1 /* $NetBSD: eval.c,v 1.12 2009/11/24 16:00:42 seanb Exp $ */ 2 3 /* 4 * Expansion - quoting, separation, substitution, globbing 5 */ 6 #include <sys/cdefs.h> 7 8 #ifndef lint 9 __RCSID("$NetBSD: eval.c,v 1.12 2009/11/24 16:00:42 seanb Exp $"); 10 #endif 11 12 13 #include "sh.h" 14 #include <pwd.h> 15 #include "ksh_dir.h" 16 #include "ksh_stat.h" 17 18 /* 19 * string expansion 20 * 21 * first pass: quoting, IFS separation, ~, ${}, $() and $(()) substitution. 22 * second pass: alternation ({,}), filename expansion (*?[]). 23 */ 24 25 /* expansion generator state */ 26 typedef struct Expand { 27 /* int type; */ /* see expand() */ 28 const char *str; /* string */ 29 union { 30 const char **strv;/* string[] */ 31 struct shf *shf;/* file */ 32 } u; /* source */ 33 struct tbl *var; /* variable in ${var..} */ 34 short split; /* split "$@" / call waitlast $() */ 35 } Expand; 36 37 #define XBASE 0 /* scanning original */ 38 #define XSUB 1 /* expanding ${} string */ 39 #define XARGSEP 2 /* ifs0 between "$*" */ 40 #define XARG 3 /* expanding $*, $@ */ 41 #define XCOM 4 /* expanding $() */ 42 #define XNULLSUB 5 /* "$@" when $# is 0 (don't generate word) */ 43 44 /* States used for field splitting */ 45 #define IFS_WORD 0 /* word has chars (or quotes) */ 46 #define IFS_WS 1 /* have seen IFS white-space */ 47 #define IFS_NWS 2 /* have seen IFS non-white-space */ 48 49 static int varsub ARGS((Expand *xp, char *sp, char *word, int *stypep, int *slenp)); 50 static int comsub ARGS((Expand *xp, char *cp)); 51 static char *trimsub ARGS((char *str, char *pat, int how)); 52 static void glob ARGS((char *cp, XPtrV *wp, int markdirs)); 53 static void globit ARGS((XString *xs, char **xpp, char *sp, XPtrV *wp, 54 int check)); 55 static char *maybe_expand_tilde ARGS((char *p, XString *dsp, char **dpp, 56 int isassign)); 57 static char *tilde ARGS((char *acp)); 58 static char *homedir ARGS((char *name)); 59 #ifdef BRACE_EXPAND 60 static void alt_expand ARGS((XPtrV *wp, char *start, char *exp_start, 61 char *end, int fdo)); 62 #endif 63 64 /* compile and expand word */ 65 char * 66 substitute(cp, f) 67 const char *cp; 68 int f; 69 { 70 struct source *s, *sold; 71 72 sold = source; 73 s = pushs(SWSTR, ATEMP); 74 s->start = s->str = cp; 75 source = s; 76 if (yylex(ONEWORD) != LWORD) 77 internal_errorf(1, "substitute"); 78 source = sold; 79 afree(s, ATEMP); 80 return evalstr(yylval.cp, f); 81 } 82 83 /* 84 * expand arg-list 85 */ 86 char ** 87 eval(ap, f) 88 register char **ap; 89 int f; 90 { 91 XPtrV w; 92 93 if (*ap == NULL) 94 return ap; 95 XPinit(w, 32); 96 XPput(w, NULL); /* space for shell name */ 97 #ifdef SHARPBANG 98 XPput(w, NULL); /* and space for one arg */ 99 #endif 100 while (*ap != NULL) 101 expand(*ap++, &w, f); 102 XPput(w, NULL); 103 #ifdef SHARPBANG 104 return (char **) XPclose(w) + 2; 105 #else 106 return (char **) XPclose(w) + 1; 107 #endif 108 } 109 110 /* 111 * expand string 112 */ 113 char * 114 evalstr(cp, f) 115 char *cp; 116 int f; 117 { 118 XPtrV w; 119 120 XPinit(w, 1); 121 expand(cp, &w, f); 122 cp = (XPsize(w) == 0) ? null : (char*) *XPptrv(w); 123 XPfree(w); 124 return cp; 125 } 126 127 /* 128 * expand string - return only one component 129 * used from iosetup to expand redirection files 130 */ 131 char * 132 evalonestr(cp, f) 133 register char *cp; 134 int f; 135 { 136 XPtrV w; 137 138 XPinit(w, 1); 139 expand(cp, &w, f); 140 switch (XPsize(w)) { 141 case 0: 142 cp = null; 143 break; 144 case 1: 145 cp = (char*) *XPptrv(w); 146 break; 147 default: 148 cp = evalstr(cp, f&~DOGLOB); 149 break; 150 } 151 XPfree(w); 152 return cp; 153 } 154 155 /* for nested substitution: ${var:=$var2} */ 156 typedef struct SubType { 157 short stype; /* [=+-?%#] action after expanded word */ 158 short base; /* begin position of expanded word */ 159 short f; /* saved value of f (DOPAT, etc) */ 160 struct tbl *var; /* variable for ${var..} */ 161 short quote; /* saved value of quote (for ${..[%#]..