Don't delete non-existing files in make clean

Make clean tried to delete init.cpio and dominos.iso which caused a warning
if the files didn't exist. The Makefile now checks for the existence of the
files before trying to delete them.

Signed-off-by: Joel Nider <joel@nider.org>
JOEL4: fixed warning with syscall function type

Instead of casting each syscall function to a type that is wrong and unused,
the table is now declared as void* and each function can have its own parameters.

Signed-off-by: Joel Nider <joel@nider.org>
JOEL4: fixed warning in cast for BootInfo

Pointer arithmetic that was not being casted to a number was causing a warning.

Signed-off-by: Joel Nider <joel@nider.org>
JOEL4: fix L4_DebugPutChar implementation

Added eax and ecx to the clobber list so GCC knows not to reuse those registers
without saving them first. Eax was being given double duty, causing the code to
enter an infinite loop. Now printf works as expected with %x.

Signed-off-by: Joel Nider <joel@nider.org>
JOEL4: boot info from the offset of the KIP

The boot info struct was given an absolute address which was given in kernel
space. This should be part of the user space address, in the KIP page.

Signed-off-by: Joel Nider <joel@nider.org>
KOS: missing $ in gdt constant (asm)

Even though the KOS kernel is no longer being developed, it is nonetheless
being used as a reference since it is posted on github and shows up in
searches. In this light I feel it is important to fix any bugs as to not
mislead people accidentally who may rely on this code without realizing its
status.

Constant values in AT&T style assembly should start with a $.
Thanks to Lars Gehlert for pointing out this bug.

Signed-off-by: Joel Nider <joel@nider.org>
Added kernel debug build option

From the top makefile, you can now build the kernel with debugging support by
typing 'make debug' rather than 'make'. This uses a make variable called
DEBUG, which could also be passed on the command line with 'make DEBUG=y'.

Signed-off-by: Joel Nider <joel@nider.org>
JOEL4: leave system call parameters on stack

Trial implementation. Seems to work, but I still have some doubts about its
security. A more secure implementation may reduce efficiency. I will use it
for now, but will wait for some performance testing before making a final
judgement.

Signed-off-by: Joel Nider <joel@nider.org>
latest development notes

Signed-off-by: Joel Nider <joel@nider.org>
version 173

Signed-off-by: Joel Nider <joel@nider.org>
Added support for bochs 2.6

Generally I use the internal debugger in bochs because I can understand it
better than the other debugger choices available.

Signed-off-by: Joel Nider <joel@nider.org>
Merge pull request #31 from jnider/dev

Dev