bin/sh/exec.c

   1 /*-
   2  * Copyright (c) 1991, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * This code is derived from software contributed to Berkeley by
   6  * Kenneth Almquist.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the name of the University nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 #ifndef lint
  34 #if 0
  35 static char sccsid[] = "@(#)exec.c      8.4 (Berkeley) 6/8/95";
  36 #endif
  37 #endif /* not lint */
  38 #include <sys/cdefs.h>
  39 __FBSDID("$FreeBSD: head/bin/sh/exec.c 365037 2020-09-01 13:19:15Z jilles $");
  40
  41 #include <sys/types.h>
  42 #include <sys/stat.h>
  43 #include <unistd.h>
  44 #include <fcntl.h>
  45 #include <errno.h>
  46 #include <paths.h>
  47 #include <stdbool.h>
  48 #include <stdlib.h>
  49
  50 /*
  51  * When commands are first encountered, they are entered in a hash table.
  52  * This ensures that a full path search will not have to be done for them
  53  * on each invocation.
  54  *
  55  * We should investigate converting to a linear search, even though that
  56  * would make the command name "hash" a misnomer.
  57  */
  58
  59 #include "shell.h"
  60 #include "main.h"
  61 #include "nodes.h"
  62 #include "parser.h"
  63 #include "redir.h"
  64 #include "eval.h"
  65 #include "exec.h"
  66 #include "builtins.h"
  67 #include "var.h"
  68 #include "options.h"
  69 #include "input.h"
  70 #include "output.h"
  71 #include "syntax.h"
  72 #include "memalloc.h"
  73 #include "error.h"
  74 #include "mystring.h"
  75 #include "show.h"
  76 #include "jobs.h"
  77 #include "alias.h"
  78
  79
  80 #define CMDTABLESIZE 31         /* should be prime */
  81
  82
  83
  84 struct tblentry {
  85         struct tblentry *next;  /* next entry in hash chain */
  86         union param param;      /* definition of builtin function */
  87         int special;            /* flag for special builtin commands */
  88         signed char cmdtype;    /* index identifying command */
  89         char cmdname[];         /* name of command */
  90 };
  91
  92
  93 static struct tblentry *cmdtable[CMDTABLESIZE];
  94 static int cmdtable_cd = 0;     /* cmdtable contains cd-dependent entries */
  95
  96
  97 static void tryexec(char *, char **, char **);
  98 static void printentry(struct tblentry *, int);
  99 static struct tblentry *cmdlookup(const char *, int);
 100 static void delete_cmd_entry(void);
 101 static void addcmdentry(const char *, struct cmdentry *);
 102
 103
 104
 105 /*
 106  * Exec a program.  Never returns.  If you change this routine, you may
 107  * have to change the find_command routine as well.
 108  *
 109  * The argv array may be changed and element argv[-1] should be writable.
 110  */
 111
 112 void
 113 shellexec(char **argv, char **envp, const char *path, int idx)
 114 {
 115         char *cmdname;
 116         const char *opt;
 117         int e;
 118
 119         if (strchr(argv[0], '/') != NULL) {
 120                 tryexec(argv[0], argv, envp);
 121                 e = errno;
 122         } else {
 123                 e = ENOENT;
 124                 while ((cmdname = padvance(&path, &opt, argv[0])) != NULL) {
 125                         if (--idx < 0 && opt == NULL) {
 126                                 tryexec(cmdname, argv, envp);
 127                                 if (errno != ENOENT && errno != ENOTDIR)
 128                                         e = errno;
 129                                 if (e == ENOEXEC)
 130                                         break;
 131                         }
 132                         stunalloc(cmdname);
 133                 }
 134         }
 135
 136         /* Map to POSIX errors */
 137         if (e == ENOENT || e == ENOTDIR)
 138                 errorwithstatus(127, "%s: not found", argv[0]);
 139         else
 140                 errorwithstatus(126, "%s: %s", argv[0], strerror(e));
 141 }
 142
 143
 144 static bool
 145 isbinary(const char *data, size_t len)
 146 {
 147         const char *nul, *p;
 148         bool hasletter;
 149
 150         nul = memchr(data, '\0', len);
 151         if (nul == NULL)
 152                 return false;
 153         /*
 154          * POSIX says we shall allow execution if the initial part intended
 155          * to be parsed by the shell consists of characters and does not
 156          * contain the NUL character. This allows concatenating a shell
 157          * script (ending with exec or exit) and a binary payload.
