1# Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
2# file Copyright.txt or https://cmake.org/licensing for details.
3
4#[=======================================================================[.rst:
5FindSWIG
6--------
7
8Find the Simplified Wrapper and Interface Generator (SWIG_) executable.
9
10This module finds an installed SWIG and determines its version.
11
12.. versionadded:: 3.18
13  If a ``COMPONENTS`` or ``OPTIONAL_COMPONENTS`` argument is given to the
14  :command:`find_package` command, it will also determine supported target
15  languages.
16
17.. versionadded:: 3.19
18  When a version is requested, it can be specified as a simple value or as a
19  range. For a detailed description of version range usage and capabilities,
20  refer to the :command:`find_package` command.
21
22The module defines the following variables:
23
24``SWIG_FOUND``
25  Whether SWIG and any required components were found on the system.
26``SWIG_EXECUTABLE``
27  Path to the SWIG executable.
28``SWIG_DIR``
29  Path to the installed SWIG ``Lib`` directory (result of ``swig -swiglib``).
30``SWIG_VERSION``
31  SWIG executable version (result of ``swig -version``).
32``SWIG_<lang>_FOUND``
33  If ``COMPONENTS`` or ``OPTIONAL_COMPONENTS`` are requested, each available
34  target language ``<lang>`` (lowercase) will be set to TRUE.
35
36Any ``COMPONENTS`` given to ``find_package`` should be the names of supported
37target languages as provided to the LANGUAGE argument of ``swig_add_library``,
38such as ``python`` or ``perl5``. Language names *must* be lowercase.
39
40All information is collected from the ``SWIG_EXECUTABLE``, so the version
41to be found can be changed from the command line by means of setting
42``SWIG_EXECUTABLE``.
43
44Example usage requiring SWIG 4.0 or higher and Python language support, with
45optional Fortran support:
46
47.. code-block:: cmake
48
49   find_package(SWIG 4.0 COMPONENTS python OPTIONAL_COMPONENTS fortran)
50   if(SWIG_FOUND)
51     message("SWIG found: ${SWIG_EXECUTABLE}")
52     if(NOT SWIG_fortran_FOUND)
53       message(WARNING "SWIG Fortran bindings cannot be generated")
54     endif()
55   endif()
56
57.. _`SWIG`: http://swig.org
58
59#]=======================================================================]
60
61# compute list of possible names
62unset (_SWIG_NAMES)
63if (SWIG_FIND_VERSION_RANGE)
64  foreach (_SWIG_MAJOR IN ITEMS 4 3 2)
65    if (_SWIG_MAJOR VERSION_GREATER_EQUAL SWIG_FIND_VERSION_MIN_MAJOR
66        AND ((SWIG_FIND_VERSION_RANGE_MAX STREQUAL "INCLUDE" AND _SWIG_MAJOR VERSION_LESS_EQUAL SWIG_FIND_VERSION_MAX)
67        OR (SWIG_FIND_VERSION_RANGE_MAX STREQUAL "EXCLUDE" AND _SWIG_MAJOR VERSION_LESS SWIG_FIND_VERSION_MAX)))
68      list (APPEND _SWIG_NAMES swig${_SWIG_MAJOR}.0)
69    endif()
70  endforeach()
71elseif(SWIG_FIND_VERSION)
72  if (SWIG_FIND_VERSION_EXACT)
73    set(_SWIG_NAMES swig${SWIG_FIND_VERSION_MAJOR}.0)
74  else()
75    foreach (_SWIG_MAJOR IN ITEMS 4 3 2)
