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[perl5.git] / thread.h
1 /*    thread.h
2  *
3  *    Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
4  *    by Larry Wall and others
5  *
6  *    You may distribute under the terms of either the GNU General Public
7  *    License or the Artistic License, as specified in the README file.
8  *
9  */
10
11 #if defined(USE_ITHREADS)
12
13 #if defined(VMS)
14 #include <builtins.h>
15 #endif
16
17 #ifdef WIN32
18 #  include <win32thread.h>
19 #else
20 #ifdef NETWARE
21 #  include <nw5thread.h>
22 #else
23 #  ifdef OLD_PTHREADS_API /* Here be dragons. */
24 #    define DETACH(t) \
25     STMT_START {                                                \
26         int _eC_;                                               \
27         if ((_eC_ = pthread_detach(&(t)->self))) {              \
28             MUTEX_UNLOCK(&(t)->mutex);                          \
29             Perl_croak_nocontext("panic: DETACH (%d) [%s:%d]",  \
30                                  _eC_, __FILE__, __LINE__);     \
31         }                                                       \
32     } STMT_END
33
34 #    define PERL_GET_CONTEXT    Perl_get_context()
35 #    define PERL_SET_CONTEXT(t) Perl_set_context((void*)t)
36
37 #    define PTHREAD_GETSPECIFIC_INT
38 #    ifdef DJGPP
39 #      define pthread_addr_t any_t
40 #      define NEED_PTHREAD_INIT
41 #      define PTHREAD_CREATE_JOINABLE (1)
42 #    endif
43 #    ifdef __OPEN_VM
44 #      define pthread_addr_t void *
45 #    endif
46 #    ifdef OEMVS
47 #      define pthread_addr_t void *
48 #      define pthread_create(t,a,s,d)        pthread_create(t,&(a),s,d)
49 #      define pthread_keycreate              pthread_key_create
50 #    endif
51 #    ifdef VMS
52 #      define pthread_attr_init(a) pthread_attr_create(a)
53 #      define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_setdetach_np(a,s)
54 #      define PTHREAD_CREATE(t,a,s,d) pthread_create(t,a,s,d)
55 #      define pthread_key_create(k,d) pthread_keycreate(k,(pthread_destructor_t)(d))
56 #      define pthread_mutexattr_init(a) pthread_mutexattr_create(a)
57 #      define pthread_mutexattr_settype(a,t) pthread_mutexattr_setkind_np(a,t)
58 #    endif
59 #    if defined(__hpux) && defined(__ux_version) && __ux_version <= 1020
60 #      define pthread_attr_init(a) pthread_attr_create(a)
61        /* XXX pthread_setdetach_np() missing in DCE threads on HP-UX 10.20 */
62 #      define PTHREAD_ATTR_SETDETACHSTATE(a,s)  (0)
63 #      define PTHREAD_CREATE(t,a,s,d) pthread_create(t,a,s,d)
64 #      define pthread_key_create(k,d) pthread_keycreate(k,(pthread_destructor_t)(d))
65 #      define pthread_mutexattr_init(a) pthread_mutexattr_create(a)
66 #      define pthread_mutexattr_settype(a,t) pthread_mutexattr_setkind_np(a,t)
67 #    endif
68 #    if defined(DJGPP) || defined(__OPEN_VM) || defined(OEMVS)
69 #      define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_attr_setdetachstate(a,&(s))
70 #      define YIELD pthread_yield(NULL)
71 #    endif
72 #  endif
73 #  if !defined(__hpux) || !defined(__ux_version) || __ux_version > 1020
74 #    define pthread_mutexattr_default NULL
75 #    define pthread_condattr_default  NULL
76 #  endif
77 #endif  /* NETWARE */
78 #endif
79
80 #ifndef PTHREAD_CREATE
81 /* You are not supposed to pass NULL as the 2nd arg of PTHREAD_CREATE(). */
82 #  define PTHREAD_CREATE(t,a,s,d) pthread_create(t,&(a),s,d)
83 #endif
84
85 #ifndef PTHREAD_ATTR_SETDETACHSTATE
86 #  define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_attr_setdetachstate(a,s)
87 #endif
88
