copy directory to another from add_custom_target - cmake

I have this target code:
add_custom_target (
dist
COMMAND ${CMAKE_COMMAND} -E make_directory "${PROJECT_BINARY_DIR}/${PROJECT_NAME}-${PROJECT_VERSION}"
COMMAND ${CMAKE_COMMAND} -E copy ${PROJECT_SOURCE_DIR}/CMakeLists.txt ${PROJECT_BINARY_DIR}/${PROJECT_NAME}-${PROJECT_VERSION}
COMMAND ${CMAKE_COMMAND} -E copy ${PROJECT_SOURCE_DIR}/src ${PROJECT_BINARY_DIR}/${PROJECT_NAME}-${PROJECT_VERSION}
COMMAND ${CMAKE_COMMAND} -E copy ${PROJECT_SOURCE_DIR}/data ${PROJECT_BINARY_DIR}/${PROJECT_NAME}-${PROJECT_VERSION}
COMMAND ${CMAKE_COMMAND} -E copy ${PROJECT_SOURCE_DIR}/po ${PROJECT_BINARY_DIR}/${PROJECT_NAME}-${PROJECT_VERSION}
COMMAND ${7Z} a -t7z ${PACKER_PACKAGE_FILE_NAME_EXT} ${PROJECT_BINARY_DIR}/${PROJECT_NAME}-${PROJECT_VERSION}
COMMAND ${CMAKE_COMMAND} -E remove_directory "${PROJECT_BINARY_DIR}/${PROJECT_NAME}-${PROJECT_VERSION}"
COMMENT "${PACKER_PACKAGE_FILE_NAME_EXT} created"
)
My goal is to copy directory (and its contents) to my directory ${PROJECT_BINARY_DIR}/${PROJECT_NAME}-${PROJECT_VERSION}. The only file in the directory is CMakeLists.txt, the rest are just bunch of empty "src", "data" and "po" files, any ideas

You do it wrong. There is a better way to produce a distribution tarball.
Use install command and CPack module.
Here you may find a brief tutorial on CPack with example project.

If you want to copy a directory you should use cmake -E copy_directory.
But if you want to create a source package, please have a look into cpack, it can also create source packages.

Related

Force custom command to always run without first deleting the output

I have a setup where I use a custom command to check the current hash of a git repository so that other commands can clone it if it has updated
add_custom_command(
OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/module_VERSION.txt
COMMAND ${GIT_EXECUTABLE} ls-remote ${MODULE_URL} master > ${CMAKE_CURRENT_BINARY_DIR}/module_VERSION.txt.tmp
COMMAND ${CMAKE_COMMAND} -E copy_if_different ${CMAKE_CURRENT_BINARY_DIR}/module_VERSION.txt.tmp ${CMAKE_CURRENT_BINARY_DIR}/module_VERSION.txt
COMMAND ${CMAKE_COMMAND} -E rm ${CMAKE_CURRENT_BINARY_DIR}/module_VERSION.txt.tmp
)
Of course this will only run once as CMake sees no reason to rerun it. I can force it to run by adding a second (dummy) output - CMake then recognises that this output doesn't exist and then reruns the rule. However the Makefile that this generates actually deletes module_VERSION.txt before running the command rendering the whole pursuit pointless (Ninja does not have this problem).
I am able to get this to work but in an extremely hacky way: creating another target that always runs and then generating a dependency on this.
# Use echo_append as a no-op
add_custom_command(
OUTPUT module_FORCERUN
COMMAND ${CMAKE_COMMAND} -E echo_append
)
add_custom_command(
OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/module_VERSION.txt
COMMAND ${GIT_EXECUTABLE} ls-remote ${MODULE_URL} master > ${CMAKE_CURRENT_BINARY_DIR}/module_VERSION.txt.tmp
COMMAND ${CMAKE_COMMAND} -E copy_if_different ${CMAKE_CURRENT_BINARY_DIR}/module_VERSION.txt.tmp ${CMAKE_CURRENT_BINARY_DIR}/module_VERSION.txt
COMMAND ${CMAKE_COMMAND} -E rm ${CMAKE_CURRENT_BINARY_DIR}/module_VERSION.txt.tmp
DEPENDS module_FORCERUN
)
This seems just really hacky and like it could be relying on some corner cases in cmake which aren't guaranteed to be stable. Is there a better way to get this working?
I am using cmake 3.21.3
Use add_custom_target for implement "always run" functionality and via BYPRODUCTS keyword specify the file which it could produce/update:
add_custom_target(update_module_version
BYPRODUCTS ${CMAKE_CURRENT_BINARY_DIR}/module_VERSION.txt
COMMAND ${GIT_EXECUTABLE} ls-remote ${MODULE_URL} master > ${CMAKE_CURRENT_BINARY_DIR}/module_VERSION.txt.tmp
COMMAND ${CMAKE_COMMAND} -E copy_if_different ${CMAKE_CURRENT_BINARY_DIR}/module_VERSION.txt.tmp ${CMAKE_CURRENT_BINARY_DIR}/module_VERSION.txt
COMMAND ${CMAKE_COMMAND} -E rm ${CMAKE_CURRENT_BINARY_DIR}/module_VERSION.txt.tmp
)
That way, if any other target will depend on update_module_version one, the module_VERSION.txt file will be created/updated before evaluation of the target.
Such target-level dependency will be created automatically by CMake, if given file will be listed as dependency for target/command in the same directory, where target update_module_version is created:
add_custom_command(OUTPUT <...>
DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/module_VERSION.txt
COMMAND <...>
)
From other directories the target-level dependency should be specified explicitly:
# If used in other directories
add_custom_command(OUTPUT <...>
DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/module_VERSION.txt
update_module_version
COMMAND <...>
)

