1 /* $NetBSD: expand.c,v 1.44 1999/02/06 17:23:09 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Kenneth Almquist. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 #ifndef lint 41 #if 0 42 static char sccsid[] = "@(#)expand.c 8.5 (Berkeley) 5/15/95"; 43 #else 44 __RCSID("$NetBSD: expand.c,v 1.44 1999/02/06 17:23:09 christos Exp $"); 45 #endif 46 #endif /* not lint */ 47 48 #include <sys/types.h> 49 #include <sys/time.h> 50 #include <sys/stat.h> 51 #include <errno.h> 52 #include <dirent.h> 53 #include <unistd.h> 54 #include <pwd.h> 55 #include <stdlib.h> 56 #include <stdio.h> 57 58 /* 59 * Routines to expand arguments to commands. We have to deal with 60 * backquotes, shell variables, and file metacharacters. 61 */ 62 63 #include "shell.h" 64 #include "main.h" 65 #include "nodes.h" 66 #include "eval.h" 67 #include "expand.h" 68 #include "syntax.h" 69 #include "parser.h" 70 #include "jobs.h" 71 #include "options.h" 72 #include "var.h" 73 #include "input.h" 74 #include "output.h" 75 #include "memalloc.h" 76 #include "error.h" 77 #include "mystring.h" 78 #include "show.h" 79 80 /* 81 * Structure specifying which parts of the string should be searched 82 * for IFS characters. 83 */ 84 85 struct ifsregion { 86 struct ifsregion *next; /* next region in list */ 87 int begoff; /* offset of start of region */ 88 int endoff; /* offset of end of region */ 89 int nulonly; /* search for nul bytes only */ 90 }; 91 92 93 char *expdest; /* output of current string */ 94 struct nodelist *argbackq; /* list of back quote expressions */ 95 struct ifsregion ifsfirst; /* first struct in list of ifs regions */ 96 struct ifsregion *ifslastp; /* last struct in list */ 97 struct arglist exparg; /* holds expanded arg list */ 98 99 STATIC void argstr __P((char *, int)); 100 STATIC char *exptilde __P((char *, int)); 101 STATIC void expbackq __P((union node *, int, int)); 102 STATIC int subevalvar __P((char *, char *, int, int, int, int)); 103 STATIC char *evalvar __P((char *, int)); 104 STATIC int varisset __P((char *, int)); 105 STATIC void varvalue __P((char *, int, int)); 106 STATIC void recordregion __P((int, int, int)); 107 STATIC void removerecordregions __P((int)); 108 STATIC void ifsbreakup __P((char *, struct arglist *)); 109 STATIC void ifsfree __P((void)); 110 STATIC void expandmeta __P((struct strlist *, int)); 111 STATIC void expmeta __P((char *, char *)); 112 STATIC void addfname __P((char *)); 113 STATIC struct strlist *expsort __P((struct strlist *)); 114 STATIC struct strlist *msort __P((struct strlist *, int)); 115 STATIC int pmatch __P((char *, char *)); 116 STATIC char *cvtnum __P((int, char *)); 117 118 /* 119 * Expand shell variables and backquotes inside a here document. 120 */ 121 122 void 123 expandhere(arg, fd) 124 union node *arg; /* the document */ 125 int fd; /* where to write the expanded version */ 126 { 127 herefd = fd; 128 expandarg(arg, (struct arglist *)NULL, 0); 129 xwrite(fd, stackblock(), expdest - stackblock()); 130 } 131 132 133 /* 134 * Perform variable substitution and command substitution on an argument, 135 * placing the resulting list of arguments in arglist. If EXP_FULL is true, 136 * perform splitting and file name expansion. When arglist is NULL, perform 137 * here document expansion. 138 */ 139 140 void 141 expandarg(arg, arglist, flag) 142 union node *arg; 143 struct arglist *arglist; 144 int flag; 145 { 146 struct strlist *sp; 147 char *p; 148 149 argbackq = arg->narg.backquote; 150 STARTSTACKSTR(expdest); 151 ifsfirst.next = NULL; 152 ifslastp = NULL; 153 argstr(arg->narg.text, flag); 154 if (arglist == NULL) { 155 return; /* here document expanded */ 156 } 157 STPUTC('\0', expdest); 158 p = grabstackstr(expdest); 159 exparg.lastp = &exparg.list; 160 /* 161 * TODO - EXP_REDIR 162 */ 163 if (flag & EXP_FULL) { 164 ifsbreakup(p, &exparg); 165 *exparg.lastp = NULL; 166 exparg.lastp = &exparg.list; 167 expandmeta(exparg.list, flag); 168 } else { 169 if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */ 170 rmescapes(p); 171 sp = (struct strlist *)stalloc(sizeof (struct strlist)); 172 sp->text = p; 173 *exparg.lastp = sp; 174 exparg.lastp = &sp->next; 175 } 176 ifsfree(); 177 *exparg.lastp = NULL; 178 if (exparg.list) { 179 *arglist->lastp = exparg.list; 180 arglist->lastp = exparg.lastp; 181 } 182 } 183 184 185 186 /* 187 * Perform variable and command substitution. If EXP_FULL is set, output CTLESC 188 * characters to allow for further processing. Otherwise treat 189 * $@ like $* since no splitting will be performed. 190 */ 191 192 STATIC void 193 argstr(p, flag) 194 char *p; 195 int flag; 196 { 197 char c; 198 int quotes = flag & (EXP_FULL | EXP_CASE); /* do CTLESC */ 199 int firsteq = 1; 200 201 if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE))) 202 p = exptilde(p, flag); 203 for (;;) { 204 switch (c = *p++) { 205 case '\0': 206 case CTLENDVAR: /* ??? */ 207 goto breakloop; 208 case CTLQUOTEMARK: 209 /* "$@" syntax adherence hack */ 210 if (p[0] == CTLVAR && p[2] == '@' && p[3] == '=') 211 break; 212 if ((flag & EXP_FULL) != 0) 213 STPUTC(c, expdest); 214 break; 215 case CTLESC: 216 if (quotes) 217 STPUTC(c, expdest); 218 c = *p++; 219 STPUTC(c, expdest); 220 break; 221 case CTLVAR: 222 p = evalvar(p, flag); 223 break; 224 case CTLBACKQ: 225 case CTLBACKQ|CTLQUOTE: 226 expbackq(argbackq->n, c & CTLQUOTE, flag); 227 argbackq = argbackq->next; 228 break; 229 case CTLENDARI: 230 expari(flag); 231 break; 232 case ':': 233 case '=': 234 /* 235 * sort of a hack - expand tildes in variable 236 * assignments (after the first '=' and after ':'s). 237 */ 238 STPUTC(c, expdest); 239 if (flag & EXP_VARTILDE && *p == '~') { 240 if (c == '=') { 241 if (firsteq) 242 firsteq = 0; 243 else 244 break; 245 } 246 p = exptilde(p, flag); 247 } 248 break; 249 default: 250 STPUTC(c, expdest); 251 } 252 } 253 breakloop:; 254 return; 255 } 256 257 STATIC char * 258 exptilde(p, flag) 259 char *p; 260 int flag; 261 { 262 char c, *startp = p; 263 struct passwd *pw; 264 const char *home; 265 int quotes = flag & (EXP_FULL | EXP_CASE); 266 267 while ((c = *p) != '\0') { 268 switch(c) { 269 case CTLESC: 270 return (startp); 271 case CTLQUOTEMARK: 272 return (startp); 273 case ':': 274 if (flag & EXP_VARTILDE) 275 goto done; 276 break; 277 case '/': 278 goto done; 279 } 280 p++; 281 } 282 done: 283 *p = '\0'; 284 if (*(startp+1) == '\0') { 285 if ((home = lookupvar("HOME")) == NULL) 286 goto lose; 287 } else { 288 if ((pw = getpwnam(startp+1)) == NULL) 289 goto lose; 290 home = pw->pw_dir; 291 } 292 if (*home == '\0') 293 goto lose; 294 *p = c; 295 while ((c = *home++) != '\0') { 296 if (quotes && SQSYNTAX[(int)c] == CCTL) 297 STPUTC(CTLESC, expdest); 298 STPUTC(c, expdest); 299 } 300 return (p); 301 lose: 302 *p = c; 303 return (startp); 304 } 305 306 307 STATIC void 308 removerecordregions(endoff) 309 int endoff; 310 { 311 if (ifslastp == NULL) 312 return; 313 314 if (ifsfirst.endoff > endoff) { 315 while (ifsfirst.next != NULL) { 316 struct ifsregion *ifsp; 317 INTOFF; 318 ifsp = ifsfirst.next->next; 319 ckfree(ifsfirst.next); 320 ifsfirst.next = ifsp; 321 INTON; 322 } 323 if (ifsfirst.begoff > endoff) 324 ifslastp = NULL; 325 else { 326 ifslastp = &ifsfirst; 327 ifsfirst.endoff = endoff; 328 } 329 return; 330 } 331 332 ifslastp = &ifsfirst; 333 while (ifslastp->next && ifslastp->next->begoff < endoff) 334 ifslastp=ifslastp->next; 335 while (ifslastp->next != NULL) { 336 struct ifsregion *ifsp; 337 INTOFF; 338 ifsp = ifslastp->next->next; 339 ckfree(ifslastp->next); 340 ifslastp->next = ifsp; 341 INTON; 342 } 343 if (ifslastp->endoff > endoff) 344 ifslastp->endoff = endoff; 345 } 346 347 348 /* 349 * Expand arithmetic expression. Backup to start of expression, 350 * evaluate, place result in (backed up) result, adjust string position. 