Add a simple ring buffer and use it for holding TFLite model inputs.
Bug: 167946763
Test: atest libinput_tests
Change-Id: I7e50d38ed0c593aebc5fdc6af4b25868505d48bc
diff --git a/libs/input/tests/RingBuffer_test.cpp b/libs/input/tests/RingBuffer_test.cpp
new file mode 100644
index 0000000..8a6ef4c
--- /dev/null
+++ b/libs/input/tests/RingBuffer_test.cpp
@@ -0,0 +1,208 @@
+/*
+ * Copyright (C) 2023 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 <algorithm>
+#include <iterator>
+#include <memory>
+#include <vector>
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+#include <input/RingBuffer.h>
+
+namespace android {
+namespace {
+
+using ::testing::ElementsAre;
+using ::testing::ElementsAreArray;
+using ::testing::IsEmpty;
+using ::testing::Not;
+using ::testing::SizeIs;
+
+TEST(RingBufferTest, PushPop) {
+ RingBuffer<int> buffer(/*capacity=*/3);
+
+ buffer.pushBack(1);
+ buffer.pushBack(2);
+ buffer.pushBack(3);
+ EXPECT_THAT(buffer, ElementsAre(1, 2, 3));
+
+ buffer.pushBack(4);
+ EXPECT_THAT(buffer, ElementsAre(2, 3, 4));
+
+ buffer.pushFront(1);
+ EXPECT_THAT(buffer, ElementsAre(1, 2, 3));
+
+ EXPECT_EQ(1, buffer.popFront());
+ EXPECT_THAT(buffer, ElementsAre(2, 3));
+
+ buffer.pushBack(4);
+ EXPECT_THAT(buffer, ElementsAre(2, 3, 4));
+
+ buffer.pushBack(5);
+ EXPECT_THAT(buffer, ElementsAre(3, 4, 5));
+
+ EXPECT_EQ(5, buffer.popBack());
+ EXPECT_THAT(buffer, ElementsAre(3, 4));
+
+ EXPECT_EQ(4, buffer.popBack());
+ EXPECT_THAT(buffer, ElementsAre(3));
+
+ EXPECT_EQ(3, buffer.popBack());
+ EXPECT_THAT(buffer, ElementsAre());
+
+ buffer.pushBack(1);
+ EXPECT_THAT(buffer, ElementsAre(1));
+
+ EXPECT_EQ(1, buffer.popFront());
+ EXPECT_THAT(buffer, ElementsAre());
+}
+
+TEST(RingBufferTest, ObjectType) {
+ RingBuffer<std::unique_ptr<int>> buffer(/*capacity=*/2);
+ buffer.pushBack(std::make_unique<int>(1));
+ buffer.pushBack(std::make_unique<int>(2));
+ buffer.pushBack(std::make_unique<int>(3));
+
+ EXPECT_EQ(2, *buffer[0]);
+ EXPECT_EQ(3, *buffer[1]);
+}
+
+TEST(RingBufferTest, ConstructConstantValue) {
+ RingBuffer<int> buffer(/*count=*/3, /*value=*/10);
+ EXPECT_THAT(buffer, ElementsAre(10, 10, 10));
+ EXPECT_EQ(3u, buffer.capacity());
+}
+
+TEST(RingBufferTest, Assignment) {
+ RingBuffer<int> a(/*capacity=*/2);
+ a.pushBack(1);
+ a.pushBack(2);
+
+ RingBuffer<int> b(/*capacity=*/3);
+ b.pushBack(10);
+ b.pushBack(20);
+ b.pushBack(30);
+
+ std::swap(a, b);
+ EXPECT_THAT(a, ElementsAre(10, 20, 30));
+ EXPECT_THAT(b, ElementsAre(1, 2));
+
+ a = b;
+ EXPECT_THAT(a, ElementsAreArray(b));
+
+ RingBuffer<int> c(b);
+ EXPECT_THAT(c, ElementsAreArray(b));
+
+ RingBuffer<int> d(std::move(b));
+ EXPECT_EQ(0u, b.capacity());
+ EXPECT_THAT(b, ElementsAre());
+ EXPECT_THAT(d, ElementsAre(1, 2));
+
+ b = std::move(d);
+ EXPECT_THAT(b, ElementsAre(1, 2));
+ EXPECT_THAT(d, ElementsAre());
+ EXPECT_EQ(0u, d.capacity());
+}
+
+TEST(RingBufferTest, Subscripting) {
+ RingBuffer<int> buffer(/*capacity=*/2);
+ buffer.pushBack(1);
+ EXPECT_EQ(1, buffer[0]);
+
+ buffer.pushFront(0);
+ EXPECT_EQ(0, buffer[0]);
+ EXPECT_EQ(1, buffer[1]);
+
+ buffer.pushFront(-1);
+ EXPECT_EQ(-1, buffer[0]);
+ EXPECT_EQ(0, buffer[1]);
+}
+
+TEST(RingBufferTest, Iterator) {
+ RingBuffer<int> buffer(/*capacity=*/3);
+ buffer.pushFront(2);
+ buffer.pushBack(3);
+
+ auto begin = buffer.begin();
+ auto end = buffer.end();
+
+ EXPECT_NE(begin, end);
+ EXPECT_LE(begin, end);
+ EXPECT_GT(end, begin);
+ EXPECT_EQ(end, begin + 2);
+ EXPECT_EQ(begin, end - 2);
+
+ EXPECT_EQ(2, end - begin);
+ EXPECT_EQ(1, end - (begin + 1));
+
+ EXPECT_EQ(2, *begin);
+ ++begin;
+ EXPECT_EQ(3, *begin);
+ --begin;
+ EXPECT_EQ(2, *begin);
+ begin += 1;
+ EXPECT_EQ(3, *begin);
+ begin += -1;
+ EXPECT_EQ(2, *begin);
+ begin -= -1;
+ EXPECT_EQ(3, *begin);
+}
+
+TEST(RingBufferTest, Clear) {
+ RingBuffer<int> buffer(/*capacity=*/2);
+ EXPECT_THAT(buffer, ElementsAre());
+
+ buffer.pushBack(1);
+ EXPECT_THAT(buffer, ElementsAre(1));
+
+ buffer.clear();
+ EXPECT_THAT(buffer, ElementsAre());
+ EXPECT_THAT(buffer, SizeIs(0));
+ EXPECT_THAT(buffer, IsEmpty());
+
+ buffer.pushFront(1);
+ EXPECT_THAT(buffer, ElementsAre(1));
+}
+
+TEST(RingBufferTest, SizeAndIsEmpty) {
+ RingBuffer<int> buffer(/*capacity=*/2);
+ EXPECT_THAT(buffer, SizeIs(0));
+ EXPECT_THAT(buffer, IsEmpty());
+
+ buffer.pushBack(1);
+ EXPECT_THAT(buffer, SizeIs(1));
+ EXPECT_THAT(buffer, Not(IsEmpty()));
+
+ buffer.pushBack(2);
+ EXPECT_THAT(buffer, SizeIs(2));
+ EXPECT_THAT(buffer, Not(IsEmpty()));
+
+ buffer.pushBack(3);
+ EXPECT_THAT(buffer, SizeIs(2));
+ EXPECT_THAT(buffer, Not(IsEmpty()));
+
+ buffer.popFront();
+ EXPECT_THAT(buffer, SizeIs(1));
+ EXPECT_THAT(buffer, Not(IsEmpty()));
+
+ buffer.popBack();
+ EXPECT_THAT(buffer, SizeIs(0));
+ EXPECT_THAT(buffer, IsEmpty());
+}
+
+} // namespace
+} // namespace android