}) */ 162 struct SubType *prev; /* old type */ 163 struct SubType *next; /* poped type (to avoid re-allocating) */ 164 } SubType; 165 166 void 167 expand(cp, wp, f) 168 char *cp; /* input word */ 169 register XPtrV *wp; /* output words */ 170 int f; /* DO* flags */ 171 { 172 register int UNINITIALIZED(c); 173 register int type; /* expansion type */ 174 register int quote = 0; /* quoted */ 175 XString ds; /* destination string */ 176 register char *dp, *sp; /* dest., source */ 177 int fdo, word; /* second pass flags; have word */ 178 int doblank; /* field splitting of parameter/command subst */ 179 Expand x; /* expansion variables */ 180 SubType st_head, *st; 181 int UNINITIALIZED(newlines); /* For trailing newlines in COMSUB */ 182 int saw_eq, tilde_ok; 183 int make_magic; 184 size_t len; 185 186 x.split = 0; /* XXX gcc */ 187 x.str = NULL; /* XXX gcc */ 188 if (cp == NULL) 189 internal_errorf(1, "expand(NULL)"); 190 /* for alias, readonly, set, typeset commands */ 191 if ((f & DOVACHECK) && is_wdvarassign(cp)) { 192 f &= ~(DOVACHECK|DOBLANK|DOGLOB|DOTILDE); 193 f |= DOASNTILDE; 194 } 195 if (Flag(FNOGLOB)) 196 f &= ~DOGLOB; 197 if (Flag(FMARKDIRS)) 198 f |= DOMARKDIRS; 199 #ifdef BRACE_EXPAND 200 if (Flag(FBRACEEXPAND) && (f & DOGLOB)) 201 f |= DOBRACE_; 202 #endif /* BRACE_EXPAND */ 203 204 Xinit(ds, dp, 128, ATEMP); /* init dest. string */ 205 type = XBASE; 206 sp = cp; 207 fdo = 0; 208 saw_eq = 0; 209 tilde_ok = (f & (DOTILDE|DOASNTILDE)) ? 1 : 0; /* must be 1/0 */ 210 doblank = 0; 211 make_magic = 0; 212 word = (f&DOBLANK) ? IFS_WS : IFS_WORD; 213 st_head.next = (SubType *) 0; 214 st = &st_head; 215 216 while (1) { 217 Xcheck(ds, dp); 218 219 switch (type) { 220 case XBASE: /* original prefixed string */ 221 c = *sp++; 222 switch (c) { 223 case EOS: 224 c = 0; 225 break; 226 case CHAR: 227 c = *sp++; 228 break; 229 case QCHAR: 230 quote |= 2; /* temporary quote */ 231 c = *sp++; 232 break; 233 case OQUOTE: 234 word = IFS_WORD; 235 tilde_ok = 0; 236 quote = 1; 237 continue; 238 case CQUOTE: 239 quote = 0; 240 continue; 241 case COMSUB: 242 tilde_ok = 0; 243 if (f & DONTRUNCOMMAND) { 244 word = IFS_WORD; 245 *dp++ = '$'; *dp++ = '('; 246 while (*sp != '\0') { 247 Xcheck(ds, dp); 248 *dp++ = *sp++; 249 } 250 *dp++ = ')'; 251 } else { 252 type = comsub(&x, sp); 253 if (type == XCOM && (f&DOBLANK)) 254 doblank++; 255 sp = strchr(sp, 0) + 1; 256 newlines = 0; 257 } 258 continue; 259 case EXPRSUB: 260 word = IFS_WORD; 261 tilde_ok = 0; 262 if (f & DONTRUNCOMMAND) { 263 *dp++ = '$'; *dp++ = '('; *dp++ = '('; 264 while (*sp != '\0') { 265 Xcheck(ds, dp); 266 *dp++ = *sp++; 267 } 268 *dp++ = ')'; *dp++ = ')'; 269 } else { 270 struct tbl v; 271 char *p; 272 273 v.flag = DEFINED|ISSET|INTEGER; 274 v.type = 10; /* not default */ 275 v.name[0] = '\0'; 276 v_evaluate(&v, substitute(sp, 0), 277 KSH_UNWIND_ERROR); 278 sp = strchr(sp, 0) + 1; 279 for (p = str_val(&v); *p; ) { 280 Xcheck(ds, dp); 281 *dp++ = *p++; 282 } 283 } 284 continue; 285 case OSUBST: /* ${{#}var{:}[=+-?#%]word} */ 286 /* format is: 287 * OSUBST [{x] plain-variable-part \0 288 * compiled-word-part CSUBST [}x] 289 * This is were all syntax checking gets done... 290 */ 291 { 292 char *varname = ++sp; /* skip the { or x (}) */ 293 int stype; 294 int slen; 295 296 slen = -1; /* XXX gcc */ 297 sp = strchr(sp, '\0') + 1; /* skip variable */ 298 type = varsub(&x, varname, sp, &stype, &slen); 299 if (type < 0) { 300 char endc; 301 char *str, *end; 302 303 end = (char *) wdscan(sp, CSUBST); 304 /* ({) the } or x is already skipped */ 305 endc = *end; 306 *end = EOS; 307 str = snptreef((char *) 0, 64, "%S", 308 varname - 1); 309 *end = endc; 310 errorf("%s: bad substitution", str); 311 } 312 if (f&DOBLANK) 313 doblank++; 314 tilde_ok = 0; 315 if (type == XBASE) { /* expand? */ 316 if (!st->next) { 317 SubType *newst; 318 319 newst = (SubType *) alloc( 320 sizeof(SubType), ATEMP); 321 newst->next = (SubType *) 0; 322 newst->prev = st; 323 st->next = newst; 324 } 325 st = st->next; 326 st->stype = stype; 327 st->base = Xsavepos(ds, dp); 328 st->f = f; 329 st->var = x.var; 330 st->quote = quote; 331 /* skip qualifier(s) */ 332 if (stype) 333 sp += slen; 334 switch (stype & 0x7f) { 335 case '#': 336 case '%': 337 /* ! DOBLANK,DOBRACE_,DOTILDE */ 338 f = DOPAT | (f&DONTRUNCOMMAND) 339 | DOTEMP_; 340 quote = 0; 341 /* Prepend open pattern (so | 342 * in a trim will work as 343 * expected) 344 */ 345 *dp++ = MAGIC; 346 *dp++ = '@' + 0x80; 347 break; 348 case '=': 349 /* Enabling tilde expansion 350 * after :'s here is 351 * non-standard ksh, but is 352 * consistent with rules for 353 * other assignments. Not 354 * sure what POSIX thinks of 355 * this. 356 * Not doing tilde expansion 357 * for integer variables is a 358 * non-POSIX thing - makes 359 * sense though, since ~ is 360 * a arithmetic operator. 