expand.c revision 17987
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 * $Id: expand.c,v 1.6 1996/08/12 19:31:11 ache Exp $ 37 */ 38 39#ifndef lint 40static char sccsid[] = "@(#)expand.c 8.5 (Berkeley) 5/15/95"; 41#endif /* not lint */ 42 43#include <sys/types.h> 44#include <sys/time.h> 45#include <sys/stat.h> 46#include <errno.h> 47#include <dirent.h> 48#include <unistd.h> 49#include <pwd.h> 50#include <stdlib.h> 51#include <locale.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 81struct 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 89char *expdest; /* output of current string */ 90struct nodelist *argbackq; /* list of back quote expressions */ 91struct ifsregion ifsfirst; /* first struct in list of ifs regions */ 92struct ifsregion *ifslastp; /* last struct in list */ 93struct arglist exparg; /* holds expanded arg list */ 94 95STATIC void argstr __P((char *, int)); 96STATIC char *exptilde __P((char *, int)); 97STATIC void expbackq __P((union node *, int, int)); 98STATIC int subevalvar __P((char *, char *, int, int, int)); 99STATIC char *evalvar __P((char *, int)); 100STATIC int varisset __P((int)); 101STATIC void varvalue __P((int, int, int)); 102STATIC void recordregion __P((int, int, int)); 103STATIC void ifsbreakup __P((char *, struct arglist *)); 104STATIC void expandmeta __P((struct strlist *, int)); 105STATIC void expmeta __P((char *, char *)); 106STATIC void addfname __P((char *)); 107STATIC struct strlist *expsort __P((struct strlist *)); 108STATIC struct strlist *msort __P((struct strlist *, int)); 109STATIC int pmatch __P((char *, char *)); 110STATIC char *cvtnum __P((int, char *)); 111 112/* 113 * Expand shell variables and backquotes inside a here document. 114 */ 115 116void 117expandhere(arg, fd) 118 union node *arg; /* the document */ 119 int fd; /* where to write the expanded version */ 120 { 121 herefd = fd; 122 expandarg(arg, (struct arglist *)NULL, 0); 123 xwrite(fd, stackblock(), expdest - stackblock()); 124} 125 126 127/* 128 * Perform variable substitution and command substitution on an argument, 129 * placing the resulting list of arguments in arglist. If EXP_FULL is true, 130 * perform splitting and file name expansion. When arglist is NULL, perform 131 * here document expansion. 132 */ 133 134void 135expandarg(arg, arglist, flag) 136 union node *arg; 137 struct arglist *arglist; 138 int flag; 139{ 140 struct strlist *sp; 141 char *p; 142 143 argbackq = arg->narg.backquote; 144 STARTSTACKSTR(expdest); 145 ifsfirst.next = NULL; 146 ifslastp = NULL; 147 argstr(arg->narg.text, flag); 148 if (arglist == NULL) { 149 return; /* here document expanded */ 150 } 151 STPUTC('\0', expdest); 152 p = grabstackstr(expdest); 153 exparg.lastp = &exparg.list; 154 /* 155 * TODO - EXP_REDIR 156 */ 157 if (flag & EXP_FULL) { 158 ifsbreakup(p, &exparg); 159 *exparg.lastp = NULL; 160 exparg.lastp = &exparg.list; 161 expandmeta(exparg.list, flag); 162 } else { 163 if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */ 164 rmescapes(p); 165 sp = (struct strlist *)stalloc(sizeof (struct strlist)); 166 sp->text = p; 167 *exparg.lastp = sp; 168 exparg.lastp = &sp->next; 169 } 170 while (ifsfirst.next != NULL) { 171 struct ifsregion *ifsp; 172 INTOFF; 173 ifsp = ifsfirst.next->next; 174 ckfree(ifsfirst.next); 175 ifsfirst.next = ifsp; 176 INTON; 177 } 178 *exparg.lastp = NULL; 179 if (exparg.list) { 180 *arglist->lastp = exparg.list; 181 arglist->lastp = exparg.lastp; 182 } 183} 184 185 186 187/* 188 * Perform variable and command substitution. If EXP_FULL is set, output CTLESC 189 * characters to allow for further processing. Otherwise treat 190 * $@ like $* since no splitting will be performed. 