cmake/CMakeParseArguments.cmake

   1 # CMAKE_PARSE_ARGUMENTS(<prefix> <options> <one_value_keywords> <multi_value_keywords> args...)
   2 #
   3 # CMAKE_PARSE_ARGUMENTS() is intended to be used in macros or functions for
   4 # parsing the arguments given to that macro or function.
   5 # It processes the arguments and defines a set of variables which hold the
   6 # values of the respective options.
   7 #
   8 # The <options> argument contains all options for the respective macro,
   9 # i.e. keywords which can be used when calling the macro without any value
  10 # following, like e.g. the OPTIONAL keyword of the install() command.
  11 #
  12 # The <one_value_keywords> argument contains all keywords for this macro
  13 # which are followed by one value, like e.g. DESTINATION keyword of the
  14 # install() command.
  15 #
  16 # The <multi_value_keywords> argument contains all keywords for this macro
  17 # which can be followed by more than one value, like e.g. the TARGETS or
  18 # FILES keywords of the install() command.
  19 #
  20 # When done, CMAKE_PARSE_ARGUMENTS() will have defined for each of the
  21 # keywords listed in <options>, <one_value_keywords> and
  22 # <multi_value_keywords> a variable composed of the given <prefix>
  23 # followed by "_" and the name of the respective keyword.
  24 # These variables will then hold the respective value from the argument list.
  25 # For the <options> keywords this will be TRUE or FALSE.
  26 #
  27 # All remaining arguments are collected in a variable
  28 # <prefix>_UNPARSED_ARGUMENTS, this can be checked afterwards to see whether
  29 # your macro was called with unrecognized parameters.
  30 #
  31 # As an example here a my_install() macro, which takes similar arguments as the
  32 # real install() command:
  33 #
  34 #   function(MY_INSTALL)
  35 #     set(options OPTIONAL FAST)
  36 #     set(oneValueArgs DESTINATION RENAME)
  37 #     set(multiValueArgs TARGETS CONFIGURATIONS)
  38 #     cmake_parse_arguments(MY_INSTALL "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN} )
  39 #     ...
  40 #
  41 # Assume my_install() has been called like this:
  42 #   my_install(TARGETS foo bar DESTINATION bin OPTIONAL blub)
  43 #
  44 # After the cmake_parse_arguments() call the macro will have set the following
  45 # variables:
  46 #   MY_INSTALL_OPTIONAL = TRUE
  47 #   MY_INSTALL_FAST = FALSE (this option was not used when calling my_install()
  48 #   MY_INSTALL_DESTINATION = "bin"
  49 #   MY_INSTALL_RENAME = "" (was not used)
  50 #   MY_INSTALL_TARGETS = "foo;bar"
  51 #   MY_INSTALL_CONFIGURATIONS = "" (was not used)
  52 #   MY_INSTALL_UNPARSED_ARGUMENTS = "blub" (no value expected after "OPTIONAL"
  53 #
  54 # You can the continue and process these variables.
  55 #
  56 # Keywords terminate lists of values, e.g. if directly after a one_value_keyword
  57 # another recognized keyword follows, this is interpreted as the beginning of
  58 # the new option.
  59 # E.g. my_install(TARGETS foo DESTINATION OPTIONAL) would result in
  60 # MY_INSTALL_DESTINATION set to "OPTIONAL", but MY_INSTALL_DESTINATION would
  61 # be empty and MY_INSTALL_OPTIONAL would be set to TRUE therefor.
  62
  63 #=============================================================================
  64 # Copyright 2010 Alexander Neundorf <neundorf@kde.org>
  65 #
  66 # Distributed under the OSI-approved BSD License (the "License");
  67 # see accompanying file Copyright.txt for details.
  68 #
  69 # This software is distributed WITHOUT ANY WARRANTY; without even the
  70 # implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  71 # See the License for more information.
  72 #=============================================================================
  73 # (To distribute this file outside of CMake, substitute the full
  74 #  License text for the above reference.)
  75
  76
  77 if(__CMAKE_PARSE_ARGUMENTS_INCLUDED)
  78   return()
  79 endif()
  80 set(__CMAKE_PARSE_ARGUMENTS_INCLUDED TRUE)
  81
  82
  83 function(CMAKE_PARSE_ARGUMENTS prefix _optionNames _singleArgNames _multiArgNames)
  84   # first set all result variables to empty/FALSE
  85   foreach(arg_name ${_singleArgNames} ${_multiArgNames})
  86     set(${prefix}_${arg_name})
  87   endforeach(arg_name)
  88
  89   foreach(option ${_optionNames})
  90     set(${prefix}_${option} FALSE)
  91   endforeach(option)
  92
  93   set(${prefix}_UNPARSED_ARGUMENTS)
  94
  95   set(insideValues FALSE)
  96   set(currentArgName)
  97
  98   # now iterate over all arguments and fill the result variables
  99   foreach(currentArg ${ARGN})
 100     list(FIND _optionNames "${currentArg}" optionIndex)  # ... then this marks the end of the arguments belonging to this keyword
 101     list(FIND _singleArgNames "${currentArg}" singleArgIndex)  # ... then this marks the end of the arguments belonging to this keyword
 102     list(FIND _multiArgNames "${currentArg}" multiArgIndex)  # ... then this marks the end of the arguments belonging to this keyword
 103
 104     if(${optionIndex} EQUAL -1  AND  ${singleArgIndex} EQUAL -1  AND  ${multiArgIndex} EQUAL -1)
 105       if(insideValues)
 106         if("${insideValues}" STREQUAL "SINGLE")
 107           set(${prefix}_${currentArgName} ${currentArg})
 108           set(insideValues FALSE)
 109         elseif("${insideValues}" STREQUAL "MULTI")
 110           list(APPEND ${prefix}_${currentArgName} ${currentArg})
 111         endif()
 112       else(insideValues)
 113         list(APPEND ${prefix}_UNPARSED_ARGUMENTS ${currentArg})
 114       endif(insideValues)
 115     else()
 116       if(NOT ${optionIndex} EQUAL -1)
 117         set(${prefix}_${currentArg} TRUE)
 118         set(insideValues FALSE)
 119       elseif(NOT ${singleArgIndex} EQUAL -1)
 120         set(currentArgName ${currentArg})
 121         set(${prefix}_${currentArgName})
 122         set(insideValues "SINGLE")
 123       elseif(NOT ${multiArgIndex} EQUAL -1)
 124         set(currentArgName ${currentArg})
 125         set(${prefix}_${currentArgName})
 126         set(insideValues "MULTI")
 127       endif()
 128     endif()
 129
 130   endforeach(currentArg)
 131
 132   # propagate the result variables to the caller:
 133   foreach(arg_name ${_singleArgNames} ${_multiArgNames} ${_optionNames})
 134     set(${prefix}_${arg_name}  ${${prefix}_${arg_name}} PARENT_SCOPE)
 135   endforeach(arg_name)
 136   set(${prefix}_UNPARSED_ARGUMENTS ${${prefix}_UNPARSED_ARGUMENTS} PARENT_SCOPE)
 137
 138 endfunction(CMAKE_PARSE_ARGUMENTS _options _singleArgs _multiArgs)