1 /*- 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * Copyright (c) 1997-2005 5 * Herbert Xu <herbert@gondor.apana.org.au>. 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 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #ifndef lint 36 #if 0 37 static char sccsid[] = "@(#)expand.c 8.5 (Berkeley) 5/15/95"; 38 #endif 39 #endif /* not lint */ 40 #include <sys/cdefs.h> 41 __FBSDID("$FreeBSD$"); 42 43 #include <sys/types.h> 44 #include <sys/time.h> 45 #include <sys/stat.h> 46 #include <dirent.h> 47 #include <errno.h> 48 #include <inttypes.h> 49 #include <limits.h> 50 #include <pwd.h> 51 #include <stdio.h> 52 #include <stdlib.h> 53 #include <string.h> 54 #include <unistd.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 inquotes; /* search for nul bytes only */ 89 }; 90 91 92 static char *expdest; /* output of current string */ 93 static struct nodelist *argbackq; /* list of back quote expressions */ 94 static struct ifsregion ifsfirst; /* first struct in list of ifs regions */ 95 static struct ifsregion *ifslastp; /* last struct in list */ 96 static struct arglist exparg; /* holds expanded arg list */ 97 98 static void argstr(char *, int); 99 static char *exptilde(char *, int); 100 static void expbackq(union node *, int, int); 101 static int subevalvar(char *, char *, int, int, int, int, int); 102 static char *evalvar(char *, int); 103 static int varisset(char *, int); 104 static void varvalue(char *, int, int, int); 105 static void recordregion(int, int, int); 106 static void removerecordregions(int); 107 static void ifsbreakup(char *, struct arglist *); 108 static void expandmeta(struct strlist *, int); 109 static void expmeta(char *, char *); 110 static void addfname(char *); 111 static struct strlist *expsort(struct strlist *); 112 static struct strlist *msort(struct strlist *, int); 113 static char *cvtnum(int, char *); 114 static int collate_range_cmp(int, int); 115 116 static int 117 collate_range_cmp(int c1, int c2) 118 { 119 static char s1[2], s2[2]; 120 121 s1[0] = c1; 122 s2[0] = c2; 123 return (strcoll(s1, s2)); 124 } 125 126 /* 127 * Expand shell variables and backquotes inside a here document. 128 * union node *arg the document 129 * int fd; where to write the expanded version 130 */ 131 132 void 133 expandhere(union node *arg, int fd) 134 { 135 herefd = fd; 136 expandarg(arg, (struct arglist *)NULL, 0); 137 xwrite(fd, stackblock(), expdest - stackblock()); 138 } 139 140 141 /* 142 * Perform expansions on an argument, placing the resulting list of arguments 143 * in arglist. Parameter expansion, command substitution and arithmetic 144 * expansion are always performed; additional expansions can be requested 145 * via flag (EXP_*). 146 * The result is left in the stack string. 147 * When arglist is NULL, perform here document expansion. A partial result 148 * may be written to herefd, which is then not included in the stack string. 149 * 150 * Caution: this function uses global state and is not reentrant. 151 * However, a new invocation after an interrupted invocation is safe 152 * and will reset the global state for the new call. 153 */ 154 void 155 expandarg(union node *arg, struct arglist *arglist, int flag) 156 { 157 struct strlist *sp; 158 char *p; 159 160 argbackq = arg->narg.backquote; 161 STARTSTACKSTR(expdest); 162 ifsfirst.next = NULL; 163 ifslastp = NULL; 164 argstr(arg->narg.text, flag); 165 if (arglist == NULL) { 166 return; /* here document expanded */ 167 } 168 STPUTC('\0', expdest); 169 p = grabstackstr(expdest); 170 exparg.lastp = &exparg.list; 171 /* 172 * TODO - EXP_REDIR 173 */ 174 if (flag & EXP_FULL) { 175 ifsbreakup(p, &exparg); 176 *exparg.lastp = NULL; 177 exparg.lastp = &exparg.list; 178 expandmeta(exparg.list, flag); 179 } else { 180 if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */ 181 rmescapes(p); 182 sp = (struct strlist *)stalloc(sizeof (struct strlist)); 183 sp->text = p; 184 *exparg.lastp = sp; 185 exparg.lastp = &sp->next; 186 } 187 while (ifsfirst.next != NULL) { 188 struct ifsregion *ifsp; 189 INTOFF; 190 ifsp = ifsfirst.next->next; 191 ckfree(ifsfirst.next); 192 ifsfirst.next = ifsp; 193 INTON; 194 } 195 *exparg.lastp = NULL; 196 if (exparg.list) { 197 *arglist->lastp = exparg.list; 198 arglist->lastp = exparg.lastp; 199 } 200 } 201 202 203 204 /* 205 * Perform parameter expansion, command substitution and arithmetic 206 * expansion, and tilde expansion if requested via EXP_TILDE/EXP_VARTILDE. 