davix operating system kernel

This is a personal hobby project that I am doing to challenge myself and to
learn about the inner workings of operating systems. Currently, it only targets
64-bit x86, since that is the architecture my computer is based on.

	Building it

A Unix-like host with GNU GCC and GNU make is recommended (though it is probably
possible to build with LLVM instead of GCC, and WSL might work).

To build the kernel, run 'make'. You must have GNU make installed, and GCC
cross-compilers for 'x86_64-elf' available in the path. A kernel binary will
be produced in 'build/davix'. The kernel is a multiboot2 kernel and can be
loaded with a bootloader like GRUB.

Pro tip: If you are on an x86_64 platform but don't have GCC cross-compilers
installed, instead of compiling and installing them yourself, you can symlink
the needed tools from '/usr/local/bin/x86_64-elf-whatever' to your installed
binaries (i.e. 'ln -s /usr/bin/gcc /usr/local/bin/x86_64-elf-gcc'). This
"works on my machine"(TM), but may cause bogus builds on other machines.

	Running it

Recommended way is QEMU, but it probably works in Bochs as well. You should
enable the QEMU/Bochs debugcon (also known as the "port 0xe9 hack") if you
want any kernel output. The './run' script in the project root (same as this
README) will build the kernel, produce a GRUB rescue disc with it installed,
and launch QEMU. This requires GRUB to be installed. The './run' script is
quite sophisticated, run './run --help' for details about what it can do.

Do not run the kernel on real hardware.

	Configuring the kernel

To configure the kernel, create a 'user' directory and put a file named
'config.h' in it. In 'config.h', it is possible to override macros defined in
'include/builtin_config.h'.