usr/src/cmd/csh/sh.exp.c

   1 /*
   2  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
   3  * Use is subject to license terms.
   4  */
   5
   6 /*      Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T     */
   7 /*        All Rights Reserved   */
   8
   9 /*
  10  * Copyright (c) 1980 Regents of the University of California.
  11  * All rights reserved.  The Berkeley Software License Agreement
  12  * specifies the terms and conditions for redistribution.
  13  */
  14
  15 #pragma ident   "%Z%%M% %I%     %E% SMI"
  16
  17 #include "sh.h"
  18 #include "sh.tconst.h"
  19
  20 /*
  21  * C shell
  22  */
  23
  24 #define IGNORE  1       /* in ignore, it means to ignore value, just parse */
  25 #define NOGLOB  2       /* in ignore, it means not to globone */
  26
  27 #define ADDOP   1
  28 #define MULOP   2
  29 #define EQOP    4
  30 #define RELOP   8
  31 #define RESTOP  16
  32 #define ANYOP   31
  33
  34 #define EQEQ    1
  35 #define GTR     2
  36 #define LSS     4
  37 #define NOTEQ   6
  38 #define EQMATCH 7
  39 #define NOTEQMATCH 8
  40
  41 int     exp0(tchar ***, bool);
  42 int     exp1(tchar ***, bool);
  43 int     exp2(tchar ***, bool);
  44 int     exp2a(tchar ***, bool);
  45 int     exp2b(tchar ***, bool);
  46 int     exp2c(tchar ***, bool);
  47 tchar   *exp3(tchar ***, bool);
  48 tchar   *exp3a(tchar ***, bool);
  49 tchar   *exp4(tchar ***, bool);
  50 tchar   *exp5(tchar ***, bool);
  51 tchar   *exp6(tchar ***, bool);
  52 void    evalav(tchar **);
  53
  54 /*
  55  * Determine if file given by name is accessible with permissions
  56  * given by mode.
  57  *
  58  * Borrowed from the Bourne sh, and modified a bit
  59  *
  60  * If the requested access  is  permitted,  a  value  of  0  is
  61  * returned.  Otherwise, a value of -1 is returned and errno is
  62  * set to indicate the error
  63  */
  64
  65 int
  66 chk_access(tchar *path, mode_t mode)
  67 {
  68         static int flag;
  69         static uid_t euid;
  70         struct stat statb;
  71         mode_t ftype;
  72         unsigned char name[MAXPATHLEN*MB_LEN_MAX]; /* General use buffer. */
  73
  74         /* convert tchar * to char * */
  75         tstostr(name, path);
  76
  77         if (flag == 0) {
  78                 euid = geteuid();
  79                 flag = 1;
  80         }
  81         if (stat((char *)name, &statb) == 0) {
  82                 ftype = statb.st_mode & S_IFMT;
  83                 if (access((char *)name, 010|(mode>>6)) == 0) {
  84                         if (euid == 0) {
  85                                 if (ftype != S_IFREG || mode != S_IEXEC)
  86                                         return (0);
  87                                 /* root can execute file as long as it has execute
  88                                 permission for someone */
  89                                 if (statb.st_mode & (S_IEXEC|(S_IEXEC>>3)|(S_IEXEC>>6)))
  90                                         return (0);
  91                                 return (-1);
  92                         }
  93                         return (0);
  94                 }
  95         }
  96         return (-1);
  97 }
  98
  99 int
 100 exp(tchar ***vp)
 101 {
 102 #ifdef TRACE
 103         tprintf("TRACE- exp()\n");
 104 #endif
 105
 106         return (exp0(vp, 0));
 107 }
 108
 109 int
 110 exp0(tchar ***vp, bool ignore)
 111 {
 112         int p1 = exp1(vp, ignore);
 113 #ifdef TRACE
 114         tprintf("TRACE- exp0()\n");
 115 #endif
 116
 117 #ifdef EDEBUG
 118         etraci("exp0 p1", p1, vp);
 119 #endif
 120         if (**vp && eq(**vp, S_BARBAR /* "||" */)) {
 121                 int p2;
 122
 123                 (*vp)++;
 124                 p2 = exp0(vp, (ignore&IGNORE) || p1);
 125 #ifdef EDEBUG
 126                 etraci("exp0 p2", p2, vp);
 127 #endif
 128                 return (p1 || p2);
 129         }
