History

add hg and python

cinap_lenrek committed 15 years ago

Commit 4bb9e221 parent 987265c3706 files · +1228772 −-233Browse files

Showing the changes to sys/src/cmd/python/Python/thread_pthread.h (1 of 3706 files). Show all

Unified · Split

sys/src/cmd/python/Python/thread_pthread.h+533−0
@@ -0,0 +1,533 @@
1+
2+/* Posix threads interface */
3+
4+#include <stdlib.h>
5+#include <string.h>
6+#if defined(__APPLE__) || defined(HAVE_PTHREAD_DESTRUCTOR)
7+#define destructor xxdestructor
8+#endif
9+#include <pthread.h>
10+#if defined(__APPLE__) || defined(HAVE_PTHREAD_DESTRUCTOR)
11+#undef destructor
12+#endif
13+#include <signal.h>
14+
15+/* The POSIX spec requires that use of pthread_attr_setstacksize
16+ be conditional on _POSIX_THREAD_ATTR_STACKSIZE being defined. */
17+#ifdef _POSIX_THREAD_ATTR_STACKSIZE
18+#ifndef THREAD_STACK_SIZE
19+#define THREAD_STACK_SIZE 0 /* use default stack size */
20+#endif
21+/* for safety, ensure a viable minimum stacksize */
22+#define THREAD_STACK_MIN 0x8000 /* 32kB */
23+#else /* !_POSIX_THREAD_ATTR_STACKSIZE */
24+#ifdef THREAD_STACK_SIZE
25+#error "THREAD_STACK_SIZE defined but _POSIX_THREAD_ATTR_STACKSIZE undefined"
26+#endif
27+#endif
28+
29+/* The POSIX spec says that implementations supporting the sem_*
30+ family of functions must indicate this by defining
31+ _POSIX_SEMAPHORES. */
32+#ifdef _POSIX_SEMAPHORES
33+/* On FreeBSD 4.x, _POSIX_SEMAPHORES is defined empty, so
34+ we need to add 0 to make it work there as well. */
35+#if (_POSIX_SEMAPHORES+0) == -1
36+#define HAVE_BROKEN_POSIX_SEMAPHORES
37+#else
38+#include <semaphore.h>
39+#include <errno.h>
40+#endif
41+#endif
42+
43+/* Before FreeBSD 5.4, system scope threads was very limited resource
44+ in default setting. So the process scope is preferred to get
45+ enough number of threads to work. */
46+#ifdef __FreeBSD__
47+#include <osreldate.h>
48+#if __FreeBSD_version >= 500000 && __FreeBSD_version < 504101
49+#undef PTHREAD_SYSTEM_SCHED_SUPPORTED
50+#endif
51+#endif
52+
53+#if !defined(pthread_attr_default)
54+# define pthread_attr_default ((pthread_attr_t *)NULL)
55+#endif
56+#if !defined(pthread_mutexattr_default)
57+# define pthread_mutexattr_default ((pthread_mutexattr_t *)NULL)
58+#endif
59+#if !defined(pthread_condattr_default)
60+# define pthread_condattr_default ((pthread_condattr_t *)NULL)
61+#endif
62+
63+
64+/* Whether or not to use semaphores directly rather than emulating them with
65+ * mutexes and condition variables:
66+ */
67+#if defined(_POSIX_SEMAPHORES) && !defined(HAVE_BROKEN_POSIX_SEMAPHORES)
68+# define USE_SEMAPHORES
69+#else
70+# undef USE_SEMAPHORES
71+#endif
72+
73+
74+/* On platforms that don't use standard POSIX threads pthread_sigmask()
75+ * isn't present. DEC threads uses sigprocmask() instead as do most
76+ * other UNIX International compliant systems that don't have the full
77+ * pthread implementation.
78+ */
79+#if defined(HAVE_PTHREAD_SIGMASK) && !defined(HAVE_BROKEN_PTHREAD_SIGMASK)
80+# define SET_THREAD_SIGMASK pthread_sigmask
81+#else
82+# define SET_THREAD_SIGMASK sigprocmask
83+#endif
84+
85+
86+/* A pthread mutex isn't sufficient to model the Python lock type
87+ * because, according to Draft 5 of the docs (P1003.4a/D5), both of the
88+ * following are undefined:
89+ * -> a thread tries to lock a mutex it already has locked
90+ * -> a thread tries to unlock a mutex locked by a different thread
91+ * pthread mutexes are designed for serializing threads over short pieces
92+ * of code anyway, so wouldn't be an appropriate implementation of
93+ * Python's locks regardless.
