Move BlockingQueue.h to libinput
This is already useful in several places, and it's going to be also
useful in the future when InputConsumer is refactored.
So let's move it to include/input.
Bug: 311142655
Test: m inputflinger_blocking_queue_fuzzer
Change-Id: Idfc492c6bfc3cccab7e0b0d12b21a41a954cc44b
diff --git a/libs/input/tests/BlockingQueue_test.cpp b/libs/input/tests/BlockingQueue_test.cpp
new file mode 100644
index 0000000..924b937
--- /dev/null
+++ b/libs/input/tests/BlockingQueue_test.cpp
@@ -0,0 +1,154 @@
+/*
+ * Copyright (C) 2019 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 <input/BlockingQueue.h>
+
+#include <gtest/gtest.h>
+#include <thread>
+
+namespace android {
+
+using std::chrono_literals::operator""ns;
+
+// --- BlockingQueueTest ---
+
+/**
+ * Validate basic pop and push operation.
+ */
+TEST(BlockingQueueTest, Queue_AddAndRemove) {
+ constexpr size_t capacity = 10;
+ BlockingQueue<int> queue(capacity);
+
+ ASSERT_TRUE(queue.push(1));
+ ASSERT_EQ(queue.pop(), 1);
+
+ ASSERT_TRUE(queue.emplace(2));
+ ASSERT_EQ(queue.popWithTimeout(0ns), 2);
+
+ ASSERT_TRUE(queue.push(3));
+ ASSERT_EQ(queue.popWithTimeout(100ns), 3);
+
+ ASSERT_EQ(std::nullopt, queue.popWithTimeout(0ns));
+}
+
+/**
+ * Make sure the queue has strict capacity limits.
+ */
+TEST(BlockingQueueTest, Queue_ReachesCapacity) {
+ constexpr size_t capacity = 3;
+ BlockingQueue<int> queue(capacity);
+
+ // First 3 elements should be added successfully
+ ASSERT_TRUE(queue.push(1));
+ ASSERT_TRUE(queue.push(2));
+ ASSERT_TRUE(queue.push(3));
+ ASSERT_FALSE(queue.push(4)) << "Queue should reach capacity at size " << capacity;
+}
+
+/**
+ * Make sure the queue maintains FIFO order.
+ * Add elements and remove them, and check the order.
+ */
+TEST(BlockingQueueTest, Queue_isFIFO) {
+ constexpr size_t capacity = 10;
+ BlockingQueue<int> queue(capacity);
+
+ for (size_t i = 0; i < capacity; i++) {
+ ASSERT_TRUE(queue.push(static_cast<int>(i)));
+ }
+ for (size_t i = 0; i < capacity; i++) {
+ ASSERT_EQ(queue.pop(), static_cast<int>(i));
+ }
+}
+
+TEST(BlockingQueueTest, Queue_Clears) {
+ constexpr size_t capacity = 2;
+ BlockingQueue<int> queue(capacity);
+
+ queue.push(1);
+ queue.push(2);
+ queue.clear();
+ queue.push(3);
+ // Should no longer receive elements 1 and 2
+ ASSERT_EQ(3, queue.pop());
+}
+
+TEST(BlockingQueueTest, Queue_Erases) {
+ constexpr size_t capacity = 4;
+ BlockingQueue<int> queue(capacity);
+
+ queue.push(1);
+ queue.push(2);
+ queue.push(3);
+ queue.push(4);
+ // Erase elements 2 and 4
+ queue.erase_if([](int element) { return element == 2 || element == 4; });
+ // Should no longer receive elements 2 and 4
+ ASSERT_EQ(1, queue.pop());
+ ASSERT_EQ(3, queue.pop());
+}
+
+// --- BlockingQueueTest - Multiple threads ---
+
+TEST(BlockingQueueTest, Queue_AllowsMultipleThreads) {
+ constexpr size_t capacity = 100; // large capacity to increase likelihood that threads overlap
+ BlockingQueue<int> queue(capacity);
+
+ // Fill queue from a different thread
+ std::thread fillQueue([&queue]() {
+ for (size_t i = 0; i < capacity; i++) {
+ ASSERT_TRUE(queue.push(static_cast<int>(i)));
+ }
+ });
+
+ // Make sure all elements are received in correct order
+ for (size_t i = 0; i < capacity; i++) {
+ ASSERT_EQ(queue.pop(), static_cast<int>(i));
+ }
+
+ fillQueue.join();
+}
+
+/**
+ * When the queue has no elements, and pop is called, it should block
+ * the current thread until an element is added to the queue (from another thread).
+ * Here we create a separate thread and call pop on an empty queue. Next,
+ * we check that the thread is blocked.
+ */
+TEST(BlockingQueueTest, Queue_BlocksWhileWaitingForElements) {
+ constexpr size_t capacity = 1;
+ BlockingQueue<int> queue(capacity);
+
+ std::atomic_bool hasReceivedElement = false;
+
+ // fill queue from a different thread
+ std::thread waitUntilHasElements([&queue, &hasReceivedElement]() {
+ queue.pop(); // This should block until an element has been added
+ hasReceivedElement = true;
+ });
+
+ ASSERT_FALSE(hasReceivedElement);
+ queue.push(1);
+ waitUntilHasElements.join();
+ ASSERT_TRUE(hasReceivedElement);
+}
+
+TEST(BlockingQueueTest, Queue_TimesOut) {
+ BlockingQueue<int> queue;
+ ASSERT_EQ(std::nullopt, queue.popWithTimeout(1ns));
+}
+
+} // namespace android