3 * Copyright © 2020 František Kučera (Frantovo.cz, GlobalCode.info)
5 * This program is free software: you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation, version 3 of the License.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program. If not, see <http://www.gnu.org/licenses/>.
30 using Bytes = std::vector<uint8_t>;
32 class DJMFixImpl : public DJMFix {
34 MidiSender* midiSender;
35 std::thread keepAliveThread;
36 std::recursive_mutex midiMutex;
37 std::atomic<bool> running{false};
38 std::atomic<bool> stopped{false};
39 std::atomic<bool> sendKeepAlive{false};
44 std::cerr << "DJMFixImpl::run()" << std::endl; // TODO: do not mess STDIO
45 if (sendKeepAlive) send({0xf0, 0x00, 0x40, 0x05, 0x00, 0x00, 0x00, 0x17, 0x00, 0x50, 0x01, 0xf7});
46 std::this_thread::sleep_for(std::chrono::milliseconds(200));
50 void send(const MidiMessage& midiMessage) {
51 std::lock_guard<std::recursive_mutex> lock(midiMutex);
52 midiSender->send(midiMessage);
55 std::string toString(const Bytes& midiMessage) {
56 std::stringstream result;
57 for (uint8_t b : midiMessage) result << std::hex << std::setw(2) << std::setfill('0') << (int) b;
61 Bytes normalize(const Bytes& data) {
62 if (data.size() % 2) throw std::invalid_argument("data before normalization must have even number of bytes");
64 result.reserve(data.size() / 2);
65 for (size_t i = 0; i < data.size() / 2; i++) result.push_back((data[i * 2] & 0x0F) << 4 | (data[i * 2 + 1] & 0x0F));
69 Bytes denormalize(const Bytes& data) {
71 result.reserve(data.size()*2);
72 for (size_t i = 0; i < data.size(); i++) {
73 result.push_back(data[i] >> 4);
74 result.push_back(data[i] & 0x0F);
79 uint32_t fnv32hash(const Bytes& buff) {
80 uint32_t hash = 0x811c9dc5;
81 for (uint8_t b : buff) hash = ((b^hash) * 0x1000193);
85 Bytes toBytes(const uint32_t value) {
88 result.push_back(value >> 24);
89 result.push_back(value >> 16);
90 result.push_back(value >> 8);
91 result.push_back(value >> 0);
95 bool equals(Bytes a, Bytes b) {
96 if (a.size() != b.size()) return false;
97 for (size_t i = 0; i < a.size(); i++) if (a[i] != b[i]) return false;
101 template<typename T> std::vector<T> concat(const std::vector<T>& a, const std::vector<T>& b, const std::vector<T>& c = {}) {
102 std::vector<T> result;
103 result.reserve(a.size() + b.size() + c.size());
104 for (size_t i = 0; i < a.size(); i++) result.push_back(a[i]);
105 for (size_t i = 0; i < b.size(); i++) result.push_back(b[i]);
106 for (size_t i = 0; i < c.size(); i++) result.push_back(c[i]);
110 template<typename T> std::vector<T> xOR(const std::vector<T>& a, const std::vector<T>& b) {
111 if (a.size() != b.size()) throw std::invalid_argument("xor: both must be the same length");
112 std::vector<T> result;
113 result.reserve(a.size());
114 for (size_t i = 0; i < a.size(); i++) result.push_back(a[i] ^ b[i]);
120 virtual ~DJMFixImpl() override {
121 std::cerr << "~DJMFixImpl()" << std::endl; // TODO: do not mess STDIO
125 void setMidiSender(MidiSender* midiSender) {
126 std::cerr << "DJMFixImpl::setMidiSender()" << std::endl; // TODO: do not mess STDIO