207 * Processing ends at a CTLENDVAR character as well as '\0'. 208 * This is used to expand word in ${var+word} etc. 209 * If EXP_FULL, EXP_CASE or EXP_REDIR are set, keep and/or generate CTLESC 210 * characters to allow for further processing. 211 * If EXP_FULL is set, also preserve CTLQUOTEMARK characters. 212 */ 213 static void 214 argstr(char *p, int flag) 215 { 216 char c; 217 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); /* do CTLESC */ 218 int firsteq = 1; 219 int split_lit; 220 int lit_quoted; 221 222 split_lit = flag & EXP_SPLIT_LIT; 223 lit_quoted = flag & EXP_LIT_QUOTED; 224 flag &= ~(EXP_SPLIT_LIT | EXP_LIT_QUOTED); 225 if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE))) 226 p = exptilde(p, flag); 227 for (;;) { 228 CHECKSTRSPACE(2, expdest); 229 switch (c = *p++) { 230 case '\0': 231 case CTLENDVAR: 232 goto breakloop; 233 case CTLQUOTEMARK: 234 lit_quoted = 1; 235 /* "$@" syntax adherence hack */ 236 if (p[0] == CTLVAR && p[2] == '@' && p[3] == '=') 237 break; 238 if ((flag & EXP_FULL) != 0) 239 USTPUTC(c, expdest); 240 break; 241 case CTLQUOTEEND: 242 lit_quoted = 0; 243 break; 244 case CTLESC: 245 if (quotes) 246 USTPUTC(c, expdest); 247 c = *p++; 248 USTPUTC(c, expdest); 249 if (split_lit && !lit_quoted) 250 recordregion(expdest - stackblock() - 251 (quotes ? 2 : 1), 252 expdest - stackblock(), 0); 253 break; 254 case CTLVAR: 255 p = evalvar(p, flag); 256 break; 257 case CTLBACKQ: 258 case CTLBACKQ|CTLQUOTE: 259 expbackq(argbackq->n, c & CTLQUOTE, flag); 260 argbackq = argbackq->next; 261 break; 262 case CTLENDARI: 263 expari(flag); 264 break; 265 case ':': 266 case '=': 267 /* 268 * sort of a hack - expand tildes in variable 269 * assignments (after the first '=' and after ':'s). 270 */ 271 USTPUTC(c, expdest); 272 if (split_lit && !lit_quoted) 273 recordregion(expdest - stackblock() - 1, 274 expdest - stackblock(), 0); 275 if (flag & EXP_VARTILDE && *p == '~' && 276 (c != '=' || firsteq)) { 277 if (c == '=') 278 firsteq = 0; 279 p = exptilde(p, flag); 280 } 281 break; 282 default: 283 USTPUTC(c, expdest); 284 if (split_lit && !lit_quoted) 285 recordregion(expdest - stackblock() - 1, 286 expdest - stackblock(), 0); 287 } 288 } 289 breakloop:; 290 } 291 292 /* 293 * Perform tilde expansion, placing the result in the stack string and 294 * returning the next position in the input string to process. 295 */ 296 static char * 297 exptilde(char *p, int flag) 298 { 299 char c, *startp = p; 300 struct passwd *pw; 301 char *home; 302 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 303 304 while ((c = *p) != '\0') { 305 switch(c) { 306 case CTLESC: /* This means CTL* are always considered quoted. */ 307 case CTLVAR: 308 case CTLBACKQ: 309 case CTLBACKQ | CTLQUOTE: 310 case CTLARI: 311 case CTLENDARI: 312 case CTLQUOTEMARK: 313 return (startp); 314 case ':': 315 if (flag & EXP_VARTILDE) 316 goto done; 317 break; 318 case '/': 319 case CTLENDVAR: 320 goto done; 321 } 322 p++; 323 } 324 done: 325 *p = '\0'; 326 if (*(startp+1) == '\0') { 327 if ((home = lookupvar("HOME")) == NULL) 328 goto lose; 329 } else { 330 if ((pw = getpwnam(startp+1)) == NULL) 331 goto lose; 332 home = pw->pw_dir; 333 } 334 if (*home == '\0') 335 goto lose; 336 *p = c; 337 while ((c = *home++) != '\0') { 338 if (quotes && SQSYNTAX[(int)c] == CCTL) 339 STPUTC(CTLESC, expdest); 340 STPUTC(c, expdest); 341 } 342 return (p); 343 lose: 344 *p = c; 345 return (startp); 346 } 347 348 349 static void 350 removerecordregions(int endoff) 351 { 352 if (ifslastp == NULL) 353 return; 354 355 if (ifsfirst.endoff > endoff) { 356 while (ifsfirst.next != NULL) { 357 struct ifsregion *ifsp; 358 INTOFF; 359 ifsp = ifsfirst.next->next; 360 ckfree(ifsfirst.next); 361 ifsfirst.next = ifsp; 362 INTON; 363 } 364 if (ifsfirst.begoff > endoff) 365 ifslastp = NULL; 366 else { 367 ifslastp = &ifsfirst; 368 ifsfirst.endoff = endoff; 369 } 370 return; 371 } 372 373 ifslastp = &ifsfirst; 374 while (ifslastp->next && ifslastp->next->begoff < endoff) 375 ifslastp=ifslastp->next; 376 while (ifslastp->next != NULL) { 377 struct ifsregion *ifsp; 378 INTOFF; 379 ifsp = ifslastp->next->next; 380 ckfree(ifslastp->next); 381 ifslastp->next = ifsp; 382 INTON; 383 } 384 if (ifslastp->endoff > endoff) 385 ifslastp->endoff = endoff; 386 } 387 388 /* 389 * Expand arithmetic expression. Backup to start of expression, 390 * evaluate, place result in (backed up) result, adjust string position. 