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 * 4. 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
35static char sccsid[] = "@(#)exec.c 8.4 (Berkeley) 6/8/95";
36#endif
37#endif /* not lint */
38#include <sys/cdefs.h>
| 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 * 4. 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
35static 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 194922 2009-06-24 22:04:04Z jilles $");
| 39__FBSDID("$FreeBSD: head/bin/sh/exec.c 196483 2009-08-23 21:09:46Z 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 <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
84struct 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
94STATIC struct tblentry *cmdtable[CMDTABLESIZE];
95STATIC int builtinloc = -1; /* index in path of %builtin, or -1 */
96int exerrno = 0; /* Last exec error */
97
98
99STATIC void tryexec(char *, char **, char **);
100STATIC void printentry(struct tblentry *, int);
101STATIC struct tblentry *cmdlookup(char *, int);
102STATIC void delete_cmd_entry(void);
103
104
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
111void
112shellexec(char **argv, char **envp, char *path, int index)
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 (--index < 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
150STATIC void
151tryexec(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
178char *pathopt;
179
180char *
181padvance(char **path, char *name)
182{
183 char *p, *q;
184 char *start;
185 int len;
186
187 if (*path == NULL)
188 return NULL;
189 start = *path;
190 for (p = start; *p && *p != ':' && *p != '%'; p++)
191 ; /* nothing */
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
219int
220hashcmd(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
268STATIC void
269printentry(struct tblentry *cmdp, int verbose)
270{
271 int index;
272 char *path;
273 char *name;
274
275 if (cmdp->cmdtype == CMDNORMAL) {
276 index = cmdp->param.index;
277 path = pathval();
278 do {
279 name = padvance(&path, cmdp->cmdname);
280 stunalloc(name);
281 } while (--index >= 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;
| 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
84struct 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
94STATIC struct tblentry *cmdtable[CMDTABLESIZE];
95STATIC int builtinloc = -1; /* index in path of %builtin, or -1 */
96int exerrno = 0; /* Last exec error */
97
98
99STATIC void tryexec(char *, char **, char **);
100STATIC void printentry(struct tblentry *, int);
101STATIC struct tblentry *cmdlookup(char *, int);
102STATIC void delete_cmd_entry(void);
103
104
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
111void
112shellexec(char **argv, char **envp, char *path, int index)
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 (--index < 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
150STATIC void
151tryexec(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
178char *pathopt;
179
180char *
181padvance(char **path, char *name)
182{
183 char *p, *q;
184 char *start;
185 int len;
186
187 if (*path == NULL)
188 return NULL;
189 start = *path;
190 for (p = start; *p && *p != ':' && *p != '%'; p++)
191 ; /* nothing */
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
219int
220hashcmd(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
268STATIC void
269printentry(struct tblentry *cmdp, int verbose)
270{
271 int index;
272 char *path;
273 char *name;
274
275 if (cmdp->cmdtype == CMDNORMAL) {
276 index = cmdp->param.index;
277 path = pathval();
278 do {
279 name = padvance(&path, cmdp->cmdname);
280 stunalloc(name);
281 } while (--index >= 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);
| 289 name = commandtext(&cmdp->param.func->n);
|
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
312void
313find_command(char *name, struct cmdentry *entry, int printerr, char *path)
314{
315 struct tblentry *cmdp;
316 int index;
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 index = -1;
357loop:
358 while ((fullname = padvance(&path, name)) != NULL) {
359 stunalloc(fullname);
360 index++;
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] == '/' && index <= prev) {
380 if (index < 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 = index;
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
434success:
435 cmdp->rehash = 0;
436 entry->cmdtype = cmdp->cmdtype;
437 entry->u = cmdp->param;
438 entry->special = cmdp->special;
439}
440
441
442
443/*
444 * Search the table of builtin commands.
445 */
446
447int
448find_builtin(char *name, int *special)
449{
450 const struct builtincmd *bp;
451
452 for (bp = builtincmd ; bp->name ; bp++) {
453 if (*bp->name == *name && equal(bp->name, name)) {
454 *special = bp->special;
455 return bp->code;
456 }
457 }
458 return -1;
459}
460
461
462
463/*
464 * Called when a cd is done. Marks all commands so the next time they
465 * are executed they will be rehashed.
