AUDIO: Add pure virtual MidiDriver::isOpen() method

This in turn enables modifying MidiDriver_MPU401::close() to allow
it to be called on a midi driver that has not yet been opened.

The specific issue that triggered me to make these changes was a
crash-upon-quit in HUGO, caused by it instantiating a midi driver,
then encountering an error (missing hugo.dat) *before* having
opened the new midi driver; the general cleanup code then tries
to close the (not yet opened) midi driver -> kaboom

Also fixed some engines which were leaking MidiDriver instances.

9 files changed, 71 insertions, 54 deletions

diff --git a/backends/midi/alsa.cpp b/backends/midi/alsa.cpp
index feed60eaef..2257f60e27 100644
--- a/backends/midi/alsa.cpp
+++ b/backends/midi/alsa.cpp
@@ -71,6 +71,7 @@ class MidiDriver_ALSA : public MidiDriver_MPU401 {
 public:
 	MidiDriver_ALSA(int client, int port);
 	int open();
+	bool isOpen() const { return _isOpen; }
 	void close();
 	void send(uint32 b);
 	void sysEx(const byte *msg, uint16 length);
diff --git a/backends/midi/camd.cpp b/backends/midi/camd.cpp
index 57251b45e1..ee3baaadd2 100644
--- a/backends/midi/camd.cpp
+++ b/backends/midi/camd.cpp
@@ -46,6 +46,7 @@ class MidiDriver_CAMD : public MidiDriver_MPU401 {
 public:
 	MidiDriver_CAMD();
 	int open();
+	bool isOpen() const { return _isOpen; }
 	void close();
 	void send(uint32 b);
 	void sysEx(const byte *msg, uint16 length);
diff --git a/backends/midi/coreaudio.cpp b/backends/midi/coreaudio.cpp
index 75c512cad7..0158cc4a1d 100644
--- a/backends/midi/coreaudio.cpp
+++ b/backends/midi/coreaudio.cpp
@@ -72,7 +72,9 @@ do {                                                                \
 class MidiDriver_CORE : public MidiDriver_MPU401 {
 public:
 	MidiDriver_CORE();
+	~MidiDriver_CORE();
 	int open();
+	bool isOpen() const { return _auGraph != 0; }
 	void close();
 	void send(uint32 b);
 	void sysEx(const byte *msg, uint16 length);
@@ -86,10 +88,18 @@ MidiDriver_CORE::MidiDriver_CORE()
 	: _auGraph(0) {
 }
 
+MidiDriver_CORE::~MidiDriver_CORE() {
+	if (_auGraph) {
+		AUGraphStop(_auGraph);
+		DisposeAUGraph(_auGraph);
+		_auGraph = 0;
+	}
+}
+
 int MidiDriver_CORE::open() {
 	OSStatus err = 0;
 
-	if (_auGraph)
+	if (isOpen())
 		return MERR_ALREADY_OPEN;
 
 	// Open the Music Device.
@@ -176,7 +186,6 @@ bail:
 
 void MidiDriver_CORE::close() {
 	MidiDriver_MPU401::close();
-
 	if (_auGraph) {
 		AUGraphStop(_auGraph);
 		DisposeAUGraph(_auGraph);
@@ -185,7 +194,7 @@ void MidiDriver_CORE::close() {
 }
 
 void MidiDriver_CORE::send(uint32 b) {
-	assert(_auGraph != NULL);
+	assert(isOpen());
 
 	byte status_byte = (b & 0x000000FF);
 	byte first_byte = (b & 0x0000FF00) >> 8;
@@ -198,7 +207,7 @@ void MidiDriver_CORE::sysEx(const byte *msg, uint16 length) {
 	unsigned char buf[266];
 
 	assert(length + 2 <= ARRAYSIZE(buf));
-	assert(_auGraph != NULL);
+	assert(isOpen());
 
 	// Add SysEx frame
 	buf[0] = 0xF0;
diff --git a/backends/midi/coremidi.cpp b/backends/midi/coremidi.cpp
index c0663352cb..9123c9bc8c 100644
--- a/backends/midi/coremidi.cpp
+++ b/backends/midi/coremidi.cpp
@@ -56,6 +56,7 @@ public:
 	MidiDriver_CoreMIDI();
 	~MidiDriver_CoreMIDI();
 	int open();
+	bool isOpen() const { return mOutPort != 0 && mDest != 0; }
 	void close();
 	void send(uint32 b);
 	void sysEx(const byte *msg, uint16 length);
@@ -80,7 +81,7 @@ MidiDriver_CoreMIDI::~MidiDriver_CoreMIDI() {
 }
 
 int MidiDriver_CoreMIDI::open() {
-	if (mDest)
+	if (isOpen())
 		return MERR_ALREADY_OPEN;
 
 	OSStatus err = noErr;
@@ -106,7 +107,7 @@ int MidiDriver_CoreMIDI::open() {
 void MidiDriver_CoreMIDI::close() {
 	MidiDriver_MPU401::close();
 
