diff options
Diffstat (limited to 'src')
| -rwxr-xr-x | src/cmake/macros/FindFilesystem.cmake | 243 | ||||
| -rw-r--r-- | src/common/CMakeLists.txt | 1 |
2 files changed, 244 insertions, 0 deletions
diff --git a/src/cmake/macros/FindFilesystem.cmake b/src/cmake/macros/FindFilesystem.cmake new file mode 100755 index 0000000000..87809b8608 --- /dev/null +++ b/src/cmake/macros/FindFilesystem.cmake @@ -0,0 +1,243 @@ +# Distributed under the OSI-approved BSD 3-Clause License. See accompanying +# file Copyright.txt or https://cmake.org/licensing for details. +# +# Copied from: +# https://github.com/lethal-guitar/RigelEngine/blob/master/cmake/Modules/FindFilesystem.cmake +# +# Which is copied from: +# https://github.com/vector-of-bool/CMakeCM/blob/master/modules/FindFilesystem.cmake + +#[=======================================================================[.rst: + +FindFilesystem +############## + +This module supports the C++17 standard library's filesystem utilities. Use the +:imp-target:`std::filesystem` imported target to + +Options +******* + +The ``COMPONENTS`` argument to this module supports the following values: + +.. find-component:: Experimental + :name: fs.Experimental + + Allows the module to find the "experimental" Filesystem TS version of the + Filesystem library. This is the library that should be used with the + ``std::experimental::filesystem`` namespace. + +.. find-component:: Final + :name: fs.Final + + Finds the final C++17 standard version of the filesystem library. + +If no components are provided, behaves as if the +:find-component:`fs.Final` component was specified. + +If both :find-component:`fs.Experimental` and :find-component:`fs.Final` are +provided, first looks for ``Final``, and falls back to ``Experimental`` in case +of failure. If ``Final`` is found, :imp-target:`std::filesystem` and all +:ref:`variables <fs.variables>` will refer to the ``Final`` version. + +Imported Targets +**************** + +.. imp-target:: std::filesystem + + The ``std::filesystem`` imported target is defined when any requested + version of the C++ filesystem library has been found, whether it is + *Experimental* or *Final*. + + If no version of the filesystem library is available, this target will not + be defined. + + .. note:: + This target has ``cxx_std_17`` as an ``INTERFACE`` + :ref:`compile language standard feature <req-lang-standards>`. Linking + to this target will automatically enable C++17 if no later standard + version is already required on the linking target. + +.. _fs.variables: + +Variables +********* + +.. variable:: CXX_FILESYSTEM_IS_EXPERIMENTAL + + Set to ``TRUE`` when the :find-component:`fs.Experimental` version of C++ + filesystem library was found, otherwise ``FALSE``. + +.. variable:: CXX_FILESYSTEM_HAVE_FS + + Set to ``TRUE`` when a filesystem header was found. + +.. variable:: CXX_FILESYSTEM_HEADER + + Set to either ``filesystem`` or ``experimental/filesystem`` depending on + whether :find-component:`fs.Final` or :find-component:`fs.Experimental` was + found. + +.. variable:: CXX_FILESYSTEM_NAMESPACE + + Set to either ``std::filesystem`` or ``std::experimental::filesystem`` + depending on whether :find-component:`fs.Final` or + :find-component:`fs.Experimental` was found. + +Examples +******** + +Using `find_package(Filesystem)` with no component arguments: + +.. code-block:: cmake + + find_package(Filesystem REQUIRED) + + add_executable(my-program main.cpp) + target_link_libraries(my-program PRIVATE std::filesystem) + +#]=======================================================================] + +if(TARGET std::filesystem) + # This module has already been processed. Don't do it again. + return() +endif() + +cmake_policy(PUSH) +if(POLICY CMP0067) + # pass CMAKE_CXX_STANDARD to check_cxx_source_compiles() + # has to appear before including CheckCXXSourceCompiles module + cmake_policy(SET CMP0067 NEW) +endif() + +include(CMakePushCheckState) +include(CheckIncludeFileCXX) +include(CheckCXXSourceCompiles) + +cmake_push_check_state() + +set(CMAKE_REQUIRED_QUIET ${Filesystem_FIND_QUIETLY}) + +# All of our tests required C++17 or later +# But AC already sets this in ConfigureBaseTargets.cmake +# set(CMAKE_CXX_STANDARD 17) + +# Normalize and check the component list we were given +set(want_components ${Filesystem_FIND_COMPONENTS}) +if(Filesystem_FIND_COMPONENTS STREQUAL "") + set(want_components