391 */ 392 void 393 expari(int flag) 394 { 395 char *p, *q, *start; 396 arith_t result; 397 int begoff; 398 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 399 int quoted; 400 401 /* 402 * This routine is slightly over-complicated for 403 * efficiency. First we make sure there is 404 * enough space for the result, which may be bigger 405 * than the expression. Next we 406 * scan backwards looking for the start of arithmetic. If the 407 * next previous character is a CTLESC character, then we 408 * have to rescan starting from the beginning since CTLESC 409 * characters have to be processed left to right. 410 */ 411 CHECKSTRSPACE(DIGITS(result) - 2, expdest); 412 USTPUTC('\0', expdest); 413 start = stackblock(); 414 p = expdest - 2; 415 while (p >= start && *p != CTLARI) 416 --p; 417 if (p < start || *p != CTLARI) 418 error("missing CTLARI (shouldn't happen)"); 419 if (p > start && *(p - 1) == CTLESC) 420 for (p = start; *p != CTLARI; p++) 421 if (*p == CTLESC) 422 p++; 423 424 if (p[1] == '"') 425 quoted=1; 426 else 427 quoted=0; 428 begoff = p - start; 429 removerecordregions(begoff); 430 if (quotes) 431 rmescapes(p+2); 432 q = grabstackstr(expdest); 433 result = arith(p+2); 434 ungrabstackstr(q, expdest); 435 fmtstr(p, DIGITS(result), ARITH_FORMAT_STR, result); 436 while (*p++) 437 ; 438 if (quoted == 0) 439 recordregion(begoff, p - 1 - start, 0); 440 result = expdest - p + 1; 441 STADJUST(-result, expdest); 442 } 443 444 445 /* 446 * Perform command substitution. 447 */ 448 static void 449 expbackq(union node *cmd, int quoted, int flag) 450 { 451 struct backcmd in; 452 int i; 453 char buf[128]; 454 char *p; 455 char *dest = expdest; 456 struct ifsregion saveifs, *savelastp; 457 struct nodelist *saveargbackq; 458 char lastc; 459 int startloc = dest - stackblock(); 460 char const *syntax = quoted? DQSYNTAX : BASESYNTAX; 461 int saveherefd; 462 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 463 int nnl; 464 465 INTOFF; 466 saveifs = ifsfirst; 467 savelastp = ifslastp; 468 saveargbackq = argbackq; 469 saveherefd = herefd; 470 herefd = -1; 471 p = grabstackstr(dest); 472 evalbackcmd(cmd, &in); 473 ungrabstackstr(p, dest); 474 ifsfirst = saveifs; 475 ifslastp = savelastp; 476 argbackq = saveargbackq; 477 herefd = saveherefd; 478 479 p = in.buf; 480 lastc = '\0'; 481 nnl = 0; 482 /* Don't copy trailing newlines */ 483 for (;;) { 484 if (--in.nleft < 0) { 485 if (in.fd < 0) 486 break; 487 while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR); 488 TRACE(("expbackq: read returns %d\n", i)); 489 if (i <= 0) 490 break; 491 p = buf; 492 in.nleft = i - 1; 493 } 494 lastc = *p++; 495 if (lastc != '\0') { 496 if (quotes && syntax[(int)lastc] == CCTL) 497 STPUTC(CTLESC, dest); 498 if (lastc == '\n') { 499 nnl++; 500 } else { 501 while (nnl > 0) { 502 nnl--; 503 STPUTC('\n', dest); 504 } 505 STPUTC(lastc, dest); 506 } 507 } 508 } 509 510 if (in.fd >= 0) 511 close(in.fd); 512 if (in.buf) 513 ckfree(in.buf); 514 if (in.jp) 515 exitstatus = waitforjob(in.jp, (int *)NULL); 516 if (quoted == 0) 517 recordregion(startloc, dest - stackblock(), 0); 518 TRACE(("expbackq: size=%td: \"%.*s\"\n", 519 ((dest - stackblock()) - startloc), 520 (int)((dest - stackblock()) - startloc), 521 stackblock() + startloc)); 522 expdest = dest; 523 INTON; 524 } 525 526 527 528 static int 529 subevalvar(char *p, char *str, int strloc, int subtype, int startloc, 530 int varflags, int quotes) 531 { 532 char *startp; 533 char *loc = NULL; 534 char *q; 535 int c = 0; 536 int saveherefd = herefd; 537 struct nodelist *saveargbackq = argbackq; 538 int amount; 539 540 herefd = -1; 541 argstr(p, (subtype == VSTRIMLEFT || subtype == VSTRIMLEFTMAX || 542 subtype == VSTRIMRIGHT || subtype == VSTRIMRIGHTMAX ? 543 EXP_CASE : 0) | EXP_TILDE); 544 STACKSTRNUL(expdest); 545 herefd = saveherefd; 546 argbackq = saveargbackq; 547 startp = stackblock() + startloc; 548 if (str == NULL) 549 str = stackblock() + strloc; 550 551 switch (subtype) { 552 case VSASSIGN: 553 setvar(str, startp, 0); 554 amount = startp - expdest; 555 STADJUST(amount, expdest); 556 varflags &= ~VSNUL; 557 if (c != 0) 558 *loc = c; 559 return 1; 560 561 case VSQUESTION: 562 if (*p != CTLENDVAR) { 563 outfmt(out2, "%s\n", startp); 564 error((char *)NULL); 565 } 566 error("%.