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Diffstat (limited to 'third_party/aom/aom_ports/aom_once.h')
-rw-r--r--third_party/aom/aom_ports/aom_once.h41
1 files changed, 19 insertions, 22 deletions
diff --git a/third_party/aom/aom_ports/aom_once.h b/third_party/aom/aom_ports/aom_once.h
index bb1e213668..8e04f8583d 100644
--- a/third_party/aom/aom_ports/aom_once.h
+++ b/third_party/aom/aom_ports/aom_once.h
@@ -17,7 +17,7 @@
/* Implement a function wrapper to guarantee initialization
* thread-safety for library singletons.
*
- * NOTE: These functions use static locks, and can only be
+ * NOTE: This function uses static locks, and can only be
* used with one common argument per compilation unit. So
*
* file1.c:
@@ -25,8 +25,8 @@
* ...
* aom_once(foo);
*
- * file2.c:
- * aom_once(bar);
+ * file2.c:
+ * aom_once(bar);
*
* will ensure foo() and bar() are each called only once, but in
*
@@ -46,19 +46,19 @@
* local initializers are not thread-safe in MSVC prior to Visual
* Studio 2015.
*
- * As a static, once_state will be zero-initialized as program start.
+ * As a static, aom_once_state will be zero-initialized as program start.
*/
-static LONG once_state;
-static void once(void (*func)(void)) {
- /* Try to advance once_state from its initial value of 0 to 1.
+static LONG aom_once_state;
+static void aom_once(void (*func)(void)) {
+ /* Try to advance aom_once_state from its initial value of 0 to 1.
* Only one thread can succeed in doing so.
*/
- if (InterlockedCompareExchange(&once_state, 1, 0) == 0) {
- /* We're the winning thread, having set once_state to 1.
+ if (InterlockedCompareExchange(&aom_once_state, 1, 0) == 0) {
+ /* We're the winning thread, having set aom_once_state to 1.
* Call our function. */
func();
- /* Now advance once_state to 2, unblocking any other threads. */
- InterlockedIncrement(&once_state);
+ /* Now advance aom_once_state to 2, unblocking any other threads. */
+ InterlockedIncrement(&aom_once_state);
return;
}
@@ -66,10 +66,10 @@ static void once(void (*func)(void)) {
* the state variable so we don't return before func()
* has finished executing elsewhere.
*
- * Try to advance once_state from 2 to 2, which is only possible
+ * Try to advance aom_once_state from 2 to 2, which is only possible
* after the winning thead advances it from 1 to 2.
*/
- while (InterlockedCompareExchange(&once_state, 2, 2) != 2) {
+ while (InterlockedCompareExchange(&aom_once_state, 2, 2) != 2) {
/* State isn't yet 2. Try again.
*
* We are used for singleton initialization functions,
@@ -83,8 +83,8 @@ static void once(void (*func)(void)) {
Sleep(0);
}
- /* We've seen once_state advance to 2, so we know func()
- * has been called. And we've left once_state as we found it,
+ /* We've seen aom_once_state advance to 2, so we know func()
+ * has been called. And we've left aom_once_state as we found it,
* so other threads will have the same experience.
*
* It's safe to return now.
@@ -95,7 +95,7 @@ static void once(void (*func)(void)) {
#elif CONFIG_MULTITHREAD && defined(__OS2__)
#define INCL_DOS
#include <os2.h>
-static void once(void (*func)(void)) {
+static void aom_once(void (*func)(void)) {
static int done;
/* If the initialization is complete, return early. */
@@ -117,18 +117,15 @@ static void once(void (*func)(void)) {
#elif CONFIG_MULTITHREAD && HAVE_PTHREAD_H
#include <pthread.h>
-static void once(void (*func)(void)) {
+static void aom_once(void (*func)(void)) {
static pthread_once_t lock = PTHREAD_ONCE_INIT;
pthread_once(&lock, func);
}
#else
-/* No-op version that performs no synchronization. *_rtcd() is idempotent,
- * so as long as your platform provides atomic loads/stores of pointers
- * no synchronization is strictly necessary.
- */
+/* Default version that performs no synchronization. */
-static void once(void (*func)(void)) {
+static void aom_once(void (*func)(void)) {
static int done;
if (!done) {