1 /* $OpenBSD: eval.c,v 1.35 2010/03/24 08:27:26 fgsch Exp $ */ 2 3 /*- 4 * Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 5 * Thorsten Glaser <tg (at) mirbsd.org> 6 * 7 * Provided that these terms and disclaimer and all copyright notices 8 * are retained or reproduced in an accompanying document, permission 9 * is granted to deal in this work without restriction, including un- 10 * limited rights to use, publicly perform, distribute, sell, modify, 11 * merge, give away, or sublicence. 12 * 13 * This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to 14 * the utmost extent permitted by applicable law, neither express nor 15 * implied; without malicious intent or gross negligence. In no event 16 * may a licensor, author or contributor be held liable for indirect, 17 * direct, other damage, loss, or other issues arising in any way out 18 * of dealing in the work, even if advised of the possibility of such 19 * damage or existence of a defect, except proven that it results out 20 * of said person's immediate fault when using the work as intended. 21 */ 22 23 #include "sh.h" 24 25 __RCSID("$MirOS: src/bin/mksh/eval.c,v 1.90 2010/07/17 22:09:33 tg Exp $"); 26 27 /* 28 * string expansion 29 * 30 * first pass: quoting, IFS separation, ~, ${}, $() and $(()) substitution. 31 * second pass: alternation ({,}), filename expansion (*?[]). 32 */ 33 34 /* expansion generator state */ 35 typedef struct Expand { 36 /* int type; */ /* see expand() */ 37 const char *str; /* string */ 38 union { 39 const char **strv; /* string[] */ 40 struct shf *shf; /* file */ 41 } u; /* source */ 42 struct tbl *var; /* variable in ${var..} */ 43 short split; /* split "$@" / call waitlast $() */ 44 } Expand; 45 46 #define XBASE 0 /* scanning original */ 47 #define XSUB 1 /* expanding ${} string */ 48 #define XARGSEP 2 /* ifs0 between "$*" */ 49 #define XARG 3 /* expanding $*, $@ */ 50 #define XCOM 4 /* expanding $() */ 51 #define XNULLSUB 5 /* "$@" when $# is 0 (don't generate word) */ 52 #define XSUBMID 6 /* middle of expanding ${} */ 53 54 /* States used for field splitting */ 55 #define IFS_WORD 0 /* word has chars (or quotes) */ 56 #define IFS_WS 1 /* have seen IFS white-space */ 57 #define IFS_NWS 2 /* have seen IFS non-white-space */ 58 59 static int varsub(Expand *, const char *, const char *, int *, int *); 60 static int comsub(Expand *, const char *); 61 static char *trimsub(char *, char *, int); 62 static void glob(char *, XPtrV *, int); 63 static void globit(XString *, char **, char *, XPtrV *, int); 64 static const char *maybe_expand_tilde(const char *, XString *, char **, int); 65 static char *tilde(char *); 66 #ifndef MKSH_NOPWNAM 67 static char *homedir(char *); 68 #endif 69 static void alt_expand(XPtrV *, char *, char *, char *, int); 70 static size_t utflen(const char *); 71 static void utfincptr(const char *, mksh_ari_t *); 72 73 /* UTFMODE functions */ 74 static size_t 75 utflen(const char *s) 76 { 77 size_t n; 78 79 if (UTFMODE) { 80 n = 0; 81 while (*s) { 82 s += utf_ptradj(s); 83 ++n; 84 } 85 } else 86 n = strlen(s); 87 return (n); 88 } 89 90 static void 91 utfincptr(const char *s, mksh_ari_t *lp) 92 { 93 const char *cp = s; 94 95 while ((*lp)--) 96 cp += utf_ptradj(cp); 97 *lp = cp - s; 98 } 99 100 /* compile and expand word */ 101 char * 102 substitute(const char *cp, int f) 103 { 104 struct source *s, *sold; 105 106 sold = source; 107 s = pushs(SWSTR, ATEMP); 108 s->start = s->str = cp; 109 source = s; 110 if (yylex(ONEWORD) != LWORD) 111 internal_errorf("substitute"); 112 source = sold; 113 afree(s, ATEMP); 114 return (evalstr(yylval.cp, f)); 115 } 116 117 /* 118 * expand arg-list 119 */ 120 char ** 121 eval(const char **ap, int f) 122 { 123 XPtrV w; 124 125 if (*ap == NULL) { 126 union mksh_ccphack vap; 127 128 vap.ro = ap; 129 return (vap.rw); 130 } 131 XPinit(w, 32); 132 XPput(w, NULL); /* space for shell name */ 133 while (*ap != NULL) 134 expand(*ap++, &w, f); 135 XPput(w, NULL); 136 return ((char **)XPclose(w) + 1); 137 } 138 139 /* 140 * expand string 141 */ 142 char * 143 evalstr(const char *cp, int f) 144 { 145 XPtrV w; 146 char *dp = null; 147 148 XPinit(w, 1); 149 expand(cp, &w, f); 150 if (XPsize(w)) 151 dp = *XPptrv(w); 152 XPfree(w); 153 return (dp); 154 } 155 156 /* 157 * expand string - return only one component 158 * used from iosetup to expand redirection files 159 */ 160 char * 161 evalonestr(const char *cp, int f) 162 { 163 XPtrV w; 164 char *rv; 165 166 XPinit(w, 1); 167 expand(cp, &w, f); 168 switch (XPsize(w)) { 169 case 0: 170 rv = null; 171 break; 172 case 1: 173 rv = (char *) *XPptrv(w); 174 break; 175 default: 176 rv = evalstr(cp, f&~DOGLOB); 177 break; 178 } 179 XPfree(w); 180 return (rv); 181 } 182 183 /* for nested substitution: ${var:=$var2} */ 184 typedef struct SubType { 185 struct tbl *var; /* variable for ${var..} */ 186 struct SubType *prev; /* old type */ 187 struct SubType *next; /* poped type (to avoid re-allocating) */ 188 short stype; /* [=+-?