89 #ifndef PTHREAD_CREATE_JOINABLE
90 #  ifdef OLD_PTHREAD_CREATE_JOINABLE
91 #    define PTHREAD_CREATE_JOINABLE OLD_PTHREAD_CREATE_JOINABLE
92 #  else
93 #    define PTHREAD_CREATE_JOINABLE 0 /* Panic?  No, guess. */
94 #  endif
95 #endif
96
97 #ifdef DGUX
98 #  define THREAD_CREATE_NEEDS_STACK (32*1024)
99 #endif
100
101 #ifdef __VMS
102   /* Default is 1024 on VAX, 8192 otherwise */
103 #  define THREAD_CREATE_NEEDS_STACK (32*1024)
104 #endif
105
106 #ifdef I_MACH_CTHREADS
107
108 /* cthreads interface */
109
110 /* #include <mach/cthreads.h> is in perl.h #ifdef I_MACH_CTHREADS */
111
112 #define MUTEX_INIT(m) \
113     STMT_START {                                                \
114         *m = mutex_alloc();                                     \
115         if (*m) {                                               \
116             mutex_init(*m);                                     \
117         } else {                                                \
118             Perl_croak_nocontext("panic: MUTEX_INIT [%s:%d]",   \
119                                  __FILE__, __LINE__);           \
120         }                                                       \
121     } STMT_END
122
123 #define MUTEX_LOCK(m)                   mutex_lock(*m)
124 #define MUTEX_UNLOCK(m)                 mutex_unlock(*m)
125 #define MUTEX_DESTROY(m) \
126     STMT_START {                                                \
127         mutex_free(*m);                                         \
128         *m = 0;                                                 \
129     } STMT_END
130
131 #define COND_INIT(c) \
132     STMT_START {                                                \
133         *c = condition_alloc();                                 \
134         if (*c) {                                               \
135             condition_init(*c);                                 \
136         }                                                       \
137         else {                                                  \
138             Perl_croak_nocontext("panic: COND_INIT [%s:%d]",    \
139                                  __FILE__, __LINE__);           \
140         }                                                       \
141     } STMT_END
142
143 #define COND_SIGNAL(c)          condition_signal(*c)
144 #define COND_BROADCAST(c)       condition_broadcast(*c)
145 #define COND_WAIT(c, m)         condition_wait(*c, *m)
146 #define COND_DESTROY(c) \
147     STMT_START {                                                \
148         condition_free(*c);                                     \
149         *c = 0;                                                 \
150     } STMT_END
151
152 #define THREAD_CREATE(thr, f)   (thr->self = cthread_fork(f, thr), 0)
153 #define THREAD_POST_CREATE(thr)
154
155 #define THREAD_RET_TYPE         any_t
156 #define THREAD_RET_CAST(x)      ((any_t) x)
157
158 #define DETACH(t)               cthread_detach(t->self)
159 #define JOIN(t, avp)            (*(avp) = (AV *)cthread_join(t->self))
160
161 #define PERL_SET_CONTEXT(t)     cthread_set_data(cthread_self(), t)
162 #define PERL_GET_CONTEXT        cthread_data(cthread_self())
163
164 #define INIT_THREADS            cthread_init()
165 #define YIELD                   cthread_yield()
166 #define ALLOC_THREAD_KEY        NOOP
167 #define FREE_THREAD_KEY         NOOP
168 #define SET_THREAD_SELF(thr)    (thr->self = cthread_self())
169
170 #endif /* I_MACH_CTHREADS */
171
172 #ifndef YIELD
173 #  ifdef SCHED_YIELD
174 #    define YIELD SCHED_YIELD
175 #  else
176 #    ifdef HAS_SCHED_YIELD