466 */
467
468void
469hashcd(void)
470{
471 struct tblentry **pp;
472 struct tblentry *cmdp;
473
474 for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) {
475 for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
476 if (cmdp->cmdtype == CMDNORMAL
477 || (cmdp->cmdtype == CMDBUILTIN && builtinloc >= 0))
478 cmdp->rehash = 1;
479 }
480 }
481}
482
483
484
485/*
486 * Called before PATH is changed. The argument is the new value of PATH;
487 * pathval() still returns the old value at this point. Called with
488 * interrupts off.
489 */
490
491void
492changepath(const char *newval)
493{
494 const char *old, *new;
495 int index;
496 int firstchange;
497 int bltin;
498
499 old = pathval();
500 new = newval;
501 firstchange = 9999; /* assume no change */
502 index = 0;
503 bltin = -1;
504 for (;;) {
505 if (*old != *new) {
506 firstchange = index;
507 if ((*old == '\0' && *new == ':')
508 || (*old == ':' && *new == '\0'))
509 firstchange++;
510 old = new; /* ignore subsequent differences */
511 }
512 if (*new == '\0')
513 break;
514 if (*new == '%' && bltin < 0 && prefix("builtin", new + 1))
515 bltin = index;
516 if (*new == ':') {
517 index++;
518 }
519 new++, old++;
520 }
521 if (builtinloc < 0 && bltin >= 0)
522 builtinloc = bltin; /* zap builtins */
523 if (builtinloc >= 0 && bltin < 0)
524 firstchange = 0;
525 clearcmdentry(firstchange);
526 builtinloc = bltin;
527}
528
529
530/*
531 * Clear out command entries. The argument specifies the first entry in
532 * PATH which has changed.
533 */
534
535void
536clearcmdentry(int firstchange)
537{
538 struct tblentry **tblp;
539 struct tblentry **pp;
540 struct tblentry *cmdp;
541
542 INTOFF;
543 for (tblp = cmdtable ; tblp < &cmdtable[CMDTABLESIZE] ; tblp++) {
544 pp = tblp;
545 while ((cmdp = *pp) != NULL) {
546 if ((cmdp->cmdtype == CMDNORMAL &&
547 cmdp->param.index >= firstchange)
548 || (cmdp->cmdtype == CMDBUILTIN &&
549 builtinloc >= firstchange)) {
550 *pp = cmdp->next;
551 ckfree(cmdp);
552 } else {
553 pp = &cmdp->next;
554 }
555 }
556 }
557 INTON;
558}
559
560
561/*
562 * Delete all functions.
563 */
564
565#ifdef mkinit
566MKINIT void deletefuncs(void);
567
568SHELLPROC {
569 deletefuncs();
570}
571#endif
572
573void
574deletefuncs(void)
575{
576 struct tblentry **tblp;
577 struct tblentry **pp;
578 struct tblentry *cmdp;
579
580 INTOFF;
581 for (tblp = cmdtable ; tblp < &cmdtable[CMDTABLESIZE] ; tblp++) {
582 pp = tblp;
583 while ((cmdp = *pp) != NULL) {
584 if (cmdp->cmdtype == CMDFUNCTION) {
585 *pp = cmdp->next;
| 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
312void
313find_command(char *name, struct cmdentry *entry, int printerr, char *path)
314{
315 struct tblentry *cmdp;
316 int index;
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 index = -1;
357loop:
358 while ((fullname = padvance(&path, name)) != NULL) {
359 stunalloc(fullname);
360 index++;
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] == '/' && index <= prev) {
380 if (index < 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 = index;
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
434success:
435 cmdp->rehash = 0;
436 entry->cmdtype = cmdp->cmdtype;
437 entry->u = cmdp->param;
438 entry->special = cmdp->special;
439}
440
441
442
443/*
444 * Search the table of builtin commands.
445 */
446
447int
448find_builtin(char *name, int *special)
449{
450 const struct builtincmd *bp;
451
452 for (bp = builtincmd ; bp->name ; bp++) {
453 if (*bp->name == *name && equal(bp->name, name)) {
454 *special = bp->special;
455 return bp->code;
456 }
457 }
458 return -1;
459}
460
461
462
463/*
464 * Called when a cd is done. Marks all commands so the next time they
465 * are executed they will be rehashed.
