Fork notes
This fork of @jart's excellent redbean is the starting point for WebSocket support that will be merged back in.
WebSocket resources:
- RFC 6455 locally in both plaintext and html.
- An example WebSocket server in C# hosted on MDN
Fork Todo
- Learn how the ordinary HTTP BTD loop works in
cosmopolitan
/redbean
. - Use that loop to incrementally add WebSocket support:
- Handshake
- Frames
- Send/Recieve
- Closing
Meanwhile: I must learn the C toolchain on
(Ubuntu 22)
Linux and the code itself. This is only possible because of
the minimalist style in which @jart wrote redbean
.
Cosmopolitan
Cosmopolitan Libc makes C a build-once run-anywhere language, like Java, except it doesn't need an interpreter or virtual machine. Instead, it reconfigures stock GCC and Clang to output a POSIX-approved polyglot format that runs natively on Linux + Mac + Windows + FreeBSD + OpenBSD + NetBSD + BIOS with the best possible performance and the tiniest footprint imaginable.
Background
For an introduction to this project, please read the αcτµαlly pδrταblε εxεcµταblε blog post and cosmopolitan libc website. We also have API documentation.
Getting Started
If you're doing your development work on Linux or BSD then you need just five files to get started. Here's what you do on Linux:
wget https://justine.lol/cosmopolitan/cosmopolitan-amalgamation-2.0.1.zip
unzip cosmopolitan-amalgamation-2.0.1.zip
printf 'main() { printf("hello world\\n"); }\n' >hello.c
gcc -g -Os -static -nostdlib -nostdinc -fno-pie -no-pie -mno-red-zone \
-fno-omit-frame-pointer -pg -mnop-mcount -mno-tls-direct-seg-refs \
-o hello.com.dbg hello.c -fuse-ld=bfd -Wl,-T,ape.lds -Wl,--gc-sections \
-include cosmopolitan.h crt.o ape-no-modify-self.o cosmopolitan.a
objcopy -S -O binary hello.com.dbg hello.com
You now have a portable program.
./hello.com
bash -c './hello.com' # zsh/fish workaround (we patched them in 2021)
If ./hello.com
executed on Linux throws an error about not finding an
interpreter, it should be fixed by running the following command (although
note that it may not survive a system restart):
sudo sh -c "echo ':APE:M::MZqFpD::/bin/sh:' >/proc/sys/fs/binfmt_misc/register"
If the same command produces puzzling errors on WSL or WINE when using Redbean 2.x, they may be fixed by disabling binfmt_misc:
sudo sh -c 'echo -1 >/proc/sys/fs/binfmt_misc/status'
Since we used the ape-no-modify-self.o
bootloader (rather than
ape.o
) your executable will not modify itself when it's run. What
it'll instead do, is extract a 4kb program to ${TMPDIR:-${HOME:-.}}
that maps your program into memory without needing to copy it. It's
possible to install the APE loader systemwide as follows.
# System-Wide APE Install
# for Linux, Darwin, and BSDs
# 1. Copies APE Loader to /usr/bin/ape
# 2. Registers w/ binfmt_misc too if Linux
ape/apeinstall.sh
# System-Wide APE Uninstall
# for Linux, Darwin, and BSDs
ape/apeuninstall.sh
It's also possible to convert APE binaries into the system-local format
by using the --assimilate
flag. Please note that if binfmt_misc is in
play, you'll need to unregister it temporarily before doing this, since
the assimilate feature is part of the shell script header.
$ file hello.com
hello.com: DOS/MBR boot sector
./hello.com --assimilate
$ file hello.com
hello.com: ELF 64-bit LSB executable
Now that you're up and running with Cosmopolitan Libc and APE, here's some of the most important troubleshooting tools APE offers that you should know, in case you encounter any issues:
./hello.com --strace # log system calls to stderr
./hello.com --ftrace # log function calls to stderr
Do you love tiny binaries? If so, you may not be happy with Cosmo adding heavyweight features like tracing to your binaries by default. In that case, you may want to consider using our build system:
make -j8 MODE=tiny
Which will cause programs such as hello.com
and life.com
to shrink
from 60kb in size to about 16kb. There's also a prebuilt amalgamation
online https://justine.lol/cosmopolitan/cosmopolitan-tiny.zip hosted
on our download page https://justine.lol/cosmopolitan/download.html.
