/*
* 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.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.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.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.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.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.getEmptyFramesAvailable();
fifo_frames_t numFrames = (fifo_frames_t)(drand48() * framesEmpty);
writeMultipleDataFrames(numFrames);
fifo_frames_t framesFull =
mFifoBuffer.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();
}