bin/csh/exec.c

   1 /* $NetBSD: exec.c,v 1.27 2007/12/15 19:44:37 perry Exp $ */
   2
   3 /*-
   4  * Copyright (c) 1980, 1991, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #include <sys/cdefs.h>
  33 #ifndef lint
  34 #if 0
  35 static char sccsid[] = "@(#)exec.c      8.3 (Berkeley) 5/23/95";
  36 #else
  37 __RCSID("$NetBSD: exec.c,v 1.27 2007/12/15 19:44:37 perry Exp $");
  38 #endif
  39 #endif /* not lint */
  40
  41 #include <sys/param.h>
  42 #include <sys/stat.h>
  43 #include <sys/types.h>
  44
  45 #include <dirent.h>
  46 #include <errno.h>
  47 #include <fcntl.h>
  48 #include <stdarg.h>
  49 #include <stdlib.h>
  50 #include <string.h>
  51 #include <unistd.h>
  52
  53 #include "csh.h"
  54 #include "extern.h"
  55
  56 /*
  57  * System level search and execute of a command.  We look in each directory
  58  * for the specified command name.  If the name contains a '/' then we
  59  * execute only the full path name.  If there is no search path then we
  60  * execute only full path names.
  61  */
  62 extern char **environ;
  63
  64 /*
  65  * As we search for the command we note the first non-trivial error
  66  * message for presentation to the user.  This allows us often
  67  * to show that a file has the wrong mode/no access when the file
  68  * is not in the last component of the search path, so we must
  69  * go on after first detecting the error.
  70  */
  71 static const char *exerr;       /* Execution error message */
  72 static Char *expath;            /* Path for exerr */
  73
  74 /*
  75  * Xhash is an array of HSHSIZ bits (HSHSIZ / 8 chars), which are used
  76  * to hash execs.  If it is allocated (havhash true), then to tell
  77  * whether ``name'' is (possibly) present in the i'th component
  78  * of the variable path, you look at the bit in xhash indexed by
  79  * hash(hashname("name"), i).  This is setup automatically
  80  * after .login is executed, and recomputed whenever ``path'' is
  81  * changed.
  82  * The two part hash function is designed to let texec() call the
  83  * more expensive hashname() only once and the simple hash() several
  84  * times (once for each path component checked).
  85  * Byte size is assumed to be 8.
  86  */
  87 #define HSHSIZ 8192     /* 1k bytes */
  88 #define HSHMASK (HSHSIZ - 1)
  89 #define HSHMUL 243
  90 static char xhash[HSHSIZ / 8];
  91
  92 #define hash(a, b) (((a) * HSHMUL + (b)) & HSHMASK)
  93 #define bit(h, b) ((h)[(b) >> 3] & 1 << ((b) & 7))      /* bit test */
  94 #define bis(h, b) ((h)[(b) >> 3] |= 1 << ((b) & 7))     /* bit set */
  95 static int hits, misses;
  96
  97 /* Dummy search path for just absolute search when no path */
  98 static Char *justabs[] = {STRNULL, 0};
  99
 100 static void pexerr(void) __dead;
 101 static void texec(Char *, Char **);
 102 static int hashname(Char *);
 103 static int tellmewhat(struct wordent *, Char *);
 104 static int executable(Char *, Char *, int);
 105 static int iscommand(Char *);
 106
 107 void
 108 /*ARGSUSED*/
 109 doexec(Char **v, struct command *t)
 110 {
 111     struct varent *pathv;
 112     Char *blk[2], **av, *dp, **pv, *sav;
 113     int i, hashval, hashval1;
 114     sigset_t nsigset;
 115     int slash;
 116
 117     hashval = 0;
 118     /*
 119      * Glob the command name. We will search $path even if this does something,
 120      * as in sh but not in csh.  One special case: if there is no PATH, then we
 121      * execute only commands which start with '/'.