177 #      define YIELD sched_yield()
178 #    else
179 #      ifdef HAS_PTHREAD_YIELD
180     /* pthread_yield(NULL) platforms are expected
181      * to have #defined YIELD for themselves. */
182 #        define YIELD pthread_yield()
183 #      endif
184 #    endif
185 #  endif
186 #endif
187
188 #ifdef __hpux
189 #  define MUTEX_INIT_NEEDS_MUTEX_ZEROED
190 #endif
191
192 #ifndef MUTEX_INIT
193
194 #  ifdef MUTEX_INIT_NEEDS_MUTEX_ZEROED
195     /* Temporary workaround, true bug is deeper. --jhi 1999-02-25 */
196 #    define MUTEX_INIT(m) \
197     STMT_START {                                                \
198         int _eC_;                                               \
199         Zero((m), 1, perl_mutex);                               \
200         if ((_eC_ = pthread_mutex_init((m), pthread_mutexattr_default)))        \
201             Perl_croak_nocontext("panic: MUTEX_INIT (%d) [%s:%d]",      \
202                                  _eC_, __FILE__, __LINE__);     \
203     } STMT_END
204 #  else
205 #    define MUTEX_INIT(m) \
206     STMT_START {                                                \
207         int _eC_;                                               \
208         if ((_eC_ = pthread_mutex_init((m), pthread_mutexattr_default)))        \
209             Perl_croak_nocontext("panic: MUTEX_INIT (%d) [%s:%d]",      \
210                                  _eC_, __FILE__, __LINE__);     \
211     } STMT_END
212 #  endif
213
214 #  define MUTEX_LOCK(m) \
215     STMT_START {                                                \
216         int _eC_;                                               \
217         if ((_eC_ = pthread_mutex_lock((m))))                   \
218             Perl_croak_nocontext("panic: MUTEX_LOCK (%d) [%s:%d]",      \
219                                  _eC_, __FILE__, __LINE__);     \
220     } STMT_END
221
222 #  define MUTEX_UNLOCK(m) \
223     STMT_START {                                                \
224         int _eC_;                                               \
225         if ((_eC_ = pthread_mutex_unlock((m))))                 \
226             Perl_croak_nocontext("panic: MUTEX_UNLOCK (%d) [%s:%d]",    \
227                                  _eC_, __FILE__, __LINE__);     \
228     } STMT_END
229
230 #  define MUTEX_DESTROY(m) \
231     STMT_START {                                                \
232         int _eC_;                                               \
233         if ((_eC_ = pthread_mutex_destroy((m))))                \
234             Perl_croak_nocontext("panic: MUTEX_DESTROY (%d) [%s:%d]",   \
235                                  _eC_, __FILE__, __LINE__);     \
236     } STMT_END
237 #endif /* MUTEX_INIT */
238
239 #ifndef COND_INIT
240 #  define COND_INIT(c) \
241     STMT_START {                                                \
242         int _eC_;                                               \
243         if ((_eC_ = pthread_cond_init((c), pthread_condattr_default)))  \
244             Perl_croak_nocontext("panic: COND_INIT (%d) [%s:%d]",       \
245                                  _eC_, __FILE__, __LINE__);     \
246     } STMT_END
247
248 #  define COND_SIGNAL(c) \
249     STMT_START {                                                \
250         int _eC_;                                               \
251         if ((_eC_ = pthread_cond_signal((c))))                  \
252             Perl_croak_nocontext("panic: COND_SIGNAL (%d) [%s:%d]",     \
253                                  _eC_, __FILE__, __LINE__);     \
254     } STMT_END
255