466 */
467
468void
469hashcd(void)
470{
471 struct tblentry **pp;
472 struct tblentry *cmdp;
473
474 for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) {
475 for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
476 if (cmdp->cmdtype == CMDNORMAL
477 || (cmdp->cmdtype == CMDBUILTIN && builtinloc >= 0))
478 cmdp->rehash = 1;
479 }
480 }
481}
482
483
484
485/*
486 * Called before PATH is changed. The argument is the new value of PATH;
487 * pathval() still returns the old value at this point. Called with
488 * interrupts off.
489 */
490
491void
492changepath(const char *newval)
493{
494 const char *old, *new;
495 int index;
496 int firstchange;
497 int bltin;
498
499 old = pathval();
500 new = newval;
501 firstchange = 9999; /* assume no change */
502 index = 0;
503 bltin = -1;
504 for (;;) {
505 if (*old != *new) {
506 firstchange = index;
507 if ((*old == '\0' && *new == ':')
508 || (*old == ':' && *new == '\0'))
509 firstchange++;
510 old = new; /* ignore subsequent differences */
511 }
512 if (*new == '\0')
513 break;
514 if (*new == '%' && bltin < 0 && prefix("builtin", new + 1))
515 bltin = index;
516 if (*new == ':') {
517 index++;
518 }
519 new++, old++;
520 }
521 if (builtinloc < 0 && bltin >= 0)
522 builtinloc = bltin; /* zap builtins */
523 if (builtinloc >= 0 && bltin < 0)
524 firstchange = 0;
525 clearcmdentry(firstchange);
526 builtinloc = bltin;
527}
528
529
530/*
531 * Clear out command entries. The argument specifies the first entry in
532 * PATH which has changed.
533 */
534
535void
536clearcmdentry(int firstchange)
537{
538 struct tblentry **tblp;
539 struct tblentry **pp;
540 struct tblentry *cmdp;
541
542 INTOFF;
543 for (tblp = cmdtable ; tblp < &cmdtable[CMDTABLESIZE] ; tblp++) {
544 pp = tblp;
545 while ((cmdp = *pp) != NULL) {
546 if ((cmdp->cmdtype == CMDNORMAL &&
547 cmdp->param.index >= firstchange)
548 || (cmdp->cmdtype == CMDBUILTIN &&
549 builtinloc >= firstchange)) {
550 *pp = cmdp->next;
551 ckfree(cmdp);
552 } else {
553 pp = &cmdp->next;
554 }
555 }
556 }
557 INTON;
558}
559
560
561/*
562 * Delete all functions.
563 */
564
565#ifdef mkinit
566MKINIT void deletefuncs(void);
567
568SHELLPROC {
569 deletefuncs();
570}
571#endif
572
573void
574deletefuncs(void)
575{
576 struct tblentry **tblp;
577 struct tblentry **pp;
578 struct tblentry *cmdp;
579
580 INTOFF;
581 for (tblp = cmdtable ; tblp < &cmdtable[CMDTABLESIZE] ; tblp++) {
582 pp = tblp;
583 while ((cmdp = *pp) != NULL) {
584 if (cmdp->cmdtype == CMDFUNCTION) {
585 *pp = cmdp->next;
|
586 freefunc(cmdp->param.func);
| 586 unreffunc(cmdp->param.func);
|
587 ckfree(cmdp);
588 } else {
589 pp = &cmdp->next;
590 }
591 }
592 }
593 INTON;
594}
595
596
597
598/*
599 * Locate a command in the command hash table. If "add" is nonzero,
600 * add the command to the table if it is not already present. The
601 * variable "lastcmdentry" is set to point to the address of the link
602 * pointing to the entry, so that delete_cmd_entry can delete the
603 * entry.
