| 0,0 → 1,123 |
|---|
| /* |
| * 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 "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 (*ptr == 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 |
| |
| #error "Threading is enabled, but there is no implementation of atomic operations available" |
| |
| #endif /* HAVE_PTHREADS */ |
| |
| #endif /* !HAVE_MEMORYBARRIER && !HAVE_SYNC_VAL_COMPARE_AND_SWAP && !HAVE_MACHINE_RW_BARRIER */ |
| |
| #ifdef TEST |
| #include "avassert.h" |
| |
| int main(void) |
| { |
| volatile int val = 1; |
| int res; |
| |
| res = avpriv_atomic_int_add_and_fetch(&val, 1); |
| av_assert0(res == 2); |
| avpriv_atomic_int_set(&val, 3); |
| res = avpriv_atomic_int_get(&val); |
| av_assert0(res == 3); |
| |
| return 0; |
| } |
| #endif |