Max Horn 8982fff1b7 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.

2011-03-22 23:51:47 +01:00

..

alsa.cpp

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

2011-03-22 23:51:47 +01:00

camd.cpp

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

2011-03-22 23:51:47 +01:00

coreaudio.cpp

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

2011-03-22 23:51:47 +01:00

coremidi.cpp

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

2011-03-22 23:51:47 +01:00

dmedia.cpp

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

2011-03-22 23:51:47 +01:00

seq.cpp

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

2011-03-22 23:51:47 +01:00

stmidi.cpp

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

2011-03-22 23:51:47 +01:00

timidity.cpp

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

2011-03-22 23:51:47 +01:00

windows.cpp

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

2011-03-22 23:51:47 +01:00