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#ifndef foopulseoncehfoo
#define foopulseoncehfoo
/* $Id$ */
/***
This file is part of PulseAudio.
Copyright 2006 Lennart Poettering
PulseAudio is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
PulseAudio is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with PulseAudio; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
USA.
***/
#include <pulsecore/mutex.h>
#include <pulsecore/atomic.h>
typedef struct pa_once {
pa_atomic_ptr_t mutex;
pa_atomic_t ref, done;
} pa_once;
#define PA_ONCE_INIT \
{ \
.mutex = PA_ATOMIC_PTR_INIT(NULL), \
.ref = PA_ATOMIC_INIT(0), \
.done = PA_ATOMIC_INIT(0) \
}
/* Not to be called directly, use the macros defined below instead */
int pa_once_begin(pa_once *o);
void pa_once_end(pa_once *o);
#define PA_ONCE_BEGIN \
do { \
static pa_once _once = PA_ONCE_INIT; \
if (pa_once_begin(&_once)) {{
#define PA_ONCE_END \
} \
pa_once_end(&_once); \
} \
} while(0)
/*
Usage of these macros is like this:
void foo() {
PA_ONCE_BEGIN {
... stuff to be called just once ...
} PA_ONCE_END;
}
*/
/* Same API but calls a function */
typedef void (*pa_once_func_t) (void);
void pa_run_once(pa_once *o, pa_once_func_t f);
#endif
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