Merge sc-dev-plus-aosp-without-vendor@7634622

Merged-In: Ifa71accba7ecf2ab15980227a4413831cfceb187
Change-Id: I7fb44c6c578a51c8ad36649d20a46233fd9609ca

1 files changed, 68 insertions, 0 deletions

diff --git a/biometrics/fingerprint/aidl/default/WorkerThread.cpp b/biometrics/fingerprint/aidl/default/WorkerThread.cpp
new file mode 100644
index 0000000000..d1a63d07ee
--- /dev/null
+++ b/biometrics/fingerprint/aidl/default/WorkerThread.cpp
@@ -0,0 +1,68 @@
+/*
+ * Copyright (C) 2021 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 "WorkerThread.h"
+
+namespace aidl::android::hardware::biometrics::fingerprint {
+
+// It's important that mThread is initialized after everything else because it runs a member
+// function that may use any member of this class.
+WorkerThread::WorkerThread(size_t maxQueueSize)
+    : mMaxSize(maxQueueSize),
+      mIsDestructing(false),
+      mQueue(),
+      mQueueMutex(),
+      mQueueCond(),
+      mThread(&WorkerThread::threadFunc, this) {}
+
+WorkerThread::~WorkerThread() {
+    // This is a signal for threadFunc to terminate as soon as possible, and a hint for schedule
+    // that it doesn't need to do any work.
+    mIsDestructing = true;
+    mQueueCond.notify_all();
+    mThread.join();
+}
+
+bool WorkerThread::schedule(std::unique_ptr<Callable> task) {
+    if (mIsDestructing) {
+        return false;
+    }
+
+    std::unique_lock<std::mutex> lock(mQueueMutex);
+    if (mQueue.size() >= mMaxSize) {
+        return false;
+    }
+    mQueue.push_back(std::move(task));
+    lock.unlock();
+    mQueueCond.notify_one();
+    return true;
+}
+
+void WorkerThread::threadFunc() {
+    while (!mIsDestructing) {
+        std::unique_lock<std::mutex> lock(mQueueMutex);
+        mQueueCond.wait(lock, [this] { return !mQueue.empty() || mIsDestructing; });
+        if (mIsDestructing) {
+            return;
+        }
+        std::unique_ptr<Callable> task = std::move(mQueue.front());
+        mQueue.pop_front();
+        lock.unlock();
+        (*task)();
+    }
+}
+
+}  // namespace aidl::android::hardware::biometrics::fingerprint