| 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 1.55 2012/02/11 21:06:45 jilles Exp $ |
| 38 | */ |
| 39 | |
| 40 | #include <sys/types.h> |
| 41 | #include <sys/stat.h> |
| 42 | #include <unistd.h> |
| 43 | #include <fcntl.h> |
| 44 | #include <errno.h> |
| 45 | #include <paths.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 | int exerrno = 0; /* Last exec error */ |
| 96 | |
| 97 | |
| 98 | static void tryexec(char *, char **, char **); |
| 99 | static void printentry(struct tblentry *, int); |
| 100 | static struct tblentry *cmdlookup(const char *, int); |
| 101 | static void delete_cmd_entry(void); |
| 102 | static void addcmdentry(const char *, struct cmdentry *); |
| 103 | |
| 104 | /* |
| 105 | * Exec a program. Never returns. If you change this routine, you may |
| 106 | * have to change the find_command routine as well. |
| 107 | * |
| 108 | * The argv array may be changed and element argv[-1] should be writable. |
| 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 | if (e == ENOEXEC) |
| 128 | break; |
| 129 | } |
| 130 | stunalloc(cmdname); |
| 131 | } |
| 132 | } |
| 133 | |
| 134 | /* Map to POSIX errors */ |
| 135 | if (e == ENOENT || e == ENOTDIR) { |
| 136 | exerrno = 127; |
| 137 | exerror(EXEXEC, "%s: not found", argv[0]); |
| 138 | } else { |
| 139 | exerrno = 126; |
| 140 | exerror(EXEXEC, "%s: %s", argv[0], strerror(e)); |
| 141 | } |
| 142 | } |
| 143 | |
| 144 | |
| 145 | static void |
| 146 | tryexec(char *cmd, char **argv, char **envp) |
| 147 | { |
| 148 | int e, in; |
| 149 | ssize_t n; |
| 150 | char buf[256]; |
| 151 | |
| 152 | execve(cmd, argv, envp); |
| 153 | e = errno; |
| 154 | if (e == ENOEXEC) { |
| 155 | INTOFF; |
| 156 | in = open(cmd, O_RDONLY | O_NONBLOCK); |
| 157 | if (in != -1) { |
| 158 | n = pread(in, buf, sizeof buf, 0); |
| 159 | close(in); |
| 160 | if (n > 0 && memchr(buf, '\0', n) != NULL) { |
| 161 | errno = ENOEXEC; |
| 162 | return; |
| 163 | } |
| 164 | } |
| 165 | *argv = cmd; |
| 166 | *--argv = __DECONST(char *, _PATH_BSHELL); |
| 167 | execve(_PATH_BSHELL, argv, envp); |
| 168 | } |
| 169 | errno = e; |
| 170 | } |
| 171 | |
| 172 | /* |
| 173 | * Do a path search. The variable path (passed by reference) should be |
| 174 | * set to the start of the path before the first call; padvance will update |
| 175 | * this value as it proceeds. Successive calls to padvance will return |
| 176 | * the possible path expansions in sequence. If an option (indicated by |
| 177 | * a percent sign) appears in the path entry then the global variable |
| 178 | * pathopt will be set to point to it; otherwise pathopt will be set to |
| 179 | * NULL. |
| 180 | */ |
| 181 | |
| 182 | const char *pathopt; |
| 183 | |
| 184 | char * |
| 185 | padvance(const char **path, const char *name) |
| 186 | { |
| 187 | const char *p, *start; |
| 188 | char *q; |
| 189 | int len; |
| 190 | |
| 191 | if (*path == NULL) |
| 192 | return NULL; |
| 193 | start = *path; |
| 194 | for (p = start; *p && *p != ':' && *p != '%'; p++) |
| 195 | ; /* nothing */ |
| 196 | len = p - start + strlen(name) + 2; /* "2" is for '/' and '\0' */ |
| 197 | STARTSTACKSTR(q); |
| 198 | CHECKSTRSPACE(len, q); |
| 199 | if (p != start) { |
