Calling open() on input devices can generate device I/O which blocks
the main thread and causes dropped frames. Using stat() we can avoid
opening anything unless /dev/input has changed since we last polled.
We could have used something fancy like inotify, but it didn't seem
worth the added complexity for this uncommon non-udev case.
Eric Shepherd
Currently, SDL on Cocoa macOS creates a rudimentary menu bar programmatically if none is already present when the app is registered during setup.
SDL could be much more easily and flexibly used on macOS if upon finding that no menus are currently in place, it first looked for the application's main menu nib or xib file and, if found, loaded that instead of programmatically building the menus.
This would then let developers simply drop in a nib file with a menu bar defined in it and it would be installed and used automatically.
Attached is a patch that does just this. It changes the SDL_cocoaevents.m file to:
* In Cocoa_RegisterApp(), before calling CreateApplicationMenus(), it calls a new function, LoadMainMenuNibIfAvailable(), which attempts to load and install the main menu nib file, using the nib name fetched from the Info.plist file. If that succeeds, LoadMainMenuNibIfAvailable() returns true; otherwise false.
* If LMMNIA() returns false, CreateApplicationMenus() is called to programmatically build the menus as before.
* Otherwise, we're done, and using the menus from the nib/xib file!
I made these changes to support a project I'm working on, and felt they were useful enough to be worth offering them for uplift. They should have zero impact on existing projects' behavior, but make Cocoa SDL development miles easier.
(note from PulkoMandy on Bugzilla #4442 about why this is a desirable patch:
"The event mask: note that the window and GL view run in their own thread
which I don't expect to be too much CPU bound, and will quickly pop these
messages and forward them to the main thread in our SDL code. Therefore the
B_NO_POINTER_HISTORY should be no problem, and is the default on Haiku
anyway (it was not in BeOS, but we changed that and added a
B_FULL_POINTER_HISTORY flag to request the old behavior explicitly). So, this
seems fine.")
Partially fixes Bugzilla #4442.
