diff --git a/media/libaaudio/tests/Android.mk b/media/libaaudio/tests/Android.mk
index 37b010d..8117181 100644
--- a/media/libaaudio/tests/Android.mk
+++ b/media/libaaudio/tests/Android.mk
@@ -80,3 +80,13 @@
 LOCAL_SHARED_LIBRARIES := libaaudio libbinder libcutils libutils
 LOCAL_MODULE := test_n_streams
 include $(BUILD_NATIVE_TEST)
+
+include $(CLEAR_VARS)
+LOCAL_C_INCLUDES := \
+    $(call include-path-for, audio-utils) \
+    frameworks/av/media/libaaudio/include \
+    frameworks/av/media/libaaudio/src
+LOCAL_SRC_FILES:= test_atomic_fifo.cpp
+LOCAL_SHARED_LIBRARIES := libaaudio libbinder libcutils libutils
+LOCAL_MODULE := test_atomic_fifo
+include $(BUILD_NATIVE_TEST)
diff --git a/media/libaaudio/tests/test_atomic_fifo.cpp b/media/libaaudio/tests/test_atomic_fifo.cpp
new file mode 100644
index 0000000..0edfebe
--- /dev/null
+++ b/media/libaaudio/tests/test_atomic_fifo.cpp
@@ -0,0 +1,388 @@
+/*
+ * Copyright (C) 2018 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 <iostream>
+
+#include <gtest/gtest.h>
+#include <stdlib.h>
+
+#include "fifo/FifoBuffer.h"
+#include "fifo/FifoController.h"
+
+using android::fifo_frames_t;
+using android::fifo_counter_t;
+using android::FifoController;
+using android::FifoBuffer;
+using android::WrappingBuffer;
+
+TEST(test_fifo_controller, fifo_indices) {
+    // Values are arbitrary primes designed to trigger edge cases.
+    constexpr int capacity = 83;
+    constexpr int threshold = 47;
+    FifoController   fifoController(capacity, threshold);
+    ASSERT_EQ(capacity, fifoController.getCapacity());
+    ASSERT_EQ(threshold, fifoController.getThreshold());
+
+    ASSERT_EQ(0, fifoController.getReadCounter());
+    ASSERT_EQ(0, fifoController.getWriteCounter());
+    ASSERT_EQ(0, fifoController.getFullFramesAvailable());
+    ASSERT_EQ(threshold, fifoController.getEmptyFramesAvailable());
+
+    // Pretend to write some data.
+    constexpr int advance1 = 23;
+    fifoController.advanceWriteIndex(advance1);
+    int advanced = advance1;
+    ASSERT_EQ(0, fifoController.getReadCounter());
+    ASSERT_EQ(0, fifoController.getReadIndex());
+    ASSERT_EQ(advanced, fifoController.getWriteCounter());
+    ASSERT_EQ(advanced, fifoController.getWriteIndex());
+    ASSERT_EQ(advanced, fifoController.getFullFramesAvailable());
+    ASSERT_EQ(threshold - advanced, fifoController.getEmptyFramesAvailable());
+
+    // Pretend to read the data.
+    fifoController.advanceReadIndex(advance1);
+    ASSERT_EQ(advanced, fifoController.getReadCounter());
+    ASSERT_EQ(advanced, fifoController.getReadIndex());
+    ASSERT_EQ(advanced, fifoController.getWriteCounter());
+    ASSERT_EQ(advanced, fifoController.getWriteIndex());
+    ASSERT_EQ(0, fifoController.getFullFramesAvailable());
+    ASSERT_EQ(threshold, fifoController.getEmptyFramesAvailable());
+
+    // Write past end of buffer.
+    constexpr int advance2 = 13 + capacity - advance1;
+    fifoController.advanceWriteIndex(advance2);
+    advanced += advance2;
+    ASSERT_EQ(advance1, fifoController.getReadCounter());
+    ASSERT_EQ(advance1, fifoController.getReadIndex());
+    ASSERT_EQ(advanced, fifoController.getWriteCounter());
+    ASSERT_EQ(advanced - capacity, fifoController.getWriteIndex());
+    ASSERT_EQ(advance2, fifoController.getFullFramesAvailable());
+    ASSERT_EQ(threshold - advance2, fifoController.getEmptyFramesAvailable());
+}
+
+TEST(test_fifo_controller, fifo_wrap_around_zero) {
+    constexpr int capacity = 7; // arbitrary prime
+    constexpr int threshold = capacity;
+    FifoController fifoController(capacity, threshold);
+    ASSERT_EQ(capacity, fifoController.getCapacity());
+    ASSERT_EQ(threshold, fifoController.getThreshold());
+
+    fifoController.setReadCounter(-10); // a bit less than negative capacity
+    for (int i = 0; i < 20; i++) {
+        EXPECT_EQ(i - 10, fifoController.getReadCounter());
+        EXPECT_GE(fifoController.getReadIndex(), 0);
+        EXPECT_LT(fifoController.getReadIndex(), capacity);
+        fifoController.advanceReadIndex(1);
+    }
+
+    fifoController.setWriteCounter(-10);
+    for (int i = 0; i < 20; i++) {
+        EXPECT_EQ(i - 10, fifoController.getWriteCounter());
+        EXPECT_GE(fifoController.getWriteIndex(), 0);
+        EXPECT_LT(fifoController.getWriteIndex(), capacity);
+        fifoController.advanceWriteIndex(1);
+    }
+}
+
+
+// TODO consider using a template for other data types.