361 */ 362 if (!(x.var->flag & INTEGER)) 363 f |= DOASNTILDE|DOTILDE; 364 f |= DOTEMP_; 365 /* These will be done after the 366 * value has been assigned. 367 */ 368 f &= ~(DOBLANK|DOGLOB|DOBRACE_); 369 tilde_ok = 1; 370 break; 371 case '?': 372 f &= ~DOBLANK; 373 f |= DOTEMP_; 374 /* fall through */ 375 default: 376 /* Enable tilde expansion */ 377 tilde_ok = 1; 378 f |= DOTILDE; 379 } 380 } else 381 /* skip word */ 382 sp = (char *) wdscan(sp, CSUBST); 383 continue; 384 } 385 case CSUBST: /* only get here if expanding word */ 386 sp++; /* ({) skip the } or x */ 387 tilde_ok = 0; /* in case of ${unset:-} */ 388 *dp = '\0'; 389 quote = st->quote; 390 f = st->f; 391 if (f&DOBLANK) 392 doblank--; 393 switch (st->stype&0x7f) { 394 case '#': 395 case '%': 396 /* Append end-pattern */ 397 *dp++ = MAGIC; *dp++ = ')'; *dp = '\0'; 398 dp = Xrestpos(ds, dp, st->base); 399 /* Must use st->var since calling 400 * global would break things 401 * like x[i+=1]. 402 */ 403 x.str = trimsub(str_val(st->var), 404 dp, st->stype); 405 type = XSUB; 406 if (f&DOBLANK) 407 doblank++; 408 st = st->prev; 409 continue; 410 case '=': 411 /* Restore our position and substitute 412 * the value of st->var (may not be 413 * the assigned value in the presence 414 * of integer/right-adj/etc attributes). 415 */ 416 dp = Xrestpos(ds, dp, st->base); 417 /* Must use st->var since calling 418 * global would cause with things 419 * like x[i+=1] to be evaluated twice. 420 */ 421 /* Note: not exported by FEXPORT 422 * in at&t ksh. 423 */ 424 /* XXX POSIX says readonly is only 425 * fatal for special builtins (setstr 426 * does readonly check). 427 */ 428 len = strlen(dp) + 1; 429 setstr(st->var, 430 debunk((char *) alloc(len, ATEMP), 431 dp, len), 432 KSH_UNWIND_ERROR); 433 x.str = str_val(st->var); 434 type = XSUB; 435 if (f&DOBLANK) 436 doblank++; 437 st = st->prev; 438 continue; 439 case '?': 440 { 441 char *s = Xrestpos(ds, dp, st->base); 442 443 errorf("%s: %s", st->var->name, 444 dp == s ? 445 "parameter null or not set" 446 : (debunk(s, s, strlen(s) + 1), s)); 447 } 448 } 449 st = st->prev; 450 type = XBASE; 451 continue; 452 453 case OPAT: /* open pattern: *(foo|bar) */ 454 /* Next char is the type of pattern */ 455 make_magic = 1; 456 c = *sp++ + 0x80; 457 break; 458 459 case SPAT: /* pattern separator (|) */ 460 make_magic = 1; 461 c = '|'; 462 break; 463 464 case CPAT: /* close pattern */ 465 make_magic = 1; 466 c = /*(*/ ')'; 467 break; 468 } 469 break; 470 471 case XNULLSUB: 472 /* Special case for "$@" (and "${foo[@]}") - no 473 * word is generated if $# is 0 (unless there is 474 * other stuff inside the quotes). 475 */ 476 type = XBASE; 477 if (f&DOBLANK) { 478 doblank--; 479 /* not really correct: x=; "$x$@" should 480 * generate a null argument and 481 * set A; "${@:+}" shouldn't. 482 */ 483 if (dp == Xstring(ds, dp)) 484 word = IFS_WS; 485 } 486 continue; 487 488 case XSUB: 489 if ((c = *x.str++) == 0) { 490 type = XBASE; 491 if (f&DOBLANK) 492 doblank--; 493 continue; 494 } 495 break; 496 497 case XARGSEP: 498 type = XARG; 499 quote = 1; 500 case XARG: 501 if ((c = *x.str++) == '\0') { 502 /* force null words to be created so 503 * set -- '' 2 ''; foo "$@" will do 504 * the right thing 505 */ 506 if (quote && x.split) 507 word = IFS_WORD; 508 if ((x.str = *x.u.strv++) == NULL) { 509 type = XBASE; 510 if (f&DOBLANK) 511 doblank--; 512 continue; 513 } 514 c = ifs0; 515 if (c == 0) { 516 if (quote && !x.split) 517 continue; 518 c = ' '; 519 } 520 if (quote && x.split) { 521 /* terminate word for "$@" */ 522 type = XARGSEP; 523 quote = 0; 524 } 525 } 526 break; 527 528 case XCOM: 529 if (newlines) { /* Spit out saved nl's */ 530 c = '\n'; 531 --newlines; 532 } else { 533 while ((c = shf_getc(x.u.shf)) == 0 || c == '\n') 534 if (c == '\n') 535 newlines++; /* Save newlines */ 536 if (newlines && c != EOF) { 537 shf_ungetc(c, x.u.shf); 538 c = '\n'; 539 --newlines; 540 } 541 } 542 if (c == EOF) { 543 newlines = 0; 544 shf_close(x.u.shf); 545 if (x.split) 546 subst_exstat = waitlast(); 547 type = XBASE; 548 if (f&DOBLANK) 549 doblank--; 550 continue; 551 } 552 break; 553 } 554 555 /* check for end of word or IFS separation */ 556 if (c == 0 || (!quote && (f & DOBLANK) && doblank && !make_magic 557 && ctype(c, C_IFS))) 558 { 559 /* How words are broken up: 560 * | value of c 561 * word | ws nws 0 562 * ----------------------------------- 563 * IFS_WORD w/WS w/NWS w 564 * IFS_WS -/WS w/NWS - 565 * IFS_NWS -/NWS w/NWS w 566 * (w means generate a word) 567 * Note that IFS_NWS/0 generates a word (at&t ksh 568 * doesn't do this, but POSIX does). 