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 37 #ifndef lint 38 #if 0 39 static char sccsid[] = "@(#)expand.c 8.5 (Berkeley) 5/15/95"; 40 #endif 41 static const char rcsid[] = 42 "$Id: expand.c,v 1.23 1998/09/06 21:13:09 tegge Exp $"; 43 #endif /* not lint */ 44 45 #include <sys/types.h> 46 #include <sys/time.h> 47 #include <sys/stat.h> 48 #include <errno.h> 49 #include <dirent.h> 50 #include <unistd.h> 51 #include <pwd.h> 52 #include <stdlib.h> 53 #include <limits.h> 54 #include <stdio.h> 55 56 /* 57 * Routines to expand arguments to commands. We have to deal with 58 * backquotes, shell variables, and file metacharacters. 59 */ 60 61 #include "shell.h" 62 #include "main.h" 63 #include "nodes.h" 64 #include "eval.h" 65 #include "expand.h" 66 #include "syntax.h" 67 #include "parser.h" 68 #include "jobs.h" 69 #include "options.h" 70 #include "var.h" 71 #include "input.h" 72 #include "output.h" 73 #include "memalloc.h" 74 #include "error.h" 75 #include "mystring.h" 76 #include "arith.h" 77 #include "show.h" 78 79 /* 80 * Structure specifying which parts of the string should be searched 81 * for IFS characters. 82 */ 83 84 struct ifsregion { 85 struct ifsregion *next; /* next region in list */ 86 int begoff; /* offset of start of region */ 87 int endoff; /* offset of end of region */ 88 int nulonly; /* search for nul bytes only */ 89 }; 90 91 92 char *expdest; /* output of current string */ 93 struct nodelist *argbackq; /* list of back quote expressions */ 94 struct ifsregion ifsfirst; /* first struct in list of ifs regions */ 95 struct ifsregion *ifslastp; /* last struct in list */ 96 struct arglist exparg; /* holds expanded arg list */ 97 98 STATIC void argstr __P((char *, int)); 99 STATIC char *exptilde __P((char *, int)); 100 STATIC void expbackq __P((union node *, int, int)); 101 STATIC int subevalvar __P((char *, char *, int, int, int, int)); 102 STATIC char *evalvar __P((char *, int)); 103 STATIC int varisset __P((char *, int)); 104 STATIC void varvalue __P((char *, int, int)); 105 STATIC void recordregion __P((int, int, int)); 106 STATIC void removerecordregions __P((int)); 107 STATIC void ifsbreakup __P((char *, struct arglist *)); 108 STATIC void expandmeta __P((struct strlist *, int)); 109 STATIC void expmeta __P((char *, char *)); 110 STATIC void addfname __P((char *)); 111 STATIC struct strlist *expsort __P((struct strlist *)); 112 STATIC struct strlist *msort __P((struct strlist *, int)); 113 STATIC int pmatch __P((char *, char *)); 114 STATIC char *cvtnum __P((int, char *)); 115 STATIC int collate_range_cmp __P((int, int)); 116 117 STATIC int collate_range_cmp (c1, c2) 118 int c1, c2; 119 { 120 static char s1[2], s2[2]; 121 int ret; 122 123 c1 &= UCHAR_MAX; 124 c2 &= UCHAR_MAX; 125 if (c1 == c2) 126 return (0); 127 s1[0] = c1; 128 s2[0] = c2; 129 if ((ret = strcoll(s1, s2)) != 0) 130 return (ret); 131 return (c1 - c2); 132 } 133 134 /* 135 * Expand shell variables and backquotes inside a here document. 136 */ 137 138 void 139 expandhere(arg, fd) 140 union node *arg; /* the document */ 141 int fd; /* where to write the expanded version */ 142 { 143 herefd = fd; 144 expandarg(arg, (struct arglist *)NULL, 0); 145 xwrite(fd, stackblock(), expdest - stackblock()); 146 } 147 148 149 /* 150 * Perform variable substitution and command substitution on an argument, 151 * placing the resulting list of arguments in arglist. If EXP_FULL is true, 152 * perform splitting and file name expansion. When arglist is NULL, perform 153 * here document expansion. 