+
+// Create a big array and then use a region in the middle for the  unit tests.
+// Then we can scan the rest of the array to see if it got clobbered.
+static constexpr fifo_frames_t kBigArraySize = 1024;
+static constexpr fifo_frames_t kFifoDataOffset = 128; // starting index of FIFO data
+static constexpr int16_t       kSafeDataValue = 0x7654; // original value of BigArray
+
+class TestFifoBuffer {
+public:
+    explicit TestFifoBuffer(fifo_frames_t capacity, fifo_frames_t threshold = 0)
+        : mFifoBuffer(sizeof(int16_t), capacity,
+                      &mReadIndex,
+                      &mWriteIndex,
+                      &mVeryBigArray[kFifoDataOffset]) // address of start of FIFO data
+    {
+
+        // Assume a frame is one int16_t.
+        // For reading and writing.
+        if (threshold <= 0) {
+            threshold = capacity;
+        }
+        mFifoBuffer.setThreshold(threshold);
+        mThreshold = threshold;
+
+        for (fifo_frames_t i = 0; i < kBigArraySize; i++) {
+            mVeryBigArray[i] = kSafeDataValue;
+        }
+    }
+
+    void checkMisc() {
+        ASSERT_EQ((int32_t)(2 * sizeof(int16_t)), mFifoBuffer.convertFramesToBytes(2));
+        ASSERT_EQ(mThreshold, mFifoBuffer.getThreshold());
+    }
+
+    void verifyAddressInRange(void *p, void *valid, size_t numBytes) {
+        uintptr_t p_int = (uintptr_t) p;
+        uintptr_t valid_int = (uintptr_t) valid;
+        EXPECT_GE(p_int, valid_int);
+        EXPECT_LT(p_int, (valid_int + numBytes));
+    }
+
+    void verifyStorageIntegrity() {
+        for (fifo_frames_t i = 0; i < kFifoDataOffset; i++) {
+            EXPECT_EQ(mVeryBigArray[i], kSafeDataValue);
+        }
+        fifo_frames_t firstFrameAfter = kFifoDataOffset + mFifoBuffer.getBufferCapacityInFrames();
+        for (fifo_frames_t i = firstFrameAfter; i < kBigArraySize; i++) {
+            EXPECT_EQ(mVeryBigArray[i], kSafeDataValue);
+        }
+    }
+
+    // Verify that the available frames in each part add up correctly.
+    void verifyWrappingBuffer() {
+        WrappingBuffer wrappingBuffer;
+
+
+        // Does the sum of the two parts match the available value returned?
+        // For EmptyRoom
+        fifo_frames_t framesAvailable =
+                mFifoBuffer.getFifoControllerBase()->getEmptyFramesAvailable();
+        fifo_frames_t wrapAvailable = mFifoBuffer.getEmptyRoomAvailable(&wrappingBuffer);
+        EXPECT_EQ(framesAvailable, wrapAvailable);
+        fifo_frames_t bothAvailable = wrappingBuffer.numFrames[0] + wrappingBuffer.numFrames[1];
+        EXPECT_EQ(framesAvailable, bothAvailable);
+        // For FullData
+        framesAvailable =
+                mFifoBuffer.getFifoControllerBase()->getFullFramesAvailable();
+        wrapAvailable = mFifoBuffer.getFullDataAvailable(&wrappingBuffer);
+        EXPECT_EQ(framesAvailable, wrapAvailable);
+        bothAvailable = wrappingBuffer.numFrames[0] + wrappingBuffer.numFrames[1];
+        EXPECT_EQ(framesAvailable, bothAvailable);
+
+        // Are frame counts in legal range?
+        fifo_frames_t capacity = mFifoBuffer.getBufferCapacityInFrames();
+        EXPECT_GE(wrappingBuffer.numFrames[0], 0);
+        EXPECT_LE(wrappingBuffer.numFrames[0], capacity);
+        EXPECT_GE(wrappingBuffer.numFrames[1], 0);
+        EXPECT_LE(wrappingBuffer.numFrames[1], capacity);
+
+        // Are addresses within the FIFO data area?
