Added a new MIDIDriver class

3 files changed, 278 insertions, 0 deletions

diff --git a/drivers/alsamidi/SCsub b/drivers/alsamidi/SCsub
new file mode 100644
index 0000000000..233593b0f9
--- /dev/null
+++ b/drivers/alsamidi/SCsub
@@ -0,0 +1,8 @@
+#!/usr/bin/env python
+
+Import('env')
+
+# Driver source files
+env.add_source_files(env.drivers_sources, "*.cpp")
+
+Export('env')
diff --git a/drivers/alsamidi/alsa_midi.cpp b/drivers/alsamidi/alsa_midi.cpp
new file mode 100644
index 0000000000..599470d7e0
--- /dev/null
+++ b/drivers/alsamidi/alsa_midi.cpp
@@ -0,0 +1,201 @@
+/*************************************************************************/
+/*  alsa_midi.cpp                                                        */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2018 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2018 Godot Engine contributors (cf. AUTHORS.md)    */
+/*                                                                       */
+/* 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 <errno.h>
+
+#include "alsa_midi.h"
+#include "os/os.h"
+#include "print_string.h"
+
+static int get_message_size(uint8_t message) {
+	switch (message & 0xF0) {
+		case 0x80: // note off
+		case 0x90: // note on
+		case 0xA0: // aftertouch
+		case 0xB0: // continuous controller
+			return 3;
+
+		case 0xC0: // patch change
+		case 0xD0: // channel pressure
+		case 0xE0: // pitch bend
+			return 2;
+	}
+
+	return 256;
+}
+
+void MIDIDriverALSAMidi::thread_func(void *p_udata) {
+	MIDIDriverALSAMidi *md = (MIDIDriverALSAMidi *)p_udata;
+	uint64_t timestamp = 0;
+	uint8_t buffer[256];
+	int expected_size = 255;
+	int bytes = 0;
+
+	while (!md->exit_thread) {
+		int ret;
+
+		md->lock();
+
+		for (int i = 0; i < md->connected_inputs.size(); i++) {
+			snd_rawmidi_t *midi_in = md->connected_inputs[i];
+			do {
+				uint8_t byte = 0;
+				ret = snd_rawmidi_read(midi_in, &byte, 1);
+				if (ret < 0) {
+					if (ret != -EAGAIN) {
+						ERR_PRINTS("snd_rawmidi_read error: " + String(snd_strerror(ret)));
+					}
+				} else {
+					if (byte & 0x80) {
+						// Flush previous packet if there is any
+						if (bytes) {
+							md->receive_input_packet(timestamp, buffer, bytes);
+							bytes = 0;
+						}
+						expected_size = get_message_size(byte);
+					}
+
+					if (bytes < 256) {
+						buffer[bytes++] = byte;
+						// If we know the size of the current packet receive it if it reached the expected size
+						if (bytes >= expected_size) {
+							md->receive_input_packet(timestamp, buffer, bytes);
+							bytes = 0;
+						}
+					}
+				}
+			} while (ret > 0);
+		}
+
+		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 != NULL; n++) {
+		char *name = snd_device_name_get_hint(*n, "NAME");
+
+		if (name != NULL) {
+			snd_rawmidi_t *midi_in;
+			int ret = snd_rawmidi_open(&midi_in, NULL, name, SND_RAWMIDI_NONBLOCK);
+			if (ret >= 0) {
+				connected_inputs.insert(i++, midi_in);
+			}
+		}
+
+		if (name != NULL)
+			free(name);
+	}
+	snd_device_name_free_hint(hints);
+
+	mutex = Mutex::create();
+	thread = Thread::create(MIDIDriverALSAMidi::thread_func, this);
+
+	return OK;
+}
+
+void MIDIDriverALSAMidi::close() {
+
+	if (thread) {
+		exit_thread = true;
+		Thread::wait_to_finish(thread);
+
+		memdelete(thread);
+		thread = NULL;
+	}
+
+	if (mutex) {
+		memdelete(mutex);
+		mutex = NULL;
+	}
+
+	for (int i = 0; i < connected_inputs.size(); i++) {
+		snd_rawmidi_t *midi_in = connected_inputs[i];
+		snd_rawmidi_close(midi_in);
+	}
+	connected_inputs.clear();
+}
+
+void MIDIDriverALSAMidi::lock() const {
+
+	if (mutex)
+		mutex->lock();
+}
+
+void MIDIDriverALSAMidi::unlock() const {
+
+	if (mutex)
+		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];
+		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() {
+
+	mutex = NULL;
+	thread = NULL;
+
+	exit_thread = false;
+}
+
+MIDIDriverALSAMidi::~MIDIDriverALSAMidi() {
+
+	close();
+}
+
+#endif
diff --git a/drivers/alsamidi/alsa_midi.h b/drivers/alsamidi/alsa_midi.h
new file mode 100644
index 0000000000..90e458a365
--- /dev/null
+++ b/drivers/alsamidi/alsa_midi.h
@@ -0,0 +1,69 @@
+/*************************************************************************/
+/*  alsa_midi.h                                                          */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2018 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2018 Godot Engine contributors (cf. AUTHORS.md)    */
+/*                                                                       */
+/* 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
+
+#ifndef ALSA_MIDI_H
+#define ALSA_MIDI_H
+
+#include <alsa/asoundlib.h>
+#include <stdio.h>
+
+#include "core/os/mutex.h"
+#include "core/os/thread.h"
+#include "core/vector.h"
+#include "os/midi_driver.h"
+
+class MIDIDriverALSAMidi : public MIDIDriver {
+
+	Thread *thread;
+	Mutex *mutex;
+
+	Vector<snd_rawmidi_t *> connected_inputs;
+
+	bool exit_thread;
+
+	static void thread_func(void *p_udata);
+
+	void lock() const;
+	void unlock() const;
+
+public:
+	virtual Error open();
+	virtual void close();
+
+	virtual PoolStringArray get_connected_inputs();
+
+	MIDIDriverALSAMidi();
+	virtual ~MIDIDriverALSAMidi();
+};
+
+#endif
+#endif