154 */ 155 156 void 157 expandarg(arg, arglist, flag) 158 union node *arg; 159 struct arglist *arglist; 160 int flag; 161 { 162 struct strlist *sp; 163 char *p; 164 165 argbackq = arg->narg.backquote; 166 STARTSTACKSTR(expdest); 167 ifsfirst.next = NULL; 168 ifslastp = NULL; 169 argstr(arg->narg.text, flag); 170 if (arglist == NULL) { 171 return; /* here document expanded */ 172 } 173 STPUTC('\0', expdest); 174 p = grabstackstr(expdest); 175 exparg.lastp = &exparg.list; 176 /* 177 * TODO - EXP_REDIR 178 */ 179 if (flag & EXP_FULL) { 180 ifsbreakup(p, &exparg); 181 *exparg.lastp = NULL; 182 exparg.lastp = &exparg.list; 183 expandmeta(exparg.list, flag); 184 } else { 185 if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */ 186 rmescapes(p); 187 sp = (struct strlist *)stalloc(sizeof (struct strlist)); 188 sp->text = p; 189 *exparg.lastp = sp; 190 exparg.lastp = &sp->next; 191 } 192 while (ifsfirst.next != NULL) { 193 struct ifsregion *ifsp; 194 INTOFF; 195 ifsp = ifsfirst.next->next; 196 ckfree(ifsfirst.next); 197 ifsfirst.next = ifsp; 198 INTON; 199 } 200 *exparg.lastp = NULL; 201 if (exparg.list) { 202 *arglist->lastp = exparg.list; 203 arglist->lastp = exparg.lastp; 204 } 205 } 206 207 208 209 /* 210 * Perform variable and command substitution. If EXP_FULL is set, output CTLESC 211 * characters to allow for further processing. Otherwise treat 212 * $@ like $* since no splitting will be performed. 213 */ 214 215 STATIC void 216 argstr(p, flag) 217 char *p; 218 int flag; 219 { 220 char c; 221 int quotes = flag & (EXP_FULL | EXP_CASE); /* do CTLESC */ 222 int firsteq = 1; 223 224 if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE))) 225 p = exptilde(p, flag); 226 for (;;) { 227 switch (c = *p++) { 228 case '\0': 229 case CTLENDVAR: /* ??? */ 230 goto breakloop; 231 case CTLQUOTEMARK: 232 /* "$@" syntax adherence hack */ 233 if (p[0] == CTLVAR && p[2] == '@' && p[3] == '=') 234 break; 235 if ((flag & EXP_FULL) != 0) 236 STPUTC(c, expdest); 237 break; 238 case CTLESC: 239 if (quotes) 240 STPUTC(c, expdest); 241 c = *p++; 242 STPUTC(c, expdest); 243 break; 244 case CTLVAR: 245 p = evalvar(p, flag); 246 break; 247 case CTLBACKQ: 248 case CTLBACKQ|CTLQUOTE: 249 expbackq(argbackq->n, c & CTLQUOTE, flag); 250 argbackq = argbackq->next; 251 break; 252 case CTLENDARI: 253 expari(flag); 254 break; 255 case ':': 256 case '=': 257 /* 258 * sort of a hack - expand tildes in variable 259 * assignments (after the first '=' and after ':'s). 260 */ 261 STPUTC(c, expdest); 262 if (flag & EXP_VARTILDE && *p == '~') { 263 if (c == '=') { 264 if (firsteq) 265 firsteq = 0; 266 else 267 break; 268 } 269 p = exptilde(p, flag); 270 } 271 break; 272 default: 273 STPUTC(c, expdest); 274 } 275 } 276 breakloop:; 277 } 278 279 STATIC char * 280 exptilde(p, flag) 281 char *p; 282 int flag; 283 { 284 char c, *startp = p; 285 struct passwd *pw; 286 char *home; 287 int quotes = flag & (EXP_FULL | EXP_CASE); 288 289 while ((c = *p) != '\0') { 290 switch(c) { 291 case CTLESC: 292 return (startp); 293 case CTLQUOTEMARK: 294 return (startp); 295 case ':': 296 if (flag & EXP_VARTILDE) 297 goto done; 298 break; 299 case '/': 300 goto done; 301 } 302 p++; 303 } 304 done: 305 *p = '\0'; 306 if (*(startp+1) == '\0') { 307 if ((home = lookupvar("HOME")) == NULL) 308 goto lose; 309 } else { 310 if ((pw = getpwnam(startp+1)) == NULL) 311 goto lose; 312 home = pw->pw_dir; 313 } 314 if (*home == '\0') 315 goto lose; 316 *p = c; 317 while ((c = *home++) != '\0') { 318 if (quotes && SQSYNTAX[c] == CCTL) 319 STPUTC(CTLESC, expdest); 320 STPUTC(c, expdest); 321 } 322 return (p); 323 lose: 324 *p = c; 325 return (startp); 326 } 327 328 329 STATIC void 330 removerecordregions(endoff) 331 int endoff; 332 { 333 if (ifslastp == NULL) 334 return; 335 336 if (ifsfirst.endoff > endoff) { 337 while (ifsfirst.next != NULL) { 338 struct ifsregion *ifsp; 339 INTOFF; 340 ifsp = ifsfirst.next->next; 341 ckfree(ifsfirst.next); 342 