audiopolicy: Use C++11 atomics, factor out handle generation
Update the code to use C++11 atomics. Make sure that
unsigned ints are used as id counters (signed ints have undefined
overflow behavior). Factor out common code from AudioPatch
and AudioPort.
Test: compiles
Change-Id: Ic359e97795a6282a2937d88bead8a1de27c8db7a
diff --git a/services/audiopolicy/common/managerdefinitions/include/AudioPatch.h b/services/audiopolicy/common/managerdefinitions/include/AudioPatch.h
index 385f257..b82b846 100644
--- a/services/audiopolicy/common/managerdefinitions/include/AudioPatch.h
+++ b/services/audiopolicy/common/managerdefinitions/include/AudioPatch.h
@@ -16,6 +16,7 @@
#pragma once
+#include "HandleGenerator.h"
#include <system/audio.h>
#include <utils/Errors.h>
#include <utils/RefBase.h>
@@ -24,7 +25,7 @@
namespace android {
-class AudioPatch : public RefBase
+class AudioPatch : public RefBase, private HandleGenerator<audio_patch_handle_t>
{
public:
AudioPatch(const struct audio_patch *patch, uid_t uid);
@@ -35,9 +36,6 @@
struct audio_patch mPatch;
uid_t mUid;
audio_patch_handle_t mAfPatchHandle;
-
-private:
- static volatile int32_t mNextUniqueId;
};
class AudioPatchCollection : public DefaultKeyedVector<audio_patch_handle_t, sp<AudioPatch> >
diff --git a/services/audiopolicy/common/managerdefinitions/include/AudioPort.h b/services/audiopolicy/common/managerdefinitions/include/AudioPort.h
index 4f79ed2..c0a2f4c 100644
--- a/services/audiopolicy/common/managerdefinitions/include/AudioPort.h
+++ b/services/audiopolicy/common/managerdefinitions/include/AudioPort.h
@@ -18,6 +18,7 @@
#include "AudioCollections.h"
#include "AudioProfile.h"
+#include "HandleGenerator.h"
#include <utils/String8.h>
#include <utils/Vector.h>
#include <utils/RefBase.h>
@@ -32,7 +33,7 @@
class AudioRoute;
typedef Vector<sp<AudioGain> > AudioGainCollection;
-class AudioPort : public virtual RefBase
+class AudioPort : public virtual RefBase, private HandleGenerator<audio_port_handle_t>
{
public:
AudioPort(const String8& name, audio_port_type_t type, audio_port_role_t role) :
@@ -152,7 +153,6 @@
uint32_t mFlags; // attribute flags mask (e.g primary output, direct output...).
AudioProfileVector mProfiles; // AudioProfiles supported by this port (format, Rates, Channels)
AudioRouteVector mRoutes; // Routes involving this port
- static volatile int32_t mNextUniqueId;
};
class AudioPortConfig : public virtual RefBase
diff --git a/services/audiopolicy/common/managerdefinitions/include/HandleGenerator.h b/services/audiopolicy/common/managerdefinitions/include/HandleGenerator.h
new file mode 100644
index 0000000..737a2e0
--- /dev/null
+++ b/services/audiopolicy/common/managerdefinitions/include/HandleGenerator.h
@@ -0,0 +1,40 @@
+/*
+ * Copyright (C) 2017 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.
