virt-pack

virt-pack is a tool that uses bear to intercept your build commands, and detects missing system libraries (via pkg-config) and installs them using your system's package manager. It's especially useful for C/C++ projects with messy dependencies.

Note: This version currently supports only Makefile and CMakeLists.txt-based projects. Support for other build systems like Cargo is a work in progress.

Installation

This version of virt-pack currently only supports Debian-based systems as it uses the apt and apt-file tools to install missing libraries. Since the tool uses bear, run the following command in your terminal to install it

sudo apt install bear

After this, we can run the following commands in an empty directory to install virt-pack

git clone https://github.com/ava-xmas/virt-pack-ubuntu.git
cd virt-pack-ubuntu
chmod +x install.sh
./install.sh

How to use

After installation, we first need to download the package mapping database by running the following command:

virt-pack update-db

Then, move into your project directory with missing dependencies and run the following command:

For Makefile-based projects

virt-pack make <env-name>

For CmakeLists.txt-based projects

mkdir build
cd build
virt-pack cmake <env-name>

Keep in mind that the dependencies should be included in the Makefile / CmakeLists.txt. An example Makefile is provided below. Also, an events.json file will be generated in the directory where the command is run from. After virt-pack exits successfully, it is safe to delete that file. For more options you can pass --help parameter.

To remove the installed packages when you don't need them anymore, run the following command:

virt-pack remove <env-name>

This will only remove the packages that were installed using virt-pack. The libraries that you had before will not be removed.

Example

Here's a minimal Makefile that virt-pack can work with:

CC = gcc
TARGET = virt-pack-test

# Replace this with the libraries you want to use
LIB_NAME = <library-name>
PKG := pkg-config --cflags --libs $(LIB_NAME)

all: $(TARGET)

$(TARGET): main.c
	$(CC) main.c -o $(TARGET) $(shell $(PKG))

clean:
	rm -f $(TARGET)

See the test/Makefile for a sample project that uses virt-pack.

Working

Database of Libraries

virt-pack maintains a local database (virt-pack-db.json) that maps library names (from .pc files) to their corresponding Debian packages. To keep this mapping up to date, it uses a script that downloads Debian's Contents-amd64.gz, a list of all files in Debian packages.

virt-pack make command

Parsing bear intercept

Upon running the make command, bear intercept -- make is run, which intercepts calls, including the ones made to pkg-config. These events are logged in <env-name>-events.json.

Resolving system libraries

The system libraries mentioned in the pkg-config calls (.pc files) are logged in libs-from-intercept.json. Then, the existance of each library on your system is checked using pkg-config --exists [library-name]. The missing libraries are logged to missing-libs.json

Installing required packages

The package name for the missing .pc files is found using the database. Then, sudo apt install [package-name] is run to install the packages. These are also logged to <env-name>-installed.json.

Uninstalling previously installed packages

<env-name>-installed.json file is used to uninstall the packages using sudo apt remove -y [package-name]. After successful uninstallation, the <env-name>-installed.json file is also removed.