94+ *
95+ * The pthread_lock struct implements a Python lock as a "locked?" bit
96+ * and a <condition, mutex> pair. In general, if the bit can be acquired
97+ * instantly, it is, else the pair is used to block the thread until the
98+ * bit is cleared. 9 May 1994 tim@ksr.com
99+ */
100+
101+typedef struct {
102+ char locked; /* 0=unlocked, 1=locked */
103+ /* a <cond, mutex> pair to handle an acquire of a locked lock */
104+ pthread_cond_t lock_released;
105+ pthread_mutex_t mut;
106+} pthread_lock;
107+
108+#define CHECK_STATUS(name) if (status != 0) { perror(name); error = 1; }
109+
110+/*
111+ * Initialization.
112+ */
113+
114+#ifdef _HAVE_BSDI
115+static
116+void _noop(void)
117+{
118+}
119+
120+static void
121+PyThread__init_thread(void)
122+{
123+ /* DO AN INIT BY STARTING THE THREAD */
124+ static int dummy = 0;
125+ pthread_t thread1;
126+ pthread_create(&thread1, NULL, (void *) _noop, &dummy);
127+ pthread_join(thread1, NULL);
128+}
129+
130+#else /* !_HAVE_BSDI */
131+
132+static void
133+PyThread__init_thread(void)
134+{
135+#if defined(_AIX) && defined(__GNUC__)
136+ pthread_init();
137+#endif
138+}
139+
140+#endif /* !_HAVE_BSDI */
141+
142+/*
143+ * Thread support.
144+ */
145+
146+
147+long
148+PyThread_start_new_thread(void (*func)(void *), void *arg)
149+{
150+ pthread_t th;
151+ int status;
152+#if defined(THREAD_STACK_SIZE) || defined(PTHREAD_SYSTEM_SCHED_SUPPORTED)
153+ pthread_attr_t attrs;
154+#endif
155+#if defined(THREAD_STACK_SIZE)
156+ size_t tss;
157+#endif
158+
159+ dprintf(("PyThread_start_new_thread called\n"));
160+ if (!initialized)
161+ PyThread_init_thread();
162+
163+#if defined(THREAD_STACK_SIZE) || defined(PTHREAD_SYSTEM_SCHED_SUPPORTED)
164+ if (pthread_attr_init(&attrs) != 0)
165+ return -1;
166+#endif
167+#if defined(THREAD_STACK_SIZE)
168+ tss = (_pythread_stacksize != 0) ? _pythread_stacksize
169+ : THREAD_STACK_SIZE;
170+ if (tss != 0) {
171+ if (pthread_attr_setstacksize(&attrs, tss) != 0) {
172+ pthread_attr_destroy(&attrs);
173+ return -1;
174+ }
175+ }
176+#endif
177+#if defined(PTHREAD_SYSTEM_SCHED_SUPPORTED)
178+ pthread_attr_setscope(&attrs, PTHREAD_SCOPE_SYSTEM);
179+#endif
180+
181+ status = pthread_create(&th,
182+#if defined(THREAD_STACK_SIZE) || defined(PTHREAD_SYSTEM_SCHED_SUPPORTED)
183+ &attrs,
184+#else
185+ (pthread_attr_t*)NULL,
186+#endif
187+ (void* (*)(void *))func,
188+ (void *)arg
189+ );
190+
191+#if defined(THREAD_STACK_SIZE) || defined(PTHREAD_SYSTEM_SCHED_SUPPORTED)
192+ pthread_attr_destroy(&attrs);
193+#endif
194+ if (status != 0)
195+ return -1;
196+
197+ pthread_detach(th);
198+
199+#if SIZEOF_PTHREAD_T <= SIZEOF_LONG
200+ return (long) th;
201+#else
202+ return (long) *(long *) &th;
203+#endif
204+}
205+
206+/* XXX This implementation is considered (to quote Tim Peters) "inherently
207+ hosed" because:
208+ - It does not guarantee the promise that a non-zero integer is returned.
209+ - The cast to long is inherently unsafe.
210+ - It is not clear that the 'volatile' (for AIX?) and ugly casting in the
211+ latter return statement (for Alpha OSF/1) are any longer necessary.