Using generator expression in `cmake -E copy` command

I am trying to copy dll files from my bin folder to a different folder. I want to copy files from bin/Debug when building in Debug and from bin/Release when building in Release. This is what I currently use (and which does not work).
file(GLOB library_files_debug ${outputdirectory_root}/Debug/*.dll)
file(GLOB library_files_release ${outputdirectory_root}/Release/*.dll)
add_custom_target(copy_dlls_to_wheel ALL
DEPENDS setup.py
COMMAND ${CMAKE_COMMAND} -E echo "Debug files: $<$<CONFIG:Debug>:${library_files_debug}>"
COMMAND ${CMAKE_COMMAND} -E echo "Release files: $<$<CONFIG:Release>:${library_files_release}>"
COMMAND ${CMAKE_COMMAND} -E echo "Destination dir: ${CMAKE_BINARY_DIR}/python/${PROJECT_NAME}"
COMMAND ${CMAKE_COMMAND} -E copy $<$<CONFIG:Debug>:${library_files_debug}> $<$<CONFIG:Release>:${library_files_release}> ${CMAKE_BINARY_DIR}/python/${PROJECT_NAME}
)
I am running on Windows 10, and use Visual Studio to build. When the above target copy_dlls_to_wheel is built in Debug, the first echo statement prints out the correct dll files, and the second echo is empty. However, no files are copied. Instead I get the error message The system cannot find the path specified.
I have also tried to replace the last line with
COMMAND ${CMAKE_COMMAND} -E copy $<$<CONFIG:Debug>:${library_files_debug}> ${CMAKE_BINARY_DIR}/python/${PROJECT_NAME}
, but I get the same result.
However, when I remove the generator expression, and use
COMMAND ${CMAKE_COMMAND} -E copy ${library_files_debug} ${CMAKE_BINARY_DIR}/python/${PROJECT_NAME}
the files are copied correctly to my output folder. I am pretty confident my generator expression is correct, since I get the expected output from the echo commands. Are generator expressions not supported when using cmake -E copy, or is there something else I am doing wrong?
CMake's command line copy is able to process multiple files when you simply provide a list, which is why this works:
COMMAND ${CMAKE_COMMAND} -E copy ${library_files_debug} ${CMAKE_BINARY_DIR}/python/${PROJECT_NAME}
This is expanded to a space-separated list of files when the copy command is ultimately executed, which is the expected syntax.
cmake.exe -E copy mylib1.dll mylib2.dll /your/binary/dir/python/proj
However, when wrapped in a generator expression, the list will not be interpreted correctly by CMake. While the generator expression will be evaluated correctly, the list will be kept as a semicolon-separated list of files, which is the incorrect syntax:
cmake.exe -E copy "mylib1.dll;mylib2.dll" /your/binary/dir/python/proj
This causes the copy command to fail.
To work-around this issue, you could loop over each DLL file you want to copy, if there aren't too many. Something like this could work:
# Loop through the Debug files.
foreach(cur_file ${library_files_debug})
get_filename_component(file_name ${cur_file} NAME)
add_custom_target(copy_dlls_to_wheel_debug_${file_name} ALL
DEPENDS setup.py
COMMAND ${CMAKE_COMMAND} -E echo "DLL file: ${cur_file}"
COMMAND ${CMAKE_COMMAND} -E echo "Destination dir: ${CMAKE_BINARY_DIR}/python/${PROJECT_NAME}"
COMMAND ${CMAKE_COMMAND} -E copy $<$<CONFIG:Debug>:${cur_file}> ${CMAKE_BINARY_DIR}/python/${PROJECT_NAME}
)
endforeach()
# Loop through the Release files.
foreach(cur_file ${library_files_release})
get_filename_component(file_name ${cur_file} NAME)
add_custom_target(copy_dlls_to_wheel_release_${file_name} ALL
DEPENDS setup.py
COMMAND ${CMAKE_COMMAND} -E echo "DLL file: ${cur_file}"
COMMAND ${CMAKE_COMMAND} -E echo "Destination dir: ${CMAKE_BINARY_DIR}/python/${PROJECT_NAME}"
COMMAND ${CMAKE_COMMAND} -E copy $<$<CONFIG:Release>:${cur_file}> ${CMAKE_BINARY_DIR}/python/${PROJECT_NAME}
)
endforeach()
A quicker solution might be to bundle up your DLLs, using CMake's tar command line utility, copy them, then extract them, as suggested in this answer. CMake's tar command does not seem to accept lists wrapped in generator expressions either, so the list of files to bundle together is written to a file.
file(GLOB library_files_debug ${outputdirectory_root}/Debug/*.dll)
file(GLOB library_files_release ${outputdirectory_root}/Release/*.dll)
# Write the filenames (not full path) of the files to pack to file
set(debug_content "")
set(release_content "")
foreach(lib_file ${library_files_debug})
get_filename_component(file_name ${lib_file} NAME)
set(debug_content "${debug_content}${file_name}\n")
endforeach(lib_file ${library_files_debug})
foreach(lib_file ${library_files_release})
get_filename_component(file_name ${lib_file} NAME)
set(release_content "${release_content}${file_name}\n")
endforeach(lib_file ${library_files_release})
set(filenames_debug ${outputdirectory_root}/debug_files.txt)
set(filenames_release ${outputdirectory_root}/release_files.txt)
file(WRITE ${filenames_debug} ${debug_content})
file(WRITE ${filenames_release} ${release_content})
# Read either the list of debug or release files, and pack files
add_custom_command(
TARGET bdist PRE_BUILD
COMMAND ${CMAKE_COMMAND} -E tar "cfj" ${outputdirectory_root}/temp.tar --files-from="$<IF:$<CONFIG:Debug>,${filenames_debug},${filenames_release}>"
WORKING_DIRECTORY ${outputdirectory_root}/$<CONFIG>)
# Unpack the files in the folder building the python wheel
add_custom_command(
TARGET bdist PRE_BUILD
COMMAND ${CMAKE_COMMAND} -E rename ${outputdirectory_root}/temp.tar temp.tar
COMMAND ${CMAKE_COMMAND} -E tar "xfj" temp.tar
COMMAND ${CMAKE_COMMAND} -E remove temp.tar
WORKING_DIRECTORY ${CMAKE_BINARY_DIR}/python/${PROJECT_NAME})