351 */ 352 void 353 expari(flag) 354 int flag; 355 { 356 char *p, *start; 357 int result; 358 int begoff; 359 int quotes = flag & (EXP_FULL | EXP_CASE); 360 int quoted; 361 362 /* ifsfree(); */ 363 364 /* 365 * This routine is slightly over-complicated for 366 * efficiency. First we make sure there is 367 * enough space for the result, which may be bigger 368 * than the expression if we add exponentation. Next we 369 * scan backwards looking for the start of arithmetic. If the 370 * next previous character is a CTLESC character, then we 371 * have to rescan starting from the beginning since CTLESC 372 * characters have to be processed left to right. 373 */ 374 CHECKSTRSPACE(8, expdest); 375 USTPUTC('\0', expdest); 376 start = stackblock(); 377 p = expdest - 1; 378 while (*p != CTLARI && p >= start) 379 --p; 380 if (*p != CTLARI) 381 error("missing CTLARI (shouldn't happen)"); 382 if (p > start && *(p-1) == CTLESC) 383 for (p = start; *p != CTLARI; p++) 384 if (*p == CTLESC) 385 p++; 386 387 if (p[1] == '"') 388 quoted=1; 389 else 390 quoted=0; 391 begoff = p - start; 392 removerecordregions(begoff); 393 if (quotes) 394 rmescapes(p+2); 395 result = arith(p+2); 396 fmtstr(p, 10, "%d", result); 397 398 while (*p++) 399 ; 400 401 if (quoted == 0) 402 recordregion(begoff, p - 1 - start, 0); 403 result = expdest - p + 1; 404 STADJUST(-result, expdest); 405 } 406 407 408 /* 409 * Expand stuff in backwards quotes. 410 */ 411 412 STATIC void 413 expbackq(cmd, quoted, flag) 414 union node *cmd; 415 int quoted; 416 int flag; 417 { 418 struct backcmd in; 419 int i; 420 char buf[128]; 421 char *p; 422 char *dest = expdest; 423 struct ifsregion saveifs, *savelastp; 424 struct nodelist *saveargbackq; 425 char lastc; 426 int startloc = dest - stackblock(); 427 char const *syntax = quoted? DQSYNTAX : BASESYNTAX; 428 int saveherefd; 429 int quotes = flag & (EXP_FULL | EXP_CASE); 430 431 INTOFF; 432 saveifs = ifsfirst; 433 savelastp = ifslastp; 434 saveargbackq = argbackq; 435 saveherefd = herefd; 436 herefd = -1; 437 p = grabstackstr(dest); 438 evalbackcmd(cmd, &in); 439 ungrabstackstr(p, dest); 440 ifsfirst = saveifs; 441 ifslastp = savelastp; 442 argbackq = saveargbackq; 443 herefd = saveherefd; 444 445 p = in.buf; 446 lastc = '\0'; 447 for (;;) { 448 if (--in.nleft < 0) { 449 if (in.fd < 0) 450 break; 451 while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR); 452 TRACE(("expbackq: read returns %d\n", i)); 453 if (i <= 0) 454 break; 455 p = buf; 456 in.nleft = i - 1; 457 } 458 lastc = *p++; 459 if (lastc != '\0') { 460 if (quotes && syntax[(int)lastc] == CCTL) 461 STPUTC(CTLESC, dest); 462 STPUTC(lastc, dest); 463 } 464 } 465 466 /* Eat all trailing newlines */ 467 for (p--; lastc == '\n'; lastc = *--p) 468 STUNPUTC(dest); 469 470 if (in.fd >= 0) 471 close(in.fd); 472 if (in.buf) 473 ckfree(in.buf); 474 if (in.jp) 475 exitstatus = waitforjob(in.jp); 476 if (quoted == 0) 477 recordregion(startloc, dest - stackblock(), 0); 478 TRACE(("evalbackq: size=%d: \"%.*s\"\n", 479 (dest - stackblock()) - startloc, 480 (dest - stackblock()) - startloc, 481 stackblock() + startloc)); 482 expdest = dest; 483 INTON; 484 } 485 486 487 488 STATIC int 489 subevalvar(p, str, strloc, subtype, startloc, varflags) 490 char *p; 491 char *str; 492 int strloc; 493 int subtype; 494 int startloc; 495 int varflags; 496 { 497 char *startp; 498 char *loc = NULL; 499 int c = 0; 500 int saveherefd = herefd; 501 struct nodelist *saveargbackq = argbackq; 502 int amount; 503 504 herefd = -1; 505 argstr(p, 0); 506 STACKSTRNUL(expdest); 507 herefd = saveherefd; 508 argbackq = saveargbackq; 509 startp = stackblock() + startloc; 510 if (str == NULL) 511 str = stackblock() + strloc; 512 513 switch (subtype) { 514 case VSASSIGN: 515 setvar(str, startp, 0); 516 amount = startp - expdest; 517 STADJUST(amount, expdest); 518 varflags &= ~VSNUL; 519 if (c != 0) 520 *loc = c; 521 return 1; 522 523 case VSQUESTION: 524 if (*p != CTLENDVAR) { 525 outfmt(&errout, "%s\n", startp); 526 error((char *)NULL); 527 } 528 error("%.