*s: parameter %snot set", (int)(p - str - 1), 567 str, (varflags & VSNUL) ? "null or " 568 : nullstr); 569 return 0; 570 571 case VSTRIMLEFT: 572 for (loc = startp; loc < str; loc++) { 573 c = *loc; 574 *loc = '\0'; 575 if (patmatch(str, startp, quotes)) { 576 *loc = c; 577 goto recordleft; 578 } 579 *loc = c; 580 if (quotes && *loc == CTLESC) 581 loc++; 582 } 583 return 0; 584 585 case VSTRIMLEFTMAX: 586 for (loc = str - 1; loc >= startp;) { 587 c = *loc; 588 *loc = '\0'; 589 if (patmatch(str, startp, quotes)) { 590 *loc = c; 591 goto recordleft; 592 } 593 *loc = c; 594 loc--; 595 if (quotes && loc > startp && *(loc - 1) == CTLESC) { 596 for (q = startp; q < loc; q++) 597 if (*q == CTLESC) 598 q++; 599 if (q > loc) 600 loc--; 601 } 602 } 603 return 0; 604 605 case VSTRIMRIGHT: 606 for (loc = str - 1; loc >= startp;) { 607 if (patmatch(str, loc, quotes)) { 608 amount = loc - expdest; 609 STADJUST(amount, expdest); 610 return 1; 611 } 612 loc--; 613 if (quotes && loc > startp && *(loc - 1) == CTLESC) { 614 for (q = startp; q < loc; q++) 615 if (*q == CTLESC) 616 q++; 617 if (q > loc) 618 loc--; 619 } 620 } 621 return 0; 622 623 case VSTRIMRIGHTMAX: 624 for (loc = startp; loc < str - 1; loc++) { 625 if (patmatch(str, loc, quotes)) { 626 amount = loc - expdest; 627 STADJUST(amount, expdest); 628 return 1; 629 } 630 if (quotes && *loc == CTLESC) 631 loc++; 632 } 633 return 0; 634 635 636 default: 637 abort(); 638 } 639 640 recordleft: 641 amount = ((str - 1) - (loc - startp)) - expdest; 642 STADJUST(amount, expdest); 643 while (loc != str - 1) 644 *startp++ = *loc++; 645 return 1; 646 } 647 648 649 /* 650 * Expand a variable, and return a pointer to the next character in the 651 * input string. 652 */ 653 654 static char * 655 evalvar(char *p, int flag) 656 { 657 int subtype; 658 int varflags; 659 char *var; 660 char *val; 661 int patloc; 662 int c; 663 int set; 664 int special; 665 int startloc; 666 int varlen; 667 int easy; 668 int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR); 669 670 varflags = (unsigned char)*p++; 671 subtype = varflags & VSTYPE; 672 var = p; 673 special = 0; 674 if (! is_name(*p)) 675 special = 1; 676 p = strchr(p, '=') + 1; 677 again: /* jump here after setting a variable with ${var=text} */ 678 if (varflags & VSLINENO) { 679 set = 1; 680 special = 0; 681 val = var; 682 p[-1] = '\0'; /* temporarily overwrite '=' to have \0 683 terminated string */ 684 } else if (special) { 685 set = varisset(var, varflags & VSNUL); 686 val = NULL; 687 } else { 688 val = bltinlookup(var, 1); 689 if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) { 690 val = NULL; 691 set = 0; 692 } else 693 set = 1; 694 } 695 varlen = 0; 696 startloc = expdest - stackblock(); 697 if (!set && uflag && *var != '@' && *var != '*') { 698 switch (subtype) { 699 case VSNORMAL: 700 case VSTRIMLEFT: 701 case VSTRIMLEFTMAX: 702 case VSTRIMRIGHT: 703 case VSTRIMRIGHTMAX: 704 case VSLENGTH: 705 error("%.*s: parameter not set", (int)(p - var - 1), 706 var); 707 } 708 } 709 if (set && subtype != VSPLUS) { 710 /* insert the value of the variable */ 711 if (special) { 712 varvalue(var, varflags & VSQUOTE, subtype, flag); 713 if (subtype == VSLENGTH) { 714 varlen = expdest - stackblock() - startloc; 715 STADJUST(-varlen, expdest); 716 } 717 } else { 718 char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX 719 : BASESYNTAX; 720 721 if (subtype == VSLENGTH) { 722 for (;*val; val++) 723 varlen++; 724 } 725 else { 726 while (*val) { 727 if (quotes && 728 syntax[(int)*val] == CCTL) 729 STPUTC(CTLESC, expdest); 730 STPUTC(*val++, expdest); 731 } 732 733 } 734 } 735 } 736 737 if (subtype == VSPLUS) 738 set = ! set; 739 740 easy = ((varflags & VSQUOTE) == 0 || 741 (*var == '@' && shellparam.nparam != 1)); 742 743 744 switch (subtype) { 745 case VSLENGTH: 746 expdest = cvtnum(varlen, expdest); 747 goto record; 748 749 case VSNORMAL: 750 if (!easy) 751 break; 752 record: 753 recordregion(startloc, expdest - stackblock(), 754 varflags & VSQUOTE); 755 break; 756 757 case VSPLUS: 758 case VSMINUS: 759 if (!set) { 760 argstr(p, flag | (flag & EXP_FULL ? EXP_SPLIT_LIT : 0) | 761 (varflags & VSQUOTE ? EXP_LIT_QUOTED : 0)); 762 break; 763 } 764 if (easy) 765 goto record; 766 break; 767 768 case VSTRIMLEFT: 769 case