191 */ 192 193STATIC void 194argstr(p, flag) 195 register char *p; 196 int flag; 197{ 198 register char c; 199 int quotes = flag & (EXP_FULL | EXP_CASE); /* do CTLESC */ 200 int firsteq = 1; 201 202 if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE))) 203 p = exptilde(p, flag); 204 for (;;) { 205 switch (c = *p++) { 206 case '\0': 207 case CTLENDVAR: /* ??? */ 208 goto breakloop; 209 case CTLESC: 210 if (quotes) 211 STPUTC(c, expdest); 212 c = *p++; 213 STPUTC(c, expdest); 214 break; 215 case CTLVAR: 216 p = evalvar(p, flag); 217 break; 218 case CTLBACKQ: 219 case CTLBACKQ|CTLQUOTE: 220 expbackq(argbackq->n, c & CTLQUOTE, flag); 221 argbackq = argbackq->next; 222 break; 223 case CTLENDARI: 224 expari(flag); 225 break; 226 case ':': 227 case '=': 228 /* 229 * sort of a hack - expand tildes in variable 230 * assignments (after the first '=' and after ':'s). 231 */ 232 STPUTC(c, expdest); 233 if (flag & EXP_VARTILDE && *p == '~') { 234 if (c == '=') { 235 if (firsteq) 236 firsteq = 0; 237 else 238 break; 239 } 240 p = exptilde(p, flag); 241 } 242 break; 243 default: 244 STPUTC(c, expdest); 245 } 246 } 247breakloop:; 248} 249 250STATIC char * 251exptilde(p, flag) 252 char *p; 253 int flag; 254{ 255 char c, *startp = p; 256 struct passwd *pw; 257 char *home; 258 int quotes = flag & (EXP_FULL | EXP_CASE); 259 260 while ((c = *p) != '\0') { 261 switch(c) { 262 case CTLESC: 263 return (startp); 264 case ':': 265 if (flag & EXP_VARTILDE) 266 goto done; 267 break; 268 case '/': 269 goto done; 270 } 271 p++; 272 } 273done: 274 *p = '\0'; 275 if (*(startp+1) == '\0') { 276 if ((home = lookupvar("HOME")) == NULL) 277 goto lose; 278 } else { 279 if ((pw = getpwnam(startp+1)) == NULL) 280 goto lose; 281 home = pw->pw_dir; 282 } 283 if (*home == '\0') 284 goto lose; 285 *p = c; 286 while ((c = *home++) != '\0') { 287 if (quotes && SQSYNTAX[c] == CCTL) 288 STPUTC(CTLESC, expdest); 289 STPUTC(c, expdest); 290 } 291 return (p); 292lose: 293 *p = c; 294 return (startp); 295} 296 297 298/* 299 * Expand arithmetic expression. Backup to start of expression, 300 * evaluate, place result in (backed up) result, adjust string position. 301 */ 302void 303expari(flag) 304 int flag; 305{ 306 char *p, *start; 307 int result; 308 int quotes = flag & (EXP_FULL | EXP_CASE); 309 310 /* 311 * This routine is slightly over-compilcated for 312 * efficiency. First we make sure there is 313 * enough space for the result, which may be bigger 314 * than the expression if we add exponentation. Next we 315 * scan backwards looking for the start of arithmetic. If the 316 * next previous character is a CTLESC character, then we 317 * have to rescan starting from the beginning since CTLESC 318 * characters have to be processed left to right. 