Build both Python 2 and Python 3 bindings
[profile/ivi/opencv.git] / cmake / OpenCVDetectPython.cmake
index 95a26db..4b71052 100644 (file)
-if(WIN32 AND NOT PYTHON_EXECUTABLE)
-  # search for executable with the same bitness as resulting binaries
-  # standard FindPythonInterp always prefers executable from system path
-  # this is really important because we are using the interpreter for numpy search and for choosing the install location
-  foreach(_CURRENT_VERSION ${Python_ADDITIONAL_VERSIONS} 2.7 "${MIN_VER_PYTHON}")
-    find_host_program(PYTHON_EXECUTABLE
-      NAMES python${_CURRENT_VERSION} python
-      PATHS
-        [HKEY_LOCAL_MACHINE\\\\SOFTWARE\\\\Python\\\\PythonCore\\\\${_CURRENT_VERSION}\\\\InstallPath]
-        [HKEY_CURRENT_USER\\\\SOFTWARE\\\\Python\\\\PythonCore\\\\${_CURRENT_VERSION}\\\\InstallPath]
-      NO_SYSTEM_ENVIRONMENT_PATH
-    )
-  endforeach()
-endif()
-find_host_package(PythonInterp 2.7)
-if(NOT PYTHONINTERP_FOUND)
-find_host_package(PythonInterp "${MIN_VER_PYTHON}")
-endif()
+# Find specified Python version
+# Arguments:
+#   preferred_version (value): Version to check for first
+#   min_version (value): Minimum supported version
+#   library_env (value): Name of Python library ENV variable to check
+#   include_dir_env (value): Name of Python include directory ENV variable to check
+#   found (variable): Set if interpreter found
+#   executable (variable): Output of executable found
+#   version_string (variable): Output of found version
+#   version_major (variable): Output of found major version
+#   version_minor (variable): Output of found minor version
+#   libs_found (variable): Set if libs found
+#   libs_version_string (variable): Output of found libs version
+#   libraries (variable): Output of found Python libraries
+#   library (variable): Output of found Python library
+#   debug_libraries (variable): Output of found Python debug libraries
+#   debug_library (variable): Output of found Python debug library
+#   include_path (variable): Output of found Python include path
+#   include_dir (variable): Output of found Python include dir
+#   include_dir2 (variable): Output of found Python include dir2
+#   packages_path (variable): Output of found Python packages path
+#   numpy_include_dirs (variable): Output of found Python Numpy include dirs
+#   numpy_version (variable): Output of found Python Numpy version
+function(find_python preferred_version min_version library_env include_dir_env
+         found executable version_string version_major version_minor
+         libs_found libs_version_string libraries library debug_libraries
+         debug_library include_path include_dir include_dir2 packages_path
+         numpy_include_dirs numpy_version)
+  if(WIN32 AND NOT ${executable})
+    # search for executable with the same bitness as resulting binaries
+    # standard FindPythonInterp always prefers executable from system path
+    # this is really important because we are using the interpreter for numpy search and for choosing the install location
+    foreach(_CURRENT_VERSION ${Python_ADDITIONAL_VERSIONS} "${preferred_version}" "${min_version}")
+      find_host_program(executable
+        NAMES python${_CURRENT_VERSION} python
+        PATHS
