From f5a8148993bd76c9c7a2d70dc79845509871d2cd Mon Sep 17 00:00:00 2001
From: Neale Pickett <neale@woozle.org>
Date: Sun, 14 Dec 2014 21:26:01 -0700
Subject: [PATCH] Seems to work with MP3e2 again

---
 alsa.c | 36 +++++++++++++++++++++++++++---------
 dump.h |  2 +-
 usb.c  | 13 ++++---------
 3 files changed, 32 insertions(+), 19 deletions(-)

diff --git a/alsa.c b/alsa.c
index 87d13ff..6765b66 100644
--- a/alsa.c
+++ b/alsa.c
@@ -73,9 +73,10 @@ alsa_fd_setup(int *nfds, fd_set *rfds, fd_set *wfds)
 void
 alsa_read_ready()
 {
-	static snd_seq_event_t *ev;
-
+	snd_midi_event_init(midi_event_parser);
+	
 	for (;;) {
+		snd_seq_event_t *ev;
 		unsigned char buf[ALSA_BUFSIZE];
 		long converted;
 		int r;
@@ -83,19 +84,34 @@ alsa_read_ready()
 		r = snd_seq_event_input(snd_handle, &ev);
 		
 		if (r == -EAGAIN) {
+			// input queue empty
 			break;
-		}
-		if (r == -ENOSPC) {
-			warn("Out of space on input queue");
+		} else if (r == -ENOSPC) {
+			warn("Input queue overflow");
+			continue;
+		} else if (r < 0) {
+			warn("snd_seq_event_input() = %d", r);
+			continue;
 		}
 
 		converted = snd_midi_event_decode(midi_event_parser, buf, ALSA_BUFSIZE, ev);
 		if (converted < 0) {
-			warn("Can't decode MIDI event type %d", ev->type);
-		} else {
-			DUMP_d(converted);
-			usb_write(buf, converted);
+			warn("Can't decode MIDI event type %x", ev->type);
+			continue;
 		}
+		
+		if (converted < 3) {
+			int i;
+			
+			warn("Uh oh, weird MIDI packet with length %ld (does this make sense if prefixed with 90?)", converted);
+			
+			for (i = 0; i < converted; i += 1) {
+				fprintf(stderr, "  %02x", buf[i]);
+			}
+			fprintf(stderr, "\n");
+		}
+		
+		usb_write(buf, converted);
 	}
 }
 
@@ -119,6 +135,8 @@ alsa_write(uint8_t *data, size_t datalen)
 {
 	size_t offset = 0;
 	
+	snd_midi_event_init(midi_event_parser);
+	
 	for (; datalen > offset;) {
 		snd_seq_event_t ev;
 		long encoded;
diff --git a/dump.h b/dump.h
index 9d002c8..1fb863b 100644
--- a/dump.h
+++ b/dump.h
@@ -9,7 +9,7 @@
 #ifdef NODUMP
 #  define DUMPf(fmt, args...)
 #else
-#  define DUMPf(fmt, args...) fprintf(stderr, "%s:%s:%d " fmt "\n", __FILE__, __FUNCTION__, __LINE__, ##args)
+#  define DUMPf(fmt, args...) fprintf(stderr, "%s:%d " fmt "\n", __FILE__,  __LINE__, ##args)
 #endif
 #define DUMP() DUMPf("")
 #define DUMP_d(v) DUMPf("%s = %d", #v, (int)v)
diff --git a/usb.c b/usb.c
index 70b5206..fb3951b 100644
--- a/usb.c
+++ b/usb.c
@@ -156,7 +156,9 @@ usb_check_fds(fd_set *rfds, fd_set *wfds)
 void
 usb_write_done(struct libusb_transfer *xfer)
 {
-	DUMP_d(xfer->status);
+	if (xfer->status) {
+		warn("USB Write status %d", xfer->status);
+	}
 	writes_pending -= 1;
 	free(xfer->buffer);
 	libusb_free_transfer(xfer);
@@ -167,14 +169,7 @@ usb_write(uint8_t *data, size_t datalen)
 {
 	struct libusb_transfer *xfer;
 	unsigned char *buf;
-	int i;
-	
-	DUMP_d(datalen);
-	for (i = 0; i < datalen; i += 1) {
-		fprintf(stderr, "  %02x", data[i]);
-	}
-	fprintf(stderr, "\n");
-	
+		
 	writes_pending += 1;
 	xfer = libusb_alloc_transfer(0);
 	buf = (unsigned char *)malloc(datalen);