ifsfirst.next = ifsp; 343 INTON; 344 } 345 if (ifsfirst.begoff > endoff) 346 ifslastp = NULL; 347 else { 348 ifslastp = &ifsfirst; 349 ifsfirst.endoff = endoff; 350 } 351 return; 352 } 353 354 ifslastp = &ifsfirst; 355 while (ifslastp->next && ifslastp->next->begoff < endoff) 356 ifslastp=ifslastp->next; 357 while (ifslastp->next != NULL) { 358 struct ifsregion *ifsp; 359 INTOFF; 360 ifsp = ifslastp->next->next; 361 ckfree(ifslastp->next); 362 ifslastp->next = ifsp; 363 INTON; 364 } 365 if (ifslastp->endoff > endoff) 366 ifslastp->endoff = endoff; 367 } 368 369 /* 370 * Expand arithmetic expression. Backup to start of expression, 371 * evaluate, place result in (backed up) result, adjust string position. 372 */ 373 void 374 expari(flag) 375 int flag; 376 { 377 char *p, *start; 378 int result; 379 int begoff; 380 int quotes = flag & (EXP_FULL | EXP_CASE); 381 int quoted; 382 383 384 /* 385 * This routine is slightly over-compilcated for 386 * efficiency. First we make sure there is 387 * enough space for the result, which may be bigger 388 * than the expression if we add exponentation. Next we 389 * scan backwards looking for the start of arithmetic. If the 390 * next previous character is a CTLESC character, then we 391 * have to rescan starting from the beginning since CTLESC 392 * characters have to be processed left to right. 393 */ 394 #if INT_MAX / 1000000000 >= 10 || INT_MIN / 1000000000 <= -10 395 #error "integers with more than 10 digits are not supported" 396 #endif 397 CHECKSTRSPACE(12 - 2, expdest); 398 USTPUTC('\0', expdest); 399 start = stackblock(); 400 p = expdest; 401 while (*p != CTLARI && p >= start) 402 --p; 403 if (*p != CTLARI) 404 error("missing CTLARI (shouldn't happen)"); 405 if (p > start && *(p-1) == CTLESC) 406 for (p = start; *p != CTLARI; p++) 407 if (*p == CTLESC) 408 p++; 409 410 if (p[1] == '"') 411 quoted=1; 412 else 413 quoted=0; 414 begoff = p - start; 415 removerecordregions(begoff); 416 if (quotes) 417 rmescapes(p+2); 418 result = arith(p+2); 419 fmtstr(p, 12, "%d", result); 420 while (*p++) 421 ; 422 if (quoted == 0) 423 recordregion(begoff, p - 1 - start, 0); 424 result = expdest - p + 1; 425 STADJUST(-result, expdest); 426 } 427 428 429 /* 430 * Expand stuff in backwards quotes. 431 */ 432 433 STATIC void 434 expbackq(cmd, quoted, flag) 435 union node *cmd; 436 int quoted; 437 int flag; 438 { 439 struct backcmd in; 440 int i; 441 char buf[128]; 442 char *p; 443 char *dest = expdest; 444 struct ifsregion saveifs, *savelastp; 445 struct nodelist *saveargbackq; 446 char lastc; 447 int startloc = dest - stackblock(); 448 char const *syntax = quoted? DQSYNTAX : BASESYNTAX; 449 int saveherefd; 450 int quotes = flag & (EXP_FULL | EXP_CASE); 451 452 INTOFF; 453 saveifs = ifsfirst; 454 savelastp = ifslastp; 455 saveargbackq = argbackq; 456 saveherefd = herefd; 457 herefd = -1; 458 p = grabstackstr(dest); 459 evalbackcmd(cmd, &in); 460 ungrabstackstr(p, dest); 461 ifsfirst = saveifs; 462 ifslastp = savelastp; 463 argbackq = saveargbackq; 464 herefd = saveherefd; 465 466 p = in.buf; 467 lastc = '\0'; 468 for (;;) { 469 if (--in.nleft < 0) { 470 if (in.fd < 0) 471 break; 472 while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR); 473 TRACE(("expbackq: read returns %d\n", i)); 474 if (i <= 0) 475 break; 476 p = buf; 477 in.nleft = i - 1; 478 } 479 lastc = *p++; 480 if (lastc != '\0') { 481 if (quotes && syntax[lastc] == CCTL) 482 STPUTC(CTLESC, dest); 483 STPUTC(lastc, dest); 484 } 485 } 486 487 /* Eat all trailing newlines */ 488 for (p--; lastc == '\n'; lastc = *--p) 489 STUNPUTC(dest); 490 491 if (in.fd >= 0) 492 close(in.fd); 493 if (in.buf) 494 ckfree(in.buf); 495 if (in.jp) 496 exitstatus = waitforjob(in.jp); 497 if (quoted == 0) 498 recordregion(startloc, dest - stackblock(), 0); 499 TRACE(("evalbackq: size=%d: \"%.