 130         return (p1);
 131 }
 132
 133 int
 134 exp1(tchar ***vp, bool ignore)
 135 {
 136         int p1 = exp2(vp, ignore);
 137
 138 #ifdef TRACE
 139         tprintf("TRACE- exp1()\n");
 140 #endif
 141 #ifdef EDEBUG
 142         etraci("exp1 p1", p1, vp);
 143 #endif
 144         if (**vp && eq(**vp, S_ANDAND /* "&&" */)) {
 145                 int p2;
 146
 147                 (*vp)++;
 148                 p2 = exp1(vp, (ignore&IGNORE) || !p1);
 149 #ifdef EDEBUG
 150                 etraci("exp1 p2", p2, vp);
 151 #endif
 152                 return (p1 && p2);
 153         }
 154         return (p1);
 155 }
 156
 157 int
 158 exp2(tchar ***vp, bool ignore)
 159 {
 160         int p1 = exp2a(vp, ignore);
 161
 162 #ifdef TRACE
 163         tprintf("TRACE- exp2()\n");
 164 #endif
 165 #ifdef EDEBUG
 166         etraci("exp3 p1", p1, vp);
 167 #endif
 168         if (**vp && eq(**vp, S_BAR /* "|" */)) {
 169                 int p2;
 170
 171                 (*vp)++;
 172                 p2 = exp2(vp, ignore);
 173 #ifdef EDEBUG
 174                 etraci("exp3 p2", p2, vp);
 175 #endif
 176                 return (p1 | p2);
 177         }
 178         return (p1);
 179 }
 180
 181 int
 182 exp2a(tchar ***vp, bool ignore)
 183 {
 184         int p1 = exp2b(vp, ignore);
 185
 186 #ifdef TRACE
 187         tprintf("TRACE- exp2a()\n");
 188 #endif
 189 #ifdef EDEBUG
 190         etraci("exp2a p1", p1, vp);
 191 #endif
 192         if (**vp && eq(**vp, S_HAT /* "^" */)) {
 193                 int p2;
 194
 195                 (*vp)++;
 196                 p2 = exp2a(vp, ignore);
 197 #ifdef EDEBUG
 198                 etraci("exp2a p2", p2, vp);
 199 #endif
 200                 return (p1 ^ p2);
 201         }
 202         return (p1);
 203 }
 204
 205 int
 206 exp2b(tchar ***vp, bool ignore)
 207 {
 208         int p1 = exp2c(vp, ignore);
 209
 210 #ifdef TRACE
 211         tprintf("TRACE- exp2b()\n");
 212 #endif
 213 #ifdef EDEBUG
 214         etraci("exp2b p1", p1, vp);
 215 #endif
 216         if (**vp && eq(**vp, S_AND /* "&" */)) {
 217                 int p2;
 218
 219                 (*vp)++;
 220                 p2 = exp2b(vp, ignore);
 221 #ifdef EDEBUG
 222                 etraci("exp2b p2", p2, vp);
 223 #endif
 224                 return (p1 & p2);
 225         }
 226         return (p1);
 227 }
 228
 229 int
 230 exp2c(tchar ***vp, bool ignore)
 231 {
 232         tchar *p1 = exp3(vp, ignore);
 233         tchar *p2;
 234         int i;
 235
 236 #ifdef TRACE
 237         tprintf("TRACE- exp2c()\n");
 238 #endif
 239 #ifdef EDEBUG
 240         etracc("exp2c p1", p1, vp);
 241 #endif
 242         if (i = isa(**vp, EQOP)) {
 243                 (*vp)++;
 244                 if (i == EQMATCH || i == NOTEQMATCH)
 245                         ignore |= NOGLOB;
 246                 p2 = exp3(vp, ignore);
 247 #ifdef EDEBUG
 248                 etracc("exp2c p2", p2, vp);
 249 #endif
 250                 if (!(ignore&IGNORE)) switch (i) {
 251
 252                 case EQEQ:
 253                         i = eq(p1, p2);
 254                         break;
 255
 256                 case NOTEQ:
 257                         i = !eq(p1, p2);
 258                         break;
 259
 260                 case EQMATCH:
 261                         i = Gmatch(p1, p2);
 262                         break;
 263
 264                 case NOTEQMATCH:
 265                         i = !Gmatch(p1, p2);
 266                         break;
 267                 }
 268                 xfree(p1), xfree(p2);
 269                 return (i);
 270         }
 271         i = egetn(p1);
 272         xfree(p1);
 273         return (i);
 274 }
 275
 276 tchar *
 277 exp3(tchar ***vp, bool ignore)
 278 {
 279         tchar *p1, *p2;
 280         int i;
 281
 282 #ifdef TRACE
 283         tprintf("TRACE- exp3()\n");
 284 #endif
 285         p1 = exp3a(vp, ignore);
 286 #ifdef EDEBUG
