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. All advertising materials mentioning features or use of this software
  17  *    must display the following acknowledgement:
  18  *      This product includes software developed by the University of
  19  *      California, Berkeley and its contributors.
  20  * 4. Neither the name of the University nor the names of its contributors
  21  *    may be used to endorse or promote products derived from this software
  22  *    without specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34  * SUCH DAMAGE.
  35  *
  36  * @(#)exec.c   8.4 (Berkeley) 6/8/95
  37  * $FreeBSD: src/bin/sh/exec.c,v 1.30 2007/01/11 00:19:00 stefanf Exp $
  38  * $DragonFly: src/bin/sh/exec.c,v 1.11 2007/01/14 18:14:39 pavalos Exp $
  39  */
  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 <stdlib.h>
  47
  48 /*
  49  * When commands are first encountered, they are entered in a hash table.
  50  * This ensures that a full path search will not have to be done for them
  51  * on each invocation.
  52  *
  53  * We should investigate converting to a linear search, even though that
  54  * would make the command name "hash" a misnomer.
  55  */
  56
  57 #include "shell.h"
  58 #include "main.h"
  59 #include "nodes.h"
  60 #include "parser.h"
  61 #include "redir.h"
  62 #include "eval.h"
  63 #include "exec.h"
  64 #include "builtins.h"
  65 #include "var.h"
  66 #include "options.h"
  67 #include "input.h"
  68 #include "output.h"
  69 #include "syntax.h"
  70 #include "memalloc.h"
  71 #include "error.h"
  72 #include "init.h"
  73 #include "mystring.h"
  74 #include "show.h"
  75 #include "jobs.h"
  76 #include "alias.h"
  77
  78
  79 #define CMDTABLESIZE 31         /* should be prime */
  80 #define ARB 1                   /* actual size determined at run time */
  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         short cmdtype;          /* index identifying command */
  89         char rehash;            /* if set, cd done since entry created */
  90         char cmdname[ARB];      /* name of command */
  91 };
  92
  93
  94 STATIC struct tblentry *cmdtable[CMDTABLESIZE];
  95 STATIC int builtinloc = -1;             /* index in path of %builtin, or -1 */
  96 int exerrno = 0;                        /* Last exec error */
  97
  98
  99 STATIC void tryexec(char *, char **, char **);
 100 STATIC void printentry(struct tblentry *, int);
 101 STATIC struct tblentry *cmdlookup(char *, int);
 102 STATIC void delete_cmd_entry(void);
 103
 104 extern const char *const parsekwd[];
 105
 106 /*
 107  * Exec a program.  Never returns.  If you change this routine, you may
 108  * have to change the find_command routine as well.
 109  */
 110
 111 void
 112 shellexec(char **argv, char **envp, const char *path, int idx)
 113 {
 114         char *cmdname;
 115         int e;
 116
 117         if (strchr(argv[0], '/') != NULL) {
 118                 tryexec(argv[0], argv, envp);
 119                 e = errno;
 120         } else {
 121                 e = ENOENT;
 122                 while ((cmdname = padvance(&path, argv[0])) != NULL) {
 123                         if (--idx < 0 && pathopt == NULL) {
 124                                 tryexec(cmdname, argv, envp);
 125                                 if (errno != ENOENT && errno != ENOTDIR)
 126                                         e = errno;
 127                         }
 128                         stunalloc(cmdname);
 129                 }
 130         }
 131
 132         /* Map to POSIX errors */
 133         switch (e) {
 134         case EACCES:
 135                 exerrno = 126;
 136                 break;
 137         case ENOENT:
 138                 exerrno = 127;
 139                 break;
 140         default:
 141                 exerrno = 2;
 142                 break;
 143         }
 144         if (e == ENOENT || e == ENOTDIR)
 145                 exerror(EXEXEC, "%s: not found", argv[0]);
 146         exerror(EXEXEC, "%s: %s", argv[0], strerror(e));
 147 }
 148
 149
 150 STATIC void
 151 tryexec(char *cmd, char **argv, char **envp)
 152 {
 153         int e;
 154
 155         execve(cmd, argv, envp);
 156         e = errno;
 157         if (e == ENOEXEC) {
 158                 initshellproc();
 159                 setinputfile(cmd, 0);
 160                 commandname = arg0 = savestr(argv[0]);
 161                 setparam(argv + 1);
 162                 exraise(EXSHELLPROC);
 163                 /*NOTREACHED*/
 164         }
 165         errno = e;
 166 }
 167
 168 /*
 169  * Do a path search.  The variable path (passed by reference) should be
 170  * set to the start of the path before the first call; padvance will update
 171  * this value as it proceeds.  Successive calls to padvance will return
 172  * the possible path expansions in sequence.  If an option (indicated by
 173  * a percent sign) appears in the path entry then the global variable
 174  * pathopt will be set to point to it; otherwise pathopt will be set to
 175  * NULL.
