From 3426a399ccbaa60c03bf38f9fb788a6f12b888b0 Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Sat, 9 Sep 2006 22:55:51 +0000 Subject: implement trival pa_once API based on atomic operations git-svn-id: file:///home/lennart/svn/public/pulseaudio/trunk@1385 fefdeb5f-60dc-0310-8127-8f9354f1896f --- src/pulsecore/once.h | 42 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) create mode 100644 src/pulsecore/once.h diff --git a/src/pulsecore/once.h b/src/pulsecore/once.h new file mode 100644 index 00000000..a82a3c86 --- /dev/null +++ b/src/pulsecore/once.h @@ -0,0 +1,42 @@ +#ifndef foopulseoncehfoo +#define foopulseoncehfoo + +/* $Id$ */ + +/*** + This file is part of PulseAudio. + + 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 + +typedef struct pa_once { + pa_atomic_int_t atomic; +} pa_once_t; + +#define PA_ONCE_INIT { PA_ATOMIC_INIT(0) } + +#define pa_once_test(o) (pa_atomic_cmpxchg(&(o)->atomic, 0, 1)) + +typedef void (*pa_once_func_t) (void); + +static inline void pa_once(pa_once_t *o, pa_once_func_t f) { + if (pa_once_test(o)) + f(); +} + +#endif -- cgit