-	if (mOutPort && mDest) {
+	if (isOpen()) {
 		MIDIPortDispose(mOutPort);
 		mOutPort = 0;
 		mDest = 0;
@@ -114,8 +115,7 @@ void MidiDriver_CoreMIDI::close() {
 }
 
 void MidiDriver_CoreMIDI::send(uint32 b) {
-	assert(mOutPort != 0);
-	assert(mDest != 0);
+	assert(isOpen());
 
 	// Extract the MIDI data
 	byte status_byte = (b & 0x000000FF);
@@ -158,8 +158,7 @@ void MidiDriver_CoreMIDI::send(uint32 b) {
 }
 
 void MidiDriver_CoreMIDI::sysEx(const byte *msg, uint16 length) {
-	assert(mOutPort != 0);
-	assert(mDest != 0);
+	assert(isOpen());
 
 	byte buf[384];
 	MIDIPacketList *packetList = (MIDIPacketList *)buf;
diff --git a/backends/midi/dmedia.cpp b/backends/midi/dmedia.cpp
index f0ab84c934..c4c1968354 100644
--- a/backends/midi/dmedia.cpp
+++ b/backends/midi/dmedia.cpp
@@ -57,6 +57,7 @@ class MidiDriver_DMEDIA : public MidiDriver_MPU401 {
 public:
 	MidiDriver_DMEDIA();
 	int open();
+	bool isOpen() const { return _isOpen; }
 	void close();
 	void send(uint32 b);
 	void sysEx(const byte *msg, uint16 length);
@@ -179,7 +180,7 @@ void MidiDriver_DMEDIA::sysEx (const byte *msg, uint16 length) {
 	memcpy(buf, msg, length);
 	buf[length] = MD_EOX;
 	event.sysexmsg = buf;
-        event.msglen = length;
+	event.msglen = length;
 	event.msg[0] = MD_SYSEX;
 	event.msg[1] = 0;
 	event.msg[2] = 0;
diff --git a/backends/midi/seq.cpp b/backends/midi/seq.cpp
index 064129b74a..7cd7f0a38e 100644
--- a/backends/midi/seq.cpp
+++ b/backends/midi/seq.cpp
@@ -55,6 +55,7 @@ class MidiDriver_SEQ : public MidiDriver_MPU401 {
 public:
 	MidiDriver_SEQ();
 	int open();
+	bool isOpen() const { return _isOpen; }
 	void close();
 	void send(uint32 b);
 	void sysEx(const byte *msg, uint16 length);
diff --git a/backends/midi/stmidi.cpp b/backends/midi/stmidi.cpp
index 562c3c7ece..42f829a7a3 100644
--- a/backends/midi/stmidi.cpp
+++ b/backends/midi/stmidi.cpp
@@ -48,8 +48,9 @@
 
 class MidiDriver_STMIDI : public MidiDriver_MPU401 {
 public:
-        MidiDriver_STMIDI() : _isOpen (false) { }
+	MidiDriver_STMIDI() : _isOpen (false) { }
 	int open();
+	bool isOpen() const { return _isOpen; }
 	void close();
 	void send(uint32 b);
 	void sysEx(const byte *msg, uint16 length);
@@ -59,7 +60,7 @@ private:
 };
 
 int MidiDriver_STMIDI::open() {
-	if ((_isOpen) && (!Bcostat(4)))
+	if (_isOpen && (!Bcostat(4)))
 		return MERR_ALREADY_OPEN;
 	warning("ST Midi Port Open");
 	_isOpen = true;
@@ -123,36 +124,36 @@ void MidiDriver_STMIDI::sysEx (const byte *msg, uint16 length) {
 
 class StMidiMusicPlugin : public MusicPluginObject {
 public:
-        const char *getName() const {
-                return "STMIDI";
-        }
+	const char *getName() const {
+		return "STMIDI";
+	}
 
-        const char *getId() const {
-                return "stmidi";
-        }
+	const char *getId() const {
+		return "stmidi";
+	}
 
-        MusicDevices getDevices() const;
-		Common::Error createInstance(MidiDriver **mididriver, MidiDriver::DeviceHandle = 0) const;
+	MusicDevices getDevices() const;
+	Common::Error createInstance(MidiDriver **mididriver, MidiDriver::DeviceHandle = 0) const;
 };
 
 MusicDevices StMidiMusicPlugin::getDevices() const {
-        MusicDevices devices;
-        // TODO: Return a different music type depending on the configuration
-        // TODO: List the available devices
-        devices.push_back(MusicDevice(this, "", MT_GM));
-        return devices;
+	MusicDevices devices;
+	// TODO: Return a different music type depending on the configuration
+	// TODO: List the available devices
+	devices.push_back(MusicDevice(this, "", MT_GM));
+	return devices;
 }
 
 Common::Error StMidiMusicPlugin::createInstance(MidiDriver **mididriver, MidiDriver::DeviceHandle) const {
-        *mididriver = new MidiDriver_STMIDI();
+	*mididriver = new MidiDriver_STMIDI();
 