 176  */
 177
 178 const char *pathopt;
 179
 180 char *
 181 padvance(const char **path, const char *name)
 182 {
 183         const char *p;
 184         char *q;
 185         const char *start;
 186         int len;
 187
 188         if (*path == NULL)
 189                 return NULL;
 190         start = *path;
 191         for (p = start ; *p && *p != ':' && *p != '%' ; p++);
 192         len = p - start + strlen(name) + 2;     /* "2" is for '/' and '\0' */
 193         while (stackblocksize() < len)
 194                 growstackblock();
 195         q = stackblock();
 196         if (p != start) {
 197                 memcpy(q, start, p - start);
 198                 q += p - start;
 199                 *q++ = '/';
 200         }
 201         strcpy(q, name);
 202         pathopt = NULL;
 203         if (*p == '%') {
 204                 pathopt = ++p;
 205                 while (*p && *p != ':')  p++;
 206         }
 207         if (*p == ':')
 208                 *path = p + 1;
 209         else
 210                 *path = NULL;
 211         return stalloc(len);
 212 }
 213
 214
 215
 216 /*** Command hashing code ***/
 217
 218
 219 int
 220 hashcmd(int argc __unused, char **argv __unused)
 221 {
 222         struct tblentry **pp;
 223         struct tblentry *cmdp;
 224         int c;
 225         int verbose;
 226         struct cmdentry entry;
 227         char *name;
 228
 229         verbose = 0;
 230         while ((c = nextopt("rv")) != '\0') {
 231                 if (c == 'r') {
 232                         clearcmdentry(0);
 233                 } else if (c == 'v') {
 234                         verbose++;
 235                 }
 236         }
 237         if (*argptr == NULL) {
 238                 for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) {
 239                         for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
 240                                 if (cmdp->cmdtype == CMDNORMAL)
 241                                         printentry(cmdp, verbose);
 242                         }
 243                 }
 244                 return 0;
 245         }
 246         while ((name = *argptr) != NULL) {
 247                 if ((cmdp = cmdlookup(name, 0)) != NULL
 248                  && (cmdp->cmdtype == CMDNORMAL
 249                      || (cmdp->cmdtype == CMDBUILTIN && builtinloc >= 0)))
 250                         delete_cmd_entry();
 251                 find_command(name, &entry, 1, pathval());
 252                 if (verbose) {
 253                         if (entry.cmdtype != CMDUNKNOWN) {      /* if no error msg */
 254                                 cmdp = cmdlookup(name, 0);
 255                                 if (cmdp != NULL)
 256                                         printentry(cmdp, verbose);
 257                                 else
 258                                         outfmt(&errout, "%s: not found\n", name);
 259                         }
 260                         flushall();
 261                 }
 262                 argptr++;
 263         }
 264         return 0;
 265 }
 266
 267
 268 STATIC void
 269 printentry(struct tblentry *cmdp, int verbose)
 270 {
 271         int idx;
 272         const char *path;
 273         char *name;
 274
 275         if (cmdp->cmdtype == CMDNORMAL) {
 276                 idx = cmdp->param.index;
 277                 path = pathval();
 278                 do {
 279                         name = padvance(&path, cmdp->cmdname);
 280                         stunalloc(name);
 281                 } while (--idx >= 0);
 282                 out1str(name);
 283         } else if (cmdp->cmdtype == CMDBUILTIN) {
 284                 out1fmt("builtin %s", cmdp->cmdname);
 285         } else if (cmdp->cmdtype == CMDFUNCTION) {
 286                 out1fmt("function %s", cmdp->cmdname);
 287                 if (verbose) {
 288                         INTOFF;
 289                         name = commandtext(cmdp->param.func);
 290                         out1c(' ');
 291                         out1str(name);
 292                         ckfree(name);
 293                         INTON;
 294                 }
 295 #ifdef DEBUG
 296         } else {
 297                 error("internal error: cmdtype %d", cmdp->cmdtype);
 298 #endif
 299         }
 300         if (cmdp->rehash)
 301                 out1c('*');
 302         out1c('\n');
 303 }
 304
 305
 306
 307 /*
 308  * Resolve a command name.  If you change this routine, you may have to
 309  * change the shellexec routine as well.