*s\"\n", 500 (dest - stackblock()) - startloc, 501 (dest - stackblock()) - startloc, 502 stackblock() + startloc)); 503 expdest = dest; 504 INTON; 505 } 506 507 508 509 STATIC int 510 subevalvar(p, str, strloc, subtype, startloc, varflags) 511 char *p; 512 char *str; 513 int strloc; 514 int subtype; 515 int startloc; 516 int varflags; 517 { 518 char *startp; 519 char *loc = NULL; 520 int c = 0; 521 int saveherefd = herefd; 522 struct nodelist *saveargbackq = argbackq; 523 int amount; 524 525 herefd = -1; 526 argstr(p, 0); 527 STACKSTRNUL(expdest); 528 herefd = saveherefd; 529 argbackq = saveargbackq; 530 startp = stackblock() + startloc; 531 if (str == NULL) 532 str = stackblock() + strloc; 533 534 switch (subtype) { 535 case VSASSIGN: 536 setvar(str, startp, 0); 537 amount = startp - expdest; 538 STADJUST(amount, expdest); 539 varflags &= ~VSNUL; 540 if (c != 0) 541 *loc = c; 542 return 1; 543 544 case VSQUESTION: 545 if (*p != CTLENDVAR) { 546 outfmt(&errout, "%s\n", startp); 547 error((char *)NULL); 548 } 549 error("%.*s: parameter %snot set", p - str - 1, 550 str, (varflags & VSNUL) ? "null or " 551 : nullstr); 552 return 0; 553 554 case VSTRIMLEFT: 555 for (loc = startp; loc < str; loc++) { 556 c = *loc; 557 *loc = '\0'; 558 if (patmatch(str, startp)) { 559 *loc = c; 560 goto recordleft; 561 } 562 *loc = c; 563 } 564 return 0; 565 566 case VSTRIMLEFTMAX: 567 for (loc = str - 1; loc >= startp; loc--) { 568 c = *loc; 569 *loc = '\0'; 570 if (patmatch(str, startp)) { 571 *loc = c; 572 goto recordleft; 573 } 574 *loc = c; 575 } 576 return 0; 577 578 case VSTRIMRIGHT: 579 for (loc = str - 1; loc >= startp; loc--) { 580 if (patmatch(str, loc)) { 581 amount = loc - expdest; 582 STADJUST(amount, expdest); 583 return 1; 584 } 585 } 586 return 0; 587 588 case VSTRIMRIGHTMAX: 589 for (loc = startp; loc < str - 1; loc++) { 590 if (patmatch(str, loc)) { 591 amount = loc - expdest; 592 STADJUST(amount, expdest); 593 return 1; 594 } 595 } 596 return 0; 597 598 599 default: 600 abort(); 601 } 602 603 recordleft: 604 amount = ((str - 1) - (loc - startp)) - expdest; 605 STADJUST(amount, expdest); 606 while (loc != str - 1) 607 *startp++ = *loc++; 608 return 1; 609 } 610 611 612 /* 613 * Expand a variable, and return a pointer to the next character in the 614 * input string. 615 */ 616 617 STATIC char * 618 evalvar(p, flag) 619 char *p; 620 int flag; 621 { 622 int subtype; 623 int varflags; 624 char *var; 625 char *val; 626 char *pat; 627 int c; 628 int set; 629 int special; 630 int startloc; 631 int varlen; 632 int easy; 633 int quotes = flag & (EXP_FULL | EXP_CASE); 634 635 varflags = *p++; 636 subtype = varflags & VSTYPE; 637 var = p; 638 special = 0; 639 if (! is_name(*p)) 640 special = 1; 641 p = strchr(p, '=') + 1; 642 again: /* jump here after setting a variable with ${var=text} */ 643 if (special) { 644 set = varisset(var, varflags & VSNUL); 645 val = NULL; 646 } else { 647 val = lookupvar(var); 648 if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) { 649 val = NULL; 650 set = 0; 651 } else 652 set = 1; 653 } 654 varlen = 0; 655 startloc = expdest - stackblock(); 656 if (set && subtype != VSPLUS) { 657 /* insert the value of the variable */ 658 if (special) { 659 varvalue(var, varflags & VSQUOTE, flag & EXP_FULL); 660 if (subtype == VSLENGTH) { 661 varlen = expdest - stackblock() - startloc; 662 STADJUST(-varlen, expdest); 663 } 664 } else { 665 char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX 666 : BASESYNTAX; 667 668 if (subtype == VSLENGTH) { 669 for (;*val; val++) 670 varlen++; 671 } 672 else { 673 while (*val) { 674 if (quotes && syntax[*val] == CCTL) 675 STPUTC(CTLESC, expdest); 