-        return Common::kNoError;
+	return Common::kNoError;
 }
 
 //#if PLUGIN_ENABLED_DYNAMIC(STMIDI)
-        //REGISTER_PLUGIN_DYNAMIC(STMIDI, PLUGIN_TYPE_MUSIC, StMidiMusicPlugin);
+	//REGISTER_PLUGIN_DYNAMIC(STMIDI, PLUGIN_TYPE_MUSIC, StMidiMusicPlugin);
 //#else
-        REGISTER_PLUGIN_STATIC(STMIDI, PLUGIN_TYPE_MUSIC, StMidiMusicPlugin);
+	REGISTER_PLUGIN_STATIC(STMIDI, PLUGIN_TYPE_MUSIC, StMidiMusicPlugin);
 //#endif
 
 #endif
diff --git a/backends/midi/timidity.cpp b/backends/midi/timidity.cpp
index eeaf872747..642ddf6917 100644
--- a/backends/midi/timidity.cpp
+++ b/backends/midi/timidity.cpp
@@ -92,49 +92,50 @@ class MidiDriver_TIMIDITY : public MidiDriver_MPU401 {
 public:
 	MidiDriver_TIMIDITY();
 
-	int	open();
-	void	close();
-	void	send(uint32 b);
-	void	sysEx(const byte *msg, uint16 length);
+	int open();
+	bool isOpen() const { return _isOpen; }
+	void close();
+	void send(uint32 b);
+	void sysEx(const byte *msg, uint16 length);
 
 private:
 	/* standart routine to extract ip address from a string */
-	in_addr_t	host_to_addr(const char* address);
+	in_addr_t host_to_addr(const char* address);
 
 	/* creates a tcp connection to TiMidity server, returns filedesc (like open()) */
-	int	connect_to_server(const char* hostname, unsigned short tcp_port);
+	int connect_to_server(const char* hostname, unsigned short tcp_port);
 
 	/* send command to the server; printf-like; returns reply string */
-	char	*timidity_ctl_command(const char *fmt, ...) GCC_PRINTF(2, 3);
+	char *timidity_ctl_command(const char *fmt, ...) GCC_PRINTF(2, 3);
 
 	/* timidity data socket-related stuff */
-	void	timidity_meta_seq(int p1, int p2, int p3);
-	int	timidity_sync(int centsec);
-	int	timidity_eot();
+	void timidity_meta_seq(int p1, int p2, int p3);
+	int timidity_sync(int centsec);
+	int timidity_eot();
 
 	/* write() analogue for any midi data */
-	void	timidity_write_data(const void *buf, size_t nbytes);
+	void timidity_write_data(const void *buf, size_t nbytes);
 
 	/* get single line of server reply on control connection */
-	int	fdgets(char *buff, size_t buff_size);
+	int fdgets(char *buff, size_t buff_size);
 
 	/* teardown connection to server */
-	void	teardown();
+	void teardown();
 
 	/* close (if needed) and nullify both control and data filedescs */
-	void	close_all();
+	void close_all();
 
 private:
-	bool	_isOpen;
-	int	_device_num;
+	bool _isOpen;
+	int _device_num;
 
-	int	_control_fd;
-	int	_data_fd;
+	int _control_fd;
+	int _data_fd;
 
 	/* buffer for partial data read from _control_fd - from timidity-io.c, see fdgets() */
-	char	_controlbuffer[BUFSIZ];
-	int	_controlbuffer_count;	/* beginning of read pointer */
-	int	_controlbuffer_size;	/* end of read pointer */
+	char _controlbuffer[BUFSIZ];
+	int _controlbuffer_count;	/* beginning of read pointer */
+	int _controlbuffer_size;	/* end of read pointer */
 };
 
 MidiDriver_TIMIDITY::MidiDriver_TIMIDITY() {
@@ -149,9 +150,9 @@ MidiDriver_TIMIDITY::MidiDriver_TIMIDITY() {
 }
 
 int MidiDriver_TIMIDITY::open() {
-	char	*res;
-	char	timidity_host[MAXHOSTNAMELEN];
-	int	timidity_port, data_port, i;
+	char *res;
+	char timidity_host[MAXHOSTNAMELEN];
+	int timidity_port, data_port, i;
 
 	/* count ourselves open */
 	if (_isOpen)
diff --git a/backends/midi/windows.cpp b/backends/midi/windows.cpp
index b585b71fbe..aad7f48d94 100644
--- a/backends/midi/windows.cpp
+++ b/backends/midi/windows.cpp
@@ -61,6 +61,7 @@ private:
 public:
 	MidiDriver_WIN(int deviceIndex) : _isOpen(false), _device(deviceIndex) { }
 	int open();
+	bool isOpen() const { return _isOpen; }
 	void close();
 	void send(uint32 b);
 	void sysEx(const byte *msg, uint16 length);
@@ -93,6 +94,8 @@ void MidiDriver_WIN::close() {
 }
 
 void MidiDriver_WIN::send(uint32 b) {
+	assert(_isOpen);
+
 	union {
 		DWORD dwData;
 		BYTE bData[4];