| 200 | memcpy(q, start, p - start); |
| 201 | q += p - start; |
| 202 | *q++ = '/'; |
| 203 | } |
| 204 | strcpy(q, name); |
| 205 | pathopt = NULL; |
| 206 | if (*p == '%') { |
| 207 | pathopt = ++p; |
| 208 | while (*p && *p != ':') p++; |
| 209 | } |
| 210 | if (*p == ':') |
| 211 | *path = p + 1; |
| 212 | else |
| 213 | *path = NULL; |
| 214 | return stalloc(len); |
| 215 | } |
| 216 | |
| 217 | |
| 218 | |
| 219 | /*** Command hashing code ***/ |
| 220 | |
| 221 | |
| 222 | int |
| 223 | hashcmd(int argc __unused, char **argv __unused) |
| 224 | { |
| 225 | struct tblentry **pp; |
| 226 | struct tblentry *cmdp; |
| 227 | int c; |
| 228 | int verbose; |
| 229 | struct cmdentry entry; |
| 230 | char *name; |
| 231 | int errors; |
| 232 | |
| 233 | errors = 0; |
| 234 | verbose = 0; |
| 235 | while ((c = nextopt("rv")) != '\0') { |
| 236 | if (c == 'r') { |
| 237 | clearcmdentry(); |
| 238 | } else if (c == 'v') { |
| 239 | verbose++; |
| 240 | } |
| 241 | } |
| 242 | if (*argptr == NULL) { |
| 243 | for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) { |
| 244 | for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) { |
| 245 | if (cmdp->cmdtype == CMDNORMAL) |
| 246 | printentry(cmdp, verbose); |
| 247 | } |
| 248 | } |
| 249 | return 0; |
| 250 | } |
| 251 | while ((name = *argptr) != NULL) { |
| 252 | if ((cmdp = cmdlookup(name, 0)) != NULL |
| 253 | && cmdp->cmdtype == CMDNORMAL) |
| 254 | delete_cmd_entry(); |
| 255 | find_command(name, &entry, DO_ERR, pathval()); |
| 256 | if (entry.cmdtype == CMDUNKNOWN) |
| 257 | errors = 1; |
| 258 | else if (verbose) { |
| 259 | cmdp = cmdlookup(name, 0); |
| 260 | if (cmdp != NULL) |
| 261 | printentry(cmdp, verbose); |
| 262 | else { |
| 263 | outfmt(out2, "%s: not found\n", name); |
| 264 | errors = 1; |
| 265 | } |
| 266 | flushall(); |
| 267 | } |
| 268 | argptr++; |
| 269 | } |
| 270 | return errors; |
| 271 | } |
| 272 | |
| 273 | |
| 274 | static void |
| 275 | printentry(struct tblentry *cmdp, int verbose) |
| 276 | { |
| 277 | int idx; |
| 278 | const char *path; |
| 279 | char *name; |
| 280 | |
| 281 | if (cmdp->cmdtype == CMDNORMAL) { |
| 282 | idx = cmdp->param.index; |
| 283 | path = pathval(); |
| 284 | do { |
| 285 | name = padvance(&path, cmdp->cmdname); |
| 286 | stunalloc(name); |
| 287 | } while (--idx >= 0); |
| 288 | out1str(name); |
| 289 | } else if (cmdp->cmdtype == CMDBUILTIN) { |
| 290 | out1fmt("builtin %s", cmdp->cmdname); |
| 291 | } else if (cmdp->cmdtype == CMDFUNCTION) { |
| 292 | out1fmt("function %s", cmdp->cmdname); |
| 293 | if (verbose) { |
| 294 | INTOFF; |
| 295 | name = commandtext(getfuncnode(cmdp->param.func)); |
| 296 | out1c(' '); |
| 297 | out1str(name); |
| 298 | ckfree(name); |
| 299 | INTON; |
| 300 | } |
| 301 | #ifdef DEBUG |
| 302 | } else { |
| 303 | error("internal error: cmdtype %d", cmdp->cmdtype); |
| 304 | #endif |
| 305 | } |
| 306 | if (cmdp->rehash) |
| 307 | out1c('*'); |
| 308 | out1c('\n'); |
| 309 | } |
| 310 | |
| 311 | |
| 312 | |
| 313 | /* |
| 314 | * Resolve a command name. If you change this routine, you may have to |
| 315 | * change the shellexec routine as well. |
| 316 | */ |
| 317 | |
| 318 | void |
