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, (struct arglist *)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, (int *)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((char *)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 (special) { 640 set = varisset(var, varflags & VSNUL); 641 val = NULL; 642 } else { 643 val = bltinlookup(var, 1); 644 if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) { 645 val = NULL; 646 set = 0; 647 } else 648 set = 1; 649 } 650 varlen = 0; 651 startloc = expdest - stackblock(); 652 if (!set && uflag) { 653 switch (subtype) { 654 case VSNORMAL: 655 case VSTRIMLEFT: 656 case VSTRIMLEFTMAX: 657 case VSTRIMRIGHT: 658 case VSTRIMRIGHTMAX: 659 case VSLENGTH: 660 error("%.*s: parameter not set", (int)(p - var - 1), 661 var); 662 } 663 } 664 if (set && subtype != VSPLUS) { 665 /* insert the value of the variable */ 666 if (special) { 667 varvalue(var, varflags & VSQUOTE, subtype, flag); 668 if (subtype == VSLENGTH) { 669 varlen = expdest - stackblock() - startloc; 670 STADJUST(-varlen, expdest); 671 } 672 } else { 673 char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX 674 : BASESYNTAX; 675 676 if (subtype == VSLENGTH) { 677 for (;*val; val++) 678 varlen++; 679 } 680 else { 681 while (*val) { 682 if (quotes && 683 syntax[(int)*val] == CCTL) 684 STPUTC(CTLESC, expdest); 685 STPUTC(*val++, expdest); 686 } 687 688 } 689 } 690 } 691 692 if (subtype == VSPLUS) 693 set = ! set; 694 695 easy = ((varflags & VSQUOTE) == 0 || 696 (*var == '@' && shellparam.nparam != 1)); 697 698 699 switch (subtype) { 700 case VSLENGTH: 701 expdest = cvtnum(varlen, expdest); 702 goto record; 703 704 case VSNORMAL: 705 if (!easy) 706 break; 707 record: 708 recordregion(startloc, expdest - stackblock(), 709 varflags & VSQUOTE); 710 break; 711 712 case VSPLUS: 713 case VSMINUS: 714 if (!set) { 715 argstr(p, flag); 716 break; 717 } 718 if (easy) 719 goto record; 720 break; 721 722 case VSTRIMLEFT: 723 case VSTRIMLEFTMAX: 724 case VSTRIMRIGHT: 725 case VSTRIMRIGHTMAX: 726 if (!set) 727 break; 728 /* 729 * Terminate the string and start recording the pattern 730 * right after it 731 */ 732 STPUTC('\0', expdest); 733 patloc = expdest - stackblock(); 734 if (subevalvar(p, NULL, patloc, subtype, 735 startloc, varflags) == 0) { 736 int amount = (expdest - stackblock() - patloc) + 1; 737 STADJUST(-amount, expdest); 738 } 739 /* Remove any recorded regions beyond start of variable */ 740 removerecordregions(startloc); 741 goto record; 742 743 case VSASSIGN: 744 case VSQUESTION: 745 if (!set) { 746 if (subevalvar(p, var, 0, subtype, startloc, varflags)) { 747 varflags &= ~VSNUL; 748 /* 749 * Remove any recorded regions beyond 750 * start of variable 751 */ 752 removerecordregions(startloc); 753 goto again; 754 } 755 break; 756 } 757 if (easy) 758 goto record; 759 break; 760 761 case VSERROR: 762 c = p - var - 1; 763 error("${%.*s%s}: Bad substitution", c, var, 764 (c > 0 && *p != CTLENDVAR) ? "..." : ""); 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 subtype, int flag) 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 (flag & (EXP_FULL | EXP_CASE) && subtype != VSLENGTH) { \ 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 (flag & EXP_FULL && quoted) { 886 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 887 STRTODEST(p); 888 if (*ap) 889 STPUTC('\0', expdest); 890 } 891 break; 892 } 893 /* FALLTHROUGH */ 894 case '*': 