shithub: choc

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make two variables static

The event_t structs in the mouse button and wheel handling routines
have their address passed outside the scope of those routines, which
is undefined behaviour. Mark them as static to address this.

This makes them singletons, meaning no more than one of each type
of event per button/axis can occur in a single tic, but that seems
to be true anyway.

I_ReadMouse and I_HandleKeyboardEvent also have this problem but I
am less confident that applying static is sufficient to fix them.
Mark them with XXX comments to make sure we don't forget.

--- a/src/i_input.c

+++ b/src/i_input.c

@@ -242,6 +242,8 @@

 void I_HandleKeyboardEvent(SDL_Event *sdlevent)

 {

+    // XXX: passing pointers to event for access after this function

+    // has terminated is undefined behaviour

     event_t event;

     switch (sdlevent->type)

@@ -305,7 +307,7 @@

 static void UpdateMouseButtonState(unsigned int button, boolean on)

 {

-    event_t event;

+    static event_t event;

     if (button < SDL_BUTTON_LEFT || button > MAX_MOUSE_BUTTONS)

     {

@@ -360,7 +362,7 @@

     // SDL2 distinguishes button events from mouse wheel events.

     // We want to treat the mouse wheel as two buttons, as per

     // SDL1

-    event_t up, down;

+    static event_t up, down;

     int button;

     if (wheel->y <= 0)

@@ -450,6 +452,8 @@

             ev.data3 = 0;

         }

+        // XXX: undefined behaviour since event is scoped to

+        // this function

         D_PostEvent(&ev);

     }

 }