| 319 | find_command(const char *name, struct cmdentry *entry, int act, |
| 320 | const char *path) |
| 321 | { |
| 322 | struct tblentry *cmdp, loc_cmd; |
| 323 | int idx; |
| 324 | int prev; |
| 325 | char *fullname; |
| 326 | struct stat statb; |
| 327 | int e; |
| 328 | int i; |
| 329 | int spec; |
| 330 | |
| 331 | /* If name contains a slash, don't use the hash table */ |
| 332 | if (strchr(name, '/') != NULL) { |
| 333 | entry->cmdtype = CMDNORMAL; |
| 334 | entry->u.index = 0; |
| 335 | return; |
| 336 | } |
| 337 | |
| 338 | /* If name is in the table, and not invalidated by cd, we're done */ |
| 339 | if ((cmdp = cmdlookup(name, 0)) != NULL && cmdp->rehash == 0) { |
| 340 | if (cmdp->cmdtype == CMDFUNCTION && act & DO_NOFUNC) |
| 341 | cmdp = NULL; |
| 342 | else |
| 343 | goto success; |
| 344 | } |
| 345 | |
| 346 | /* Check for builtin next */ |
| 347 | if ((i = find_builtin(name, &spec)) >= 0) { |
| 348 | INTOFF; |
| 349 | cmdp = cmdlookup(name, 1); |
| 350 | if (cmdp->cmdtype == CMDFUNCTION) |
| 351 | cmdp = &loc_cmd; |
| 352 | cmdp->cmdtype = CMDBUILTIN; |
| 353 | cmdp->param.index = i; |
| 354 | cmdp->special = spec; |
| 355 | INTON; |
| 356 | goto success; |
| 357 | } |
| 358 | |
| 359 | /* We have to search path. */ |
| 360 | prev = -1; /* where to start */ |
| 361 | if (cmdp) { /* doing a rehash */ |
| 362 | if (cmdp->cmdtype == CMDBUILTIN) |
| 363 | prev = -1; |
| 364 | else |
| 365 | prev = cmdp->param.index; |
| 366 | } |
| 367 | |
| 368 | e = ENOENT; |
| 369 | idx = -1; |
| 370 | loop: |
| 371 | while ((fullname = padvance(&path, name)) != NULL) { |
| 372 | stunalloc(fullname); |
| 373 | idx++; |
| 374 | if (pathopt) { |
| 375 | if (prefix("func", pathopt)) { |
| 376 | /* handled below */ |
| 377 | } else { |
| 378 | goto loop; /* ignore unimplemented options */ |
| 379 | } |
| 380 | } |
| 381 | /* if rehash, don't redo absolute path names */ |
| 382 | if (fullname[0] == '/' && idx <= prev) { |
| 383 | if (idx < prev) |
| 384 | goto loop; |
| 385 | TRACE(("searchexec \"%s\": no change\n", name)); |
| 386 | goto success; |
| 387 | } |
| 388 | if (stat(fullname, &statb) < 0) { |
| 389 | if (errno != ENOENT && errno != ENOTDIR) |
| 390 | e = errno; |
| 391 | goto loop; |
| 392 | } |
| 393 | e = EACCES; /* if we fail, this will be the error */ |
| 394 | if (!S_ISREG(statb.st_mode)) |
| 395 | goto loop; |
| 396 | if (pathopt) { /* this is a %func directory */ |
| 397 | stalloc(strlen(fullname) + 1); |
| 398 | readcmdfile(fullname); |
| 399 | if ((cmdp = cmdlookup(name, 0)) == NULL || cmdp->cmdtype != CMDFUNCTION) |
| 400 | error("%s not defined in %s", name, fullname); |
| 401 | stunalloc(fullname); |
| 402 | goto success; |
| 403 | } |
| 404 | #ifdef notdef |
| 405 | if (statb.st_uid == geteuid()) { |
| 406 | if ((statb.st_mode & 0100) == 0) |
| 407 | goto loop; |
| 408 | } else if (statb.st_gid == getegid()) { |
| 409 | if ((statb.st_mode & 010) == 0) |
| 410 | goto loop; |
| 411 | } else { |
| 412 | if ((statb.st_mode & 01) == 0) |
| 413 | goto loop; |
| 414 | } |
| 415 | #endif |
| 416 | TRACE(("searchexec \"%s\" returns \"%s\"\n", name, fullname)); |
| 417 | INTOFF; |
| 418 | cmdp = cmdlookup(name, 1); |
| 419 | if (cmdp->cmdtype == CMDFUNCTION) |
| 420 | cmdp = &loc_cmd; |