Final) +endif() + +# Warn on any unrecognized components +set(extra_components ${want_components}) +list(REMOVE_ITEM extra_components Final Experimental) +foreach(component IN LISTS extra_components) + message(WARNING "Extraneous find_package component for Filesystem: ${component}") +endforeach() + +# Detect which of Experimental and Final we should look for +set(find_experimental TRUE) +set(find_final TRUE) +if(NOT "Final" IN_LIST want_components) + set(find_final FALSE) +endif() +if(NOT "Experimental" IN_LIST want_components) + set(find_experimental FALSE) +endif() + +if(find_final) + check_include_file_cxx("filesystem" _CXX_FILESYSTEM_HAVE_HEADER) + mark_as_advanced(_CXX_FILESYSTEM_HAVE_HEADER) + if(_CXX_FILESYSTEM_HAVE_HEADER) + # We found the non-experimental header. Don't bother looking for the + # experimental one. + set(find_experimental FALSE) + endif() +else() + set(_CXX_FILESYSTEM_HAVE_HEADER FALSE) +endif() + +if(find_experimental) + check_include_file_cxx("experimental/filesystem" _CXX_FILESYSTEM_HAVE_EXPERIMENTAL_HEADER) + mark_as_advanced(_CXX_FILESYSTEM_HAVE_EXPERIMENTAL_HEADER) +else() + set(_CXX_FILESYSTEM_HAVE_EXPERIMENTAL_HEADER FALSE) +endif() + +if(_CXX_FILESYSTEM_HAVE_HEADER) + set(_have_fs TRUE) + set(_fs_header filesystem) + set(_fs_namespace std::filesystem) +elseif(_CXX_FILESYSTEM_HAVE_EXPERIMENTAL_HEADER) + set(_have_fs TRUE) + set(_fs_header experimental/filesystem) + set(_fs_namespace std::experimental::filesystem) +else() + set(_have_fs FALSE) +endif() + +set(CXX_FILESYSTEM_HAVE_FS ${_have_fs} CACHE BOOL "TRUE if we have the C++ filesystem headers") +set(CXX_FILESYSTEM_HEADER ${_fs_header} CACHE STRING "The header that should be included to obtain the filesystem APIs") +set(CXX_FILESYSTEM_NAMESPACE ${_fs_namespace} CACHE STRING "The C++ namespace that contains the filesystem APIs") + +set(_found FALSE) + +if(CXX_FILESYSTEM_HAVE_FS) + # We have some filesystem library available. Do link checks + string(CONFIGURE [[ + #include <@CXX_FILESYSTEM_HEADER@> + + int main() { + auto cwd = @CXX_FILESYSTEM_NAMESPACE@::current_path(); + return static_cast<int>(cwd.string().size()); + } + ]] code @ONLY) + + # Try to compile a simple filesystem program without any linker flags + check_cxx_source_compiles("${code}" CXX_FILESYSTEM_NO_LINK_NEEDED) + + set(can_link ${CXX_FILESYSTEM_NO_LINK_NEEDED}) + + if(NOT CXX_FILESYSTEM_NO_LINK_NEEDED) + set(prev_libraries ${CMAKE_REQUIRED_LIBRARIES}) + # Add the libstdc++ flag + set(CMAKE_REQUIRED_LIBRARIES ${prev_libraries} -lstdc++fs) + check_cxx_source_compiles("${code}" CXX_FILESYSTEM_STDCPPFS_NEEDED) + set(can_link ${CXX_FILESYSTEM_STDCPPFS_NEEDED}) + if(NOT CXX_FILESYSTEM_STDCPPFS_NEEDED) + # Try the libc++ flag + set(CMAKE_REQUIRED_LIBRARIES ${prev_libraries} -lc++fs) + check_cxx_source_compiles("${code}" CXX_FILESYSTEM_CPPFS_NEEDED) + set(can_link ${CXX_FILESYSTEM_CPPFS_NEEDED}) + endif() + endif() + + if(can_link) + add_library(std::filesystem INTERFACE IMPORTED) + target_compile_features(std::filesystem INTERFACE cxx_std_17) + set(_found TRUE) + if(CXX_FILESYSTEM_NO_LINK_NEEDED) + # on certain linux distros we have a version of libstdc++ which has the final code for c++17 fs in the + # libstdc++.so.*. BUT when compiling with g++ < 9, we MUST still link with libstdc++fs.a + # libc++ should not suffer from this issue, so, in theory we should be fine with only checking for + # GCC's libstdc++ + if((CMAKE_CXX_COMPILER_ID MATCHES "GNU") AND (CMAKE_CXX_COMPILER_VERSION VERSION_LESS "9.0.0")) + target_link_libraries(std::filesystem INTERFACE -lstdc++fs) + endif() + elseif(CXX_FILESYSTEM_STDCPPFS_NEEDED) + target_link_libraries(std::filesystem INTERFACE -lstdc++fs) + elseif(CXX_FILESYSTEM_CPPFS_NEEDED) + target_link_libraries(std::filesystem INTERFACE -lc++fs) + endif() + endif() +endif() + +cmake_pop_check_state() + +set(Filesystem_FOUND ${_found} CACHE BOOL "TRUE if we can compile and link a program using std::filesystem" FORCE) + +if(Filesystem_FIND_REQUIRED AND NOT Filesystem_FOUND) + message(FATAL_ERROR "Cannot Compile simple program using std::filesystem") +endif() + +cmake_policy(POP) diff --git a/src/common/CMakeLists.txt b/src/common/CMakeLists.txt index 704cdc8bba..d8205e2412 100644 --- a/src/common/CMakeLists.txt +++ b/src/common/CMakeLists.txt @@ -61,6 +61,7 @@ target_link_libraries(common openssl threads jemalloc + stdfs fmt) set_target_properties(common |