pnut

It's an ongoing project: https://github.com/udem-dlteam/pnut See also pnut.sh, but the server seems to be down at the moment.

That sounds like pnut: https://github.com/udem-dlteam/pnut

Related: pnut.sh https://github.com/udem-dlteam/pnut just released. It’s a self-compiling C->POSIX shell transpiler that outputs readable shell, aimed at live-bootstrap and reproducible build chains. The shell edition is auditable and can bootstrap a native compiler from just POSIX sh + coreutils. Very much in the spirit of stage0 / compile-from-nothing work.

Author here, > assuming the resulting shell script is as inscrutably as binary executable It's quite the opposite, pnut generates shell code that's close to the original C code to make it easy to audit the code. A useful way to see pnut is as a tool that rewrites C code to POSIX shell, without significantly changing the structure. This means that even if GCC is required for the initial compilation of pnut (GCC compiles pnut, then pnut compiles itself and we get the pnut-sh.sh script), the script can be "sanitized" from trusting trust attacks by simply comparing the script to the C code and making sure GCC hasn't introduced any malicious code. Page 10 of the SLE24 presentation has a tombstone diagram showing the compilation steps to go from pnut's C code to a GCC binary: https://github.com/udem-dlteam/pnut/blob/main/doc/presentati...

Hi! One of the original author of Ribbit here, glad to see it is still getting attention. Léonard and Marc took the project much further than I imagined. As a fun fact, the project started as a riff of Justine Tunney's famous https://justine.lol/sectorlisp/. For the interested, my new favorite project from Marc's team is https://github.com/udem-dlteam/pnut

There seems to be libc in the repo but many functions are TODO https://github.com/udem-dlteam/pnut/tree/main/portable_libc Otherwise the builtins seems to be here https://github.com/udem-dlteam/pnut/blob/main/runtime.sh FYI all your functions are not "C functions", but rather POSIX functions. I did not expect it to be complete, but it's still impressive for what it is.

One of the example we include is a base64 encoder/decoder: https://github.com/udem-dlteam/pnut/blob/main/examples/compiled/base64.sh It doesn't support NULs as you pointed out, but it's interesting to see similarities between your implementation and the one generated by Pnut. Because we use `read -r`, we haven't tested reading binary files. Fortunately, the shell's `printf` function can emit all 256 characters so Pnut can at least output binary files. This makes it possible for Pnut to have a x86 backend for the use of reproducible builds. Regarding the use of `read`, one constraint we set ourselves when writing Pnut is to not use any external utilities, including those that are specified by the POSIX standard (other than `read` and `printf`). This maximizes portability of the code generated by Pnut and is enough for the reproducible b