MacOS
If you're developing on MacOS you can install the GNU compiler collection for x86_64-elf via homebrew:
brew install x86_64-elf-gcc
Then in the above scripts just replace gcc
and objcopy
with
x86_64-elf-gcc
and x86_64-elf-objcopy
to compile your APE binary.
Windows
If you're developing on Windows then you need to download an x86_64-pc-linux-gnu toolchain beforehand. See the Compiling on Windows tutorial. It's needed because the ELF object format is what makes universal binaries possible.
Cosmopolitan officially only builds on Linux. However, one highly experimental (and currently broken) thing you could try, is building the entire cosmo repository from source using the cross9 toolchain.
mkdir -p o/third_party
rm -rf o/third_party/gcc
wget https://justine.lol/linux-compiler-on-windows/cross9.zip
unzip cross9.zip
mv cross9 o/third_party/gcc
build/bootstrap/make.com
Source Builds
Cosmopolitan can be compiled from source on any Linux distro. First, you need to download or clone the repository.
wget https://justine.lol/cosmopolitan/cosmopolitan.tar.gz
tar xf cosmopolitan.tar.gz # see releases page
cd cosmopolitan
This will build the entire repository and run all the tests:
build/bootstrap/make.com -j16
o//examples/hello.com
find o -name \*.com | xargs ls -rShal | less
If you get an error running make.com then it's probably because you have
WINE installed to binfmt_misc
. You can fix that by installing the the
APE loader as an interpreter. It'll improve build performance too!
ape/apeinstall.sh
Since the Cosmopolitan repository is very large, you might only want to build a particular thing. Cosmopolitan's build config does a good job at having minimal deterministic builds. For example, if you wanted to build only hello.com then you could do that as follows:
build/bootstrap/make.com -j16 o//examples/hello.com
Sometimes it's desirable to build a subset of targets, without having to list out each individual one. You can do that by asking make to build a directory name. For example, if you wanted to build only the targets and subtargets of the chibicc package including its tests, you would say:
build/bootstrap/make.com -j16 o//third_party/chibicc
o//third_party/chibicc/chibicc.com --help
Cosmopolitan provides a variety of build modes. For example, if you want really tiny binaries (as small as 12kb in size) then you'd say:
build/bootstrap/make.com -j16 MODE=tiny
Here's some other build modes you can try:
build/bootstrap/make.com -j16 MODE=dbg # asan + ubsan + debug
build/bootstrap/make.com -j16 MODE=asan # production memory safety
build/bootstrap/make.com -j16 MODE=opt # -march=native optimizations
build/bootstrap/make.com -j16 MODE=rel # traditional release binaries
build/bootstrap/make.com -j16 MODE=optlinux # optimal linux-only performance
build/bootstrap/make.com -j16 MODE=tinylinux # tiniest linux-only 4kb binaries
For further details, see //build/config.mk.
GDB
Here's the recommended ~/.gdbinit
config:
set host-charset UTF-8
set target-charset UTF-8
set target-wide-charset UTF-8
set osabi none
set complaints 0
set confirm off
set history save on
set history filename ~/.gdb_history
define asm
layout asm
layout reg
end
define src
layout src
layout reg
end
src
You normally run the .com.dbg
file under gdb. If you need to debug the
.com
file itself, then you can load the debug symbols independently as
gdb foo.com -ex 'add-symbol-file foo.com.dbg 0x401000'
Support Vector
Platform | Min Version | Circa |
---|---|---|
AMD | K8 Venus | 2005 |
Intel | Core | 2006 |
Windows | Vista | 2006 |
Linux | 2.6.18 | 2007 |
Mac OS X | 15.6 | 2018 |
FreeBSD | 13 | 2020 |
OpenBSD | 6.4 | 2018 |
NetBSD | 9.2 | 2021 |
Special Thanks
Funding for this project is crowdsourced using GitHub Sponsors and Patreon. Your support is what makes this project possible. Thank you! We'd also like to give special thanks to the following individuals:
For publicly sponsoring our work at the highest tier.