reloc-cpp

CMake/C++ library to get the installation prefix of a shared library in a relocatable way.

In a nutshell, it permits to avoid the need to hardcode the location of CMAKE_INSTALL_PREFIX in a shared library if you need it to localize other resources installed with the package. This permits to easily move the installation prefix in a location different from CMAKE_INSTALL_PREFIX after the installation (i.e. making it a relocatable installation), as long as the library is compiled as shared. This is useful when the C++ shared library is packaged in package managers that create the package with a given CMAKE_INSTALL_PREFIX and install it with a different prefix, such as conda, vcpkg or conan.

In the case that the library is compiled as static, reloc-cpp will fall back to hardcode CMAKE_INSTALL_PREFIX in the library.

reloc-cpp requires the use of C++ 17 or any later version.

Installation

FetchContent

include(FetchContent)
FetchContent_Declare(
  reloc-cpp
  GIT_REPOSITORY https://github.com/ami-iit/reloc-cpp.git
  GIT_TAG        v0.1.0
)

FetchContent_MakeAvailable(reloc-cpp)

Usage

In your CMake build system you can use reloc-cpp as:

add_library(yourLibrary)

# ...

reloc_cpp_generate(yourLibrary
                   GENERATED_HEADER ${CMAKE_CURRENT_BINARY_DIR}/yourLibrary_getInstallPrefix.h
                   GENERATED_FUNCTION yourLibrary::getInstallPrefix)

then, you can use it in C++ as:

#include <yourLibrary_getInstallationPrefix.h>

// This return the value corresponding to CMAKE_INSTALL_PREFIX
std::string installPrefix = yourLibrary::getInstallPrefix().value();

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

References

References that were useful as inspiration when developing reloc-cpp:

• "Helping C/C++ Packages be Relocatable" presentation
• Resourceful: Techniques for installing and accessing resource files using C++ and Python.
• "Qt is relocatable" blog post
• binreloc: Library for creating relocatable software

Resources that could be useful as an alternative to reloc-cpp:

• cmrc: A Resource Compiler in a Single CMake Script

License

BSD-3-Clause