CMake command copy for symlink

I have following command:
add_custom_command(
TARGET Packaging POST_BUILD
COMMAND ${CMAKE_COMMAND} -E copy
source_file
target_file )
Sometimes the source_file is a symlink. However, when it is copied, the referenced file is copied not the symlink.
How can I tell CMake command to copy the symlink as it is without de-referencing it?
It seems that there is no direct solution in CMake till now https://gitlab.kitware.com/cmake/cmake/issues/14609
A work around is to call a shell script that does the trick.
instead built-in "copy" you can use linux "cp" command with corresponded switches:
add_custom_command(
TARGET Packaging POST_BUILD
COMMAND cp -a -u
source_file
target_file )

CMake unzip automatically(while building) when the zip file changes

I am currently using execute_command to unzip some files before building.
I would like to unzip the folder that is in effect replace the old files with new file in the destination folder when the zip file in the source changes. Can anyone give me some suggestions?
Currently I am doing something like this,
execute_process(
COMMAND ${CMAKE_COMMAND} -E tar xzf ${CMAKE_SOURCE_DIR}/abc.zip
WORKING_DIRECTORY ${CMAKE_BINARY_DIR}
)
I tried with add_custom_command() but I am executing it for every build.
I only want it to unzip if the source zip file changes.
add_custom_command( OUTPUT ${LibsList}
COMMAND ${CMAKE_COMMAND} -E tar xzf ${CMAKE_SOURCE_DIR}/libs.zip
WORKING_DIRECTORY ${CMAKE_BINARY_DIR}
DEPENDS ${CMAKE_SOURCE_DIR}/libs.zip )
They mostly contain header files and a few shared libraries. I usually need the header files at build time and shared libraries at run time. If possible I would not give the list of files in OUTPUT as it is very large
I achieve this, at least for my scenario using the code below,
add_custom_target( unZip ALL)
add_custom_command(TARGET unZip PRE_BUILD
COMMAND ${CMAKE_COMMAND} -E remove_directory ${CMAKE_BINARY_DIR}/abc/
COMMAND ${CMAKE_COMMAND} -E tar xzf {CMAKE_SOURCE_DIR}/abc.zip
WORKING_DIRECTORY ${CMAKE_BINARY_DIR}
DEPENDS ${CMAKE_SOURCE_DIR}/abc.zip
COMMENT "Unpacking abc.zip"
VERBATIM)
Now I made all target dependent on "unZip". This way when rebuilding unZip occurs or at build time if abc.zip changes, unZip occurs.

Creating a directory in CMake

In CMake, I want to create a directory if it doesn't already exist. How can I do this?
When do you want to create the directory?
At build system generation
To create a directory when CMake generates the build system,
file(MAKE_DIRECTORY ${directory})
At build time
In the add_custom_command() command (which adds a custom build rule to the generated build system), and the add_custom_target() command (which adds a target with no output so it will always be built), you specify the commands to execute at build time. Create a directory by executing the command ${CMAKE_COMMAND} -E make_directory. For example:
add_custom_target(build-time-make-directory ALL
COMMAND ${CMAKE_COMMAND} -E make_directory ${directory})
At install time
To create a directory at install time,
install(DIRECTORY DESTINATION ${directory})
To create a directory at install time,
install(DIRECTORY DESTINATION ${directory})
These will both run at configure time:
file(MAKE_DIRECTORY ${directory})
execute_process(COMMAND ${CMAKE_COMMAND} -E make_directory ${directory})
To create during the build, use a custom target:
add_custom_target(mytargetname ALL COMMAND ${CMAKE_COMMAND} -E make_directory ${directory})
In addition to Chin Huang's reply, you can also do this at build time with add_custom_command:
add_custom_command(TARGET ${target_name} PRE_BUILD COMMAND ${CMAKE_COMMAND} -E make_directory ${directory})
You can also change the moment, when your directory is created with PRE_BUILD | PRE_LINK | POST_BUILD parameters.