569 */ 570 if (word == IFS_WORD 571 || (!ctype(c, C_IFSWS) && (c || word == IFS_NWS))) 572 { 573 char *p; 574 575 *dp++ = '\0'; 576 p = Xclose(ds, dp); 577 #ifdef BRACE_EXPAND 578 if (fdo & DOBRACE_) 579 /* also does globbing */ 580 alt_expand(wp, p, p, 581 p + Xlength(ds, (dp - 1)), 582 fdo | (f & DOMARKDIRS)); 583 else 584 #endif /* BRACE_EXPAND */ 585 if (fdo & DOGLOB) 586 glob(p, wp, f & DOMARKDIRS); 587 else if ((f & DOPAT) || !(fdo & DOMAGIC_)) 588 XPput(*wp, p); 589 else 590 XPput(*wp, debunk(p, p, strlen(p) + 1)); 591 fdo = 0; 592 saw_eq = 0; 593 tilde_ok = (f & (DOTILDE|DOASNTILDE)) ? 1 : 0; 594 if (c != 0) 595 Xinit(ds, dp, 128, ATEMP); 596 } 597 if (c == 0) 598 return; 599 if (word != IFS_NWS) 600 word = ctype(c, C_IFSWS) ? IFS_WS : IFS_NWS; 601 } else { 602 /* age tilde_ok info - ~ code tests second bit */ 603 tilde_ok <<= 1; 604 /* mark any special second pass chars */ 605 if (!quote) 606 switch (c) { 607 case '[': 608 case NOT: 609 case '-': 610 case ']': 611 /* For character classes - doesn't hurt 612 * to have magic !,-,]'s outside of 613 * [...] expressions. 614 */ 615 if (f & (DOPAT | DOGLOB)) { 616 fdo |= DOMAGIC_; 617 if (c == '[') 618 fdo |= f & DOGLOB; 619 *dp++ = MAGIC; 620 } 621 break; 622 case '*': 623 case '?': 624 if (f & (DOPAT | DOGLOB)) { 625 fdo |= DOMAGIC_ | (f & DOGLOB); 626 *dp++ = MAGIC; 627 } 628 break; 629 #ifdef BRACE_EXPAND 630 case OBRACE: 631 case ',': 632 case CBRACE: 633 if ((f & DOBRACE_) && (c == OBRACE 634 || (fdo & DOBRACE_))) 635 { 636 fdo |= DOBRACE_|DOMAGIC_; 637 *dp++ = MAGIC; 638 } 639 break; 640 #endif /* BRACE_EXPAND */ 641 case '=': 642 /* Note first unquoted = for ~ */ 643 if (!(f & DOTEMP_) && !saw_eq) { 644 saw_eq = 1; 645 tilde_ok = 1; 646 } 647 break; 648 case PATHSEP: /* : */ 649 /* Note unquoted : for ~ */ 650 if (!(f & DOTEMP_) && (f & DOASNTILDE)) 651 tilde_ok = 1; 652 break; 653 case '~': 654 /* tilde_ok is reset whenever 655 * any of ' " $( $(( ${ } are seen. 656 * Note that tilde_ok must be preserved 657 * through the sequence ${A=a=}~ 658 */ 659 if (type == XBASE 660 && (f & (DOTILDE|DOASNTILDE)) 661 && (tilde_ok & 2)) 662 { 663 char *p, *dp_x; 664 665 dp_x = dp; 666 p = maybe_expand_tilde(sp, 667 &ds, &dp_x, 668 f & DOASNTILDE); 669 if (p) { 670 if (dp != dp_x) 671 word = IFS_WORD; 672 dp = dp_x; 673 sp = p; 674 continue; 675 } 676 } 677 break; 678 } 679 else 680 quote &= ~2; /* undo temporary */ 681 682 if (make_magic) { 683 make_magic = 0; 684 fdo |= DOMAGIC_ | (f & DOGLOB); 685 *dp++ = MAGIC; 686 } else if (ISMAGIC(c)) { 687 fdo |= DOMAGIC_; 688 *dp++ = MAGIC; 689 } 690 *dp++ = c; /* save output char */ 691 word = IFS_WORD; 692 } 693 } 694 } 695 696 /* 697 * Prepare to generate the string returned by ${} substitution. 698 */ 699 static int 700 varsub(xp, sp, word, stypep, slenp) 701 Expand *xp; 702 char *sp; 703 char *word; 704 int *stypep; /* becomes qualifier type */ 705 int *slenp; /* " " len (=, :=, etc.) valid iff *stypep != 0 */ 706 { 707 int c; 708 int state; /* next state: XBASE, XARG, XSUB, XNULLSUB */ 709 int stype; /* substitution type */ 710 int slen; 711 char *p; 712 struct tbl *vp; 713 714 if (sp[0] == '\0') /* Bad variable name */ 715 return -1; 716 717 xp->var = (struct tbl *) 0; 718 719 /* ${#var}, string length or array size */ 720 if (sp[0] == '#' && (c = sp[1]) != '\0') { 721 int zero_ok = 0; 722 723 /* Can't have any modifiers for ${#...