1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253 | /**************************************************************************/
/* midi_driver_alsamidi.cpp */
/**************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/**************************************************************************/
/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/**************************************************************************/
#ifdef ALSAMIDI_ENABLED
#include "midi_driver_alsamidi.h"
#include "core/os/os.h"
#include "core/print_string.h"
#include <errno.h>
MIDIDriverALSAMidi::MessageCategory MIDIDriverALSAMidi::msg_category(uint8_t msg_part) {
if (msg_part >= 0xf8) {
return MessageCategory::RealTime;
} else if (msg_part >= 0xf0) {
// System Exclusive begin/end are specified as System Common Category messages,
// but we separate them here and give them their own categories as their
// behaviour is significantly different.
if (msg_part == 0xf0) {
return MessageCategory::SysExBegin;
} else if (msg_part == 0xf7) {
return MessageCategory::SysExEnd;
}
return MessageCategory::SystemCommon;
} else if (msg_part >= 0x80) {
return MessageCategory::Voice;
}
return MessageCategory::Data;
}
size_t MIDIDriverALSAMidi::msg_expected_data(uint8_t status_byte) {
if (msg_category(status_byte) == MessageCategory::Voice) {
// Voice messages have a channel number in the status byte, mask it out.
status_byte &= 0xf0;
}
switch (status_byte) {
case 0x80: // Note Off
case 0x90: // Note On
case 0xA0: // Polyphonic Key Pressure (Aftertouch)
case 0xB0: // Control Change (CC)
case 0xE0: // Pitch Bend Change
case 0xF2: // Song Position Pointer
return 2;
case 0xC0: // Program Change
case 0xD0: // Channel Pressure (Aftertouch)
case 0xF1: // MIDI Time Code Quarter Frame
case 0xF3: // Song Select
return 1;
}
return 0;
}
void MIDIDriverALSAMidi::InputConnection::parse_byte(uint8_t byte, MIDIDriverALSAMidi &driver,
uint64_t timestamp) {
switch (msg_category(byte)) {
case MessageCategory::RealTime:
// Real-Time messages are single byte messages that can
// occur at any point.
// We pass them straight through.
driver.receive_input_packet(timestamp, &byte, 1);
break;
case MessageCategory::Data:
// We don't currently forward System Exclusive messages so skip their data.
// Collect any expected data for other message types.
if (!skipping_sys_ex && expected_data > received_data) {
buffer[received_data + 1] = byte;
received_data++;
// Forward a complete message and reset relevant state.
if (received_data == expected_data) {
driver.receive_input_packet(timestamp, buffer, received_data + 1);
received_data = 0;
if (msg_category(buffer[0]) != MessageCategory::Voice) {
// Voice Category messages can be sent with "running status".
// This means they don't resend the status byte until it changes.
// For other categories, we reset expected data, to require a new status byte.
expected_data = 0;
}
}
}
break;
case MessageCategory::SysExBegin:
buffer[0] = byte;
skipping_sys_ex = true;
break;
case MessageCategory::SysExEnd:
expected_data = 0;
skipping_sys_ex = false;
break;
case MessageCategory::Voice:
case MessageCategory::SystemCommon:
buffer[0] = byte;
received_data = 0;
expected_data = msg_expected_data(byte);
skipping_sys_ex = false;
if (expected_data == 0) {
driver.receive_input_packet(timestamp, &byte, 1);
}
break;
}
}
int MIDIDriverALSAMidi::InputConnection::read_in(MIDIDriverALSAMidi &driver, uint64_t timestamp) {
int ret;
do {
uint8_t byte = 0;
ret = snd_rawmidi_read(rawmidi_ptr, &byte, 1);
if (ret < 0) {
if (ret != -EAGAIN) {
ERR_PRINT("snd_rawmidi_read error: " + String(snd_strerror(ret)));
}
} else {
parse_byte(byte, driver, timestamp);
}
} while (ret > 0);
return ret;
}
void MIDIDriverALSAMidi::thread_func(void *p_udata) {
MIDIDriverALSAMidi *md = (MIDIDriverALSAMidi *)p_udata;<--- C-style pointer casting [+]C-style pointer casting detected. C++ offers four different kinds of casts as replacements: static_cast, const_cast, dynamic_cast and reinterpret_cast. A C-style cast could evaluate to any of those automatically, thus it is considered safer if the programmer explicitly states which kind of cast is expected. See also: https://www.securecoding.cert.org/confluence/display/cplusplus/EXP05-CPP.+Do+not+use+C-style+casts.
uint64_t timestamp = 0;
while (!md->exit_thread.is_set()) {
md->lock();
InputConnection *connections = md->connected_inputs.ptrw();
size_t connection_count = md->connected_inputs.size();
for (size_t i = 0; i < connection_count; i++) {
connections[i].read_in(*md, timestamp);
}
md->unlock();
OS::get_singleton()->delay_usec(1000);
}
}
Error MIDIDriverALSAMidi::open() {
void **hints;
if (snd_device_name_hint(-1, "rawmidi", &hints) < 0) {
return ERR_CANT_OPEN;
}
int i = 0;
for (void **n = hints; *n != nullptr; n++) {
char *name = snd_device_name_get_hint(*n, "NAME");
if (name != nullptr) {
snd_rawmidi_t *midi_in;
int ret = snd_rawmidi_open(&midi_in, nullptr, name, SND_RAWMIDI_NONBLOCK);
if (ret >= 0) {
connected_inputs.insert(i++, InputConnection(midi_in));
}
}
if (name != nullptr) {
free(name);
}
}
snd_device_name_free_hint(hints);
exit_thread.clear();
thread.start(MIDIDriverALSAMidi::thread_func, this);
return OK;
}
void MIDIDriverALSAMidi::close() {
exit_thread.set();
thread.wait_to_finish();
for (int i = 0; i < connected_inputs.size(); i++) {
snd_rawmidi_t *midi_in = connected_inputs[i].rawmidi_ptr;
snd_rawmidi_close(midi_in);
}
connected_inputs.clear();
}
void MIDIDriverALSAMidi::lock() const {
mutex.lock();
}
void MIDIDriverALSAMidi::unlock() const {
mutex.unlock();
}
PoolStringArray MIDIDriverALSAMidi::get_connected_inputs() {
PoolStringArray list;
lock();
for (int i = 0; i < connected_inputs.size(); i++) {
snd_rawmidi_t *midi_in = connected_inputs[i].rawmidi_ptr;
snd_rawmidi_info_t *info;
snd_rawmidi_info_malloc(&info);
snd_rawmidi_info(midi_in, info);
list.push_back(snd_rawmidi_info_get_name(info));
snd_rawmidi_info_free(info);
}
unlock();
return list;
}
MIDIDriverALSAMidi::MIDIDriverALSAMidi() {
exit_thread.clear();
}
MIDIDriverALSAMidi::~MIDIDriverALSAMidi() {
close();
}
#endif // ALSAMIDI_ENABLED
|