This is a live mirror of the Perl 5 development currently hosted at https://github.com/perl/perl5
VMS.C tweak for occasional system() error
[perl5.git] / thread.h
1 #ifdef USE_THREADS
2
3 #ifdef WIN32
4 #  include <win32thread.h>
5 #else
6 #  ifdef OLD_PTHREADS_API /* Here be dragons. */
7 #    define DETACH(t)                           \
8     STMT_START {                                \
9         if (pthread_detach(&(t)->self)) {       \
10             MUTEX_UNLOCK(&(t)->mutex);          \
11             croak("panic: DETACH");             \
12         }                                       \
13     } STMT_END
14 #    define THR getTHR()
15 struct perl_thread *getTHR _((void));
16 #    define PTHREAD_GETSPECIFIC_INT
17 #    ifdef DJGPP
18 #      define pthread_addr_t any_t
19 #      define NEED_PTHREAD_INIT
20 #      define PTHREAD_CREATE_JOINABLE (1)
21 #    endif
22 #    ifdef __OPEN_VM
23 #      define pthread_addr_t void *
24 #    endif
25 #    ifdef VMS
26 #      define pthread_attr_init(a) pthread_attr_create(a)
27 #      define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_setdetach_np(a,s)
28 #      define PTHREAD_CREATE(t,a,s,d) pthread_create(t,a,s,d)
29 #      define pthread_key_create(k,d) pthread_keycreate(k,(pthread_destructor_t)(d))
30 #      define pthread_mutexattr_init(a) pthread_mutexattr_create(a)
31 #      define pthread_mutexattr_settype(a,t) pthread_mutexattr_setkind_np(a,t)
32 #    endif
33 #    if defined(DJGPP) || defined(__OPEN_VM)
34 #      define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_attr_setdetachstate(a,&(s))
35 #      define YIELD pthread_yield(NULL)
36 #    endif
37 #  endif
38 #  ifndef VMS
39 #    define pthread_mutexattr_default NULL
40 #    define pthread_condattr_default  NULL
41 #  endif
42 #endif
43
44 #ifndef PTHREAD_CREATE
45 /* You are not supposed to pass NULL as the 2nd arg of PTHREAD_CREATE(). */
46 #  define PTHREAD_CREATE(t,a,s,d) pthread_create(t,&(a),s,d)
47 #endif
48
49 #ifndef PTHREAD_ATTR_SETDETACHSTATE
50 #  define PTHREAD_ATTR_SETDETACHSTATE(a,s) pthread_attr_setdetachstate(a,s)
51 #endif
52
53 #ifndef PTHREAD_CREATE_JOINABLE
54 #  ifdef OLD_PTHREAD_CREATE_JOINABLE
55 #    define PTHREAD_CREATE_JOINABLE OLD_PTHREAD_CREATE_JOINABLE
56 #  else
57 #    define PTHREAD_CREATE_JOINABLE 0 /* Panic?  No, guess. */
58 #  endif
59 #endif
60
61 #ifdef I_MACH_CTHREADS
62
63 /* cthreads interface */
64
65 /* #include <mach/cthreads.h> is in perl.h #ifdef I_MACH_CTHREADS */
66
67 #define MUTEX_INIT(m)                                   \
68         STMT_START {                                    \
69                 *m = mutex_alloc();                     \
70                 if (*m) {                               \
71                         mutex_init(*m);                 \
72                 } else {                                \
73                         croak("panic: MUTEX_INIT");     \
74                 }                                       \
75         } STMT_END
76
77 #define MUTEX_LOCK(m)           mutex_lock(*m)
78 #define MUTEX_UNLOCK(m)         mutex_unlock(*m)
79 #define MUTEX_DESTROY(m)                                \
80         STMT_START {                                    \
81                 mutex_free(*m);                         \
82                 *m = 0;                                 \
83         } STMT_END
84
85 #define COND_INIT(c)                                    \
86         STMT_START {                                    \
87                 *c = condition_alloc();                 \
88                 if (*c) {                               \
89                         condition_init(*c);             \
90                 } else {                                \
91                         croak("panic: COND_INIT");      \
92                 }                                       \
93         } STMT_END
94
95 #define COND_SIGNAL(c)          condition_signal(*c)
96 #define COND_BROADCAST(c)       condition_broadcast(*c)
97 #define COND_WAIT(c, m)         condition_wait(*c, *m)
98 #define COND_DESTROY(c)                         \
99         STMT_START {                            \
100                 condition_free(*c);             \
101                 *c = 0;                         \
102         } STMT_END
103
104 #define THREAD_CREATE(thr, f)   (thr->self = cthread_fork(f, thr), 0)
105 #define THREAD_POST_CREATE(thr)
106
107 #define THREAD_RET_TYPE         any_t
108 #define THREAD_RET_CAST(x)      ((any_t) x)
109
110 #define DETACH(t)               cthread_detach(t->self)
111 #define JOIN(t, avp)            (*(avp) = (AV *)cthread_join(t->self))