VSTRIMLEFTMAX: 770 case VSTRIMRIGHT: 771 case VSTRIMRIGHTMAX: 772 if (!set) 773 break; 774 /* 775 * Terminate the string and start recording the pattern 776 * right after it 777 */ 778 STPUTC('\0', expdest); 779 patloc = expdest - stackblock(); 780 if (subevalvar(p, NULL, patloc, subtype, 781 startloc, varflags, quotes) == 0) { 782 int amount = (expdest - stackblock() - patloc) + 1; 783 STADJUST(-amount, expdest); 784 } 785 /* Remove any recorded regions beyond start of variable */ 786 removerecordregions(startloc); 787 goto record; 788 789 case VSASSIGN: 790 case VSQUESTION: 791 if (!set) { 792 if (subevalvar(p, var, 0, subtype, startloc, varflags, 793 quotes)) { 794 varflags &= ~VSNUL; 795 /* 796 * Remove any recorded regions beyond 797 * start of variable 798 */ 799 removerecordregions(startloc); 800 goto again; 801 } 802 break; 803 } 804 if (easy) 805 goto record; 806 break; 807 808 case VSERROR: 809 c = p - var - 1; 810 error("${%.*s%s}: Bad substitution", c, var, 811 (c > 0 && *p != CTLENDVAR) ? "..." : ""); 812 813 default: 814 abort(); 815 } 816 p[-1] = '='; /* recover overwritten '=' */ 817 818 if (subtype != VSNORMAL) { /* skip to end of alternative */ 819 int nesting = 1; 820 for (;;) { 821 if ((c = *p++) == CTLESC) 822 p++; 823 else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { 824 if (set) 825 argbackq = argbackq->next; 826 } else if (c == CTLVAR) { 827 if ((*p++ & VSTYPE) != VSNORMAL) 828 nesting++; 829 } else if (c == CTLENDVAR) { 830 if (--nesting == 0) 831 break; 832 } 833 } 834 } 835 return p; 836 } 837 838 839 840 /* 841 * Test whether a specialized variable is set. 842 */ 843 844 static int 845 varisset(char *name, int nulok) 846 { 847 848 if (*name == '!') 849 return backgndpidset(); 850 else if (*name == '@' || *name == '*') { 851 if (*shellparam.p == NULL) 852 return 0; 853 854 if (nulok) { 855 char **av; 856 857 for (av = shellparam.p; *av; av++) 858 if (**av != '\0') 859 return 1; 860 return 0; 861 } 862 } else if (is_digit(*name)) { 863 char *ap; 864 int num = atoi(name); 865 866 if (num > shellparam.nparam) 867 return 0; 868 869 if (num == 0) 870 ap = arg0; 871 else 872 ap = shellparam.p[num - 1]; 873 874 if (nulok && (ap == NULL || *ap == '\0')) 875 return 0; 876 } 877 return 1; 878 } 879 880 881 882 /* 883 * Add the value of a specialized variable to the stack string. 884 */ 885 886 static void 887 varvalue(char *name, int quoted, int subtype, int flag) 888 { 889 int num; 890 char *p; 891 int i; 892 char sep; 893 char **ap; 894 char const *syntax; 895 896 #define STRTODEST(p) \ 897 do {\ 898 if (flag & (EXP_FULL | EXP_CASE) && subtype != VSLENGTH) { \ 899 syntax = quoted? DQSYNTAX : BASESYNTAX; \ 900 while (*p) { \ 901 if (syntax[(int)*p] == CCTL) \ 902 STPUTC(CTLESC, expdest); \ 903 STPUTC(*p++, expdest); \ 904 } \ 905 } else \ 906 STPUTS(p, expdest); \ 907 } while (0) 908 909 910 switch (*name) { 911 case '$': 912 num = rootpid; 913 goto numvar; 914 case '?': 915 num = oexitstatus; 916 goto numvar; 917 case '#': 918 num = shellparam.nparam; 919 goto numvar; 920 case '!': 921 num = backgndpidval(); 922 numvar: 923 expdest = cvtnum(num, expdest); 924 break; 925 case '-': 926 for (i = 0 ; i < NOPTS ; i++) { 927 if (optlist[i].val) 928 STPUTC(optlist[i].letter, expdest); 929 } 930 break; 931 case '@': 932 if (flag & EXP_FULL && quoted) { 933 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 934 STRTODEST(p); 935 if (*ap) 936 STPUTC('\0', expdest); 937 } 938 break; 939 } 940 /* FALLTHROUGH */ 941 case '*': 942 if (ifsset()) 943 sep = ifsval()[0]; 944 else 945 sep = ' '; 946 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) { 947 STRTODEST(p); 948 if (*ap && sep) 949 STPUTC(sep, expdest); 950 } 951 break; 952 case '0': 953 p = arg0; 954 STRTODEST(p); 955 break; 956 default: 957 if (is_digit(*name)) { 958 num = atoi(name); 959 if (num > 0 && num <= shellparam.nparam) { 960 p = shellparam.p[num - 1]; 961 STRTODEST(p); 962 } 963 } 964 break; 965 } 966 } 967 968 969 970 /* 971 * Record the the fact that we have to scan this region of the 972 * string for IFS characters. 