 310  */
 311
 312 void
 313 find_command(char *name, struct cmdentry *entry, int printerr, const char *path)
 314 {
 315         struct tblentry *cmdp;
 316         int idx;
 317         int prev;
 318         char *fullname;
 319         struct stat statb;
 320         int e;
 321         int i;
 322         int spec;
 323
 324         /* If name contains a slash, don't use the hash table */
 325         if (strchr(name, '/') != NULL) {
 326                 entry->cmdtype = CMDNORMAL;
 327                 entry->u.index = 0;
 328                 return;
 329         }
 330
 331         /* If name is in the table, and not invalidated by cd, we're done */
 332         if ((cmdp = cmdlookup(name, 0)) != NULL && cmdp->rehash == 0)
 333                 goto success;
 334
 335         /* If %builtin not in path, check for builtin next */
 336         if (builtinloc < 0 && (i = find_builtin(name, &spec)) >= 0) {
 337                 INTOFF;
 338                 cmdp = cmdlookup(name, 1);
 339                 cmdp->cmdtype = CMDBUILTIN;
 340                 cmdp->param.index = i;
 341                 cmdp->special = spec;
 342                 INTON;
 343                 goto success;
 344         }
 345
 346         /* We have to search path. */
 347         prev = -1;              /* where to start */
 348         if (cmdp) {             /* doing a rehash */
 349                 if (cmdp->cmdtype == CMDBUILTIN)
 350                         prev = builtinloc;
 351                 else
 352                         prev = cmdp->param.index;
 353         }
 354
 355         e = ENOENT;
 356         idx = -1;
 357 loop:
 358         while ((fullname = padvance(&path, name)) != NULL) {
 359                 stunalloc(fullname);
 360                 idx++;
 361                 if (pathopt) {
 362                         if (prefix("builtin", pathopt)) {
 363                                 if ((i = find_builtin(name, &spec)) < 0)
 364                                         goto loop;
 365                                 INTOFF;
 366                                 cmdp = cmdlookup(name, 1);
 367                                 cmdp->cmdtype = CMDBUILTIN;
 368                                 cmdp->param.index = i;
 369                                 cmdp->special = spec;
 370                                 INTON;
 371                                 goto success;
 372                         } else if (prefix("func", pathopt)) {
 373                                 /* handled below */
 374                         } else {
 375                                 goto loop;      /* ignore unimplemented options */
 376                         }
 377                 }
 378                 /* if rehash, don't redo absolute path names */
 379                 if (fullname[0] == '/' && idx <= prev) {
 380                         if (idx < prev)
 381                                 goto loop;
 382                         TRACE(("searchexec \"%s\": no change\n", name));
 383                         goto success;
 384                 }
 385                 if (stat(fullname, &statb) < 0) {
 386                         if (errno != ENOENT && errno != ENOTDIR)
 387                                 e = errno;
 388                         goto loop;
 389                 }
 390                 e = EACCES;     /* if we fail, this will be the error */
 391                 if (!S_ISREG(statb.st_mode))
 392                         goto loop;
 393                 if (pathopt) {          /* this is a %func directory */
 394                         stalloc(strlen(fullname) + 1);
 395                         readcmdfile(fullname);
 396                         if ((cmdp = cmdlookup(name, 0)) == NULL || cmdp->cmdtype != CMDFUNCTION)
 397                                 error("%s not defined in %s", name, fullname);
 398                         stunalloc(fullname);
 399                         goto success;
 400                 }
 401 #ifdef notdef
 402                 if (statb.st_uid == geteuid()) {
 403                         if ((statb.st_mode & 0100) == 0)
 404                                 goto loop;
 405                 } else if (statb.st_gid == getegid()) {
 406                         if ((statb.st_mode & 010) == 0)
 407                                 goto loop;
 408                 } else {
 409                         if ((statb.st_mode & 01) == 0)
 410                                 goto loop;
 411                 }
 412 #endif
 413                 TRACE(("searchexec \"%s\" returns \"%s\"\n", name, fullname));
 414                 INTOFF;
 415                 cmdp = cmdlookup(name, 1);
 416                 cmdp->cmdtype = CMDNORMAL;
 417                 cmdp->param.index = idx;
 418                 INTON;
 419                 goto success;
 420         }
 421
 422         /* We failed.  If there was an entry for this command, delete it */
 423         if (cmdp)
 424                 delete_cmd_entry();
 425         if (printerr) {
 426                 if (e == ENOENT || e == ENOTDIR)
 427                         outfmt(out2, "%s: not found\n", name);
 428                 else
 429                         outfmt(out2, "%s: %s\n", name, strerror(e));
 430         }
 431         entry->cmdtype = CMDUNKNOWN;
 432         return;
 433
 434 success:
 435         if (cmdp) {
 436                 cmdp->rehash = 0;
 437                 entry->cmdtype = cmdp->cmdtype;
 438                 entry->u = cmdp->param;
 439                 entry->special = cmdp->special;
 440         } else
 441                 entry->cmdtype = CMDUNKNOWN;
 442 }
 443
 444
 445
 446 /*
 447  * Search the table of builtin commands.
