In order to move the WindowServer to userspace, I have to eliminate its
dependence on system call facilities. The communication channel with each
client needs to be message-based in both directions.
GMenu now has an "on_item_activation" callback that fires whenever one
of its items are activated. The menu item identifier is used to distinguish
between items.
Use this to implement font switching in Terminal. :^)
To facilitate listening for action on arbitrary file descriptors,
I've added a GNotifier class. It's quite simple but very useful:
GNotifier notifier(fd, GNotifier::Read);
notifier.on_ready_to_read = [this] (GNotifier& fd) {
// read from fd or whatever else you like :^)
};
The callback will get invoked by GEventLoop when select() says we
have something to read on the fd.
My needs are really quite simple, so I'm just going to add what I need
as I go along. The first thing I needed was a simple box layout with
widgets being able to say whether they prefer fixed or fill for both
their vertical and horizontal sizes.
I also made a simple GStatusBar so FileManager can show how many bytes
worth of files are in the current directory.
This widget is far from finished, but it's off to a good start.
Also added a GResizeEvent and GWidget::resize_event() so that widgets
can react to being resized.
Let GButton have an optional icon (GraphicsBitmap) that gets rendered in the
middle of the button if present.
Also add GraphicsBitmap::load_from_file() which allows mmap'ed RGBA32 files.
I wrote a little program to take "raw" files from GIMP and swizzle them into
the correct byte order.
While working on the ELF loader I was trying to keep binaries as simple as
possible so I could understand them easily. Now that the ELF loader is mature
and working fine, we can move closer towards ld defaults.
Clicking the button generates a WindowCloseRequest event which the client app
then has to deal with. The default behavior for GWindow is to close() itself.
I also added a flag, GWindow::should_exit_event_loop_on_close() which does
what it sounds like it does.
This patch exposed some bugs in GWindow and GWidget teardown.
Font now uses the same in-memory format as the font files we have on disk.
This allows us to simply mmap() the font files and not use any additional
memory for them. Very cool! :^)
Hacking on this exposed a bug in file-backed VMObjects where the first client
to instantiate a VMObject for a specific inode also got to decide its size.
Since file-backed VMObjects always have the same size as the underlying file,
this made no sense, so I removed the ability to even set a size in that case.
GObjects can now register a timer with the GEventLoop. This will eventually
cause GTimerEvents to be dispatched to the GObject.
This needed a few supporting changes in the kernel:
- The PIT now ticks 1000 times/sec.
- select() now supports an arbitrary timeout.
- gettimeofday() now returns something in the tv_usec field.
With these changes, the clock window in guitest2 finally ticks on its own.