[alsa-devel] [PATCH v6 1/2] amidi: add delay option

[Felipe F. Tonello]

This patch adds a new options to amidi tool to add a delay (in milliseconds)
to each SysEx message.

This is very useful when sending firmware updates to a remote device via SysEx
or any other use that requires this delay in between messages.

Signed-off-by: Felipe F. Tonello <eu at felipetonello.com>
---
 amidi/amidi.1 | 14 ++++++++++++++
 amidi/amidi.c | 58 +++++++++++++++++++++++++++++++++++++++++++++++++++++-----
 2 files changed, 67 insertions(+), 5 deletions(-)

diff --git a/amidi/amidi.1 b/amidi/amidi.1
index 86beb27a1e3b..4ca2164788f1 100644
--- a/amidi/amidi.1
+++ b/amidi/amidi.1
@@ -120,6 +120,12 @@ received MIDI commands.
 Does not ignore Clock bytes (F8h) when saving or printing received
 MIDI commands.
 
+.TP
+.I \-D, \-\-delay=mseconds
+Adds a delay in between each SysEx message sent to a device. It is
+useful when sending firmware updates via SysEx messages to a remote
+device.
+
 .SH EXAMPLES
 
 .TP
@@ -130,6 +136,14 @@ to port
 .I hw:0.
 
 .TP
+.B amidi \-p hw:1,0,0 -s firmware.syx \-D 100
+will send the MIDI commands in
+.I firmware.syx
+to port
+.I hw:1,0,0
+with 100 milliseconds delay in between each SysEx message.
+
+.TP
 .B amidi \-S 'F0 43 10 4C 00 00 7E 00 F7'
 sends an XG Reset to the default port.
 
diff --git a/amidi/amidi.c b/amidi/amidi.c
index c20512cc96a7..d0dbb322f80a 100644
--- a/amidi/amidi.c
+++ b/amidi/amidi.c
@@ -52,6 +52,7 @@ static int receive_file;
 static int dump;
 static float timeout;
 static int stop;
+static int delay;
 static snd_rawmidi_t *input, **inputp;
 static snd_rawmidi_t *output, **outputp;
 
@@ -82,7 +83,8 @@ static void usage(void)
 		"-t, --timeout=seconds  exits when no data has been received\n"
 		"                       for the specified duration\n"
 		"-a, --active-sensing   include active sensing bytes\n"
-		"-c, --clock            include clock bytes\n");
+		"-c, --clock            include clock bytes\n"
+		"-D, --delay=mseconds   delay in between each SysEx message\n");
 }
 
 static void version(void)
@@ -411,7 +413,7 @@ static void add_send_hex_data(const char *str)
 
 int main(int argc, char *argv[])
 {
-	static const char short_options[] = "hVlLp:s:r:S::dt:ac";
+	static const char short_options[] = "hVlLp:s:r:S::dt:acD:";
 	static const struct option long_options[] = {
 		{"help", 0, NULL, 'h'},
 		{"version", 0, NULL, 'V'},
@@ -425,6 +427,7 @@ int main(int argc, char *argv[])
 		{"timeout", 1, NULL, 't'},
 		{"active-sensing", 0, NULL, 'a'},
 		{"clock", 0, NULL, 'c'},
+		{"delay", 1, NULL, 'D'},
 		{ }
 	};
 	int c, err, ok = 0;
@@ -474,6 +477,9 @@ int main(int argc, char *argv[])
 		case 'c':
 			ignore_clock = 0;
 			break;
+		case 'D':
+			delay = atoi(optarg);
+			break;
 		default:
 			error("Try `amidi --help' for more information.");
 			return 1;
@@ -549,9 +555,51 @@ int main(int argc, char *argv[])
 			error("cannot set blocking mode: %s", snd_strerror(err));
 			goto _exit;
 		}
-		if ((err = snd_rawmidi_write(output, send_data, send_data_length)) < 0) {
-			error("cannot send data: %s", snd_strerror(err));
-			goto _exit;
+		if (!delay) {
+			if ((err = snd_rawmidi_write(output, send_data, send_data_length)) < 0) {
+				error("cannot send data: %s", snd_strerror(err));
+				return err;
+			}
+		} else {
+			char *data = send_data;
+			size_t buffer_size;
+			snd_rawmidi_params_t *param;
+			snd_rawmidi_status_t *st;
+
+			snd_rawmidi_status_malloc(&st);
+
+			snd_rawmidi_params_malloc(&param);
+			snd_rawmidi_params_current(output, param);
+			buffer_size = snd_rawmidi_params_get_buffer_size(param);
+			snd_rawmidi_params_free(param);
+
+			while (data < (send_data + send_data_length)) {
+				int len = send_data + send_data_length - data;
+				char *temp;
+
+				if (data > send_data) {
+					snd_rawmidi_status(output, st);
+					do {
+						/* 320 µs per byte as noted in Page 1 of MIDI spec */
+						usleep((buffer_size - snd_rawmidi_status_get_avail(st)) * 320);
+						snd_rawmidi_status(output, st);
+					} while(snd_rawmidi_status_get_avail(st) < buffer_size);
+					usleep(delay * 1000);
+				}
+
+				/* find end of SysEx */
+				if ((temp = memchr(data, 0xf7, len)) != NULL)
+					len = temp - data + 1;
+
+				if ((err = snd_rawmidi_write(output, data, len)) < 0) {
+					error("cannot send data: %s", snd_strerror(err));
+					return err;
+				}
+
+				data += len;
+			}
+
+			snd_rawmidi_status_free(st);
 		}
 	}
 
-- 
2.9.3