 122      */
 123     blk[0] = t->t_dcom[0];
 124     blk[1] = 0;
 125     gflag = 0, tglob(blk);
 126     if (gflag) {
 127         pv = globall(blk);
 128         if (pv == 0) {
 129             setname(vis_str(blk[0]));
 130             stderror(ERR_NAME | ERR_NOMATCH);
 131         }
 132         gargv = 0;
 133     }
 134     else
 135         pv = saveblk(blk);
 136
 137     trim(pv);
 138
 139     exerr = 0;
 140     expath = Strsave(pv[0]);
 141     Vexpath = expath;
 142
 143     pathv = adrof(STRpath);
 144     if (pathv == 0 && expath[0] != '/') {
 145         blkfree(pv);
 146         pexerr();
 147     }
 148     slash = any(short2str(expath), '/');
 149
 150     /*
 151      * Glob the argument list, if necessary. Otherwise trim off the quote bits.
 152      */
 153     gflag = 0;
 154     av = &t->t_dcom[1];
 155     tglob(av);
 156     if (gflag) {
 157         av = globall(av);
 158         if (av == 0) {
 159             blkfree(pv);
 160             setname(vis_str(expath));
 161             stderror(ERR_NAME | ERR_NOMATCH);
 162         }
 163         gargv = 0;
 164     }
 165     else
 166         av = saveblk(av);
 167
 168     blkfree(t->t_dcom);
 169     t->t_dcom = blkspl(pv, av);
 170     xfree((ptr_t) pv);
 171     xfree((ptr_t) av);
 172     av = t->t_dcom;
 173     trim(av);
 174
 175     if (*av == NULL || **av == '\0')
 176         pexerr();
 177
 178     xechoit(av);                /* Echo command if -x */
 179     /*
 180      * Since all internal file descriptors are set to close on exec, we don't
 181      * need to close them explicitly here.  Just reorient ourselves for error
 182      * messages.
 183      */
 184     SHIN = 0;
 185     SHOUT = 1;
 186     SHERR = 2;
 187     OLDSTD = 0;
 188     /*
 189      * We must do this AFTER any possible forking (like `foo` in glob) so that
 190      * this shell can still do subprocesses.
 191      */
 192     sigemptyset(&nsigset);
 193     (void)sigprocmask(SIG_SETMASK, &nsigset, NULL);
 194     /*
 195      * If no path, no words in path, or a / in the filename then restrict the
 196      * command search.
 197      */
 198     if (pathv == 0 || pathv->vec[0] == 0 || slash)
 199         pv = justabs;
 200     else
 201         pv = pathv->vec;
 202     sav = Strspl(STRslash, *av);        /* / command name for postpending */
 203     Vsav = sav;
 204     if (havhash)
 205         hashval = hashname(*av);
 206     i = 0;
 207     hits++;
 208     do {
 209         /*
 210          * Try to save time by looking at the hash table for where this command
 211          * could be.  If we are doing delayed hashing, then we put the names in
 212          * one at a time, as the user enters them.  This is kinda like Korn
 213          * Shell's "tracked aliases".
 214          */
 215         if (!slash && pv[0][0] == '/' && havhash) {
 216             hashval1 = hash(hashval, i);
 217             if (!bit(xhash, hashval1))
 218                 goto cont;
 219         }
 220         if (pv[0][0] == 0 || eq(pv[0], STRdot)) /* don't make ./xxx */
 221             texec(*av, av);
 222         else {
 223             dp = Strspl(*pv, sav);
 224             Vdp = dp;
 225             texec(dp, av);
 226             Vdp = 0;
 227             xfree((ptr_t)dp);
 228         }
 229         misses++;
 230 cont:
 231         pv++;
 232         i++;
 233     } while (*pv);
 234     hits--;
 235     Vsav = 0;
 236     xfree((ptr_t)sav);
 237     pexerr();
 238     /* NOTREACHED */
 239 }
 240
 241 static void
 242 pexerr(void)
 243 {
 244     /* Couldn't find the damn thing */
 245     if (expath) {
 246         setname(vis_str(expath));
 247         Vexpath = 0;
 248         xfree((ptr_t)expath);
 249         expath = 0;
 250     }
 251     else
 252         setname("");
 253     if (exerr)
 254         stderror(ERR_NAME | ERR_STRING, exerr);
 255     else
 256         stderror(ERR_NAME | ERR_COMMAND);
 257     /* NOTREACHED */
 258 }
 259
 260 /*
 261  * Execute command f, arg list t.
