xref: /netbsd-src/lib/libc/thread-stub/thread-stub.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: thread-stub.c,v 1.28 2016/10/31 18:10:11 kamil Exp $	*/
2 
3 /*-
4  * Copyright (c) 2003, 2009 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jason R. Thorpe.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #if defined(LIBC_SCCS) && !defined(lint)
34 __RCSID("$NetBSD: thread-stub.c,v 1.28 2016/10/31 18:10:11 kamil Exp $");
35 #endif /* LIBC_SCCS and not lint */
36 
37 /*
38  * Stubs for thread operations, for use when threads are not used by
39  * the application.  See "reentrant.h" for details.
40  */
41 
42 #ifdef _REENTRANT
43 
44 #define	__LIBC_THREAD_STUBS
45 
46 #define pthread_join	__libc_pthread_join
47 #define pthread_detach	__libc_pthread_detach
48 #include "namespace.h"
49 #include "reentrant.h"
50 
51 #include <errno.h>
52 #include <signal.h>
53 #include <stdlib.h>
54 #include <unistd.h>
55 
56 extern int __isthreaded;
57 
58 #define	DIE()	(void)raise(SIGABRT)
59 
60 #define	CHECK_NOT_THREADED_ALWAYS()	\
61 do {					\
62 	if (__isthreaded)		\
63 		DIE();			\
64 } while (/*CONSTCOND*/0)
65 
66 #if 1
67 #define	CHECK_NOT_THREADED()	CHECK_NOT_THREADED_ALWAYS()
68 #else
69 #define	CHECK_NOT_THREADED()	/* nothing */
70 #endif
71 
72 __weak_alias(pthread_join, __libc_pthread_join)
73 __weak_alias(pthread_detach, __libc_pthread_detach)
74 
75 int
76 pthread_join(pthread_t thread, void **valptr)
77 {
78 
79 	if (thread == pthread_self())
80 		return EDEADLK;
81 	return ESRCH;
82 }
83 
84 int
85 pthread_detach(pthread_t thread)
86 {
87 
88 	if (thread == pthread_self())
89 		return 0;
90 	return ESRCH;
91 }
92 
93 /* mutexes */
94 
95 int __libc_mutex_catchall_stub(mutex_t *);
96 
97 __weak_alias(__libc_mutex_init,__libc_mutex_init_stub)
98 __weak_alias(__libc_mutex_lock,__libc_mutex_catchall_stub)
99 __weak_alias(__libc_mutex_trylock,__libc_mutex_catchall_stub)
100 __weak_alias(__libc_mutex_unlock,__libc_mutex_catchall_stub)
101 __weak_alias(__libc_mutex_destroy,__libc_mutex_catchall_stub)
102 
103 __strong_alias(__libc_mutex_lock_stub,__libc_mutex_catchall_stub)
104 __strong_alias(__libc_mutex_trylock_stub,__libc_mutex_catchall_stub)
105 __strong_alias(__libc_mutex_unlock_stub,__libc_mutex_catchall_stub)
106 __strong_alias(__libc_mutex_destroy_stub,__libc_mutex_catchall_stub)
107 
108 int __libc_mutexattr_catchall_stub(mutexattr_t *);
109 
110 __weak_alias(__libc_mutexattr_init,__libc_mutexattr_catchall_stub)
111 __weak_alias(__libc_mutexattr_destroy,__libc_mutexattr_catchall_stub)
112 __weak_alias(__libc_mutexattr_settype,__libc_mutexattr_settype_stub)
113 
114 __strong_alias(__libc_mutexattr_init_stub,__libc_mutexattr_catchall_stub)
115 __strong_alias(__libc_mutexattr_destroy_stub,__libc_mutexattr_catchall_stub)
116 
117 int
118 __libc_mutex_init_stub(mutex_t *m, const mutexattr_t *a)
119 {
120 	/* LINTED deliberate lack of effect */
121 	(void)m;
122 	/* LINTED deliberate lack of effect */
123 	(void)a;
124 
125 	CHECK_NOT_THREADED();
126 
127 	return (0);
128 }
129 
130 int
131 __libc_mutex_catchall_stub(mutex_t *m)
132 {
133 	/* LINTED deliberate lack of effect */
134 	(void)m;
135 
136 	CHECK_NOT_THREADED();
137 
138 	return (0);
139 }
140 
141 int
142 __libc_mutexattr_settype_stub(mutexattr_t *ma, int type)
143 {
144 	/* LINTED deliberate lack of effect */
145 	(void)ma;
146 	/* LINTED deliberate lack of effect */
147 	(void)type;
148 
149 	CHECK_NOT_THREADED();
150 
151 	return (0);
152 }
153 
154 int
