1 #include "midi_mapper.h"
2 #include "midi_mapping.pb.h"
4 #include <alsa/asoundlib.h>
5 #include <google/protobuf/text_format.h>
6 #include <google/protobuf/io/zero_copy_stream.h>
7 #include <google/protobuf/io/zero_copy_stream_impl.h>
9 #include <sys/eventfd.h>
14 using namespace google::protobuf;
16 using namespace std::placeholders;
20 double map_controller_to_float(int val)
22 // Slightly hackish mapping so that we can represent exactly 0.0, 0.5 and 1.0.
25 } else if (val >= 127) {
28 return (val + 0.5) / 127.0;
34 MIDIMapper::MIDIMapper(ControllerReceiver *receiver)
35 : receiver(receiver), mapping_proto(new MIDIMappingProto)
37 should_quit_fd = eventfd(/*initval=*/0, /*flags=*/0);
38 assert(should_quit_fd != -1);
41 MIDIMapper::~MIDIMapper()
44 const uint64_t one = 1;
45 write(should_quit_fd, &one, sizeof(one));
47 close(should_quit_fd);
50 bool load_midi_mapping_from_file(const string &filename, MIDIMappingProto *new_mapping)
52 // Read and parse the protobuf from disk.
53 int fd = open(filename.c_str(), O_RDONLY);
55 perror(filename.c_str());
58 io::FileInputStream input(fd); // Takes ownership of fd.
59 if (!TextFormat::Parse(&input, new_mapping)) {
67 void MIDIMapper::set_midi_mapping(const MIDIMappingProto &new_mapping)
70 mapping_proto->CopyFrom(new_mapping);
72 mapping_proto.reset(new MIDIMappingProto(new_mapping));
75 num_controller_banks = min(max(mapping_proto->num_controller_banks(), 1), 5);
76 current_controller_bank = 0;
79 void MIDIMapper::start_thread()
81 midi_thread = thread(&MIDIMapper::thread_func, this);
84 #define RETURN_ON_ERROR(msg, expr) do { \
87 fprintf(stderr, msg ": %s\n", snd_strerror(err)); \
93 void MIDIMapper::thread_func()
98 RETURN_ON_ERROR("snd_seq_open", snd_seq_open(&seq, "default", SND_SEQ_OPEN_DUPLEX, 0));
99 RETURN_ON_ERROR("snd_seq_nonblock", snd_seq_nonblock(seq, 1));
100 RETURN_ON_ERROR("snd_seq_client_name", snd_seq_set_client_name(seq, "nageru"));
101 RETURN_ON_ERROR("snd_seq_create_simple_port",
102 snd_seq_create_simple_port(seq, "nageru",
103 SND_SEQ_PORT_CAP_WRITE |
104 SND_SEQ_PORT_CAP_SUBS_WRITE,
105 SND_SEQ_PORT_TYPE_MIDI_GENERIC |
106 SND_SEQ_PORT_TYPE_APPLICATION));
108 // Listen to the announce port (0:1), which will tell us about new ports.
109 RETURN_ON_ERROR("snd_seq_connect_from", snd_seq_connect_from(seq, 0, /*client=*/0, /*port=*/1));
111 // Now go through all ports and subscribe to them.
112 snd_seq_client_info_t *cinfo;
113 snd_seq_client_info_alloca(&cinfo);
115 snd_seq_client_info_set_client(cinfo, -1);
116 while (snd_seq_query_next_client(seq, cinfo) >= 0) {
117 int client = snd_seq_client_info_get_client(cinfo);
119 snd_seq_port_info_t *pinfo;
120 snd_seq_port_info_alloca(&pinfo);
122 snd_seq_port_info_set_client(pinfo, client);
123 snd_seq_port_info_set_port(pinfo, -1);
124 while (snd_seq_query_next_port(seq, pinfo) >= 0) {
125 constexpr int mask = SND_SEQ_PORT_CAP_READ | SND_SEQ_PORT_CAP_SUBS_READ;
126 if ((snd_seq_port_info_get_capability(pinfo) & mask) == mask) {
127 subscribe_to_port(seq, *snd_seq_port_info_get_addr(pinfo));
132 int num_alsa_fds = snd_seq_poll_descriptors_count(seq, POLLIN);
133 unique_ptr<pollfd[]> fds(new pollfd[num_alsa_fds + 1]);
135 while (!should_quit) {
136 snd_seq_poll_descriptors(seq, fds.get(), num_alsa_fds, POLLIN);
137 fds[num_alsa_fds].fd = should_quit_fd;
138 fds[num_alsa_fds].events = POLLIN;
139 fds[num_alsa_fds].revents = 0;
141 err = poll(fds.get(), num_alsa_fds + 1, -1);
142 if (err == 0 || (err == -1 && errno == EINTR)) {
149 if (fds[num_alsa_fds].revents) {
150 // Activity on should_quit_fd.