 262  * Record error message if not found.
 263  * Also do shell scripts here.
 264  */
 265 static void
 266 texec(Char *sf, Char **st)
 267 {
 268     struct varent *v;
 269     Char *lastsh[2], **vp, *st0, **ost;
 270     char *f, **t;
 271     int fd;
 272     unsigned char c = '\0';
 273
 274     /* The order for the conversions is significant */
 275     t = short2blk(st);
 276     f = short2str(sf);
 277     Vt = t;
 278     errno = 0;                  /* don't use a previous error */
 279     (void)execve(f, t, environ);
 280     Vt = 0;
 281     blkfree((Char **)t);
 282     switch (errno) {
 283
 284     case ENOEXEC:
 285         /*
 286          * From: casper@fwi.uva.nl (Casper H.S. Dik) If we could not execute
 287          * it, don't feed it to the shell if it looks like a binary!
 288          */
 289         if ((fd = open(f, O_RDONLY)) != -1) {
 290             if (read(fd, (char *)&c, 1) == 1) {
 291                 if (!Isprint(c) && (c != '\n' && c != '\t')) {
 292                     (void)close(fd);
 293                     /*
 294                      * We *know* what ENOEXEC means.
 295                      */
 296                     stderror(ERR_ARCH, f, strerror(errno));
 297                 }
 298             }
 299 #ifdef _PATH_BSHELL
 300             else
 301                 c = '#';
 302 #endif
 303             (void)close(fd);
 304         }
 305         /*
 306          * If there is an alias for shell, then put the words of the alias in
 307          * front of the argument list replacing the command name. Note no
 308          * interpretation of the words at this point.
 309          */
 310         v = adrof1(STRshell, &aliases);
 311         if (v == 0) {
 312             vp = lastsh;
 313             vp[0] = adrof(STRshell) ? value(STRshell) : STR_SHELLPATH;
 314             vp[1] = NULL;
 315 #ifdef _PATH_BSHELL
 316             if (fd != -1 && c != '#')
 317                 vp[0] = STR_BSHELL;
 318 #endif
 319         }
 320         else
 321             vp = v->vec;
 322         st0 = st[0];
 323         st[0] = sf;
 324         ost = st;
 325         st = blkspl(vp, st);    /* Splice up the new arglst */
 326         ost[0] = st0;
 327         sf = *st;
 328         /* The order for the conversions is significant */
 329         t = short2blk(st);
 330         f = short2str(sf);
 331         xfree((ptr_t) st);
 332         Vt = t;
 333         (void)execve(f, t, environ);
 334         Vt = 0;
 335         blkfree((Char **) t);
 336         /* FALLTHROUGH */
 337
 338     case ENOMEM:
 339         stderror(ERR_SYSTEM, f, strerror(errno));
 340         /* NOTREACHED */
 341
 342     case ENOENT:
 343         break;
 344
 345     default:
 346         if (exerr == 0) {
 347             exerr = strerror(errno);
 348             if (expath)
 349                 xfree((ptr_t) expath);
 350             expath = Strsave(sf);
 351             Vexpath = expath;
 352         }
 353     }
 354 }
 355
 356 /*ARGSUSED*/
 357 void
 358 execash(Char **t, struct command *kp)
 359 {
 360     jmp_buf osetexit;
 361     sig_t osigint, osigquit, osigterm;
 362     int my_reenter, odidfds, oOLDSTD, oSHERR, oSHIN, oSHOUT;
 363     int saveDIAG, saveIN, saveOUT, saveSTD;
 364
 365     if (chkstop == 0 && setintr)
 366         panystop(0);
 367     /*
