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Merge HUGE set of changes temporarily into a branch, to allow me to move them from one machine to another (lock-free and stuff)

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git-svn-id: file:///home/lennart/svn/public/pulseaudio/branches/lennart@1469 fefdeb5f-60dc-0310-8127-8f9354f1896f
This commit is contained in:
Lennart Poettering 2007-06-11 12:08:37 +00:00
parent 6aeec56708
commit 00da37f2c4
72 changed files with 4389 additions and 1767 deletions
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68
src/pulsecore/once-posix.c
View file

@ -26,44 +26,56 @@
#endif
#include <pthread.h>
#include <assert.h>
#include <pulsecore/macro.h>
#include <pulsecore/mutex.h>
#include "once.h"
#define ASSERT_SUCCESS(x) do { \
int _r = (x); \
assert(_r == 0); \
} while(0)
static pa_mutex *global_mutex;
static pthread_once_t global_mutex_once = PTHREAD_ONCE_INIT;
static void global_mutex_once_func(void) {
global_mutex = pa_mutex_new(0);
}
/* Not reentrant -- how could it be? */
void pa_once(pa_once_t *control, pa_once_func_t func) {
assert(control);
assert(func);
pa_mutex *m;
pa_assert(control);
pa_assert(func);
/* Create the global mutex */
ASSERT_SUCCESS(pthread_once(&global_mutex_once, global_mutex_once_func));
if (pa_atomic_load(&control->done))
return;
pa_atomic_inc(&control->ref);
for (;;) {
if ((m = pa_atomic_ptr_load(&control->mutex))) {
/* Create the local mutex */
pa_mutex_lock(global_mutex);
if (!control->mutex)
control->mutex = pa_mutex_new(1);
pa_mutex_unlock(global_mutex);
/* The mutex is stored in locked state, hence let's just
* wait until it is unlocked */
pa_mutex_lock(m);
pa_mutex_unlock(m);
break;
}
/* Execute function */
pa_mutex_lock(control->mutex);
if (!control->once_value) {
control->once_value = 1;
func();
pa_assert_se(m = pa_mutex_new(0));
pa_mutex_lock(m);
if (pa_atomic_ptr_cmpxchg(&control->mutex, NULL, m)) {
func();
pa_atomic_store(&control->done, 1);
pa_mutex_unlock(m);
break;
}
pa_mutex_unlock(m);
pa_mutex_free(m);
}
pa_assert(pa_atomic_load(&control->done));
if (pa_atomic_dec(&control->ref) <= 1) {
pa_assert(pa_atomic_ptr_cmpxchg(&control->mutex, m, NULL));
pa_mutex_free(m);
}
pa_mutex_unlock(control->mutex);
/* Caveat: We have to make sure that the once func has completed
* before returning, even if the once func is not actually