[alsa-devel] [PATCH v2 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 MIDI 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 | 44 +++++++++++++++++++++++++++++++++++++++-----
 2 files changed, 53 insertions(+), 5 deletions(-)

diff --git a/amidi/amidi.1 b/amidi/amidi.1
index 1b4cfb1ea956..391008177610 100644
--- a/amidi/amidi.1
+++ b/amidi/amidi.1
@@ -111,6 +111,12 @@ to stop receiving data.
 Does not ignore Active Sensing bytes (FEh) 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
@@ -121,6 +127,14 @@ 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 cedf18c5fd39..f726824723fb 100644
--- a/amidi/amidi.c
+++ b/amidi/amidi.c
@@ -48,6 +48,7 @@ static int receive_file;
 static int dump;
 static int timeout;
 static int stop;
+static int delay;
 static snd_rawmidi_t *input, **inputp;
 static snd_rawmidi_t *output, **outputp;
 
@@ -77,7 +78,8 @@ static void usage(void)
 		"-d, --dump             print received data as hexadecimal bytes\n"
 		"-t, --timeout=seconds  exits when no data has been received\n"
 		"                       for the specified duration\n"
-		"-a, --active-sensing   don't ignore active sensing bytes\n");
+		"-a, --active-sensing   don't ignore active sensing bytes\n"
+		"-D, --delay=mseconds   delay in between each SysEx message\n");
 }
 
 static void version(void)
@@ -406,7 +408,7 @@ 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:a";
+	static const char short_options[] = "hVlLp:s:r:S::dt:aD:";
 	static const struct option long_options[] = {
 		{"help", 0, NULL, 'h'},
 		{"version", 0, NULL, 'V'},
@@ -419,6 +421,7 @@ int main(int argc, char *argv[])
 		{"dump", 0, NULL, 'd'},
 		{"timeout", 1, NULL, 't'},
 		{"active-sensing", 0, NULL, 'a'},
+		{"delay", 1, NULL, 'D'},
 		{ }
 	};
 	int c, err, ok = 0;
@@ -463,6 +466,9 @@ int main(int argc, char *argv[])
 		case 'a':
 			ignore_active_sensing = 0;
 			break;
+		case 'D':
+			delay = atoi(optarg);
+			break;
 		default:
 			error("Try `amidi --help' for more information.");
 			return 1;
@@ -538,9 +544,37 @@ 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;
+
+			while (data < (send_data + send_data_length)) {
+				int len = 0;
+
+				if (data > send_data)
+					usleep(delay * 1000);
+
+				/* find beginning of SysEx and its end */
+				while((unsigned char)data[len] != 0xf0 &&
+				      (data + len) < (send_data + send_data_length))
+					len++;
+
+				while((unsigned char)data[len] != 0xf7 &&
+				      (data + len) < (send_data + send_data_length))
+					len++;
+				len++;
+
+				if ((err = snd_rawmidi_write(output, data, len)) < 0) {
+					error("cannot send data: %s", snd_strerror(err));
+					return err;
+				}
+
+				data += len;
+			}
 		}
 	}
 
-- 
2.9.2