 368      * Hmm, we don't really want to do that now because we might
 369      * fail, but what is the choice
 370      */
 371     rechist();
 372
 373     osigint  = signal(SIGINT, parintr);
 374     osigquit = signal(SIGQUIT, parintr);
 375     osigterm = signal(SIGTERM, parterm);
 376
 377     odidfds = didfds;
 378     oSHIN = SHIN;
 379     oSHOUT = SHOUT;
 380     oSHERR = SHERR;
 381     oOLDSTD = OLDSTD;
 382
 383     saveIN = dcopy(SHIN, -1);
 384     saveOUT = dcopy(SHOUT, -1);
 385     saveDIAG = dcopy(SHERR, -1);
 386     saveSTD = dcopy(OLDSTD, -1);
 387
 388     lshift(kp->t_dcom, 1);
 389
 390     getexit(osetexit);
 391
 392     if ((my_reenter = setexit()) == 0) {
 393         SHIN = dcopy(0, -1);
 394         SHOUT = dcopy(1, -1);
 395         SHERR = dcopy(2, -1);
 396         didfds = 0;
 397         doexec(t, kp);
 398     }
 399
 400     (void)signal(SIGINT, osigint);
 401     (void)signal(SIGQUIT, osigquit);
 402     (void)signal(SIGTERM, osigterm);
 403
 404     doneinp = 0;
 405     didfds = odidfds;
 406     (void)close(SHIN);
 407     (void)close(SHOUT);
 408     (void)close(SHERR);
 409     (void)close(OLDSTD);
 410     SHIN = dmove(saveIN, oSHIN);
 411     SHOUT = dmove(saveOUT, oSHOUT);
 412     SHERR = dmove(saveDIAG, oSHERR);
 413     OLDSTD = dmove(saveSTD, oOLDSTD);
 414
 415     resexit(osetexit);
 416     if (my_reenter)
 417         stderror(ERR_SILENT);
 418 }
 419
 420 void
 421 xechoit(Char **t)
 422 {
 423     if (adrof(STRecho)) {
 424         int odidfds = didfds;
 425         (void)fflush(csherr);
 426         odidfds = didfds;
 427         didfds = 0;
 428         blkpr(csherr, t);
 429         (void)fputc('\n', csherr);
 430         (void)fflush(csherr);
 431         didfds = odidfds;
 432     }
 433 }
 434
 435 void
 436 /*ARGSUSED*/
 437 dohash(Char **v, struct command *t)
 438 {
 439     struct dirent *dp;
 440     struct varent *pathv;
 441     DIR *dirp;
 442     Char **pv;
 443     size_t cnt;
 444     int hashval, i;
 445
 446     i = 0;
 447     havhash = 1;
 448     pathv = adrof(STRpath);
 449
 450     for (cnt = 0; cnt < sizeof xhash; cnt++)
 451         xhash[cnt] = 0;
 452     if (pathv == 0)
 453         return;
 454     for (pv = pathv->vec; *pv; pv++, i++) {
 455         if (pv[0][0] != '/')
 456             continue;
 457         dirp = opendir(short2str(*pv));
 458         if (dirp == NULL)
 459             continue;
 460         while ((dp = readdir(dirp)) != NULL) {
 461             if (dp->d_ino == 0)
 462                 continue;
 463             if (dp->d_name[0] == '.' &&
 464                 (dp->d_name[1] == '\0' ||
 465                  (dp->d_name[1] == '.' && dp->d_name[2] == '\0')))
 466                 continue;
 467             hashval = hash(hashname(str2short(dp->d_name)), i);
 468             bis(xhash, hashval);
 469             /* tw_add_comm_name (dp->d_name); */
 470         }
 471         (void) closedir(dirp);
 472     }
 473 }
 474
 475 void
 476 /*ARGSUSED*/
 477 dounhash(Char **v, struct command *t)
 478 {
 479     havhash = 0;
 480 }
 481
 482 void
 483 /*ARGSUSED*/
 484 hashstat(Char **v, struct command *t)
 485 {
 486     if (hits + misses)
 487         (void)fprintf(cshout, "%d hits, %d misses, %d%%\n",
 488             hits, misses, 100 * hits / (hits + misses));
 489 }
 490
 491 /*
 492  * Hash a command name.