 448  */
 449
 450 int
 451 find_builtin(char *name, int *special)
 452 {
 453         const struct builtincmd *bp;
 454
 455         for (bp = builtincmd ; bp->name ; bp++) {
 456                 if (*bp->name == *name && equal(bp->name, name)) {
 457                         *special = bp->special;
 458                         return bp->code;
 459                 }
 460         }
 461         return -1;
 462 }
 463
 464
 465
 466 /*
 467  * Called when a cd is done.  Marks all commands so the next time they
 468  * are executed they will be rehashed.
 469  */
 470
 471 void
 472 hashcd(void)
 473 {
 474         struct tblentry **pp;
 475         struct tblentry *cmdp;
 476
 477         for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) {
 478                 for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
 479                         if (cmdp->cmdtype == CMDNORMAL
 480                          || (cmdp->cmdtype == CMDBUILTIN && builtinloc >= 0))
 481                                 cmdp->rehash = 1;
 482                 }
 483         }
 484 }
 485
 486
 487
 488 /*
 489  * Called before PATH is changed.  The argument is the new value of PATH;
 490  * pathval() still returns the old value at this point.  Called with
 491  * interrupts off.
 492  */
 493
 494 void
 495 changepath(const char *newval)
 496 {
 497         const char *old, *new;
 498         int idx;
 499         int firstchange;
 500         int bltin;
 501
 502         old = pathval();
 503         new = newval;
 504         firstchange = 9999;     /* assume no change */
 505         idx = 0;
 506         bltin = -1;
 507         for (;;) {
 508                 if (*old != *new) {
 509                         firstchange = idx;
 510                         if ((*old == '\0' && *new == ':')
 511                          || (*old == ':' && *new == '\0'))
 512                                 firstchange++;
 513                         old = new;      /* ignore subsequent differences */
 514                 }
 515                 if (*new == '\0')
 516                         break;
 517                 if (*new == '%' && bltin < 0 && prefix("builtin", new + 1))
 518                         bltin = idx;
 519                 if (*new == ':') {
 520                         idx++;
 521                 }
 522                 new++, old++;
 523         }
 524         if (builtinloc < 0 && bltin >= 0)
 525                 builtinloc = bltin;             /* zap builtins */
 526         if (builtinloc >= 0 && bltin < 0)
 527                 firstchange = 0;
 528         clearcmdentry(firstchange);
 529         builtinloc = bltin;
 530 }
 531
 532
 533 /*
 534  * Clear out command entries.  The argument specifies the first entry in
 535  * PATH which has changed.
 536  */
 537
 538 void
 539 clearcmdentry(int firstchange)
 540 {
 541         struct tblentry **tblp;
 542         struct tblentry **pp;
 543         struct tblentry *cmdp;
 544
 545         INTOFF;
 546         for (tblp = cmdtable ; tblp < &cmdtable[CMDTABLESIZE] ; tblp++) {
 547                 pp = tblp;
 548                 while ((cmdp = *pp) != NULL) {
 549                         if ((cmdp->cmdtype == CMDNORMAL &&
 550                              cmdp->param.index >= firstchange)
 551                          || (cmdp->cmdtype == CMDBUILTIN &&
 552                              builtinloc >= firstchange)) {
 553                                 *pp = cmdp->next;
 554                                 ckfree(cmdp);
 555                         } else {
 556                                 pp = &cmdp->next;
 557                         }
 558                 }
 559         }
 560         INTON;
 561 }
 562
 563
 564 /*
 565  * Delete all functions.