112
113 #define SET_THR(thr)            cthread_set_data(cthread_self(), thr)
114 #define THR                     cthread_data(cthread_self())
115
116 #define INIT_THREADS            cthread_init()
117 #define YIELD                   cthread_yield()
118 #define ALLOC_THREAD_KEY
119 #define SET_THREAD_SELF(thr)    (thr->self = cthread_self())
120
121 #endif /* I_MACH_CTHREADS */
122
123 #ifndef YIELD
124 #  ifdef SCHED_YIELD
125 #    define YIELD SCHED_YIELD
126 #  else
127 #    ifdef HAS_SCHED_YIELD
128 #      define YIELD sched_yield()
129 #    else
130 #      ifdef HAS_PTHREAD_YIELD
131     /* pthread_yield(NULL) platforms are expected
132      * to have #defined YIELD for themselves. */
133 #        define YIELD pthread_yield()
134 #      endif
135 #    endif
136 #  endif
137 #endif
138
139 #ifndef MUTEX_INIT
140 #define MUTEX_INIT(m)                                           \
141     STMT_START {                                                \
142         if (pthread_mutex_init((m), pthread_mutexattr_default)) \
143             croak("panic: MUTEX_INIT");                         \
144     } STMT_END
145 #define MUTEX_LOCK(m)                           \
146     STMT_START {                                \
147         if (pthread_mutex_lock((m)))            \
148             croak("panic: MUTEX_LOCK");         \
149     } STMT_END
150 #define MUTEX_UNLOCK(m)                         \
151     STMT_START {                                \
152         if (pthread_mutex_unlock((m)))          \
153             croak("panic: MUTEX_UNLOCK");       \
154     } STMT_END
155 #define MUTEX_DESTROY(m)                        \
156     STMT_START {                                \
157         if (pthread_mutex_destroy((m)))         \
158             croak("panic: MUTEX_DESTROY");      \
159     } STMT_END
160 #endif /* MUTEX_INIT */
161
162 #ifndef COND_INIT
163 #define COND_INIT(c)                                            \
164     STMT_START {                                                \
165         if (pthread_cond_init((c), pthread_condattr_default))   \
166             croak("panic: COND_INIT");                          \
167     } STMT_END
168 #define COND_SIGNAL(c)                          \
169     STMT_START {                                \
170         if (pthread_cond_signal((c)))           \
171             croak("panic: COND_SIGNAL");        \
172     } STMT_END
173 #define COND_BROADCAST(c)                       \
174     STMT_START {                                \
175         if (pthread_cond_broadcast((c)))        \
176             croak("panic: COND_BROADCAST");     \
177     } STMT_END
178 #define COND_WAIT(c, m)                         \
179     STMT_START {                                \
180         if (pthread_cond_wait((c), (m)))        \
181             croak("panic: COND_WAIT");          \
182     } STMT_END
183 #define COND_DESTROY(c)                         \
184     STMT_START {                                \
185         if (pthread_cond_destroy((c)))          \
186             croak("panic: COND_DESTROY");       \
187     } STMT_END
188 #endif /* COND_INIT */
189
190 /* DETACH(t) must only be called while holding t->mutex */
191 #ifndef DETACH
192 #define DETACH(t)                               \
193     STMT_START {                                \
194         if (pthread_detach((t)->self)) {        \
195             MUTEX_UNLOCK(&(t)->mutex);          \
196             croak("panic: DETACH");             \
197         }                                       \
198     } STMT_END
199 #endif /* DETACH */
200
201 #ifndef JOIN
202 #define JOIN(t, avp)                                    \
203     STMT_START {                                        \
204         if (pthread_join((t)->self, (void**)(avp)))     \
205             croak("panic: pthread_join");               \
206     } STMT_END
207 #endif /* JOIN */
208
209 #ifndef SET_THR
210 #define SET_THR(t)                                      \
211     STMT_START {                                        \
212         if (pthread_setspecific(PL_thr_key, (void *) (t)))      \
213             croak("panic: pthread_setspecific");        \
214     } STMT_END
215 #endif /* SET_THR */
216
217 #ifndef THR
218 #define THR ((struct perl_thread *) pthread_getspecific(PL_thr_key))
219 #endif
220
221 /*
222  * dTHR is performance-critical. Here, we only do the pthread_get_specific
223  * if there may be more than one thread in existence, otherwise we get thr
224  * from thrsv which is cached in the per-interpreter structure.
