contrib/tcsh/sh.exec.c

   1 /* $Header: /src/pub/tcsh/sh.exec.c,v 3.56 2002/06/25 19:02:11 christos Exp $ */
   2 /*
   3  * sh.exec.c: Search, find, and execute a command!
   4  */
   5 /*-
   6  * Copyright (c) 1980, 1991 The Regents of the University of California.
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33 #include "sh.h"
  34
  35 RCSID("$Id: sh.exec.c,v 3.56 2002/06/25 19:02:11 christos Exp $")
  36
  37 #include "tc.h"
  38 #include "tw.h"
  39 #ifdef WINNT_NATIVE
  40 #include <nt.const.h>
  41 #endif /*WINNT_NATIVE*/
  42
  43 /*
  44  * C shell
  45  */
  46
  47 #ifndef OLDHASH
  48 # define FASTHASH       /* Fast hashing is the default */
  49 #endif /* OLDHASH */
  50
  51 /*
  52  * System level search and execute of a command.
  53  * We look in each directory for the specified command name.
  54  * If the name contains a '/' then we execute only the full path name.
  55  * If there is no search path then we execute only full path names.
  56  */
  57
  58 /*
  59  * As we search for the command we note the first non-trivial error
  60  * message for presentation to the user.  This allows us often
  61  * to show that a file has the wrong mode/no access when the file
  62  * is not in the last component of the search path, so we must
  63  * go on after first detecting the error.
  64  */
  65 static char *exerr;             /* Execution error message */
  66 static Char *expath;            /* Path for exerr */
  67
  68 /*
  69  * The two part hash function is designed to let texec() call the
  70  * more expensive hashname() only once and the simple hash() several
  71  * times (once for each path component checked).
  72  * Byte size is assumed to be 8.
  73  */
  74 #define BITS_PER_BYTE   8
  75
  76 #ifdef FASTHASH
  77 /*
  78  * xhash is an array of hash buckets which are used to hash execs.  If
  79  * it is allocated (havhash true), then to tell if ``name'' is
  80  * (possibly) presend in the i'th component of the variable path, look
  81  * at the [hashname(name)] bucket of size [hashwidth] bytes, in the [i
  82  * mod size*8]'th bit.  The cache size is defaults to a length of 1024
  83  * buckets, each 1 byte wide.  This implementation guarantees that
  84  * objects n bytes wide will be aligned on n byte boundaries.
  85  */
  86 # define HSHMUL         241
  87
  88 static unsigned long *xhash = NULL;
  89 static unsigned int hashlength = 0, uhashlength = 0;
  90 static unsigned int hashwidth = 0, uhashwidth = 0;
  91 static int hashdebug = 0;
  92
  93 # define hash(a, b)     (((a) * HSHMUL + (b)) % (hashlength))
  94 # define widthof(t)     (sizeof(t) * BITS_PER_BYTE)
  95 # define tbit(f, i, t)  (((t *) xhash)[(f)] &  \
  96                          (1L << (i & (widthof(t) - 1))))
  97 # define tbis(f, i, t)  (((t *) xhash)[(f)] |= \
  98                          (1L << (i & (widthof(t) - 1))))
  99 # define cbit(f, i)     tbit(f, i, unsigned char)
 100 # define cbis(f, i)     tbis(f, i, unsigned char)
 101 # define sbit(f, i)     tbit(f, i, unsigned short)
 102 # define sbis(f, i)     tbis(f, i, unsigned short)
 103 # define ibit(f, i)     tbit(f, i, unsigned int)
 104 # define ibis(f, i)     tbis(f, i, unsigned int)
 105 # define lbit(f, i)     tbit(f, i, unsigned long)
 106 # define lbis(f, i)     tbis(f, i, unsigned long)
 107
 108 # define bit(f, i) (hashwidth==sizeof(unsigned char)  ? cbit(f,i) : \
 109                     ((hashwidth==sizeof(unsigned short) ? sbit(f,i) : \
 110                      ((hashwidth==sizeof(unsigned int)   ? ibit(f,i) : \
 111                      lbit(f,i))))))
 112 # define bis(f, i) (hashwidth==sizeof(unsigned char)  ? cbis(f,i) : \
 113                     ((hashwidth==sizeof(unsigned short) ? sbis(f,i) : \
 114                      ((hashwidth==sizeof(unsigned int)   ? ibis(f,i) : \
 115                      lbis(f,i))))))
 116 #else /* OLDHASH */
 117 /*
 118  * Xhash is an array of HSHSIZ bits (HSHSIZ / 8 chars), which are used
 119  * to hash execs.  If it is allocated (havhash true), then to tell
 120  * whether ``name'' is (possibly) present in the i'th component
 121  * of the variable path, you look at the bit in xhash indexed by
 122  * hash(hashname("name"), i).  This is setup automatically
 123  * after .login is executed, and recomputed whenever ``path'' is
 124  * changed.