604 */
605
606STATIC struct tblentry **lastcmdentry;
607
608
609STATIC struct tblentry *
610cmdlookup(char *name, int add)
611{
612 int hashval;
613 char *p;
614 struct tblentry *cmdp;
615 struct tblentry **pp;
616
617 p = name;
618 hashval = *p << 4;
619 while (*p)
620 hashval += *p++;
621 hashval &= 0x7FFF;
622 pp = &cmdtable[hashval % CMDTABLESIZE];
623 for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
624 if (equal(cmdp->cmdname, name))
625 break;
626 pp = &cmdp->next;
627 }
628 if (add && cmdp == NULL) {
629 INTOFF;
630 cmdp = *pp = ckmalloc(sizeof (struct tblentry) - ARB
631 + strlen(name) + 1);
632 cmdp->next = NULL;
633 cmdp->cmdtype = CMDUNKNOWN;
634 cmdp->rehash = 0;
635 strcpy(cmdp->cmdname, name);
636 INTON;
637 }
638 lastcmdentry = pp;
639 return cmdp;
640}
641
642/*
643 * Delete the command entry returned on the last lookup.
644 */
645
646STATIC void
647delete_cmd_entry(void)
648{
649 struct tblentry *cmdp;
650
651 INTOFF;
652 cmdp = *lastcmdentry;
653 *lastcmdentry = cmdp->next;
654 ckfree(cmdp);
655 INTON;
656}
657
658
659
660/*
661 * Add a new command entry, replacing any existing command entry for
662 * the same name.
663 */
664
665void
666addcmdentry(char *name, struct cmdentry *entry)
667{
668 struct tblentry *cmdp;
669
670 INTOFF;
671 cmdp = cmdlookup(name, 1);
672 if (cmdp->cmdtype == CMDFUNCTION) {
| 587 ckfree(cmdp);
588 } else {
589 pp = &cmdp->next;
590 }
591 }
592 }
593 INTON;
594}
595
596
597
598/*
599 * Locate a command in the command hash table. If "add" is nonzero,
600 * add the command to the table if it is not already present. The
601 * variable "lastcmdentry" is set to point to the address of the link
602 * pointing to the entry, so that delete_cmd_entry can delete the
603 * entry.
604 */
605
606STATIC struct tblentry **lastcmdentry;
607
608
609STATIC struct tblentry *
610cmdlookup(char *name, int add)
611{
612 int hashval;
613 char *p;
614 struct tblentry *cmdp;
615 struct tblentry **pp;
616
617 p = name;
618 hashval = *p << 4;
619 while (*p)
620 hashval += *p++;
621 hashval &= 0x7FFF;
622 pp = &cmdtable[hashval % CMDTABLESIZE];
623 for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
624 if (equal(cmdp->cmdname, name))
625 break;
626 pp = &cmdp->next;
627 }
628 if (add && cmdp == NULL) {
629 INTOFF;
630 cmdp = *pp = ckmalloc(sizeof (struct tblentry) - ARB
631 + strlen(name) + 1);
632 cmdp->next = NULL;
633 cmdp->cmdtype = CMDUNKNOWN;
634 cmdp->rehash = 0;
635 strcpy(cmdp->cmdname, name);
636 INTON;
637 }
638 lastcmdentry = pp;
639 return cmdp;
640}
641
642/*
643 * Delete the command entry returned on the last lookup.
644 */
645
646STATIC void
647delete_cmd_entry(void)
648{
649 struct tblentry *cmdp;
650
651 INTOFF;
652 cmdp = *lastcmdentry;
653 *lastcmdentry = cmdp->next;
654 ckfree(cmdp);
655 INTON;
656}
657
658
659
660/*
661 * Add a new command entry, replacing any existing command entry for
662 * the same name.
663 */
664
665void
666addcmdentry(char *name, struct cmdentry *entry)
667{
668 struct tblentry *cmdp;
669
670 INTOFF;
671 cmdp = cmdlookup(name, 1);
672 if (cmdp->cmdtype == CMDFUNCTION) {
|
673 freefunc(cmdp->param.func);
| 673 unreffunc(cmdp->param.func);
|
674 }
675 cmdp->cmdtype = entry->cmdtype;
676 cmdp->param = entry->u;
677 INTON;
678}
679
680
681/*
682 * Define a shell function.
683 */
684
685void
686defun(char *name, union node *func)
687{
688 struct cmdentry entry;
689
690 INTOFF;
691 entry.cmdtype = CMDFUNCTION;
692 entry.u.func = copyfunc(func);
693 addcmdentry(name, &entry);
694 INTON;
695}
696
697
698/*
699 * Delete a function if it exists.
