* [metal] Copy program pages to extended memory at startup
* [metal] Reclaim base memory pages for later app use
* [metal] Load program pages beyond 1st 440 KiB to extended memory
o//examples/hellolua.com now runs correctly under QEMU (in
legacy BIOS mode).
* [metal] Place GDT in read/write segment
The CPU absolutely needs to alter the GDT when loading the
task register (via ltr). To account for this, I move the
GDT into a read/write data section. There is still a "rump"
read-only GDT in the text section that is used by the real
mode bootloader.
We also delay the loading of the task register (ltr) until
after the IDT and TSS are finally set up.
* [metal] Get examples/vga2.c serial output working for UEFI boot
* [metal] Get examples/vga2.c VGA output working for UEFI boot
* [metal] Allow munmap() to reclaim dynamically allocated pages
* Place TLS sections right after .text, not after embedded zip file
Co-authored-by: tkchia <tkchia-cosmo@gmx.com>
- Exhaustively document cancellation points
- Rename SIGCANCEL to SIGTHR just like BSDs
- Further improve POSIX thread cancellations
- Ensure asynchronous cancellations work correctly
- Elevate the quality of getrandom() and getentropy()
- Make futexes cancel correctly on OpenBSD 6.x and 7.x
- Add reboot.com and shutdown.com to examples directory
- Remove underscore prefix from awesome timespec_*() APIs
- Create assertions that help verify our cancellation points
- Remove bad timespec APIs (cmp generalizes eq/ne/gt/gte/lt/lte)
- ASAN memory morgue is now lockless
- Make C11 atomics header more portable
- Rewrote pthread keys support to be lockless
- Simplify Python's unicode table unpacking code
- Make crash report write(2) closer to being atomic
- Make it possible to strace/ftrace a single thread
- ASAN now checks nul-terminated strings fast and properly
- Windows fork() now restores TLS memory of calling thread
- use PAGE_RSRV bit (originally only for blinkenlights),
rather than PAGE_V bit, to indicate that a virtual address
page has been reserved — this should allow a program to
create & reserve inaccessible "guard pages"
- mark page table entries for non-code pages with PAGE_XD bit,
which should be supported on (circa) post-2004 x86-64 CPUs
* [metal] Refactoring: separate out sys_writev_vga() and _vga_init() modules
* [metal] Read VGA info from BDA before long mode entry, not after
If using a pre-existing VGA text console, the VGA initialization
code now retrieves the cursor position & character height from
the BIOS data area while still in real mode — rather than
reading from the BIOS data area only after entering long mode.
(This should help make the code more correct, if Cosmopolitan
were to support UEFI graphics output in the future. If the
program were booted via UEFI, then the long mode IsMetal()
code would still be activated, but the BIOS data area might
not have been initialized in that case.)
This change also means that there are now a few more fields
in the `struct mman`.
* [metal] VGA console can now show "screen of death" upon a crash
There is now a new function _klog_vga(), which can be called
by kprintf() to output system messages — e.g. information about
CPU exceptions — on the VGA screen.
* [metal] CPU exception handler now dumps cr2 value
* [metal] Add demo of program crash reporting w/ bare metal VGA TTY
* [metal] Reduce size of "screen of death" code
* Test output of colors for VGA graphics modes in examples/vga.c
* [metal] Character output in VGA graphics modes is mostly working
* [metal] Mention magic key to switch video mode, at bootup
This makes breaking changes to add underscores to many non-standard
function names provided by the c library. MODE=tiny is now tinier and
we now use smaller locks that are better for tiny apps in this mode.
Some headers have been renamed to be in the same folder as the build
package, so it'll be easier to know which build dependency is needed.
Certain old misguided interfaces have been removed. Intel intrinsics
headers are now listed in libc/isystem (but not in the amalgamation)
to help further improve open source compatibility. Header complexity
has also been reduced. Lastly, more shell scripts are now available.
If your main module has this declaration:
STATIC_YOINK("vga_console");
Then a VGA driver will be linked into your executable which
displays your stdio characters on the PC display, whereas
before we could only use the serial port. Your display is an
ANSI terminal and it's still a work in progress.