676 STPUTC(*val++, expdest); 677 } 678 679 } 680 } 681 } 682 683 if (subtype == VSPLUS) 684 set = ! set; 685 686 easy = ((varflags & VSQUOTE) == 0 || 687 (*var == '@' && shellparam.nparam != 1)); 688 689 690 switch (subtype) { 691 case VSLENGTH: 692 expdest = cvtnum(varlen, expdest); 693 goto record; 694 695 case VSNORMAL: 696 if (!easy) 697 break; 698 record: 699 recordregion(startloc, expdest - stackblock(), 700 varflags & VSQUOTE); 701 break; 702 703 case VSPLUS: 704 case VSMINUS: 705 if (!set) { 706 argstr(p, flag); 707 break; 708 } 709 if (easy) 710 goto record; 711 break; 712 713 case VSTRIMLEFT: 714 case VSTRIMLEFTMAX: 715 case VSTRIMRIGHT: 716 case VSTRIMRIGHTMAX: 717 if (!set) 718 break; 719 /* 720 * Terminate the string and start recording the pattern 721 * right after it 722 */ 723 STPUTC('\0', expdest); 724 pat = expdest; 725 if (subevalvar(p, NULL, expdest - stackblock(), subtype, 726 startloc, varflags) == 0) { 727 int amount = (expdest - pat) + 1; 728 STADJUST(-amount, expdest); 729 } 730 /* Remove any recorded regions beyond start of variable */ 731 removerecordregions(startloc); 732 goto record; 733 734 case VSASSIGN: 735 case VSQUESTION: 736 if (!set) { 737 if (subevalvar(p, var, 0, subtype, startloc, varflags)) { 738 varflags &= ~VSNUL; 739 /* 740 * Remove any recorded regions beyond 741 * start of variable 742 */ 743 removerecordregions(startloc); 744 goto again; 745 } 746 break; 747 } 748 if (easy) 749 goto record; 750 break; 751 752 default: 753 abort(); 754 } 755 756 if (subtype != VSNORMAL) { /* skip to end of alternative */ 757 int nesting = 1; 758 for (;;) { 759 if ((c = *p++) == CTLESC) 760 p++; 761 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { 762 if (set) 763 argbackq = argbackq->next; 764 } else if (c == CTLVAR) { 765 if ((*p++ & VSTYPE) != VSNORMAL) 766 nesting++; 767 } else if (c == CTLENDVAR) { 768 if (--nesting == 0) 769 break; 770 } 771 } 772 } 773 return p; 774 } 775 776 777 778 /* 779 * Test whether a specialized variable is set. 780 */ 781 782 STATIC int 783 varisset(name, nulok) 784 char *name; 785 int nulok; 786 { 787 788 if (*name == '!') 789 return backgndpid != -1; 790 else if (*name == '@' || *name == '*') { 791 if (*shellparam.p == NULL) 792 return 0; 793 794 if (nulok) { 795 char **av; 796 797 for (av = shellparam.p; *av; av++) 798 if (**av != '\0') 799 return 1; 800 return 0; 801 } 802 } else if (is_digit(*name)) { 803 char *ap; 804 int num = atoi(name); 805 806 if (num > shellparam.nparam) 807 return 0; 808 809 if (num == 0) 810 ap = arg0; 811 else 812 ap = shellparam.p[num - 1]; 813 814 if (nulok && (ap == NULL || *ap == '\0')) 815 return 0; 816 } 817 return 1; 818 } 819 820 821 822 /* 823 * Add the value of a specialized variable to the stack string. 824 */ 825 826 STATIC void 827 varvalue(name, quoted, allow_split) 828 char *name; 829 int quoted; 830 int allow_split; 831 { 832 int num; 833 char *p; 834 int i; 835 extern int oexitstatus; 836 char sep; 837 char **ap; 838 char const *syntax; 839 840 #define STRTODEST(p) \ 841 do {\ 842 if (allow_split) { \ 843 syntax = quoted? DQSYNTAX : BASESYNTAX; \ 844 while (*p) { \ 845 if (syntax[*p] == CCTL) \ 846 STPUTC(CTLESC, expdest); \ 847 STPUTC(*p++, expdest); \ 848 } \ 849 } else \ 850 while (*p) \ 851 STPUTC(*p++, expdest); \ 852 } while (0) 853 854 855 switch (*name) { 856 case '$': 857 num = rootpid; 858 goto numvar; 859 case '?': 860 num = oexitstatus; 861 goto numvar; 862 case '#': 863 num = shellparam.nparam; 864 goto numvar; 865 case '!': 866 num = backgndpid; 867 numvar: 868 expdest = cvtnum(num, expdest); 869 break; 870 case '-': 871 for (i = 0 ; i < NOPTS ; i++) { 872 if (optlist[i].val) 873 STPUTC(optlist[i].letter, expdest); 874 } 875 break; 