127 this->midiSender = midiSender;
130 virtual void receive(const MidiMessage& midiMessage) override {
131 std::cerr << "DJMFixImpl::receive(): size = " << midiMessage.size() << " data = " << toString(midiMessage) << std::endl; // TODO: do not mess STDIO
132 std::lock_guard<std::recursive_mutex> lock(midiMutex);
135 if (midiMessage.size() == 12 && midiMessage[9] == 0x11) {
136 send({0xf0, 0x00, 0x40, 0x05, 0x00, 0x00, 0x00, 0x17, 0x00, 0x12, 0x2a, 0x01, 0x0b, 0x50, 0x69, 0x6f, 0x6e, 0x65, 0x65, 0x72, 0x44, 0x4a, 0x02, 0x0b, 0x72, 0x65, 0x6b, 0x6f, 0x72, 0x64, 0x62, 0x6f, 0x78, 0x03, 0x12, 0x02, 0x09, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0x03, 0x04, 0x08, 0x00, 0x00, 0x00, 0x00, 0xf7});
137 } else if (midiMessage.size() == 54 && midiMessage[9] == 0x13 && midiMessage[33] == 0x04 && midiMessage[43] == 0x03) {
138 Bytes hash1(midiMessage.begin() + 35, midiMessage.begin() + 35 + 8);
139 seed2 = Bytes(midiMessage.begin() + 45, midiMessage.begin() + 45 + 8);
140 hash1 = normalize(hash1);
141 seed2 = normalize(seed2);
142 std::cerr << "DJMFixImpl::receive(): got message with hash1 = " << toString(hash1) << " and seed2 = " << toString(seed2) << std::endl; // TODO: do not mess STDIO
144 Bytes seed0 = {0x68, 0x01, 0x31, 0xFB};
145 Bytes seed1 = {0x29, 0x00, 0x00, 0x00, 0x23, 0x48, 0x00, 0x00};
147 Bytes hash1check = toBytes(fnv32hash(concat(seed1, xOR(seed0, seed2))));
149 if (equals(hash1, hash1check)) {
150 std::cerr << "DJMFixImpl::receive(): hash1 verification: OK" << std::endl; // TODO: do not mess STDIO
151 Bytes hash2 = toBytes(fnv32hash(concat(seed2, xOR(seed0, seed2))));
152 send(concat({0xf0, 0x00, 0x40, 0x05, 0x00, 0x00, 0x00, 0x17, 0x00, 0x14, 0x38, 0x01, 0x0b, 0x50, 0x69, 0x6f, 0x6e, 0x65, 0x65, 0x72, 0x44, 0x4a, 0x02, 0x0b, 0x72, 0x65, 0x6b, 0x6f, 0x72, 0x64, 0x62, 0x6f, 0x78, 0x04, 0x0a}, concat(denormalize(hash2),{0x05, 0x16, 0x05, 0x09, 0x0b, 0x05, 0x04, 0x0b, 0x0f, 0x0e, 0x0e, 0x04, 0x04, 0x0a, 0x05, 0x0a, 0x0c, 0x08, 0x0e, 0x04, 0x0c, 0x05, 0xf7})));
155 << "DJMFixImpl::receive(): hash1 verification failed: "
156 << " midiMessage = " << toString(midiMessage)
157 << " seed0 = " << toString(seed0)
158 << " seed1 = " << toString(seed1)
159 << " seed2 = " << toString(seed2)
160 << " hash1 = " << toString(hash1)
161 << " hash1check = " << toString(hash1check)
163 // TODO: graceful death
165 } else if (midiMessage.size() == 12 && midiMessage[9] == 0x15) {
166 sendKeepAlive = true;
171 void start() override {
172 std::cerr << "DJMFixImpl::start()" << std::endl; // TODO: do not mess STDIO
173 if (midiSender == nullptr) throw std::logic_error("need a midiSender when starting DJMFix");
175 // TODO: methods for parsing and constructing messages from parts (TLV)
176 send({0xf0, 0x00, 0x40, 0x05, 0x00, 0x00, 0x00, 0x17, 0x00, 0x50, 0x01, 0xf7});
178 keepAliveThread = std::thread(&DJMFixImpl::run, this);
183 void stop() override {
185 keepAliveThread.join();
187 std::cerr << "DJMFixImpl::stop()" << std::endl; // TODO: do not mess STDIO
192 return new DJMFixImpl();