 125  */
 126 # define HSHSIZ         8192    /* 1k bytes */
 127 # define HSHMASK                (HSHSIZ - 1)
 128 # define HSHMUL         243
 129 static char xhash[HSHSIZ / BITS_PER_BYTE];
 130
 131 # define hash(a, b)     (((a) * HSHMUL + (b)) & HSHMASK)
 132 # define bit(h, b)      ((h)[(b) >> 3] & 1 << ((b) & 7))        /* bit test */
 133 # define bis(h, b)      ((h)[(b) >> 3] |= 1 << ((b) & 7))       /* bit set */
 134
 135 #endif /* FASTHASH */
 136
 137 #ifdef VFORK
 138 static int hits, misses;
 139 #endif /* VFORK */
 140
 141 /* Dummy search path for just absolute search when no path */
 142 static Char *justabs[] = {STRNULL, 0};
 143
 144 static  void    pexerr          __P((void));
 145 static  void    texec           __P((Char *, Char **));
 146 int     hashname        __P((Char *));
 147 static  int     iscommand       __P((Char *));
 148
 149 void
 150 doexec(t, do_glob)
 151     register struct command *t;
 152     bool do_glob;
 153 {
 154     Char *dp, **pv, **av, *sav;
 155     struct varent *v;
 156     bool slash;
 157     int hashval, i;
 158     Char   *blk[2];
 159
 160     /*
 161      * Glob the command name. We will search $path even if this does something,
 162      * as in sh but not in csh.  One special case: if there is no PATH, then we
 163      * execute only commands which start with '/'.
 164      */
 165     blk[0] = t->t_dcom[0];
 166     blk[1] = 0;
 167     gflag = 0;
 168     if (do_glob)
 169         tglob(blk);
 170     if (gflag) {
 171         pv = globall(blk);
 172         if (pv == 0) {
 173             setname(short2str(blk[0]));
 174             stderror(ERR_NAME | ERR_NOMATCH);
 175         }
 176         gargv = 0;
 177     }
 178     else
 179         pv = saveblk(blk);
 180
 181     trim(pv);
 182
 183     exerr = 0;
 184     expath = Strsave(pv[0]);
 185 #ifdef VFORK
 186     Vexpath = expath;
 187 #endif /* VFORK */
 188
 189     v = adrof(STRpath);
 190     if (v == 0 && expath[0] != '/' && expath[0] != '.') {
 191         blkfree(pv);
 192         pexerr();
 193     }
 194     slash = any(short2str(expath), '/');
 195
 196     /*
 197      * Glob the argument list, if necessary. Otherwise trim off the quote bits.
 198      */
 199     gflag = 0;
 200     av = &t->t_dcom[1];
 201     if (do_glob)
 202         tglob(av);
 203     if (gflag) {
 204         av = globall(av);
 205         if (av == 0) {
 206             blkfree(pv);
 207             setname(short2str(expath));
 208             stderror(ERR_NAME | ERR_NOMATCH);
 209         }
 210         gargv = 0;
 211     }
 212     else
 213         av = saveblk(av);
 214
 215     blkfree(t->t_dcom);
 216     t->t_dcom = blkspl(pv, av);
 217     xfree((ptr_t) pv);
 218     xfree((ptr_t) av);
 219     av = t->t_dcom;
 220     trim(av);
 221
 222     if (*av == NULL || **av == '\0')
 223         pexerr();
 224
 225     xechoit(av);                /* Echo command if -x */
 226 #ifdef CLOSE_ON_EXEC
 227     /*
 228      * Since all internal file descriptors are set to close on exec, we don't
 229      * need to close them explicitly here.  Just reorient ourselves for error
 230      * messages.
 231      */
 232     SHIN = 0;
 233     SHOUT = 1;
 234     SHDIAG = 2;
 235     OLDSTD = 0;
 236     isoutatty = isatty(SHOUT);
 237     isdiagatty = isatty(SHDIAG);
 238 #else
 239     closech();                  /* Close random fd's */
 240 #endif
 241     /*
 242      * We must do this AFTER any possible forking (like `foo` in glob) so that
 243      * this shell can still do subprocesses.
 244      */
 245 #ifdef BSDSIGS
 246     (void) sigsetmask((sigmask_t) 0);
 247 #else /* BSDSIGS */
 248     (void) sigrelse(SIGINT);
 249     (void) sigrelse(SIGCHLD);
 250 #endif /* BSDSIGS */
 251
 252     /*
 253      * If no path, no words in path, or a / in the filename then restrict the
 254      * command search.
 255      */
 256     if (v == NULL || v->vec == NULL || v->vec[0] == NULL || slash)
 257         pv = justabs;
 258     else
 259         pv = v->vec;
 260     sav = Strspl(STRslash, *av);/* / command name for postpending */
 261 #ifdef VFORK
 262     Vsav = sav;
 263 #endif /* VFORK */
 264     hashval = havhash ? hashname(*av) : 0;
 265
 266     i = 0;
 267 #ifdef VFORK
 268     hits++;
 269 #endif /* VFORK */
 270     do {
 271         /*
 272          * Try to save time by looking at the hash table for where this command
 273          * could be.  If we are doing delayed hashing, then we put the names in
 274          * one at a time, as the user enters them.  This is kinda like Korn
 275          * Shell's "tracked aliases".