319 */ 320 CHECKSTRSPACE(8, expdest); 321 USTPUTC('\0', expdest); 322 start = stackblock(); 323 p = expdest; 324 while (*p != CTLARI && p >= start) 325 --p; 326 if (*p != CTLARI) 327 error("missing CTLARI (shouldn't happen)"); 328 if (p > start && *(p-1) == CTLESC) 329 for (p = start; *p != CTLARI; p++) 330 if (*p == CTLESC) 331 p++; 332 if (quotes) 333 rmescapes(p+1); 334 result = arith(p+1); 335 fmtstr(p, 10, "%d", result); 336 while (*p++) 337 ; 338 result = expdest - p + 1; 339 STADJUST(-result, expdest); 340} 341 342 343/* 344 * Expand stuff in backwards quotes. 345 */ 346 347STATIC void 348expbackq(cmd, quoted, flag) 349 union node *cmd; 350 int quoted; 351 int flag; 352{ 353 struct backcmd in; 354 int i; 355 char buf[128]; 356 char *p; 357 char *dest = expdest; 358 struct ifsregion saveifs, *savelastp; 359 struct nodelist *saveargbackq; 360 char lastc; 361 int startloc = dest - stackblock(); 362 char const *syntax = quoted? DQSYNTAX : BASESYNTAX; 363 int saveherefd; 364 int quotes = flag & (EXP_FULL | EXP_CASE); 365 366 INTOFF; 367 saveifs = ifsfirst; 368 savelastp = ifslastp; 369 saveargbackq = argbackq; 370 saveherefd = herefd; 371 herefd = -1; 372 p = grabstackstr(dest); 373 evalbackcmd(cmd, &in); 374 ungrabstackstr(p, dest); 375 ifsfirst = saveifs; 376 ifslastp = savelastp; 377 argbackq = saveargbackq; 378 herefd = saveherefd; 379 380 p = in.buf; 381 lastc = '\0'; 382 for (;;) { 383 if (--in.nleft < 0) { 384 if (in.fd < 0) 385 break; 386 while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR); 387 TRACE(("expbackq: read returns %d\n", i)); 388 if (i <= 0) 389 break; 390 p = buf; 391 in.nleft = i - 1; 392 } 393 lastc = *p++; 394 if (lastc != '\0') { 395 if (quotes && syntax[lastc] == CCTL) 396 STPUTC(CTLESC, dest); 397 STPUTC(lastc, dest); 398 } 399 } 400 401 /* Eat all trailing newlines */ 402 for (p--; lastc == '\n'; lastc = *--p) 403 STUNPUTC(dest); 404 405 if (in.fd >= 0) 406 close(in.fd); 407 if (in.buf) 408 ckfree(in.buf); 409 if (in.jp) 410 exitstatus = waitforjob(in.jp); 411 if (quoted == 0) 412 recordregion(startloc, dest - stackblock(), 0); 413 TRACE(("evalbackq: size=%d: \"%.*s\"\n", 414 (dest - stackblock()) - startloc, 415 (dest - stackblock()) - startloc, 416 stackblock() + startloc)); 417 expdest = dest; 418 INTON; 419} 420 421 422 423STATIC int 424subevalvar(p, str, subtype, startloc, varflags) 425 char *p; 426 char *str; 427 int subtype; 428 int startloc; 429 int varflags; 430{ 431 432 char *startp; 433 char *loc = NULL; 434 int c = 0; 435 int saveherefd = herefd; 436 struct nodelist *saveargbackq = argbackq; 437 herefd = -1; 438 argstr(p, 0); 439 STACKSTRNUL(expdest); 440 herefd = saveherefd; 441 argbackq = saveargbackq; 442 startp = stackblock() + startloc; 443 444 switch (subtype) { 445 case VSASSIGN: 446 setvar(str, startp, 0); 447 STADJUST(startp - expdest, expdest); 448 varflags &= ~VSNUL; 449 if (c != 0) 450 *loc = c; 451 return 1; 452 453 case VSQUESTION: 454 if (*p != CTLENDVAR) { 455 outfmt(&errout, "%s\n", startp); 456 error((char *)NULL); 457 } 458 error("%.