+          [HKEY_LOCAL_MACHINE\\\\SOFTWARE\\\\Python\\\\PythonCore\\\\${_CURRENT_VERSION}\\\\InstallPath]
+          [HKEY_CURRENT_USER\\\\SOFTWARE\\\\Python\\\\PythonCore\\\\${_CURRENT_VERSION}\\\\InstallPath]
+        NO_SYSTEM_ENVIRONMENT_PATH
+      )
+    endforeach()
+  endif()
 
-unset(HAVE_SPHINX CACHE)
+  find_host_package(PythonInterp "${preferred_version}")
+  if(NOT PYTHONINTERP_FOUND)
+    find_host_package(PythonInterp "${min_version}")
+  endif()
 
-if(PYTHONINTERP_FOUND)
-  set(PYTHON_VERSION_MAJOR_MINOR "${PYTHON_VERSION_MAJOR}.${PYTHON_VERSION_MINOR}")
+  if(PYTHONINTERP_FOUND)
+    # Copy outputs
+    set(_found ${PYTHONINTERP_FOUND})
+    set(_executable ${PYTHON_EXECUTABLE})
+    set(_version_string ${PYTHON_VERSION_STRING})
+    set(_version_major ${PYTHON_VERSION_MAJOR})
+    set(_version_minor ${PYTHON_VERSION_MINOR})
+    set(_version_patch ${PYTHON_VERSION_PATCH})
 
-  if(NOT ANDROID AND NOT IOS)
-    ocv_check_environment_variables(PYTHON_LIBRARY PYTHON_INCLUDE_DIR)
-    # not using PYTHON_VERSION_STRING here, because it might not conform to the CMake version format
-    find_host_package(PythonLibs "${PYTHON_VERSION_MAJOR_MINOR}.${PYTHON_VERSION_PATCH}" EXACT)
+    # Clear find_host_package side effects
+    unset(PYTHONINTERP_FOUND)
+    unset(PYTHON_EXECUTABLE CACHE)
+    unset(PYTHON_VERSION_STRING)
+    unset(PYTHON_VERSION_MAJOR)
+    unset(PYTHON_VERSION_MINOR)
+    unset(PYTHON_VERSION_PATCH)
   endif()
 
-  if(NOT ANDROID AND NOT IOS)
-    if(CMAKE_HOST_UNIX)
-      execute_process(COMMAND ${PYTHON_EXECUTABLE} -c "from distutils.sysconfig import *; print(get_python_lib())"
-                      RESULT_VARIABLE PYTHON_CVPY_PROCESS
-                      OUTPUT_VARIABLE PYTHON_STD_PACKAGES_PATH
-                      OUTPUT_STRIP_TRAILING_WHITESPACE)
-      if("${PYTHON_STD_PACKAGES_PATH}" MATCHES "site-packages")
-        set(_PYTHON_PACKAGES_PATH "python${PYTHON_VERSION_MAJOR_MINOR}/site-packages")
-      else() #debian based assumed, install to the dist-packages.
-        set(_PYTHON_PACKAGES_PATH "python${PYTHON_VERSION_MAJOR_MINOR}/dist-packages")
+  if(_found)
+    set(_version_major_minor "${_version_major}.${_version_minor}")
+
+    if(NOT ANDROID AND NOT IOS)
+      ocv_check_environment_variables(${library_env} ${include_dir_env})
+      if(${library})
+          set(PYTHON_LIBRARY "${${library_env}}")
       endif()
-      if(EXISTS "${CMAKE_INSTALL_PREFIX}/lib${LIB_SUFFIX}/${PYTHON_PACKAGES_PATH}")
-        set(_PYTHON_PACKAGES_PATH "lib${LIB_SUFFIX}/${_PYTHON_PACKAGES_PATH}")
-      else()
-        set(_PYTHON_PACKAGES_PATH "lib/${_PYTHON_PACKAGES_PATH}")
+      if(${include_dir})
+          set(PYTHON_INCLUDE_DIR "${${include_dir_env}}")
       endif()
-    elseif(CMAKE_HOST_WIN32)
-      get_filename_component(PYTHON_PATH "${PYTHON_EXECUTABLE}" PATH)
-      file(TO_CMAKE_PATH "${PYTHON_PATH}" PYTHON_PATH)
-      if(NOT EXISTS "${PYTHON_PATH}/Lib/site-packages")
-        unset(PYTHON_PATH)
-        get_filename_component(PYTHON_PATH "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Python\\PythonCore\\${PYTHON_VERSION_MAJOR_MINOR}\\InstallPath]" ABSOLUTE)
-        if(NOT PYTHON_PATH)
-           get_filename_component(PYTHON_PATH "[HKEY_CURRENT_USER\\SOFTWARE\\Python\\PythonCore\\${PYTHON_VERSION_MAJOR_MINOR}\\InstallPath]" ABSOLUTE)