 276          */
 277         if (!slash && ABSOLUTEP(pv[0]) && havhash) {
 278 #ifdef FASTHASH
 279             if (!bit(hashval, i))
 280                 goto cont;
 281 #else /* OLDHASH */
 282             int hashval1 = hash(hashval, i);
 283             if (!bit(xhash, hashval1))
 284                 goto cont;
 285 #endif /* FASTHASH */
 286         }
 287         if (pv[0][0] == 0 || eq(pv[0], STRdot)) /* don't make ./xxx */
 288         {
 289
 290 #ifdef COHERENT
 291             if (t->t_dflg & F_AMPERSAND) {
 292 # ifdef JOBDEBUG
 293                 xprintf("set SIGINT to SIG_IGN\n");
 294                 xprintf("set SIGQUIT to SIG_DFL\n");
 295 # endif /* JOBDEBUG */
 296                 (void) signal(SIGINT,SIG_IGN); /* may not be necessary */
 297                 (void) signal(SIGQUIT,SIG_DFL);
 298             }
 299
 300             if (gointr && eq(gointr, STRminus)) {
 301 # ifdef JOBDEBUG
 302                 xprintf("set SIGINT to SIG_IGN\n");
 303                 xprintf("set SIGQUIT to SIG_IGN\n");
 304 # endif /* JOBDEBUG */
 305                 (void) signal(SIGINT,SIG_IGN); /* may not be necessary */
 306                 (void) signal(SIGQUIT,SIG_IGN);
 307             }
 308 #endif /* COHERENT */
 309
 310             texec(*av, av);
 311 }
 312         else {
 313             dp = Strspl(*pv, sav);
 314 #ifdef VFORK
 315             Vdp = dp;
 316 #endif /* VFORK */
 317
 318 #ifdef COHERENT
 319             if ((t->t_dflg & F_AMPERSAND)) {
 320 # ifdef JOBDEBUG
 321                 xprintf("set SIGINT to SIG_IGN\n");
 322 # endif /* JOBDEBUG */
 323                 /*
 324                  * this is necessary on Coherent or all background
 325                  * jobs are killed by CTRL-C
 326                  * (there must be a better fix for this)
 327                  */
 328                 (void) signal(SIGINT,SIG_IGN);
 329             }
 330             if (gointr && eq(gointr,STRminus)) {
 331 # ifdef JOBDEBUG
 332                 xprintf("set SIGINT to SIG_IGN\n");
 333                 xprintf("set SIGQUIT to SIG_IGN\n");
 334 # endif /* JOBDEBUG */
 335                 (void) signal(SIGINT,SIG_IGN); /* may not be necessary */
 336                 (void) signal(SIGQUIT,SIG_IGN);
 337             }
 338 #endif /* COHERENT */
 339
 340             texec(dp, av);
 341 #ifdef VFORK
 342             Vdp = 0;
 343 #endif /* VFORK */
 344             xfree((ptr_t) dp);
 345         }
 346 #ifdef VFORK
 347         misses++;
 348 #endif /* VFORK */
 349 cont:
 350         pv++;
 351         i++;
 352     } while (*pv);
 353 #ifdef VFORK
 354     hits--;
 355     Vsav = 0;
 356 #endif /* VFORK */
 357     xfree((ptr_t) sav);
 358     pexerr();
 359 }
 360
 361 static void
 362 pexerr()
 363 {
 364     /* Couldn't find the damn thing */
 365     if (expath) {
 366         setname(short2str(expath));
 367 #ifdef VFORK
 368         Vexpath = 0;
 369 #endif /* VFORK */
 370         xfree((ptr_t) expath);
 371         expath = 0;
 372     }
 373     else
 374         setname("");
 375     if (exerr)
 376         stderror(ERR_NAME | ERR_STRING, exerr);
 377     stderror(ERR_NAME | ERR_COMMAND);
 378 }
 379
 380 /*
 381  * Execute command f, arg list t.
 382  * Record error message if not found.
 383  * Also do shell scripts here.
 384  */
 385 static void
 386 texec(sf, st)
 387     Char   *sf;
 388     register Char **st;
 389 {
 390     register char **t;
 391     register char *f;
 392     register struct varent *v;
 393     Char  **vp;
 394     Char   *lastsh[2];
 395     char    pref[2];
 396     int     fd;
 397     Char   *st0, **ost;
 398
 399     /* The order for the conversions is significant */
 400     t = short2blk(st);
 401     f = short2str(sf);
 402 #ifdef VFORK
 403     Vt = t;
 404 #endif /* VFORK */
 405     errno = 0;                  /* don't use a previous error */
 406 #ifdef apollo
 407     /*
 408      * If we try to execute an nfs mounted directory on the apollo, we
 409      * hang forever. So until apollo fixes that..
 410      */
 411     {
 412         struct stat stb;
 413         if (stat(f, &stb) == 0 && S_ISDIR(stb.st_mode))
 414             errno = EISDIR;
 415     }
 416     if (errno == 0)
 417 #endif /* apollo */
 418     {
 419 #ifdef ISC_POSIX_EXEC_BUG
 420         __setostype(0);         /* "0" is "__OS_SYSV" in <sys/user.h> */
 421 #endif /* ISC_POSIX_EXEC_BUG */
 422         (void) execv(f, t);
 423 #ifdef ISC_POSIX_EXEC_BUG
 424         __setostype(1);         /* "1" is "__OS_POSIX" in <sys/user.h> */
 425 #endif /* ISC_POSIX_EXEC_BUG */
 426     }
 427 #ifdef VFORK
 428     Vt = 0;
 429 #endif /* VFORK */
 430     blkfree((Char **) t);
 431     switch (errno) {
 432
 433     case ENOEXEC:
 434 #ifdef WINNT_NATIVE
 435                 nt_feed_to_cmd(f,t);
 436 #endif /* WINNT_NATIVE */
 437         /*
 438          * From: casper@fwi.uva.nl (Casper H.S. Dik) If we could not execute
 439          * it, don't feed it to the shell if it looks like a binary!