| 421 | cmdp->cmdtype = CMDNORMAL; |
| 422 | cmdp->param.index = idx; |
| 423 | INTON; |
| 424 | goto success; |
| 425 | } |
| 426 | |
| 427 | /* We failed. If there was an entry for this command, delete it */ |
| 428 | if (cmdp && cmdp->cmdtype != CMDFUNCTION) |
| 429 | delete_cmd_entry(); |
| 430 | if (act & DO_ERR) { |
| 431 | if (e == ENOENT || e == ENOTDIR) |
| 432 | outfmt(out2, "%s: not found\n", name); |
| 433 | else |
| 434 | outfmt(out2, "%s: %s\n", name, strerror(e)); |
| 435 | } |
| 436 | entry->cmdtype = CMDUNKNOWN; |
| 437 | entry->u.index = 0; |
| 438 | return; |
| 439 | |
| 440 | success: |
| 441 | if (cmdp) { |
| 442 | cmdp->rehash = 0; |
| 443 | entry->cmdtype = cmdp->cmdtype; |
| 444 | entry->u = cmdp->param; |
| 445 | entry->special = cmdp->special; |
| 446 | } else |
| 447 | entry->cmdtype = CMDUNKNOWN; |
| 448 | } |
| 449 | |
| 450 | |
| 451 | |
| 452 | /* |
| 453 | * Search the table of builtin commands. |
| 454 | */ |
| 455 | |
| 456 | int |
| 457 | find_builtin(const char *name, int *special) |
| 458 | { |
| 459 | const struct builtincmd *bp; |
| 460 | |
| 461 | for (bp = builtincmd ; bp->name ; bp++) { |
| 462 | if (*bp->name == *name && equal(bp->name, name)) { |
| 463 | *special = bp->special; |
| 464 | return bp->code; |
| 465 | } |
| 466 | } |
| 467 | return -1; |
| 468 | } |
| 469 | |
| 470 | |
| 471 | |
| 472 | /* |
| 473 | * Called when a cd is done. Marks all commands so the next time they |
| 474 | * are executed they will be rehashed. |
| 475 | */ |
| 476 | |
| 477 | void |
| 478 | hashcd(void) |
| 479 | { |
| 480 | struct tblentry **pp; |
| 481 | struct tblentry *cmdp; |
| 482 | |
| 483 | for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) { |
| 484 | for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) { |
| 485 | if (cmdp->cmdtype == CMDNORMAL) |
| 486 | cmdp->rehash = 1; |
| 487 | } |
| 488 | } |
| 489 | } |
| 490 | |
| 491 | |
| 492 | |
| 493 | /* |
| 494 | * Called before PATH is changed. The argument is the new value of PATH; |
| 495 | * pathval() still returns the old value at this point. Called with |
| 496 | * interrupts off. |
| 497 | */ |
| 498 | |
| 499 | void |
| 500 | changepath(const char *newval __unused) |
| 501 | { |
| 502 | clearcmdentry(); |
| 503 | } |
| 504 | |
| 505 | |
| 506 | /* |
| 507 | * Clear out command entries. The argument specifies the first entry in |
| 508 | * PATH which has changed. |
| 509 | */ |
| 510 | |
| 511 | void |
| 512 | clearcmdentry(void) |
| 513 | { |
| 514 | struct tblentry **tblp; |
| 515 | struct tblentry **pp; |
| 516 | struct tblentry *cmdp; |
| 517 | |
| 518 | INTOFF; |
| 519 | for (tblp = cmdtable ; tblp < &cmdtable[CMDTABLESIZE] ; tblp++) { |
| 520 | pp = tblp; |
| 521 | while ((cmdp = *pp) != NULL) { |
| 522 | if (cmdp->cmdtype == CMDNORMAL) { |
| 523 | *pp = cmdp->next; |
| 524 | ckfree(cmdp); |
| 525 | } else { |
| 526 | pp = &cmdp->next; |
| 527 | } |
| 528 | } |
| 529 | } |
| 530 | INTON; |
| 531 | } |
| 532 | |
| 533 | |
| 534 | /* |
| 535 | * Locate a command in the command hash table. If "add" is nonzero, |
| 536 | * add the command to the table if it is not already present. The |
| 537 | * variable "lastcmdentry" is set to point to the address of the link |