 566  */
 567
 568 #ifdef mkinit
 569 MKINIT void deletefuncs(void);
 570
 571 SHELLPROC {
 572         deletefuncs();
 573 }
 574 #endif
 575
 576 void
 577 deletefuncs(void)
 578 {
 579         struct tblentry **tblp;
 580         struct tblentry **pp;
 581         struct tblentry *cmdp;
 582
 583         INTOFF;
 584         for (tblp = cmdtable ; tblp < &cmdtable[CMDTABLESIZE] ; tblp++) {
 585                 pp = tblp;
 586                 while ((cmdp = *pp) != NULL) {
 587                         if (cmdp->cmdtype == CMDFUNCTION) {
 588                                 *pp = cmdp->next;
 589                                 freefunc(cmdp->param.func);
 590                                 ckfree(cmdp);
 591                         } else {
 592                                 pp = &cmdp->next;
 593                         }
 594                 }
 595         }
 596         INTON;
 597 }
 598
 599
 600
 601 /*
 602  * Locate a command in the command hash table.  If "add" is nonzero,
 603  * add the command to the table if it is not already present.  The
 604  * variable "lastcmdentry" is set to point to the address of the link
 605  * pointing to the entry, so that delete_cmd_entry can delete the
 606  * entry.
 607  */
 608
 609 STATIC struct tblentry **lastcmdentry;
 610
 611
 612 STATIC struct tblentry *
 613 cmdlookup(char *name, int add)
 614 {
 615         int hashval;
 616         char *p;
 617         struct tblentry *cmdp;
 618         struct tblentry **pp;
 619
 620         p = name;
 621         hashval = *p << 4;
 622         while (*p)
 623                 hashval += *p++;
 624         hashval &= 0x7FFF;
 625         pp = &cmdtable[hashval % CMDTABLESIZE];
 626         for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
 627                 if (equal(cmdp->cmdname, name))
 628                         break;
 629                 pp = &cmdp->next;
 630         }
 631         if (add && cmdp == NULL) {
 632                 INTOFF;
 633                 cmdp = *pp = ckmalloc(sizeof (struct tblentry) - ARB
 634                                         + strlen(name) + 1);
 635                 cmdp->next = NULL;
 636                 cmdp->cmdtype = CMDUNKNOWN;
 637                 cmdp->rehash = 0;
 638                 strcpy(cmdp->cmdname, name);
 639                 INTON;
 640         }
 641         lastcmdentry = pp;
 642         return cmdp;
 643 }
 644
 645 /*
 646  * Delete the command entry returned on the last lookup.
 647  */
 648
 649 STATIC void
 650 delete_cmd_entry(void)
 651 {
 652         struct tblentry *cmdp;
 653
 654         INTOFF;
 655         cmdp = *lastcmdentry;
 656         *lastcmdentry = cmdp->next;
 657         ckfree(cmdp);
 658         INTON;
 659 }
 660
 661
 662
 663 /*
 664  * Add a new command entry, replacing any existing command entry for
 665  * the same name.
 666  */
 667
 668 void
 669 addcmdentry(char *name, struct cmdentry *entry)
 670 {
 671         struct tblentry *cmdp;
 672
 673         INTOFF;
 674         cmdp = cmdlookup(name, 1);
 675         if (cmdp->cmdtype == CMDFUNCTION) {
 676                 freefunc(cmdp->param.func);
 677         }
 678         cmdp->cmdtype = entry->cmdtype;
 679         cmdp->param = entry->u;
 680         INTON;
 681 }
 682
 683
 684 /*
 685  * Define a shell function.
 686  */
 687
 688 void
 689 defun(char *name, union node *func)
 690 {
 691         struct cmdentry entry;
 692
 693         INTOFF;
 694         entry.cmdtype = CMDFUNCTION;
 695         entry.u.func = copyfunc(func);
 696         addcmdentry(name, &entry);
 697         INTON;
 698 }
 699
 700
 701 /*
 702  * Delete a function if it exists.
