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-rw-r--r--vp8/common/rtcd.c69
1 files changed, 69 insertions, 0 deletions
diff --git a/vp8/common/rtcd.c b/vp8/common/rtcd.c
new file mode 100644
index 000000000..4980f48ad
--- /dev/null
+++ b/vp8/common/rtcd.c
@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2011 The WebM project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+#include "vpx_config.h"
+#define RTCD_C
+#include "vpx_rtcd.h"
+
+#if CONFIG_MULTITHREAD && HAVE_PTHREAD_H
+#include <pthread.h>
+static void once(void (*func)(void))
+{
+ static pthread_once_t lock = PTHREAD_ONCE_INIT;
+ pthread_once(&lock, func);
+}
+
+
+#elif CONFIG_MULTITHREAD && defined(_WIN32)
+#include <windows.h>
+static void once(void (*func)(void))
+{
+ /* Using a static initializer here rather than InitializeCriticalSection()
+ * since there's no race-free context in which to execute it. Protecting
+ * it with an atomic op like InterlockedCompareExchangePointer introduces
+ * an x86 dependency, and InitOnceExecuteOnce requires Vista.
+ */
+ static CRITICAL_SECTION lock = {(void *)-1, -1, 0, 0, 0, 0};
+ static int done;
+
+ EnterCriticalSection(&lock);
+
+ if (!done)
+ {
+ func();
+ done = 1;
+ }
+
+ LeaveCriticalSection(&lock);
+}
+
+
+#else
+/* No-op version that performs no synchronization. vpx_rtcd() is idempotent,
+ * so as long as your platform provides atomic loads/stores of pointers
+ * no synchronization is strictly necessary.
+ */
+
+static void once(void (*func)(void))
+{
+ static int done;
+
+ if(!done)
+ {
+ func();
+ done = 1;
+ }
+}
+#endif
+
+
+void vpx_rtcd()
+{
+ once(setup_rtcd_internal);
+}