 440          */
 441         if ((fd = open(f, O_RDONLY)) != -1) {
 442             int nread;
 443             if ((nread = read(fd, (char *) pref, 2)) == 2) {
 444                 if (!Isprint(pref[0]) && (pref[0] != '\n' && pref[0] != '\t')) {
 445                     (void) close(fd);
 446                     /*
 447                      * We *know* what ENOEXEC means.
 448                      */
 449                     stderror(ERR_ARCH, f, strerror(errno));
 450                 }
 451             }
 452             else if (nread < 0 && errno != EINTR) {
 453 #ifdef convex
 454                 /* need to print error incase the file is migrated */
 455                 stderror(ERR_SYSTEM, f, strerror(errno));
 456 #endif
 457             }
 458 #ifdef _PATH_BSHELL
 459             else {
 460                 pref[0] = '#';
 461                 pref[1] = '\0';
 462             }
 463 #endif
 464         }
 465 #ifdef HASHBANG
 466         if (fd == -1 ||
 467             pref[0] != '#' || pref[1] != '!' || hashbang(fd, &vp) == -1) {
 468 #endif /* HASHBANG */
 469         /*
 470          * If there is an alias for shell, then put the words of the alias in
 471          * front of the argument list replacing the command name. Note no
 472          * interpretation of the words at this point.
 473          */
 474             v = adrof1(STRshell, &aliases);
 475             if (v == NULL || v->vec == NULL) {
 476                 vp = lastsh;
 477                 vp[0] = adrof(STRshell) ? varval(STRshell) : STR_SHELLPATH;
 478                 vp[1] = NULL;
 479 #ifdef _PATH_BSHELL
 480                 if (fd != -1
 481 # ifndef ISC    /* Compatible with ISC's /bin/csh */
 482                     && pref[0] != '#'
 483 # endif /* ISC */
 484                     )
 485                     vp[0] = STR_BSHELL;
 486 #endif
 487                 vp = saveblk(vp);
 488             }
 489             else
 490                 vp = saveblk(v->vec);
 491 #ifdef HASHBANG
 492         }
 493 #endif /* HASHBANG */
 494         if (fd != -1)
 495             (void) close(fd);
 496
 497         st0 = st[0];
 498         st[0] = sf;
 499         ost = st;
 500         st = blkspl(vp, st);    /* Splice up the new arglst */
 501         ost[0] = st0;
 502         sf = *st;
 503         /* The order for the conversions is significant */
 504         t = short2blk(st);
 505         f = short2str(sf);
 506         xfree((ptr_t) st);
 507         blkfree((Char **) vp);
 508 #ifdef VFORK
 509         Vt = t;
 510 #endif /* VFORK */
 511 #ifdef ISC_POSIX_EXEC_BUG
 512         __setostype(0);         /* "0" is "__OS_SYSV" in <sys/user.h> */
 513 #endif /* ISC_POSIX_EXEC_BUG */
 514         (void) execv(f, t);
 515 #ifdef ISC_POSIX_EXEC_BUG
 516         __setostype(1);         /* "1" is "__OS_POSIX" in <sys/user.h> */
 517 #endif /* ISC_POSIX_EXEC_BUG */
 518 #ifdef VFORK
 519         Vt = 0;
 520 #endif /* VFORK */
 521         blkfree((Char **) t);
 522         /* The sky is falling, the sky is falling! */
 523         stderror(ERR_SYSTEM, f, strerror(errno));
 524         break;
 525
 526     case ENOMEM:
 527         stderror(ERR_SYSTEM, f, strerror(errno));
 528         break;
 529
 530 #ifdef _IBMR2
 531     case 0:                     /* execv fails and returns 0! */
 532 #endif /* _IBMR2 */
 533     case ENOENT:
 534         break;
 535
 536     default:
 537         if (exerr == 0) {
 538             exerr = strerror(errno);
 539             if (expath)
 540                 xfree((ptr_t) expath);
 541             expath = Strsave(sf);
 542 #ifdef VFORK
 543             Vexpath = expath;
 544 #endif /* VFORK */
 545         }
 546         break;
 547     }
 548 }
 549
 550 /*ARGSUSED*/
 551 void
 552 execash(t, kp)
 553     Char  **t;
 554     register struct command *kp;
 555 {
 556     int     saveIN, saveOUT, saveDIAG, saveSTD;
 557     int     oSHIN;
 558     int     oSHOUT;
 559     int     oSHDIAG;
 560     int     oOLDSTD;
 561     jmp_buf_t osetexit;
 562     int     my_reenter;
 563     int     odidfds;
 564 #ifndef CLOSE_ON_EXEC
 565     int     odidcch;
 566 #endif /* CLOSE_ON_EXEC */
 567     signalfun_t osigint, osigquit, osigterm;
 568
 569     USE(t);
 570     if (chkstop == 0 && setintr)
 571         panystop(0);
 572     /*
 573      * Hmm, we don't really want to do that now because we might
 574      * fail, but what is the choice
 575      */
 576     rechist(NULL, adrof(STRsavehist) != NULL);
 577
 578
 579     osigint  = signal(SIGINT, parintr);
 580     osigquit = signal(SIGQUIT, parintr);
 581     osigterm = signal(SIGTERM, parterm);
 582
 583     odidfds = didfds;
 584 #ifndef CLOSE_ON_EXEC
 585     odidcch = didcch;
 586 #endif /* CLOSE_ON_EXEC */
 587     oSHIN = SHIN;
 588     oSHOUT = SHOUT;