*s: parameter %snot set", p - str - 1, 529 str, (varflags & VSNUL) ? "null or " 530 : nullstr); 531 /* NOTREACHED */ 532 533 case VSTRIMLEFT: 534 for (loc = startp; loc < str; loc++) { 535 c = *loc; 536 *loc = '\0'; 537 if (patmatch(str, startp)) 538 goto recordleft; 539 *loc = c; 540 } 541 return 0; 542 543 case VSTRIMLEFTMAX: 544 for (loc = str - 1; loc >= startp; loc--) { 545 c = *loc; 546 *loc = '\0'; 547 if (patmatch(str, startp)) 548 goto recordleft; 549 *loc = c; 550 } 551 return 0; 552 553 case VSTRIMRIGHT: 554 for (loc = str - 1; loc >= startp; loc--) 555 if (patmatch(str, loc)) 556 goto recordright; 557 return 0; 558 559 case VSTRIMRIGHTMAX: 560 for (loc = startp; loc < str - 1; loc++) 561 if (patmatch(str, loc)) 562 goto recordright; 563 return 0; 564 565 default: 566 abort(); 567 } 568 569 recordleft: 570 *loc = c; 571 amount = ((str - 1) - (loc - startp)) - expdest; 572 STADJUST(amount, expdest); 573 while (loc != str - 1) 574 *startp++ = *loc++; 575 return 1; 576 577 recordright: 578 amount = loc - expdest; 579 STADJUST(amount, expdest); 580 STPUTC('\0', expdest); 581 STADJUST(-1, expdest); 582 return 1; 583 } 584 585 586 /* 587 * Expand a variable, and return a pointer to the next character in the 588 * input string. 589 */ 590 591 STATIC char * 592 evalvar(p, flag) 593 char *p; 594 int flag; 595 { 596 int subtype; 597 int varflags; 598 char *var; 599 char *val; 600 char *pat; 601 int c; 602 int set; 603 int special; 604 int startloc; 605 int varlen; 606 int easy; 607 int quotes = flag & (EXP_FULL | EXP_CASE); 608 609 varflags = *p++; 610 subtype = varflags & VSTYPE; 611 var = p; 612 special = 0; 613 if (! is_name(*p)) 614 special = 1; 615 p = strchr(p, '=') + 1; 616 again: /* jump here after setting a variable with ${var=text} */ 617 if (special) { 618 set = varisset(var, varflags & VSNUL); 619 val = NULL; 620 } else { 621 val = lookupvar(var); 622 if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) { 623 val = NULL; 624 set = 0; 625 } else 626 set = 1; 627 } 628 varlen = 0; 629 startloc = expdest - stackblock(); 630 if (set && subtype != VSPLUS) { 631 /* insert the value of the variable */ 632 if (special) { 633 varvalue(var, varflags & VSQUOTE, flag & EXP_FULL); 634 if (subtype == VSLENGTH) { 635 varlen = expdest - stackblock() - startloc; 636 STADJUST(-varlen, expdest); 637 } 638 } else { 639 char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX 640 : BASESYNTAX; 641 642 if (subtype == VSLENGTH) { 643 for (;*val; val++) 644 varlen++; 645 } 646 else { 647 while (*val) { 648 if (quotes && syntax[(int)*val] == CCTL) 649 STPUTC(CTLESC, expdest); 650 STPUTC(*val++, expdest); 651 } 652 653 } 654 } 655 } 656 657 if (subtype == VSPLUS) 658 set = ! set; 659 660 easy = ((varflags & VSQUOTE) == 0 || 661 (*var == '@' && shellparam.nparam != 1)); 662 663 664 switch (subtype) { 665 case VSLENGTH: 666 expdest = cvtnum(varlen, expdest); 667 goto record; 668 669 case VSNORMAL: 670 if (!easy) 671 break; 672 record: 673 recordregion(startloc, expdest - stackblock(), 674 varflags & VSQUOTE); 675 break; 676 677 case VSPLUS: 678 case VSMINUS: 679 if (!set) { 680 argstr(p, flag); 681 break; 682 } 683 if (easy) 684 goto record; 685 break; 686 687 case VSTRIMLEFT: 688 case VSTRIMLEFTMAX: 689 case VSTRIMRIGHT: 690 case VSTRIMRIGHTMAX: 691 if (!set) 692 break; 693 /* 694 * Terminate the string and start recording the pattern 695 * right after it 696 */ 697 STPUTC('\0', expdest); 698 pat = expdest; 699 if (subevalvar(p, NULL, expdest - stackblock(), subtype, 700 startloc, varflags) == 0) { 701 int amount = (expdest - pat) + 1; 702 