256 #  define COND_BROADCAST(c) \
257     STMT_START {                                                \
258         int _eC_;                                               \
259         if ((_eC_ = pthread_cond_broadcast((c))))               \
260             Perl_croak_nocontext("panic: COND_BROADCAST (%d) [%s:%d]",  \
261                                  _eC_, __FILE__, __LINE__);     \
262     } STMT_END
263
264 #  define COND_WAIT(c, m) \
265     STMT_START {                                                \
266         int _eC_;                                               \
267         if ((_eC_ = pthread_cond_wait((c), (m))))               \
268             Perl_croak_nocontext("panic: COND_WAIT (%d) [%s:%d]",       \
269                                  _eC_, __FILE__, __LINE__);     \
270     } STMT_END
271
272 #  define COND_DESTROY(c) \
273     STMT_START {                                                \
274         int _eC_;                                               \
275         if ((_eC_ = pthread_cond_destroy((c))))                 \
276             Perl_croak_nocontext("panic: COND_DESTROY (%d) [%s:%d]",    \
277                                  _eC_, __FILE__, __LINE__);     \
278     } STMT_END
279 #endif /* COND_INIT */
280
281 /* DETACH(t) must only be called while holding t->mutex */
282 #ifndef DETACH
283 #  define DETACH(t) \
284     STMT_START {                                                \
285         int _eC_;                                               \
286         if ((_eC_ = pthread_detach((t)->self))) {               \
287             MUTEX_UNLOCK(&(t)->mutex);                          \
288             Perl_croak_nocontext("panic: DETACH (%d) [%s:%d]",  \
289                                  _eC_, __FILE__, __LINE__);     \
290         }                                                       \
291     } STMT_END
292 #endif /* DETACH */
293
294 #ifndef JOIN
295 #  define JOIN(t, avp) \
296     STMT_START {                                                \
297         int _eC_;                                               \
298         if ((_eC_ = pthread_join((t)->self, (void**)(avp))))    \
299             Perl_croak_nocontext("panic: pthread_join (%d) [%s:%d]",    \
300                                  _eC_, __FILE__, __LINE__);     \
301     } STMT_END
302 #endif /* JOIN */
303
304 /* Use an unchecked fetch of thread-specific data instead of a checked one.
305  * It would fail if the key were bogus, but if the key were bogus then
306  * Really Bad Things would be happening anyway. --dan */
307 #if (defined(__ALPHA) && (__VMS_VER >= 70000000)) || \
308     (defined(__alpha) && defined(__osf__) && !defined(__GNUC__)) /* Available only on >= 4.0 */
309 #  define HAS_PTHREAD_UNCHECKED_GETSPECIFIC_NP /* Configure test needed */
310 #endif
311
312 #ifdef HAS_PTHREAD_UNCHECKED_GETSPECIFIC_NP
313 #  define PTHREAD_GETSPECIFIC(key) pthread_unchecked_getspecific_np(key)
314 #else
315 #    define PTHREAD_GETSPECIFIC(key) pthread_getspecific(key)
316 #endif
317
318 #ifndef PERL_GET_CONTEXT
319 #  define PERL_GET_CONTEXT      PTHREAD_GETSPECIFIC(PL_thr_key)
320 #endif
321
322 #ifndef PERL_SET_CONTEXT
323 #  define PERL_SET_CONTEXT(t) \
324     STMT_START {                                                \
325         int _eC_;                                               \
326         if ((_eC_ = pthread_setspecific(PL_thr_key, (void *)(t))))      \
327             Perl_croak_nocontext("panic: pthread_setspecific (%d) [%s:%d]",     \
328                                  _eC_, __FILE__, __LINE__);     \
329     } STMT_END