895 if (ifsset()) 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 sp = (struct strlist *)stalloc(sizeof *sp); 1026 sp->text = start; 1027 *arglist->lastp = sp; 1028 arglist->lastp = &sp->next; 1029 } 1030 } else { 1031 sp = (struct strlist *)stalloc(sizeof *sp); 1032 sp->text = start; 1033 *arglist->lastp = sp; 1034 arglist->lastp = &sp->next; 1035 } 1036 } 1037 1038 1039 1040 /* 1041 * Expand shell metacharacters. At this point, the only control characters 1042 * should be escapes. The results are stored in the list exparg. 1043 */ 1044 1045 STATIC char *expdir; 1046 1047 1048 STATIC void 1049 expandmeta(struct strlist *str, int flag __unused) 1050 { 1051 char *p; 1052 struct strlist **savelastp; 1053 struct strlist *sp; 1054 char c; 1055 /* TODO - EXP_REDIR */ 1056 1057 while (str) { 1058 if (fflag) 1059 goto nometa; 1060 p = str->text; 1061 for (;;) { /* fast check for meta chars */ 1062 if ((c = *p++) == '\0') 1063 goto nometa; 1064 if (c == '*' || c == '?' || c == '[' || c == '!') 1065 break; 1066 } 1067 savelastp = exparg.lastp; 1068 INTOFF; 1069 if (expdir == NULL) { 1070 int i = strlen(str->text); 1071 expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */ 1072 } 1073 1074 expmeta(expdir, str->text); 1075 ckfree(expdir); 1076 expdir = NULL; 1077 INTON; 1078 if (exparg.lastp == savelastp) { 1079 /* 1080 * no matches 1081 */ 1082 nometa: 1083 *exparg.lastp = str; 1084 rmescapes(str->text); 1085 exparg.lastp = &str->next; 1086 } else { 1087 *exparg.lastp = NULL; 1088 *savelastp = sp = expsort(*savelastp); 1089 while (sp->next != NULL) 1090 sp = sp->next; 1091 exparg.lastp = &sp->next; 1092 } 1093 str = str->next; 1094 } 1095 } 1096 1097 1098 /* 1099 * Do metacharacter (i.e. *, ?, [...]) expansion. 1100 */ 1101 1102 STATIC void 1103 expmeta(char *enddir, char *name) 1104 { 1105 char *p; 1106 const char *q; 1107 char *start; 1108 char *endname; 1109 int metaflag; 1110 struct stat statb; 1111 DIR *dirp; 1112 struct dirent *dp; 1113 int atend; 1114 int matchdot; 1115 1116 metaflag = 0; 1117 start = name; 1118 for (p = name ; ; p++) { 1119 if (*p == '*' || *p == '?') 1120 metaflag = 1; 1121 else if (*p == '[') { 1122 q = p + 1; 1123 if (*q == '!' || *q == '^') 1124 q++; 1125 for (;;) { 1126 while (*q == CTLQUOTEMARK) 1127 q++; 1128 if (*q == CTLESC) 1129 q++; 1130 if (*q == '/' || *q == '\0') 1131 break; 1132 if (*++q == ']') { 1133 metaflag = 1; 1134 break; 1135 } 1136 } 1137 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 1138 metaflag = 1; 1139 } else if (*p == '\0') 1140 break; 1141 else if (*p == CTLQUOTEMARK) 1142 continue; 1143 else if (*p == CTLESC) 1144 p++; 1145 if (*p == '/') { 1146 if (metaflag) 1147 break; 1148 start = p + 1; 1149 } 1150 } 1151 if (metaflag == 0) { /* we've reached the end of the file name */ 1152 if (enddir != expdir) 1153 metaflag++; 1154 for (p = name ; ; p++) { 1155 if (*p == CTLQUOTEMARK) 1156 continue; 1157 if (*p == CTLESC) 1158 p++; 1159 *enddir++ = *p; 1160 if (*p == '\0') 1161 break; 1162 } 1163 if (metaflag == 0 || lstat(expdir, &statb) >= 0) 1164 addfname(expdir); 1165 return; 1166 } 1167 endname = p; 1168 if (start != name) { 1169 p = name; 1170 while (p < start) { 1171 while (*p == CTLQUOTEMARK) 1172 p++; 1173 if (*p == CTLESC) 1174 p++; 1175 *enddir++ = *p++; 1176 } 1177 } 1178 if (enddir == expdir) { 1179 q = "."; 1180 } else if (enddir == expdir + 1 && *expdir == '/') { 1181 q = "/"; 1182 } else { 1183 q = expdir; 1184 enddir[-1] = '\0'; 1185 } 1186 if ((dirp = opendir(q)) == NULL) 1187 return; 1188 if (enddir != expdir) 1189 enddir[-1] = '/'; 1190 if (*endname == 0) { 1191 atend = 1; 1192 } else { 1193 atend = 0; 1194 *endname++ = '\0'; 1195 } 1196 matchdot = 0; 1197 p = start; 1198 while (*p == CTLQUOTEMARK) 1199 p++; 1200 if (*p == CTLESC) 1201 p++; 1202 if (*p == '.') 