*s: parameter %snot set", p - str - 1, 459 str, (varflags & VSNUL) ? "null or " 460 : nullstr); 461 return 0; 462 463 case VSTRIMLEFT: 464 for (loc = startp; loc < str - 1; loc++) { 465 c = *loc; 466 *loc = '\0'; 467 if (patmatch(str, startp)) { 468 *loc = c; 469 goto recordleft; 470 } 471 *loc = c; 472 } 473 return 0; 474 475 case VSTRIMLEFTMAX: 476 for (loc = str - 1; loc >= startp; loc--) { 477 c = *loc; 478 *loc = '\0'; 479 if (patmatch(str, startp)) { 480 *loc = c; 481 goto recordleft; 482 } 483 *loc = c; 484 } 485 return 0; 486 487 case VSTRIMRIGHT: 488 for (loc = str - 1; loc >= startp; loc--) { 489 if (patmatch(str, loc)) { 490 expdest = loc; 491 return 1; 492 } 493 } 494 return 0; 495 496 case VSTRIMRIGHTMAX: 497 for (loc = startp; loc < str - 1; loc++) { 498 if (patmatch(str, loc)) { 499 expdest = loc; 500 return 1; 501 } 502 } 503 return 0; 504 505 506 default: 507 abort(); 508 } 509 510recordleft: 511 expdest = (str - 1) - (loc - startp); 512 while (loc != str - 1) 513 *startp++ = *loc++; 514 return 1; 515} 516 517 518/* 519 * Expand a variable, and return a pointer to the next character in the 520 * input string. 521 */ 522 523STATIC char * 524evalvar(p, flag) 525 char *p; 526 int flag; 527{ 528 int subtype; 529 int varflags; 530 char *var; 531 char *val; 532 char *pat; 533 int c; 534 int set; 535 int special; 536 int startloc; 537 int varlen; 538 int easy; 539 int quotes = flag & (EXP_FULL | EXP_CASE); 540 541 varflags = *p++; 542 subtype = varflags & VSTYPE; 543 var = p; 544 special = 0; 545 if (! is_name(*p)) 546 special = 1; 547 p = strchr(p, '=') + 1; 548again: /* jump here after setting a variable with ${var=text} */ 549 if (special) { 550 set = varisset(*var); 551 val = NULL; 552 } else { 553 val = lookupvar(var); 554 if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) { 555 val = NULL; 556 set = 0; 557 } else 558 set = 1; 559 } 560 varlen = 0; 561 startloc = expdest - stackblock(); 562 if (set && subtype != VSPLUS) { 563 /* insert the value of the variable */ 564 if (special) { 565 char *exp, *oexpdest = expdest; 566 varvalue(*var, varflags & VSQUOTE, flag & EXP_FULL); 567 if (subtype == VSLENGTH) { 568 for (exp = oexpdest;exp != expdest; exp++) 569 varlen++; 570 expdest = oexpdest; 571 } 572 } else { 573 char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX 574 : BASESYNTAX; 575 576 if (subtype == VSLENGTH) { 577 for (;*val; val++) 578 varlen++; 579 } 580 else { 581 while (*val) { 582 if (quotes && syntax[*val] == CCTL) 583 STPUTC(CTLESC, expdest); 584 STPUTC(*val++, expdest); 585 } 586 587 } 588 } 589 } 590 591 if (subtype == VSPLUS) 592 set = ! set; 593 594 easy = ((varflags & VSQUOTE) == 0 || 595 (*var == '@' && shellparam.nparam != 1)); 596 597 598 switch (subtype) { 599 case VSLENGTH: 600 expdest = cvtnum(varlen, expdest); 601 goto record; 602 603 case VSNORMAL: 604 if (!easy) 605 break; 606record: 607 recordregion(startloc, expdest - stackblock(), 608 varflags & VSQUOTE); 609 break; 610 611 case VSPLUS: 612 case VSMINUS: 613 if (!set) { 614 argstr(p, flag); 615 break; 616 } 617 if (easy) 618 goto record; 619 break; 620 621 case VSTRIMLEFT: 622 case VSTRIMLEFTMAX: 623 case VSTRIMRIGHT: 624 case VSTRIMRIGHTMAX: 625 if (!set) 626 break; 627 /* 628 * Terminate the string and start recording the pattern 629 * right after it 630 */ 631 STPUTC('\0', expdest); 632 pat = expdest; 633 if (subevalvar(p, pat, subtype, startloc, varflags)) 634 goto record; 635 break; 636 637 case VSASSIGN: 638 case VSQUESTION: 639 if (!set) { 640 if (subevalvar(p, var, subtype, startloc, varflags)) 641 goto again; 642 break; 643 } 644 if (easy) 645 goto record; 646 break; 647 