-        endif()
-        file(TO_CMAKE_PATH "${PYTHON_PATH}" PYTHON_PATH)
+
+      # not using _version_string here, because it might not conform to the CMake version format
+      find_host_package(PythonLibs "${_version_major_minor}.${_version_patch}" EXACT)
+
+      if(PYTHONLIBS_FOUND)
+        # Copy outputs
+        set(_libs_found ${PYTHONLIBS_FOUND})
+        set(_libraries ${PYTHON_LIBRARIES})
+        set(_include_path ${PYTHON_INCLUDE_PATH})
+        set(_include_dirs ${PYTHON_INCLUDE_DIRS})
+        set(_debug_libraries ${PYTHON_DEBUG_LIBRARIES})
+        set(_libs_version_string ${PYTHONLIBS_VERSION_STRING})
+        set(_debug_library ${PYTHON_DEBUG_LIBRARY})
+        set(_library ${PYTHON_LIBRARY})
+        set(_library_debug ${PYTHON_LIBRARY_DEBUG})
+        set(_library_release ${PYTHON_LIBRARY_RELEASE})
+        set(_include_dir ${PYTHON_INCLUDE_DIR})
+        set(_include_dir2 ${PYTHON_INCLUDE_DIR2})
+
+        # Clear find_host_package side effects
+        unset(PYTHONLIBS_FOUND)
+        unset(PYTHON_LIBRARIES)
+        unset(PYTHON_INCLUDE_PATH)
+        unset(PYTHON_INCLUDE_DIRS)
+        unset(PYTHON_DEBUG_LIBRARIES)
+        unset(PYTHONLIBS_VERSION_STRING)
+        unset(PYTHON_DEBUG_LIBRARY CACHE)
+        unset(PYTHON_LIBRARY)
+        unset(PYTHON_LIBRARY_DEBUG)
+        unset(PYTHON_LIBRARY_RELEASE)
+        unset(PYTHON_LIBRARY CACHE)
+        unset(PYTHON_LIBRARY_DEBUG CACHE)
+        unset(PYTHON_LIBRARY_RELEASE CACHE)
+        unset(PYTHON_INCLUDE_DIR CACHE)
+        unset(PYTHON_INCLUDE_DIR2 CACHE)
       endif()
-      set(_PYTHON_PACKAGES_PATH "${PYTHON_PATH}/Lib/site-packages")
     endif()
-    SET(PYTHON_PACKAGES_PATH "${_PYTHON_PACKAGES_PATH}" CACHE PATH "Where to install the python packages.")
-
-    if(NOT PYTHON_NUMPY_INCLUDE_DIRS)
-      if(CMAKE_CROSSCOMPILING)
-        message(STATUS "Cannot probe for Python/Numpy support (because we are cross-compiling OpenCV)")
-        message(STATUS "If you want to enable Python/Numpy support, set the following variables:")
-        message(STATUS "  PYTHON_INCLUDE_PATH")
-        message(STATUS "  PYTHON_LIBRARIES")
-        message(STATUS "  PYTHON_NUMPY_INCLUDE_DIRS")
-      else()
-        # Attempt to discover the NumPy include directory. If this succeeds, then build python API with NumPy
-        execute_process(COMMAND "${PYTHON_EXECUTABLE}" -c "import os; os.environ['DISTUTILS_USE_SDK']='1'; import numpy.distutils; print(os.pathsep.join(numpy.distutils.misc_util.get_numpy_include_dirs()))"
-                        RESULT_VARIABLE PYTHON_NUMPY_PROCESS
-                        OUTPUT_VARIABLE PYTHON_NUMPY_INCLUDE_DIRS
+
+    if(NOT ANDROID AND NOT IOS)
+      if(CMAKE_HOST_UNIX)
+        execute_process(COMMAND ${_executable} -c "from distutils.sysconfig import *; print(get_python_lib())"
+                        RESULT_VARIABLE _cvpy_process
+                        OUTPUT_VARIABLE _std_packages_path
                         OUTPUT_STRIP_TRAILING_WHITESPACE)
+        if("${_std_packages_path}" MATCHES "site-packages")
+          set(_packages_path "python${_version_major_minor}/site-packages")
+        else() #debian based assumed, install to the dist-packages.
