qt5base-lts/cmake/QtCMakeHelpers.cmake

# qt_configure_file(OUTPUT output-file <INPUT input-file | CONTENT content>)
# input-file is relative to ${CMAKE_CURRENT_SOURCE_DIR}
# output-file is relative to ${CMAKE_CURRENT_BINARY_DIR}
#
# This function is similar to file(GENERATE OUTPUT) except it writes the content
# to the file at configure time, rather than at generate time. Once CMake 3.18 is released, it can use file(CONFIGURE) in its implmenetation. Until then, it
# uses configure_file() with a generic input file as source, when used with the CONTENT signature.
function(qt_configure_file)
    qt_parse_all_arguments(arg "qt_configure_file" "" "OUTPUT;INPUT;CONTENT" "" ${ARGN})

    if(NOT arg_OUTPUT)
        message(FATAL_ERROR "No output file provided to qt_configure_file.")
    endif()

    if(arg_CONTENT)
        set(template_name "QtFileConfigure.txt.in")
        # When building qtbase, use the source template file.
        # Otherwise use the installed file (basically wherever Qt6 package is found).
        # This should work for non-prefix and superbuilds as well.
        if(QtBase_SOURCE_DIR)
            set(input_file "${QtBase_SOURCE_DIR}/cmake/${template_name}")
        else()
            set(input_file "${_qt_6_config_cmake_dir}/${template_name}")
        endif()
        set(__qt_file_configure_content "${arg_CONTENT}")
    elseif(arg_INPUT)
        set(input_file "${arg_INPUT}")
    else()
        message(FATAL_ERROR "No input value provided to qt_configure_file.")
    endif()

    configure_file("${input_file}" "${arg_OUTPUT}" @ONLY)
endfunction()

# A version of cmake_parse_arguments that makes sure all arguments are processed and errors out
# with a message about ${type} having received unknown arguments.
macro(qt_parse_all_arguments result type flags options multiopts)
    cmake_parse_arguments(${result} "${flags}" "${options}" "${multiopts}" ${ARGN})
    if(DEFINED ${result}_UNPARSED_ARGUMENTS)
        message(FATAL_ERROR "Unknown arguments were passed to ${type} (${${result}_UNPARSED_ARGUMENTS}).")
    endif()
endmacro()

# Print all variables defined in the current scope.
macro(qt_debug_print_variables)
    cmake_parse_arguments(__arg "DEDUP" "" "MATCH;IGNORE" ${ARGN})
    message("Known Variables:")
    get_cmake_property(__variableNames VARIABLES)
    list (SORT __variableNames)
    if (__arg_DEDUP)
        list(REMOVE_DUPLICATES __variableNames)
    endif()

    foreach(__var ${__variableNames})
        set(__ignore OFF)
        foreach(__i ${__arg_IGNORE})
            if(__var MATCHES "${__i}")
                set(__ignore ON)
                break()
            endif()
        endforeach()

        if (__ignore)
            continue()
        endif()

        set(__show OFF)
        foreach(__i ${__arg_MATCH})
            if(__var MATCHES "${__i}")
                set(__show ON)
                break()
            endif()
        endforeach()

        if (__show)
            message("    ${__var}=${${__var}}.")
        endif()
    endforeach()
endmacro()

macro(assert)
    if (${ARGN})
    else()
        message(FATAL_ERROR "ASSERT: ${ARGN}.")
    endif()
endmacro()

# Takes a list of path components and joins them into one path separated by forward slashes "/",
# and saves the path in out_var.
function(qt_path_join out_var)
    string(JOIN "/" path ${ARGN})
    set(${out_var} ${path} PARENT_SCOPE)
endfunction()

# qt_remove_args can remove arguments from an existing list of function
# arguments in order to pass a filtered list of arguments to a different function.
# Parameters:
#   out_var: result of remove all arguments specified by ARGS_TO_REMOVE from ALL_ARGS
#   ARGS_TO_REMOVE: Arguments to remove.
#   ALL_ARGS: All arguments supplied to cmake_parse_arguments or
#   qt_parse_all_arguments
#   from which ARGS_TO_REMOVE should be removed from. We require all the
#   arguments or we can't properly identify the range of the arguments detailed
#   in ARGS_TO_REMOVE.
#   ARGS: Arguments passed into the function, usually ${ARGV}
#
#   E.g.:
#   We want to forward all arguments from foo to bar, execpt ZZZ since it will
#   trigger an error in bar.
#
#   foo(target BAR .... ZZZ .... WWW ...)
#   bar(target BAR.... WWW...)
#
#   function(foo target)
#       qt_parse_all_arguments(arg "" "" "BAR;ZZZ;WWW ${ARGV})
#       qt_remove_args(forward_args
#           ARGS_TO_REMOVE ${target} ZZZ
#           ALL_ARGS ${target} BAR ZZZ WWW
#           ARGS ${ARGV}
#       )
#       bar(${target} ${forward_args})
#   endfunction()
#
function(qt_remove_args out_var)
    cmake_parse_arguments(arg "" "" "ARGS_TO_REMOVE;ALL_ARGS;ARGS" ${ARGN})
    set(result ${arg_ARGS})
    foreach(arg IN LISTS arg_ARGS_TO_REMOVE)
        # find arg
        list(FIND result ${arg} find_result)
        if (NOT find_result EQUAL -1)
            # remove arg
            list(REMOVE_AT result ${find_result})
            list(LENGTH result result_len)
            if(find_result EQUAL result_len)
                # We removed the last argument, could have been an option keyword
                continue()
            endif()
            list(GET result ${find_result} arg_current)
            # remove values until we hit another arg or the end of the list
            while(NOT "${arg_current}" IN_LIST arg_ALL_ARGS AND find_result LESS result_len)
                list(REMOVE_AT result ${find_result})
                list(LENGTH result result_len)
                if (NOT find_result EQUAL result_len)
                    list(GET result ${find_result} arg_current)
                endif()
            endwhile()
        endif()
    endforeach()
    set(${out_var} "${result}" PARENT_SCOPE)
endfunction()

# Creates a regular expression that exactly matches the given string
# Found in https://gitlab.kitware.com/cmake/cmake/issues/18580
function(qt_re_escape out_var str)
    string(REGEX REPLACE "([][+.*()^])" "\\\\\\1" regex "${str}")
    set(${out_var} ${regex} PARENT_SCOPE)
endfunction()

# Input: string
# Output: regex string to match the string case insensitively
# Example: "Release" -> "^([Rr][Ee][Ll][Ee][Aa][Ss][Ee])$"
#
# Regular expressions like this are used in cmake_install.cmake files for case-insensitive string
# comparison.
function(qt_create_case_insensitive_regex out_var input)
    set(result "^(")
    string(LENGTH "${input}" n)
    math(EXPR n "${n} - 1")
    foreach(i RANGE 0 ${n})
        string(SUBSTRING "${input}" ${i} 1 c)
        string(TOUPPER "${c}" uc)
        string(TOLOWER "${c}" lc)
        string(APPEND result "[${uc}${lc}]")
    endforeach()
    string(APPEND result ")$")
    set(${out_var} "${result}" PARENT_SCOPE)
endfunction()

# Gets a target property, and returns "" if the property was not found
function(qt_internal_get_target_property out_var target property)
    get_target_property(result "${target}" "${property}")
    if("${result}" STREQUAL "result-NOTFOUND")
        set(result "")
    endif()
    set(${out_var} "${result}" PARENT_SCOPE)
endfunction()