Added mutex and proper audio playback

Author Mitja Felicijan <mitja.felicijan@gmail.com> 2024-10-09 17:59:41 +0200
Committer Mitja Felicijan <mitja.felicijan@gmail.com> 2024-10-09 17:59:41 +0200
Commit bfc79cef2cb743fedba3e93fd005d25b0a4923dc (patch)
-rw-r--r-- Makefile 2
-rw-r--r-- main.c 7
-rw-r--r-- midi.c 16
-rw-r--r-- midi.h 4
-rw-r--r-- mutex.c 19
-rw-r--r-- mutex.h 24
-rw-r--r-- soundfonts/general-808.sf2 bin 0 B -> 70.0 KB
-rw-r--r-- synth.c 31
-rw-r--r-- synth.h 4
9 files changed, 96 insertions, 11 deletions
diff --git a/Makefile b/Makefile
1 
CC      := cc
 1 
CC      := cc
2 
CFLAGS  := -Wall -Wextra -Wshadow -Wunused -Wswitch-enum -Wpedantic -ggdb
 2 
CFLAGS  := -Wall -Wextra -Wshadow -Wunused -Wswitch-enum -Wpedantic -ggdb
3 
LDFLAGS := -lm -ldl -lpthread -lasound
 3 
LDFLAGS := -lm -ldl -lpthread -lasound
4 
FILES   := main.c midi.c synth.c minisdl_audio.c
 4 
FILES   := main.c midi.c synth.c mutex.c minisdl_audio.c
5 
PROG    := ttdaw
 5 
PROG    := ttdaw
6 
  
 6 
  
7 
$(PROG): main.c
 7 
$(PROG): main.c
...
diff --git a/main.c b/main.c
...
7 
#include "version.h"
 7 
#include "version.h"
8 
#include "midi.h"
 8 
#include "midi.h"
9 
#include "synth.h"
 9 
#include "synth.h"
 
  
 10 
#include "mutex.h"
10 
  
 11 
  
11 
void help(const char *argv0) {
 12 
void help(const char *argv0) {
12 
	printf("Usage: %s [options]\n"
 13 
	printf("Usage: %s [options]\n"
...
70 
	fprintf(stdout, "> Device port:   %s\n", port_name);
 71 
	fprintf(stdout, "> Device port:   %s\n", port_name);
71 
	fprintf(stdout, "> Soundfont:     %s\n", soundfont_file);
 72 
	fprintf(stdout, "> Soundfont:     %s\n", soundfont_file);
72 
  
 73 
  
 
  
 74 
	// Create mutex.
 
  
 75 
	initialize_mutex();	
  
 76 
  
73 
	// Create synth thread.
 77 
	// Create synth thread.
74 
	pthread_t synth_thread;
 78 
	pthread_t synth_thread;
75 
	SynthArgs synth_args = { soundfont_file };
 79 
	SynthArgs synth_args = { soundfont_file };
...
90 
  
 94 
  
91 
	pthread_join(midi_thread, NULL);
 95 
	pthread_join(midi_thread, NULL);
92 
	pthread_join(synth_thread, NULL);
 96 
	pthread_join(synth_thread, NULL);
 
  
 97 
  
 
  
 98 
	// Destroy mutex.
 
  
 99 
	destroy_mutex();
93 
  
 100 
  
94 
	fprintf(stdout, "Exiting...\n");
 101 
	fprintf(stdout, "Exiting...\n");
95 
	return 0;
 102 
	return 0;
...
diff --git a/midi.c b/midi.c
...
5 
#include <alsa/asoundlib.h>
 5 
#include <alsa/asoundlib.h>
6 
  
 6 
  
7 
#include "midi.h"
 7 
#include "midi.h"
 
  
 8 
#include "mutex.h"
8 
  
 9 
  
9 
static snd_seq_t *seq_handle;
 10 
static snd_seq_t *seq_handle;
10 
static snd_seq_addr_t *ports;
 11 
static snd_seq_addr_t *ports;
...
81 
				}
 82 
				}
82 
  
 83 
  
83 
				if (ev) {
 84 
				if (ev) {
 
  
 85 
					pthread_mutex_lock(&mutex);
84 
					switch (ev->type) {
 86 
					switch (ev->type) {
85 
						case SND_SEQ_EVENT_NOTEON:
 87 
						case SND_SEQ_EVENT_NOTEON:
 
  
 88 
							shared_data.note = ev->data.note.note;
 
  
 89 
							shared_data.state = 1;
 
