diff options
Diffstat (limited to 'src/pulsecore/once.h')
| -rw-r--r-- | src/pulsecore/once.h | 58 |
1 files changed, 47 insertions, 11 deletions
diff --git a/src/pulsecore/once.h b/src/pulsecore/once.h index 0aabb3f2..576d40fa 100644 --- a/src/pulsecore/once.h +++ b/src/pulsecore/once.h @@ -1,21 +1,21 @@ #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 @@ -23,16 +23,52 @@ ***/ #include <pulsecore/mutex.h> +#include <pulsecore/atomic.h> typedef struct pa_once { - unsigned int once_value; - pa_mutex *mutex; -} pa_once_t; + pa_atomic_ptr_t mutex; + pa_atomic_t ref, done; +} pa_once; -#define PA_ONCE_INIT { .once_value = 0, .mutex = NULL } +#define PA_ONCE_INIT \ + { \ + .mutex = PA_ATOMIC_PTR_INIT(NULL), \ + .ref = PA_ATOMIC_INIT(0), \ + .done = PA_ATOMIC_INIT(0) \ + } -typedef void (*pa_once_func_t) (void); +/* 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) -void pa_once(pa_once_t *o, pa_once_func_t f); +/* + + 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 |