STADJUST(-amount, expdest); 703 } 704 /* Remove any recorded regions beyond start of variable */ 705 removerecordregions(startloc); 706 goto record; 707 708 case VSASSIGN: 709 case VSQUESTION: 710 if (!set) { 711 if (subevalvar(p, var, 0, subtype, startloc, 712 varflags)) { 713 varflags &= ~VSNUL; 714 /* 715 * Remove any recorded regions beyond 716 * start of variable 717 */ 718 removerecordregions(startloc); 719 goto again; 720 } 721 break; 722 } 723 if (easy) 724 goto record; 725 break; 726 727 default: 728 abort(); 729 } 730 731 if (subtype != VSNORMAL) { /* skip to end of alternative */ 732 int nesting = 1; 733 for (;;) { 734 if ((c = *p++) == CTLESC) 735 p++; 736 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { 737 if (set) 738 argbackq = argbackq->next; 739 } else if (c == CTLVAR) { 740 if ((*p++ & VSTYPE) != VSNORMAL) 741 nesting++; 742 } else if (c == CTLENDVAR) { 743 if (--nesting == 0) 744 break; 745 } 746 } 747 } 748 return p; 749 } 750 751 752 753 /* 754 * Test whether a specialized variable is set. 755 */ 756 757 STATIC int 758 varisset(name, nulok) 759 char *name; 760 int nulok; 761 { 762 if (*name == '!') 763 return backgndpid != -1; 764 else if (*name == '@' || *name == '*') { 765 if (*shellparam.p == NULL) 766 return 0; 767 768 if (nulok) { 769 char **av; 770 771 for (av = shellparam.p; *av; av++) 772 if (**av != '\0') 773 return 1; 774 return 0; 775 } 776 } else if (is_digit(*name)) { 777 char *ap; 778 int num = atoi(name); 779 780 if (num > shellparam.nparam) 781 return 0; 782 783 if (num == 0) 784 ap = arg0; 785 else 786 ap = shellparam.p[num - 1]; 787 788 if (nulok && (ap == NULL || *ap == '\0')) 789 return 0; 790 } 791 return 1; 792 } 793 794 795 796 /* 797 * Add the value of a specialized variable to the stack string. 798 */ 799 800 STATIC void 801 varvalue(name, quoted, allow_split) 802 char *name; 803 int quoted; 804 int allow_split; 805 { 806 int num; 807 char *p; 808 int i; 809 extern int oexitstatus; 810 char sep; 811 char **ap; 812 char const *syntax; 813 814 #define STRTODEST(p) \ 815 do {\ 816 if (allow_split) { \ 817 syntax = quoted? DQSYNTAX : BASESYNTAX; \ 818 while (*p) { \ 819 if (syntax[(int)*p] == CCTL) \ 820 STPUTC(CTLESC, expdest); \ 821 STPUTC(*p++, expdest); \ 822 } \ 823 } else \ 824 while (*p) \ 825 STPUTC(*p++, expdest); \ 826 } while (0) 827 828 829 switch (*name) { 830 case '$': 831 num = rootpid; 832 goto numvar; 833 case '?': 834 num = oexitstatus; 835 goto numvar; 836 case '#': 837 num = shellparam.nparam; 838 goto numvar; 839 case '!': 840 num = backgndpid; 841 numvar: 842 expdest = cvtnum(num, expdest); 843 break; 844 case '-': 845 for (i = 0 ; i < NOPTS ; i++) { 846 if (optlist[i].val) 847 STPUTC(optlist[i].letter, expdest); 848 } 849 break; 850 case '@': 851 if (allow_split && quoted) { 852 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 853 STRTODEST(p); 854 if (*ap) 855 STPUTC('\0', expdest); 856 } 857 break; 858 } 859 /* fall through */ 860 case '*': 861 if (ifsset() != 0) 862 sep = ifsval()[0]; 863 else 864 sep = ' '; 865 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 866 STRTODEST(p); 867 if (*ap && sep) 868 STPUTC(sep, expdest); 869 } 870 break; 871 case '0': 872 p = arg0; 873 STRTODEST(p); 874 break; 875 default: 876 if (is_digit(*name)) { 877 num = atoi(name); 878 if (num > 0 && num <= shellparam.nparam) { 879 p = shellparam.p[num - 1]; 880 STRTODEST(p); 881 } 882 } 883 break; 884 } 885 } 886 887 888 889 /* 890 * Record the the fact that we have to scan this region of the 891 * string for IFS characters. 