212+*/
213+long
214+PyThread_get_thread_ident(void)
215+{
216+ volatile pthread_t threadid;
217+ if (!initialized)
218+ PyThread_init_thread();
219+ /* Jump through some hoops for Alpha OSF/1 */
220+ threadid = pthread_self();
221+#if SIZEOF_PTHREAD_T <= SIZEOF_LONG
222+ return (long) threadid;
223+#else
224+ return (long) *(long *) &threadid;
225+#endif
226+}
227+
228+static void
229+do_PyThread_exit_thread(int no_cleanup)
230+{
231+ dprintf(("PyThread_exit_thread called\n"));
232+ if (!initialized) {
233+ if (no_cleanup)
234+ _exit(0);
235+ else
236+ exit(0);
237+ }
238+}
239+
240+void
241+PyThread_exit_thread(void)
242+{
243+ do_PyThread_exit_thread(0);
244+}
245+
246+void
247+PyThread__exit_thread(void)
248+{
249+ do_PyThread_exit_thread(1);
250+}
251+
252+#ifndef NO_EXIT_PROG
253+static void
254+do_PyThread_exit_prog(int status, int no_cleanup)
255+{
256+ dprintf(("PyThread_exit_prog(%d) called\n", status));
257+ if (!initialized)
258+ if (no_cleanup)
259+ _exit(status);
260+ else
261+ exit(status);
262+}
263+
264+void
265+PyThread_exit_prog(int status)
266+{
267+ do_PyThread_exit_prog(status, 0);
268+}
269+
270+void
271+PyThread__exit_prog(int status)
272+{
273+ do_PyThread_exit_prog(status, 1);
274+}
275+#endif /* NO_EXIT_PROG */
276+
277+#ifdef USE_SEMAPHORES
278+
279+/*
280+ * Lock support.
281+ */
282+
283+PyThread_type_lock
284+PyThread_allocate_lock(void)
285+{
286+ sem_t *lock;
287+ int status, error = 0;
288+
289+ dprintf(("PyThread_allocate_lock called\n"));
290+ if (!initialized)
291+ PyThread_init_thread();
292+
293+ lock = (sem_t *)malloc(sizeof(sem_t));
294+
295+ if (lock) {
296+ status = sem_init(lock,0,1);
297+ CHECK_STATUS("sem_init");
298+
299+ if (error) {
300+ free((void *)lock);
301+ lock = NULL;
302+ }
303+ }
304+
305+ dprintf(("PyThread_allocate_lock() -> %p\n", lock));
306+ return (PyThread_type_lock)lock;
307+}
308+
309+void
310+PyThread_free_lock(PyThread_type_lock lock)
311+{
312+ sem_t *thelock = (sem_t *)lock;
313+ int status, error = 0;
314+
315+ dprintf(("PyThread_free_lock(%p) called\n", lock));
316+
317+ if (!thelock)
318+ return;
319+
320+ status = sem_destroy(thelock);
321+ CHECK_STATUS("sem_destroy");
322+
323+ free((void *)thelock);
324+}
325+
326+/*
327+ * As of February 2002, Cygwin thread implementations mistakenly report error
328+ * codes in the return value of the sem_ calls (like the pthread_ functions).
329+ * Correct implementations return -1 and put the code in errno. This supports
330+ * either.
331+ */
332+static int
333+fix_status(int status)
334+{
335+ return (status == -1) ? errno : status;
336+}
337+
338+int
339+PyThread_acquire_lock(PyThread_type_lock lock, int waitflag)
340+{
341+ int success;
342+ sem_t *thelock = (sem_t *)lock;
343+ int status, error = 0;
344+
345+ dprintf(("PyThread_acquire_lock(%p, %d) called\n", lock, waitflag));
346+
347+ do {
348+ if (waitflag)
349+ status = fix_status(sem_wait(thelock));
350+ else
351+ status = fix_status(sem_trywait(thelock));
352+ } while (status == EINTR); /* Retry if interrupted by a signal */
353+
354+ if (waitflag) {
355+ CHECK_STATUS("sem_wait");
356+ } else if (status != EAGAIN) {
357+ CHECK_STATUS("sem_trywait");
358+ }
359+
360+ success = (status == 0) ? 1 : 0;
361+
362+ dprintf(("PyThread_acquire_lock(%p, %d) -> %d\n", lock, waitflag, success));
363+ return success;
364+}
365+
366+void
367+PyThread_release_lock(PyThread_type_lock lock)
368+{
369+ sem_t *thelock = (sem_t *)lock;
370+ int status, error = 0;
371+
372+ dprintf(("PyThread_release_lock(%p) called\n", lock));
373+
374+ status = sem_post(thelock);
375+ CHECK_STATUS("sem_post");
376+}
377+
378+#else /* USE_SEMAPHORES */
379+
380+/*
381+ * Lock support.