 287         etracc("exp3 p1", p1, vp);
 288 #endif
 289         if (i = isa(**vp, RELOP)) {
 290                 (*vp)++;
 291                 if (**vp && eq(**vp, S_EQ /* "=" */))
 292                         i |= 1, (*vp)++;
 293                 p2 = exp3(vp, ignore);
 294 #ifdef EDEBUG
 295                 etracc("exp3 p2", p2, vp);
 296 #endif
 297                 if (!(ignore&IGNORE)) switch (i) {
 298
 299                 case GTR:
 300                         i = egetn(p1) > egetn(p2);
 301                         break;
 302
 303                 case GTR|1:
 304                         i = egetn(p1) >= egetn(p2);
 305                         break;
 306
 307                 case LSS:
 308                         i = egetn(p1) < egetn(p2);
 309                         break;
 310
 311                 case LSS|1:
 312                         i = egetn(p1) <= egetn(p2);
 313                         break;
 314                 }
 315                 xfree(p1), xfree(p2);
 316                 return (putn(i));
 317         }
 318         return (p1);
 319 }
 320
 321 tchar *
 322 exp3a(tchar ***vp, bool ignore)
 323 {
 324         tchar *p1, *p2, *op;
 325         int i;
 326
 327 #ifdef TRACE
 328         tprintf("TRACE- exp3a()\n");
 329 #endif
 330         p1 = exp4(vp, ignore);
 331 #ifdef EDEBUG
 332         etracc("exp3a p1", p1, vp);
 333 #endif
 334         op = **vp;
 335         /* if (op && any(op[0], "<>") && op[0] == op[1]) { */
 336         if (op && (op[0] == '<' || op[0] == '>') && op[0] == op[1]) {
 337                 (*vp)++;
 338                 p2 = exp3a(vp, ignore);
 339 #ifdef EDEBUG
 340                 etracc("exp3a p2", p2, vp);
 341 #endif
 342                 if (op[0] == '<')
 343                         i = egetn(p1) << egetn(p2);
 344                 else
 345                         i = egetn(p1) >> egetn(p2);
 346                 xfree(p1), xfree(p2);
 347                 return (putn(i));
 348         }
 349         return (p1);
 350 }
 351
 352 tchar *
 353 exp4(tchar ***vp, bool ignore)
 354 {
 355         tchar *p1, *p2;
 356         int i = 0;
 357
 358 #ifdef TRACE
 359         tprintf("TRACE- exp4()\n");
 360 #endif
 361         p1 = exp5(vp, ignore);
 362 #ifdef EDEBUG
 363         etracc("exp4 p1", p1, vp);
 364 #endif
 365         if (isa(**vp, ADDOP)) {
 366                 tchar *op = *(*vp)++;
 367
 368                 p2 = exp4(vp, ignore);
 369 #ifdef EDEBUG
 370                 etracc("exp4 p2", p2, vp);
 371 #endif
 372                 if (!(ignore&IGNORE)) switch (op[0]) {
 373
 374                 case '+':
 375                         i = egetn(p1) + egetn(p2);
 376                         break;
 377
 378                 case '-':
 379                         i = egetn(p1) - egetn(p2);
 380                         break;
 381                 }
 382                 xfree(p1), xfree(p2);
 383                 return (putn(i));
 384         }
 385         return (p1);
 386 }
 387
 388 tchar *
 389 exp5(tchar ***vp, bool ignore)
 390 {
 391         tchar *p1, *p2;
 392         int i = 0;
 393
 394 #ifdef TRACE
 395         tprintf("TRACE- exp5()\n");
 396 #endif
 397         p1 = exp6(vp, ignore);
 398 #ifdef EDEBUG
 399         etracc("exp5 p1", p1, vp);
 400 #endif
 401         if (isa(**vp, MULOP)) {
 402                 tchar *op = *(*vp)++;
 403
 404                 p2 = exp5(vp, ignore);
 405 #ifdef EDEBUG
 406                 etracc("exp5 p2", p2, vp);
 407 #endif
 408                 if (!(ignore&IGNORE)) switch (op[0]) {
 409
 410                 case '*':
 411                         i = egetn(p1) * egetn(p2);
 412                         break;
 413
 414                 case '/':
 415                         i = egetn(p2);
 416                         if (i == 0)
 417                                 error("Divide by 0");
 418                         i = egetn(p1) / i;
 419                         break;