700 */
701
702int
703unsetfunc(char *name)
704{
705 struct tblentry *cmdp;
706
707 if ((cmdp = cmdlookup(name, 0)) != NULL && cmdp->cmdtype == CMDFUNCTION) {
| 674 }
675 cmdp->cmdtype = entry->cmdtype;
676 cmdp->param = entry->u;
677 INTON;
678}
679
680
681/*
682 * Define a shell function.
683 */
684
685void
686defun(char *name, union node *func)
687{
688 struct cmdentry entry;
689
690 INTOFF;
691 entry.cmdtype = CMDFUNCTION;
692 entry.u.func = copyfunc(func);
693 addcmdentry(name, &entry);
694 INTON;
695}
696
697
698/*
699 * Delete a function if it exists.
700 */
701
702int
703unsetfunc(char *name)
704{
705 struct tblentry *cmdp;
706
707 if ((cmdp = cmdlookup(name, 0)) != NULL && cmdp->cmdtype == CMDFUNCTION) {
|
708 freefunc(cmdp->param.func);
| 708 unreffunc(cmdp->param.func);
|
709 delete_cmd_entry();
710 return (0);
711 }
712 return (0);
713}
714
715/*
716 * Shared code for the following builtin commands:
717 * type, command -v, command -V
718 */
719
720int
721typecmd_impl(int argc, char **argv, int cmd)
722{
723 struct cmdentry entry;
724 struct tblentry *cmdp;
725 char **pp;
726 struct alias *ap;
727 int i;
728 int error = 0;
729 extern char *const parsekwd[];
730
731 for (i = 1; i < argc; i++) {
732 /* First look at the keywords */
733 for (pp = (char **)parsekwd; *pp; pp++)
734 if (**pp == *argv[i] && equal(*pp, argv[i]))
735 break;
736
737 if (*pp) {
738 if (cmd == TYPECMD_SMALLV)
739 out1fmt("%s\n", argv[i]);
740 else
741 out1fmt("%s is a shell keyword\n", argv[i]);
742 continue;
743 }
744
745 /* Then look at the aliases */
746 if ((ap = lookupalias(argv[i], 1)) != NULL) {
747 if (cmd == TYPECMD_SMALLV)
748 out1fmt("alias %s='%s'\n", argv[i], ap->val);
749 else
750 out1fmt("%s is an alias for %s\n", argv[i],
751 ap->val);
752 continue;
753 }
754
755 /* Then check if it is a tracked alias */
756 if ((cmdp = cmdlookup(argv[i], 0)) != NULL) {
757 entry.cmdtype = cmdp->cmdtype;
758 entry.u = cmdp->param;
759 entry.special = cmdp->special;
760 }
761 else {
762 /* Finally use brute force */
763 find_command(argv[i], &entry, 0, pathval());
764 }
765
766 switch (entry.cmdtype) {
767 case CMDNORMAL: {
768 if (strchr(argv[i], '/') == NULL) {
769 char *path = pathval(), *name;
770 int j = entry.u.index;
771 do {
772 name = padvance(&path, argv[i]);
773 stunalloc(name);
774 } while (--j >= 0);
775 if (cmd == TYPECMD_SMALLV)
776 out1fmt("%s\n", name);
777 else
778 out1fmt("%s is%s %s\n", argv[i],
779 (cmdp && cmd == TYPECMD_TYPE) ?
780 " a tracked alias for" : "",
781 name);
782 } else {
783 if (eaccess(argv[i], X_OK) == 0) {
784 if (cmd == TYPECMD_SMALLV)
785 out1fmt("%s\n", argv[i]);
786 else
787 out1fmt("%s is %s\n", argv[i],
788 argv[i]);
789 } else {
790 if (cmd != TYPECMD_SMALLV)
791 outfmt(out2, "%s: %s\n",
792 argv[i], strerror(errno));
793 error |= 127;
794 }
795 }
796 break;
797 }
798 case CMDFUNCTION:
799 if (cmd == TYPECMD_SMALLV)
800 out1fmt("%s\n", argv[i]);
801 else
802 out1fmt("%s is a shell function\n", argv[i]);
803 break;
804
805 case CMDBUILTIN:
806 if (cmd == TYPECMD_SMALLV)
807 out1fmt("%s\n", argv[i]);
808 else if (entry.special)
809 out1fmt("%s is a special shell builtin\n",
810 argv[i]);
811 else
812 out1fmt("%s is a shell builtin\n", argv[i]);
813 break;
814
815 default:
816 if (cmd != TYPECMD_SMALLV)
817 outfmt(out2, "%s: not found\n", argv[i]);
818 error |= 127;
819 break;
820 }
821 }
822 return error;
823}
824
825/*
826 * Locate and print what a word is...