892 */ 893 894 STATIC void 895 recordregion(start, end, nulonly) 896 int start; 897 int end; 898 int nulonly; 899 { 900 struct ifsregion *ifsp; 901 902 if (ifslastp == NULL) { 903 ifsp = &ifsfirst; 904 } else { 905 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 906 ifslastp->next = ifsp; 907 } 908 ifslastp = ifsp; 909 ifslastp->next = NULL; 910 ifslastp->begoff = start; 911 ifslastp->endoff = end; 912 ifslastp->nulonly = nulonly; 913 } 914 915 916 917 /* 918 * Break the argument string into pieces based upon IFS and add the 919 * strings to the argument list. The regions of the string to be 920 * searched for IFS characters have been stored by recordregion. 921 */ 922 STATIC void 923 ifsbreakup(string, arglist) 924 char *string; 925 struct arglist *arglist; 926 { 927 struct ifsregion *ifsp; 928 struct strlist *sp; 929 char *start; 930 char *p; 931 char *q; 932 char *ifs; 933 int ifsspc; 934 int nulonly; 935 936 937 start = string; 938 ifsspc = 0; 939 nulonly = 0; 940 if (ifslastp != NULL) { 941 ifsp = &ifsfirst; 942 do { 943 p = string + ifsp->begoff; 944 nulonly = ifsp->nulonly; 945 ifs = nulonly ? nullstr : 946 ( ifsset() ? ifsval() : " \t\n" ); 947 ifsspc = 0; 948 while (p < string + ifsp->endoff) { 949 q = p; 950 if (*p == CTLESC) 951 p++; 952 if (strchr(ifs, *p)) { 953 if (!nulonly) 954 ifsspc = (strchr(" \t\n", *p) != NULL); 955 /* Ignore IFS whitespace at start */ 956 if (q == start && ifsspc) { 957 p++; 958 start = p; 959 continue; 960 } 961 *q = '\0'; 962 sp = (struct strlist *)stalloc(sizeof *sp); 963 sp->text = start; 964 *arglist->lastp = sp; 965 arglist->lastp = &sp->next; 966 p++; 967 if (!nulonly) { 968 for (;;) { 969 if (p >= string + ifsp->endoff) { 970 break; 971 } 972 q = p; 973 if (*p == CTLESC) 974 p++; 975 if (strchr(ifs, *p) == NULL ) { 976 p = q; 977 break; 978 } else if (strchr(" \t\n",*p) == NULL) { 979 if (ifsspc) { 980 p++; 981 ifsspc = 0; 982 } else { 983 p = q; 984 break; 985 } 986 } else 987 p++; 988 } 989 } 990 start = p; 991 } else 992 p++; 993 } 994 } while ((ifsp = ifsp->next) != NULL); 995 if (*start || (!ifsspc && start > string && 996 (nulonly || 1))) { 997 sp = (struct strlist *)stalloc(sizeof *sp); 998 sp->text = start; 999 *arglist->lastp = sp; 1000 arglist->lastp = &sp->next; 1001 } 1002 } else { 1003 sp = (struct strlist *)stalloc(sizeof *sp); 1004 sp->text = start; 1005 *arglist->lastp = sp; 1006 arglist->lastp = &sp->next; 1007 } 1008 } 1009 1010 STATIC void 1011 ifsfree() 1012 { 1013 while (ifsfirst.next != NULL) { 1014 struct ifsregion *ifsp; 1015 INTOFF; 1016 ifsp = ifsfirst.next->next; 1017 ckfree(ifsfirst.next); 1018 ifsfirst.next = ifsp; 1019 INTON; 1020 } 1021 ifslastp = NULL; 1022 ifsfirst.next = NULL; 1023 } 1024 1025 1026 1027 /* 1028 * Expand shell metacharacters. At this point, the only control characters 1029 * should be escapes. The results are stored in the list exparg. 1030 */ 1031 1032 char *expdir; 1033 1034 1035 STATIC void 1036 expandmeta(str, flag) 1037 struct strlist *str; 1038 int flag; 1039 { 1040 char *p; 1041 struct strlist **savelastp; 1042 struct strlist *sp; 1043 char c; 1044 /* TODO - EXP_REDIR */ 1045 1046 while (str) { 1047 if (fflag) 1048 goto nometa; 1049 p = str->text; 1050 for (;;) { /* fast check for meta chars */ 1051 if ((c = *p++) == '\0') 1052 goto nometa; 1053 if (c == '*' || c == '?' || c == '[' || c == '!') 1054 break; 1055 } 1056 savelastp = exparg.lastp; 1057 INTOFF; 1058 if (expdir == NULL) { 1059 int i = strlen(str->text); 1060 expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */ 1061 } 1062 1063 expmeta(expdir, str->text); 1064 ckfree(expdir); 1065 expdir = NULL; 1066 INTON; 1067 if (exparg.lastp == savelastp) { 1068 /* 1069 * no matches 1070 */ 1071 nometa: 1072 *exparg.lastp = str; 1073 rmescapes(str->text); 1074 exparg.lastp = &str->next; 1075 } else { 1076 *exparg.lastp = NULL; 1077 *savelastp = sp = expsort(*savelastp); 1078 while (sp->next != NULL) 1079 sp = sp->next; 1080 exparg.lastp = &sp->next; 1081 } 1082 str = str->next; 1083 } 1084 } 1085 1086 1087 /* 1088 * Do metacharacter (i.e. *, ?, [...]) expansion. 