 158          *
 159          * In order to reject common binary files such as PNG images, check
 160          * that there is a lowercase letter or expansion before the last
 161          * newline before the NUL character, in addition to the check for
 162          * the newline character suggested by POSIX.
 163          */
 164         hasletter = false;
 165         for (p = data; *p != '\0'; p++) {
 166                 if ((*p >= 'a' && *p <= 'z') || *p == '$' || *p == '`')
 167                         hasletter = true;
 168                 if (hasletter && *p == '\n')
 169                         return false;
 170         }
 171         return true;
 172 }
 173
 174
 175 static void
 176 tryexec(char *cmd, char **argv, char **envp)
 177 {
 178         int e, in;
 179         ssize_t n;
 180         char buf[256];
 181
 182         execve(cmd, argv, envp);
 183         e = errno;
 184         if (e == ENOEXEC) {
 185                 INTOFF;
 186                 in = open(cmd, O_RDONLY | O_NONBLOCK);
 187                 if (in != -1) {
 188                         n = pread(in, buf, sizeof buf, 0);
 189                         close(in);
 190                         if (n > 0 && isbinary(buf, n)) {
 191                                 errno = ENOEXEC;
 192                                 return;
 193                         }
 194                 }
 195                 *argv = cmd;
 196                 *--argv = __DECONST(char *, _PATH_BSHELL);
 197                 execve(_PATH_BSHELL, argv, envp);
 198         }
 199         errno = e;
 200 }
 201
 202 /*
 203  * Do a path search.  The variable path (passed by reference) should be
 204  * set to the start of the path before the first call; padvance will update
 205  * this value as it proceeds.  Successive calls to padvance will return
 206  * the possible path expansions in sequence.  If popt is not NULL, options
 207  * are processed: if an option (indicated by a percent sign) appears in
 208  * the path entry then *popt will be set to point to it; else *popt will be
 209  * set to NULL.  If popt is NULL, percent signs are not special.
 210  */
 211
 212 char *
 213 padvance(const char **path, const char **popt, const char *name)
 214 {
 215         const char *p, *start;
 216         char *q;
 217         size_t len, namelen;
 218
 219         if (*path == NULL)
 220                 return NULL;
 221         start = *path;
 222         if (popt != NULL)
 223                 for (p = start; *p && *p != ':' && *p != '%'; p++)
 224                         ; /* nothing */
 225         else
 226                 for (p = start; *p && *p != ':'; p++)
 227                         ; /* nothing */
 228         namelen = strlen(name);
 229         len = p - start + namelen + 2;  /* "2" is for '/' and '\0' */
 230         STARTSTACKSTR(q);
 231         CHECKSTRSPACE(len, q);
 232         if (p != start) {
 233                 memcpy(q, start, p - start);
 234                 q += p - start;
 235                 *q++ = '/';
 236         }
 237         memcpy(q, name, namelen + 1);
 238         if (popt != NULL) {
 239                 if (*p == '%') {
 240                         *popt = ++p;
 241                         while (*p && *p != ':')  p++;
 242                 } else
 243                         *popt = NULL;
 244         }
 245         if (*p == ':')
 246                 *path = p + 1;
 247         else
 248                 *path = NULL;
 249         return stalloc(len);
 250 }
 251
 252
 253
 254 /*** Command hashing code ***/
 255
 256
 257 int
 258 hashcmd(int argc __unused, char **argv __unused)
 259 {
 260         struct tblentry **pp;
 261         struct tblentry *cmdp;
 262         int c;
 263         int verbose;
 264         struct cmdentry entry;
 265         char *name;
 266         int errors;
 267
 268         errors = 0;
 269         verbose = 0;
 270         while ((c = nextopt("rv")) != '\0') {
 271                 if (c == 'r') {
 272                         clearcmdentry();
 273                 } else if (c == 'v') {
 274                         verbose++;
 275                 }
 276         }
 277         if (*argptr == NULL) {
 278                 for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) {
 279                         for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
 280                                 if (cmdp->cmdtype == CMDNORMAL)
 281                                         printentry(cmdp, verbose);
 282                         }
 283                 }
 284                 return 0;
 285         }
 286         while ((name = *argptr) != NULL) {