  
 90 
							shared_data.velocity = ev->data.note.velocity;
86 
							printf("%3d:%-3dNote on  %2d, note %d, velocity: %3d\n",
 91 
							printf("%3d:%-3dNote on  %2d, note %d, velocity: %3d\n",
87 
									ev->source.client, ev->source.port,
 92 
									ev->source.client, ev->source.port,
88 
									ev->data.note.channel,
 93 
									ev->data.note.channel,
...
91 
							break;
 96 
							break;
92 
  
 97 
  
93 
						case SND_SEQ_EVENT_NOTEOFF:
 98 
						case SND_SEQ_EVENT_NOTEOFF:
 
  
 99 
							shared_data.note = ev->data.note.note;
 
  
 100 
							shared_data.state = 0;
 
  
 101 
							shared_data.velocity = 0;
94 
							printf("%3d:%-3dNote off\t%2d, note %d\n",
 102 
							printf("%3d:%-3dNote off\t%2d, note %d\n",
95 
									ev->source.client, ev->source.port,
 103 
									ev->source.client, ev->source.port,
96 
									ev->data.note.channel,
 104 
									ev->data.note.channel,
97 
									ev->data.note.note);
 105 
									ev->data.note.note);
98 
							break;
 106 
							break;
 
  
 107 
						default:
 
  
 108 
							break;
 
  
 109 
					}
99 
  
 110 
  
 
  
 111 
					shared_data.action = 1;
 
  
 112 
					shared_data.preset = 3;
100 
  
 113 
  
101 
					}
 114 
					pthread_cond_signal(&cond_synth);
 
  
 115 
					pthread_mutex_unlock(&mutex);
102 
				}
 116 
				}
103 
			}
 117 
			}
104 
  
 118 
  
...
diff --git a/midi.h b/midi.h
1 
#include <alsa/asoundlib.h>
 
  
2 
  
 
  
3 
#ifndef MIDI_H_
 1 
#ifndef MIDI_H_
4 
#define MIDI_H_
 2 
#define MIDI_H_
 
  
 3 
  
 
  
 4 
#include <alsa/asoundlib.h>
5 
  
 5 
  
6 
#define CLIENT_NAME "ttdaw"
 6 
#define CLIENT_NAME "ttdaw"
7 
#define MAX_MIDI_PORTS 1
 7 
#define MAX_MIDI_PORTS 1
...
diff --git a/mutex.c b/mutex.c 
  
 1 
#include <pthread.h>
 
  
 2 
#include "mutex.h"
 
  
 3 
  
 
  
 4 
SharedData shared_data;
 
  
 5 
  
 
  
 6 
pthread_mutex_t mutex;
 
  
 7 
pthread_cond_t cond_midi;
 
  
 8 
pthread_cond_t cond_synth;
 
  
 9 
  
 
  
 10 
void initialize_mutex() {
 
  
 11 
	pthread_mutex_init(&mutex, NULL);
 
  
 12 
	pthread_cond_init(&cond_synth, NULL);
 
  
 13 
}
 
  
 14 
  
 
  
 15 
void destroy_mutex() {
 
  
 16 
	pthread_mutex_destroy(&mutex);
 
  
 17 
	pthread_cond_destroy(&cond_synth);
 
  
 18 
}
 
  
 19 
  
diff --git a/mutex.h b/mutex.h 
  
 1 
#ifndef MUTEX_H
 
  
 2 
#define MUTEX_H
 
  
 3 
  
 
  
 4 
#include <pthread.h>
 
  
 5 
  
 
  
 6 
typedef struct {
 
  
 7 
	int note;
 
  
 8 
	int state;
 
  
 9 
	int velocity;
 
  
 10 
	int preset;
 
  
 11 
	int action;
 
  
 12 
} SharedData;
 
  
 13 
  
 
  
 14 
extern SharedData shared_data;
 
  
 15 
  
 
  
 16 
extern pthread_mutex_t mutex;
 
  
 17 
extern pthread_cond_t cond_midi;
 
  
 18 
extern pthread_cond_t cond_synth;
 
  
 19 
  
 
  
 20 
void initialize_mutex();
 
  
 21 
void destroy_mutex();
 
  
 22 
  
 
  
 23 
#endif // MUTEX_H
 
  
 24 
  
diff --git a/soundfonts/general-808.sf2 b/soundfonts/general-808.sf2
diff --git a/synth.c b/synth.c
...
2 
#include <unistd.h>
 2 
#include <unistd.h>
3 
  
 3 
  
4 
#include "synth.h"
 4 
#include "synth.h"
 
  
 5 
#include "mutex.h"
5 
#include "minisdl_audio.h"
 6 
#include "minisdl_audio.h"
6 
  
