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-rw-r--r--media/libmedia/SingleStateQueue.cpp106
1 files changed, 0 insertions, 106 deletions
diff --git a/media/libmedia/SingleStateQueue.cpp b/media/libmedia/SingleStateQueue.cpp
deleted file mode 100644
index c241184..0000000
--- a/media/libmedia/SingleStateQueue.cpp
+++ /dev/null
@@ -1,106 +0,0 @@
-/*
- * Copyright (C) 2012 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include <new>
-#include <cutils/atomic.h>
-#include <media/SingleStateQueue.h>
-
-namespace android {
-
-template<typename T> SingleStateQueue<T>::Mutator::Mutator(Shared *shared)
- : mSequence(0), mShared((Shared *) shared)
-{
- // exactly one of Mutator and Observer must initialize, currently it is Observer
- //shared->init();
-}
-
-template<typename T> int32_t SingleStateQueue<T>::Mutator::push(const T& value)
-{
- Shared *shared = mShared;
- int32_t sequence = mSequence;
- sequence++;
- android_atomic_acquire_store(sequence, &shared->mSequence);
- shared->mValue = value;
- sequence++;
- android_atomic_release_store(sequence, &shared->mSequence);
- mSequence = sequence;
- // consider signalling a futex here, if we know that observer is waiting
- return sequence;
-}
-
-template<typename T> bool SingleStateQueue<T>::Mutator::ack()
-{
- return mShared->mAck - mSequence == 0;
-}
-
-template<typename T> bool SingleStateQueue<T>::Mutator::ack(int32_t sequence)
-{
- // this relies on 2's complement rollover to detect an ancient sequence number
- return mShared->mAck - sequence >= 0;
-}
-
-template<typename T> SingleStateQueue<T>::Observer::Observer(Shared *shared)
- : mSequence(0), mSeed(1), mShared((Shared *) shared)
-{
- // exactly one of Mutator and Observer must initialize, currently it is Observer
- shared->init();
-}
-
-template<typename T> bool SingleStateQueue<T>::Observer::poll(T& value)
-{
- Shared *shared = mShared;
- int32_t before = shared->mSequence;
- if (before == mSequence) {
- return false;
- }
- for (int tries = 0; ; ) {
- const int MAX_TRIES = 5;
- if (before & 1) {
- if (++tries >= MAX_TRIES) {
- return false;
- }
- before = shared->mSequence;
- } else {
- android_memory_barrier();
- T temp = shared->mValue;
- int32_t after = android_atomic_release_load(&shared->mSequence);
- if (after == before) {
- value = temp;
- shared->mAck = before;
- mSequence = before;
- return true;
- }
- if (++tries >= MAX_TRIES) {
- return false;
- }
- before = after;
- }
- }
-}
-
-#if 0
-template<typename T> SingleStateQueue<T>::SingleStateQueue(void /*Shared*/ *shared)
-{
- ((Shared *) shared)->init();
-}
-#endif
-
-} // namespace android
-
-// hack for gcc
-#ifdef SINGLE_STATE_QUEUE_INSTANTIATIONS
-#include SINGLE_STATE_QUEUE_INSTANTIATIONS
-#endif