Add to the CMakeLists.txt of the main project, after its project() line (requires cmake 3.14 or later):
include(FetchContent)
set(GITACHE_PACKAGES libcwd_r) # List of requested packages (example).
FetchContent_Declare(
gitache
GIT_REPOSITORY "https://github.com/CarloWood/gitache.git"
GIT_TAG "stable"
)
FetchContent_MakeAvailable(gitache)
Where, if you're paranoid, you should replace stable with its
git commit sha1 (from the stable branch, the master branch might
be unstable). Both, stable and master will cause a git fetch
every time the project is configured to see if the project was updated,
so for a large project please just use the sha1 of stable (or master,
if that works at that moment).
GITACHE_PACKAGES must be set to the list of packages that need
to be downloaded, configured and compiled (if not already in the cache).
Alternatively you can add gitache as a submodule to the root of your project and replace all of the above with,
set(GITACHE_PACKAGES libcwd_r) # List of requested packages (example).
include(gitache/gateway.cmake)
That will not update gitache automatically but simply use whatever you have checked out.
Each package listed in GITACHE_PACKAGES must have a configuration
file in the cmake cache variable GITACHE_CONFIGS_DIR, the default
being ${CMAKE_SOURCE_DIR}/cmake/gitache-configs, with the name
<package>.cmake. See https://github.com/CarloWood/gitache-core for
a description of the contents.
The minimum cmake version required is 3.14.
Furthermore, the user must have the environment variable
GITACHE_ROOT set to a writable directory, or gitache will do
nothing except print the message:
-- Environment variable GITACHE_ROOT is not set: gitache disabled.
Finally, the user must know what they are doing: warn them not
to set LD_LIBRARY_PATH pointing to a library that is also installed
by gitache. This wouldn't work since the project is linked against
the version compiled by gitache, so at runtime -rpath must be honored
and (unfortunately?) LD_LIBRARY_PATH has a higher precedence.
As an alternative you could add the following line to your project (assuming you're creating an executable and your linker honors that flag):
set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--disable-new-dtags")
after which the -rpath will get precedence so the value of LD_LIBRARY_PATH
in the users environment becomes unimportant.
See the README.md of https://github.com/CarloWood/gitache-core