155 __libc_mutexattr_catchall_stub(mutexattr_t *ma)
156 {
157 	/* LINTED deliberate lack of effect */
158 	(void)ma;
159 
160 	CHECK_NOT_THREADED();
161 
162 	return (0);
163 }
164 
165 /* condition variables */
166 
167 int __libc_cond_catchall_stub(cond_t *);
168 
169 __weak_alias(__libc_cond_init,__libc_cond_init_stub)
170 __weak_alias(__libc_cond_signal,__libc_cond_catchall_stub)
171 __weak_alias(__libc_cond_broadcast,__libc_cond_catchall_stub)
172 __weak_alias(__libc_cond_wait,__libc_cond_catchall_stub)
173 __weak_alias(__libc_cond_timedwait,__libc_cond_timedwait_stub)
174 __weak_alias(__libc_cond_destroy,__libc_cond_catchall_stub)
175 
176 __strong_alias(__libc_cond_signal_stub,__libc_cond_catchall_stub)
177 __strong_alias(__libc_cond_broadcast_stub,__libc_cond_catchall_stub)
178 __strong_alias(__libc_cond_destroy_stub,__libc_cond_catchall_stub)
179 
180 int
181 __libc_cond_init_stub(cond_t *c, const condattr_t *a)
182 {
183 	/* LINTED deliberate lack of effect */
184 	(void)c;
185 	/* LINTED deliberate lack of effect */
186 	(void)a;
187 
188 	CHECK_NOT_THREADED();
189 
190 	return (0);
191 }
192 
193 int
194 __libc_cond_wait_stub(cond_t *c, mutex_t *m)
195 {
196 	/* LINTED deliberate lack of effect */
197 	(void)c;
198 	/* LINTED deliberate lack of effect */
199 	(void)m;
200 
201 	CHECK_NOT_THREADED();
202 
203 	return (0);
204 }
205 
206 int
207 __libc_cond_timedwait_stub(cond_t *c, mutex_t *m, const struct timespec *t)
208 {
209 	/* LINTED deliberate lack of effect */
210 	(void)c;
211 	/* LINTED deliberate lack of effect */
212 	(void)m;
213 	/* LINTED deliberate lack of effect */
214 	(void)t;
215 
216 	CHECK_NOT_THREADED();
217 
218 	return (0);
219 }
220 
221 int
222 __libc_cond_catchall_stub(cond_t *c)
223 {
224 	/* LINTED deliberate lack of effect */
225 	(void)c;
226 
227 	CHECK_NOT_THREADED();
228 
229 	return (0);
230 }
231 
232 
233 /* read-write locks */
234 
235 int __libc_rwlock_catchall_stub(rwlock_t *);
236 
237 __weak_alias(__libc_rwlock_init,__libc_rwlock_init_stub)
238 __weak_alias(__libc_rwlock_rdlock,__libc_rwlock_catchall_stub)
239 __weak_alias(__libc_rwlock_wrlock,__libc_rwlock_catchall_stub)
240 __weak_alias(__libc_rwlock_tryrdlock,__libc_rwlock_catchall_stub)
241 __weak_alias(__libc_rwlock_trywrlock,__libc_rwlock_catchall_stub)
242 __weak_alias(__libc_rwlock_unlock,__libc_rwlock_catchall_stub)
243 __weak_alias(__libc_rwlock_destroy,__libc_rwlock_catchall_stub)
244 
245 __strong_alias(__libc_rwlock_rdlock_stub,__libc_rwlock_catchall_stub)
246 __strong_alias(__libc_rwlock_wrlock_stub,__libc_rwlock_catchall_stub)
247 __strong_alias(__libc_rwlock_tryrdlock_stub,__libc_rwlock_catchall_stub)
248 __strong_alias(__libc_rwlock_trywrlock_stub,__libc_rwlock_catchall_stub)
249 __strong_alias(__libc_rwlock_unlock_stub,__libc_rwlock_catchall_stub)
250 __strong_alias(__libc_rwlock_destroy_stub,__libc_rwlock_catchall_stub)
251 
252 
253 int
254 __libc_rwlock_init_stub(rwlock_t *l, const rwlockattr_t *a)
255 {
256 	/* LINTED deliberate lack of effect */
257 	(void)l;
258 	/* LINTED deliberate lack of effect */
259 	(void)a;
260 
261 	CHECK_NOT_THREADED();
262 
263 	return (0);
264 }
265 
266 int
267 __libc_rwlock_catchall_stub(rwlock_t *l)
268 {
269 	/* LINTED deliberate lack of effect */
270 	(void)l;
271 
272 	CHECK_NOT_THREADED();
273 
274 	return (0);
275 }
276 
277 
278 /*
279  * thread-specific data; we need to actually provide a simple TSD
280  * implementation, since some thread-safe libraries want to use it.
