1 # - Find flex executable and provides a macro to generate custom build rules
3 # The module defines the following variables:
4 # FLEX_FOUND - true is flex executable is found
5 # FLEX_EXECUTABLE - the path to the flex executable
6 # FLEX_VERSION - the version of flex
7 # FLEX_LIBRARIES - The flex libraries
9 # If flex is found on the system, the module provides the macro:
10 # FLEX_TARGET(Name FlexInput FlexOutput [COMPILE_FLAGS <string>])
11 # which creates a custom command to generate the <FlexOutput> file from
12 # the <FlexInput> file. If COMPILE_FLAGS option is specified, the next
13 # parameter is added to the flex command line. Name is an alias used to
14 # get details of this custom command. Indeed the macro defines the
15 # following variables:
16 # FLEX_${Name}_DEFINED - true is the macro ran successfully
17 # FLEX_${Name}_OUTPUTS - the source file generated by the custom rule, an
18 # alias for FlexOutput
19 # FLEX_${Name}_INPUT - the flex source file, an alias for ${FlexInput}
21 # Flex scanners oftenly use tokens defined by Bison: the code generated
22 # by Flex depends of the header generated by Bison. This module also
24 # ADD_FLEX_BISON_DEPENDENCY(FlexTarget BisonTarget)
25 # which adds the required dependency between a scanner and a parser
26 # where <FlexTarget> and <BisonTarget> are the first parameters of
27 # respectively FLEX_TARGET and BISON_TARGET macros.
29 # ====================================================================
35 # BISON_TARGET(MyParser parser.y ${CMAKE_CURRENT_BINARY_DIR}/parser.cpp
36 # FLEX_TARGET(MyScanner lexer.l ${CMAKE_CURRENT_BIANRY_DIR}/lexer.cpp)
37 # ADD_FLEX_BISON_DEPENDENCY(MyScanner MyParser)
39 # include_directories(${CMAKE_CURRENT_BINARY_DIR})
42 # ${BISON_MyParser_OUTPUTS}
43 # ${FLEX_MyScanner_OUTPUTS}
45 # ====================================================================
47 #=============================================================================
48 # Copyright 2009 Kitware, Inc.
49 # Copyright 2006 Tristan Carel
51 # Distributed under the OSI-approved BSD License (the "License");
52 # see accompanying file Copyright.txt for details.
54 # This software is distributed WITHOUT ANY WARRANTY; without even the
55 # implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
56 # See the License for more information.
57 #=============================================================================
58 # (To distributed this file outside of CMake, substitute the full
59 # License text for the above reference.)
61 FIND_PROGRAM(FLEX_EXECUTABLE flex DOC "path to the flex executable")
62 MARK_AS_ADVANCED(FLEX_EXECUTABLE)
64 FIND_LIBRARY(FL_LIBRARY NAMES fl
65 DOC "path to the fl library")
66 MARK_AS_ADVANCED(FL_LIBRARY)
67 SET(FLEX_LIBRARIES ${FL_LIBRARY})
71 EXECUTE_PROCESS(COMMAND ${FLEX_EXECUTABLE} --version
72 OUTPUT_VARIABLE FLEX_version_output
73 ERROR_VARIABLE FLEX_version_error
74 RESULT_VARIABLE FLEX_version_result
75 OUTPUT_STRIP_TRAILING_WHITESPACE)
76 IF(NOT ${FLEX_version_result} EQUAL 0)
77 MESSAGE(SEND_ERROR "Command \"${FLEX_EXECUTABLE} --version\" failed with output:\n${FLEX_version_error}")
79 STRING(REGEX REPLACE "^flex (.*)$" "\\1"
80 FLEX_VERSION "${FLEX_version_output}")
83 #============================================================
84 # FLEX_TARGET (public macro)
85 #============================================================
87 MACRO(FLEX_TARGET Name Input Output)
88 SET(FLEX_TARGET_usage "FLEX_TARGET(<Name> <Input> <Output> [COMPILE_FLAGS <string>]")
91 IF("${ARGV3}" STREQUAL "COMPILE_FLAGS")
92 SET(FLEX_EXECUTABLE_opts "${ARGV4}")
93 SEPARATE_ARGUMENTS(FLEX_EXECUTABLE_opts)
95 MESSAGE(SEND_ERROR ${FLEX_TARGET_usage})
98 MESSAGE(SEND_ERROR ${FLEX_TARGET_usage})
102 ADD_CUSTOM_COMMAND(OUTPUT ${Output}
103 COMMAND ${FLEX_EXECUTABLE}
104 ARGS ${FLEX_EXECUTABLE_opts} -o${Output} ${Input}
106 COMMENT "[FLEX][${Name}] Building scanner with flex ${FLEX_VERSION}"
107 WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR})
109 SET(FLEX_${Name}_DEFINED TRUE)
110 SET(FLEX_${Name}_OUTPUTS ${Output})
111 SET(FLEX_${Name}_INPUT ${Input})
112 SET(FLEX_${Name}_COMPILE_FLAGS ${FLEX_EXECUTABLE_opts})
113 ENDMACRO(FLEX_TARGET)
114 #============================================================
117 #============================================================
118 # ADD_FLEX_BISON_DEPENDENCY (public macro)
119 #============================================================
121 MACRO(ADD_FLEX_BISON_DEPENDENCY FlexTarget BisonTarget)
123 IF(NOT FLEX_${FlexTarget}_OUTPUTS)
124 MESSAGE(SEND_ERROR "Flex target `${FlexTarget}' does not exists.")
127 IF(NOT BISON_${BisonTarget}_OUTPUT_HEADER)
128 MESSAGE(SEND_ERROR "Bison target `${BisonTarget}' does not exists.")
131 SET_SOURCE_FILES_PROPERTIES(${FLEX_${FlexTarget}_OUTPUTS}
132 PROPERTIES OBJECT_DEPENDS ${BISON_${BisonTarget}_OUTPUT_HEADER})
133 ENDMACRO(ADD_FLEX_BISON_DEPENDENCY)
134 #============================================================
136 ENDIF(FLEX_EXECUTABLE)
138 INCLUDE(FindPackageHandleStandardArgs)
139 FIND_PACKAGE_HANDLE_STANDARD_ARGS(FLEX DEFAULT_MSG FLEX_EXECUTABLE)
141 # FindFLEX.cmake ends here