876 case '@': 877 if (allow_split && quoted) { 878 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 879 STRTODEST(p); 880 if (*ap) 881 STPUTC('\0', expdest); 882 } 883 break; 884 } 885 /* fall through */ 886 case '*': 887 if (ifsset() != 0) 888 sep = ifsval()[0]; 889 else 890 sep = ' '; 891 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 892 STRTODEST(p); 893 if (*ap && sep) 894 STPUTC(sep, expdest); 895 } 896 break; 897 case '0': 898 p = arg0; 899 STRTODEST(p); 900 break; 901 default: 902 if (is_digit(*name)) { 903 num = atoi(name); 904 if (num > 0 && num <= shellparam.nparam) { 905 p = shellparam.p[num - 1]; 906 STRTODEST(p); 907 } 908 } 909 break; 910 } 911 } 912 913 914 915 /* 916 * Record the the fact that we have to scan this region of the 917 * string for IFS characters. 918 */ 919 920 STATIC void 921 recordregion(start, end, nulonly) 922 int start; 923 int end; 924 int nulonly; 925 { 926 struct ifsregion *ifsp; 927 928 if (ifslastp == NULL) { 929 ifsp = &ifsfirst; 930 } else { 931 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 932 ifslastp->next = ifsp; 933 } 934 ifslastp = ifsp; 935 ifslastp->next = NULL; 936 ifslastp->begoff = start; 937 ifslastp->endoff = end; 938 ifslastp->nulonly = nulonly; 939 } 940 941 942 943 /* 944 * Break the argument string into pieces based upon IFS and add the 945 * strings to the argument list. The regions of the string to be 946 * searched for IFS characters have been stored by recordregion. 947 */ 948 STATIC void 949 ifsbreakup(string, arglist) 950 char *string; 951 struct arglist *arglist; 952 { 953 struct ifsregion *ifsp; 954 struct strlist *sp; 955 char *start; 956 char *p; 957 char *q; 958 char *ifs; 959 int ifsspc; 960 int nulonly; 961 962 963 start = string; 964 ifsspc = 0; 965 nulonly = 0; 966 if (ifslastp != NULL) { 967 ifsp = &ifsfirst; 968 do { 969 p = string + ifsp->begoff; 970 nulonly = ifsp->nulonly; 971 ifs = nulonly ? nullstr : 972 ( ifsset() ? ifsval() : " \t\n" ); 973 ifsspc = 0; 974 while (p < string + ifsp->endoff) { 975 q = p; 976 if (*p == CTLESC) 977 p++; 978 if (strchr(ifs, *p)) { 979 if (!nulonly) 980 ifsspc = (strchr(" \t\n", *p) != NULL); 981 /* Ignore IFS whitespace at start */ 982 if (q == start && ifsspc) { 983 p++; 984 start = p; 985 continue; 986 } 987 *q = '\0'; 988 sp = (struct strlist *)stalloc(sizeof *sp); 989 sp->text = start; 990 *arglist->lastp = sp; 991 arglist->lastp = &sp->next; 992 p++; 993 if (!nulonly) { 994 for (;;) { 995 if (p >= string + ifsp->endoff) { 996 break; 997 } 998 q = p; 999 if (*p == CTLESC) 1000 p++; 1001 if (strchr(ifs, *p) == NULL ) { 1002 p = q; 1003 break; 1004 } else if (strchr(" \t\n",*p) == NULL) { 1005 if (ifsspc) { 1006 p++; 1007 ifsspc = 0; 1008 } else { 1009 p = q; 1010 break; 1011 } 1012 } else 1013 p++; 1014 } 1015 } 1016 start = p; 1017 } else 1018 p++; 1019 } 1020 } while ((ifsp = ifsp->next) != NULL); 1021 if (*start || (!ifsspc && start > string && 1022 (nulonly || 1))) { 1023 sp = (struct strlist *)stalloc(sizeof *sp); 1024 sp->text = start; 1025 *arglist->lastp = sp; 1026 arglist->lastp = &sp->next; 1027 } 1028 } else { 1029 sp = (struct strlist *)stalloc(sizeof *sp); 1030 sp->text = start; 1031 *arglist->lastp = sp; 1032 arglist->lastp = &sp->next; 1033 } 1034 } 1035 1036 1037 1038 /* 1039 * Expand shell metacharacters. At this point, the only control characters 1040 * should be escapes. The results are stored in the list exparg. 1041 */ 1042 1043 char *expdir; 1044 1045 1046 STATIC void 1047 expandmeta(str, flag) 1048 struct strlist *str; 1049 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(enddir, name) 1104 char *enddir; 1105 char *name; 1106 { 1107 char *p; 1108 char *q; 1109 char *start; 1110 char *endname; 1111 int metaflag; 1112 struct stat statb; 1113 DIR *dirp; 1114 struct dirent *dp; 1115 int atend; 1116 int matchdot; 1117 1118 metaflag = 0; 1119 start = name; 1120 for (p = name ; ; p++) { 1121 if (*p == '*' || *p == '?') 