1089 */ 1090 1091 STATIC void 1092 expmeta(enddir, name) 1093 char *enddir; 1094 char *name; 1095 { 1096 char *p; 1097 char *q; 1098 char *start; 1099 char *endname; 1100 int metaflag; 1101 struct stat statb; 1102 DIR *dirp; 1103 struct dirent *dp; 1104 int atend; 1105 int matchdot; 1106 1107 metaflag = 0; 1108 start = name; 1109 for (p = name ; ; p++) { 1110 if (*p == '*' || *p == '?') 1111 metaflag = 1; 1112 else if (*p == '[') { 1113 q = p + 1; 1114 if (*q == '!') 1115 q++; 1116 for (;;) { 1117 while (*q == CTLQUOTEMARK) 1118 q++; 1119 if (*q == CTLESC) 1120 q++; 1121 if (*q == '/' || *q == '\0') 1122 break; 1123 if (*++q == ']') { 1124 metaflag = 1; 1125 break; 1126 } 1127 } 1128 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 1129 metaflag = 1; 1130 } else if (*p == '\0') 1131 break; 1132 else if (*p == CTLQUOTEMARK) 1133 continue; 1134 else if (*p == CTLESC) 1135 p++; 1136 if (*p == '/') { 1137 if (metaflag) 1138 break; 1139 start = p + 1; 1140 } 1141 } 1142 if (metaflag == 0) { /* we've reached the end of the file name */ 1143 if (enddir != expdir) 1144 metaflag++; 1145 for (p = name ; ; p++) { 1146 if (*p == CTLQUOTEMARK) 1147 continue; 1148 if (*p == CTLESC) 1149 p++; 1150 *enddir++ = *p; 1151 if (*p == '\0') 1152 break; 1153 } 1154 if (metaflag == 0 || stat(expdir, &statb) >= 0) 1155 addfname(expdir); 1156 return; 1157 } 1158 endname = p; 1159 if (start != name) { 1160 p = name; 1161 while (p < start) { 1162 while (*p == CTLQUOTEMARK) 1163 p++; 1164 if (*p == CTLESC) 1165 p++; 1166 *enddir++ = *p++; 1167 } 1168 } 1169 if (enddir == expdir) { 1170 p = "."; 1171 } else if (enddir == expdir + 1 && *expdir == '/') { 1172 p = "/"; 1173 } else { 1174 p = expdir; 1175 enddir[-1] = '\0'; 1176 } 1177 if ((dirp = opendir(p)) == NULL) 1178 return; 1179 if (enddir != expdir) 1180 enddir[-1] = '/'; 1181 if (*endname == 0) { 1182 atend = 1; 1183 } else { 1184 atend = 0; 1185 *endname++ = '\0'; 1186 } 1187 matchdot = 0; 1188 p = start; 1189 while (*p == CTLQUOTEMARK) 1190 p++; 1191 if (*p == CTLESC) 1192 p++; 1193 if (*p == '.') 1194 matchdot++; 1195 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 1196 if (dp->d_name[0] == '.' && ! matchdot) 1197 continue; 1198 if (patmatch(start, dp->d_name)) { 1199 if (atend) { 1200 scopy(dp->d_name, enddir); 1201 addfname(expdir); 1202 } else { 1203 char *q; 1204 for (p = enddir, q = dp->d_name; 1205 (*p++ = *q++) != '\0';) 1206 continue; 1207 p[-1] = '/'; 1208 expmeta(p, endname); 1209 } 1210 } 1211 } 1212 closedir(dirp); 1213 if (! atend) 1214 endname[-1] = '/'; 1215 } 1216 1217 1218 /* 1219 * Add a file name to the list. 1220 */ 1221 1222 STATIC void 1223 addfname(name) 1224 char *name; 1225 { 1226 char *p; 1227 struct strlist *sp; 1228 1229 p = stalloc(strlen(name) + 1); 1230 scopy(name, p); 1231 sp = (struct strlist *)stalloc(sizeof *sp); 1232 sp->text = p; 1233 *exparg.lastp = sp; 1234 exparg.lastp = &sp->next; 1235 } 1236 1237 1238 /* 1239 * Sort the results of file name expansion. It calculates the number of 1240 * strings to sort and then calls msort (short for merge sort) to do the 1241 * work. 1242 */ 1243 1244 STATIC struct strlist * 1245 expsort(str) 1246 struct strlist *str; 1247 { 1248 int len; 1249 struct strlist *sp; 1250 1251 len = 0; 1252 for (sp = str ; sp ; sp = sp->next) 1253 len++; 1254 return msort(str, len); 1255 } 1256 1257 1258 STATIC struct strlist * 1259 msort(list, len) 1260 struct strlist *list; 1261 int len; 1262 { 1263 struct strlist *p, *q = NULL; 1264 struct strlist **lpp; 1265 int half; 1266 int n; 1267 1268 if (len <= 1) 1269 return list; 1270 half = len >> 1; 1271 p = list; 1272 for (n = half ; --n >= 0 ; ) { 1273 q = p; 1274 p = p->next; 1275 } 1276 q->next = NULL; /* terminate first half of list */ 1277 q = msort(list, half); /* sort first half of list */ 1278 p = msort(p, len - half); /* sort second half */ 1279 lpp = &list; 1280 for (;;) { 1281 if (strcmp(p->text, q->text) < 0) { 1282 *lpp = p; 1283 lpp = &p->next; 1284 if ((p = *lpp) == NULL) { 1285 *lpp = q; 1286 break; 1287 } 1288 } else { 1289 *lpp = q; 1290 lpp = &q->next; 1291 if ((q = *lpp) == NULL) { 1292 *lpp = p; 1293 break; 1294 } 1295 } 1296 } 1297 return list; 1298 } 1299 1300 1301 1302 /* 1303 * Returns true if the pattern matches the string. 