281  */
282 
283 #define	TSD_KEYS_MAX	64
284 
285 static struct {
286 	void *tsd_val;
287 	void (*tsd_dtor)(void *);
288 	int tsd_inuse;
289 } __libc_tsd[TSD_KEYS_MAX];
290 static int __libc_tsd_nextkey;
291 
292 __weak_alias(__libc_thr_keycreate,__libc_thr_keycreate_stub)
293 __weak_alias(__libc_thr_setspecific,__libc_thr_setspecific_stub)
294 __weak_alias(__libc_thr_getspecific,__libc_thr_getspecific_stub)
295 __weak_alias(__libc_thr_keydelete,__libc_thr_keydelete_stub)
296 
297 int
298 __libc_thr_keycreate_stub(thread_key_t *k, void (*d)(void *))
299 {
300 	int i;
301 
302 	for (i = __libc_tsd_nextkey; i < TSD_KEYS_MAX; i++) {
303 		if (__libc_tsd[i].tsd_inuse == 0)
304 			goto out;
305 	}
306 
307 	for (i = 0; i < __libc_tsd_nextkey; i++) {
308 		if (__libc_tsd[i].tsd_inuse == 0)
309 			goto out;
310 	}
311 
312 	return (EAGAIN);
313 
314  out:
315 	/*
316 	 * XXX We don't actually do anything with the destructor.  We
317 	 * XXX probably should.
318 	 */
319 	__libc_tsd[i].tsd_inuse = 1;
320 	__libc_tsd_nextkey = (i + i) % TSD_KEYS_MAX;
321 	__libc_tsd[i].tsd_dtor = d;
322 	*k = i;
323 
324 	return (0);
325 }
326 
327 int
328 __libc_thr_setspecific_stub(thread_key_t k, const void *v)
329 {
330 
331 	__libc_tsd[k].tsd_val = __UNCONST(v);
332 
333 	return (0);
334 }
335 
336 void *
337 __libc_thr_getspecific_stub(thread_key_t k)
338 {
339 
340 	return (__libc_tsd[k].tsd_val);
341 }
342 
343 int
344 __libc_thr_keydelete_stub(thread_key_t k)
345 {
346 
347 	/*
348 	 * XXX Do not recycle key; see big comment in libpthread.
349 	 */
350 
351 	__libc_tsd[k].tsd_dtor = NULL;
352 
353 	return (0);
354 }
355 
356 
357 /* misc. */
358 
359 __weak_alias(__libc_thr_once,__libc_thr_once_stub)
360 __weak_alias(__libc_thr_sigsetmask,__libc_thr_sigsetmask_stub)
361 __weak_alias(__libc_thr_self,__libc_thr_self_stub)
362 __weak_alias(__libc_thr_yield,__libc_thr_yield_stub)
363 __weak_alias(__libc_thr_create,__libc_thr_create_stub)
364 __weak_alias(__libc_thr_exit,__libc_thr_exit_stub)
365 __weak_alias(__libc_thr_setcancelstate,__libc_thr_setcancelstate_stub)
366 __weak_alias(__libc_thr_equal,__libc_thr_equal_stub)
367 __weak_alias(__libc_thr_curcpu,__libc_thr_curcpu_stub)
368 
369 
370 int
371 __libc_thr_once_stub(once_t *o, void (*r)(void))
372 {
373 
374 	/* XXX Knowledge of libpthread types. */
375 
376 	if (o->pto_done == 0) {
377 		(*r)();
378 		o->pto_done = 1;
379 	}
380 
381 	return (0);
382 }
383 
384 int
385 __libc_thr_sigsetmask_stub(int h, const sigset_t *s, sigset_t *o)
386 {
387 
388 	CHECK_NOT_THREADED();
389 
390 	return sigprocmask(h, s, o);
391 }
392 
393 thr_t
394 __libc_thr_self_stub(void)
395 {
396 
397 	return ((thr_t) -1);
398 }
399 
400 int
401 __libc_thr_yield_stub(void)
402 {
403 
404 	/* Nothing to do. */
405 	return (0);
406 }
407 
408 int
409 __libc_thr_create_stub(thr_t *tp, const thrattr_t *ta,
410     void *(*f)(void *), void *a)
411 {
412 	/* LINTED deliberate lack of effect */
413 	(void)tp;
414 	/* LINTED deliberate lack of effect */
415 	(void)ta;
416 	/* LINTED deliberate lack of effect */
417 	(void)f;
418 	/* LINTED deliberate lack of effect */
419 	(void)a;
420 
421 	DIE();
422 
423 	return (EOPNOTSUPP);
424 }
425 
426 __dead void
427 __libc_thr_exit_stub(void *v)
428 {
429 	/* LINTED deliberate lack of effect */
430 	(void)v;
431 	exit(0);
432 }
433 
434 int
435 __libc_thr_setcancelstate_stub(int new, int *old)
436 {
437 	/* LINTED deliberate lack of effect */
438 	(void)new;
439 
440 	/* LINTED deliberate lack of effect */
441 	(void)old;
442 
443 	CHECK_NOT_THREADED();
444 
445 	return (0);
446 }
447 
448 int
449 __libc_thr_equal_stub(pthread_t t1, pthread_t t2)
450 {
451 
452 	/* assert that t1=t2=pthread_self() */
453 	return (t1 == t2);
454 }
455 
456 unsigned int
457 __libc_thr_curcpu_stub(void)
458 {
459 
460 	return (0);
461 }
462 
463 #endif /* _REENTRANT */
464