 493  */
 494 static int
 495 hashname(Char *cp)
 496 {
 497     long h = 0;
 498
 499     while (*cp)
 500         h = hash(h, *cp++);
 501     return ((int) h);
 502 }
 503
 504 static int
 505 iscommand(Char *name)
 506 {
 507     struct varent *v;
 508     Char **pv, *sav;
 509     int hashval, hashval1, i;
 510     int slash;
 511
 512     hashval = 0;
 513     slash = any(short2str(name), '/');
 514     v = adrof(STRpath);
 515
 516     if (v == 0 || v->vec[0] == 0 || slash)
 517         pv = justabs;
 518     else
 519         pv = v->vec;
 520     sav = Strspl(STRslash, name);       /* / command name for postpending */
 521     if (havhash)
 522         hashval = hashname(name);
 523     i = 0;
 524     do {
 525         if (!slash && pv[0][0] == '/' && havhash) {
 526             hashval1 = hash(hashval, i);
 527             if (!bit(xhash, hashval1))
 528                 goto cont;
 529         }
 530         if (pv[0][0] == 0 || eq(pv[0], STRdot)) {       /* don't make ./xxx */
 531             if (executable(NULL, name, 0)) {
 532                 xfree((ptr_t) sav);
 533                 return i + 1;
 534             }
 535         }
 536         else {
 537             if (executable(*pv, sav, 0)) {
 538                 xfree((ptr_t) sav);
 539                 return i + 1;
 540             }
 541         }
 542 cont:
 543         pv++;
 544         i++;
 545     } while (*pv);
 546     xfree((ptr_t) sav);
 547     return 0;
 548 }
 549
 550 /* Also by:
 551  *  Andreas Luik <luik@isaak.isa.de>
 552  *  I S A  GmbH - Informationssysteme fuer computerintegrierte Automatisierung
 553  *  Azenberstr. 35
 554  *  D-7000 Stuttgart 1
 555  *  West-Germany
 556  * is the executable() routine below and changes to iscommand().
 557  * Thanks again!!
 558  */
 559
 560 /*
 561  * executable() examines the pathname obtained by concatenating dir and name
 562  * (dir may be NULL), and returns 1 either if it is executable by us, or
 563  * if dir_ok is set and the pathname refers to a directory.
 564  * This is a bit kludgy, but in the name of optimization...
 565  */
 566 static int
 567 executable(Char *dir, Char *name, int dir_ok)
 568 {
 569     struct stat stbuf;
 570     Char path[MAXPATHLEN + 1], *dp, *sp;
 571     char *strname;
 572
 573     if (dir && *dir) {
 574         for (dp = path, sp = dir; *sp; *dp++ = *sp++)
 575             if (dp == &path[MAXPATHLEN + 1]) {
 576                 *--dp = '\0';
 577                 break;
 578             }
 579         for (sp = name; *sp; *dp++ = *sp++)
 580             if (dp == &path[MAXPATHLEN + 1]) {
 581                 *--dp = '\0';
 582                 break;
 583             }
 584         *dp = '\0';
 585         strname = short2str(path);
 586     }
 587     else
 588         strname = short2str(name);
 589     return (stat(strname, &stbuf) != -1 && ((S_ISREG(stbuf.st_mode) &&
 590         /* save time by not calling access() in the hopeless case */
 591         (stbuf.st_mode & (S_IXOTH | S_IXGRP | S_IXUSR)) &&
 592         access(strname, X_OK) == 0) || (dir_ok && S_ISDIR(stbuf.st_mode))));
 593 }
 594
 595 /* The dowhich() is by:
 596  *  Andreas Luik <luik@isaak.isa.de>
 597  *  I S A  GmbH - Informationssysteme fuer computerintegrierte Automatisierung
 598  *  Azenberstr. 35
 599  *  D-7000 Stuttgart 1
 600  *  West-Germany
 601  * Thanks!!