 703  */
 704
 705 int
 706 unsetfunc(char *name)
 707 {
 708         struct tblentry *cmdp;
 709
 710         if ((cmdp = cmdlookup(name, 0)) != NULL && cmdp->cmdtype == CMDFUNCTION) {
 711                 freefunc(cmdp->param.func);
 712                 delete_cmd_entry();
 713         }
 714         return (0);
 715 }
 716
 717 /*
 718  * Shared code for the following builtin commands:
 719  *    type, command -v, command -V
 720  */
 721
 722 int
 723 typecmd_impl(int argc, char **argv, int cmd)
 724 {
 725         struct cmdentry entry;
 726         struct tblentry *cmdp;
 727         const char * const *pp;
 728         struct alias *ap;
 729         int i;
 730         int err = 0;
 731
 732         for (i = 1; i < argc; i++) {
 733                 if (cmd != TYPECMD_SMALLV)
 734                         out1str(argv[i]);
 735
 736                 /* First look at the keywords */
 737                 for (pp = parsekwd; *pp; pp++)
 738                         if (**pp == *argv[i] && equal(*pp, argv[i]))
 739                                 break;
 740
 741                 if (*pp) {
 742                         if (cmd == TYPECMD_SMALLV)
 743                                 out1fmt("%s\n", argv[i]);
 744                         else
 745                                 out1str(" is a shell keyword\n");
 746                         continue;
 747                 }
 748
 749                 /* Then look at the aliases */
 750                 if ((ap = lookupalias(argv[i], 1)) != NULL) {
 751                         if (cmd == TYPECMD_SMALLV)
 752                                 out1fmt("alias %s='%s'\n", argv[i], ap->val);
 753                         else
 754                                 out1fmt(" is an alias for %s\n", ap->val);
 755                         continue;
 756                 }
 757
 758                 /* Then check if it is a tracked alias */
 759                 if ((cmdp = cmdlookup(argv[i], 0)) != NULL) {
 760                         entry.cmdtype = cmdp->cmdtype;
 761                         entry.u = cmdp->param;
 762                 }
 763                 else {
 764                         /* Finally use brute force */
 765                         find_command(argv[i], &entry, 0, pathval());
 766                 }
 767
 768                 switch (entry.cmdtype) {
 769                 case CMDNORMAL: {
 770                         if (strchr(argv[i], '/') == NULL) {
 771                                 const char *path = pathval();
 772                                 char *name;
 773                                 int j = entry.u.index;
 774                                 do {
 775                                         name = padvance(&path, argv[i]);
 776                                         stunalloc(name);
 777                                 } while (--j >= 0);
 778                                 if (cmd == TYPECMD_SMALLV)
 779                                         out1fmt("%s\n", name);
 780                                 else
 781                                         out1fmt(" is%s %s\n",
 782                                             (cmdp && cmd == TYPECMD_TYPE) ?
 783                                                 " a tracked alias for" : "",
 784                                             name);
 785                         } else {
 786                                 if (access(argv[i], X_OK) == 0) {
 787                                         if (cmd == TYPECMD_SMALLV)
 788                                                 out1fmt("%s\n", argv[i]);
 789                                         else
 790                                                 out1fmt(" is %s\n", argv[i]);
 791                                 } else {
 792                                         if (cmd != TYPECMD_SMALLV)
 793                                                 out1fmt(": %s\n",
 794                                                     strerror(errno));
 795                                         err |= 127;
 796                                 }
 797                         }
 798                         break;
 799                 }
 800                 case CMDFUNCTION:
 801                         if (cmd == TYPECMD_SMALLV)
 802                                 out1fmt("%s\n", argv[i]);
 803                         else
 804                                 out1str(" is a shell function\n");
 805                         break;
 806
 807                 case CMDBUILTIN:
 808                         if (cmd == TYPECMD_SMALLV)
 809                                 out1fmt("%s\n", argv[i]);
 810                         else
 811                                 out1str(" is a shell builtin\n");
 812                         break;
 813
 814                 default:
 815                         if (cmd != TYPECMD_SMALLV)
 816                                 out1str(": not found\n");
 817                         err |= 127;
 818                         break;
 819                 }
 820         }
 821         return err;
 822 }
 823
 824 /*
 825  * Locate and print what a word is...
 826  */
 827
 828 int
 829 typecmd(int argc, char **argv)
 830 {
 831         return typecmd_impl(argc, argv, TYPECMD_TYPE);
 832 }