648 default: 649 abort(); 650 } 651 652 if (subtype != VSNORMAL) { /* skip to end of alternative */ 653 int nesting = 1; 654 for (;;) { 655 if ((c = *p++) == CTLESC) 656 p++; 657 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { 658 if (set) 659 argbackq = argbackq->next; 660 } else if (c == CTLVAR) { 661 if ((*p++ & VSTYPE) != VSNORMAL) 662 nesting++; 663 } else if (c == CTLENDVAR) { 664 if (--nesting == 0) 665 break; 666 } 667 } 668 } 669 return p; 670} 671 672 673 674/* 675 * Test whether a specialized variable is set. 676 */ 677 678STATIC int 679varisset(name) 680 char name; 681 { 682 char **ap; 683 684 if (name == '!') { 685 if (backgndpid == -1) 686 return 0; 687 } else if (name == '@' || name == '*') { 688 if (*shellparam.p == NULL) 689 return 0; 690 } else if ((unsigned)(name -= '1') <= '9' - '1') { 691 ap = shellparam.p; 692 do { 693 if (*ap++ == NULL) 694 return 0; 695 } while (--name >= 0); 696 } 697 return 1; 698} 699 700 701 702/* 703 * Add the value of a specialized variable to the stack string. 704 */ 705 706STATIC void 707varvalue(name, quoted, allow_split) 708 char name; 709 int quoted; 710 int allow_split; 711{ 712 int num; 713 char *p; 714 int i; 715 extern int oexitstatus; 716 char sep; 717 char **ap; 718 char const *syntax; 719 720#define STRTODEST(p) \ 721 do {\ 722 if (allow_split) { \ 723 syntax = quoted? DQSYNTAX : BASESYNTAX; \ 724 while (*p) { \ 725 if (syntax[*p] == CCTL) \ 726 STPUTC(CTLESC, expdest); \ 727 STPUTC(*p++, expdest); \ 728 } \ 729 } else \ 730 while (*p) \ 731 STPUTC(*p++, expdest); \ 732 } while (0) 733 734 735 switch (name) { 736 case '$': 737 num = rootpid; 738 goto numvar; 739 case '?': 740 num = oexitstatus; 741 goto numvar; 742 case '#': 743 num = shellparam.nparam; 744 goto numvar; 745 case '!': 746 num = backgndpid; 747numvar: 748 expdest = cvtnum(num, expdest); 749 break; 750 case '-': 751 for (i = 0 ; i < NOPTS ; i++) { 752 if (optlist[i].val) 753 STPUTC(optlist[i].letter, expdest); 754 } 755 break; 756 case '@': 757 if (allow_split) { 758 sep = '\0'; 759 goto allargs; 760 } 761 /* fall through */ 762 case '*': 763 sep = ' '; 764allargs: 765 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 766 STRTODEST(p); 767 if (*ap) 768 STPUTC(sep, expdest); 769 } 770 break; 771 case '0': 772 p = arg0; 773 STRTODEST(p); 774 break; 775 default: 776 if ((unsigned)(name -= '1') <= '9' - '1') { 777 p = shellparam.p[name]; 778 STRTODEST(p); 779 } 780 break; 781 } 782} 783 784 785 786/* 787 * Record the the fact that we have to scan this region of the 788 * string for IFS characters. 789 */ 790 791STATIC void 792recordregion(start, end, nulonly) 793 int start; 794 int end; 795 int nulonly; 796{ 797 register struct ifsregion *ifsp; 798 799 if (ifslastp == NULL) { 800 ifsp = &ifsfirst; 801 } else { 802 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 803 ifslastp->next = ifsp; 804 } 805 ifslastp = ifsp; 806 ifslastp->next = NULL; 807 ifslastp->begoff = start; 808 ifslastp->endoff = end; 809 ifslastp->nulonly = nulonly; 810} 811 812 813 814/* 815 * Break the argument string into pieces based upon IFS and add the 816 * strings to the argument list. The regions of the string to be 817 * searched for IFS characters have been stored by recordregion. 