 589     oSHDIAG = SHDIAG;
 590     oOLDSTD = OLDSTD;
 591
 592     saveIN = dcopy(SHIN, -1);
 593     saveOUT = dcopy(SHOUT, -1);
 594     saveDIAG = dcopy(SHDIAG, -1);
 595     saveSTD = dcopy(OLDSTD, -1);
 596
 597     lshift(kp->t_dcom, 1);
 598
 599     getexit(osetexit);
 600
 601     /* PWP: setjmp/longjmp bugfix for optimizing compilers */
 602 #ifdef cray
 603     my_reenter = 1;             /* assume non-zero return val */
 604     if (setexit() == 0) {
 605         my_reenter = 0;         /* Oh well, we were wrong */
 606 #else /* !cray */
 607     if ((my_reenter = setexit()) == 0) {
 608 #endif /* cray */
 609         SHIN = dcopy(0, -1);
 610         SHOUT = dcopy(1, -1);
 611         SHDIAG = dcopy(2, -1);
 612 #ifndef CLOSE_ON_EXEC
 613         didcch = 0;
 614 #endif /* CLOSE_ON_EXEC */
 615         didfds = 0;
 616         /*
 617          * Decrement the shell level
 618          */
 619         shlvl(-1);
 620 #ifdef WINNT_NATIVE
 621         __nt_really_exec=1;
 622 #endif /* WINNT_NATIVE */
 623         doexec(kp, 1);
 624     }
 625
 626     (void) sigset(SIGINT, osigint);
 627     (void) sigset(SIGQUIT, osigquit);
 628     (void) sigset(SIGTERM, osigterm);
 629
 630     doneinp = 0;
 631 #ifndef CLOSE_ON_EXEC
 632     didcch = odidcch;
 633 #endif /* CLOSE_ON_EXEC */
 634     didfds = odidfds;
 635     (void) close(SHIN);
 636     (void) close(SHOUT);
 637     (void) close(SHDIAG);
 638     (void) close(OLDSTD);
 639     SHIN = dmove(saveIN, oSHIN);
 640     SHOUT = dmove(saveOUT, oSHOUT);
 641     SHDIAG = dmove(saveDIAG, oSHDIAG);
 642     OLDSTD = dmove(saveSTD, oOLDSTD);
 643
 644     resexit(osetexit);
 645     if (my_reenter)
 646         stderror(ERR_SILENT);
 647 }
 648
 649 void
 650 xechoit(t)
 651     Char  **t;
 652 {
 653     if (adrof(STRecho)) {
 654         int odidfds = didfds;
 655         flush();
 656         haderr = 1;
 657         didfds = 0;
 658         blkpr(t), xputchar('\n');
 659         flush();
 660         didfds = odidfds;
 661         haderr = 0;
 662     }
 663 }
 664
 665 /*ARGSUSED*/
 666 void
 667 dohash(vv, c)
 668     Char **vv;
 669     struct command *c;
 670 {
 671 #ifdef COMMENT
 672     struct stat stb;
 673 #endif
 674     DIR    *dirp;
 675     register struct dirent *dp;
 676     int     i = 0;
 677     struct varent *v = adrof(STRpath);
 678     Char  **pv;
 679     int hashval;
 680 #ifdef WINNT_NATIVE
 681     int is_windir; /* check if it is the windows directory */
 682     USE(hashval);
 683 #endif /* WINNT_NATIVE */
 684
 685     USE(c);
 686 #ifdef FASTHASH
 687     if (vv && vv[1]) {
 688         uhashlength = atoi(short2str(vv[1]));
 689         if (vv[2]) {
 690             uhashwidth = atoi(short2str(vv[2]));
 691             if ((uhashwidth != sizeof(unsigned char)) &&
 692                 (uhashwidth != sizeof(unsigned short)) &&
 693                 (uhashwidth != sizeof(unsigned long)))
 694                 uhashwidth = 0;
 695             if (vv[3])
 696                 hashdebug = atoi(short2str(vv[3]));
 697         }
 698     }
 699
 700     if (uhashwidth)
 701         hashwidth = uhashwidth;
 702     else {
 703         hashwidth = 0;
 704         if (v == NULL)
 705             return;
 706         for (pv = v->vec; pv && *pv; pv++, hashwidth++)
 707             continue;
 708         if (hashwidth <= widthof(unsigned char))
 709             hashwidth = sizeof(unsigned char);
 710         else if (hashwidth <= widthof(unsigned short))
 711             hashwidth = sizeof(unsigned short);
 712         else if (hashwidth <= widthof(unsigned int))
 713             hashwidth = sizeof(unsigned int);
 714         else
 715             hashwidth = sizeof(unsigned long);
 716     }
 717
 718     if (uhashlength)
 719         hashlength = uhashlength;
 720     else
 721         hashlength = hashwidth * (8*64);/* "average" files per dir in path */
 722
 723     if (xhash)
 724         xfree((ptr_t) xhash);
 725     xhash = (unsigned long *) xcalloc((size_t) (hashlength * hashwidth),
 726                                       (size_t) 1);
 727 #endif /* FASTHASH */
 728
 729     (void) getusername(NULL);   /* flush the tilde cashe */
 730     tw_cmd_free();
 731     havhash = 1;
 732     if (v == NULL)
 733         return;
 734     for (pv = v->vec; pv && *pv; pv++, i++) {
 735         if (!ABSOLUTEP(pv[0]))
 736             continue;
 737         dirp = opendir(short2str(*pv));
 738         if (dirp == NULL)
 739             continue;
 740 #ifdef COMMENT                  /* this isn't needed.  opendir won't open
 741                                  * non-dirs */
 742         if (fstat(dirp->dd_fd, &stb) < 0 || !S_ISDIR(stb.st_mode)) {
 743             (void) closedir(dirp);
 744             continue;
 745         }
 746 #endif