} */ 724 if (*word != CSUBST) 725 return -1; 726 sp++; 727 /* Check for size of array */ 728 if ((p=strchr(sp,'[')) && (p[1]=='*'||p[1]=='@') && p[2]==']') { 729 int n = 0; 730 int max = 0; 731 vp = global(arrayname(sp)); 732 if (vp->flag & (ISSET|ARRAY)) 733 zero_ok = 1; 734 for (; vp; vp = vp->u.array) 735 if (vp->flag & ISSET) { 736 max = vp->index + 1; 737 n++; 738 } 739 c = n; /* ksh88/ksh93 go for number, not max index */ 740 } else if (c == '*' || c == '@') 741 c = e->loc->argc; 742 else { 743 p = str_val(global(sp)); 744 zero_ok = p != null; 745 c = strlen(p); 746 } 747 if (Flag(FNOUNSET) && c == 0 && !zero_ok) 748 errorf("%s: parameter not set", sp); 749 *stypep = 0; /* unqualified variable/string substitution */ 750 xp->str = str_save(ulton((unsigned long)c, 10), ATEMP); 751 return XSUB; 752 } 753 754 /* Check for qualifiers in word part */ 755 stype = 0; 756 c = word[slen = 0] == CHAR ? word[1] : 0; 757 if (c == ':') { 758 slen += 2; 759 stype = 0x80; 760 c = word[slen + 0] == CHAR ? word[slen + 1] : 0; 761 } 762 if (ctype(c, C_SUBOP1)) { 763 slen += 2; 764 stype |= c; 765 } else if (ctype(c, C_SUBOP2)) { /* Note: ksh88 allows :%, :%%, etc */ 766 slen += 2; 767 stype = c; 768 if (word[slen + 0] == CHAR && c == word[slen + 1]) { 769 stype |= 0x80; 770 slen += 2; 771 } 772 } else if (stype) /* : is not ok */ 773 return -1; 774 if (!stype && *word != CSUBST) 775 return -1; 776 *stypep = stype; 777 *slenp = slen; 778 779 c = sp[0]; 780 if (c == '*' || c == '@') { 781 switch (stype & 0x7f) { 782 case '=': /* can't assign to a vector */ 783 case '%': /* can't trim a vector (yet) */ 784 case '#': 785 return -1; 786 } 787 if (e->loc->argc == 0) { 788 xp->str = null; 789 state = c == '@' ? XNULLSUB : XSUB; 790 } else { 791 xp->u.strv = (const char **) e->loc->argv + 1; 792 xp->str = *xp->u.strv++; 793 xp->split = c == '@'; /* $@ */ 794 state = XARG; 795 } 796 } else { 797 if ((p=strchr(sp,'[')) && (p[1]=='*'||p[1]=='@') && p[2]==']') { 798 XPtrV wv; 799 800 switch (stype & 0x7f) { 801 case '=': /* can't assign to a vector */ 802 case '%': /* can't trim a vector (yet) */ 803 case '#': 804 return -1; 805 } 806 XPinit(wv, 32); 807 vp = global(arrayname(sp)); 808 for (; vp; vp = vp->u.array) { 809 if (!(vp->flag&ISSET)) 810 continue; 811 XPput(wv, str_val(vp)); 812 } 813 if (XPsize(wv) == 0) { 814 xp->str = null; 815 state = p[1] == '@' ? XNULLSUB : XSUB; 816 XPfree(wv); 817 } else { 818 XPput(wv, 0); 819 xp->u.strv = (const char **) XPptrv(wv); 820 xp->str = *xp->u.strv++; 821 xp->split = p[1] == '@'; /* ${foo[@]} */ 822 state = XARG; 823 } 824 } else { 825 /* Can't assign things like $! or $1 */ 826 if ((stype & 0x7f) == '=' 827 && (ctype(*sp, C_VAR1) || digit(*sp))) 828 return -1; 829 xp->var = global(sp); 830 xp->str = str_val(xp->var); 831 state = XSUB; 832 } 833 } 834 835 c = stype&0x7f; 836 /* test the compiler's code generator */ 837 if (ctype(c, C_SUBOP2) || 838 (((stype&0x80) ? *xp->str=='\0' : xp->str==null) ? /* undef? */ 839 c == '=' || c == '-' || c == '?' : c == '+')) 840 state = XBASE; /* expand word instead of variable value */ 841 if (Flag(FNOUNSET) && xp->str == null 842 && (ctype(c, C_SUBOP2) || (state != XBASE && c != '+'))) 843 errorf("%s: parameter not set", sp); 844 return state; 845 } 846 847 /* 848 * Run the command in $(...) and read its output. 849 */ 850 static int 851 comsub(xp, cp) 852 register Expand *xp; 853 char *cp; 854 { 855 Source *s, *sold; 856 register struct op *t; 857 struct shf *shf; 858 859 s = pushs(SSTRING, ATEMP); 860 s->start = s->str = cp; 861 sold = source; 862 t = compile(s); 863 afree(s, ATEMP); 864 source = sold; 865 866 if (t == NULL) 867 return XBASE; 868 869 if (t != NULL && t->type == TCOM && /* $(<file) */ 870 *t->args == NULL && *t->vars == NULL && t->ioact != NULL) { 871 register struct ioword *io = *t->ioact; 872 char *name; 873 874 if ((io->flag&IOTYPE) != IOREAD) 875 errorf("funny $() command: %s", 876 snptreef((char *) 0, 32, "%R", io)); 877 shf = shf_open(name = evalstr(io->name, DOTILDE), O_RDONLY, 0, 878 SHF_MAPHI|SHF_CLEXEC); 879 if (shf == NULL) 880 errorf("%s: cannot open $() input", name); 881 xp->split = 0; /* no waitlast() */ 882 } else { 883 int ofd1, pv[2]; 884 openpipe(pv); 885 shf = shf_fdopen(pv[0], SHF_RD, (struct shf *) 0); 886 ofd1 = savefd(1, 0); /* fd 1 may be closed... */ 887 if (pv[1] != 1) { 888 ksh_dup2(pv[1], 1, FALSE); 889 close(pv[1]); 890 } 891 execute(t, XFORK|XXCOM|XPIPEO); 892 restfd(1, ofd1); 893 startlast(); 894 xp->split = 1; /* waitlast() */ 895 } 896 897 xp->u.shf = shf; 898 return XCOM; 899 } 900 901 /* 902 * perform #pattern and %pattern substitution in ${} 903 */ 904 905 static char * 906 trimsub(str, pat, how) 907 register char *str; 908 char *pat; 909 int how; 910 { 911 register char *end = strchr(str, 0); 912 register char *p, c; 913 914 switch (how&0xff) { /* UCHAR_MAX maybe? */ 915 case '#': /* shortest at beginning */ 916 for (p = str; p <= end; p++) { 917 c = *p; *p = '\0'; 918 if (gmatch(str, pat, FALSE)) { 919 *p = c; 920 return p; 921 } 922 *p = c; 923 } 924 break; 925 case '#'|0x80: /* longest match at beginning */ 926 for (p = end; p >= str; p--) { 927 c = *p; *p = '\0'; 928 if (gmatch(str, pat, FALSE)) { 929 *p = c; 930 return p; 931 } 932 *p = c; 933 } 934 break; 935 case '%': /* shortest match at end */ 936 for (p = end; p >= str; p--) { 937 if (gmatch(p, pat, FALSE)) 938 return str_nsave(str, p - str, ATEMP); 939 } 940 break; 941 case '%'|0x80: /* longest match at end */ 942 for (p = str; p <= end; p++) { 943 if (gmatch(p, pat, FALSE)) 944 return str_nsave(str, p - str, ATEMP); 945 } 946 break; 947 } 948 949 return str; /* no match, return string */ 950 } 951 952 /* 953 * glob 954 * Name derived from V6's /etc/glob, the program that expanded filenames. 955 */ 956 957 /* XXX cp not const 'cause slashes are temporarily replaced with nulls... */ 958 static void 959 glob(cp, wp, markdirs) 960 char *cp; 961 register XPtrV *wp; 962 int markdirs; 963 { 964 int oldsize = XPsize(*wp); 965 966 if (glob_str(cp, wp, markdirs) == 0) 967 XPput(*wp, debunk(cp, cp, strlen(cp) + 1)); 968 else 969 qsortp(XPptrv(*wp) + oldsize, (size_t)(XPsize(*wp) - oldsize), 970 xstrcmp); 971 } 972 973 #define GF_NONE 0 974 #define GF_EXCHECK BIT(0) /* do existence check on file */ 975 #define GF_GLOBBED BIT(1) /* some globbing has been done */ 976 #define GF_MARKDIR BIT(2) /* add trailing / to directories */ 977 978 /* Apply file globbing to cp and store the matching files in wp. Returns 979 * the number of matches found. 980 */ 981 int 982 glob_str(cp, wp, markdirs) 983 char *cp; 984 XPtrV *wp; 985 int markdirs; 986 { 987 int oldsize = XPsize(*wp); 988 XString xs; 989 char *xp; 990 991 Xinit(xs, xp, 256, ATEMP); 992 globit(&xs, &xp, cp, wp, markdirs ? GF_MARKDIR : GF_NONE); 993 Xfree(xs, xp); 994 995 return XPsize(*wp) - oldsize; 996 } 997 998 static void 999 globit(xs, xpp, sp, wp, check) 1000 XString *xs; /* dest string */ 1001 char **xpp; /* ptr to dest end */ 1002 char *sp; /* source path */ 1003 register XPtrV *wp; /* output list */ 1004 int check; /* GF_* flags */ 1005 { 1006 register char *np; /* next source component */ 1007 char *xp = *xpp; 1008 char *se; 1009 char odirsep; 1010 1011 /* This to allow long expansions to be interrupted */ 1012 intrcheck(); 1013 1014 if (sp == NULL) { /* end of source path */ 1015 /* We only need to check if the file exists if a pattern 1016 * is followed by a non-pattern (eg, foo*x/bar; no check 1017 * is needed for foo* since the match must exist) or if 1018 * any patterns were expanded and the markdirs option is set. 1019 * Symlinks make things a bit tricky... 1020 */ 1021 if ((check & GF_EXCHECK) 1022 || ((check & GF_MARKDIR) && (check & GF_GLOBBED))) 1023 { 1024 #define stat_check() (stat_done ? stat_done : \ 1025 (stat_done = stat(Xstring(*xs, xp), &statb) < 0 \ 1026 ? -1 : 1)) 1027 struct stat lstatb, statb; 1028 int stat_done = 0; /* -1: failed, 1 ok */ 1029 1030 if (lstat(Xstring(*xs, xp), &lstatb) < 0) 1031 return; 1032 /* special case for systems which strip trailing 1033 * slashes from regular files (eg, /etc/passwd/). 1034 * SunOS 4.1.3 does this... 1035 */ 1036 if ((check & GF_EXCHECK) && xp > Xstring(*xs, xp) 1037 && ISDIRSEP(xp[-1]) && !S_ISDIR(lstatb.st_mode) 1038 #ifdef S_ISLNK 1039 && (!S_ISLNK(lstatb.st_mode) 1040 || stat_check() < 0 1041 || !S_ISDIR(statb.st_mode)) 1042 #endif /* S_ISLNK */ 1043 ) 1044 return; 1045 /* Possibly tack on a trailing / if there isn't already 1046 * one and if the file is a directory or a symlink to a 1047 * directory 1048 */ 1049 if (((check & GF_MARKDIR) && (check & GF_GLOBBED)) 1050 && xp > Xstring(*xs, xp) && !ISDIRSEP(xp[-1]) 1051 && (S_ISDIR(lstatb.st_mode) 1052 #ifdef S_ISLNK 1053 || (S_ISLNK(lstatb.st_mode) 1054 && stat_check() > 0 1055 && S_ISDIR(statb.st_mode)) 1056 #endif /* S_ISLNK */ 1057 )) 1058 { 1059 *xp++ = DIRSEP; 1060 *xp = '\0'; 1061 } 1062 } 1063 #ifdef OS2 /* Done this way to avoid bug in gcc 2.7.2... */ 1064 /* Ugly kludge required for command 1065 * completion - see how search_access() 1066 * is implemented for OS/2... 