+        size_t validBytes = capacity * sizeof(int16_t);
+        if (wrappingBuffer.numFrames[0]) {
+            verifyAddressInRange(wrappingBuffer.data[0], mFifoStorage, validBytes);
+            uint8_t *last = ((uint8_t *)wrappingBuffer.data[0])
+                            + mFifoBuffer.convertFramesToBytes(wrappingBuffer.numFrames[0]) - 1;
+            verifyAddressInRange(last, mFifoStorage, validBytes);
+        }
+        if (wrappingBuffer.numFrames[1]) {
+            verifyAddressInRange(wrappingBuffer.data[1], mFifoStorage, validBytes);
+            uint8_t *last = ((uint8_t *)wrappingBuffer.data[1])
+                            + mFifoBuffer.convertFramesToBytes(wrappingBuffer.numFrames[1]) - 1;
+            verifyAddressInRange(last, mFifoStorage, validBytes);
+        }
+
+    }
+
+    // Write data but do not overflow.
+    void writeMultipleDataFrames(fifo_frames_t numFrames) {
+        fifo_frames_t framesAvailable =
+                mFifoBuffer.getFifoControllerBase()->getEmptyFramesAvailable();
+        fifo_frames_t framesToWrite = std::min(framesAvailable, numFrames);
+        for (int i = 0; i < framesToWrite; i++) {
+            mData[i] = mNextWriteIndex++;
+        }
+        fifo_frames_t actual = mFifoBuffer.write(mData, framesToWrite);
+        ASSERT_EQ(framesToWrite, actual);
+    }
+
+    // Read whatever data is available, Do not underflow.
+    void verifyMultipleDataFrames(fifo_frames_t numFrames) {
+        fifo_frames_t framesAvailable =
+                mFifoBuffer.getFifoControllerBase()->getFullFramesAvailable();
+        fifo_frames_t framesToRead = std::min(framesAvailable, numFrames);
+        fifo_frames_t actual = mFifoBuffer.read(mData, framesToRead);
+        ASSERT_EQ(framesToRead, actual);
+        for (int i = 0; i < framesToRead; i++) {
+            ASSERT_EQ(mNextVerifyIndex++, mData[i]);
+        }
+    }
+
+    // Read specified number of frames
+    void verifyRequestedData(fifo_frames_t numFrames) {
+        fifo_frames_t framesAvailable =
+                mFifoBuffer.getFifoControllerBase()->getFullFramesAvailable();
+        ASSERT_LE(numFrames, framesAvailable);
+        fifo_frames_t framesToRead = std::min(framesAvailable, numFrames);
+        fifo_frames_t actual = mFifoBuffer.read(mData, framesToRead);
+        ASSERT_EQ(actual, numFrames);
+        for (int i = 0; i < actual; i++) {
+            ASSERT_EQ(mNextVerifyIndex++, mData[i]);
+        }
+    }
+
+    // Wrap around the end of the buffer.
+    void checkWrappingWriteRead() {
+        constexpr int frames1 = 43;
+        constexpr int frames2 = 15;
+
+        writeMultipleDataFrames(frames1);
+        verifyWrappingBuffer();
+        verifyRequestedData(frames1);
+        verifyWrappingBuffer();
+
+        writeMultipleDataFrames(frames2);
+        verifyWrappingBuffer();
+        verifyRequestedData(frames2);
+        verifyWrappingBuffer();
+
+        verifyStorageIntegrity();
+    }
+
+    // Write and Read a specific amount of data.
+    void checkWriteRead() {
+        const fifo_frames_t capacity = mFifoBuffer.getBufferCapacityInFrames();
+        // Wrap around with the smaller region in the second half.
+        const int frames1 = capacity - 4;
+        const int frames2 = 7; // arbitrary, small
+        writeMultipleDataFrames(frames1);
+        verifyRequestedData(frames1);
+        writeMultipleDataFrames(frames2);
+        verifyRequestedData(frames2);
+
+        verifyStorageIntegrity();
+    }
+
+    // Write and Read a specific amount of data.
+    void checkWriteReadSmallLarge() {
+        const fifo_frames_t capacity = mFifoBuffer.getBufferCapacityInFrames();
+        // Wrap around with the larger region in the second half.
+        const int frames1 = capacity - 4;
+        const int frames2 = capacity - 9; // arbitrary, large
+        writeMultipleDataFrames(frames1);
+        verifyRequestedData(frames1);
+        writeMultipleDataFrames(frames2);
+        verifyRequestedData(frames2);
+
+        verifyStorageIntegrity();
+    }
+
+    // Randomly read or write up to the maximum amount of data.