1122 metaflag = 1; 1123 else if (*p == '[') { 1124 q = p + 1; 1125 if (*q == '!' || *q == '^') 1126 q++; 1127 for (;;) { 1128 while (*q == CTLQUOTEMARK) 1129 q++; 1130 if (*q == CTLESC) 1131 q++; 1132 if (*q == '/' || *q == '\0') 1133 break; 1134 if (*++q == ']') { 1135 metaflag = 1; 1136 break; 1137 } 1138 } 1139 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 1140 metaflag = 1; 1141 } else if (*p == '\0') 1142 break; 1143 else if (*p == CTLQUOTEMARK) 1144 continue; 1145 else if (*p == CTLESC) 1146 p++; 1147 if (*p == '/') { 1148 if (metaflag) 1149 break; 1150 start = p + 1; 1151 } 1152 } 1153 if (metaflag == 0) { /* we've reached the end of the file name */ 1154 if (enddir != expdir) 1155 metaflag++; 1156 for (p = name ; ; p++) { 1157 if (*p == CTLQUOTEMARK) 1158 continue; 1159 if (*p == CTLESC) 1160 p++; 1161 *enddir++ = *p; 1162 if (*p == '\0') 1163 break; 1164 } 1165 if (metaflag == 0 || stat(expdir, &statb) >= 0) 1166 addfname(expdir); 1167 return; 1168 } 1169 endname = p; 1170 if (start != name) { 1171 p = name; 1172 while (p < start) { 1173 while (*p == CTLQUOTEMARK) 1174 p++; 1175 if (*p == CTLESC) 1176 p++; 1177 *enddir++ = *p++; 1178 } 1179 } 1180 if (enddir == expdir) { 1181 p = "."; 1182 } else if (enddir == expdir + 1 && *expdir == '/') { 1183 p = "/"; 1184 } else { 1185 p = expdir; 1186 enddir[-1] = '\0'; 1187 } 1188 if ((dirp = opendir(p)) == NULL) 1189 return; 1190 if (enddir != expdir) 1191 enddir[-1] = '/'; 1192 if (*endname == 0) { 1193 atend = 1; 1194 } else { 1195 atend = 0; 1196 *endname++ = '\0'; 1197 } 1198 matchdot = 0; 1199 p = start; 1200 while (*p == CTLQUOTEMARK) 1201 p++; 1202 if (*p == CTLESC) 1203 p++; 1204 if (*p == '.') 1205 matchdot++; 1206 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 1207 if (dp->d_name[0] == '.' && ! matchdot) 1208 continue; 1209 if (patmatch(start, dp->d_name)) { 1210 if (atend) { 1211 scopy(dp->d_name, enddir); 1212 addfname(expdir); 1213 } else { 1214 char *q; 1215 for (p = enddir, q = dp->d_name; 1216 (*p++ = *q++) != '\0';) 1217 continue; 1218 p[-1] = '/'; 1219 expmeta(p, endname); 1220 } 1221 } 1222 } 1223 closedir(dirp); 1224 if (! atend) 1225 endname[-1] = '/'; 1226 } 1227 1228 1229 /* 1230 * Add a file name to the list. 1231 */ 1232 1233 STATIC void 1234 addfname(name) 1235 char *name; 1236 { 1237 char *p; 1238 struct strlist *sp; 1239 1240 p = stalloc(strlen(name) + 1); 1241 scopy(name, p); 1242 sp = (struct strlist *)stalloc(sizeof *sp); 1243 sp->text = p; 1244 *exparg.lastp = sp; 1245 exparg.lastp = &sp->next; 1246 } 1247 1248 1249 /* 1250 * Sort the results of file name expansion. It calculates the number of 1251 * strings to sort and then calls msort (short for merge sort) to do the 1252 * work. 1253 */ 1254 1255 STATIC struct strlist * 1256 expsort(str) 1257 struct strlist *str; 1258 { 1259 int len; 1260 struct strlist *sp; 1261 1262 len = 0; 1263 for (sp = str ; sp ; sp = sp->next) 1264 len++; 1265 return msort(str, len); 1266 } 1267 1268 1269 STATIC struct strlist * 1270 msort(list, len) 1271 struct strlist *list; 1272 int len; 1273 { 1274 struct strlist *p, *q = NULL; 1275 struct strlist **lpp; 1276 int half; 1277 int n; 1278 1279 if (len <= 1) 1280 return list; 1281 half = len >> 1; 1282 p = list; 1283 for (n = half ; --n >= 0 ; ) { 1284 q = p; 1285 p = p->next; 1286 } 1287 q->next = NULL; /* terminate first half of list */ 1288 q = msort(list, half); /* sort first half of list */ 1289 p = msort(p, len - half); /* sort second half */ 1290 lpp = &list; 1291 for (;;) { 1292 if (strcmp(p->text, q->text) < 0) { 1293 *lpp = p; 1294 lpp = &p->next; 1295 if ((p = *lpp) == NULL) { 1296 *lpp = q; 1297 break; 1298 } 1299 } else { 1300 *lpp = q; 1301 lpp = &q->next; 1302 if ((q = *lpp) == NULL) { 1303 *lpp = p; 1304 break; 1305 } 1306 } 1307 } 1308 return list; 1309 } 1310 1311 1312 1313 /* 1314 * Returns true if the pattern matches the string. 