 287                 if ((cmdp = cmdlookup(name, 0)) != NULL
 288                  && cmdp->cmdtype == CMDNORMAL)
 289                         delete_cmd_entry();
 290                 find_command(name, &entry, DO_ERR, pathval());
 291                 if (entry.cmdtype == CMDUNKNOWN)
 292                         errors = 1;
 293                 else if (verbose) {
 294                         cmdp = cmdlookup(name, 0);
 295                         if (cmdp != NULL)
 296                                 printentry(cmdp, verbose);
 297                         else {
 298                                 outfmt(out2, "%s: not found\n", name);
 299                                 errors = 1;
 300                         }
 301                         flushall();
 302                 }
 303                 argptr++;
 304         }
 305         return errors;
 306 }
 307
 308
 309 static void
 310 printentry(struct tblentry *cmdp, int verbose)
 311 {
 312         int idx;
 313         const char *path, *opt;
 314         char *name;
 315
 316         if (cmdp->cmdtype == CMDNORMAL) {
 317                 idx = cmdp->param.index;
 318                 path = pathval();
 319                 do {
 320                         name = padvance(&path, &opt, cmdp->cmdname);
 321                         stunalloc(name);
 322                 } while (--idx >= 0);
 323                 out1str(name);
 324         } else if (cmdp->cmdtype == CMDBUILTIN) {
 325                 out1fmt("builtin %s", cmdp->cmdname);
 326         } else if (cmdp->cmdtype == CMDFUNCTION) {
 327                 out1fmt("function %s", cmdp->cmdname);
 328                 if (verbose) {
 329                         INTOFF;
 330                         name = commandtext(getfuncnode(cmdp->param.func));
 331                         out1c(' ');
 332                         out1str(name);
 333                         ckfree(name);
 334                         INTON;
 335                 }
 336 #ifdef DEBUG
 337         } else {
 338                 error("internal error: cmdtype %d", cmdp->cmdtype);
 339 #endif
 340         }
 341         out1c('\n');
 342 }
 343
 344
 345
 346 /*
 347  * Resolve a command name.  If you change this routine, you may have to
 348  * change the shellexec routine as well.
 349  */
 350
 351 void
 352 find_command(const char *name, struct cmdentry *entry, int act,
 353     const char *path)
 354 {
 355         struct tblentry *cmdp, loc_cmd;
 356         int idx;
 357         const char *opt;
 358         char *fullname;
 359         struct stat statb;
 360         int e;
 361         int i;
 362         int spec;
 363         int cd;
 364
 365         /* If name contains a slash, don't use the hash table */
 366         if (strchr(name, '/') != NULL) {
 367                 entry->cmdtype = CMDNORMAL;
 368                 entry->u.index = 0;
 369                 entry->special = 0;
 370                 return;
 371         }
 372
 373         cd = 0;
 374
 375         /* If name is in the table, we're done */
 376         if ((cmdp = cmdlookup(name, 0)) != NULL) {
 377                 if (cmdp->cmdtype == CMDFUNCTION && act & DO_NOFUNC)
 378                         cmdp = NULL;
 379                 else
 380                         goto success;
 381         }
 382
 383         /* Check for builtin next */
 384         if ((i = find_builtin(name, &spec)) >= 0) {
 385                 INTOFF;
 386                 cmdp = cmdlookup(name, 1);
 387                 if (cmdp->cmdtype == CMDFUNCTION)
 388                         cmdp = &loc_cmd;
 389                 cmdp->cmdtype = CMDBUILTIN;
 390                 cmdp->param.index = i;
 391                 cmdp->special = spec;
 392                 INTON;
 393                 goto success;
 394         }
 395
 396         /* We have to search path. */
 397
 398         e = ENOENT;
 399         idx = -1;
 400         for (;(fullname = padvance(&path, &opt, name)) != NULL;
 401             stunalloc(fullname)) {
 402                 idx++;
 403                 if (opt) {
 404                         if (strncmp(opt, "func", 4) == 0) {
 405                                 /* handled below */
 406                         } else {
 407                                 continue; /* ignore unimplemented options */
 408                         }
 409                 }
 410                 if (fullname[0] != '/')
 411                         cd = 1;
 412                 if (stat(fullname, &statb) < 0) {
 413                         if (errno != ENOENT && errno != ENOTDIR)
 414                                 e = errno;
