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-rw-r--r--media/ffvpx/libavutil/atomic.c109
1 files changed, 109 insertions, 0 deletions
diff --git a/media/ffvpx/libavutil/atomic.c b/media/ffvpx/libavutil/atomic.c
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+++ b/media/ffvpx/libavutil/atomic.c
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+/*
+ * 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 */