154 // Seemingly we can get multiple events in a single poll,
155 // and if we don't handle them all, poll will _not_ alert us!
156 while (!should_quit) {
157 snd_seq_event_t *event;
158 err = snd_seq_event_input(seq, &event);
160 if (err == -EINTR) continue;
161 if (err == -EAGAIN) break;
162 fprintf(stderr, "snd_seq_event_input: %s\n", snd_strerror(err));
166 handle_event(seq, event);
172 void MIDIMapper::handle_event(snd_seq_t *seq, snd_seq_event_t *event)
174 switch (event->type) {
175 case SND_SEQ_EVENT_CONTROLLER: {
176 printf("Controller %d changed to %d\n", event->data.control.param, event->data.control.value);
178 const int controller = event->data.control.param;
179 const float value = map_controller_to_float(event->data.control.value);
181 // Global controllers.
182 match_controller(controller, MIDIMappingBusProto::kLocutFieldNumber, MIDIMappingProto::kLocutBankFieldNumber,
183 value, bind(&ControllerReceiver::set_locut, receiver, _2));
184 match_controller(controller, MIDIMappingBusProto::kLimiterThresholdFieldNumber, MIDIMappingProto::kLimiterThresholdBankFieldNumber,
185 value, bind(&ControllerReceiver::set_limiter_threshold, receiver, _2));
186 match_controller(controller, MIDIMappingBusProto::kMakeupGainFieldNumber, MIDIMappingProto::kMakeupGainBankFieldNumber,
187 value, bind(&ControllerReceiver::set_makeup_gain, receiver, _2));
190 match_controller(controller, MIDIMappingBusProto::kTrebleFieldNumber, MIDIMappingProto::kTrebleBankFieldNumber,
191 value, bind(&ControllerReceiver::set_treble, receiver, _1, _2));
192 match_controller(controller, MIDIMappingBusProto::kMidFieldNumber, MIDIMappingProto::kMidBankFieldNumber,
193 value, bind(&ControllerReceiver::set_mid, receiver, _1, _2));
194 match_controller(controller, MIDIMappingBusProto::kBassFieldNumber, MIDIMappingProto::kBassBankFieldNumber,
195 value, bind(&ControllerReceiver::set_bass, receiver, _1, _2));
196 match_controller(controller, MIDIMappingBusProto::kGainFieldNumber, MIDIMappingProto::kGainBankFieldNumber,
197 value, bind(&ControllerReceiver::set_gain, receiver, _1, _2));
198 match_controller(controller, MIDIMappingBusProto::kCompressorThresholdFieldNumber, MIDIMappingProto::kCompressorThresholdBankFieldNumber,
199 value, bind(&ControllerReceiver::set_compressor_threshold, receiver, _1, _2));
200 match_controller(controller, MIDIMappingBusProto::kFaderFieldNumber, MIDIMappingProto::kFaderBankFieldNumber,
201 value, bind(&ControllerReceiver::set_fader, receiver, _1, _2));
204 case SND_SEQ_EVENT_NOTEON: {
205 const int note = event->data.note.note;
207 printf("Note: %d\n", note);
209 // Bank change commands. TODO: Highlight the bank change in the UI.
210 for (size_t bus_idx = 0; bus_idx < size_t(mapping_proto->bus_mapping_size()); ++bus_idx) {
211 const MIDIMappingBusProto &bus_mapping = mapping_proto->bus_mapping(bus_idx);
212 if (bus_mapping.has_prev_bank() &&
213 bus_mapping.prev_bank().note_number() == note) {
214 current_controller_bank = (current_controller_bank + num_controller_banks - 1) % num_controller_banks;
216 if (bus_mapping.has_next_bank() &&
217 bus_mapping.next_bank().note_number() == note) {
218 current_controller_bank = (current_controller_bank + 1) % num_controller_banks;
220 if (bus_mapping.has_select_bank_1() &&
221 bus_mapping.select_bank_1().note_number() == note) {
222 current_controller_bank = 0;
224 if (bus_mapping.has_select_bank_2() &&
225 bus_mapping.select_bank_2().note_number() == note &&
226 num_controller_banks >= 2) {
227 current_controller_bank = 1;
229 if (bus_mapping.has_select_bank_3() &&
230 bus_mapping.select_bank_3().note_number() == note &&
231 num_controller_banks >= 3) {
232 current_controller_bank = 2;
234 if (bus_mapping.has_select_bank_4() &&
235 bus_mapping.select_bank_4().note_number() == note &&
236 num_controller_banks >= 4) {
237 current_controller_bank = 3;
239 if (bus_mapping.has_select_bank_5() &&