| 538 | * pointing to the entry, so that delete_cmd_entry can delete the |
| 539 | * entry. |
| 540 | */ |
| 541 | |
| 542 | static struct tblentry **lastcmdentry; |
| 543 | |
| 544 | |
| 545 | static struct tblentry * |
| 546 | cmdlookup(const char *name, int add) |
| 547 | { |
| 548 | int hashval; |
| 549 | const char *p; |
| 550 | struct tblentry *cmdp; |
| 551 | struct tblentry **pp; |
| 552 | |
| 553 | p = name; |
| 554 | hashval = *p << 4; |
| 555 | while (*p) |
| 556 | hashval += *p++; |
| 557 | hashval &= 0x7FFF; |
| 558 | pp = &cmdtable[hashval % CMDTABLESIZE]; |
| 559 | for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) { |
| 560 | if (equal(cmdp->cmdname, name)) |
| 561 | break; |
| 562 | pp = &cmdp->next; |
| 563 | } |
| 564 | if (add && cmdp == NULL) { |
| 565 | INTOFF; |
| 566 | cmdp = *pp = ckmalloc(sizeof (struct tblentry) - ARB |
| 567 | + strlen(name) + 1); |
| 568 | cmdp->next = NULL; |
| 569 | cmdp->cmdtype = CMDUNKNOWN; |
| 570 | cmdp->rehash = 0; |
| 571 | strcpy(cmdp->cmdname, name); |
| 572 | INTON; |
| 573 | } |
| 574 | lastcmdentry = pp; |
| 575 | return cmdp; |
| 576 | } |
| 577 | |
| 578 | /* |
| 579 | * Delete the command entry returned on the last lookup. |
| 580 | */ |
| 581 | |
| 582 | static void |
| 583 | delete_cmd_entry(void) |
| 584 | { |
| 585 | struct tblentry *cmdp; |
| 586 | |
| 587 | INTOFF; |
| 588 | cmdp = *lastcmdentry; |
| 589 | *lastcmdentry = cmdp->next; |
| 590 | ckfree(cmdp); |
| 591 | INTON; |
| 592 | } |
| 593 | |
| 594 | |
| 595 | |
| 596 | /* |
| 597 | * Add a new command entry, replacing any existing command entry for |
| 598 | * the same name. |
| 599 | */ |
| 600 | |
| 601 | static void |
| 602 | addcmdentry(const char *name, struct cmdentry *entry) |
| 603 | { |
| 604 | struct tblentry *cmdp; |
| 605 | |
| 606 | INTOFF; |
| 607 | cmdp = cmdlookup(name, 1); |
| 608 | if (cmdp->cmdtype == CMDFUNCTION) { |
| 609 | unreffunc(cmdp->param.func); |
| 610 | } |
| 611 | cmdp->cmdtype = entry->cmdtype; |
| 612 | cmdp->param = entry->u; |
| 613 | INTON; |
| 614 | } |
| 615 | |
| 616 | |
| 617 | /* |
| 618 | * Define a shell function. |
| 619 | */ |
| 620 | |
| 621 | void |
| 622 | defun(const char *name, union node *func) |
| 623 | { |
| 624 | struct cmdentry entry; |
| 625 | |
| 626 | INTOFF; |
| 627 | entry.cmdtype = CMDFUNCTION; |
| 628 | entry.u.func = copyfunc(func); |
| 629 | addcmdentry(name, &entry); |
| 630 | INTON; |
| 631 | } |
| 632 | |
| 633 | |
| 634 | /* |
| 635 | * Delete a function if it exists. |
| 636 | */ |
| 637 | |
| 638 | int |
| 639 | unsetfunc(const char *name) |
| 640 | { |
| 641 | struct tblentry *cmdp; |
| 642 | |
| 643 | if ((cmdp = cmdlookup(name, 0)) != NULL && cmdp->cmdtype == CMDFUNCTION) { |
| 644 | unreffunc(cmdp->param.func); |
| 645 | delete_cmd_entry(); |
| 646 | } |
| 647 | return (0); |
| 648 | } |
| 649 | |
| 650 | /* |
| 651 | * Shared code for the following builtin commands: |
| 652 | * type, command -v, command -V |
| 653 | */ |
| 654 | |
| 655 | int |
| 656 | typecmd_impl(int argc, char **argv, int cmd, const char *path) |
| 657 | { |
| 658 | struct cmdentry entry; |
| 659 | struct tblentry *cmdp; |
| 660 | const char * const *pp; |
| 661 | struct alias *ap; |