818 */ 819STATIC void 820ifsbreakup(string, arglist) 821 char *string; 822 struct arglist *arglist; 823 { 824 struct ifsregion *ifsp; 825 struct strlist *sp; 826 char *start; 827 register char *p; 828 char *q; 829 char *ifs; 830 int ifsspc; 831 832 833 start = string; 834 if (ifslastp != NULL) { 835 ifsp = &ifsfirst; 836 do { 837 p = string + ifsp->begoff; 838 ifs = ifsp->nulonly? nullstr : ifsval(); 839 ifsspc = strchr(ifs, ' ') != NULL; 840 while (p < string + ifsp->endoff) { 841 q = p; 842 if (*p == CTLESC) 843 p++; 844 if (strchr(ifs, *p++)) { 845 if (q > start || !ifsspc) { 846 *q = '\0'; 847 sp = (struct strlist *)stalloc(sizeof *sp); 848 sp->text = start; 849 *arglist->lastp = sp; 850 arglist->lastp = &sp->next; 851 } 852 if (ifsspc) { 853 for (;;) { 854 if (p >= string + ifsp->endoff) 855 break; 856 q = p; 857 if (*p == CTLESC) 858 p++; 859 if (strchr(ifs, *p++) == NULL) { 860 p = q; 861 break; 862 } 863 } 864 } 865 start = p; 866 } 867 } 868 } while ((ifsp = ifsp->next) != NULL); 869 if (*start || (!ifsspc && start > string)) { 870 sp = (struct strlist *)stalloc(sizeof *sp); 871 sp->text = start; 872 *arglist->lastp = sp; 873 arglist->lastp = &sp->next; 874 } 875 } else { 876 sp = (struct strlist *)stalloc(sizeof *sp); 877 sp->text = start; 878 *arglist->lastp = sp; 879 arglist->lastp = &sp->next; 880 } 881} 882 883 884 885/* 886 * Expand shell metacharacters. At this point, the only control characters 887 * should be escapes. The results are stored in the list exparg. 888 */ 889 890char *expdir; 891 892 893STATIC void 894expandmeta(str, flag) 895 struct strlist *str; 896 int flag; 897{ 898 char *p; 899 struct strlist **savelastp; 900 struct strlist *sp; 901 char c; 902 /* TODO - EXP_REDIR */ 903 904 while (str) { 905 if (fflag) 906 goto nometa; 907 p = str->text; 908 for (;;) { /* fast check for meta chars */ 909 if ((c = *p++) == '\0') 910 goto nometa; 911 if (c == '*' || c == '?' || c == '[' || c == '!') 912 break; 913 } 914 savelastp = exparg.lastp; 915 INTOFF; 916 if (expdir == NULL) { 917 int i = strlen(str->text); 918 expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */ 919 } 920 921 expmeta(expdir, str->text); 922 ckfree(expdir); 923 expdir = NULL; 924 INTON; 925 if (exparg.lastp == savelastp) { 926 /* 927 * no matches 928 */ 929nometa: 930 *exparg.lastp = str; 931 rmescapes(str->text); 932 exparg.lastp = &str->next; 933 } else { 934 *exparg.lastp = NULL; 935 *savelastp = sp = expsort(*savelastp); 936 while (sp->next != NULL) 937 sp = sp->next; 938 exparg.lastp = &sp->next; 939 } 940 str = str->next; 941 } 942} 943 944 945/* 946 * Do metacharacter (i.e. *, ?, [...]) expansion. 947 */ 948 949STATIC void 950expmeta(enddir, name) 951 char *enddir; 952 char *name; 953 { 954 register char *p; 955 char *q; 956 char *start; 957 char *endname; 958 int metaflag; 959 struct stat statb; 960 DIR *dirp; 961 struct dirent *dp; 962 int atend; 963 int matchdot; 964 965 metaflag = 0; 966 start = name; 967 for (p = name ; ; p++) { 968 if (*p == '*' || *p == '?') 969 metaflag = 1; 970 else if (*p == '[') { 971 q = p + 1; 972 if (*q == '!') 