 7 
  
7 
#define TSF_IMPLEMENTATION
 8 
#define TSF_IMPLEMENTATION
...
12 
  
 13 
  
13 
// Render the audio samples in float format.
 14 
// Render the audio samples in float format.
14 
static void AudioCallback(void* data, Uint8 *stream, int len) {
 15 
static void AudioCallback(void* data, Uint8 *stream, int len) {
15 
	int SampleCount = (len / (2 * sizeof(float))); // 2 output channels.
 16 
	int SampleCount = (len / (AUDIO_CHANNELS * sizeof(float))); // 2 output channels.
16 
	SDL_LockMutex(g_Mutex); // Get exclusive lock.
 17 
	SDL_LockMutex(g_Mutex); // Get exclusive lock.
17 
	tsf_render_float(g_TinySoundFont, (float*)stream, SampleCount, 0);
 18 
	tsf_render_float(g_TinySoundFont, (float*)stream, SampleCount, 0);
18 
	SDL_UnlockMutex(g_Mutex);
 19 
	SDL_UnlockMutex(g_Mutex);
...
22 
	SynthArgs* args = (SynthArgs*)arg;
 23 
	SynthArgs* args = (SynthArgs*)arg;
23 
  
 24 
  
24 
	SDL_AudioSpec OutputAudioSpec;
 25 
	SDL_AudioSpec OutputAudioSpec;
25 
	OutputAudioSpec.freq = 44100;
 26 
	OutputAudioSpec.freq = AUDIO_FREQ;
26 
	OutputAudioSpec.format = AUDIO_F32;
 27 
	OutputAudioSpec.format = AUDIO_F32;
27 
	OutputAudioSpec.channels = 2;
 28 
	OutputAudioSpec.channels = AUDIO_CHANNELS;
28 
	OutputAudioSpec.samples = 4096;
 29 
	OutputAudioSpec.samples = AUDIO_SAMPLES;
29 
	OutputAudioSpec.callback = AudioCallback;
 30 
	OutputAudioSpec.callback = AudioCallback;
30 
  
 31 
  
31 
	// Initialize the audio system.
 32 
	// Initialize the audio system.
...
56 
	SDL_PauseAudio(0);
 57 
	SDL_PauseAudio(0);
57 
  
 58 
  
58 
	while (1) {
 59 
	while (1) {
59 
		sleep(1);
 60 
		pthread_mutex_lock(&mutex);
 
  
 61 
		while (shared_data.action == 0) {
 
  
 62 
			pthread_cond_wait(&cond_synth, &mutex);
 
  
 63 
		}
60 
  
 64 
  
61 
		SDL_LockMutex(g_Mutex);
 65 
		SDL_LockMutex(g_Mutex);
62 
		tsf_note_off(g_TinySoundFont, 1, 50);
 66 
  
63 
		tsf_note_on(g_TinySoundFont, 1, 50, 1.0f);
 67 
		if (shared_data.state == 0) {
 
  
 68 
			tsf_note_off(g_TinySoundFont, shared_data.preset, shared_data.note);
 
  
 69 
		} else {
 
  
 70 
			float normalized_velocity = (float)shared_data.velocity / 127.0f;
 
  
 71 
			tsf_note_on(g_TinySoundFont, shared_data.preset, shared_data.note, normalized_velocity);
 
  
 72 
		}
 
  
 73 
  
64 
		SDL_UnlockMutex(g_Mutex);
 74 
		SDL_UnlockMutex(g_Mutex);
 
  
 75 
  
 
  
 76 
		printf("Consumed: note=%d, state=%d velocity:%d\n", shared_data.note, shared_data.state, shared_data.velocity);
 
  
 77 
  
 
  
 78 
		// Reset state to indicate data has been consumed.
 
  
 79 
		shared_data.action = 0; 
  
 80 
  
 
  
 81 
		pthread_mutex_unlock(&mutex);
65 
	}
 82 
	}
66 
}
 83 
}
67 
  
 84 
  
diff --git a/synth.h b/synth.h
1 
#ifndef SYNTH_H_
 1 
#ifndef SYNTH_H_
2 
#define SYNTH_H_
 2 
#define SYNTH_H_
3 
  
 3 
  
 
  
 4 
#define AUDIO_FREQ 44100
 
  
 5 
#define AUDIO_SAMPLES 64
 
  
 6 
#define AUDIO_CHANNELS 2
 
  
 7 
  
4 
typedef struct {
 8 
typedef struct {
5 
	char *soundfont_file;
 9 
	char *soundfont_file;
6 
} SynthArgs;
 10 
} SynthArgs;
...