This repository contains CMake files for Wei Dai's Crypto (https://github.com/weidai11/cryptopp) for those who use the library in Modern CMake projects.
See this announcement from crypto maintainers.
The emphasis on Modern here is very important. In 2022, we have some really good solutions to many of the build problems developers used to waste a lot of time on. CMake in particular has made so much progress to become one of the most widely used build systems for C . But, we're not talking about CMake 2.x here. We're talking about CMake 3.11 and maybe even CMake 3.24 .
For more details on this topic, see down below...
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Can you support an older version of CMake? You really don't need 3.21...
No.
This is an opinionated fork with the main purpose being to stay always on a recent version of CMake. We believe that the build system should be the latest unlike compilers and Operating Systems. If you want to stay on old versions, please take a look at the old repo.
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Can you fix the shared library build? I really like DLLs...
Me too, but No.
Crypto does not properly export symbols and manage visibility. You can request this feature from the crypto project maintainers. The old DLL build was only for FIPS version, with limited symbol exports. That version is going end-of-life and there is no point from supporting it here.
If you love DLLs, you can make a Wrapper DLL as explained on crypto wiki.
The CMakeLists.txt in this project are already built for shared and static builds, but the shared build is locked until crypto is ready for it.
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Why did you change XXX? It used to work like YYY before...
I don't know.
I use crypto in my project, and I use it in a way that I learnt and improved over time through experience, extensive reading of other peoples' experiences, and sticking as close as possible to modern cmake practices. I'm open to new ways and suggestions, especially if they come via a tracked issue, a rationale and a pull request. If you have a valid use case, please document it in an issue and let's find someone to help make it happen for you. It's Open Source 😃
This project releases track the crypto releases. In other words, every time a new release of crypto happens, this project gets updated to take into account changes in source files, compiler options etc, and will see a new release with the same number than crypto .
At times, bug fixes in this project will happen before a new crypto release
is published. When a certain number of fixes have been added, and depending on
the criticality of the defects, an additional release tag may be made. These
patch tags will never introduce any additional changes in crypto
itself.
Main release tags will have the format: CRYPTOPP_M_m_p
, while patch tags
will have the format CRYPTOPP_M_m_p_f
, where M.m.p
represents the crypto
version and f
is a suffix number incremented each time a patch tag is
created. Patch tags will keep the same crypto
version as the main release
tag.
As always, if you want to get the latest and greatest, always track the master branch.
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Get this project using your favorite method (clone as submodule, get with FetchContent, get with CPM...)
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In your master CMakeLists.txt, add the following:
add_subdirectory(xxxx) # where xxx is the location where you put the cryptopp-cmake files
That's pretty much it. You'll be able to link against
cryptopp
or the scoped aliascryptopp::cryptopp
and have cmake handle everything else for you.
An example is located in the test/standard-cpm directory.
Certain users would prefer to have a fully disconnected project, and in such scenario both the crypto source package and the cryptopp-cmake source package would be pre-downloaded and then unpacked somewhere.
You would still need to add cryptopp-cmake as a subdirectory in your master
CMakeLists.txt
, and you can set it up in such a way to use your local copy of
crypto via the option CRYPTOPP_SOURCES
. Just set that option in the cmake
command line or in your CMakeLists.txt to point to the crypto source
directory. The rest will be taken care of for you.
If you want to test the bleeding edge of crypto with cmake, simply set the
option CRYPTOPP_USE_MASTER_BRANCH
in your CMakeLists.txt or the cmake command
line and as usual, add the cryptopp-cmake as a subdirectory.
There are many other ways to use this project, including by directly picking the files you need and adding them to your own project, by getting the package via conan, etc... Take some time to read the source code, and make suggestions if you need a new usage scenario via a new issue.
Have a look at Installing CMake from the online 'Modern CMake' book, to see a recent snapshot of which version of CMake is being installed by default on Linux distributions.
And more than that, it's so easy to install a modern version of CMake on Linux/MacOS/Windows, and many other OSes.
Looking at the release notes of CMake versions from 3.0 till now, a minimum version requirement of 3.21 is a good starting point. That release brings in particular presets and some nice quality of life features that will make the maintenance and the use of this project much simpler and pleasant. After all, there is no justification for doing free Open Source without pleasure 😃