Add clock

2 files changed, 63 insertions, 17 deletions

diff --git a/MIDIPlayer.cpp b/MIDIPlayer.cpp
index 8202850..061b8f6 100644
--- a/MIDIPlayer.cpp
+++ b/MIDIPlayer.cpp
@@ -11,6 +11,7 @@
 #include <string>
 #include <thread>
 #include <unordered_set>
+#include <stdexcept>
 
 namespace bp = boost::process;
 namespace fs = std::filesystem;
@@ -43,7 +44,10 @@ void MIDIPlayer::start()
   if (m_child.valid() && m_child.running()) {
     stop();
   } else {
-    m_child = bp::child(fmt::format("aplaymidi -p{} \"{}\"", m_client, m_file).c_str());//, bp::std_out > bp::null);
+    m_child = bp::child(fmt::format("/home/ernie/code/midiplay/aplaymidi-mp -c -p{} \"{}\"", m_client, m_file).c_str());//, bp::std_out > bp::null);
+    if (!m_child.valid() || !m_child.running()) {
+      throw std::runtime_error("aplaymidi not started");
+    }
   }
 }
 
diff --git a/aplaymidi-mp.c b/aplaymidi-mp.c
index 8ad9630..0599f2a 100644
--- a/aplaymidi-mp.c
+++ b/aplaymidi-mp.c
@@ -77,7 +77,8 @@ static int num_tracks;
 static struct track *tracks;
 static int smpte_timing;
 static int ump_mode;
-static int add_clock;
+static int clock_mode;
+static int time_division;
 
 /* prints an error message to stderr */
 static void errormsg(const char *msg, ...)
@@ -298,6 +299,20 @@ static void skip(int bytes)
 		read_byte(), --bytes;
 }
 
+static void add_clock(struct track *track, int tick_step, int track_end)
+{
+	int tick = 0;
+	struct event *event;
+
+	while (tick <= track_end) {
+		event = new_event(track, 0);
+		event->type = SND_SEQ_EVENT_CLOCK;
+		event->port = 0;
+		event->tick = tick;
+		tick += tick_step;
+	}
+}
+
 /* reads one complete track from the file */
 static int read_track(struct track *track, int track_end)
 {
@@ -454,10 +469,10 @@ _error:
 /* reads an entire MIDI file */
 static int read_smf(void)
 {
-	int header_len, type, time_division, i, err;
+	int header_len, type, i, err;
 	snd_seq_queue_tempo_t *queue_tempo;
 
-	/* the curren position is immediately after the "MThd" id */
+	/* the current position is immediately after the "MThd" id */
 	header_len = read_int(4);
 	if (header_len < 6) {
 invalid_format:
@@ -504,19 +519,23 @@ invalid_format:
 		switch (i) {
 		case 24:
 			snd_seq_queue_tempo_set_tempo(queue_tempo, 500000);
-			snd_seq_queue_tempo_set_ppq(queue_tempo, 12 * time_division);
+			time_division *= 12;
+			snd_seq_queue_tempo_set_ppq(queue_tempo, time_division);
 			break;
 		case 25:
 			snd_seq_queue_tempo_set_tempo(queue_tempo, 400000);
-			snd_seq_queue_tempo_set_ppq(queue_tempo, 10 * time_division);
+			time_division *= 10;
+			snd_seq_queue_tempo_set_ppq(queue_tempo, time_division);
 			break;
 		case 29: /* 30 drop-frame */
 			snd_seq_queue_tempo_set_tempo(queue_tempo, 100000000);
-			snd_seq_queue_tempo_set_ppq(queue_tempo, 2997 * time_division);
+			time_division *= 2997;
+			snd_seq_queue_tempo_set_ppq(queue_tempo, time_division);
 			break;
 		case 30:
 			snd_seq_queue_tempo_set_tempo(queue_tempo, 500000);
-			snd_seq_queue_tempo_set_ppq(queue_tempo, 15 * time_division);
+			time_division *= 15;
+			snd_seq_queue_tempo_set_ppq(queue_tempo, time_division);
 			break;
 		default:
 			errormsg("%s: invalid number of SMPTE frames per second (%d)",
@@ -676,6 +695,11 @@ static int fill_legacy_event(struct event* event, snd_seq_event_t *ev)
 		snd_seq_ev_set_variable(ev, event->data.length, event->sysex);
 		handle_big_sysex(ev);
 		break;
+	case SND_SEQ_EVENT_CLOCK:
+		snd_seq_ev_set_fixed(ev);
+		ev->data.control.channel = event->data.d[0];
+		ev->data.control.value = event->data.d[1];
+		break;
 	default:
 		fatal("Invalid event type %d!", ev->type);
 	}
@@ -759,19 +783,26 @@ static int fill_ump_event(struct event* event, snd_seq_ump_event_t *ump_ev,
 	return 0;
 }
 
-static void play_midi(void)
+static int get_max_tick(void)
 {
-	snd_seq_ump_event_t ump_ev;
-	snd_seq_event_t ev;
-	int i, max_tick, err;
-
 	/* calculate length of the entire file */
-	max_tick = -1;
+	int i, max_tick = -1;
 	for (i = 0; i < num_tracks; ++i) {
 		if (tracks[i].end_tick > max_tick)
 			max_tick = tracks[i].end_tick;
 	}
 
+	return max_tick;
+}
+
+static void play_midi(void)
+{
+	snd_seq_ump_event_t ump_ev;
+	snd_seq_event_t ev;
+	int i, max_tick, err;
+
+	max_tick = get_max_tick();
+
 	/* initialize current position in each track */
 	for (i = 0; i < num_tracks; ++i)
 		tracks[i].current_event = tracks[i].first_event;
@@ -900,8 +931,19 @@ static void play_file(void)
 	if (file != stdin)
 		fclose(file);
 
-	if (ok)
+	if (ok) {
+		if (clock_mode) {
+			num_tracks += 1;
+			tracks = realloc(tracks, num_tracks * sizeof(struct track));
+			if (!tracks) {
+				errormsg("out of memory");
+				return;
+			}
+			memset(&tracks[num_tracks - 1], 0, sizeof(struct track));
+			add_clock(&tracks[num_tracks - 1], time_division / 24, get_max_tick());
+		}
 		play_midi();
+	}
 
 	cleanup_file_data();
 }
@@ -960,7 +1002,7 @@ static void version(void)
 	puts("aplaymidi version " SND_UTIL_VERSION_STR);
 }
 
-#define OPTIONS	"hVlp:d:u:"
+#define OPTIONS	"hVlcp:d:u:"
 
 int main(int argc, char *argv[])
 {
@@ -1004,7 +1046,7 @@ int main(int argc, char *argv[])
 				fatal("Only MIDI 1.0 is supported");
 			break;
 		case 'c':
-                        add_clock = 1;
+                        clock_mode = 1;
 			break;
 		default:
 			usage(argv[0]);