1067 */ 1068 # define KLUDGE_VAL 4 1069 #else /* OS2 */ 1070 # define KLUDGE_VAL 0 1071 #endif /* OS2 */ 1072 XPput(*wp, str_nsave(Xstring(*xs, xp), Xlength(*xs, xp) 1073 + KLUDGE_VAL, ATEMP)); 1074 return; 1075 } 1076 1077 if (xp > Xstring(*xs, xp)) 1078 *xp++ = DIRSEP; 1079 while (ISDIRSEP(*sp)) { 1080 Xcheck(*xs, xp); 1081 *xp++ = *sp++; 1082 } 1083 np = ksh_strchr_dirsep(sp); 1084 if (np != NULL) { 1085 se = np; 1086 odirsep = *np; /* don't assume DIRSEP, can be multiple kinds */ 1087 *np++ = '\0'; 1088 } else { 1089 odirsep = '\0'; /* keep gcc quiet */ 1090 se = sp + strlen(sp); 1091 } 1092 1093 1094 /* Check if sp needs globbing - done to avoid pattern checks for strings 1095 * containing MAGIC characters, open ['s without the matching close ], 1096 * etc. (otherwise opendir() will be called which may fail because the 1097 * directory isn't readable - if no globbing is needed, only execute 1098 * permission should be required (as per POSIX)). 1099 */ 1100 if (!has_globbing(sp, se)) { 1101 XcheckN(*xs, xp, se - sp + 1); 1102 debunk(xp, sp, Xnleft(*xs, xp)); 1103 xp += strlen(xp); 1104 *xpp = xp; 1105 globit(xs, xpp, np, wp, check); 1106 } else { 1107 DIR *dirp; 1108 struct dirent *d; 1109 char *name; 1110 int len; 1111 int prefix_len; 1112 1113 /* xp = *xpp; copy_non_glob() may have re-alloc'd xs */ 1114 *xp = '\0'; 1115 prefix_len = Xlength(*xs, xp); 1116 dirp = ksh_opendir(prefix_len ? Xstring(*xs, xp) : "."); 1117 if (dirp == NULL) 1118 goto Nodir; 1119 while ((d = readdir(dirp)) != NULL) { 1120 name = d->d_name; 1121 if ((*name == '.' && *sp != '.') 1122 || !gmatch(name, sp, TRUE)) 1123 continue; 1124 1125 len = NLENGTH(d) + 1; 1126 XcheckN(*xs, xp, len); 1127 memcpy(xp, name, len); 1128 *xpp = xp + len - 1; 1129 globit(xs, xpp, np, wp, 1130 (check & GF_MARKDIR) | GF_GLOBBED 1131 | (np ? GF_EXCHECK : GF_NONE)); 1132 xp = Xstring(*xs, xp) + prefix_len; 1133 } 1134 closedir(dirp); 1135 Nodir:; 1136 } 1137 1138 if (np != NULL) 1139 *--np = odirsep; 1140 } 1141 1142 #if 0 1143 /* Check if p contains something that needs globbing; if it does, 0 is 1144 * returned; if not, p is copied into xs/xp after stripping any MAGICs 1145 */ 1146 static int copy_non_glob ARGS((XString *xs, char **xpp, char *p)); 1147 static int 1148 copy_non_glob(xs, xpp, p) 1149 XString *xs; 1150 char **xpp; 1151 char *p; 1152 { 1153 char *xp; 1154 int len = strlen(p); 1155 1156 XcheckN(*xs, *xpp, len); 1157 xp = *xpp; 1158 for (; *p; p++) { 1159 if (ISMAGIC(*p)) { 1160 int c = *++p; 1161 1162 if (c == '*' || c == '?') 1163 return 0; 1164 if (*p == '[') { 1165 char *q = p + 1; 1166 1167 if (ISMAGIC(*q) && q[1] == NOT) 1168 q += 2; 1169 if (ISMAGIC(*q) && q[1] == ']') 1170 q += 2; 1171 for (; *q; q++) 1172 if (ISMAGIC(*q) && *++q == ']') 1173 return 0; 1174 /* pass a literal [ through */ 1175 } 1176 /* must be a MAGIC-MAGIC, or MAGIC-!, MAGIC--, etc. */ 1177 } 1178 *xp++ = *p; 1179 } 1180 *xp = '\0'; 1181 *xpp = xp; 1182 return 1; 1183 } 1184 #endif /* 0 */ 1185 1186 /* remove MAGIC from string */ 1187 char * 1188 debunk(dp, sp, dlen) 1189 char *dp; 1190 const char *sp; 1191 size_t dlen; 1192 { 1193 char *d, *s; 1194 1195 if ((s = strchr(sp, MAGIC))) { 1196 if (s - sp >= (ptrdiff_t)dlen) 1197 return dp; 1198 memcpy(dp, sp, s - sp); 1199 for (d = dp + (s - sp); *s && (d - dp < (ptrdiff_t)dlen); s++) 1200 if (!ISMAGIC(*s) || !(*++s & 0x80) 1201 || !strchr("*+?@! ", *s & 0x7f)) 1202 *d++ = *s; 1203 else { 1204 /* extended pattern operators: *+?@! */ 1205 if ((*s & 0x7f) != ' ') 1206 *d++ = *s & 0x7f; 1207 if (d - dp < (ptrdiff_t)dlen) 1208 *d++ = '('; 1209 } 1210 *d = '\0'; 1211 } else if (dp != sp) 1212 strlcpy(dp, sp, dlen); 1213 return dp; 1214 } 1215 1216 /* Check if p is an unquoted name, possibly followed by a / or :. If so 1217 * puts the expanded version in *dcp,dp and returns a pointer in p just 1218 * past the name, otherwise returns 0. 