827 */
828
829int
830typecmd(int argc, char **argv)
831{
832 return typecmd_impl(argc, argv, TYPECMD_TYPE);
833}
| 709 delete_cmd_entry();
710 return (0);
711 }
712 return (0);
713}
714
715/*
716 * Shared code for the following builtin commands:
717 * type, command -v, command -V
718 */
719
720int
721typecmd_impl(int argc, char **argv, int cmd)
722{
723 struct cmdentry entry;
724 struct tblentry *cmdp;
725 char **pp;
726 struct alias *ap;
727 int i;
728 int error = 0;
729 extern char *const parsekwd[];
730
731 for (i = 1; i < argc; i++) {
732 /* First look at the keywords */
733 for (pp = (char **)parsekwd; *pp; pp++)
734 if (**pp == *argv[i] && equal(*pp, argv[i]))
735 break;
736
737 if (*pp) {
738 if (cmd == TYPECMD_SMALLV)
739 out1fmt("%s\n", argv[i]);
740 else
741 out1fmt("%s is a shell keyword\n", argv[i]);
742 continue;
743 }
744
745 /* Then look at the aliases */
746 if ((ap = lookupalias(argv[i], 1)) != NULL) {
747 if (cmd == TYPECMD_SMALLV)
748 out1fmt("alias %s='%s'\n", argv[i], ap->val);
749 else
750 out1fmt("%s is an alias for %s\n", argv[i],
751 ap->val);
752 continue;
753 }
754
755 /* Then check if it is a tracked alias */
756 if ((cmdp = cmdlookup(argv[i], 0)) != NULL) {
757 entry.cmdtype = cmdp->cmdtype;
758 entry.u = cmdp->param;
759 entry.special = cmdp->special;
760 }
761 else {
762 /* Finally use brute force */
763 find_command(argv[i], &entry, 0, pathval());
764 }
765
766 switch (entry.cmdtype) {
767 case CMDNORMAL: {
768 if (strchr(argv[i], '/') == NULL) {
769 char *path = pathval(), *name;
770 int j = entry.u.index;
771 do {
772 name = padvance(&path, argv[i]);
773 stunalloc(name);
774 } while (--j >= 0);
775 if (cmd == TYPECMD_SMALLV)
776 out1fmt("%s\n", name);
777 else
778 out1fmt("%s is%s %s\n", argv[i],
779 (cmdp && cmd == TYPECMD_TYPE) ?
780 " a tracked alias for" : "",
781 name);
782 } else {
783 if (eaccess(argv[i], X_OK) == 0) {
784 if (cmd == TYPECMD_SMALLV)
785 out1fmt("%s\n", argv[i]);
786 else
787 out1fmt("%s is %s\n", argv[i],
788 argv[i]);
789 } else {
790 if (cmd != TYPECMD_SMALLV)
791 outfmt(out2, "%s: %s\n",
792 argv[i], strerror(errno));
793 error |= 127;
794 }
795 }
796 break;
797 }
798 case CMDFUNCTION:
799 if (cmd == TYPECMD_SMALLV)
800 out1fmt("%s\n", argv[i]);
801 else
802 out1fmt("%s is a shell function\n", argv[i]);
803 break;
804
805 case CMDBUILTIN:
806 if (cmd == TYPECMD_SMALLV)
807 out1fmt("%s\n", argv[i]);
808 else if (entry.special)
809 out1fmt("%s is a special shell builtin\n",
810 argv[i]);
811 else
812 out1fmt("%s is a shell builtin\n", argv[i]);
813 break;
814
815 default:
816 if (cmd != TYPECMD_SMALLV)
817 outfmt(out2, "%s: not found\n", argv[i]);
818 error |= 127;
819 break;
820 }
821 }
822 return error;
823}
824
825/*
826 * Locate and print what a word is...
827 */
828
829int
830typecmd(int argc, char **argv)
831{
832 return typecmd_impl(argc, argv, TYPECMD_TYPE);
833}
|