%#] action after expanded word */ 189 short base; /* begin position of expanded word */ 190 short f; /* saved value of f (DOPAT, etc) */ 191 uint8_t quotep; /* saved value of quote (for ${..[%#]..}) */ 192 uint8_t quotew; /* saved value of quote (for ${..[+-=]..}) */ 193 } SubType; 194 195 void 196 expand(const char *cp, /* input word */ 197 XPtrV *wp, /* output words */ 198 int f) /* DO* flags */ 199 { 200 int c = 0; 201 int type; /* expansion type */ 202 int quote = 0; /* quoted */ 203 XString ds; /* destination string */ 204 char *dp; /* destination */ 205 const char *sp; /* source */ 206 int fdo, word; /* second pass flags; have word */ 207 int doblank; /* field splitting of parameter/command subst */ 208 Expand x = { /* expansion variables */ 209 NULL, { NULL }, NULL, 0 210 }; 211 SubType st_head, *st; 212 int newlines = 0; /* For trailing newlines in COMSUB */ 213 int saw_eq, tilde_ok; 214 int make_magic; 215 size_t len; 216 217 if (cp == NULL) 218 internal_errorf("expand(NULL)"); 219 /* for alias, readonly, set, typeset commands */ 220 if ((f & DOVACHECK) && is_wdvarassign(cp)) { 221 f &= ~(DOVACHECK|DOBLANK|DOGLOB|DOTILDE); 222 f |= DOASNTILDE; 223 } 224 if (Flag(FNOGLOB)) 225 f &= ~DOGLOB; 226 if (Flag(FMARKDIRS)) 227 f |= DOMARKDIRS; 228 if (Flag(FBRACEEXPAND) && (f & DOGLOB)) 229 f |= DOBRACE_; 230 231 Xinit(ds, dp, 128, ATEMP); /* init dest. string */ 232 type = XBASE; 233 sp = cp; 234 fdo = 0; 235 saw_eq = 0; 236 tilde_ok = (f & (DOTILDE|DOASNTILDE)) ? 1 : 0; /* must be 1/0 */ 237 doblank = 0; 238 make_magic = 0; 239 word = (f&DOBLANK) ? IFS_WS : IFS_WORD; 240 /* clang doesn't know OSUBST comes before CSUBST */ 241 memset(&st_head, 0, sizeof(st_head)); 242 st = &st_head; 243 244 while (1) { 245 Xcheck(ds, dp); 246 247 switch (type) { 248 case XBASE: /* original prefixed string */ 249 c = *sp++; 250 switch (c) { 251 case EOS: 252 c = 0; 253 break; 254 case CHAR: 255 c = *sp++; 256 break; 257 case QCHAR: 258 quote |= 2; /* temporary quote */ 259 c = *sp++; 260 break; 261 case OQUOTE: 262 word = IFS_WORD; 263 tilde_ok = 0; 264 quote = 1; 265 continue; 266 case CQUOTE: 267 quote = st->quotew; 268 continue; 269 case COMSUB: 270 tilde_ok = 0; 271 if (f & DONTRUNCOMMAND) { 272 word = IFS_WORD; 273 *dp++ = '$'; *dp++ = '('; 274 while (*sp != '\0') { 275 Xcheck(ds, dp); 276 *dp++ = *sp++; 277 } 278 *dp++ = ')'; 279 } else { 280 type = comsub(&x, sp); 281 if (type == XCOM && (f&DOBLANK)) 282 doblank++; 283 sp = strnul(sp) + 1; 284 newlines = 0; 285 } 286 continue; 287 case EXPRSUB: 288 word = IFS_WORD; 289 tilde_ok = 0; 290 if (f & DONTRUNCOMMAND) { 291 *dp++ = '$'; *dp++ = '('; *dp++ = '('; 292 while (*sp != '\0') { 293 Xcheck(ds, dp); 294 *dp++ = *sp++; 295 } 296 *dp++ = ')'; *dp++ = ')'; 297 } else { 298 struct tbl v; 299 char *p; 300 301 v.flag = DEFINED|ISSET|INTEGER; 302 v.type = 10; /* not default */ 303 v.name[0] = '\0'; 304 v_evaluate(&v, substitute(sp, 0), 305 KSH_UNWIND_ERROR, true); 306 sp = strnul(sp) + 1; 307 for (p = str_val(&v); *p; ) { 308 Xcheck(ds, dp); 309 *dp++ = *p++; 310 } 311 } 312 continue; 313 case OSUBST: { /* ${{#}var{:}[=+-?#%]word} */ 314 /* format is: 315 * OSUBST [{x] plain-variable-part \0 316 * compiled-word-part CSUBST [}x] 317 * This is where all syntax checking gets done... 318 */ 319 const char *varname = ++sp; /* skip the { or x (}) */ 320 int stype; 321 int slen = 0; 322 323 sp = cstrchr(sp, '\0') + 1; /* skip variable */ 324 type = varsub(&x, varname, sp, &stype, &slen); 325 if (type < 0) { 326 char *beg, *end, *str; 327 328 unwind_substsyn: 329 sp = varname - 2; /* restore sp */ 330 end = (beg = wdcopy(sp, ATEMP)) + 331 (wdscan(sp, CSUBST) - sp); 332 /* ({) the } or x is already skipped */ 333 if (end < wdscan(beg, EOS)) 334 *end = EOS; 335 str = snptreef(NULL, 64, "%S", beg); 336 afree(beg, ATEMP); 337 errorf("%s: bad substitution", str); 338 } 339 if (f & DOBLANK) 340 doblank++; 341 tilde_ok = 0; 342 if (type == XBASE) { /* expand? */ 343 if (!st->next) { 344 SubType *newst; 345 346 newst = alloc(sizeof(SubType), ATEMP); 347 newst->next = NULL; 348 newst->prev = st; 349 st->next = newst; 350 } 351 st = st->next; 352 st->stype = stype; 353 st->base = Xsavepos(ds, dp); 354 st->f = f; 355 st->var = x.var; 356 st->quotew = st->quotep = quote; 357 /* skip qualifier(s) */ 358 if (stype) 359 sp += slen; 360 switch (stype & 0x7f) { 361 case '0': { 362 char *beg, *mid, *end, *stg; 363 mksh_ari_t from = 0, num = -1, flen, finc = 0; 364 365 beg = wdcopy(sp, ATEMP); 366 mid = beg + (wdscan(sp, ADELIM) - sp); 367 stg = beg + (wdscan(sp, CSUBST) - sp); 368 if (mid >= stg) 369 goto unwind_substsyn; 370 mid[-2] = EOS; 371 if (mid[-1] == /*{*/'}') { 372 sp += mid - beg - 1; 373 end = NULL; 374 } else { 375 end = mid + 376 (wdscan(mid, ADELIM) - mid); 377 if (end >= stg) 378 goto unwind_substsyn; 379 end[-2] = EOS; 380 sp += end - beg - 1; 381 } 382 evaluate(substitute(stg = wdstrip(beg, false, false), 0), 383 &from, KSH_UNWIND_ERROR, true); 384 afree(stg, ATEMP); 385 if (end) { 386 evaluate(substitute(stg = wdstrip(mid, false, false), 0), 387 &num, KSH_UNWIND_ERROR, true); 388 afree(stg, ATEMP); 389 } 390 afree(beg, ATEMP); 391 beg = str_val(st->var); 392 flen = utflen(beg); 393 if (from < 0) { 394 if (-from < flen) 395 finc = flen + from; 396 } else 397 finc = from < flen ? from : flen; 398 if (UTFMODE) 399 utfincptr(beg, &finc); 400 beg += finc; 401 flen = utflen(beg); 402 if (num < 0 || num > flen) 403 num = flen; 404 if (UTFMODE) 405 utfincptr(beg, &num); 406 strndupx(x.str, beg, num, ATEMP); 407 goto do_CSUBST; 408 } 409 case '/': { 410 char *s, *p, *d, *sbeg, *end; 411 char *pat, *rrep; 412 char *tpat0, *tpat1, *tpat2; 413 414 s = wdcopy(sp, ATEMP); 415 p = s + (wdscan(sp, ADELIM) - sp); 416 d = s + (wdscan(sp, CSUBST) - sp); 417 if (p >= d) 418 goto unwind_substsyn; 419 p[-2] = EOS; 420 if (p[-1] == /*{*/'}') 421 d = NULL; 422 else 423 d[-2] = EOS; 424 sp += (d ? d : p) - s - 1; 425 tpat0 = wdstrip(s, true, true); 426 pat = substitute(tpat0, 0); 427 if (d) { 428 d = wdstrip(p, true, false); 429 rrep = substitute(d, 0); 430 afree(d, ATEMP); 431 } else 432 rrep = null; 433 afree(s, ATEMP); 434 s = d = pat; 435 while (*s) 436 if (*s != '\\' || 437 s[1] == '%' || 438 s[1] == '#' || 439 s[1] == '\0' || 440 /* XXX really? */ s[1] == '\\' || 441 s[1] == '/') 442 *d++ = *s++; 443 else 444 s++; 445 *d = '\0'; 446 afree(tpat0, ATEMP); 447 448 /* reject empty pattern */ 449 if (!*pat || gmatchx("", pat, false)) 450 goto no_repl; 451 452 /* prepare string on which to work */ 453 strdupx(s, str_val(st->var), ATEMP); 454 sbeg = s; 455 456 /* first see if we have any match at all */ 457 tpat0 = pat; 458 if (*pat == '#') { 459 /* anchor at the beginning */ 460 tpat1 = shf_smprintf("%s%c*", ++tpat0, MAGIC); 461 tpat2 = tpat1; 462 } else if (*pat == '%') { 463 /* anchor at the end */ 464 tpat1 = shf_smprintf("%c*%s", MAGIC, ++tpat0); 465 tpat2 = tpat0; 466 } else { 467 /* float */ 468 tpat1 = shf_smprintf("%c*%s%c*", MAGIC, pat, MAGIC); 469 tpat2 = tpat1 + 2; 470 } 471 again_repl: 472 /* this would not be necessary if gmatchx would return 473 * the start and end values of a match found, like re* 474 */ 475 if (!gmatchx(sbeg, tpat1, false)) 476 goto end_repl; 477 end = strnul(s); 478 /* now anchor the beginning of the match */ 479 if (*pat != '#') 480 while (sbeg <= end) { 481 if (gmatchx(sbeg, tpat2, false)) 482 break; 483 else 484 sbeg++; 485 } 486 /* now anchor the end of the match */ 487 p = end; 488 if (*pat != '%') 489 while (p >= sbeg) { 490 bool gotmatch; 491 492 c = *p; *p = '\0'; 493 gotmatch = gmatchx(sbeg, tpat0, false); 494 *p = c; 495 if (gotmatch) 496 break; 497 p--; 498 } 499 strndupx(end, s, sbeg - s, ATEMP); 500 d = shf_smprintf("%s%s%s", end, rrep, p); 501 afree(end, ATEMP); 502 sbeg = d + (sbeg - s) + strlen(rrep); 503 afree(s, ATEMP); 504 s = d; 505 if (stype & 0x80) 506 goto again_repl; 507 end_repl: 508 afree(tpat1, ATEMP); 509 x.str = s; 510 no_repl: 511 afree(pat, ATEMP); 512 if (rrep != null) 513 afree(rrep, ATEMP); 514 goto do_CSUBST; 515 } 516 case '#': 517 case '%': 518 /* ! DOBLANK,DOBRACE_,DOTILDE */ 519 f = DOPAT | (f&DONTRUNCOMMAND) | 520 DOTEMP_; 521 st->quotew = quote = 0; 522 /* Prepend open pattern (so | 523 * in a trim will work as 524 * expected) 525 */ 526 *dp++ = MAGIC; 527 *dp++ = (char)('@' | 0x80); 528 break; 529 case '=': 530 /* Enabling tilde expansion 531 * after :s here is 532 * non-standard ksh, but is 533 * consistent with rules for 534 * other assignments. Not 535 * sure what POSIX thinks of 536 * this. 537 * Not doing tilde expansion 538 * for integer variables is a 539 * non-POSIX thing - makes 540 * sense though, since ~ is 541 * a arithmetic operator. 542 */ 543 if (!(x.var->flag & INTEGER)) 544 f |= DOASNTILDE|DOTILDE; 545 f |= DOTEMP_; 546 /* These will be done after the 547 * value has been assigned. 548 */ 549 f &= ~(DOBLANK|DOGLOB|DOBRACE_); 550 tilde_ok = 1; 551 break; 552 case '?': 553 f &= ~DOBLANK; 554 f |= DOTEMP_; 555 /* FALLTHROUGH */ 556 default: 557 /* Enable tilde expansion */ 558 tilde_ok = 1; 559 f |= DOTILDE; 560 } 561 } else 562 /* skip word */ 563 sp += wdscan(sp, CSUBST) - sp; 564 continue; 565 } 566 case CSUBST: /* only get here if expanding word */ 567 do_CSUBST: 568 sp++; /* ({) skip the } or x */ 569 tilde_ok = 0; /* in case of ${unset:-} */ 570 *dp = '\0'; 571 quote = st->quotep; 572 f = st->f; 573 if (f&DOBLANK) 574 doblank--; 575 switch (st->stype&0x7f) { 576 case '#': 577 case '%': 578 /* Append end-pattern */ 579 *dp++ = MAGIC; *dp++ = ')'; *dp = '\0'; 580 dp = Xrestpos(ds, dp, st->base); 581 /* Must use st->var since calling 582 * global would break things 583 * like x[i+=1]. 