| 662 | int i; |
| 663 | int err = 0; |
| 664 | |
| 665 | if (path != pathval()) |
| 666 | clearcmdentry(); |
| 667 | |
| 668 | for (i = 1; i < argc; i++) { |
| 669 | /* First look at the keywords */ |
| 670 | for (pp = parsekwd; *pp; pp++) |
| 671 | if (**pp == *argv[i] && equal(*pp, argv[i])) |
| 672 | break; |
| 673 | |
| 674 | if (*pp) { |
| 675 | if (cmd == TYPECMD_SMALLV) |
| 676 | out1fmt("%s\n", argv[i]); |
| 677 | else |
| 678 | out1fmt("%s is a shell keyword\n", argv[i]); |
| 679 | continue; |
| 680 | } |
| 681 | |
| 682 | /* Then look at the aliases */ |
| 683 | if ((ap = lookupalias(argv[i], 1)) != NULL) { |
| 684 | if (cmd == TYPECMD_SMALLV) |
| 685 | out1fmt("alias %s='%s'\n", argv[i], ap->val); |
| 686 | else |
| 687 | out1fmt("%s is an alias for %s\n", argv[i], |
| 688 | ap->val); |
| 689 | continue; |
| 690 | } |
| 691 | |
| 692 | /* Then check if it is a tracked alias */ |
| 693 | if ((cmdp = cmdlookup(argv[i], 0)) != NULL) { |
| 694 | entry.cmdtype = cmdp->cmdtype; |
| 695 | entry.u = cmdp->param; |
| 696 | entry.special = cmdp->special; |
| 697 | } |
| 698 | else { |
| 699 | /* Finally use brute force */ |
| 700 | find_command(argv[i], &entry, 0, path); |
| 701 | } |
| 702 | |
| 703 | switch (entry.cmdtype) { |
| 704 | case CMDNORMAL: { |
| 705 | if (strchr(argv[i], '/') == NULL) { |
| 706 | const char *path2 = path; |
| 707 | char *name; |
| 708 | int j = entry.u.index; |
| 709 | do { |
| 710 | name = padvance(&path2, argv[i]); |
| 711 | stunalloc(name); |
| 712 | } while (--j >= 0); |
| 713 | if (cmd == TYPECMD_SMALLV) |
| 714 | out1fmt("%s\n", name); |
| 715 | else |
| 716 | out1fmt("%s is%s %s\n", argv[i], |
| 717 | (cmdp && cmd == TYPECMD_TYPE) ? |
| 718 | " a tracked alias for" : "", |
| 719 | name); |
| 720 | } else { |
| 721 | if (access(argv[i], X_OK) == 0) { |
| 722 | if (cmd == TYPECMD_SMALLV) |
| 723 | out1fmt("%s\n", argv[i]); |
| 724 | else |
| 725 | out1fmt("%s is %s\n", argv[i], |
| 726 | argv[i]); |
| 727 | } else { |
| 728 | if (cmd != TYPECMD_SMALLV) |
| 729 | outfmt(out2, "%s: %s\n", |
| 730 | argv[i], strerror(errno)); |
| 731 | err |= 127; |
| 732 | } |
| 733 | } |
| 734 | break; |
| 735 | } |
| 736 | case CMDFUNCTION: |
| 737 | if (cmd == TYPECMD_SMALLV) |
| 738 | out1fmt("%s\n", argv[i]); |
| 739 | else |
| 740 | out1fmt("%s is a shell function\n", argv[i]); |
| 741 | break; |
| 742 | |
| 743 | case CMDBUILTIN: |
| 744 | if (cmd == TYPECMD_SMALLV) |
| 745 | out1fmt("%s\n", argv[i]); |
| 746 | else if (entry.special) |
| 747 | out1fmt("%s is a special shell builtin\n", |
| 748 | argv[i]); |
| 749 | else |
| 750 | out1fmt("%s is a shell builtin\n", argv[i]); |
| 751 | break; |
| 752 | |
| 753 | default: |
| 754 | if (cmd != TYPECMD_SMALLV) |
| 755 | outfmt(out2, "%s: not found\n", argv[i]); |
| 756 | err |= 127; |
| 757 | break; |
| 758 | } |
| 759 | } |
| 760 | |
| 761 | if (path != pathval()) |
| 762 | clearcmdentry(); |
| 763 | |
| 764 | return err; |
| 765 | } |
| 766 | |
| 767 | /* |
| 768 | * Locate and print what a word is... |
| 769 | */ |
| 770 | |
| 771 | int |
| 772 | typecmd(int argc, char **argv) |
| 773 | { |
| 774 | return typecmd_impl(argc, argv, TYPECMD_TYPE, bltinlookup("PATH", 1)); |
| 775 | } |