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Diffstat (limited to 'Modules/FindFLEX.cmake')
| -rw-r--r-- | Modules/FindFLEX.cmake | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/Modules/FindFLEX.cmake b/Modules/FindFLEX.cmake new file mode 100644 index 0000000..d22b7ec --- /dev/null +++ b/Modules/FindFLEX.cmake @@ -0,0 +1,221 @@ +# Distributed under the OSI-approved BSD 3-Clause License. See accompanying +# file Copyright.txt or https://cmake.org/licensing for details. + +#[=======================================================================[.rst: +FindFLEX +-------- + +Find Fast Lexical Analyzer (Flex) executable and provides a macro +to generate custom build rules + + + +The module defines the following variables: + +:: + + FLEX_FOUND - True is flex executable is found + FLEX_EXECUTABLE - the path to the flex executable + FLEX_VERSION - the version of flex + FLEX_LIBRARIES - The flex libraries + FLEX_INCLUDE_DIRS - The path to the flex headers + + + +The minimum required version of flex can be specified using the +standard syntax, e.g. :command:`find_package(FLEX 2.5.13)` + + + +If flex is found on the system, the module provides the macro: + +:: + + FLEX_TARGET(Name FlexInput FlexOutput + [COMPILE_FLAGS <string>] + [DEFINES_FILE <string>] + ) + +which creates a custom command to generate the ``FlexOutput`` file from +the ``FlexInput`` file. If ``COMPILE_FLAGS`` option is specified, the next +parameter is added to the flex command line. If flex is configured to +output a header file, the ``DEFINES_FILE`` option may be used to specify its +name. Name is an alias used to get details of this custom command. +Indeed the macro defines the following variables: + +:: + + FLEX_${Name}_DEFINED - true is the macro ran successfully + FLEX_${Name}_OUTPUTS - the source file generated by the custom rule, an + alias for FlexOutput + FLEX_${Name}_INPUT - the flex source file, an alias for ${FlexInput} + FLEX_${Name}_OUTPUT_HEADER - the header flex output, if any. + + + +Flex scanners often use tokens defined by Bison: the code generated +by Flex depends of the header generated by Bison. This module also +defines a macro: + +:: + + ADD_FLEX_BISON_DEPENDENCY(FlexTarget BisonTarget) + +which adds the required dependency between a scanner and a parser +where ``FlexTarget`` and ``BisonTarget`` are the first parameters of +respectively ``FLEX_TARGET`` and ``BISON_TARGET`` macros. + +:: + + ==================================================================== + Example: + + + +:: + + find_package(BISON) + find_package(FLEX) + + + +:: + + BISON_TARGET(MyParser parser.y ${CMAKE_CURRENT_BINARY_DIR}/parser.cpp) + FLEX_TARGET(MyScanner lexer.l ${CMAKE_CURRENT_BINARY_DIR}/lexer.cpp) + ADD_FLEX_BISON_DEPENDENCY(MyScanner MyParser) + + + +:: + + include_directories(${CMAKE_CURRENT_BINARY_DIR}) + add_executable(Foo + Foo.cc + ${BISON_MyParser_OUTPUTS} + ${FLEX_MyScanner_OUTPUTS} + ) + target_link_libraries(Foo ${FLEX_LIBRARIES}) + ==================================================================== +#]=======================================================================] + +find_program(FLEX_EXECUTABLE NAMES flex win_flex DOC "path to the flex executable") +mark_as_advanced(FLEX_EXECUTABLE) + +find_library(FL_LIBRARY NAMES fl + DOC "Path to the fl library") + +find_path(FLEX_INCLUDE_DIR FlexLexer.h + DOC "Path to the flex headers") + +mark_as_advanced(FL_LIBRARY FLEX_INCLUDE_DIR) + +set(FLEX_INCLUDE_DIRS ${FLEX_INCLUDE_DIR}) +set(FLEX_LIBRARIES ${FL_LIBRARY}) + +if(FLEX_EXECUTABLE) + + execute_process(COMMAND ${FLEX_EXECUTABLE} --version + OUTPUT_VARIABLE FLEX_version_output + ERROR_VARIABLE FLEX_version_error + RESULT_VARIABLE FLEX_version_result + OUTPUT_STRIP_TRAILING_WHITESPACE) + if(NOT ${FLEX_version_result} EQUAL 0) + if(FLEX_FIND_REQUIRED) + message(SEND_ERROR "Command \"${FLEX_EXECUTABLE} --version\" failed with output:\n${FLEX_version_output}\n${FLEX_version_error}") + else() + message("Command \"${FLEX_EXECUTABLE} --version\" failed with output:\n${FLEX_version_output}\n${FLEX_version_error}\nFLEX_VERSION will not be available") + endif() + else() + # older versions of flex printed "/full/path/to/executable version X.Y" + # newer versions use "basename(executable) X.Y" + get_filename_component(FLEX_EXE_NAME_WE "${FLEX_EXECUTABLE}" NAME_WE) + get_filename_component(FLEX_EXE_EXT "${FLEX_EXECUTABLE}" EXT) + string(REGEX REPLACE "^.*${FLEX_EXE_NAME_WE}(${FLEX_EXE_EXT})?\"? (version )?([0-9]+[^ ]*)( .*)?$" "\\3" + FLEX_VERSION "${FLEX_version_output}") + unset(FLEX_EXE_EXT) + unset(FLEX_EXE_NAME_WE) + endif() + + #============================================================ + # FLEX_TARGET (public macro) + #============================================================ + # + macro(FLEX_TARGET Name Input Output) + set(FLEX_TARGET_outputs "${Output}") + set(FLEX_EXECUTABLE_opts "") + + set(FLEX_TARGET_PARAM_OPTIONS) + set(FLEX_TARGET_PARAM_ONE_VALUE_KEYWORDS + COMPILE_FLAGS + DEFINES_FILE + ) + set(FLEX_TARGET_PARAM_MULTI_VALUE_KEYWORDS) + + cmake_parse_arguments( + FLEX_TARGET_ARG + "${FLEX_TARGET_PARAM_OPTIONS}" + "${FLEX_TARGET_PARAM_ONE_VALUE_KEYWORDS}" + "${FLEX_TARGET_MULTI_VALUE_KEYWORDS}" + ${ARGN} + ) + + set(FLEX_TARGET_usage "FLEX_TARGET(<Name> <Input> <Output> [COMPILE_FLAGS <string>] [DEFINES_FILE <string>]") + + if(NOT "${FLEX_TARGET_ARG_UNPARSED_ARGUMENTS}" STREQUAL "") + message(SEND_ERROR ${FLEX_TARGET_usage}) + else() + if(NOT "${FLEX_TARGET_ARG_COMPILE_FLAGS}" STREQUAL "") + set(FLEX_EXECUTABLE_opts "${FLEX_TARGET_ARG_COMPILE_FLAGS}") + separate_arguments(FLEX_EXECUTABLE_opts) + endif() + if(NOT "${FLEX_TARGET_ARG_DEFINES_FILE}" STREQUAL "") + list(APPEND FLEX_TARGET_outputs "${FLEX_TARGET_ARG_DEFINES_FILE}") + list(APPEND FLEX_EXECUTABLE_opts --header-file=${FLEX_TARGET_ARG_DEFINES_FILE}) + endif() + + add_custom_command(OUTPUT ${FLEX_TARGET_outputs} + COMMAND ${FLEX_EXECUTABLE} ${FLEX_EXECUTABLE_opts} -o${Output} ${Input} + VERBATIM + DEPENDS ${Input} + COMMENT "[FLEX][${Name}] Building scanner with flex ${FLEX_VERSION}" + WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}) + + set(FLEX_${Name}_DEFINED TRUE) + set(FLEX_${Name}_OUTPUTS ${Output}) + set(FLEX_${Name}_INPUT ${Input}) + set(FLEX_${Name}_COMPILE_FLAGS ${FLEX_EXECUTABLE_opts}) + if("${FLEX_TARGET_ARG_DEFINES_FILE}" STREQUAL "") + set(FLEX_${Name}_OUTPUT_HEADER "") + else() + set(FLEX_${Name}_OUTPUT_HEADER ${FLEX_TARGET_ARG_DEFINES_FILE}) + endif() + endif() + endmacro() + #============================================================ + + + #============================================================ + # ADD_FLEX_BISON_DEPENDENCY (public macro) + #============================================================ + # + macro(ADD_FLEX_BISON_DEPENDENCY FlexTarget BisonTarget) + + if(NOT FLEX_${FlexTarget}_OUTPUTS) + message(SEND_ERROR "Flex target `${FlexTarget}' does not exist.") + endif() + + if(NOT BISON_${BisonTarget}_OUTPUT_HEADER) + message(SEND_ERROR "Bison target `${BisonTarget}' does not exist.") + endif() + + set_source_files_properties(${FLEX_${FlexTarget}_OUTPUTS} + PROPERTIES OBJECT_DEPENDS ${BISON_${BisonTarget}_OUTPUT_HEADER}) + endmacro() + #============================================================ + +endif() + +include(${CMAKE_CURRENT_LIST_DIR}/FindPackageHandleStandardArgs.cmake) +FIND_PACKAGE_HANDLE_STANDARD_ARGS(FLEX REQUIRED_VARS FLEX_EXECUTABLE + VERSION_VAR FLEX_VERSION) |