1219 */ 1220 static char * 1221 maybe_expand_tilde(p, dsp, dpp, isassign) 1222 char *p; 1223 XString *dsp; 1224 char **dpp; 1225 int isassign; 1226 { 1227 XString ts; 1228 char *dp = *dpp; 1229 char *tp, *r; 1230 1231 Xinit(ts, tp, 16, ATEMP); 1232 /* : only for DOASNTILDE form */ 1233 while (p[0] == CHAR && !ISDIRSEP(p[1]) 1234 && (!isassign || p[1] != PATHSEP)) 1235 { 1236 Xcheck(ts, tp); 1237 *tp++ = p[1]; 1238 p += 2; 1239 } 1240 *tp = '\0'; 1241 r = (p[0] == EOS || p[0] == CHAR || p[0] == CSUBST) ? tilde(Xstring(ts, tp)) : (char *) 0; 1242 Xfree(ts, tp); 1243 if (r) { 1244 while (*r) { 1245 Xcheck(*dsp, dp); 1246 if (ISMAGIC(*r)) 1247 *dp++ = MAGIC; 1248 *dp++ = *r++; 1249 } 1250 *dpp = dp; 1251 r = p; 1252 } 1253 return r; 1254 } 1255 1256 /* 1257 * tilde expansion 1258 * 1259 * based on a version by Arnold Robbins 1260 */ 1261 1262 static char * 1263 tilde(cp) 1264 char *cp; 1265 { 1266 char *dp; 1267 1268 if (cp[0] == '\0') 1269 dp = str_val(global("HOME")); 1270 else if (cp[0] == '+' && cp[1] == '\0') 1271 dp = str_val(global("PWD")); 1272 else if (cp[0] == '-' && cp[1] == '\0') 1273 dp = str_val(global("OLDPWD")); 1274 else 1275 dp = homedir(cp); 1276 /* If HOME, PWD or OLDPWD are not set, don't expand ~ */ 1277 if (dp == null) 1278 dp = (char *) 0; 1279 return dp; 1280 } 1281 1282 /* 1283 * map userid to user's home directory. 1284 * note that 4.3's getpw adds more than 6K to the shell, 1285 * and the YP version probably adds much more. 1286 * we might consider our own version of getpwnam() to keep the size down. 1287 */ 1288 1289 static char * 1290 homedir(name) 1291 char *name; 1292 { 1293 register struct tbl *ap; 1294 1295 ap = tenter(&homedirs, name, hash(name)); 1296 if (!(ap->flag & ISSET)) { 1297 #ifdef OS2 1298 /* No usernames in OS2 - punt */ 1299 return NULL; 1300 #else /* OS2 */ 1301 struct passwd *pw; 1302 size_t n; 1303 1304 pw = getpwnam(name); 1305 if (pw == NULL) 1306 return NULL; 1307 n = strlen(pw->pw_dir); 1308 if (n > 0 && '/' != pw->pw_dir[n - 1]) { 1309 ap->val.s = str_nsave(pw->pw_dir, n + 1, APERM); 1310 ap->val.s[n] = '/'; 1311 ap->val.s[n + 1] = '\0'; 1312 } else { 1313 ap->val.s = str_save(pw->pw_dir, APERM); 1314 } 1315 ap->flag |= DEFINED|ISSET|ALLOC; 1316 #endif /* OS2 */ 1317 } 1318 return ap->val.s; 1319 } 1320 1321 #ifdef BRACE_EXPAND 1322 static void 1323 alt_expand(wp, start, exp_start, end, fdo) 1324 XPtrV *wp; 1325 char *start, *exp_start; 1326 char *end; 1327 int fdo; 1328 { 1329 int UNINITIALIZED(count); 1330 char *brace_start, *brace_end, *UNINITIALIZED(comma); 1331 char *field_start; 1332 char *p; 1333 1334 /* search for open brace */ 1335 for (p = exp_start; (p = strchr(p, MAGIC)) && p[1] != OBRACE; p += 2) 1336 ; 1337 brace_start = p; 1338 1339 /* find matching close brace, if any */ 1340 if (p) { 1341 comma = (char *) 0; 1342 count = 1; 1343 for (p += 2; *p && count; p++) { 1344 if (ISMAGIC(*p)) { 1345 if (*++p == OBRACE) 1346 count++; 1347 else if (*p == CBRACE) 1348 --count; 1349 else if (*p == ',' && count == 1) 1350 comma = p; 1351 } 1352 } 1353 } 1354 /* no valid expansions... */ 1355 if (!p || count != 0) { 1356 /* Note that given a{{b,c} we do not expand anything (this is 1357 * what at&t ksh does. This may be changed to do the {b,c} 1358 * expansion. } 1359 */ 1360 if (fdo & DOGLOB) 1361 glob(start, wp, fdo & DOMARKDIRS); 1362 else 1363 XPput(*wp, debunk(start, start, end - start)); 1364 return; 1365 } 1366 brace_end = p; 1367 if (!comma) { 1368 alt_expand(wp, start, brace_end, end, fdo); 1369 return; 1370 } 1371 1372 /* expand expression */ 1373 field_start = brace_start + 2; 1374 count = 1; 1375 for (p = brace_start + 2; p != brace_end; p++) { 1376 if (ISMAGIC(*p)) { 1377 if (*++p == OBRACE) 1378 count++; 1379 else if ((*p == CBRACE && --count == 0) 1380 || (*p == ',' && count == 1)) 1381 { 1382 char *new; 1383 int l1, l2, l3; 1384 1385 l1 = brace_start - start; 1386 l2 = (p - 1) - field_start; 1387 l3 = end - brace_end; 1388 new = (char *) alloc(l1 + l2 + l3 + 1, ATEMP); 1389 memcpy(new, start, l1); 1390 memcpy(new + l1, field_start, l2); 1391 memcpy(new + l1 + l2, brace_end, l3); 1392 new[l1 + l2 + l3] = '\0'; 1393 alt_expand(wp, new, new + l1, 1394 new + l1 + l2 + l3, fdo); 1395 field_start = p + 1; 1396 } 1397 } 1398 } 1399 return; 1400 } 1401 #endif /* BRACE_EXPAND */ 1402