 602  */
 603 /*ARGSUSED*/
 604 void
 605 dowhich(Char **v, struct command *c)
 606 {
 607     struct wordent lexw[3];
 608     struct varent *vp;
 609
 610     lexw[0].next = &lexw[1];
 611     lexw[1].next = &lexw[2];
 612     lexw[2].next = &lexw[0];
 613
 614     lexw[0].prev = &lexw[2];
 615     lexw[1].prev = &lexw[0];
 616     lexw[2].prev = &lexw[1];
 617
 618     lexw[0].word = STRNULL;
 619     lexw[2].word = STRret;
 620
 621     while (*++v) {
 622         if ((vp = adrof1(*v, &aliases)) != NULL) {
 623             (void)fprintf(cshout, "%s: \t aliased to ", vis_str(*v));
 624             blkpr(cshout, vp->vec);
 625             (void)fputc('\n', cshout);
 626             set(STRstatus, Strsave(STR0));
 627         }
 628         else {
 629             lexw[1].word = *v;
 630             set(STRstatus, Strsave(tellmewhat(lexw, NULL) ? STR0 : STR1));
 631         }
 632     }
 633 }
 634
 635 static int
 636 tellmewhat(struct wordent *lexp, Char *str)
 637 {
 638     struct biltins *bptr;
 639     struct wordent *sp;
 640     Char *cmd, *s0, *s1, *s2;
 641     int i;
 642     int aliased, found;
 643     Char qc;
 644
 645     aliased = 0;
 646     sp = lexp->next;
 647
 648     if (adrof1(sp->word, &aliases)) {
 649         alias(lexp);
 650         sp = lexp->next;
 651         aliased = 1;
 652     }
 653
 654     s0 = sp->word;              /* to get the memory freeing right... */
 655
 656     /* handle quoted alias hack */
 657     if ((*(sp->word) & (QUOTE | TRIM)) == QUOTE)
 658         (sp->word)++;
 659
 660     /* do quoting, if it hasn't been done */
 661     s1 = s2 = sp->word;
 662     while (*s2)
 663         switch (*s2) {
 664         case '\'':
 665         case '"':
 666             qc = *s2++;
 667             while (*s2 && *s2 != qc)
 668                 *s1++ = *s2++ | QUOTE;
 669             if (*s2)
 670                 s2++;
 671             break;
 672         case '\\':
 673             if (*++s2)
 674                 *s1++ = *s2++ | QUOTE;
 675             break;
 676         default:
 677             *s1++ = *s2++;
 678         }
 679     *s1 = '\0';
 680
 681     for (bptr = bfunc; bptr < &bfunc[nbfunc]; bptr++) {
 682         if (eq(sp->word, str2short(bptr->bname))) {
 683             if (str == NULL) {
 684                 if (aliased)
 685                     prlex(cshout, lexp);
 686                 (void)fprintf(cshout, "%s: shell built-in command.\n",
 687                                vis_str(sp->word));
 688             }
 689             else
 690                 (void)Strcpy(str, sp->word);
 691             sp->word = s0;      /* we save and then restore this */
 692             return 1;
 693         }
 694     }
 695
 696     sp->word = cmd = globone(sp->word, G_IGNORE);
 697
 698     if ((i = iscommand(sp->word)) != 0) {
 699         Char **pv;
 700         struct varent *v;
 701         int    slash = any(short2str(sp->word), '/');
 702
 703         v = adrof(STRpath);
 704         if (v == 0 || v->vec[0] == 0 || slash)
 705             pv = justabs;
 706         else
 707             pv = v->vec;
 708
 709         while (--i)
 710             pv++;
 711         if (pv[0][0] == 0 || eq(pv[0], STRdot)) {
 712             if (!slash) {
 713                 sp->word = Strspl(STRdotsl, sp->word);
 714                 prlex(cshout, lexp);
 715                 xfree((ptr_t) sp->word);
 716             }
 717             else
 718                 prlex(cshout, lexp);
 719         }
 720         else {
 721             s1 = Strspl(*pv, STRslash);
 722             sp->word = Strspl(s1, sp->word);
 723             xfree((ptr_t) s1);
 724             if (str == NULL)
 725                 prlex(cshout, lexp);
 726             else
 727                 (void)Strcpy(str, sp->word);
 728             xfree((ptr_t) sp->word);
 729         }
 730         found = 1;
 731     }
 732     else {
 733         if (str == NULL) {
 734             if (aliased)
 735                 prlex(cshout, lexp);
 736             (void)fprintf(csherr,
 737                            "%s: Command not found.\n", vis_str(sp->word));
 738         }
 739         else
 740             (void)Strcpy(str, sp->word);
 741         found = 0;
 742     }
 743     sp->word = s0;              /* we save and then restore this */
 744     xfree((ptr_t) cmd);
 745     return found;
 746 }