Add support for FreeBSD raw usb-midi devices. Bits from Tobias

Kortkamp <t@tobik.me> plus configure script tweaks.

configure

@@ -20,6 +20,8 @@ Usage: configure [options]
 --disable-sun			disable sun audio backend
 --enable-rmidi			enable character device midi backend [$rmidi]
 --disable-rmidi			disable character device midi backend
+--enable-umidi			enable usb-midi backend [$umidi]
+--disable-umidi			disable usb-midi backend
 --with-libbsd			use the libbsd rather than bsd-compat/*
 --without-libbsd		don't use libbsd
 END
@@ -34,6 +36,7 @@ alsa=no					# do we want alsa support ?
 sun=no					# do we want sun support ?
 oss=no					# do we want oss support ?
 rmidi=no				# do we want support for raw char dev ?
+umidi=no				# do we want support for umidi ?
 precision=16				# aucat/sndiod arithmetic precision
 user=_sndio				# non-privileged user for sndio daemon
 libbsd=no				# use libbsd?
@@ -73,6 +76,7 @@ case `uname` in
 		-DHAVE_STRLCAT -DHAVE_STRLCPY -DHAVE_STRTONUM'
 		;;
 	DragonFly|FreeBSD)
+		umidi=yes
 		user=_sndio
 		so="$so libsndio.so"
 		defs='-DHAVE_ARC4RANDOM -DHAVE_ISSETUGID \\\
@@ -133,6 +137,12 @@ for i; do
 	--disable-rmidi)
 		rmidi=no
 		shift;;
+	--enable-umidi)
+		umidi=yes
+		shift;;
+	--disable-umidi)
+		umidi=no
+		shift;;
 	--privsep-user=*)
 		user="${i#--privsep-user=}"
 		shift;;
@@ -168,6 +178,13 @@ includedir="${includedir:-$prefix/include}"
 libdir="${libdir:-$prefix/lib}"
 mandir="${mandir:-$prefix/share/man}"
 
+#
+# umidi implies rmidi
+#
+if [ $umidi = yes ]; then
+	rmidi=yes
+fi
+
 #
 # if using ALSA, add corresponding parameters
 #
@@ -197,6 +214,13 @@ if [ $rmidi = yes ]; then
 	defs="$defs -DUSE_RMIDI"
 fi
 
+#
+# if using usb-midi raw devices for midi, add corresponding parameters
+#
+if [ $umidi = yes ]; then
+	defs="$defs -DUSE_UMIDI"
+fi
+
 #
 # if using libbsd, add corresponding parameters
 #
@@ -242,6 +266,7 @@ alsa..................... $alsa
 oss...................... $oss
 sun...................... $sun
 rmidi.................... $rmidi
+umidi.................... $umidi
 
 Do "make && make install" to compile and install sndio
 

libsndio/mio_rmidi.c

@@ -31,10 +31,19 @@
 #include "debug.h"
 #include "mio_priv.h"
 
+#ifdef USE_UMIDI
+#define DEVPATH_PREFIX	"/dev/umidi"
+#define DEVPATH_MAX 	(1 +		\
+	sizeof(DEVPATH_PREFIX) - 1 +	\
+	sizeof(int) * 3 +		\
+	1 +				\
+	sizeof(int) * 3)
+#else
 #define DEVPATH_PREFIX	"/dev/rmidi"
 #define DEVPATH_MAX 	(1 +		\
 	sizeof(DEVPATH_PREFIX) - 1 +	\
 	sizeof(int) * 3)
+#endif
 
 struct mio_rmidi_hdl {
 	struct mio_hdl mio;
@@ -63,6 +72,9 @@ mio_rmidi_getfd(const char *str, unsigned int mode, int nbio)
 	const char *p;
 	char path[DEVPATH_MAX];
 	unsigned int devnum;
+#ifdef USE_UMIDI
+	unsigned int subdevnum = 0;
+#endif
 	int fd, flags;
 
 	p = _sndio_parsetype(str, "rmidi");
@@ -79,11 +91,37 @@ mio_rmidi_getfd(const char *str, unsigned int mode, int nbio)
 		return -1;
 	}
 	p = _sndio_parsenum(p, &devnum, 255);
-	if (p == NULL || *p != '\0') {
+	if (p == NULL) {
 		DPRINTF("mio_rmidi_getfd: %s: number expected after '/'\n", str);
 		return -1;
 	}
+#ifdef USE_UMIDI
+	switch (*p) {
+	case '.':
+		p++;
+		p = _sndio_parsenum(p, &subdevnum, 255);
+		if (p == NULL) {
+			DPRINTF("mio_rmidi_getfd: %s: "
+				"number expected after '.'\n", str);
+			return -1;
+		}
+		break;
+	case '\0':
+		break;
+	default:
+		DPRINTF("mio_rmidi_getfd: %s: '.' expected\n", str);
+		return -1;
+	}
+#endif
+	if (*p != '\0') {
+		DPRINTF("mio_rmidi_getfd: junk at end of string: %s\n", p);
+		return -1;
+	}
+#ifdef USE_UMIDI
+	snprintf(path, sizeof(path), DEVPATH_PREFIX "%u.%u", devnum, subdevnum);
+#else
 	snprintf(path, sizeof(path), DEVPATH_PREFIX "%u", devnum);
+#endif
 	if (mode == (MIO_IN | MIO_OUT))
 		flags = O_RDWR;
 	else