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Exec Plugin🔗

The Exec plugin for vAccel implements a backend to call functions from external libraries using vAccel operations.

Warning

This plugins enables users to call functions from arbitrary libraries. Use it only on environments where the users are trusted.

Supported operations🔗

Installing the plugin🔗

The plugin comes bundled with the core vAccel installation. Find out more on how to install vAccel at the Installation page.

Usage🔗

To specify Exec plugin as the selected plugin for vAccel execution:

export VACCEL_PLUGINS=libvaccel-exec.so

Ensure vAccel and the Exec plugin libraries are in the library search paths before trying to use the plugin.

Running an example🔗

Export the necessary variables for the plugin:

export VACCEL_PLUGINS=libvaccel-exec.so
# Optionally, for verbose output
export VACCEL_LOG_LEVEL=4

Assuming pkg-config is available, you can call mytestfunc from the provided libmytestlib.so with:

$ exec_with_res "$(pkg-config --variable=libdir vaccel)/libmytestlib.so"
2025.04.15-19:37:37.77 - <debug> Initializing vAccel
2025.04.15-19:37:37.77 - <info> vAccel 0.6.1-194-19056528
2025.04.15-19:37:37.77 - <debug> Config:
2025.04.15-19:37:37.77 - <debug>   plugins = libvaccel-exec.so
2025.04.15-19:37:37.77 - <debug>   log_level = debug
2025.04.15-19:37:37.77 - <debug>   log_file = (null)
2025.04.15-19:37:37.77 - <debug>   profiling_enabled = false
2025.04.15-19:37:37.77 - <debug>   version_ignore = false
2025.04.15-19:37:37.77 - <debug> Created top-level rundir: /run/user/1002/vaccel/DYBt4h
2025.04.15-19:37:37.77 - <info> Registered plugin exec 0.6.1-194-19056528
2025.04.15-19:37:37.77 - <debug> Registered op noop from plugin exec
2025.04.15-19:37:37.77 - <debug> Registered op exec from plugin exec
2025.04.15-19:37:37.77 - <debug> Registered op exec_with_resource from plugin exec
2025.04.15-19:37:37.77 - <debug> Loaded plugin exec from libvaccel-exec.so
2025.04.15-19:37:37.77 - <warn> Path does not seem to have a `<prefix>://`
2025.04.15-19:37:37.77 - <warn> Assuming /usr/local/lib/x86_64-linux-gnu/libmytestlib.so is a local path
2025.04.15-19:37:37.77 - <debug> Initialized resource 1
2025.04.15-19:37:37.77 - <debug> New rundir for session 1: /run/user/1002/vaccel/DYBt4h/session.1
2025.04.15-19:37:37.77 - <debug> Initialized session 1
Initialized session with id: 1
2025.04.15-19:37:37.77 - <debug> New rundir for resource 1: /run/user/1002/vaccel/DYBt4h/resource.1
2025.04.15-19:37:37.77 - <debug> session:1 Registered resource 1
2025.04.15-19:37:37.77 - <debug> New rundir for resource 2: /run/user/1002/vaccel/DYBt4h/resource.2
2025.04.15-19:37:37.77 - <debug> Persisting file lib.so to /run/user/1002/vaccel/DYBt4h/resource.2/lib.so
2025.04.15-19:37:37.77 - <debug> Initialized resource 2
2025.04.15-19:37:37.77 - <debug> session:1 Registered resource 2
2025.04.15-19:37:37.77 - <debug> session:1 Looking for plugin implementing exec with resource
2025.04.15-19:37:37.77 - <debug> Returning func from hint plugin exec
2025.04.15-19:37:37.77 - <debug> Found implementation in exec plugin
2025.04.15-19:37:37.77 - <debug> [exec_with_resource] session:1 Calling exec_with_resource
2025.04.15-19:37:37.77 - <debug> [exec_with_resource] Number of libraries: 1
2025.04.15-19:37:37.77 - <debug> [exec_with_resource] Library: /usr/local/lib/x86_64-linux-gnu/libmytestlib.so
2025.04.15-19:37:37.77 - <debug> [exec_with_resource] Symbol: mytestfunc
2025.04.15-19:37:37.77 - <debug> [exec_with_resource] read[0].size: 4
2025.04.15-19:37:37.77 - <debug> [exec_with_resource] read[0].argtype: 42
2025.04.15-19:37:37.77 - <debug> [exec_with_resource] write[0].size: 4
2025.04.15-19:37:37.77 - <debug> [exec_with_resource] write[0].argtype: 42
I got nr_in: 1, nr_out: 1
I got input: 10
Will return output: 20
output1: 20
2025.04.15-19:37:37.77 - <debug> session:1 Looking for plugin implementing exec with resource
2025.04.15-19:37:37.77 - <debug> Returning func from hint plugin exec
2025.04.15-19:37:37.77 - <debug> Found implementation in exec plugin
2025.04.15-19:37:37.77 - <debug> [exec_with_resource] session:1 Calling exec_with_resource
2025.04.15-19:37:37.77 - <debug> [exec_with_resource] Number of libraries: 1
2025.04.15-19:37:37.77 - <debug> [exec_with_resource] Library: /run/user/1002/vaccel/DYBt4h/resource.2/lib.so
2025.04.15-19:37:37.77 - <debug> [exec_with_resource] Symbol: mytestfunc
2025.04.15-19:37:37.77 - <debug> [exec_with_resource] read[0].size: 4
2025.04.15-19:37:37.77 - <debug> [exec_with_resource] read[0].argtype: 0
2025.04.15-19:37:37.77 - <debug> [exec_with_resource] write[0].size: 4
2025.04.15-19:37:37.77 - <debug> [exec_with_resource] write[0].argtype: 0
I got nr_in: 1, nr_out: 1
I got input: 10
Will return output: 20
output2: 20
2025.04.15-19:37:37.77 - <debug> session:1 Unregistered resource 2
2025.04.15-19:37:37.77 - <debug> Removing file /run/user/1002/vaccel/DYBt4h/resource.2/lib.so
2025.04.15-19:37:37.77 - <debug> Released resource 2
2025.04.15-19:37:37.77 - <debug> session:1 Unregistered resource 1
2025.04.15-19:37:37.77 - <debug> Released session 1
2025.04.15-19:37:37.77 - <debug> Released resource 1
2025.04.15-19:37:37.77 - <debug> Cleaning up vAccel
2025.04.15-19:37:37.77 - <debug> Cleaning up sessions
2025.04.15-19:37:37.77 - <debug> Cleaning up resources
2025.04.15-19:37:37.77 - <debug> Cleaning up plugins
2025.04.15-19:37:37.77 - <debug> Unregistered plugin exec