973 */ 974 975 static void 976 recordregion(int start, int end, int inquotes) 977 { 978 struct ifsregion *ifsp; 979 980 if (ifslastp == NULL) { 981 ifsp = &ifsfirst; 982 } else { 983 if (ifslastp->endoff == start 984 && ifslastp->inquotes == inquotes) { 985 /* extend previous area */ 986 ifslastp->endoff = end; 987 return; 988 } 989 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion)); 990 ifslastp->next = ifsp; 991 } 992 ifslastp = ifsp; 993 ifslastp->next = NULL; 994 ifslastp->begoff = start; 995 ifslastp->endoff = end; 996 ifslastp->inquotes = inquotes; 997 } 998 999 1000 1001 /* 1002 * Break the argument string into pieces based upon IFS and add the 1003 * strings to the argument list. The regions of the string to be 1004 * searched for IFS characters have been stored by recordregion. 1005 * CTLESC characters are preserved but have little effect in this pass 1006 * other than escaping CTL* characters. In particular, they do not escape 1007 * IFS characters: that should be done with the ifsregion mechanism. 1008 * CTLQUOTEMARK characters are used to preserve empty quoted strings. 1009 * This pass treats them as a regular character, making the string non-empty. 1010 * Later, they are removed along with the other CTL* characters. 1011 */ 1012 static void 1013 ifsbreakup(char *string, struct arglist *arglist) 1014 { 1015 struct ifsregion *ifsp; 1016 struct strlist *sp; 1017 char *start; 1018 char *p; 1019 char *q; 1020 const char *ifs; 1021 const char *ifsspc; 1022 int had_param_ch = 0; 1023 1024 start = string; 1025 1026 if (ifslastp == NULL) { 1027 /* Return entire argument, IFS doesn't apply to any of it */ 1028 sp = (struct strlist *)stalloc(sizeof *sp); 1029 sp->text = start; 1030 *arglist->lastp = sp; 1031 arglist->lastp = &sp->next; 1032 return; 1033 } 1034 1035 ifs = ifsset() ? ifsval() : " \t\n"; 1036 1037 for (ifsp = &ifsfirst; ifsp != NULL; ifsp = ifsp->next) { 1038 p = string + ifsp->begoff; 1039 while (p < string + ifsp->endoff) { 1040 q = p; 1041 if (*p == CTLESC) 1042 p++; 1043 if (ifsp->inquotes) { 1044 /* Only NULs (should be from "$@") end args */ 1045 had_param_ch = 1; 1046 if (*p != 0) { 1047 p++; 1048 continue; 1049 } 1050 ifsspc = NULL; 1051 } else { 1052 if (!strchr(ifs, *p)) { 1053 had_param_ch = 1; 1054 p++; 1055 continue; 1056 } 1057 ifsspc = strchr(" \t\n", *p); 1058 1059 /* Ignore IFS whitespace at start */ 1060 if (q == start && ifsspc != NULL) { 1061 p++; 1062 start = p; 1063 continue; 1064 } 1065 had_param_ch = 0; 1066 } 1067 1068 /* Save this argument... */ 1069 *q = '\0'; 1070 sp = (struct strlist *)stalloc(sizeof *sp); 1071 sp->text = start; 1072 *arglist->lastp = sp; 1073 arglist->lastp = &sp->next; 1074 p++; 1075 1076 if (ifsspc != NULL) { 1077 /* Ignore further trailing IFS whitespace */ 1078 for (; p < string + ifsp->endoff; p++) { 1079 q = p; 1080 if (*p == CTLESC) 1081 p++; 1082 if (strchr(ifs, *p) == NULL) { 1083 p = q; 1084 break; 1085 } 1086 if (strchr(" \t\n", *p) == NULL) { 1087 p++; 1088 break; 1089 } 1090 } 1091 } 1092 start = p; 1093 } 1094 } 1095 1096 /* 1097 * Save anything left as an argument. 1098 * Traditionally we have treated 'IFS=':'; set -- x$IFS' as 1099 * generating 2 arguments, the second of which is empty. 1100 * Some recent clarification of the Posix spec say that it 1101 * should only generate one.... 1102 */ 1103 if (had_param_ch || *start != 0) { 1104 sp = (struct strlist *)stalloc(sizeof *sp); 1105 sp->text = start; 1106 *arglist->lastp = sp; 1107 arglist->lastp = &sp->next; 1108 } 1109 } 1110 1111 1112 static char expdir[PATH_MAX]; 1113 #define expdir_end (expdir + sizeof(expdir)) 1114 1115 /* 1116 * Perform pathname generation and remove control characters. 1117 * At this point, the only control characters should be CTLESC and CTLQUOTEMARK. 1118 * The results are stored in the list exparg. 1119 */ 1120 static void 1121 expandmeta(struct strlist *str, int flag __unused) 1122 { 1123 char *p; 1124 struct strlist **savelastp; 1125 struct strlist *sp; 1126 char c; 1127 /* TODO - EXP_REDIR */ 1128 1129 while (str) { 1130 if (fflag) 1131 goto nometa; 1132 p = str->text; 1133 for (;;) { /* fast check for meta chars */ 1134 if ((c = *p++) == '\0') 1135 goto nometa; 1136 if (c == '*' || c == '?' || c == '[') 1137 break; 1138 } 1139 savelastp = exparg.lastp; 1140 INTOFF; 1141 expmeta(expdir, str->text); 1142 INTON; 1143 if (exparg.lastp == savelastp) { 1144 /* 1145 * no matches 1146 */ 1147 nometa: 1148 *exparg.lastp = str; 1149 rmescapes(str->text); 1150 exparg.lastp = &str->next; 1151 } else { 1152 *exparg.lastp = NULL; 1153 *savelastp = sp = expsort(*savelastp); 1154 while (sp->next != NULL) 1155 sp = sp->next; 1156 exparg.lastp = &sp->next; 1157 } 1158 str = str->next; 1159 } 1160 } 1161 1162 1163 /* 1164 * Do metacharacter (i.e. *, ?, [...]) expansion. 