76      if (_SWIG_MAJOR VERSION_GREATER_EQUAL SWIG_FIND_VERSION_MAJOR)
77        list (APPEND _SWIG_NAMES swig${_SWIG_MAJOR}.0)
78      endif()
79    endforeach()
80  endif()
81else()
82  set (_SWIG_NAMES swig4.0 swig3.0 swig2.0)
83endif()
84if (NOT _SWIG_NAMES)
85  # try to find any version
86  set (_SWIG_NAMES swig4.0 swig3.0 swig2.0)
87endif()
88
89find_program(SWIG_EXECUTABLE NAMES ${_SWIG_NAMES} swig)
90unset(_SWIG_NAMES)
91
92if(SWIG_EXECUTABLE AND NOT SWIG_DIR)
93  # Find default value for SWIG library directory
94  execute_process(COMMAND "${SWIG_EXECUTABLE}" -swiglib
95    OUTPUT_VARIABLE _swig_output
96    ERROR_VARIABLE _swig_error
97    RESULT_VARIABLE _swig_result)
98
99  if(_swig_result)
100    set(_msg "Command \"${SWIG_EXECUTABLE} -swiglib\" failed with output:\n${_swig_error}")
101    if(SWIG_FIND_REQUIRED)
102      message(SEND_ERROR "${_msg}")
103    else()
104      message(STATUS "${_msg}")
105    endif()
106    unset(_msg)
107  else()
108    string(REGEX REPLACE "[\n\r]+" ";" _SWIG_LIB ${_swig_output})
109  endif()
110
111  # Find SWIG library directory
112  find_path(SWIG_DIR swig.swg PATHS ${_SWIG_LIB} NO_CMAKE_FIND_ROOT_PATH)
113  unset(_SWIG_LIB)
114endif()
115
116if(SWIG_EXECUTABLE AND SWIG_DIR AND NOT SWIG_VERSION)
117  # Determine SWIG version
118  execute_process(COMMAND "${SWIG_EXECUTABLE}" -version
119    OUTPUT_VARIABLE _swig_output
120    ERROR_VARIABLE _swig_output
121    RESULT_VARIABLE _swig_result)
122  if(_swig_result)
123    message(SEND_ERROR "Command \"${SWIG_EXECUTABLE} -version\" failed with output:\n${_swig_output}")
124  else()
125    string(REGEX REPLACE ".*SWIG Version[^0-9.]*\([0-9.]+\).*" "\\1"
126      _swig_output "${_swig_output}")
127    set(SWIG_VERSION ${_swig_output} CACHE STRING "Swig version" FORCE)
128  endif()
129endif()
130
131if(SWIG_EXECUTABLE AND SWIG_FIND_COMPONENTS)
132  execute_process(COMMAND "${SWIG_EXECUTABLE}" -help
133    OUTPUT_VARIABLE _swig_output
134    ERROR_VARIABLE _swig_error
135    RESULT_VARIABLE _swig_result)
136  if(_swig_result)
137    message(SEND_ERROR "Command \"${SWIG_EXECUTABLE} -help\" failed with output:\n${_swig_error}")
138  else()
139    string(REPLACE "\n" ";" _swig_output "${_swig_output}")
140    foreach(SWIG_line IN LISTS _swig_output)
141      if(SWIG_line MATCHES "-([A-Za-z0-9_]+) +- *Generate.*wrappers")
142        set(SWIG_${CMAKE_MATCH_1}_FOUND TRUE)
143      endif()
144    endforeach()
145  endif()
146endif()
147
148unset(_swig_output)
149unset(_swig_error)
150unset(_swig_result)
151
152include(${CMAKE_CURRENT_LIST_DIR}/FindPackageHandleStandardArgs.cmake)
153find_package_handle_standard_args(
154  SWIG HANDLE_COMPONENTS
155  REQUIRED_VARS SWIG_EXECUTABLE SWIG_DIR
156  VERSION_VAR SWIG_VERSION
157  HANDLE_VERSION_RANGE)
158
159if(SWIG_FOUND)
160  set(SWIG_USE_FILE "${CMAKE_CURRENT_LIST_DIR}/UseSWIG.cmake")
161endif()
162
163mark_as_advanced(SWIG_DIR SWIG_VERSION SWIG_EXECUTABLE)
164