 747 #ifdef WINNT_NATIVE
 748         is_windir = nt_check_if_windir(short2str(*pv));
 749 #endif /* WINNT_NATIVE */
 750         while ((dp = readdir(dirp)) != NULL) {
 751             if (dp->d_ino == 0)
 752                 continue;
 753             if (dp->d_name[0] == '.' &&
 754                 (dp->d_name[1] == '\0' ||
 755                  (dp->d_name[1] == '.' && dp->d_name[2] == '\0')))
 756                 continue;
 757 #ifdef WINNT_NATIVE
 758             nt_check_name_and_hash(is_windir, dp->d_name, i);
 759 #else /* !WINNT_NATIVE*/
 760 #if defined(_UWIN) || defined(__CYGWIN__)
 761             /* Turn foo.{exe,com,bat} into foo since UWIN's readdir returns
 762              * the file with the .exe, .com, .bat extension
 763              */
 764             {
 765                 size_t  ext = strlen(dp->d_name) - 4;
 766                 if ((ext > 0) && (strcmp(&dp->d_name[ext], ".exe") == 0 ||
 767                                   strcmp(&dp->d_name[ext], ".bat") == 0 ||
 768                                   strcmp(&dp->d_name[ext], ".com") == 0))
 769                     dp->d_name[ext] = '\0';
 770             }
 771 #endif /* _UWIN || __CYGWIN__ */
 772 # ifdef FASTHASH
 773             hashval = hashname(str2short(dp->d_name));
 774             bis(hashval, i);
 775             if (hashdebug & 1)
 776                 xprintf(CGETS(13, 1, "hash=%-4d dir=%-2d prog=%s\n"),
 777                         hashname(str2short(dp->d_name)), i, dp->d_name);
 778 # else /* OLD HASH */
 779             hashval = hash(hashname(str2short(dp->d_name)), i);
 780             bis(xhash, hashval);
 781 # endif /* FASTHASH */
 782             /* tw_add_comm_name (dp->d_name); */
 783 #endif /* WINNT_NATIVE */
 784         }
 785         (void) closedir(dirp);
 786     }
 787 }
 788
 789 /*ARGSUSED*/
 790 void
 791 dounhash(v, c)
 792     Char **v;
 793     struct command *c;
 794 {
 795     USE(c);
 796     USE(v);
 797     havhash = 0;
 798 #ifdef FASTHASH
 799     if (xhash) {
 800        xfree((ptr_t) xhash);
 801        xhash = NULL;
 802     }
 803 #endif /* FASTHASH */
 804 }
 805
 806 /*ARGSUSED*/
 807 void
 808 hashstat(v, c)
 809     Char **v;
 810     struct command *c;
 811 {
 812     USE(c);
 813     USE(v);
 814 #ifdef FASTHASH
 815    if (havhash && hashlength && hashwidth)
 816       xprintf(CGETS(13, 2, "%d hash buckets of %d bits each\n"),
 817               hashlength, hashwidth*8);
 818    if (hashdebug)
 819       xprintf(CGETS(13, 3, "debug mask = 0x%08x\n"), hashdebug);
 820 #endif /* FASTHASH */
 821 #ifdef VFORK
 822    if (hits + misses)
 823       xprintf(CGETS(13, 4, "%d hits, %d misses, %d%%\n"),
 824               hits, misses, 100 * hits / (hits + misses));
 825 #endif
 826 }
 827
 828
 829 /*
 830  * Hash a command name.
 831  */
 832 int
 833 hashname(cp)
 834     register Char *cp;
 835 {
 836     register unsigned long h;
 837
 838     for (h = 0; *cp; cp++)
 839         h = hash(h, *cp);
 840     return ((int) h);
 841 }
 842
 843 static int
 844 iscommand(name)
 845     Char   *name;
 846 {
 847     register Char **pv;
 848     register Char *sav;
 849     register struct varent *v;
 850     register bool slash = any(short2str(name), '/');
 851     register int hashval, i;
 852
 853     v = adrof(STRpath);
 854     if (v == NULL || v->vec == NULL || v->vec[0] == NULL || slash)
 855         pv = justabs;
 856     else
 857         pv = v->vec;
 858     sav = Strspl(STRslash, name);       /* / command name for postpending */
 859     hashval = havhash ? hashname(name) : 0;
 860     i = 0;
 861     do {
 862         if (!slash && ABSOLUTEP(pv[0]) && havhash) {
 863 #ifdef FASTHASH
 864             if (!bit(hashval, i))
 865                 goto cont;
 866 #else /* OLDHASH */
 867             int hashval1 = hash(hashval, i);
 868             if (!bit(xhash, hashval1))
 869                 goto cont;
 870 #endif /* FASTHASH */
 871         }
 872         if (pv[0][0] == 0 || eq(pv[0], STRdot)) {       /* don't make ./xxx */
 873             if (executable(NULL, name, 0)) {
 874                 xfree((ptr_t) sav);
 875                 return i + 1;
 876             }
 877         }
 878         else {
 879             if (executable(*pv, sav, 0)) {
 880                 xfree((ptr_t) sav);
 881                 return i + 1;
 882             }
 883         }
 884 cont:
 885         pv++;
 886         i++;
 887     } while (*pv);
 888     xfree((ptr_t) sav);
 889     return 0;
 890 }
 891
 892 /* Also by:
 893  *  Andreas Luik <luik@isaak.isa.de>
 894  *  I S A  GmbH - Informationssysteme fuer computerintegrierte Automatisierung
 895  *  Azenberstr. 35
 896  *  D-7000 Stuttgart 1
 897  *  West-Germany
 898  * is the executable() routine below and changes to iscommand().
