Bash loadable module that embeds python as builtin command bashpy, taking python code as first argument.
It's not very useful but merely a proof of concept. As it doesn't provide the python context any access to bash internals or even support passing it variables.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
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The Embedding Python example here: https://docs.python.org/3/extending/embedding.html#very-high-level-embedding
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Bash examples/loadables/cat.c https://github.com/bminor/bash/blob/master/examples/loadables/cat.c
I wanted to try building a loadable module after I got notion about the loadable module support in Bash by this video about Suidbash https://www.youtube.com/watch?v=-wGtxJ8opa8.
There already exist loadable modules for other languages as:
As I found out after some research, but I could not find any python equivalent.
Exact requirements TBD, but essentially:
- build-essentials
- python dev (tested with: python 3.8.0 from pyenv)
- bash sourcecode (tested with: bash 4.3 from github)
- editing of some hardcoded paths in Makefile
To build the loadable module we need bash sources.
The getbashsrc.sh script downloads and configures bash 5.0, update it first to match the bash --version.
./getbashsrc.sh
Python needs to be built with --enable-shared, this is how to do it using pyenv.
PYTHON_CONFIGURE_OPTS="--enable-shared" pyenv install 3.8.0
Make sure you have pyenv installed/cloned to ~/.pyenv (or symlink it there or change paths in Makefile).
make -C bashpy
make -C bashpy test
See examples/*.sh for some info on how to invoke bashpy from a script.
Build and test bash loadable git/bash/examples/loadables/hello (a "hello world" example).
### build
./configure
make pathnames.h
make -C examples/loadables hello
### enable
cd examples/loadables
enable -f $PWD/hello hello
### run
hello
Hello world
### unload
enable -d $PWD/hello hello
hello
<error>
Build and run python embedded example examples/embedded-python-today/.
cd examples/embedded-python-today/
# Edit the Makefile to point to the correct python.
make
./today
- Support passing/getting variables.
- Support stdin (see
git/bash/examples/loadable/cat.c). - Pass the python code as file.
- Support calling functions.
- Make it easier to write code inline compared to examples.
- Luabash, for ideas on how to increase the usability.
- Bash, for what would my life be without it. Also great docs and examples!
- Ian Pudney and LiveOverflow for inspiring me to try and build a bash loadable builtin.
GPLv3, See the file COPYING
Copyright (C) 2019 Emil Lind - <github@sys.nu>
This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
You should have received a copy of the GNU General Public License along with this program. If not, see https://www.gnu.org/licenses/.