romain.lacroix
For the windows implementation of SDL_ShowMessageBox() : ./src/video/windows/SDL_windowsmessagebox.c:345 WIN_ShowMessageBox()
The implementation in 2.0.4 uses "button index" for parameter "id" of function AddDialogButton().
It then expects the value provided in param wParam of function MessageBoxDialogProc() to be a valid index of a button.
It uses this value to index in the array of buttons when DialogBoxIndirect() returns (line 474 : *buttonid = buttons[which].buttonid;)
However, when dismissing this box with Escape, the return value of DialogBoxIndirect will be SDL_MESSAGEBOX_BUTTON_ESCAPEKEY_DEFAULT (=2) which is not always a valid index of array buttons.
When the array buttons has a length less or equal than 2, the memory access is invalid; I can see that the value written to *buttonId is uninitialized memory (random value).
The fix I propose : use value "buttonid" (field of button) for parameter "id" of AddDialogButton(), then copy return value of DialogBoxIndirect() in *buttonid. This way, we will not use an out-of-bounds index in array buttons.
Jan Hellwig
On Windows, you are able to navigate between the buttons on a MessageBox that was created using SDL_ShowMessageBox using the arrow keys. However, if you press the left arrow key, the selection jumps to the button on the right of the currently selected one (and vice versa).
This can be fixed by reversing the order in which the buttons are added to the dialog.
The attached patch files fixes this problem. However the first press of an arrow key leads to the selection of the leftmost or rightmost button on the MessageBox, not to the selection of the button left/right of the one that is selected by default.
The internal function SDL_EGL_LoadLibrary() did not delete and remove a mostly
uninitialized data structure if loading the library first failed. A later try to
use EGL then skipped initialization and assumed it was previously successful
because the data structure now already existed. This led to at least one crash
in the internal function SDL_EGL_ChooseConfig() because a NULL pointer was
dereferenced to make a call to eglBindAPI().