 899  * Thanks again!!
 900  */
 901
 902 #ifndef WINNT_NATIVE
 903 /*
 904  * executable() examines the pathname obtained by concatenating dir and name
 905  * (dir may be NULL), and returns 1 either if it is executable by us, or
 906  * if dir_ok is set and the pathname refers to a directory.
 907  * This is a bit kludgy, but in the name of optimization...
 908  */
 909 int
 910 executable(dir, name, dir_ok)
 911     Char   *dir, *name;
 912     bool    dir_ok;
 913 {
 914     struct stat stbuf;
 915     Char    path[MAXPATHLEN + 1];
 916     char   *strname;
 917     (void) memset(path, 0, sizeof(path));
 918
 919     if (dir && *dir) {
 920         copyn(path, dir, MAXPATHLEN);
 921         catn(path, name, MAXPATHLEN);
 922         strname = short2str(path);
 923     }
 924     else
 925         strname = short2str(name);
 926
 927     return (stat(strname, &stbuf) != -1 &&
 928             ((dir_ok && S_ISDIR(stbuf.st_mode)) ||
 929              (S_ISREG(stbuf.st_mode) &&
 930     /* save time by not calling access() in the hopeless case */
 931               (stbuf.st_mode & (S_IXOTH | S_IXGRP | S_IXUSR)) &&
 932               access(strname, X_OK) == 0
 933         )));
 934 }
 935 #endif /*!WINNT_NATIVE*/
 936
 937 int
 938 tellmewhat(lexp, str)
 939     struct wordent *lexp;
 940     Char *str;
 941 {
 942     register int i;
 943     register struct biltins *bptr;
 944     register struct wordent *sp = lexp->next;
 945     bool    aliased = 0, found;
 946     Char   *s0, *s1, *s2, *cmd;
 947     Char    qc;
 948
 949     if (adrof1(sp->word, &aliases)) {
 950         alias(lexp);
 951         sp = lexp->next;
 952         aliased = 1;
 953     }
 954
 955     s0 = sp->word;              /* to get the memory freeing right... */
 956
 957     /* handle quoted alias hack */
 958     if ((*(sp->word) & (QUOTE | TRIM)) == QUOTE)
 959         (sp->word)++;
 960
 961     /* do quoting, if it hasn't been done */
 962     s1 = s2 = sp->word;
 963     while (*s2)
 964         switch (*s2) {
 965         case '\'':
 966         case '"':
 967             qc = *s2++;
 968             while (*s2 && *s2 != qc)
 969                 *s1++ = *s2++ | QUOTE;
 970             if (*s2)
 971                 s2++;
 972             break;
 973         case '\\':
 974             if (*++s2)
 975                 *s1++ = *s2++ | QUOTE;
 976             break;
 977         default:
 978             *s1++ = *s2++;
 979         }
 980     *s1 = '\0';
 981
 982     for (bptr = bfunc; bptr < &bfunc[nbfunc]; bptr++) {
 983         if (eq(sp->word, str2short(bptr->bname))) {
 984             if (str == NULL) {
 985                 if (aliased)
 986                     prlex(lexp);
 987                 xprintf(CGETS(13, 5, "%S: shell built-in command.\n"),
 988                               sp->word);
 989                 flush();
 990             }
 991             else
 992                 (void) Strcpy(str, sp->word);
 993             sp->word = s0;      /* we save and then restore this */
 994             return TRUE;
 995         }
 996     }
 997 #ifdef WINNT_NATIVE
 998     for (bptr = nt_bfunc; bptr < &nt_bfunc[nt_nbfunc]; bptr++) {
 999         if (eq(sp->word, str2short(bptr->bname))) {
1000             if (str == NULL) {
1001                 if (aliased)
1002                     prlex(lexp);
1003                 xprintf(CGETS(13, 5, "%S: shell built-in command.\n"),
1004                               sp->word);
1005                 flush();
1006             }
1007             else
1008                 (void) Strcpy(str, sp->word);
1009             sp->word = s0;      /* we save and then restore this */
1010             return TRUE;
1011         }
1012     }
1013 #endif /* WINNT_NATIVE*/
1014
1015     sp->word = cmd = globone(sp->word, G_IGNORE);
1016
1017     if ((i = iscommand(sp->word)) != 0) {
1018         register Char **pv;
1019         register struct varent *v;
1020         bool    slash = any(short2str(sp->word), '/');
1021
1022         v = adrof(STRpath);
1023         if (v == NULL || v->vec == NULL || v->vec[0] == NULL || slash)
1024             pv = justabs;
1025         else
1026             pv = v->vec;
1027
1028         while (--i)
1029             pv++;
1030         if (pv[0][0] == 0 || eq(pv[0], STRdot)) {
1031             if (!slash) {
1032                 sp->word = Strspl(STRdotsl, sp->word);
1033                 prlex(lexp);
1034                 xfree((ptr_t) sp->word);
1035             }
1036             else
1037                 prlex(lexp);
1038         }
1039         else {
1040             s1 = Strspl(*pv, STRslash);
1041             sp->word = Strspl(s1, sp->word);
1042             xfree((ptr_t) s1);
1043             if (str == NULL)
1044                 prlex(lexp);
1045             else
1046                 (void) Strcpy(str, sp->word);
1047             xfree((ptr_t) sp->word);
1048         }
1049         found = 1;
1050     }
1051     else {
1052         if (str == NULL) {
1053             if (aliased)
1054                 prlex(lexp);
1055             xprintf(CGETS(13, 6, "%S: Command not found.\n"), sp->word);
1056             flush();
1057         }
1058         else
1059             (void) Strcpy(str, sp->word);
1060         found = 0;
1061     }
1062     sp->word = s0;              /* we save and then restore this */
1063     xfree((ptr_t) cmd);
1064     return found;
1065 }
1066
1067 /*
1068  * Builtin to look at and list all places a command may be defined:
1069  * aliases, shell builtins, and the path.