584 */ 585 x.str = trimsub(str_val(st->var), 586 dp, st->stype); 587 if (x.str[0] != '\0' || st->quotep) 588 type = XSUB; 589 else 590 type = XNULLSUB; 591 if (f&DOBLANK) 592 doblank++; 593 st = st->prev; 594 continue; 595 case '=': 596 /* Restore our position and substitute 597 * the value of st->var (may not be 598 * the assigned value in the presence 599 * of integer/right-adj/etc attributes). 600 */ 601 dp = Xrestpos(ds, dp, st->base); 602 /* Must use st->var since calling 603 * global would cause with things 604 * like x[i+=1] to be evaluated twice. 605 */ 606 /* Note: not exported by FEXPORT 607 * in AT&T ksh. 608 */ 609 /* XXX POSIX says readonly is only 610 * fatal for special builtins (setstr 611 * does readonly check). 612 */ 613 len = strlen(dp) + 1; 614 setstr(st->var, 615 debunk(alloc(len, ATEMP), 616 dp, len), KSH_UNWIND_ERROR); 617 x.str = str_val(st->var); 618 type = XSUB; 619 if (f&DOBLANK) 620 doblank++; 621 st = st->prev; 622 continue; 623 case '?': { 624 char *s = Xrestpos(ds, dp, st->base); 625 626 errorf("%s: %s", st->var->name, 627 dp == s ? 628 "parameter null or not set" : 629 (debunk(s, s, strlen(s) + 1), s)); 630 } 631 case '0': 632 case '/': 633 dp = Xrestpos(ds, dp, st->base); 634 type = XSUB; 635 if (f&DOBLANK) 636 doblank++; 637 st = st->prev; 638 continue; 639 } 640 st = st->prev; 641 type = XBASE; 642 continue; 643 644 case OPAT: /* open pattern: *(foo|bar) */ 645 /* Next char is the type of pattern */ 646 make_magic = 1; 647 c = *sp++ + 0x80; 648 break; 649 650 case SPAT: /* pattern separator (|) */ 651 make_magic = 1; 652 c = '|'; 653 break; 654 655 case CPAT: /* close pattern */ 656 make_magic = 1; 657 c = /*(*/ ')'; 658 break; 659 } 660 break; 661 662 case XNULLSUB: 663 /* Special case for "$@" (and "${foo[@]}") - no 664 * word is generated if $# is 0 (unless there is 665 * other stuff inside the quotes). 666 */ 667 type = XBASE; 668 if (f&DOBLANK) { 669 doblank--; 670 /* not really correct: x=; "$x$@" should 671 * generate a null argument and 672 * set A; "${@:+}" shouldn't. 673 */ 674 if (dp == Xstring(ds, dp)) 675 word = IFS_WS; 676 } 677 continue; 678 679 case XSUB: 680 case XSUBMID: 681 if ((c = *x.str++) == 0) { 682 type = XBASE; 683 if (f&DOBLANK) 684 doblank--; 685 continue; 686 } 687 break; 688 689 case XARGSEP: 690 type = XARG; 691 quote = 1; 692 case XARG: 693 if ((c = *x.str++) == '\0') { 694 /* force null words to be created so 695 * set -- '' 2 ''; foo "$@" will do 696 * the right thing 697 */ 698 if (quote && x.split) 699 word = IFS_WORD; 700 if ((x.str = *x.u.strv++) == NULL) { 701 type = XBASE; 702 if (f&DOBLANK) 703 doblank--; 704 continue; 705 } 706 c = ifs0; 707 if (c == 0) { 708 if (quote && !x.split) 709 continue; 710 c = ' '; 711 } 712 if (quote && x.split) { 713 /* terminate word for "$@" */ 714 type = XARGSEP; 715 quote = 0; 716 } 717 } 718 break; 719 720 case XCOM: 721 if (newlines) { /* Spit out saved NLs */ 722 c = '\n'; 723 --newlines; 724 } else { 725 while ((c = shf_getc(x.u.shf)) == 0 || c == '\n') 726 if (c == '\n') 727 /* Save newlines */ 728 newlines++; 729 if (newlines && c != EOF) { 730 shf_ungetc(c, x.u.shf); 731 c = '\n'; 732 --newlines; 733 } 734 } 735 if (c == EOF) { 736 newlines = 0; 737 shf_close(x.u.shf); 738 if (x.split) 739 subst_exstat = waitlast(); 740 type = XBASE; 741 if (f&DOBLANK) 742 doblank--; 743 continue; 744 } 745 break; 746 } 747 748 /* check for end of word or IFS separation */ 749 if (c == 0 || (!quote && (f & DOBLANK) && doblank && 750 !make_magic && ctype(c, C_IFS))) { 751 /* How words are broken up: 752 * | value of c 753 * word | ws nws 0 754 * ----------------------------------- 755 * IFS_WORD w/WS w/NWS w 756 * IFS_WS -/WS w/NWS - 757 * IFS_NWS -/NWS w/NWS w 758 * (w means generate a word) 759 * Note that IFS_NWS/0 generates a word (AT&T ksh 760 * doesn't do this, but POSIX does). 761 */ 762 if (word == IFS_WORD || 763 (!ctype(c, C_IFSWS) && c && word == IFS_NWS)) { 764 char *p; 765 766 *dp++ = '\0'; 767 p = Xclose(ds, dp); 768 if (fdo & DOBRACE_) 769 /* also does globbing */ 770 alt_expand(wp, p, p, 771 p + Xlength(ds, (dp - 1)), 772 fdo | (f & DOMARKDIRS)); 773 else if (fdo & DOGLOB) 774 glob(p, wp, f & DOMARKDIRS); 775 else if ((f & DOPAT) || !(fdo & DOMAGIC_)) 776 XPput(*wp, p); 777 else 778 XPput(*wp, debunk(p, p, strlen(p) + 1)); 779 fdo = 0; 780 saw_eq = 0; 781 tilde_ok = (f & (DOTILDE|DOASNTILDE)) ? 1 : 0; 782 if (c != 0) 783 Xinit(ds, dp, 128, ATEMP); 784 } 785 if (c == 0) 786 return; 787 if (word != IFS_NWS) 788 word = ctype(c, C_IFSWS) ? IFS_WS : IFS_NWS; 789 } else { 790 if (type == XSUB) { 791 if (word == IFS_NWS && 792 Xlength(ds, dp) == 0) { 793 char *p; 794 795 *(p = alloc(1, ATEMP)) = '\0'; 796 XPput(*wp, p); 797 } 798 type = XSUBMID; 799 } 800 801 /* age tilde_ok info - ~ code tests second bit */ 802 tilde_ok <<= 1; 803 /* mark any special second pass chars */ 804 if (!quote) 805 switch (c) { 806 case '[': 807 case NOT: 808 case '-': 809 case ']': 810 /* For character classes - doesn't hurt 811 * to have magic !,-,]s outside of 812 * [...] expressions. 