1203 matchdot++; 1204 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 1205 if (dp->d_name[0] == '.' && ! matchdot) 1206 continue; 1207 if (patmatch(start, dp->d_name, 0)) { 1208 if (atend) { 1209 scopy(dp->d_name, enddir); 1210 addfname(expdir); 1211 } else { 1212 char *t; 1213 for (t = enddir, q = dp->d_name; 1214 (*t++ = *q++) != '\0';) 1215 continue; 1216 t[-1] = '/'; 1217 expmeta(t, endname); 1218 } 1219 } 1220 } 1221 closedir(dirp); 1222 if (! atend) 1223 endname[-1] = '/'; 1224 } 1225 1226 1227 /* 1228 * Add a file name to the list. 1229 */ 1230 1231 STATIC void 1232 addfname(char *name) 1233 { 1234 char *p; 1235 struct strlist *sp; 1236 1237 p = stalloc(strlen(name) + 1); 1238 scopy(name, p); 1239 sp = (struct strlist *)stalloc(sizeof *sp); 1240 sp->text = p; 1241 *exparg.lastp = sp; 1242 exparg.lastp = &sp->next; 1243 } 1244 1245 1246 /* 1247 * Sort the results of file name expansion. It calculates the number of 1248 * strings to sort and then calls msort (short for merge sort) to do the 1249 * work. 1250 */ 1251 1252 STATIC struct strlist * 1253 expsort(struct strlist *str) 1254 { 1255 int len; 1256 struct strlist *sp; 1257 1258 len = 0; 1259 for (sp = str ; sp ; sp = sp->next) 1260 len++; 1261 return msort(str, len); 1262 } 1263 1264 1265 STATIC struct strlist * 1266 msort(struct strlist *list, int len) 1267 { 1268 struct strlist *p, *q = NULL; 1269 struct strlist **lpp; 1270 int half; 1271 int n; 1272 1273 if (len <= 1) 1274 return list; 1275 half = len >> 1; 1276 p = list; 1277 for (n = half ; --n >= 0 ; ) { 1278 q = p; 1279 p = p->next; 1280 } 1281 q->next = NULL; /* terminate first half of list */ 1282 q = msort(list, half); /* sort first half of list */ 1283 p = msort(p, len - half); /* sort second half */ 1284 lpp = &list; 1285 for (;;) { 1286 if (strcmp(p->text, q->text) < 0) { 1287 *lpp = p; 1288 lpp = &p->next; 1289 if ((p = *lpp) == NULL) { 1290 *lpp = q; 1291 break; 1292 } 1293 } else { 1294 *lpp = q; 1295 lpp = &q->next; 1296 if ((q = *lpp) == NULL) { 1297 *lpp = p; 1298 break; 1299 } 1300 } 1301 } 1302 return list; 1303 } 1304 1305 1306 1307 /* 1308 * Returns true if the pattern matches the string. 1309 */ 1310 1311 int 1312 patmatch(char *pattern, char *string, int squoted) 1313 { 1314 #ifdef notdef 1315 if (pattern[0] == '!' && pattern[1] == '!') 1316 return 1 - pmatch(pattern + 2, string); 1317 else 1318 #endif 1319 return pmatch(pattern, string, squoted); 1320 } 1321 1322 1323 STATIC int 1324 pmatch(char *pattern, char *string, int squoted) 1325 { 1326 char *p, *q; 1327 char c; 1328 1329 p = pattern; 1330 q = string; 1331 for (;;) { 1332 switch (c = *p++) { 1333 case '\0': 1334 goto breakloop; 1335 case CTLESC: 1336 if (squoted && *q == CTLESC) 1337 q++; 1338 if (*q++ != *p++) 1339 return 0; 1340 break; 1341 case CTLQUOTEMARK: 1342 continue; 1343 case '?': 1344 if (squoted && *q == CTLESC) 1345 q++; 1346 if (*q++ == '\0') 1347 return 0; 1348 break; 1349 case '*': 1350 c = *p; 1351 while (c == CTLQUOTEMARK || c == '*') 1352 c = *++p; 1353 if (c != CTLESC && c != CTLQUOTEMARK && 1354 c != '?' && c != '*' && c != '[') { 1355 while (*q != c) { 1356 if (squoted && *q == CTLESC && 1357 q[1] == c) 1358 break; 1359 if (*q == '\0') 1360 return 0; 1361 if (squoted && *q == CTLESC) 1362 q++; 1363 q++; 1364 } 1365 } 1366 do { 1367 if (pmatch(p, q, squoted)) 1368 return 1; 1369 if (squoted && *q == CTLESC) 1370 q++; 1371 } while (*q++ != '\0'); 1372 return 0; 1373 case '[': { 1374 char *endp; 1375 int invert, found; 1376 char chr; 1377 1378 endp = p; 1379 if (*endp == '!' || *endp == '^') 1380 endp++; 1381 for (;;) { 1382 while (*endp == CTLQUOTEMARK) 1383 endp++; 1384 if (*endp == '\0') 1385 goto dft; /* no matching ] */ 1386 if (*endp == CTLESC) 1387 endp++; 1388 if (*++endp == ']') 1389 break; 1390 } 1391 invert = 0; 1392 if (*p == '!' || *p == '^') { 1393 invert++; 1394 p++; 1395 } 1396 found = 0; 1397 chr = *q++; 1398 if (squoted && chr == CTLESC) 1399 chr = *q++; 1400 if (chr == '\0') 1401 return 0; 1402 c = *p++; 1403 do { 1404 if (c == CTLQUOTEMARK) 1405 continue; 1406 if (c == CTLESC) 1407 c = *p++; 1408 if (*p == '-' && p[1] != ']') { 1409 p++; 1410 while (*p == CTLQUOTEMARK) 1411 p++; 1412 if (*p == CTLESC) 1413 p++; 1414 if ( collate_range_cmp(chr, c) >= 0 1415 && collate_range_cmp(chr, *p) <= 0 1416 ) 1417 found = 1; 1418 p++; 1419 } else { 1420 if (chr == c) 1421 found = 1; 1422 } 1423 } while ((c = *p++) != ']'); 1424 if (found == invert) 1425 return 0; 1426 break; 1427 } 1428 dft: default: 1429 if (squoted && *q == CTLESC) 1430 q++; 1431 if (*q++ != c) 1432 return 0; 1433 break; 1434 } 1435 } 1436 breakloop: 1437 if (*q != '\0') 1438 return 0; 1439 return 1; 1440 } 1441 1442 1443 1444 /* 1445 * Remove any CTLESC characters from a string. 1446 */ 1447 1448 void 1449 rmescapes(char *str) 1450 { 1451 char *p, *q; 1452 1453 p = str; 1454 while (*p != CTLESC && *p != CTLQUOTEMARK) { 1455 if (*p++ == '\0') 1456 return; 1457 } 1458 q = p; 1459 while (*p) { 1460 if (*p == CTLQUOTEMARK) { 1461 p++; 1462 continue; 1463 } 1464 if (*p == CTLESC) 1465 p++; 1466 *q++ = *p++; 1467 } 1468 *q = '\0'; 1469 } 1470 1471 1472 1473 /* 1474 * See if a pattern matches in a case statement. 1475 */ 1476 1477 int 1478 casematch(union node *pattern, char *val) 1479 { 1480 struct stackmark smark; 1481 int result; 1482 char *p; 1483 1484 setstackmark(&smark); 1485 argbackq = pattern->narg.backquote; 1486 STARTSTACKSTR(expdest); 1487 ifslastp = NULL; 1488 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); 1489 STPUTC('\0', expdest); 1490 p = grabstackstr(expdest); 1491 result = patmatch(p, val, 0); 1492 popstackmark(&smark); 1493 return result; 1494 } 1495 1496 /* 1497 * Our own itoa(). 1498 */ 1499 1500 STATIC char * 1501 cvtnum(int num, char *buf) 1502 { 1503 char temp[32]; 1504 int neg = num < 0; 1505 char *p = temp + 31; 1506 1507 temp[31] = '\0'; 1508 1509 do { 1510 *--p = num % 10 + '0'; 1511 } while ((num /= 10) != 0); 1512 1513 if (neg) 1514 *--p = '-'; 1515 1516 while (*p) 1517 STPUTC(*p++, buf); 1518 return buf; 1519 } 1520 1521 /* 1522 * Do most of the work for wordexp(3). 1523 */ 1524 1525 int 1526 wordexpcmd(int argc, char **argv) 1527 { 1528 size_t len; 1529 int i; 1530 1531 out1fmt("%08x", argc - 1); 1532 for (i = 1, len = 0; i < argc; i++) 1533 len += strlen(argv[i]); 1534 out1fmt("%08x", (int)len); 1535 for (i = 1; i < argc; i++) { 1536 out1str(argv[i]); 1537 out1c('\0'); 1538 } 1539 return (0); 1540 } 1541