 420
 421                 case '%':
 422                         i = egetn(p2);
 423                         if (i == 0)
 424                                 error("Mod by 0");
 425                         i = egetn(p1) % i;
 426                         break;
 427                 }
 428                 xfree(p1), xfree(p2);
 429                 return (putn(i));
 430         }
 431         return (p1);
 432 }
 433
 434 tchar *
 435 exp6(tchar ***vp, bool ignore)
 436 {
 437         int ccode, i;
 438         tchar *cp, *dp, *ep;
 439
 440 #ifdef TRACE
 441         tprintf("TRACE- exp6()\n");
 442 #endif
 443         if (**vp == 0)
 444                 bferr("Expression syntax");
 445         if (eq(**vp, S_EXAS /* "!" */)) {
 446                 (*vp)++;
 447                 cp = exp6(vp, ignore);
 448 #ifdef EDEBUG
 449                 etracc("exp6 ! cp", cp, vp);
 450 #endif
 451                 i = egetn(cp);
 452                 xfree(cp);
 453                 return (putn(!i));
 454         }
 455         if (eq(**vp, S_TIL /* "~" */)) {
 456                 (*vp)++;
 457                 cp = exp6(vp, ignore);
 458 #ifdef EDEBUG
 459                 etracc("exp6 ~ cp", cp, vp);
 460 #endif
 461                 i = egetn(cp);
 462                 xfree(cp);
 463                 return (putn(~i));
 464         }
 465         if (eq(**vp, S_LPAR /* "(" */)) {
 466                 (*vp)++;
 467                 ccode = exp0(vp, ignore);
 468 #ifdef EDEBUG
 469                 etraci("exp6 () ccode", ccode, vp);
 470 #endif
 471                 if (*vp == 0 || **vp == 0 || ***vp != ')')
 472                         bferr("Expression syntax");
 473                 (*vp)++;
 474                 return (putn(ccode));
 475         }
 476         if (eq(**vp, S_LBRA /* "{" */)) {
 477                 tchar **v;
 478                 struct command faket;
 479                 tchar *fakecom[2];
 480
 481                 faket.t_dtyp = TCOM;
 482                 faket.t_dflg = 0;
 483                 faket.t_dcar = faket.t_dcdr = faket.t_dspr = NULL;
 484                 faket.t_dcom = fakecom;
 485                 fakecom[0] = S_BRAPPPBRA /* "{ ... }" */;
 486                 fakecom[1] = NOSTR;
 487                 (*vp)++;
 488                 v = *vp;
 489                 for (;;) {
 490                         if (!**vp)
 491                                 bferr("Missing }");
 492                         if (eq(*(*vp)++, S_RBRA /* "}" */))
 493                                 break;
 494                 }
 495                 if (ignore&IGNORE)
 496                         return (S_ /* "" */);
 497                 psavejob();
 498                 if (pfork(&faket, -1) == 0) {
 499                         *--(*vp) = 0;
 500                         evalav(v);
 501                         exitstat();
 502                 }
 503                 pwait();
 504                 prestjob();
 505 #ifdef EDEBUG
 506                 etraci("exp6 {} status", egetn(value("status")), vp);
 507 #endif
 508                 return (putn(egetn(value(S_status /* "status" */)) == 0));
 509         }
 510         if (isa(**vp, ANYOP))
 511                 return (S_ /* "" */);
 512         cp = *(*vp)++;
 513         if (*cp == '-' && any(cp[1], S_erwxfdzo /* "erwxfdzo" */)) {
 514                 struct stat stb;
 515
 516                 if (cp[2] != '\0')
 517                         bferr("Malformed file inquiry");
 518
 519                 /*
 520                  * Detect missing file names by checking for operator
 521                  * in the file name position.  However, if an operator
 522                  * name appears there, we must make sure that there's
 523                  * no file by that name (e.g., "/") before announcing
 524                  * an error.  Even this check isn't quite right, since
 525                  * it doesn't take globbing into account.
