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Diffstat (limited to 'media/ffvpx/libavutil/atomic.c')
-rw-r--r-- | media/ffvpx/libavutil/atomic.c | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/media/ffvpx/libavutil/atomic.c b/media/ffvpx/libavutil/atomic.c new file mode 100644 index 000000000..64cff2576 --- /dev/null +++ b/media/ffvpx/libavutil/atomic.c @@ -0,0 +1,109 @@ +/* + * Copyright (c) 2012 Ronald S. Bultje <rsbultje@gmail.com> + * + * This file is part of FFmpeg. + * + * FFmpeg 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 2.1 of the License, or (at your option) any later version. + * + * FFmpeg 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include "config.h" +#include "atomic.h" + +#if !HAVE_ATOMICS_NATIVE + +#if HAVE_PTHREADS + +#include <pthread.h> + +static pthread_mutex_t atomic_lock = PTHREAD_MUTEX_INITIALIZER; + +int avpriv_atomic_int_get(volatile int *ptr) +{ + int res; + + pthread_mutex_lock(&atomic_lock); + res = *ptr; + pthread_mutex_unlock(&atomic_lock); + + return res; +} + +void avpriv_atomic_int_set(volatile int *ptr, int val) +{ + pthread_mutex_lock(&atomic_lock); + *ptr = val; + pthread_mutex_unlock(&atomic_lock); +} + +int avpriv_atomic_int_add_and_fetch(volatile int *ptr, int inc) +{ + int res; + + pthread_mutex_lock(&atomic_lock); + *ptr += inc; + res = *ptr; + pthread_mutex_unlock(&atomic_lock); + + return res; +} + +void *avpriv_atomic_ptr_cas(void * volatile *ptr, void *oldval, void *newval) +{ + void *ret; + pthread_mutex_lock(&atomic_lock); + ret = *ptr; + if (ret == oldval) + *ptr = newval; + pthread_mutex_unlock(&atomic_lock); + return ret; +} + +#elif !HAVE_THREADS + +int avpriv_atomic_int_get(volatile int *ptr) +{ + return *ptr; +} + +void avpriv_atomic_int_set(volatile int *ptr, int val) +{ + *ptr = val; +} + +int avpriv_atomic_int_add_and_fetch(volatile int *ptr, int inc) +{ + *ptr += inc; + return *ptr; +} + +void *avpriv_atomic_ptr_cas(void * volatile *ptr, void *oldval, void *newval) +{ + if (*ptr == oldval) { + *ptr = newval; + return oldval; + } + return *ptr; +} + +#else /* HAVE_THREADS */ + +/* This should never trigger, unless a new threading implementation + * without correct atomics dependencies in configure or a corresponding + * atomics implementation is added. */ +#error "Threading is enabled, but there is no implementation of atomic operations available" + +#endif /* HAVE_PTHREADS */ + +#endif /* !HAVE_ATOMICS_NATIVE */ |