Unfortunately this area is not standardized by POSIX. Linux uses an ioctl
which is not that bad, but I'd like to have a designated function. I'm not
sure if this facility is powerful enough and whether it should be improved.
Also note that I use a struct winsize as on Linux, but I use size_ts instead
for the heck of it. Perhaps I should use another name for the struct.
The console renderer now renders to a text buffer, which can be implemented
on any device, whether it's the VGA text buffer or a bitmap graphics device
with font rendering. This replaces the older code that could only render to
a VGA framebuffer and where the input parsing was tightly coupled with the
device rendering phase.
This enables useful features such as directories, CRC32 checksums, and other
useful features. The initrdfs in the kernel is now hooked up against the new
API, although the kernel's current limited FS support is a problem for now.
To work around that, directories are not supported at runtime, although the
internal API understands them wonderfully. This will be fixed when the
kernel gets a real VFS.
Any detected COM ports available as /dev/comN.
It currently utilizes AGAIN to do polling in user-space. This prevents it
from locking up the whole system and makes it respond to the SIGINT hack.
There is also a more reliable and faster polling-blocking mode, but it locks
up the entire system.
The main interrupt mode is broken, perhaps by a bug in VirtualBox.
This will allow development of a better terminal providing stdin.
Added new system calls settermmode(2) and gettermmode(2) declared in
<sys/termmode.h>. They allow querying and changing the current mode of
terminals (enabling raw keyboard data, signal handling, line buffering,
UTF-8 encoding stdin, and more). However, all that is unsupported by the
current terminal device driver.
Added KBKEY_ENCODE and KBKEY_DECODE macros to <sys/keycodes.h> which allows
encoding the kbkey format in UTF-32 characters.
Read operations are enabled by default, but you must set DISKWRITE=1 in
makeflags before write operations are permitted. This protects against
accidentally corrupting the existing filesystems on the system.
When compiled with gcc 4.6.1, 32-bit Sortix would triple fault during
early boot: When the TLB is being flushed, somehow a garbage value had
sneaked into Sortix::Memory::currentdir, and a non-page aligned (and
garbage) page directory is loaded. (Triple fault, here we come!)
However, adding a volatile addr_t foo after the currentdir variable
actually caused the system to boot correctly - the garbage was written
into that variable instead. To debug the problem, I set the foo value
to 0: as long as !foo (hence the name nofoo) everything was alright.
After closer examination I found that the initrd open code wrote to a
pointer supplied by kernel.cpp. The element pointed to was on the
stack. Worse, its address was the same as currentdir (now foo).
Indeed, the stack had gone into the kernel's data segment!
Turns out that this gcc configuration stores variables in the data
segment in the reverse order they are defined in, whereas previous
compilers did the opposite. The hack used to set up the stack during
early boot relied on this (now obviously incorrect) fact.
In effect, the stack was initialized to the end of the stack, not
the start of it: completely ignoring all the nice stack space
allocated in kernel.cpp.
I did not see that one coming.
This fixes issues where it did not fit into the first few MiB,
or that GRUB loaded it someplace weird.
The kernel heap is now also protected against growing into the
ramdisk and the kernel stack.
Fixed 64-bit-ness bug in BSR() and BSF().
Added 64-bit system call stubs in libmaxsi.
Added a Elf64 program loader.
Fixed uninitialized memory bug in the scheduler.
x64/boot.s now takes care of user-space memory permissions.
Fixed bug in x64/syscall.s
That's right. The system now boots in 64-bit mode.
It is horribly unstable, though.
This commit got completely out of control.
Added the fork(), getpid(), getppid(), sleep(), usleep() system calls, and
aliases in the Maxsi:: namespace.
Fixed a bug where zero-byte allocation would fail.
Worked on the DescriptorTable class which now works and can fork.
Got rid of some massive print-registers statements and replaced them with
the portable InterruptRegisters::LogRegisters() function.
Removed the SysExecuteOld function and replaced it with Process::Execute().
Rewrote the boot sequence in kernel.cpp such that it now loads the system
idle process 'idle' as PID 0, and the initization process 'init' as PID 1.
Rewrote the SIGINT hack.
Processes now maintain a family-tree structure and keep track of their
threads. PIDs are now allocated using a simple hack. Virtual memory
per-process can now be allocated using a simple hack. Processes can now be
forked. Fixed the Process::Execute function such that it now resets the
stack pointer to where the stack actually is - not just a magic value.
Removed the old and ugly Process::_endcodesection hack.
Rewrote the scheduler into a much cleaner and faster version. Debug code is
now moved to designated functions. The noop kernel-thread has been replaced
by a simple user-space infinite-loop program 'idle'.
The Thread class has been seperated from the Scheduler except in Scheduler-
related code. Thread::{Save,Load}Registers has been improved and has been
moved to $(CPU)/thread.cpp. Threads can now be forked. A new CreateThread
function creates threads properly and portably.
Added a MicrosecondsSinceBoot() function.
Fixed a crucial bug in MemoryManagement::Fork().
Added an 'idle' user-space program that is a noop infinite loop, which is
used by the scheduler when there is nothing to do.
Rewrote the 'init' program such that it now forks off a shell, instead of
becoming the shell.
Added the $$ (current PID) and $PPID (parent PPID) variables to the shell.
1) The PML2 was not initialized to zeroes, thus leaving some bits behind that
caused the fork code to go crazy, forking the unforkable, and mapping addresses
that never, ever, should have been mapped, leaving behind a trail of page faults
and general protection faults on some computers, while other computers worked
because the uninitalized memory just wasn't uninitialized enough. Yep, this was
a schrödinbug!
2) Fixed a time bomb. The kernel heap was accidentally put such that whenever a
few megabytes were allocated, it would begin overwriting the physical page stack
causing unthinkable events to unfold and would probably be even more obscure to
debug than 1).
Oh, and some string errors fixed and removed RunApplication from kernel.cpp,
funny thing that even linked in the first place. Guess, the optimizer actually
did work for once. :)
uintptr_t is now replaced with addr_t when referring to physical memory
addresses in Sortix. Many bugs in the previous memory management code have been
fixed. The new interface is less flexible - but should prove more solid as the
nasty internals have been hidden away. The current interface design should also
make the code more 64-bit ready/friendly. And so on.
Jonas 'Sortie' Termansen