225  * Systems with very fast pthread_get_specific (which should be all systems
226  * but unfortunately isn't) may wish to simplify to "...*thr = THR".
227  *
228  * The use of PL_threadnum should be safe here.
229  */
230 #ifndef dTHR
231 #  define dTHR \
232     struct perl_thread *thr = PL_threadnum? THR : (struct perl_thread*)SvPVX(PL_thrsv)
233 #endif /* dTHR */
234
235 #ifndef INIT_THREADS
236 #  ifdef NEED_PTHREAD_INIT
237 #    define INIT_THREADS pthread_init()
238 #  else
239 #    define INIT_THREADS NOOP
240 #  endif
241 #endif
242
243 /* Accessor for per-thread SVs */
244 #define THREADSV(i) (thr->threadsvp[i])
245
246 /*
247  * LOCK_SV_MUTEX and UNLOCK_SV_MUTEX are performance-critical. Here, we
248  * try only locking them if there may be more than one thread in existence.
249  * Systems with very fast mutexes (and/or slow conditionals) may wish to
250  * remove the "if (threadnum) ..." test.
251  * XXX do NOT use C<if (PL_threadnum) ...> -- it sets up race conditions!
252  */
253 #define LOCK_SV_MUTEX                           \
254     STMT_START {                                \
255         MUTEX_LOCK(&PL_sv_mutex);               \
256     } STMT_END
257
258 #define UNLOCK_SV_MUTEX                         \
259     STMT_START {                                \
260         MUTEX_UNLOCK(&PL_sv_mutex);             \
261     } STMT_END
262
263 /* Likewise for strtab_mutex */
264 #define LOCK_STRTAB_MUTEX                       \
265     STMT_START {                                \
266         MUTEX_LOCK(&PL_strtab_mutex);           \
267     } STMT_END
268
269 #define UNLOCK_STRTAB_MUTEX                     \
270     STMT_START {                                \
271         MUTEX_UNLOCK(&PL_strtab_mutex);         \
272     } STMT_END
273
274 #ifndef THREAD_RET_TYPE
275 #  define THREAD_RET_TYPE       void *
276 #  define THREAD_RET_CAST(p)    ((void *)(p))
277 #endif /* THREAD_RET */
278
279
280 /* Values and macros for thr->flags */
281 #define THRf_STATE_MASK 7
282 #define THRf_R_JOINABLE 0
283 #define THRf_R_JOINED   1
284 #define THRf_R_DETACHED 2
285 #define THRf_ZOMBIE     3
286 #define THRf_DEAD       4
287
288 #define THRf_DID_DIE    8
289
290 /* ThrSTATE(t) and ThrSETSTATE(t) must only be called while holding t->mutex */
291 #define ThrSTATE(t) ((t)->flags & THRf_STATE_MASK)
292 #define ThrSETSTATE(t, s) STMT_START {          \
293         (t)->flags &= ~THRf_STATE_MASK;         \
294         (t)->flags |= (s);                      \
295         DEBUG_S(PerlIO_printf(PerlIO_stderr(),  \
296                               "thread %p set to state %d\n", (t), (s))); \
297     } STMT_END
298
299 typedef struct condpair {
300     perl_mutex  mutex;          /* Protects all other fields */
301     perl_cond   owner_cond;     /* For when owner changes at all */
302     perl_cond   cond;           /* For cond_signal and cond_broadcast */
303     Thread      owner;          /* Currently owning thread */
304 } condpair_t;
305
306 #define MgMUTEXP(mg) (&((condpair_t *)(mg->mg_ptr))->mutex)
307 #define MgOWNERCONDP(mg) (&((condpair_t *)(mg->mg_ptr))->owner_cond)
308 #define MgCONDP(mg) (&((condpair_t *)(mg->mg_ptr))->cond)
309 #define MgOWNER(mg) ((condpair_t *)(mg->mg_ptr))->owner
310
311 #else
312 /* USE_THREADS is not defined */
313 #define MUTEX_LOCK(m)
314 #define MUTEX_UNLOCK(m)
315 #define MUTEX_INIT(m)
316 #define MUTEX_DESTROY(m)
317 #define COND_INIT(c)
318 #define COND_SIGNAL(c)
319 #define COND_BROADCAST(c)
320 #define COND_WAIT(c, m)
321 #define COND_DESTROY(c)
322 #define LOCK_SV_MUTEX
323 #define UNLOCK_SV_MUTEX
324 #define LOCK_STRTAB_MUTEX
325 #define UNLOCK_STRTAB_MUTEX
326
327 #define THR
328 /* Rats: if dTHR is just blank then the subsequent ";" throws an error */
329 #ifdef WIN32
330 #define dTHR extern int Perl___notused
331 #else
332 #define dTHR extern int errno
333 #endif
334 #endif /* USE_THREADS */