+    void checkRandomWriteRead() {
+        for (int i = 0; i < 20; i++) {
+            fifo_frames_t framesEmpty =
+                    mFifoBuffer.getFifoControllerBase()->getEmptyFramesAvailable();
+            fifo_frames_t numFrames = (fifo_frames_t)(drand48() * framesEmpty);
+            writeMultipleDataFrames(numFrames);
+
+            fifo_frames_t framesFull =
+                    mFifoBuffer.getFifoControllerBase()->getFullFramesAvailable();
+            numFrames = (fifo_frames_t)(drand48() * framesFull);
+            verifyMultipleDataFrames(numFrames);
+        }
+
+        verifyStorageIntegrity();
+    }
+
+    // Write and Read a specific amount of data.
+    void checkNegativeCounters() {
+        fifo_counter_t counter = -9876;
+        mFifoBuffer.setWriteCounter(counter);
+        mFifoBuffer.setReadCounter(counter);
+        checkWrappingWriteRead();
+    }
+
+    // Wrap over the boundary at 0x7FFFFFFFFFFFFFFF
+    // Note that the behavior of a signed overflow is technically undefined.
+    void checkHalfWrap() {
+        fifo_counter_t counter = INT64_MAX - 10;
+        mFifoBuffer.setWriteCounter(counter);
+        mFifoBuffer.setReadCounter(counter);
+        ASSERT_GT(mFifoBuffer.getWriteCounter(), 0);
+        checkWrappingWriteRead();
+        ASSERT_LT(mFifoBuffer.getWriteCounter(), 0); // did we wrap past INT64_MAX?
+    }
+
+    // Wrap over the boundary at 0xFFFFFFFFFFFFFFFF
+    void checkFullWrap() {
+        fifo_counter_t counter = -10;
+        mFifoBuffer.setWriteCounter(counter);
+        mFifoBuffer.setReadCounter(counter);
+        ASSERT_LT(mFifoBuffer.getWriteCounter(), 0);
+        writeMultipleDataFrames(20);
+        ASSERT_GT(mFifoBuffer.getWriteCounter(), 0); // did we wrap past zero?
+        verifyStorageIntegrity();
+    }
+
+    FifoBuffer     mFifoBuffer;
+    fifo_frames_t  mNextWriteIndex = 0;
+    fifo_frames_t  mNextVerifyIndex = 0;
+    fifo_frames_t  mThreshold;
+
+    fifo_counter_t mReadIndex = 0;
+    fifo_counter_t mWriteIndex = 0;
+    int16_t        mVeryBigArray[kBigArraySize]; // Use the middle of this array for the FIFO.
+    int16_t       *mFifoStorage = &mVeryBigArray[kFifoDataOffset]; // Start here for storage.
+    int16_t        mData[kBigArraySize]{};
+};
+
+TEST(test_fifo_buffer, fifo_write_read) {
+    constexpr int capacity = 51; // arbitrary
+    TestFifoBuffer tester(capacity);
+    tester.checkMisc();
+    tester.checkWriteRead();
+}
+
+TEST(test_fifo_buffer, fifo_wrapping_write_read) {
+    constexpr int capacity = 59; // arbitrary, a little bigger this time
+    TestFifoBuffer tester(capacity);
+    tester.checkWrappingWriteRead();
+}
+
+TEST(test_fifo_buffer, fifo_read_write_small_large) {
+    constexpr int capacity = 51; // arbitrary
+    TestFifoBuffer tester(capacity);
+    tester.checkWriteReadSmallLarge();
+}
+
+TEST(test_fifo_buffer, fifo_random_read_write) {
+    constexpr int capacity = 51; // arbitrary
+    TestFifoBuffer tester(capacity);
+    tester.checkRandomWriteRead();
+}
+
+TEST(test_fifo_buffer, fifo_random_threshold) {
+    constexpr int capacity = 67; // arbitrary
+    constexpr int threshold = 37; // arbitrary
+    TestFifoBuffer tester(capacity, threshold);
+    tester.checkRandomWriteRead();
+}
+
+TEST(test_fifo_buffer, fifo_negative_counters) {
+    constexpr int capacity = 49; // arbitrary
+    TestFifoBuffer tester(capacity);
+    tester.checkNegativeCounters();
+}
+
+TEST(test_fifo_buffer, fifo_half_wrap) {
+    constexpr int capacity = 57; // arbitrary
+    TestFifoBuffer tester(capacity);
+    tester.checkHalfWrap();
+}
+
+TEST(test_fifo_buffer, fifo_full_wrap) {
+    constexpr int capacity = 57; // arbitrary
+    TestFifoBuffer tester(capacity);
+    tester.checkFullWrap();
+}