973 q++; 974 for (;;) { 975 if (*q == CTLESC) 976 q++; 977 if (*q == '/' || *q == '\0') 978 break; 979 if (*++q == ']') { 980 metaflag = 1; 981 break; 982 } 983 } 984 } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) { 985 metaflag = 1; 986 } else if (*p == '\0') 987 break; 988 else if (*p == CTLESC) 989 p++; 990 if (*p == '/') { 991 if (metaflag) 992 break; 993 start = p + 1; 994 } 995 } 996 if (metaflag == 0) { /* we've reached the end of the file name */ 997 if (enddir != expdir) 998 metaflag++; 999 for (p = name ; ; p++) { 1000 if (*p == CTLESC) 1001 p++; 1002 *enddir++ = *p; 1003 if (*p == '\0') 1004 break; 1005 } 1006 if (metaflag == 0 || stat(expdir, &statb) >= 0) 1007 addfname(expdir); 1008 return; 1009 } 1010 endname = p; 1011 if (start != name) { 1012 p = name; 1013 while (p < start) { 1014 if (*p == CTLESC) 1015 p++; 1016 *enddir++ = *p++; 1017 } 1018 } 1019 if (enddir == expdir) { 1020 p = "."; 1021 } else if (enddir == expdir + 1 && *expdir == '/') { 1022 p = "/"; 1023 } else { 1024 p = expdir; 1025 enddir[-1] = '\0'; 1026 } 1027 if ((dirp = opendir(p)) == NULL) 1028 return; 1029 if (enddir != expdir) 1030 enddir[-1] = '/'; 1031 if (*endname == 0) { 1032 atend = 1; 1033 } else { 1034 atend = 0; 1035 *endname++ = '\0'; 1036 } 1037 matchdot = 0; 1038 if (start[0] == '.' || (start[0] == CTLESC && start[1] == '.')) 1039 matchdot++; 1040 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 1041 if (dp->d_name[0] == '.' && ! matchdot) 1042 continue; 1043 if (patmatch(start, dp->d_name)) { 1044 if (atend) { 1045 scopy(dp->d_name, enddir); 1046 addfname(expdir); 1047 } else { 1048 char *q; 1049 for (p = enddir, q = dp->d_name; 1050 (*p++ = *q++) != '\0';) 1051 continue; 1052 p[-1] = '/'; 1053 expmeta(p, endname); 1054 } 1055 } 1056 } 1057 closedir(dirp); 1058 if (! atend) 1059 endname[-1] = '/'; 1060} 1061 1062 1063/* 1064 * Add a file name to the list. 1065 */ 1066 1067STATIC void 1068addfname(name) 1069 char *name; 1070 { 1071 char *p; 1072 struct strlist *sp; 1073 1074 p = stalloc(strlen(name) + 1); 1075 scopy(name, p); 1076 sp = (struct strlist *)stalloc(sizeof *sp); 1077 sp->text = p; 1078 *exparg.lastp = sp; 1079 exparg.lastp = &sp->next; 1080} 1081 1082 1083/* 1084 * Sort the results of file name expansion. It calculates the number of 1085 * strings to sort and then calls msort (short for merge sort) to do the 1086 * work. 1087 */ 1088 1089STATIC struct strlist * 1090expsort(str) 1091 struct strlist *str; 1092 { 1093 int len; 1094 struct strlist *sp; 1095 1096 len = 0; 1097 for (sp = str ; sp ; sp = sp->next) 1098 len++; 1099 return msort(str, len); 1100} 1101 1102 1103STATIC struct strlist * 1104msort(list, len) 1105 struct strlist *list; 1106 int len; 1107{ 1108 struct strlist *p, *q = NULL; 1109 struct strlist **lpp; 1110 int half; 1111 int n; 1112 1113 if (len <= 1) 1114 return list; 1115 half = len >> 1; 1116 p = list; 1117 for (n = half ; --n >= 0 ; ) { 1118 q = p; 1119 p = p->next; 1120 } 1121 q->next = NULL; /* terminate first half of list */ 1122 q = msort(list, half); /* sort first half of list */ 1123 p = msort(p, len - half); /* sort second half */ 1124 lpp = &list; 1125 for (;;) { 1126 if (strcmp(p->text, q->text) < 0) { 1127 *lpp = p; 1128 lpp = &p->next; 1129 if ((p = *lpp) == NULL) { 1130 *lpp = q; 1131 break; 1132 } 1133 } else { 1134 *lpp = q; 1135 lpp = &q->next; 1136 if ((q = *lpp) == NULL) { 1137 *lpp = p; 1138 break; 1139 } 1140 } 1141 } 1142 return list; 1143} 1144 1145 1146 1147/* 1148 * Returns true if the pattern matches the string. 