char c; 1329 1330 p = pattern; 1331 q = string; 1332 for (;;) { 1333 switch (c = *p++) { 1334 case '\0': 1335 goto breakloop; 1336 case CTLESC: 1337 if (squoted && *q == CTLESC) 1338 q++; 1339 if (*q++ != *p++) 1340 return 0; 1341 break; 1342 case CTLQUOTEMARK: 1343 continue; 1344 case '?': 1345 if (squoted && *q == CTLESC) 1346 q++; 1347 if (*q++ == '\0') 1348 return 0; 1349 break; 1350 case '*': 1351 c = *p; 1352 while (c == CTLQUOTEMARK || c == '*') 1353 c = *++p; 1354 if (c != CTLESC && c != CTLQUOTEMARK && 1355 c != '?' && c != '*' && c != '[') { 1356 while (*q != c) { 1357 if (squoted && *q == CTLESC && 1358 q[1] == c) 1359 break; 1360 if (*q == '\0') 1361 return 0; 1362 if (squoted && *q == CTLESC) 1363 q++; 1364 q++; 1365 } 1366 } 1367 do { 1368 if (pmatch(p, q, squoted)) 1369 return 1; 1370 if (squoted && *q == CTLESC) 1371 q++; 1372 } while (*q++ != '\0'); 1373 return 0; 1374 case '[': { 1375 char *endp; 1376 int invert, found; 1377 char chr; 1378 1379 endp = p; 1380 if (*endp == '!' || *endp == '^') 1381 endp++; 1382 for (;;) { 1383 while (*endp == CTLQUOTEMARK) 1384 endp++; 1385 if (*endp == '\0') 1386 goto dft; /* no matching ] */ 1387 if (*endp == CTLESC) 1388 endp++; 1389 if (*++endp == ']') 1390 break; 1391 } 1392 invert = 0; 1393 if (*p == '!' || *p == '^') { 1394 invert++; 1395 p++; 1396 } 1397 found = 0; 1398 chr = *q++; 1399 if (squoted && chr == CTLESC) 1400 chr = *q++; 1401 if (chr == '\0') 1402 return 0; 1403 c = *p++; 1404 do { 1405 if (c == CTLQUOTEMARK) 1406 continue; 1407 if (c == CTLESC) 1408 c = *p++; 1409 if (*p == '-' && p[1] != ']') { 1410 p++; 1411 while (*p == CTLQUOTEMARK) 1412 p++; 1413 if (*p == CTLESC) 1414 p++; 1415 if ( collate_range_cmp(chr, c) >= 0 1416 && collate_range_cmp(chr, *p) <= 0 1417 ) 1418 found = 1; 1419 p++; 1420 } else { 1421 if (chr == c) 1422 found = 1; 1423 } 1424 } while ((c = *p++) != ']'); 1425 if (found == invert) 1426 return 0; 1427 break; 1428 } 1429 dft: default: 1430 if (squoted && *q == CTLESC) 1431 q++; 1432 if (*q++ != c) 1433 return 0; 1434 break; 1435 } 1436 } 1437 breakloop: 1438 if (*q != '\0') 1439 return 0; 1440 return 1; 1441 } 1442 1443 1444 1445 /* 1446 * Remove any CTLESC characters from a string. 1447 */ 1448 1449 void 1450 rmescapes(char *str) 1451 { 1452 char *p, *q; 1453 1454 p = str; 1455 while (*p != CTLESC && *p != CTLQUOTEMARK) { 1456 if (*p++ == '\0') 1457 return; 1458 } 1459 q = p; 1460 while (*p) { 1461 if (*p == CTLQUOTEMARK) { 1462 p++; 1463 continue; 1464 } 1465 if (*p == CTLESC) 1466 p++; 1467 *q++ = *p++; 1468 } 1469 *q = '\0'; 1470 } 1471 1472 1473 1474 /* 1475 * See if a pattern matches in a case statement. 1476 */ 1477 1478 int 1479 casematch(union node *pattern, char *val) 1480 { 1481 struct stackmark smark; 1482 int result; 1483 char *p; 1484 1485 setstackmark(&smark); 1486 argbackq = pattern->narg.backquote; 1487 STARTSTACKSTR(expdest); 1488 ifslastp = NULL; 1489 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); 1490 STPUTC('\0', expdest); 1491 p = grabstackstr(expdest); 1492 result = patmatch(p, val, 0); 1493 popstackmark(&smark); 1494 return result; 1495 } 1496 1497 /* 1498 * Our own itoa(). 1499 */ 1500 1501 STATIC char * 1502 cvtnum(int num, char *buf) 1503 { 1504 char temp[32]; 1505 int neg = num < 0; 1506 char *p = temp + 31; 1507 1508 temp[31] = '\0'; 1509 1510 do { 1511 *--p = num % 10 + '0'; 1512 } while ((num /= 10) != 0); 1513 1514 if (neg) 1515 *--p = '-'; 1516 1517 while (*p) 1518 STPUTC(*p++, buf); 1519 return buf; 1520 } 1521