813 */ 814 if (f & (DOPAT | DOGLOB)) { 815 fdo |= DOMAGIC_; 816 if (c == '[') 817 fdo |= f & DOGLOB; 818 *dp++ = MAGIC; 819 } 820 break; 821 case '*': 822 case '?': 823 if (f & (DOPAT | DOGLOB)) { 824 fdo |= DOMAGIC_ | (f & DOGLOB); 825 *dp++ = MAGIC; 826 } 827 break; 828 case OBRACE: 829 case ',': 830 case CBRACE: 831 if ((f & DOBRACE_) && (c == OBRACE || 832 (fdo & DOBRACE_))) { 833 fdo |= DOBRACE_|DOMAGIC_; 834 *dp++ = MAGIC; 835 } 836 break; 837 case '=': 838 /* Note first unquoted = for ~ */ 839 if (!(f & DOTEMP_) && !saw_eq && 840 (Flag(FBRACEEXPAND) || 841 (f & DOASNTILDE))) { 842 saw_eq = 1; 843 tilde_ok = 1; 844 } 845 break; 846 case ':': /* : */ 847 /* Note unquoted : for ~ */ 848 if (!(f & DOTEMP_) && (f & DOASNTILDE)) 849 tilde_ok = 1; 850 break; 851 case '~': 852 /* tilde_ok is reset whenever 853 * any of ' " $( $(( ${ } are seen. 854 * Note that tilde_ok must be preserved 855 * through the sequence ${A=a=}~ 856 */ 857 if (type == XBASE && 858 (f & (DOTILDE|DOASNTILDE)) && 859 (tilde_ok & 2)) { 860 const char *p; 861 char *dp_x; 862 863 dp_x = dp; 864 p = maybe_expand_tilde(sp, 865 &ds, &dp_x, 866 f & DOASNTILDE); 867 if (p) { 868 if (dp != dp_x) 869 word = IFS_WORD; 870 dp = dp_x; 871 sp = p; 872 continue; 873 } 874 } 875 break; 876 } 877 else 878 quote &= ~2; /* undo temporary */ 879 880 if (make_magic) { 881 make_magic = 0; 882 fdo |= DOMAGIC_ | (f & DOGLOB); 883 *dp++ = MAGIC; 884 } else if (ISMAGIC(c)) { 885 fdo |= DOMAGIC_; 886 *dp++ = MAGIC; 887 } 888 *dp++ = c; /* save output char */ 889 word = IFS_WORD; 890 } 891 } 892 } 893 894 /* 895 * Prepare to generate the string returned by ${} substitution. 896 */ 897 static int 898 varsub(Expand *xp, const char *sp, const char *word, 899 int *stypep, /* becomes qualifier type */ 900 int *slenp) /* " " len (=, :=, etc.) valid iff *stypep != 0 */ 901 { 902 int c; 903 int state; /* next state: XBASE, XARG, XSUB, XNULLSUB */ 904 int stype; /* substitution type */ 905 int slen; 906 const char *p; 907 struct tbl *vp; 908 bool zero_ok = false; 909 910 if ((stype = sp[0]) == '\0') /* Bad variable name */ 911 return (-1); 912 913 xp->var = NULL; 914 915 /*- 916 * ${#var}, string length (-U: characters, +U: octets) or array size 917 * ${%var}, string width (-U: screen columns, +U: octets) 918 */ 919 c = sp[1]; 920 if (stype == '%' && c == '\0') 921 return (-1); 922 if ((stype == '#' || stype == '%') && c != '\0') { 923 /* Can't have any modifiers for ${#...} or ${%...} */ 924 if (*word != CSUBST) 925 return (-1); 926 sp++; 927 /* Check for size of array */ 928 if ((p = cstrchr(sp, '[')) && (p[1] == '*' || p[1] == '@') && 929 p[2] == ']') { 930 int n = 0; 931 932 if (stype != '#') 933 return (-1); 934 vp = global(arrayname(sp)); 935 if (vp->flag & (ISSET|ARRAY)) 936 zero_ok = true; 937 for (; vp; vp = vp->u.array) 938 if (vp->flag & ISSET) 939 n++; 940 c = n; 941 } else if (c == '*' || c == '@') { 942 if (stype != '#') 943 return (-1); 944 c = e->loc->argc; 945 } else { 946 p = str_val(global(sp)); 947 zero_ok = p != null; 948 if (stype == '#') 949 c = utflen(p); 950 else { 951 /* partial utf_mbswidth reimplementation */ 952 const char *s = p; 953 unsigned int wc; 954 size_t len; 955 int cw; 956 957 c = 0; 958 while (*s) { 959 if (!UTFMODE || (len = utf_mbtowc(&wc, 960 s)) == (size_t)-1) 961 /* not UTFMODE or not UTF-8 */ 962 wc = (unsigned char)(*s++); 963 else 964 /* UTFMODE and UTF-8 */ 965 s += len; 966 /* wc == char or wchar at s++ */ 967 if ((cw = utf_wcwidth(wc)) == -1) { 968 /* 646, 8859-1, 10646 C0/C1 */ 969 c = -1; 970 break; 971 } 972 c += cw; 973 } 974 } 975 } 976 if (Flag(FNOUNSET) && c == 0 && !zero_ok) 977 errorf("%s: parameter not set", sp); 978 *stypep = 0; /* unqualified variable/string substitution */ 979 xp->str = shf_smprintf("%d", c); 980 return (XSUB); 981 } 982 983 /* Check for qualifiers in word part */ 984 stype = 0; 985 c = word[slen = 0] == CHAR ? word[1] : 0; 986 if (c == ':') { 987 slen += 2; 988 stype = 0x80; 989 c = word[slen + 0] == CHAR ? word[slen + 1] : 0; 990 } 991 if (!stype && c == '/') { 992 slen += 2; 993 stype = c; 994 if (word[slen] == ADELIM) { 995 slen += 2; 996 stype |= 0x80; 997 } 998 } else if (stype == 0x80 && (c == ' ' || c == '0')) { 999 stype |= '0'; 1000 } else if (ctype(c, C_SUBOP1)) { 1001 slen += 2; 1002 stype |= c; 1003 } else if (ctype(c, C_SUBOP2)) { /* Note: ksh88 allows :%, :%%, etc */ 1004 slen += 2; 1005 stype = c; 1006 if (word[slen + 0] == CHAR && c == word[slen + 1]) { 1007 stype |= 0x80; 1008 slen += 2; 1009 } 1010 } else if (stype) /* : is not ok */ 1011 return (-1); 1012 if (!stype && *word != CSUBST) 1013 return (-1); 1014 *stypep = stype; 1015 *slenp = slen; 1016 1017 c = sp[0]; 1018 if (c == '*' || c == '@') { 1019 switch (stype & 0x7f) { 1020 case '=': /* can't assign to a vector */ 1021 case '%': /* can't trim a vector (yet) */ 1022 case '#': 1023 case '0': 1024 case '/': 1025 return (-1); 1026 } 1027 if (e->loc->argc == 0) { 1028 xp->str = null; 1029 xp->var = global(sp); 1030 state = c == '@' ? XNULLSUB : XSUB; 1031 } else { 1032 xp->u.strv = (const char **)e->loc->argv + 1; 1033 xp->str = *xp->u.strv++; 1034 xp->split = c == '@'; /* $@ */ 1035 state = XARG; 1036 } 1037 zero_ok = true; /* POSIX 2009? */ 1038 } else { 1039 if ((p = cstrchr(sp, '[')) && (p[1] == '*' || p[1] == '@') && 1040 p[2] == ']') { 1041 XPtrV wv; 1042 1043 switch (stype & 0x7f) { 1044 case '=': /* can't assign to a vector */ 1045 case '%': /* can't trim a vector (yet) */ 1046 case '#': 1047 case '?': 1048 case '0': 1049 case '/': 1050 return (-1); 1051 } 1052 XPinit(wv, 32); 1053 if ((c = sp[0]) == '!') 1054 ++sp; 1055 vp = global(arrayname(sp)); 1056 for (; vp; vp = vp->u.array) { 1057 if (!(vp->flag&ISSET)) 1058 continue; 1059 XPput(wv, c == '!' ? shf_smprintf("%lu", 1060 arrayindex(vp)) : 1061 str_val(vp)); 1062 } 1063 if (XPsize(wv) == 0) { 1064 xp->str = null; 1065 state = p[1] == '@' ? XNULLSUB : XSUB; 1066 XPfree(wv); 1067 } else { 1068 XPput(wv, 0); 1069 xp->u.strv = (const char **)XPptrv(wv); 1070 xp->str = *xp->u.strv++; 1071 xp->split = p[1] == '@'; /* ${foo[@]} */ 1072 state = XARG; 1073 } 1074 } else { 1075 /* Can't assign things like $! or $1 */ 1076 if ((stype & 0x7f) == '=' && 1077 ctype(*sp, C_VAR1 | C_DIGIT)) 1078 return (-1); 1079 if (*sp == '!' && sp[1]) { 1080 ++sp; 1081 xp->var = global(sp); 1082 if (cstrchr(sp, '[')) { 1083 if (xp->var->flag & ISSET) 1084 xp->str = shf_smprintf("%lu", 1085 arrayindex(xp->var)); 1086 else 1087 xp->str = null; 1088 } else if (xp->var->flag & ISSET) 1089 xp->str = xp->var->name; 1090 else 1091 xp->str = "0"; /* ksh93 compat */ 1092 } else { 1093 xp->var = global(sp); 1094 xp->str = str_val(xp->var); 1095 } 1096 state = XSUB; 1097 } 1098 } 1099 1100 c = stype&0x7f; 1101 /* test the compiler's code generator */ 1102 if (ctype(c, C_SUBOP2) || stype == (0x80 | '0') || c == '/' || 1103 (((stype&0x80) ? *xp->str=='\0' : xp->str==null) ? /* undef? */ 1104 c == '=' || c == '-' || c == '?' : c == '+')) 1105 state = XBASE; /* expand word instead of variable value */ 1106 if (Flag(FNOUNSET) && xp->str == null && !zero_ok && 1107 (ctype(c, C_SUBOP2) || (state != XBASE && c != '+'))) 1108 errorf("%s: parameter not set", sp); 1109 return (state); 1110 } 1111 1112 /* 1113 * Run the command in $(...) and read its output. 1114 */ 1115 static int 1116 comsub(Expand *xp, const char *cp) 1117 { 1118 Source *s, *sold; 1119 struct op *t; 1120 struct shf *shf; 1121 1122 s = pushs(SSTRING, ATEMP); 1123 s->start = s->str = cp; 1124 sold = source; 1125 t = compile(s); 1126 afree(s, ATEMP); 1127 source = sold; 1128 1129 if (t == NULL) 1130 return (XBASE); 1131 1132 if (t != NULL && t->type == TCOM && /* $(<file) */ 1133 *t->args == NULL && *t->vars == NULL && t->ioact != NULL) { 1134 struct ioword *io = *t->ioact; 1135 char *name; 1136 1137 if ((io->flag&IOTYPE) != IOREAD) 1138 errorf("funny $() command: %s", 1139 snptreef(NULL, 32, "%R", io)); 1140 shf = shf_open(name = evalstr(io->name, DOTILDE), O_RDONLY, 0, 1141 SHF_MAPHI|SHF_CLEXEC); 1142 if (shf == NULL) 1143 errorf("%s: cannot open $() input", name); 1144 xp->split = 0; /* no waitlast() */ 1145 } else { 1146 int ofd1, pv[2]; 1147 openpipe(pv); 1148 shf = shf_fdopen(pv[0], SHF_RD, NULL); 1149 ofd1 = savefd(1); 1150 if (pv[1] != 1) { 1151 ksh_dup2(pv[1], 1, false); 1152 close(pv[1]); 1153 } 1154 execute(t, XFORK|XXCOM|XPIPEO, NULL); 1155 restfd(1, ofd1); 1156 startlast(); 1157 xp->split = 1; /* waitlast() */ 1158 } 1159 1160 xp->u.shf = shf; 1161 return (XCOM); 1162 } 1163 1164 /* 1165 * perform #pattern and %pattern substitution in ${} 1166 */ 1167 1168 static char * 1169 trimsub(char *str, char *pat, int how) 1170 { 1171 char *end = strnul(str); 1172 char *p, c; 1173 1174 switch (how & 0xFF) { 1175 case '#': /* shortest at beginning */ 1176 for (p = str; p <= end; p += utf_ptradj(p)) { 1177 c = *p; *p = '\0'; 1178 if (gmatchx(str, pat, false)) { 1179 *p = c; 1180 return (p); 1181 } 1182 *p = c; 1183 } 1184 break; 1185 case '#'|0x80: /* longest match at beginning */ 1186 for (p = end; p >= str; p--) { 1187 c = *p; *p = '\0'; 1188 if (gmatchx(str, pat, false)) { 1189 *p = c; 1190 return (p); 1191 } 1192 *p = c; 1193 } 1194 break; 1195 case '%': /* shortest match at end */ 1196 p = end; 1197 while (p >= str) { 1198 if (gmatchx(p, pat, false)) 1199 goto trimsub_match; 1200 if (UTFMODE) { 1201 char *op = p; 1202 while ((p-- > str) && ((*p & 0xC0) == 0x80)) 1203 ; 1204 if ((p < str) || (p + utf_ptradj(p) != op)) 1205 p = op - 1; 1206 } else 1207 --p; 1208 } 1209 break; 1210 case '%'|0x80: /* longest match at end */ 1211 for (p = str; p <= end; p++) 1212 if (gmatchx(p, pat, false)) { 1213 trimsub_match: 1214 strndupx(end, str, p - str, ATEMP); 1215 return (end); 1216 } 1217 break; 1218 } 1219 1220 return (str); /* no match, return string */ 1221 } 1222 1223 /* 1224 * glob 1225 * Name derived from V6's /etc/glob, the program that expanded filenames. 