 415                         continue;
 416                 }
 417                 e = EACCES;     /* if we fail, this will be the error */
 418                 if (!S_ISREG(statb.st_mode))
 419                         continue;
 420                 if (opt) {              /* this is a %func directory */
 421                         readcmdfile(fullname);
 422                         if ((cmdp = cmdlookup(name, 0)) == NULL || cmdp->cmdtype != CMDFUNCTION)
 423                                 error("%s not defined in %s", name, fullname);
 424                         stunalloc(fullname);
 425                         goto success;
 426                 }
 427 #ifdef notdef
 428                 if (statb.st_uid == geteuid()) {
 429                         if ((statb.st_mode & 0100) == 0)
 430                                 goto loop;
 431                 } else if (statb.st_gid == getegid()) {
 432                         if ((statb.st_mode & 010) == 0)
 433                                 goto loop;
 434                 } else {
 435                         if ((statb.st_mode & 01) == 0)
 436                                 goto loop;
 437                 }
 438 #endif
 439                 TRACE(("searchexec \"%s\" returns \"%s\"\n", name, fullname));
 440                 INTOFF;
 441                 stunalloc(fullname);
 442                 cmdp = cmdlookup(name, 1);
 443                 if (cmdp->cmdtype == CMDFUNCTION)
 444                         cmdp = &loc_cmd;
 445                 cmdp->cmdtype = CMDNORMAL;
 446                 cmdp->param.index = idx;
 447                 cmdp->special = 0;
 448                 INTON;
 449                 goto success;
 450         }
 451
 452         if (act & DO_ERR) {
 453                 if (e == ENOENT || e == ENOTDIR)
 454                         outfmt(out2, "%s: not found\n", name);
 455                 else
 456                         outfmt(out2, "%s: %s\n", name, strerror(e));
 457         }
 458         entry->cmdtype = CMDUNKNOWN;
 459         entry->u.index = 0;
 460         entry->special = 0;
 461         return;
 462
 463 success:
 464         if (cd)
 465                 cmdtable_cd = 1;
 466         entry->cmdtype = cmdp->cmdtype;
 467         entry->u = cmdp->param;
 468         entry->special = cmdp->special;
 469 }
 470
 471
 472
 473 /*
 474  * Search the table of builtin commands.
 475  */
 476
 477 int
 478 find_builtin(const char *name, int *special)
 479 {
 480         const unsigned char *bp;
 481         size_t len;
 482
 483         len = strlen(name);
 484         for (bp = builtincmd ; *bp ; bp += 2 + bp[0]) {
 485                 if (bp[0] == len && memcmp(bp + 2, name, len) == 0) {
 486                         *special = (bp[1] & BUILTIN_SPECIAL) != 0;
 487                         return bp[1] & ~BUILTIN_SPECIAL;
 488                 }
 489         }
 490         return -1;
 491 }
 492
 493
 494
 495 /*
 496  * Called when a cd is done.  If any entry in cmdtable depends on the current
 497  * directory, simply clear cmdtable completely.
 498  */
 499
 500 void
 501 hashcd(void)
 502 {
 503         if (cmdtable_cd)
 504                 clearcmdentry();
 505 }
 506
 507
 508
 509 /*
 510  * Called before PATH is changed.  The argument is the new value of PATH;
 511  * pathval() still returns the old value at this point.  Called with
 512  * interrupts off.
 513  */
 514
 515 void
 516 changepath(const char *newval __unused)
 517 {
 518         clearcmdentry();
 519 }
 520
 521
 522 /*
 523  * Clear out cached utility locations.
 524  */
 525
 526 void
 527 clearcmdentry(void)
 528 {
 529         struct tblentry **tblp;
 530         struct tblentry **pp;
 531         struct tblentry *cmdp;
 532
 533         INTOFF;
 534         for (tblp = cmdtable ; tblp < &cmdtable[CMDTABLESIZE] ; tblp++) {
 535                 pp = tblp;
 536                 while ((cmdp = *pp) != NULL) {
 537                         if (cmdp->cmdtype == CMDNORMAL) {
 538                                 *pp = cmdp->next;
 539                                 ckfree(cmdp);
 540                         } else {
 541                                 pp = &cmdp->next;
 542                         }
 543                 }
 544         }
 545         cmdtable_cd = 0;
 546         INTON;
 547 }
 548
 549
 550 /*
 551  * Locate a command in the command hash table.  If "add" is nonzero,
 552  * add the command to the table if it is not already present.  The
 553  * variable "lastcmdentry" is set to point to the address of the link
 554  * pointing to the entry, so that delete_cmd_entry can delete the
 555  * entry.