1315 */ 1316 1317 int 1318 patmatch(pattern, string) 1319 char *pattern; 1320 char *string; 1321 { 1322 #ifdef notdef 1323 if (pattern[0] == '!' && pattern[1] == '!') 1324 return 1 - pmatch(pattern + 2, string); 1325 else 1326 #endif 1327 return pmatch(pattern, string); 1328 } 1329 1330 1331 STATIC int 1332 pmatch(pattern, string) 1333 char *pattern; 1334 char *string; 1335 { 1336 char *p, *q; 1337 char c; 1338 1339 p = pattern; 1340 q = string; 1341 for (;;) { 1342 switch (c = *p++) { 1343 case '\0': 1344 goto breakloop; 1345 case CTLESC: 1346 if (*q++ != *p++) 1347 return 0; 1348 break; 1349 case CTLQUOTEMARK: 1350 continue; 1351 case '?': 1352 if (*q++ == '\0') 1353 return 0; 1354 break; 1355 case '*': 1356 c = *p; 1357 while (c == CTLQUOTEMARK || c == '*') 1358 c = *++p; 1359 if (c != CTLESC && c != CTLQUOTEMARK && 1360 c != '?' && c != '*' && c != '[') { 1361 while (*q != c) { 1362 if (*q == '\0') 1363 return 0; 1364 q++; 1365 } 1366 } 1367 do { 1368 if (pmatch(p, q)) 1369 return 1; 1370 } while (*q++ != '\0'); 1371 return 0; 1372 case '[': { 1373 char *endp; 1374 int invert, found; 1375 char chr; 1376 1377 endp = p; 1378 if (*endp == '!' || *endp == '^') 1379 endp++; 1380 for (;;) { 1381 while (*endp == CTLQUOTEMARK) 1382 endp++; 1383 if (*endp == '\0') 1384 goto dft; /* no matching ] */ 1385 if (*endp == CTLESC) 1386 endp++; 1387 if (*++endp == ']') 1388 break; 1389 } 1390 invert = 0; 1391 if (*p == '!' || *p == '^') { 1392 invert++; 1393 p++; 1394 } 1395 found = 0; 1396 chr = *q++; 1397 if (chr == '\0') 1398 return 0; 1399 c = *p++; 1400 do { 1401 if (c == CTLQUOTEMARK) 1402 continue; 1403 if (c == CTLESC) 1404 c = *p++; 1405 if (*p == '-' && p[1] != ']') { 1406 p++; 1407 while (*p == CTLQUOTEMARK) 1408 p++; 1409 if (*p == CTLESC) 1410 p++; 1411 if ( collate_range_cmp(chr, c) >= 0 1412 && collate_range_cmp(chr, *p) <= 0 1413 ) 1414 found = 1; 1415 p++; 1416 } else { 1417 if (chr == c) 1418 found = 1; 1419 } 1420 } while ((c = *p++) != ']'); 1421 if (found == invert) 1422 return 0; 1423 break; 1424 } 1425 dft: default: 1426 if (*q++ != c) 1427 return 0; 1428 break; 1429 } 1430 } 1431 breakloop: 1432 if (*q != '\0') 1433 return 0; 1434 return 1; 1435 } 1436 1437 1438 1439 /* 1440 * Remove any CTLESC characters from a string. 1441 */ 1442 1443 void 1444 rmescapes(str) 1445 char *str; 1446 { 1447 char *p, *q; 1448 1449 p = str; 1450 while (*p != CTLESC && *p != CTLQUOTEMARK) { 1451 if (*p++ == '\0') 1452 return; 1453 } 1454 q = p; 1455 while (*p) { 1456 if (*p == CTLQUOTEMARK) { 1457 p++; 1458 continue; 1459 } 1460 if (*p == CTLESC) 1461 p++; 1462 *q++ = *p++; 1463 } 1464 *q = '\0'; 1465 } 1466 1467 1468 1469 /* 1470 * See if a pattern matches in a case statement. 1471 */ 1472 1473 int 1474 casematch(pattern, val) 1475 union node *pattern; 1476 char *val; 1477 { 1478 struct stackmark smark; 1479 int result; 1480 char *p; 1481 1482 setstackmark(&smark); 1483 argbackq = pattern->narg.backquote; 1484 STARTSTACKSTR(expdest); 1485 ifslastp = NULL; 1486 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); 1487 STPUTC('\0', expdest); 1488 p = grabstackstr(expdest); 1489 result = patmatch(p, val); 1490 popstackmark(&smark); 1491 return result; 1492 } 1493 1494 /* 1495 * Our own itoa(). 1496 */ 1497 1498 STATIC char * 1499 cvtnum(num, buf) 1500 int num; 1501 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