1165 */ 1166 1167 static void 1168 expmeta(char *enddir, char *name) 1169 { 1170 char *p; 1171 char *q; 1172 char *start; 1173 char *endname; 1174 int metaflag; 1175 struct stat statb; 1176 DIR *dirp; 1177 struct dirent *dp; 1178 int atend; 1179 int matchdot; 1180 int esc; 1181 1182 metaflag = 0; 1183 start = name; 1184 for (p = name; esc = 0, *p; p += esc + 1) { 1185 if (*p == '*' || *p == '?') 1186 metaflag = 1; 1187 else if (*p == '[') { 1188 q = p + 1; 1189 if (*q == '!' || *q == '^') 1190 q++; 1191 for (;;) { 1192 while (*q == CTLQUOTEMARK) 1193 q++; 1194 if (*q == CTLESC) 1195 q++; 1196 if (*q == '/' || *q == '\0') 1197 break; 1198 if (*++q == ']') { 1199 metaflag = 1; 1200 break; 1201 } 1202 } 1203 } else if (*p == '\0') 1204 break; 1205 else if (*p == CTLQUOTEMARK) 1206 continue; 1207 else { 1208 if (*p == CTLESC) 1209 esc++; 1210 if (p[esc] == '/') { 1211 if (metaflag) 1212 break; 1213 start = p + esc + 1; 1214 } 1215 } 1216 } 1217 if (metaflag == 0) { /* we've reached the end of the file name */ 1218 if (enddir != expdir) 1219 metaflag++; 1220 for (p = name ; ; p++) { 1221 if (*p == CTLQUOTEMARK) 1222 continue; 1223 if (*p == CTLESC) 1224 p++; 1225 *enddir++ = *p; 1226 if (*p == '\0') 1227 break; 1228 if (enddir == expdir_end) 1229 return; 1230 } 1231 if (metaflag == 0 || lstat(expdir, &statb) >= 0) 1232 addfname(expdir); 1233 return; 1234 } 1235 endname = p; 1236 if (start != name) { 1237 p = name; 1238 while (p < start) { 1239 while (*p == CTLQUOTEMARK) 1240 p++; 1241 if (*p == CTLESC) 1242 p++; 1243 *enddir++ = *p++; 1244 if (enddir == expdir_end) 1245 return; 1246 } 1247 } 1248 if (enddir == expdir) { 1249 p = "."; 1250 } else if (enddir == expdir + 1 && *expdir == '/') { 1251 p = "/"; 1252 } else { 1253 p = expdir; 1254 enddir[-1] = '\0'; 1255 } 1256 if ((dirp = opendir(p)) == NULL) 1257 return; 1258 if (enddir != expdir) 1259 enddir[-1] = '/'; 1260 if (*endname == 0) { 1261 atend = 1; 1262 } else { 1263 atend = 0; 1264 *endname = '\0'; 1265 endname += esc + 1; 1266 } 1267 matchdot = 0; 1268 p = start; 1269 while (*p == CTLQUOTEMARK) 1270 p++; 1271 if (*p == CTLESC) 1272 p++; 1273 if (*p == '.') 1274 matchdot++; 1275 while (! int_pending() && (dp = readdir(dirp)) != NULL) { 1276 if (dp->d_name[0] == '.' && ! matchdot) 1277 continue; 1278 if (patmatch(start, dp->d_name, 0)) { 1279 if (enddir + dp->d_namlen + 1 > expdir_end) 1280 continue; 1281 memcpy(enddir, dp->d_name, dp->d_namlen + 1); 1282 if (atend) 1283 addfname(expdir); 1284 else { 1285 if (enddir + dp->d_namlen + 2 > expdir_end) 1286 continue; 1287 enddir[dp->d_namlen] = '/'; 1288 enddir[dp->d_namlen + 1] = '\0'; 1289 expmeta(enddir + dp->d_namlen + 1, endname); 1290 } 1291 } 1292 } 1293 closedir(dirp); 1294 if (! atend) 1295 endname[-esc - 1] = esc ? CTLESC : '/'; 1296 } 1297 1298 1299 /* 1300 * Add a file name to the list. 1301 */ 1302 1303 static void 1304 addfname(char *name) 1305 { 1306 char *p; 1307 struct strlist *sp; 1308 1309 p = stalloc(strlen(name) + 1); 1310 scopy(name, p); 1311 sp = (struct strlist *)stalloc(sizeof *sp); 1312 sp->text = p; 1313 *exparg.lastp = sp; 1314 exparg.lastp = &sp->next; 1315 } 1316 1317 1318 /* 1319 * Sort the results of file name expansion. It calculates the number of 1320 * strings to sort and then calls msort (short for merge sort) to do the 1321 * work. 1322 */ 1323 1324 static struct strlist * 1325 expsort(struct strlist *str) 1326 { 1327 int len; 1328 struct strlist *sp; 1329 1330 len = 0; 1331 for (sp = str ; sp ; sp = sp->next) 1332 len++; 1333 return msort(str, len); 1334 } 1335 1336 1337 static struct strlist * 1338 msort(struct strlist *list, int len) 1339 { 1340 struct strlist *p, *q = NULL; 1341 struct strlist **lpp; 1342 int half; 1343 int n; 1344 1345 if (len <= 1) 1346 return list; 1347 half = len >> 1; 1348 p = list; 1349 for (n = half ; --n >= 0 ; ) { 1350 q = p; 1351 p = p->next; 1352 } 1353 q->next = NULL; /* terminate first half of list */ 1354 q = msort(list, half); /* sort first half of list */ 1355 p = msort(p, len - half); /* sort second half */ 1356 lpp = &list; 1357 for (;;) { 1358 if (strcmp(p->text, q->text) < 0) { 1359 *lpp = p; 1360 lpp = &p->next; 1361 if ((p = *lpp) == NULL) { 1362 *lpp = q; 1363 break; 1364 } 1365 } else { 1366 *lpp = q; 1367 lpp = &q->next; 1368 if ((q = *lpp) == NULL) { 1369 *lpp = p; 1370 break; 1371 } 1372 } 1373 } 1374 return list; 1375 } 1376 1377 1378 1379 /* 1380 * Returns true if the pattern matches the string. 