 556  */
 557
 558 static struct tblentry **lastcmdentry;
 559
 560
 561 static struct tblentry *
 562 cmdlookup(const char *name, int add)
 563 {
 564         unsigned int hashval;
 565         const char *p;
 566         struct tblentry *cmdp;
 567         struct tblentry **pp;
 568         size_t len;
 569
 570         p = name;
 571         hashval = (unsigned char)*p << 4;
 572         while (*p)
 573                 hashval += *p++;
 574         pp = &cmdtable[hashval % CMDTABLESIZE];
 575         for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
 576                 if (equal(cmdp->cmdname, name))
 577                         break;
 578                 pp = &cmdp->next;
 579         }
 580         if (add && cmdp == NULL) {
 581                 INTOFF;
 582                 len = strlen(name);
 583                 cmdp = *pp = ckmalloc(sizeof (struct tblentry) + len + 1);
 584                 cmdp->next = NULL;
 585                 cmdp->cmdtype = CMDUNKNOWN;
 586                 memcpy(cmdp->cmdname, name, len + 1);
 587                 INTON;
 588         }
 589         lastcmdentry = pp;
 590         return cmdp;
 591 }
 592
 593 /*
 594  * Delete the command entry returned on the last lookup.
 595  */
 596
 597 static void
 598 delete_cmd_entry(void)
 599 {
 600         struct tblentry *cmdp;
 601
 602         INTOFF;
 603         cmdp = *lastcmdentry;
 604         *lastcmdentry = cmdp->next;
 605         ckfree(cmdp);
 606         INTON;
 607 }
 608
 609
 610
 611 /*
 612  * Add a new command entry, replacing any existing command entry for
 613  * the same name.
 614  */
 615
 616 static void
 617 addcmdentry(const char *name, struct cmdentry *entry)
 618 {
 619         struct tblentry *cmdp;
 620
 621         INTOFF;
 622         cmdp = cmdlookup(name, 1);
 623         if (cmdp->cmdtype == CMDFUNCTION) {
 624                 unreffunc(cmdp->param.func);
 625         }
 626         cmdp->cmdtype = entry->cmdtype;
 627         cmdp->param = entry->u;
 628         cmdp->special = entry->special;
 629         INTON;
 630 }
 631
 632
 633 /*
 634  * Define a shell function.
 635  */
 636
 637 void
 638 defun(const char *name, union node *func)
 639 {
 640         struct cmdentry entry;
 641
 642         INTOFF;
 643         entry.cmdtype = CMDFUNCTION;
 644         entry.u.func = copyfunc(func);
 645         entry.special = 0;
 646         addcmdentry(name, &entry);
 647         INTON;
 648 }
 649
 650
 651 /*
 652  * Delete a function if it exists.
 653  * Called with interrupts off.
 654  */
 655
 656 int
 657 unsetfunc(const char *name)
 658 {
 659         struct tblentry *cmdp;
 660
 661         if ((cmdp = cmdlookup(name, 0)) != NULL && cmdp->cmdtype == CMDFUNCTION) {
 662                 unreffunc(cmdp->param.func);
 663                 delete_cmd_entry();
 664                 return (0);
 665         }
 666         return (0);
 667 }
 668
 669
 670 /*
 671  * Check if a function by a certain name exists.