1070  *
1071  * Marc Horowitz <marc@mit.edu>
1072  * MIT Student Information Processing Board
1073  */
1074
1075 /*ARGSUSED*/
1076 void
1077 dowhere(v, c)
1078     register Char **v;
1079     struct command *c;
1080 {
1081     int found = 1;
1082     USE(c);
1083     for (v++; *v; v++)
1084         found &= find_cmd(*v, 1);
1085     /* Make status nonzero if any command is not found. */
1086     if (!found)
1087       set(STRstatus, Strsave(STR1), VAR_READWRITE);
1088 }
1089
1090 int
1091 find_cmd(cmd, prt)
1092     Char *cmd;
1093     int prt;
1094 {
1095     struct varent *var;
1096     struct biltins *bptr;
1097     Char **pv;
1098     Char *sv;
1099     int hashval, i, ex, rval = 0;
1100
1101     if (prt && any(short2str(cmd), '/')) {
1102         xprintf(CGETS(13, 7, "where: / in command makes no sense\n"));
1103         return rval;
1104     }
1105
1106     /* first, look for an alias */
1107
1108     if (prt && adrof1(cmd, &aliases)) {
1109         if ((var = adrof1(cmd, &aliases)) != NULL) {
1110             xprintf(CGETS(13, 8, "%S is aliased to "), cmd);
1111             if (var->vec != NULL)
1112                 blkpr(var->vec);
1113             xputchar('\n');
1114             rval = 1;
1115         }
1116     }
1117
1118     /* next, look for a shell builtin */
1119
1120     for (bptr = bfunc; bptr < &bfunc[nbfunc]; bptr++) {
1121         if (eq(cmd, str2short(bptr->bname))) {
1122             rval = 1;
1123             if (prt)
1124                 xprintf(CGETS(13, 9, "%S is a shell built-in\n"), cmd);
1125             else
1126                 return rval;
1127         }
1128     }
1129 #ifdef WINNT_NATIVE
1130     for (bptr = nt_bfunc; bptr < &nt_bfunc[nt_nbfunc]; bptr++) {
1131         if (eq(cmd, str2short(bptr->bname))) {
1132             rval = 1;
1133             if (prt)
1134                 xprintf(CGETS(13, 9, "%S is a shell built-in\n"), cmd);
1135             else
1136                 return rval;
1137         }
1138     }
1139 #endif /* WINNT_NATIVE*/
1140
1141     /* last, look through the path for the command */
1142
1143     if ((var = adrof(STRpath)) == NULL)
1144         return rval;
1145
1146     hashval = havhash ? hashname(cmd) : 0;
1147
1148     sv = Strspl(STRslash, cmd);
1149
1150     for (pv = var->vec, i = 0; pv && *pv; pv++, i++) {
1151         if (havhash && !eq(*pv, STRdot)) {
1152 #ifdef FASTHASH
1153             if (!bit(hashval, i))
1154                 continue;
1155 #else /* OLDHASH */
1156             int hashval1 = hash(hashval, i);
1157             if (!bit(xhash, hashval1))
1158                 continue;
1159 #endif /* FASTHASH */
1160         }
1161         ex = executable(*pv, sv, 0);
1162 #ifdef FASTHASH
1163         if (!ex && (hashdebug & 2)) {
1164             xprintf(CGETS(13, 10, "hash miss: "));
1165             ex = 1;     /* Force printing */
1166         }
1167 #endif /* FASTHASH */
1168         if (ex) {
1169             rval = 1;
1170             if (prt) {
1171                 xprintf("%S/", *pv);
1172                 xprintf("%S\n", cmd);
1173             }
1174             else
1175                 return rval;
1176         }
1177     }
1178     xfree((ptr_t) sv);
1179     return rval;
1180 }
1181 #ifdef WINNT_NATIVE
1182 int hashval_extern(cp)
1183         Char *cp;
1184 {
1185         return havhash?hashname(cp):0;
1186 }
1187 int bit_extern(val,i)
1188         int val;
1189         int i;
1190 {
1191         return bit(val,i);
1192 }
1193 void bis_extern(val,i)
1194         int val;
1195         int i;
1196 {
1197         bis(val,i);
1198 }
1199 #endif /* WINNT_NATIVE */
1200