Implement MIDI I/O support using RtMidi

src/qt/CMakeLists.txt

@@ -4,9 +4,10 @@ set(CMAKE_AUTOMOC ON)
 set(CMAKE_AUTOUIC ON)
 set(CMAKE_AUTORCC ON)
 
+find_package(PkgConfig)
 find_package(Threads REQUIRED)
 
-add_library(plat STATIC qt.c qt_main.cpp qt_platform.cpp qt_midi.cpp cpp11_thread.cpp)
+add_library(plat STATIC qt.c qt_main.cpp qt_platform.cpp cpp11_thread.cpp)
 add_library(ui STATIC
     qt_ui.cpp
     qt_cdrom.c
@@ -101,6 +102,21 @@ if (UNIX AND NOT APPLE)
     find_package(X11 REQUIRED)
     target_link_libraries(ui PRIVATE X11::X11)
     find_package(ECM NO_MODULE)
+    if (PkgConfig_FOUND)
+        pkg_check_modules(RTMIDI rtmidi)
+        if (RTMIDI_FOUND)
+            target_include_directories(plat PRIVATE ${RTMIDI_INCLUDE_DIRS})
+            target_link_directories(plat PRIVATE ${RTMIDI_LIBRARY_DIRS})
+            target_link_libraries(plat PRIVATE ${RTMIDI_LIBRARIES})
+            target_link_options(plat PRIVATE ${RTMIDI_LDFLAGS})
+            target_compile_options(plat PRIVATE ${RTMIDI_CFLAGS})
+            target_sources(plat PRIVATE rtmidi_midi.cpp)
+        else()
+            target_sources(plat PRIVATE qt_midi.cpp)
+        endif()
+    else()
+        target_sources(plat PRIVATE qt_midi.cpp)
+    endif()
     if (ECM_FOUND)
         list(APPEND CMAKE_MODULE_PATH ${ECM_MODULE_PATH})
         find_package(Wayland COMPONENTS Client)

src/qt/rtmidi_midi.cpp

@@ -0,0 +1,143 @@
+
+#include <RtMidi.h>
+#include <cstdint>
+#include <cstring>
+extern "C"
+{
+#include <86box/86box.h>
+#include <86box/midi.h>
+#include <86box/plat_midi.h>
+#include <86box/config.h>
+}
+
+extern "C" {
+
+static RtMidiOut* midiout = nullptr;
+static RtMidiIn* midiin = nullptr;
+static int midi_out_id = 0, midi_in_id = 0;
+static const int midi_lengths[8] = {3, 3, 3, 3, 2, 2, 3, 1};
+
+int plat_midi_write(uint8_t val)
+{ return 0; }
+
+void plat_midi_init()
+{
+    try
+    {
+        midiout = new RtMidiOut;
+    }
+    catch (RtMidiError& error)
+    {
+        pclog("Failed to initialize MIDI output: %s\n", error.getMessage().c_str());
+        return;
+    }
+    midi_out_id = config_get_int((char*)SYSTEM_MIDI_NAME, (char*)"midi", 0);
+    try
+    {
+        midiout->openPort(midi_out_id);
+    }
+    catch (RtMidiError& error)
+    {
+        pclog("Fallback to default MIDI output port: %s\n", error.getMessage().c_str());
+        try
+        {
+            midiout->openPort(0);
+        }
+        catch (RtMidiError& error)
+        {
+            pclog("Failed to initialize MIDI output: %s\n", error.getMessage().c_str());
+            delete midiout;
+            midiout = nullptr;
+            return;
+        }
+    }
+}
+
+void plat_midi_close()
+{
+    if (!midiout) return;
+    midiout->closePort();
+    delete midiout;
+    midiout = nullptr;
+}
+
+int plat_midi_get_num_devs()
+{
+    return midiout ? midiout->getPortCount() : 0;
+}
+
+void plat_midi_play_msg(uint8_t *msg)
+{
+    if (midiout) midiout->sendMessage(msg, midi_lengths[(msg[0] >> 4) & 7]);
+}
+
+void plat_midi_get_dev_name(int num, char *s)
+{
+	strcpy(s, midiout->getPortName(num).c_str());
+}
+
+void plat_midi_play_sysex(uint8_t *sysex, unsigned int len)
+{
+    if (midiout) midiout->sendMessage(sysex, len);
+}
+
+static void plat_midi_callback(double timeStamp, std::vector<unsigned char> *message, void *userData)
+{
+    if (message->size() <= 3) midi_in_msg(message->data());
+    else midi_in_sysex(message->data(), message->size());
+}
+
+void plat_midi_input_init(void)
+{
+    try
+    {
+        midiin = new RtMidiIn;
+    }
+    catch (RtMidiError& error)
+    {
+        pclog("Failed to initialize MIDI input: %s\n", error.getMessage().c_str());
+        return;
+    }
+    midi_in_id = config_get_int((char*)SYSTEM_MIDI_NAME, (char*)"midi_input", 0);
+    try
+    {
+        midiin->openPort(midi_in_id);
+    }
+    catch (RtMidiError& error)
+    {
+        pclog("Fallback to default MIDI input port: %s\n", error.getMessage().c_str());
+        try
+        {
+            midiin->openPort(0);
+        }
+        catch (RtMidiError& error)
+        {
+            pclog("Failed to initialize MIDI input: %s\n", error.getMessage().c_str());
+            delete midiin;
+            midiin = nullptr;
+            return;
+        }
+    }
+    midiin->setCallback(plat_midi_callback);
+}
+
+void plat_midi_input_close(void)
+{
+    midiin->cancelCallback();
+    midiin->closePort();
+    delete midiin;
+    midiin = nullptr;
+    return;
+}
+
+int plat_midi_in_get_num_devs(void)
+{
+    return midiin ? midiin->getPortCount() : 0;
+}
+
+void plat_midi_in_get_dev_name(int num, char *s)
+{
+	strcpy(s, midiin->getPortName(num).c_str());
+}
+
+}