1149 */ 1150 1151int 1152patmatch(pattern, string) 1153 char *pattern; 1154 char *string; 1155 { 1156#ifdef notdef 1157 if (pattern[0] == '!' && pattern[1] == '!') 1158 return 1 - pmatch(pattern + 2, string); 1159 else 1160#endif 1161 return pmatch(pattern, string); 1162} 1163 1164 1165STATIC int 1166pmatch(pattern, string) 1167 char *pattern; 1168 char *string; 1169 { 1170 register char *p, *q; 1171 register char c; 1172 1173 p = pattern; 1174 q = string; 1175 for (;;) { 1176 switch (c = *p++) { 1177 case '\0': 1178 goto breakloop; 1179 case CTLESC: 1180 if (*q++ != *p++) 1181 return 0; 1182 break; 1183 case '?': 1184 if (*q++ == '\0') 1185 return 0; 1186 break; 1187 case '*': 1188 c = *p; 1189 if (c != CTLESC && c != '?' && c != '*' && c != '[') { 1190 while (*q != c) { 1191 if (*q == '\0') 1192 return 0; 1193 q++; 1194 } 1195 } 1196 do { 1197 if (pmatch(p, q)) 1198 return 1; 1199 } while (*q++ != '\0'); 1200 return 0; 1201 case '[': { 1202 char *endp; 1203 int invert, found; 1204 char chr; 1205 1206 endp = p; 1207 if (*endp == '!') 1208 endp++; 1209 for (;;) { 1210 if (*endp == '\0') 1211 goto dft; /* no matching ] */ 1212 if (*endp == CTLESC) 1213 endp++; 1214 if (*++endp == ']') 1215 break; 1216 } 1217 invert = 0; 1218 if (*p == '!') { 1219 invert++; 1220 p++; 1221 } 1222 found = 0; 1223 chr = *q++; 1224 if (chr == '\0') 1225 return 0; 1226 c = *p++; 1227 do { 1228 if (c == CTLESC) 1229 c = *p++; 1230 if (*p == '-' && p[1] != ']') { 1231 p++; 1232 if (*p == CTLESC) 1233 p++; 1234 if ( collate_range_cmp(chr, c) >= 0 1235 && collate_range_cmp(chr, *p) <= 0 1236 ) 1237 found = 1; 1238 p++; 1239 } else { 1240 if (chr == c) 1241 found = 1; 1242 } 1243 } while ((c = *p++) != ']'); 1244 if (found == invert) 1245 return 0; 1246 break; 1247 } 1248dft: default: 1249 if (*q++ != c) 1250 return 0; 1251 break; 1252 } 1253 } 1254breakloop: 1255 if (*q != '\0') 1256 return 0; 1257 return 1; 1258} 1259 1260 1261 1262/* 1263 * Remove any CTLESC characters from a string. 1264 */ 1265 1266void 1267rmescapes(str) 1268 char *str; 1269 { 1270 register char *p, *q; 1271 1272 p = str; 1273 while (*p != CTLESC) { 1274 if (*p++ == '\0') 1275 return; 1276 } 1277 q = p; 1278 while (*p) { 1279 if (*p == CTLESC) 1280 p++; 1281 *q++ = *p++; 1282 } 1283 *q = '\0'; 1284} 1285 1286 1287 1288/* 1289 * See if a pattern matches in a case statement. 1290 */ 1291 1292int 1293casematch(pattern, val) 1294 union node *pattern; 1295 char *val; 1296 { 1297 struct stackmark smark; 1298 int result; 1299 char *p; 1300 1301 setstackmark(&smark); 1302 argbackq = pattern->narg.backquote; 1303 STARTSTACKSTR(expdest); 1304 ifslastp = NULL; 1305 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); 1306 STPUTC('\0', expdest); 1307 p = grabstackstr(expdest); 1308 result = patmatch(p, val); 1309 popstackmark(&smark); 1310 return result; 1311} 1312 1313/* 1314 * Our own itoa(). 1315 */ 1316 1317STATIC char * 1318cvtnum(num, buf) 1319 int num; 1320 char *buf; 1321 { 1322 char temp[32]; 1323 int neg = num < 0; 1324 char *p = temp + 31; 1325 1326 temp[31] = '\0'; 1327 1328 do { 1329 *--p = num % 10 + '0'; 1330 } while ((num /= 10) != 0); 1331 1332 if (neg) 1333 *--p = '-'; 1334 1335 while (*p) 1336 STPUTC(*p++, buf); 1337 return buf; 1338} 1339