1226 */ 1227 1228 /* XXX cp not const 'cause slashes are temporarily replaced with NULs... */ 1229 static void 1230 glob(char *cp, XPtrV *wp, int markdirs) 1231 { 1232 int oldsize = XPsize(*wp); 1233 1234 if (glob_str(cp, wp, markdirs) == 0) 1235 XPput(*wp, debunk(cp, cp, strlen(cp) + 1)); 1236 else 1237 qsort(XPptrv(*wp) + oldsize, XPsize(*wp) - oldsize, 1238 sizeof(void *), xstrcmp); 1239 } 1240 1241 #define GF_NONE 0 1242 #define GF_EXCHECK BIT(0) /* do existence check on file */ 1243 #define GF_GLOBBED BIT(1) /* some globbing has been done */ 1244 #define GF_MARKDIR BIT(2) /* add trailing / to directories */ 1245 1246 /* Apply file globbing to cp and store the matching files in wp. Returns 1247 * the number of matches found. 1248 */ 1249 int 1250 glob_str(char *cp, XPtrV *wp, int markdirs) 1251 { 1252 int oldsize = XPsize(*wp); 1253 XString xs; 1254 char *xp; 1255 1256 Xinit(xs, xp, 256, ATEMP); 1257 globit(&xs, &xp, cp, wp, markdirs ? GF_MARKDIR : GF_NONE); 1258 Xfree(xs, xp); 1259 1260 return (XPsize(*wp) - oldsize); 1261 } 1262 1263 static void 1264 globit(XString *xs, /* dest string */ 1265 char **xpp, /* ptr to dest end */ 1266 char *sp, /* source path */ 1267 XPtrV *wp, /* output list */ 1268 int check) /* GF_* flags */ 1269 { 1270 char *np; /* next source component */ 1271 char *xp = *xpp; 1272 char *se; 1273 char odirsep; 1274 1275 /* This to allow long expansions to be interrupted */ 1276 intrcheck(); 1277 1278 if (sp == NULL) { /* end of source path */ 1279 /* We only need to check if the file exists if a pattern 1280 * is followed by a non-pattern (eg, foo*x/bar; no check 1281 * is needed for foo* since the match must exist) or if 1282 * any patterns were expanded and the markdirs option is set. 1283 * Symlinks make things a bit tricky... 1284 */ 1285 if ((check & GF_EXCHECK) || 1286 ((check & GF_MARKDIR) && (check & GF_GLOBBED))) { 1287 #define stat_check() (stat_done ? stat_done : \ 1288 (stat_done = stat(Xstring(*xs, xp), &statb) < 0 \ 1289 ? -1 : 1)) 1290 struct stat lstatb, statb; 1291 int stat_done = 0; /* -1: failed, 1 ok */ 1292 1293 if (lstat(Xstring(*xs, xp), &lstatb) < 0) 1294 return; 1295 /* special case for systems which strip trailing 1296 * slashes from regular files (eg, /etc/passwd/). 1297 * SunOS 4.1.3 does this... 1298 */ 1299 if ((check & GF_EXCHECK) && xp > Xstring(*xs, xp) && 1300 xp[-1] == '/' && !S_ISDIR(lstatb.st_mode) && 1301 (!S_ISLNK(lstatb.st_mode) || 1302 stat_check() < 0 || !S_ISDIR(statb.st_mode))) 1303 return; 1304 /* Possibly tack on a trailing / if there isn't already 1305 * one and if the file is a directory or a symlink to a 1306 * directory 1307 */ 1308 if (((check & GF_MARKDIR) && (check & GF_GLOBBED)) && 1309 xp > Xstring(*xs, xp) && xp[-1] != '/' && 1310 (S_ISDIR(lstatb.st_mode) || 1311 (S_ISLNK(lstatb.st_mode) && stat_check() > 0 && 1312 S_ISDIR(statb.st_mode)))) { 1313 *xp++ = '/'; 1314 *xp = '\0'; 1315 } 1316 } 1317 strndupx(np, Xstring(*xs, xp), Xlength(*xs, xp), ATEMP); 1318 XPput(*wp, np); 1319 return; 1320 } 1321 1322 if (xp > Xstring(*xs, xp)) 1323 *xp++ = '/'; 1324 while (*sp == '/') { 1325 Xcheck(*xs, xp); 1326 *xp++ = *sp++; 1327 } 1328 np = strchr(sp, '/'); 1329 if (np != NULL) { 1330 se = np; 1331 odirsep = *np; /* don't assume '/', can be multiple kinds */ 1332 *np++ = '\0'; 1333 } else { 1334 odirsep = '\0'; /* keep gcc quiet */ 1335 se = sp + strlen(sp); 1336 } 1337 1338 1339 /* Check if sp needs globbing - done to avoid pattern checks for strings 1340 * containing MAGIC characters, open [s without the matching close ], 1341 * etc. (otherwise opendir() will be called which may fail because the 1342 * directory isn't readable - if no globbing is needed, only execute 1343 * permission should be required (as per POSIX)). 1344 */ 1345 if (!has_globbing(sp, se)) { 1346 XcheckN(*xs, xp, se - sp + 1); 1347 debunk(xp, sp, Xnleft(*xs, xp)); 1348 xp += strlen(xp); 1349 *xpp = xp; 1350 globit(xs, xpp, np, wp, check); 1351 } else { 1352 DIR *dirp; 1353 struct dirent *d; 1354 char *name; 1355 int len; 1356 int prefix_len; 1357 1358 /* xp = *xpp; copy_non_glob() may have re-alloc'd xs */ 1359 *xp = '\0'; 1360 prefix_len = Xlength(*xs, xp); 1361 dirp = opendir(prefix_len ? Xstring(*xs, xp) : "."); 1362 if (dirp == NULL) 1363 goto Nodir; 1364 while ((d = readdir(dirp)) != NULL) { 1365 name = d->d_name; 1366 if (name[0] == '.' && 1367 (name[1] == 0 || (name[1] == '.' && name[2] == 0))) 1368 continue; /* always ignore . and .. */ 1369 if ((*name == '.' && *sp != '.') || 1370 !gmatchx(name, sp, true)) 1371 continue; 1372 1373 len = strlen(d->d_name) + 1; 1374 XcheckN(*xs, xp, len); 1375 memcpy(xp, name, len); 1376 *xpp = xp + len - 1; 1377 globit(xs, xpp, np, wp, 1378 (check & GF_MARKDIR) | GF_GLOBBED 1379 | (np ? GF_EXCHECK : GF_NONE)); 1380 xp = Xstring(*xs, xp) + prefix_len; 1381 } 1382 closedir(dirp); 1383 Nodir: 1384 ; 1385 } 1386 1387 if (np != NULL) 1388 *--np = odirsep; 1389 } 1390 1391 /* remove MAGIC from string */ 1392 char * 1393 debunk(char *dp, const char *sp, size_t dlen) 1394 { 1395 char *d; 1396 const char *s; 1397 1398 if ((s = cstrchr(sp, MAGIC))) { 1399 if (s - sp >= (ssize_t)dlen) 1400 return (dp); 1401 memmove(dp, sp, s - sp); 1402 for (d = dp + (s - sp); *s && (d - dp < (ssize_t)dlen); s++) 1403 if (!ISMAGIC(*s) || !