+ */
+
+#pragma once
+
+#include <atomic>
+#include <limits>
+
+namespace android {
+
+template<typename T>
+class HandleGenerator {
+ protected:
+ static T getNextHandle();
+};
+
+template<typename T>
+T HandleGenerator<T>::getNextHandle() {
+ static std::atomic<uint32_t> mNextUniqueId(1);
+ uint32_t id = mNextUniqueId++;
+ while (id > std::numeric_limits<T>::max()) {
+ id -= std::numeric_limits<T>::max();
+ }
+ return static_cast<T>(id);
+}
+
+} // namespace android
diff --git a/services/audiopolicy/common/managerdefinitions/src/AudioPatch.cpp b/services/audiopolicy/common/managerdefinitions/src/AudioPatch.cpp
index 32606ea..e79ffde 100644
--- a/services/audiopolicy/common/managerdefinitions/src/AudioPatch.cpp
+++ b/services/audiopolicy/common/managerdefinitions/src/AudioPatch.cpp
@@ -22,15 +22,12 @@
#include "TypeConverter.h"
#include <log/log.h>
-#include <cutils/atomic.h>
#include <utils/String8.h>
namespace android {
-int32_t volatile AudioPatch::mNextUniqueId = 1;
-
AudioPatch::AudioPatch(const struct audio_patch *patch, uid_t uid) :
- mHandle(static_cast<audio_patch_handle_t>(android_atomic_inc(&mNextUniqueId))),
+ mHandle(HandleGenerator<audio_patch_handle_t>::getNextHandle()),
mPatch(*patch),
mUid(uid),
mAfPatchHandle(AUDIO_PATCH_HANDLE_NONE)
diff --git a/services/audiopolicy/common/managerdefinitions/src/AudioPort.cpp b/services/audiopolicy/common/managerdefinitions/src/AudioPort.cpp
index 6807ea5..164f6c6 100644
--- a/services/audiopolicy/common/managerdefinitions/src/AudioPort.cpp
+++ b/services/audiopolicy/common/managerdefinitions/src/AudioPort.cpp
@@ -21,7 +21,6 @@
#include "HwModule.h"
#include "AudioGain.h"
#include <policy.h>
-#include <cutils/atomic.h>
#ifndef ARRAY_SIZE
#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
@@ -29,8 +28,6 @@
namespace android {
-int32_t volatile AudioPort::mNextUniqueId = 1;
-
// --- AudioPort class implementation
void AudioPort::attach(const sp<HwModule>& module)
{
@@ -40,7 +37,7 @@
// Note that is a different namespace than AudioFlinger unique IDs
audio_port_handle_t AudioPort::getNextUniqueId()
{
- return static_cast<audio_port_handle_t>(android_atomic_inc(&mNextUniqueId));
+ return getNextHandle();
}
audio_module_handle_t AudioPort::getModuleHandle() const
diff --git a/services/audiopolicy/managerdefault/AudioPolicyManager.cpp b/services/audiopolicy/managerdefault/AudioPolicyManager.cpp
index b717419..f680866 100644
--- a/services/audiopolicy/managerdefault/AudioPolicyManager.cpp
+++ b/services/audiopolicy/managerdefault/AudioPolicyManager.cpp
@@ -32,7 +32,6 @@
#include <AudioPolicyManagerInterface.h>
#include <AudioPolicyEngineInstance.h>
-#include <cutils/atomic.h>
#include <cutils/properties.h>
#include <utils/Log.h>
#include <media/AudioParameter.h>
@@ -3437,7 +3436,7 @@
// ----------------------------------------------------------------------------
uint32_t AudioPolicyManager::nextAudioPortGeneration()
{
- return android_atomic_inc(&mAudioPortGeneration);
+ return mAudioPortGeneration++;
}
#ifdef USE_XML_AUDIO_POLICY_CONF
diff --git a/services/audiopolicy/managerdefault/AudioPolicyManager.h b/services/audiopolicy/managerdefault/AudioPolicyManager.h
index b61bc2d..ae2e7c3 100644
--- a/services/audiopolicy/managerdefault/AudioPolicyManager.h
+++ b/services/audiopolicy/managerdefault/AudioPolicyManager.h
@@ -16,6 +16,8 @@
#pragma once
+#include <atomic>
+
#include <stdint.h>
#include <sys/types.h>
#include <cutils/config_utils.h>
@@ -534,7 +536,7 @@
HwModuleCollection mHwModulesAll; // normally not needed, used during construction and for
// dumps
- volatile int32_t mAudioPortGeneration;
+ std::atomic<uint32_t> mAudioPortGeneration;
AudioPatchCollection mAudioPatches;