 526                  */
 527                 if ((**vp == NULL) || isa(**vp, ANYOP) && stat_(**vp, &stb))
 528                         bferr("Missing file name");
 529                 dp = *(*vp)++;
 530
 531                 if (ignore&IGNORE)
 532                         return (S_ /* "" */);
 533                 ep = globone(dp);
 534                 switch (cp[1]) {
 535
 536                 case 'r':
 537                         i = !chk_access(ep, S_IREAD);
 538                         break;
 539
 540                 case 'w':
 541                         i = !chk_access(ep, S_IWRITE);
 542                         break;
 543
 544                 case 'x':
 545                         i = !chk_access(ep, S_IEXEC);
 546                         break;
 547
 548                 default:
 549                         if (stat_(ep, &stb)) {
 550                                 xfree(ep);
 551                                 return (S_0 /* "0" */);
 552                         }
 553                         switch (cp[1]) {
 554
 555                         case 'f':
 556                                 i = (stb.st_mode & S_IFMT) == S_IFREG;
 557                                 break;
 558
 559                         case 'd':
 560                                 i = (stb.st_mode & S_IFMT) == S_IFDIR;
 561                                 break;
 562
 563                         case 'z':
 564                                 i = stb.st_size == 0;
 565                                 break;
 566
 567                         case 'e':
 568                                 i = 1;
 569                                 break;
 570
 571                         case 'o':
 572                                 i = stb.st_uid == uid;
 573                                 break;
 574                         }
 575                 }
 576 #ifdef EDEBUG
 577                 etraci("exp6 -? i", i, vp);
 578 #endif
 579                 xfree(ep);
 580                 return (putn(i));
 581         }
 582 #ifdef EDEBUG
 583         etracc("exp6 default", cp, vp);
 584 #endif
 585         return (ignore&NOGLOB ? savestr(cp) : globone(cp));
 586 }
 587
 588 void
 589 evalav(tchar **v)
 590 {
 591         struct wordent paraml;
 592         struct wordent *hp = &paraml;
 593         struct command *t;
 594         struct wordent *wdp = hp;
 595
 596 #ifdef TRACE
 597         tprintf("TRACE- evalav()\n");
 598 #endif
 599         set(S_status /* "status" */, S_0 /* "0" */);
 600         hp->prev = hp->next = hp;
 601         hp->word = S_ /* "" */;
 602         while (*v) {
 603                 struct wordent *new = (struct wordent *)xcalloc(1, sizeof *wdp);
 604
 605                 new->prev = wdp;
 606                 new->next = hp;
 607                 wdp->next = new;
 608                 wdp = new;
 609                 wdp->word = savestr(*v++);
 610         }
 611         hp->prev = wdp;
 612         alias(&paraml);
 613         t = syntax(paraml.next, &paraml, 0);
 614         if (err)
 615                 error("%s", gettext(err));
 616         execute(t, -1);
 617         freelex(&paraml), freesyn(t);
 618 }
 619
 620 int
 621 isa(tchar *cp, int what)
 622 {
 623
 624 #ifdef TRACE
 625         tprintf("TRACE- isa()\n");
 626 #endif
 627         if (cp == 0)
 628                 return ((what & RESTOP) != 0);
 629         if (cp[1] == 0) {
 630                 if (what & ADDOP && (*cp == '+' || *cp == '-'))
 631                         return (1);
 632                 if (what & MULOP && (*cp == '*' || *cp == '/' || *cp == '%'))
 633                         return (1);
 634                 if (what & RESTOP && (*cp == '(' || *cp == ')' || *cp == '!' ||
 635                                         *cp == '~' || *cp == '^' || *cp == '"'))
 636                         return (1);
 637         } else if (cp[2] == 0) {
 638                 if (what & RESTOP) {
 639                         if (cp[0] == '|' && cp[1] == '&')
 640                                 return (1);
 641                         if (cp[0] == '<' && cp[1] == '<')
 642                                 return (1);
 643                         if (cp[0] == '>' && cp[1] == '>')
 644                                 return (1);
 645                 }
 646                 if (what & EQOP) {
 647                         if (cp[0] == '=') {
 648                                 if (cp[1] == '=')
 649                                         return (EQEQ);
 650                                 if (cp[1] == '~')
 651                                         return (EQMATCH);
 652                         } else if (cp[0] == '!') {
 653                                 if (cp[1] == '=')
 654                                         return (NOTEQ);
 655                                 if (cp[1] == '~')
 656                                         return (NOTEQMATCH);
 657                         }
 658                 }
 659         }
 660         if (what & RELOP) {
 661                 if (*cp == '<')
 662                         return (LSS);
 663                 if (*cp == '>')
 664                         return (GTR);
 665         }
 666         return (0);
 667 }
 668
 669 int
 670 egetn(tchar *cp)
 671 {
 672
 673 #ifdef TRACE
 674         tprintf("TRACE- egetn()\n");
 675 #endif
 676         if (*cp && *cp != '-' && !digit(*cp))
 677                 bferr("Expression syntax");
 678         return (getn(cp));
 679 }
 680
 681 /* Phew! */
 682
 683 #ifdef EDEBUG
 684 void
 685 etraci(tchar *str, int i, tchar ***vp)
 686 {
 687
 688         printf("%s=%d\t", str, i);
 689         blkpr(*vp);
 690         printf("\n");
 691 }
 692
 693 void
 694 etracc(tchar *str, tchar *cp, tchar ***vp)
 695 {
 696
 697         printf("%s=%s\t", str, cp);
 698         blkpr(*vp);
 699         printf("\n");
 700 }
 701 #endif