(*++s & 0x80) || 1404 !vstrchr("*+?@! ", *s & 0x7f)) 1405 *d++ = *s; 1406 else { 1407 /* extended pattern operators: *+?@! */ 1408 if ((*s & 0x7f) != ' ') 1409 *d++ = *s & 0x7f; 1410 if (d - dp < (ssize_t)dlen) 1411 *d++ = '('; 1412 } 1413 *d = '\0'; 1414 } else if (dp != sp) 1415 strlcpy(dp, sp, dlen); 1416 return (dp); 1417 } 1418 1419 /* Check if p is an unquoted name, possibly followed by a / or :. If so 1420 * puts the expanded version in *dcp,dp and returns a pointer in p just 1421 * past the name, otherwise returns 0. 1422 */ 1423 static const char * 1424 maybe_expand_tilde(const char *p, XString *dsp, char **dpp, int isassign) 1425 { 1426 XString ts; 1427 char *dp = *dpp; 1428 char *tp; 1429 const char *r; 1430 1431 Xinit(ts, tp, 16, ATEMP); 1432 /* : only for DOASNTILDE form */ 1433 while (p[0] == CHAR && p[1] != '/' && (!isassign || p[1] != ':')) 1434 { 1435 Xcheck(ts, tp); 1436 *tp++ = p[1]; 1437 p += 2; 1438 } 1439 *tp = '\0'; 1440 r = (p[0] == EOS || p[0] == CHAR || p[0] == CSUBST) ? 1441 tilde(Xstring(ts, tp)) : NULL; 1442 Xfree(ts, tp); 1443 if (r) { 1444 while (*r) { 1445 Xcheck(*dsp, dp); 1446 if (ISMAGIC(*r)) 1447 *dp++ = MAGIC; 1448 *dp++ = *r++; 1449 } 1450 *dpp = dp; 1451 r = p; 1452 } 1453 return (r); 1454 } 1455 1456 /* 1457 * tilde expansion 1458 * 1459 * based on a version by Arnold Robbins 1460 */ 1461 1462 static char * 1463 tilde(char *cp) 1464 { 1465 char *dp = null; 1466 1467 if (cp[0] == '\0') 1468 dp = str_val(global("HOME")); 1469 else if (cp[0] == '+' && cp[1] == '\0') 1470 dp = str_val(global("PWD")); 1471 else if (cp[0] == '-' && cp[1] == '\0') 1472 dp = str_val(global("OLDPWD")); 1473 #ifndef MKSH_NOPWNAM 1474 else 1475 dp = homedir(cp); 1476 #endif 1477 /* If HOME, PWD or OLDPWD are not set, don't expand ~ */ 1478 return (dp == null ? NULL : dp); 1479 } 1480 1481 #ifndef MKSH_NOPWNAM 1482 /* 1483 * map userid to user's home directory. 1484 * note that 4.3's getpw adds more than 6K to the shell, 1485 * and the YP version probably adds much more. 1486 * we might consider our own version of getpwnam() to keep the size down. 1487 */ 1488 static char * 1489 homedir(char *name) 1490 { 1491 struct tbl *ap; 1492 1493 ap = ktenter(&homedirs, name, hash(name)); 1494 if (!(ap->flag & ISSET)) { 1495 struct passwd *pw; 1496 1497 pw = getpwnam(name); 1498 if (pw == NULL) 1499 return (NULL); 1500 strdupx(ap->val.s, pw->pw_dir, APERM); 1501 ap->flag |= DEFINED|ISSET|ALLOC; 1502 } 1503 return (ap->val.s); 1504 } 1505 #endif 1506 1507 static void 1508 alt_expand(XPtrV *wp, char *start, char *exp_start, char *end, int fdo) 1509 { 1510 int count = 0; 1511 char *brace_start, *brace_end, *comma = NULL; 1512 char *field_start; 1513 char *p; 1514 1515 /* search for open brace */ 1516 for (p = exp_start; (p = strchr(p, MAGIC)) && p[1] != OBRACE; p += 2) 1517 ; 1518 brace_start = p; 1519 1520 /* find matching close brace, if any */ 1521 if (p) { 1522 comma = NULL; 1523 count = 1; 1524 for (p += 2; *p && count; p++) { 1525 if (ISMAGIC(*p)) { 1526 if (*++p == OBRACE) 1527 count++; 1528 else if (*p == CBRACE) 1529 --count; 1530 else if (*p == ',' && count == 1) 1531 comma = p; 1532 } 1533 } 1534 } 1535 /* no valid expansions... */ 1536 if (!p || count != 0) { 1537 /* Note that given a{{b,c} we do not expand anything (this is 1538 * what AT&T ksh does. This may be changed to do the {b,c} 1539 * expansion. } 1540 */ 1541 if (fdo & DOGLOB) 1542 glob(start, wp, fdo & DOMARKDIRS); 1543 else 1544 XPput(*wp, debunk(start, start, end - start)); 1545 return; 1546 } 1547 brace_end = p; 1548 if (!comma) { 1549 alt_expand(wp, start, brace_end, end, fdo); 1550 return; 1551 } 1552 1553 /* expand expression */ 1554 field_start = brace_start + 2; 1555 count = 1; 1556 for (p = brace_start + 2; p != brace_end; p++) { 1557 if (ISMAGIC(*p)) { 1558 if (*++p == OBRACE) 1559 count++; 1560 else if ((*p == CBRACE && --count == 0) || 1561 (*p == ',' && count == 1)) { 1562 char *news; 1563 int l1, l2, l3; 1564 1565 l1 = brace_start - start; 1566 l2 = (p - 1) - field_start; 1567 l3 = end - brace_end; 1568 news = alloc(l1 + l2 + l3 + 1, ATEMP); 1569 memcpy(news, start, l1); 1570 memcpy(news + l1, field_start, l2); 1571 memcpy(news + l1 + l2, brace_end, l3); 1572 news[l1 + l2 + l3] = '\0'; 1573 alt_expand(wp, news, news + l1, 1574 news + l1 + l2 + l3, fdo); 1575 field_start = p + 1; 1576 } 1577 } 1578 } 1579 return; 1580 } 1581