240 bus_mapping.select_bank_5().note_number() == note &&
241 num_controller_banks >= 5) {
242 current_controller_bank = 4;
246 match_button(note, MIDIMappingBusProto::kToggleLocutFieldNumber, MIDIMappingProto::kToggleLocutBankFieldNumber,
247 bind(&ControllerReceiver::toggle_locut, receiver, _1));
248 match_button(note, MIDIMappingBusProto::kToggleAutoGainStagingFieldNumber, MIDIMappingProto::kToggleAutoGainStagingBankFieldNumber,
249 bind(&ControllerReceiver::toggle_auto_gain_staging, receiver, _1));
250 match_button(note, MIDIMappingBusProto::kToggleCompressorFieldNumber, MIDIMappingProto::kToggleCompressorBankFieldNumber,
251 bind(&ControllerReceiver::toggle_compressor, receiver, _1));
252 match_button(note, MIDIMappingBusProto::kClearPeakFieldNumber, MIDIMappingProto::kClearPeakBankFieldNumber,
253 bind(&ControllerReceiver::clear_peak, receiver, _1));
255 case SND_SEQ_EVENT_PORT_START:
256 subscribe_to_port(seq, event->data.addr);
258 case SND_SEQ_EVENT_PORT_EXIT:
259 printf("MIDI port %d:%d went away.\n", event->data.addr.client, event->data.addr.port);
261 case SND_SEQ_EVENT_NOTEOFF:
262 case SND_SEQ_EVENT_CLIENT_START:
263 case SND_SEQ_EVENT_CLIENT_EXIT:
264 case SND_SEQ_EVENT_CLIENT_CHANGE:
265 case SND_SEQ_EVENT_PORT_CHANGE:
266 case SND_SEQ_EVENT_PORT_SUBSCRIBED:
267 case SND_SEQ_EVENT_PORT_UNSUBSCRIBED:
270 printf("Ignoring MIDI event of unknown type %d.\n", event->type);
274 void MIDIMapper::subscribe_to_port(snd_seq_t *seq, const snd_seq_addr_t &addr)
276 // Client 0 is basically the system; ignore it.
277 if (addr.client == 0) {
281 int err = snd_seq_connect_from(seq, 0, addr.client, addr.port);
283 // Just print out a warning (i.e., don't die); it could
284 // very well just be e.g. another application.
285 printf("Couldn't subscribe to MIDI port %d:%d (%s).\n",
286 addr.client, addr.port, snd_strerror(err));
288 printf("Subscribed to MIDI port %d:%d.\n", addr.client, addr.port);
292 void MIDIMapper::match_controller(int controller, int field_number, int bank_field_number, float value, function<void(unsigned, float)> func)
294 if (bank_mismatch(bank_field_number)) {
298 for (size_t bus_idx = 0; bus_idx < size_t(mapping_proto->bus_mapping_size()); ++bus_idx) {
299 const MIDIMappingBusProto &bus_mapping = mapping_proto->bus_mapping(bus_idx);
301 const FieldDescriptor *descriptor = bus_mapping.GetDescriptor()->FindFieldByNumber(field_number);
302 const Reflection *bus_reflection = bus_mapping.GetReflection();
303 if (!bus_reflection->HasField(bus_mapping, descriptor)) {
306 const MIDIControllerProto &controller_proto =
307 static_cast<const MIDIControllerProto &>(bus_reflection->GetMessage(bus_mapping, descriptor));
308 if (controller_proto.controller_number() == controller) {
309 func(bus_idx, value);
314 void MIDIMapper::match_button(int note, int field_number, int bank_field_number, function<void(unsigned)> func)
316 if (bank_mismatch(bank_field_number)) {
320 for (size_t bus_idx = 0; bus_idx < size_t(mapping_proto->bus_mapping_size()); ++bus_idx) {
321 const MIDIMappingBusProto &bus_mapping = mapping_proto->bus_mapping(bus_idx);
323 const FieldDescriptor *descriptor = bus_mapping.GetDescriptor()->FindFieldByNumber(field_number);
324 const Reflection *bus_reflection = bus_mapping.GetReflection();
325 if (!bus_reflection->HasField(bus_mapping, descriptor)) {
328 const MIDIButtonProto &button_proto =
329 static_cast<const MIDIButtonProto &>(bus_reflection->GetMessage(bus_mapping, descriptor));
330 if (button_proto.note_number() == note) {
336 bool MIDIMapper::bank_mismatch(int bank_field_number)
338 const FieldDescriptor *bank_descriptor = mapping_proto->GetDescriptor()->FindFieldByNumber(bank_field_number);
339 const Reflection *reflection = mapping_proto->GetReflection();
340 return (reflection->HasField(*mapping_proto, bank_descriptor) &&
341 reflection->GetInt32(*mapping_proto, bank_descriptor) != current_controller_bank);