1381 */ 1382 1383 int 1384 patmatch(const char *pattern, const char *string, int squoted) 1385 { 1386 const char *p, *q; 1387 char c; 1388 1389 p = pattern; 1390 q = string; 1391 for (;;) { 1392 switch (c = *p++) { 1393 case '\0': 1394 goto breakloop; 1395 case CTLESC: 1396 if (squoted && *q == CTLESC) 1397 q++; 1398 if (*q++ != *p++) 1399 return 0; 1400 break; 1401 case CTLQUOTEMARK: 1402 continue; 1403 case '?': 1404 if (squoted && *q == CTLESC) 1405 q++; 1406 if (*q++ == '\0') 1407 return 0; 1408 break; 1409 case '*': 1410 c = *p; 1411 while (c == CTLQUOTEMARK || c == '*') 1412 c = *++p; 1413 if (c != CTLESC && c != CTLQUOTEMARK && 1414 c != '?' && c != '*' && c != '[') { 1415 while (*q != c) { 1416 if (squoted && *q == CTLESC && 1417 q[1] == c) 1418 break; 1419 if (*q == '\0') 1420 return 0; 1421 if (squoted && *q == CTLESC) 1422 q++; 1423 q++; 1424 } 1425 } 1426 do { 1427 if (patmatch(p, q, squoted)) 1428 return 1; 1429 if (squoted && *q == CTLESC) 1430 q++; 1431 } while (*q++ != '\0'); 1432 return 0; 1433 case '[': { 1434 const char *endp; 1435 int invert, found; 1436 char chr; 1437 1438 endp = p; 1439 if (*endp == '!' || *endp == '^') 1440 endp++; 1441 for (;;) { 1442 while (*endp == CTLQUOTEMARK) 1443 endp++; 1444 if (*endp == '\0') 1445 goto dft; /* no matching ] */ 1446 if (*endp == CTLESC) 1447 endp++; 1448 if (*++endp == ']') 1449 break; 1450 } 1451 invert = 0; 1452 if (*p == '!' || *p == '^') { 1453 invert++; 1454 p++; 1455 } 1456 found = 0; 1457 chr = *q++; 1458 if (squoted && chr == CTLESC) 1459 chr = *q++; 1460 if (chr == '\0') 1461 return 0; 1462 c = *p++; 1463 do { 1464 if (c == CTLQUOTEMARK) 1465 continue; 1466 if (c == CTLESC) 1467 c = *p++; 1468 if (*p == '-' && p[1] != ']') { 1469 p++; 1470 while (*p == CTLQUOTEMARK) 1471 p++; 1472 if (*p == CTLESC) 1473 p++; 1474 if ( collate_range_cmp(chr, c) >= 0 1475 && collate_range_cmp(chr, *p) <= 0 1476 ) 1477 found = 1; 1478 p++; 1479 } else { 1480 if (chr == c) 1481 found = 1; 1482 } 1483 } while ((c = *p++) != ']'); 1484 if (found == invert) 1485 return 0; 1486 break; 1487 } 1488 dft: default: 1489 if (squoted && *q == CTLESC) 1490 q++; 1491 if (*q++ != c) 1492 return 0; 1493 break; 1494 } 1495 } 1496 breakloop: 1497 if (*q != '\0') 1498 return 0; 1499 return 1; 1500 } 1501 1502 1503 1504 /* 1505 * Remove any CTLESC and CTLQUOTEMARK characters from a string. 1506 */ 1507 1508 void 1509 rmescapes(char *str) 1510 { 1511 char *p, *q; 1512 1513 p = str; 1514 while (*p != CTLESC && *p != CTLQUOTEMARK && *p != CTLQUOTEEND) { 1515 if (*p++ == '\0') 1516 return; 1517 } 1518 q = p; 1519 while (*p) { 1520 if (*p == CTLQUOTEMARK || *p == CTLQUOTEEND) { 1521 p++; 1522 continue; 1523 } 1524 if (*p == CTLESC) 1525 p++; 1526 *q++ = *p++; 1527 } 1528 *q = '\0'; 1529 } 1530 1531 1532 1533 /* 1534 * See if a pattern matches in a case statement. 1535 */ 1536 1537 int 1538 casematch(union node *pattern, const char *val) 1539 { 1540 struct stackmark smark; 1541 int result; 1542 char *p; 1543 1544 setstackmark(&smark); 1545 argbackq = pattern->narg.backquote; 1546 STARTSTACKSTR(expdest); 1547 ifslastp = NULL; 1548 argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); 1549 STPUTC('\0', expdest); 1550 p = grabstackstr(expdest); 1551 result = patmatch(p, val, 0); 1552 popstackmark(&smark); 1553 return result; 1554 } 1555 1556 /* 1557 * Our own itoa(). 1558 */ 1559 1560 static char * 1561 cvtnum(int num, char *buf) 1562 { 1563 char temp[32]; 1564 int neg = num < 0; 1565 char *p = temp + 31; 1566 1567 temp[31] = '\0'; 1568 1569 do { 1570 *--p = num % 10 + '0'; 1571 } while ((num /= 10) != 0); 1572 1573 if (neg) 1574 *--p = '-'; 1575 1576 STPUTS(p, buf); 1577 return buf; 1578 } 1579 1580 /* 1581 * Do most of the work for wordexp(3). 1582 */ 1583 1584 int 1585 wordexpcmd(int argc, char **argv) 1586 { 1587 size_t len; 1588 int i; 1589 1590 out1fmt("%08x", argc - 1); 1591 for (i = 1, len = 0; i < argc; i++) 1592 len += strlen(argv[i]); 1593 out1fmt("%08x", (int)len); 1594 for (i = 1; i < argc; i++) 1595 outbin(argv[i], strlen(argv[i]) + 1, out1); 1596 return (0); 1597 } 1598