Add WIP _XEventProc code

dep/lglw/lglw_linux.c

@@ -335,6 +335,93 @@ static void loc_destroy_hidden_window(lglw_int_t *lglw) {
 }
 
 
+// ---------------------------------------------------------------------------- loc_setEventProc
+// https://www.kvraudio.com/forum/viewtopic.php?t=387924
+// https://github.com/Ardour/ardour/blob/master/gtk2_ardour/linux_vst_gui_support.cc
+// https://discourse.ardour.org/t/overtonedsp-plugins/90115/22
+// https://github.com/amsynth/amsynth/blob/4a87798e650c6d71d70274a961c9b8d98fc6da7e/src/amsynth_vst.cpp
+// https://github.com/rsenn/eXT2/blob/7f00a09561ded8175ffed2f4912dad74e466a1c7/vstplugins/vstgui/vstgui.cpp
+// https://github.com/COx2/DistortionFilter/blob/c6a34fb56b503a6e95bf0975e00f438bbf4ff52a/juce/modules/juce_audio_processors/format_types/juce_VSTPluginFormat.cpp
+
+// Very simple function to test _XEventProc is properly called
+void loc_eventProc(void *xevent) {
+   // lglw_log("XEventProc");
+   printf("XEventProc\n");
+}
+
+// Pulled from the Renoise 64-bit callback example
+// Unsure what data was supposed to be, but swapping it to a function name did not work
+// This does nothing, no event proc found
+// TODO: 32-bit support
+// void loc_setEventProc (Display *display, Window window) {
+//    size_t data = (size_t)loc_eventProc;
+//    long temp[2];
+
+//    // Split the 64 bit pointer into a little-endian long array
+//    temp[0] = (long)(data & 0xffffffffUL);
+//    temp[1] = (long)(data >> 32L);
+
+//    Atom atom = XInternAtom(display, "_XEventProc", False);
+//    XChangeProperty(display, window, atom, atom, 32,
+//       PropModeReplace, (unsigned char*)temp, 2);
+// }
+
+// Pulled from the eXT2 example
+// TODO: 32-bit support
+void loc_setEventProc (Display *display, Window window) {
+   void* data = (void*)&loc_eventProc; // swapped the function name here
+
+   Atom atom = XInternAtom(display, "_XEventProc", False);
+   XChangeProperty(display, window, atom, atom, 32,
+      PropModeReplace, (unsigned char*)&data, 1); // 1 instead of 2 will crash Ardour, 2 will not do anything
+}
+
+// Pulled from the amsynth example
+// Simply swapped out the function names, crashes Ardour in the same was as the others
+// void loc_setEventProc (Display *display, Window window) {
+// #ifdef BUILD_64
+//    //
+//    // JUCE calls XGetWindowProperty with long_length = 1 which means it only fetches the lower 32 bits of the address.
+//    // Therefore we need to ensure we return an address in the lower 32-bits of address space.
+//    //
+
+//    // based on mach_override
+//    static const unsigned char kJumpInstructions[] = {
+//          0xFF, 0x25, 0x00, 0x00, 0x00, 0x00,
+//          0x00, 0x00, 0x00, 0x00,
+//          0x00, 0x00, 0x00, 0x00
+//    };
+//    static const int kJumpAddress = 6;
+
+//    static char *ptr;
+//    if (!ptr) {
+//       ptr = (char *)mmap(0,
+//                      PAGE_SIZE,
+//                      PROT_READ | PROT_WRITE | PROT_EXEC,
+//                      MAP_ANONYMOUS | MAP_PRIVATE | MAP_32BIT,
+//                      0, 0);
+//       if (ptr == MAP_FAILED) {
+//          perror("mmap");
+//          ptr = 0;
+//          return;
+//       } else {
+//          memcpy(ptr, kJumpInstructions, sizeof(kJumpInstructions));
+//          *((uint64_t *)(ptr + kJumpAddress)) = (uint64_t)(&loc_eventProc);
+//          msync(ptr, sizeof(kJumpInstructions), MS_INVALIDATE);
+//       }
+//    }
+
+//    long temp[2] = {(long)ptr, 0};
+//    Atom atom = XInternAtom(display, "_XEventProc", False);
+//    XChangeProperty(display, window, atom, atom, 32, PropModeReplace, (unsigned char *)temp, 2);
+// #else
+//    long temp[1] = {(long)(void *)(&loc_eventProc)};
+//    Atom atom = XInternAtom(display, "_XEventProc", False);
+//    XChangeProperty(display, window, atom, atom, 32, PropModeReplace, (unsigned char *)temp, 1);
+// #endif
+// }
+
+
 // ---------------------------------------------------------------------------- lglw_window_open
 lglw_bool_t lglw_window_open (lglw_t _lglw, void *_parentHWNDOrNull, int32_t _x, int32_t _y, int32_t _w, int32_t _h) {
    lglw_bool_t r = LGLW_FALSE;
@@ -363,14 +450,29 @@ lglw_bool_t lglw_window_open (lglw_t _lglw, void *_parentHWNDOrNull, int32_t _x,
       lglw_log("lglw:lglw_window_open: 5\n");
       swa.border_pixel = 0;
       swa.colormap = lglw->cmap;
-      swa.event_mask = EnterWindowMask | LeaveWindowMask;
-      lglw->win.xwnd = XCreateWindow(lglw->xdsp, lglw->parent_xwnd,
+      swa.event_mask = EnterWindowMask | LeaveWindowMask | KeyPressMask | KeyReleaseMask | ButtonPressMask | ButtonReleaseMask;
+      lglw->win.xwnd = XCreateWindow(lglw->xdsp, DefaultRootWindow(lglw->xdsp),
          0, 0, _w, _h, 0, CopyFromParent, InputOutput,
          lglw->vi->visual, CWBorderPixel | CWColormap | CWEventMask, &swa);
 
       lglw_log("lglw:lglw_window_open: 6\n");
       XSetStandardProperties(lglw->xdsp, lglw->win.xwnd, "LGLW", "LGLW", None, NULL, 0, NULL);
 
+      // Setup the event proc now, on the parent window as well just for the debug host
+      // It was simpler to do this than check in the debug host for the reparent event
+      lglw_log("lglw:lglw_window_open: 7\n");
+      loc_setEventProc(lglw->xdsp, lglw->win.xwnd);
+      loc_setEventProc(lglw->xdsp, lglw->parent_xwnd);
+
+      // Some hosts only check and store the callback when the Window is reparented
+      // Since creating the Window with a Parent may or may not do that, but the callback is not set,
+      // ... it's created as a root window, the callback is set, and then it's reparented
+      if (0 != _parentHWNDOrNull)
+      {
+         lglw_log("lglw:lglw_window_open: 8\n");
+         XReparentWindow(lglw->xdsp, lglw->win.xwnd, lglw->parent_xwnd, 0, 0);
+      }
+
       lglw_log("lglw:lglw_window_open: 9\n");
       XMapRaised(lglw->xdsp, lglw->win.xwnd);
       XSync(lglw->xdsp, False);