Commit graph

14 commits

Author SHA1 Message Date
Justine Tunney
b3838173ec Remove undefined behaviors 2021-05-16 11:16:28 -07:00
Justine Tunney
edd9297eba Support malloc() on bare metal
Your Actually Portable Executables now contains a simple virtual memory
that works similarly to the Linux Kernel in the sense that it maps your
physical memory to negative addresses. This is needed to support mmap()
and malloc(). This functionality has zero code size impact. For example
the MODE=tiny LIFE.COM executable is still only 12KB in size.

The APE bootloader code has also been simplified to improve readibility
and further elevate the elegance by which we're able to support so many
platforms thereby enhancing verifiability so that we may engender trust
in this bootloading process.
2021-02-24 00:53:24 -08:00
Justine Tunney
9f149e1de3 Elevate .text.syscall to .privileged
It turns out adding OpenBSD msyscall() origin verification broke the
--ftrace flag. The executable needs to issue raw syscalls while it's
rewriting itself. So they need to be in the same section, and that's
just plain simpler too.
2021-02-06 04:49:22 -08:00
Justine Tunney
c843243322 Implement more security stuff
- Support deterministic stacks on OpenBSD
- Support OpenBSD system call origin verification
- Fix overrun by one in chibicc string token allocator
- Get all chibicc tests passing under Address Sanitizer
2021-02-02 20:21:06 -08:00
Justine Tunney
1ff9ab95ac Make C memory safe like Rust
This change enables Address Sanitizer systemically w/ `make MODE=dbg`.
Our version of Rust's `unsafe` keyword is named `noasan` which is used
for two functions that do aligned memory chunking, like `strcpy.c` and
we need to fix the tiny DEFLATE code, but that's it everything else is
fabulous you can have all the fischer price security blankets you need

Best of all is we're now able to use the ASAN data in Blinkenlights to
colorize the memory dumps. See the screenshot below of a test program:

  https://justine.lol/blinkenlights/asan.png

Which is operating on float arrays stored on the stack, with red areas
indicating poisoned memory, and the green areas indicate valid memory.
2021-02-01 03:58:46 -08:00
Justine Tunney
9df2cef4c4 Enhance chibicc 2020-12-09 04:00:48 -08:00
Justine Tunney
8da931a7f6 Add chibicc
This program popped up on Hacker News recently. It's the only modern
compiler I've ever seen that doesn't have dependencies and is easily
modified. So I added all of the missing GNU extensions I like to use
which means it might be possible soon to build on non-Linux and have
third party not vendor gcc binaries.
2020-12-06 16:20:21 -08:00
Justine Tunney
ea0b5d9d1c Get Cosmopolitan into releasable state
A new rollup tool now exists for flattening out the headers in a way
that works better for our purposes than cpp. A lot of the API clutter
has been removed. APIs that aren't a sure thing in terms of general
recommendation are now marked internal.

There's now a smoke test for the amalgamation archive and gigantic
header file. So we can now guarantee you can use this project on the
easiest difficulty setting without the gigantic repository.

A website is being created, which is currently a work in progress:
https://justine.storage.googleapis.com/cosmopolitan/index.html
2020-11-25 08:19:00 -08:00
Justine Tunney
b6793d42d5 Add The LISP Challenge
This change introduces a 2.5kb program that's comes pretty close so far
to bootstrapping John McCarthy's metacircular evaluator on bare metal.
2020-10-01 01:20:13 -07:00
Justine Tunney
23d333c090 Make more improvements
This change includes many bug fixes, for the NT polyfills, strings,
memory, boot, and math libraries which were discovered by adding more
tools for recreational programming, such as PC emulation. Lemon has also
been vendored because it works so well at parsing languages.
2020-09-28 01:20:34 -07:00
Justine Tunney
bd29223891 Fix bugs and have emulator emulate itself 2020-08-31 05:17:31 -07:00
Justine Tunney
5aabacb361 Add pseudoteletypewriter to emulator
https://justine.storage.googleapis.com/emulator628.mp4
2020-08-29 23:51:09 -07:00
Justine Tunney
f4f4caab0e Add x86_64-linux-gnu emulator
I wanted a tiny scriptable meltdown proof way to run userspace programs
and visualize how program execution impacts memory. It helps to explain
how things like Actually Portable Executable works. It can show you how
the GCC generated code is going about manipulating matrices and more. I
didn't feel fully comfortable with Qemu and Bochs because I'm not smart
enough to understand them. I wanted something like gVisor but with much
stronger levels of assurances. I wanted a single binary that'll run, on
all major operating systems with an embedded GPL barrier ZIP filesystem
that is tiny enough to transpile to JavaScript and run in browsers too.

https://justine.storage.googleapis.com/emulator625.mp4
2020-08-25 04:43:42 -07:00
Justine Tunney
c91b3c5006 Initial import 2020-06-15 07:18:57 -07:00