330 #endif /* PERL_SET_CONTEXT */
331
332 #ifndef INIT_THREADS
333 #  ifdef NEED_PTHREAD_INIT
334 #    define INIT_THREADS pthread_init()
335 #  endif
336 #endif
337
338 #ifndef ALLOC_THREAD_KEY
339 #  define ALLOC_THREAD_KEY \
340     STMT_START {                                                \
341         if (pthread_key_create(&PL_thr_key, 0)) {               \
342             write(2, STR_WITH_LEN("panic: pthread_key_create failed\n")); \
343             exit(1);                                            \
344         }                                                       \
345     } STMT_END
346 #endif
347
348 #ifndef FREE_THREAD_KEY
349 #  define FREE_THREAD_KEY \
350     STMT_START {                                                \
351         pthread_key_delete(PL_thr_key);                         \
352     } STMT_END
353 #endif
354
355 #ifndef PTHREAD_ATFORK
356 #  ifdef HAS_PTHREAD_ATFORK
357 #    define PTHREAD_ATFORK(prepare,parent,child)                \
358         pthread_atfork(prepare,parent,child)
359 #  else
360 #    define PTHREAD_ATFORK(prepare,parent,child)                \
361         NOOP
362 #  endif
363 #endif
364
365 #ifndef THREAD_RET_TYPE
366 #  define THREAD_RET_TYPE       void *
367 #  define THREAD_RET_CAST(p)    ((void *)(p))
368 #endif /* THREAD_RET */
369
370 #  define LOCK_DOLLARZERO_MUTEX         MUTEX_LOCK(&PL_dollarzero_mutex)
371 #  define UNLOCK_DOLLARZERO_MUTEX       MUTEX_UNLOCK(&PL_dollarzero_mutex)
372
373 #endif /* USE_ITHREADS */
374
375 #ifndef MUTEX_LOCK
376 #  define MUTEX_LOCK(m)
377 #endif
378
379 #ifndef MUTEX_UNLOCK
380 #  define MUTEX_UNLOCK(m)
381 #endif
382
383 #ifndef MUTEX_INIT
384 #  define MUTEX_INIT(m)
385 #endif
386
387 #ifndef MUTEX_DESTROY
388 #  define MUTEX_DESTROY(m)
389 #endif
390
391 #ifndef COND_INIT
392 #  define COND_INIT(c)
393 #endif
394
395 #ifndef COND_SIGNAL
396 #  define COND_SIGNAL(c)
397 #endif
398
399 #ifndef COND_BROADCAST
400 #  define COND_BROADCAST(c)
401 #endif
402
403 #ifndef COND_WAIT
404 #  define COND_WAIT(c, m)
405 #endif
406
407 #ifndef COND_DESTROY
408 #  define COND_DESTROY(c)
409 #endif
410
411 #ifndef LOCK_SV_MUTEX
412 #  define LOCK_SV_MUTEX
413 #endif
414
415 #ifndef UNLOCK_SV_MUTEX
416 #  define UNLOCK_SV_MUTEX
417 #endif
418
419 #ifndef LOCK_STRTAB_MUTEX
420 #  define LOCK_STRTAB_MUTEX
421 #endif
422
423 #ifndef UNLOCK_STRTAB_MUTEX
424 #  define UNLOCK_STRTAB_MUTEX
425 #endif
426
427 #ifndef LOCK_CRED_MUTEX
428 #  define LOCK_CRED_MUTEX
429 #endif
430
431 #ifndef UNLOCK_CRED_MUTEX
432 #  define UNLOCK_CRED_MUTEX
433 #endif
434
435 #ifndef LOCK_FDPID_MUTEX
436 #  define LOCK_FDPID_MUTEX
437 #endif
438
439 #ifndef UNLOCK_FDPID_MUTEX
440 #  define UNLOCK_FDPID_MUTEX
441 #endif
442
443 #ifndef LOCK_SV_LOCK_MUTEX
444 #  define LOCK_SV_LOCK_MUTEX
445 #endif
446
447 #ifndef UNLOCK_SV_LOCK_MUTEX
448 #  define UNLOCK_SV_LOCK_MUTEX
449 #endif
450
451 #ifndef LOCK_DOLLARZERO_MUTEX
452 #  define LOCK_DOLLARZERO_MUTEX
453 #endif
454
455 #ifndef UNLOCK_DOLLARZERO_MUTEX
456 #  define UNLOCK_DOLLARZERO_MUTEX
457 #endif
458
459 /* THR, SET_THR, and dTHR are there for compatibility with old versions */
460 #ifndef THR
461 #  define THR           PERL_GET_THX
462 #endif
463
464 #ifndef SET_THR
465 #  define SET_THR(t)    PERL_SET_THX(t)
466 #endif
467
468 #ifndef dTHR
469 #  define dTHR dNOOP
470 #endif
471
472 #ifndef INIT_THREADS
473 #  define INIT_THREADS NOOP
474 #endif
475
476 /*
477  * Local variables:
478  * c-indentation-style: bsd
479  * c-basic-offset: 4
480  * indent-tabs-mode: t
481  * End:
482  *
483  * ex: set ts=8 sts=4 sw=4 noet:
484  */