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Diffstat (limited to 'cmake/Util.cmake')
| -rw-r--r-- | cmake/Util.cmake | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/cmake/Util.cmake b/cmake/Util.cmake new file mode 100644 index 0000000000..b485f4606b --- /dev/null +++ b/cmake/Util.cmake @@ -0,0 +1,145 @@ +# Defines a target that depends on FILES and the files found by globbing +# when using GLOB_PAT and GLOB_DIRS. The target will rerun if any files it +# depends on has changed. Which files the target will run the command on +# depends on the value of TOUCH_STRATEGY. +# +# Options: +# REQUIRED - Abort if COMMAND doesn't exist. +# +# Single value arguments: +# TARGET - Name of the target +# COMMAND - Path of the command to be run +# GLOB_PAT - Glob pattern to use. Only used if GLOB_DIRS is specified +# TOUCH_STRATEGY - Specify touch strategy, meaning decide how to group files +# and connect them to a specific touch file. +# +# For example, let us say we have file A and B and that we create a touch file +# for each of them, TA and TB. This would essentially make file A and B +# independent of each other, meaning that if I change file A and run the +# target, then the target will only run its commands for file A and ignore +# file B. +# +# Another example: let's say we have file A and B, but now we create only a +# single touch file T for both of them. This would mean that if I change +# either file A or B, then the target will run its commands on both A and B. +# Meaning that even if I only change file A, the target will still run +# commands on both A and B. +# +# The more touch files we create for a target, the fewer commands we'll need +# to rerun, and by extension, the more time we'll save. Unfortunately, the +# more touch files we create the more intermediary targets will be created, +# one for each touch file. This makes listing all targets with +# `cmake --build build --target help` less useful since each touch file will +# be listed. The tradeoff that needs to be done here is between performance +# and "discoverability". As a general guideline: the more popular a target is +# and the more time it takes to run it, the more granular you want your touch +# files to be. Conversely, if a target rarely needs to be run or if it's fast, +# then you should create fewer targets. +# +# Possible values for TOUCH_STRATEGY: +# "SINGLE": create a single touch file for all files. +# "PER_FILE": create a touch file for each file. Defaults to this if +# TOUCH_STRATEGY isn't specified. +# "PER_DIR": create a touch file for each directory. +# +# List arguments: +# FLAGS - List of flags to use after COMMAND +# FILES - List of files to use COMMAND on. It's possible to combine this +# with GLOB_PAT and GLOB_DIRS; the files found by globbing will +# simple be added to FILES +# GLOB_DIRS - The directories to recursively search for files with extension +# GLOB_PAT +# +function(add_glob_targets) + cmake_parse_arguments(ARG + "REQUIRED" + "TARGET;COMMAND;GLOB_PAT;TOUCH_STRATEGY" + "FLAGS;FILES;GLOB_DIRS" + ${ARGN} + ) + + if(NOT ARG_COMMAND) + add_custom_target(${ARG_TARGET}) + if(ARG_REQUIRED) + add_custom_command(TARGET ${ARG_TARGET} + COMMAND ${CMAKE_COMMAND} -E echo "${ARG_TARGET}: ${ARG_COMMAND} not found" + COMMAND false) + else() + add_custom_command(TARGET ${ARG_TARGET} + COMMAND ${CMAKE_COMMAND} -E echo "${ARG_TARGET} SKIP: ${ARG_COMMAND} not found") + endif() + return() + endif() + + foreach(gd ${ARG_GLOB_DIRS}) + file(GLOB_RECURSE globfiles ${PROJECT_SOURCE_DIR}/${gd}/${ARG_GLOB_PAT}) + list(APPEND ARG_FILES ${globfiles}) + endforeach() + + if(NOT ARG_TOUCH_STRATEGY) + set(ARG_TOUCH_STRATEGY PER_FILE) + endif() + set(POSSIBLE_TOUCH_STRATEGIES SINGLE PER_FILE PER_DIR) + if(NOT ARG_TOUCH_STRATEGY IN_LIST POSSIBLE_TOUCH_STRATEGIES) + message(FATAL_ERROR "Unrecognized value for TOUCH_STRATEGY: ${ARG_TOUCH_STRATEGY}") + endif() + + if(ARG_TOUCH_STRATEGY STREQUAL SINGLE) + set(touch_file ${TOUCHES_DIR}/ran-${ARG_TARGET}) + add_custom_command( + OUTPUT ${touch_file} + COMMAND ${CMAKE_COMMAND} -E touch ${touch_file} + COMMAND ${ARG_COMMAND} ${ARG_FLAGS} ${ARG_FILES} + WORKING_DIRECTORY ${PROJECT_SOURCE_DIR} + DEPENDS ${ARG_FILES}) + list(APPEND touch_list ${touch_file}) + elseif(ARG_TOUCH_STRATEGY STREQUAL PER_FILE) + set(touch_dir ${TOUCHES_DIR}/${ARG_TARGET}) + file(MAKE_DIRECTORY ${touch_dir}) + foreach(f ${ARG_FILES}) + string(REGEX REPLACE "^${PROJECT_SOURCE_DIR}/" "" tf ${f}) + string(REGEX REPLACE "[/.]" "-" tf ${tf}) + set(touch_file ${touch_dir}/ran-${tf}) + add_custom_command( + OUTPUT ${touch_file} + COMMAND ${CMAKE_COMMAND} -E touch ${touch_file} + COMMAND ${ARG_COMMAND} ${ARG_FLAGS} ${f} + WORKING_DIRECTORY ${PROJECT_SOURCE_DIR} + DEPENDS ${f}) + list(APPEND touch_list ${touch_file}) + endforeach() + elseif(ARG_TOUCH_STRATEGY STREQUAL PER_DIR) + set(touch_dirs) + foreach(f ${ARG_FILES}) + get_filename_component(out ${f} DIRECTORY) + list(APPEND touch_dirs ${out}) + endforeach() + list(REMOVE_DUPLICATES touch_dirs) + + foreach(touch_dir ${touch_dirs}) + set(relevant_files) + foreach(f ${ARG_FILES}) + get_filename_component(out ${f} DIRECTORY) + if(${touch_dir} STREQUAL ${out}) + list(APPEND relevant_files ${f}) + endif() + endforeach() + + set(td ${TOUCHES_DIR}/${ARG_TARGET}) + file(MAKE_DIRECTORY ${td}) + string(REGEX REPLACE "^${PROJECT_SOURCE_DIR}/" "" tf ${touch_dir}) + string(REGEX REPLACE "[/.]" "-" tf ${tf}) + set(touch_file ${td}/ran-${tf}) + + add_custom_command( + OUTPUT ${touch_file} + COMMAND ${CMAKE_COMMAND} -E touch ${touch_file} + COMMAND ${ARG_COMMAND} ${ARG_FLAGS} ${relevant_files} + WORKING_DIRECTORY ${PROJECT_SOURCE_DIR} + DEPENDS ${relevant_files}) + list(APPEND touch_list ${touch_file}) + endforeach() + endif() + + add_custom_target(${ARG_TARGET} DEPENDS ${touch_list}) +endfunction() |