 672  */
 673 int
 674 isfunc(const char *name)
 675 {
 676         struct tblentry *cmdp;
 677         cmdp = cmdlookup(name, 0);
 678         return (cmdp != NULL && cmdp->cmdtype == CMDFUNCTION);
 679 }
 680
 681
 682 static void
 683 print_absolute_path(const char *name)
 684 {
 685         const char *pwd;
 686
 687         if (*name != '/' && (pwd = lookupvar("PWD")) != NULL && *pwd != '\0') {
 688                 out1str(pwd);
 689                 if (strcmp(pwd, "/") != 0)
 690                         outcslow('/', out1);
 691         }
 692         out1str(name);
 693         outcslow('\n', out1);
 694 }
 695
 696
 697 /*
 698  * Shared code for the following builtin commands:
 699  *    type, command -v, command -V
 700  */
 701
 702 int
 703 typecmd_impl(int argc, char **argv, int cmd, const char *path)
 704 {
 705         struct cmdentry entry;
 706         struct tblentry *cmdp;
 707         const char *const *pp;
 708         struct alias *ap;
 709         int i;
 710         int error1 = 0;
 711
 712         if (path != pathval())
 713                 clearcmdentry();
 714
 715         for (i = 1; i < argc; i++) {
 716                 /* First look at the keywords */
 717                 for (pp = parsekwd; *pp; pp++)
 718                         if (**pp == *argv[i] && equal(*pp, argv[i]))
 719                                 break;
 720
 721                 if (*pp) {
 722                         if (cmd == TYPECMD_SMALLV)
 723                                 out1fmt("%s\n", argv[i]);
 724                         else
 725                                 out1fmt("%s is a shell keyword\n", argv[i]);
 726                         continue;
 727                 }
 728
 729                 /* Then look at the aliases */
 730                 if ((ap = lookupalias(argv[i], 1)) != NULL) {
 731                         if (cmd == TYPECMD_SMALLV) {
 732                                 out1fmt("alias %s=", argv[i]);
 733                                 out1qstr(ap->val);
 734                                 outcslow('\n', out1);
 735                         } else
 736                                 out1fmt("%s is an alias for %s\n", argv[i],
 737                                     ap->val);
 738                         continue;
 739                 }
 740
 741                 /* Then check if it is a tracked alias */
 742                 if ((cmdp = cmdlookup(argv[i], 0)) != NULL) {
 743                         entry.cmdtype = cmdp->cmdtype;
 744                         entry.u = cmdp->param;
 745                         entry.special = cmdp->special;
 746                 }
 747                 else {
 748                         /* Finally use brute force */
 749                         find_command(argv[i], &entry, 0, path);
 750                 }
 751
 752                 switch (entry.cmdtype) {
 753                 case CMDNORMAL: {
 754                         if (strchr(argv[i], '/') == NULL) {
 755                                 const char *path2 = path;
 756                                 const char *opt2;
 757                                 char *name;
 758                                 int j = entry.u.index;
 759                                 do {
 760                                         name = padvance(&path2, &opt2, argv[i]);
 761                                         stunalloc(name);
 762                                 } while (--j >= 0);
 763                                 if (cmd != TYPECMD_SMALLV)
 764                                         out1fmt("%s is%s ", argv[i],
 765                                             (cmdp && cmd == TYPECMD_TYPE) ?
 766                                                 " a tracked alias for" : "");
 767                                 print_absolute_path(name);
 768                         } else {
 769                                 if (eaccess(argv[i], X_OK) == 0) {
 770                                         if (cmd != TYPECMD_SMALLV)
 771                                                 out1fmt("%s is ", argv[i]);
 772                                         print_absolute_path(argv[i]);
 773                                 } else {
 774                                         if (cmd != TYPECMD_SMALLV)
 775                                                 outfmt(out2, "%s: %s\n",
 776                                                     argv[i], strerror(errno));
 777                                         error1 |= 127;
 778                                 }
 779                         }
 780                         break;
 781                 }
 782                 case CMDFUNCTION:
 783                         if (cmd == TYPECMD_SMALLV)
 784                                 out1fmt("%s\n", argv[i]);
 785                         else
 786                                 out1fmt("%s is a shell function\n", argv[i]);
 787                         break;
 788
 789                 case CMDBUILTIN:
 790                         if (cmd == TYPECMD_SMALLV)
 791                                 out1fmt("%s\n", argv[i]);
 792                         else if (entry.special)
 793                                 out1fmt("%s is a special shell builtin\n",
 794                                     argv[i]);
 795                         else
 796                                 out1fmt("%s is a shell builtin\n", argv[i]);
 797                         break;
 798
 799                 default:
 800                         if (cmd != TYPECMD_SMALLV)
 801                                 outfmt(out2, "%s: not found\n", argv[i]);
 802                         error1 |= 127;
 803                         break;
 804                 }
 805         }
 806
 807         if (path != pathval())
 808                 clearcmdentry();
 809
 810         return error1;
 811 }
 812
 813 /*
 814  * Locate and print what a word is...
 815  */
 816
 817 int
 818 typecmd(int argc, char **argv)
 819 {
 820         if (argc > 2 && strcmp(argv[1], "--") == 0)
 821                 argc--, argv++;
 822         return typecmd_impl(argc, argv, TYPECMD_TYPE, bltinlookup("PATH", 1));
 823 }