1304 */ 1305 1306 int 1307 patmatch(pattern, string) 1308 char *pattern; 1309 char *string; 1310 { 1311 #ifdef notdef 1312 if (pattern[0] == '!' && pattern[1] == '!') 1313 return 1 - pmatch(pattern + 2, string); 1314 else 1315 #endif 1316 return pmatch(pattern, string); 1317 } 1318 1319 1320 STATIC int 1321 pmatch(pattern, string) 1322 char *pattern; 1323 char *string; 1324 { 1325 char *p, *q; 1326 char c; 1327 1328 p = pattern; 1329 q = string; 1330 for (;;) { 1331 switch (c = *p++) { 1332 case '\0': 1333 goto breakloop; 1334 case CTLESC: 1335 if (*q++ != *p++) 1336 return 0; 1337 break; 1338 case CTLQUOTEMARK: 1339 continue; 1340 case '?': 1341 if (*q++ == '\0') 1342 return 0; 1343 break; 1344 case '*': 1345 c = *p; 1346 while (c == CTLQUOTEMARK || c == '*') 1347 c = *++p; 1348 if (c != CTLESC && c != CTLQUOTEMARK && 1349 c != '?' && c != '*' && c != '[') { 1350 while (*q != c) { 1351 if (*q == '\0') 1352 return 0; 1353 q++; 1354 } 1355 } 1356 do { 1357 if (pmatch(p, q)) 1358 return 1; 1359 } while (*q++ != '\0'); 1360 return 0; 1361 case '[': { 1362 char *endp; 1363 int invert, found; 1364 char chr; 1365 1366 endp = p; 1367 if (*endp == '!') 1368 endp++; 1369 for (;;) { 1370 while (*endp == CTLQUOTEMARK) 1371 endp++; 1372 if (*endp == '\0') 1373 goto dft; /* no matching ] */ 1374 if (*endp == CTLESC) 1375 endp++; 1376 if (*++endp == ']') 1377 break; 1378 } 1379 invert = 0; 1380 if (*p == '!') { 1381 invert++; 1382 p++; 1383 } 1384 found = 0; 1385 chr = *q++; 1386 if (chr == '\0') 1387 return 0; 1388 c = *p++; 1389 do { 1390 if (c == CTLQUOTEMARK) 1391 continue; 1392 if (c == CTLESC) 1393 c = *p++; 1394 if (*p == '-' && p[1] != ']') { 1395 p++; 1396 while (*p == CTLQUOTEMARK) 1397 p++; 1398 if (*p == CTLESC) 1399 p++; 1400 if (chr >= c && chr <= *p) 1401 found = 1; 1402 p++; 1403 } else { 1404 if (chr == c) 1405 found = 1; 1406 } 1407 } while ((c = *p++) != ']'); 1408 if (found == invert) 1409 return 0; 1410 break; 1411 } 1412 dft: default: 1413 if (*q++ != c) 1414 return 0; 1415 break; 1416 } 1417 } 1418 breakloop: 1419 if (*q != '\0') 1420 return 0; 1421 return 1; 1422 } 1423 1424 1425 1426 /* 1427 * Remove any CTLESC characters from a string. 1428 */ 1429 1430 void 1431 rmescapes(str) 1432 char *str; 1433 { 1434 char *p, *q; 1435 1436 p = str; 1437 while (*p != CTLESC && *p != CTLQUOTEMARK) { 1438 if (*p++ == '\0') 1439 return; 1440 } 1441 q = p; 1442 while (*p) { 1443 if (*p == CTLQUOTEMARK) { 1444 p++; 1445 continue; 1446 } 1447 if (*p == CTLESC) 1448 p++; 1449 *q++ = *p++; 1450 } 1451 *q = '\0'; 1452 } 1453 1454 1455 1456 /* 1457 * See if a pattern matches in a case statement. 1458 */ 1459 1460 int 1461 casematch(pattern, val) 1462 union node *pattern; 1463 char *val; 1464 { 1465 struct stackmark smark; 1466 int result; 1467 char *p; 1468 1469 setstackmark(&smark); 1470 argbackq = pattern->narg.backquote; 1471 STARTSTACKSTR(expdest); 1472 ifslastp = NULL; 1473 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); 1474 STPUTC('\0', expdest); 1475 p = grabstackstr(expdest); 1476 result = patmatch(p, val); 1477 popstackmark(&smark); 1478 return result; 1479 } 1480 1481 /* 1482 * Our own itoa(). 1483 */ 1484 1485 STATIC char * 1486 cvtnum(num, buf) 1487 int num; 1488 char *buf; 1489 { 1490 char temp[32]; 1491 int neg = num < 0; 1492 char *p = temp + 31; 1493 1494 temp[31] = '\0'; 1495 1496 do { 1497 *--p = num % 10 + '0'; 1498 } while ((num /= 10) != 0); 1499 1500 if (neg) 1501 *--p = '-'; 1502 1503 while (*p) 1504 STPUTC(*p++, buf); 1505 return buf; 1506 } 1507