382+ */
383+PyThread_type_lock
384+PyThread_allocate_lock(void)
385+{
386+ pthread_lock *lock;
387+ int status, error = 0;
388+
389+ dprintf(("PyThread_allocate_lock called\n"));
390+ if (!initialized)
391+ PyThread_init_thread();
392+
393+ lock = (pthread_lock *) malloc(sizeof(pthread_lock));
394+ if (lock) {
395+ memset((void *)lock, '\0', sizeof(pthread_lock));
396+ lock->locked = 0;
397+
398+ status = pthread_mutex_init(&lock->mut,
399+ pthread_mutexattr_default);
400+ CHECK_STATUS("pthread_mutex_init");
401+
402+ status = pthread_cond_init(&lock->lock_released,
403+ pthread_condattr_default);
404+ CHECK_STATUS("pthread_cond_init");
405+
406+ if (error) {
407+ free((void *)lock);
408+ lock = 0;
409+ }
410+ }
411+
412+ dprintf(("PyThread_allocate_lock() -> %p\n", lock));
413+ return (PyThread_type_lock) lock;
414+}
415+
416+void
417+PyThread_free_lock(PyThread_type_lock lock)
418+{
419+ pthread_lock *thelock = (pthread_lock *)lock;
420+ int status, error = 0;
421+
422+ dprintf(("PyThread_free_lock(%p) called\n", lock));
423+
424+ status = pthread_mutex_destroy( &thelock->mut );
425+ CHECK_STATUS("pthread_mutex_destroy");
426+
427+ status = pthread_cond_destroy( &thelock->lock_released );
428+ CHECK_STATUS("pthread_cond_destroy");
429+
430+ free((void *)thelock);
431+}
432+
433+int
434+PyThread_acquire_lock(PyThread_type_lock lock, int waitflag)
435+{
436+ int success;
437+ pthread_lock *thelock = (pthread_lock *)lock;
438+ int status, error = 0;
439+
440+ dprintf(("PyThread_acquire_lock(%p, %d) called\n", lock, waitflag));
441+
442+ status = pthread_mutex_lock( &thelock->mut );
443+ CHECK_STATUS("pthread_mutex_lock[1]");
444+ success = thelock->locked == 0;
445+
446+ if ( !success && waitflag ) {
447+ /* continue trying until we get the lock */
448+
449+ /* mut must be locked by me -- part of the condition
450+ * protocol */
451+ while ( thelock->locked ) {
452+ status = pthread_cond_wait(&thelock->lock_released,
453+ &thelock->mut);
454+ CHECK_STATUS("pthread_cond_wait");
455+ }
456+ success = 1;
457+ }
458+ if (success) thelock->locked = 1;
459+ status = pthread_mutex_unlock( &thelock->mut );
460+ CHECK_STATUS("pthread_mutex_unlock[1]");
461+
462+ if (error) success = 0;
463+ dprintf(("PyThread_acquire_lock(%p, %d) -> %d\n", lock, waitflag, success));
464+ return success;
465+}
466+
467+void
468+PyThread_release_lock(PyThread_type_lock lock)
469+{
470+ pthread_lock *thelock = (pthread_lock *)lock;
471+ int status, error = 0;
472+
473+ dprintf(("PyThread_release_lock(%p) called\n", lock));
474+
475+ status = pthread_mutex_lock( &thelock->mut );
476+ CHECK_STATUS("pthread_mutex_lock[3]");
477+
478+ thelock->locked = 0;
479+
480+ status = pthread_mutex_unlock( &thelock->mut );
481+ CHECK_STATUS("pthread_mutex_unlock[3]");
482+
483+ /* wake up someone (anyone, if any) waiting on the lock */
484+ status = pthread_cond_signal( &thelock->lock_released );
485+ CHECK_STATUS("pthread_cond_signal");
486+}
487+
488+#endif /* USE_SEMAPHORES */
489+
490+/* set the thread stack size.
491+ * Return 0 if size is valid, -1 if size is invalid,
492+ * -2 if setting stack size is not supported.
493+ */
494+static int
495+_pythread_pthread_set_stacksize(size_t size)
496+{
497+#if defined(THREAD_STACK_SIZE)
498+ pthread_attr_t attrs;
499+ size_t tss_min;
500+ int rc = 0;
501+#endif
502+
503+ /* set to default */
504+ if (size == 0) {
505+ _pythread_stacksize = 0;
506+ return 0;
507+ }
508+
509+#if defined(THREAD_STACK_SIZE)
510+#if defined(PTHREAD_STACK_MIN)
511+ tss_min = PTHREAD_STACK_MIN > THREAD_STACK_MIN ? PTHREAD_STACK_MIN
512+ : THREAD_STACK_MIN;
513+#else
514+ tss_min = THREAD_STACK_MIN;
515+#endif
516+ if (size >= tss_min) {
517+ /* validate stack size by setting thread attribute */
518+ if (pthread_attr_init(&attrs) == 0) {
519+ rc = pthread_attr_setstacksize(&attrs, size);
520+ pthread_attr_destroy(&attrs);
521+ if (rc == 0) {
522+ _pythread_stacksize = size;
523+ return 0;
524+ }
525+ }
526+ }
527+ return -1;
528+#else
529+ return -2;
530+#endif
531+}
532+
533+#define THREAD_SET_STACKSIZE(x) _pythread_pthread_set_stacksize(x)