+          set(_packages_path "python${_version_major_minor}/dist-packages")
+        endif()
+        if(EXISTS "${CMAKE_INSTALL_PREFIX}/lib${LIB_SUFFIX}/${${packages_path}}")
+          set(_packages_path "lib${LIB_SUFFIX}/${_packages_path}")
+        else()
+          set(_packages_path "lib/${_packages_path}")
+        endif()
+      elseif(CMAKE_HOST_WIN32)
+        get_filename_component(_path "${_executable}" PATH)
+        file(TO_CMAKE_PATH "${_path}" _path)
+        if(NOT EXISTS "${_path}/Lib/site-packages")
+          unset(_path)
+          get_filename_component(_path "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Python\\PythonCore\\${_version_major_minor}\\InstallPath]" ABSOLUTE)
+          if(NOT _path)
+             get_filename_component(_path "[HKEY_CURRENT_USER\\SOFTWARE\\Python\\PythonCore\\${_version_major_minor}\\InstallPath]" ABSOLUTE)
+          endif()
+          file(TO_CMAKE_PATH "${_path}" _path)
+        endif()
+        set(_packages_path "${_path}/Lib/site-packages")
+        unset(_path)
+      endif()
+
+      set(_numpy_include_dirs ${${numpy_include_dirs}})
+
+      if(NOT _numpy_include_dirs)
+        if(CMAKE_CROSSCOMPILING)
+          message(STATUS "Cannot probe for Python/Numpy support (because we are cross-compiling OpenCV)")
+          message(STATUS "If you want to enable Python/Numpy support, set the following variables:")
+          message(STATUS "  PYTHON2_INCLUDE_PATH")
+          message(STATUS "  PYTHON2_LIBRARIES")
+          message(STATUS "  PYTHON2_NUMPY_INCLUDE_DIRS")
+          message(STATUS "  PYTHON3_INCLUDE_PATH")
+          message(STATUS "  PYTHON3_LIBRARIES")
+          message(STATUS "  PYTHON3_NUMPY_INCLUDE_DIRS")
+        else()
+          # Attempt to discover the NumPy include directory. If this succeeds, then build python API with NumPy
+          execute_process(COMMAND "${_executable}" -c "import os; os.environ['DISTUTILS_USE_SDK']='1'; import numpy.distutils; print(os.pathsep.join(numpy.distutils.misc_util.get_numpy_include_dirs()))"
+                          RESULT_VARIABLE _numpy_process
+                          OUTPUT_VARIABLE _numpy_include_dirs
+                          OUTPUT_STRIP_TRAILING_WHITESPACE)
 
-        if(NOT PYTHON_NUMPY_PROCESS EQUAL 0)
-          unset(PYTHON_NUMPY_INCLUDE_DIRS)
+          if(NOT _numpy_process EQUAL 0)
+              unset(_numpy_include_dirs)
+          endif()
         endif()
       endif()
-    endif()
 
-    if(PYTHON_NUMPY_INCLUDE_DIRS)
-      file(TO_CMAKE_PATH "${PYTHON_NUMPY_INCLUDE_DIRS}" _PYTHON_NUMPY_INCLUDE_DIRS)
-      set(PYTHON_NUMPY_INCLUDE_DIRS ${_PYTHON_NUMPY_INCLUDE_DIRS} CACHE PATH "Path to numpy headers")
-      if(CMAKE_CROSSCOMPILING)
-        if(NOT PYTHON_NUMPY_VERSION)
-          set(PYTHON_NUMPY_VERSION "undefined - cannot be probed because of the cross-compilation")
+      if(_numpy_include_dirs)
+        file(TO_CMAKE_PATH "${_numpy_include_dirs}" _numpy_include_dirs)
+        if(CMAKE_CROSSCOMPILING)
+          if(NOT _numpy_version)
+            set(_numpy_version "undefined - cannot be probed because of the cross-compilation")
+          endif()
+        else()
+          execute_process(COMMAND "${_executable}" -c "import numpy; print(numpy.version.version)"
+                          RESULT_VARIABLE _numpy_process
+                          OUTPUT_VARIABLE _numpy_version
+                          OUTPUT_STRIP_TRAILING_WHITESPACE)
         endif()
-      else()
-        execute_process(COMMAND "${PYTHON_EXECUTABLE}" -c "import numpy; print(numpy.version.version)"
-                        RESULT_VARIABLE PYTHON_NUMPY_PROCESS
-                        OUTPUT_VARIABLE PYTHON_NUMPY_VERSION
-                        OUTPUT_STRIP_TRAILING_WHITESPACE)
       endif()
-    endif()
-  endif(NOT ANDROID AND NOT IOS)
+    endif(NOT ANDROID AND NOT IOS)
+  endif()
+
+  # Export return values
+  set(${found} "${_found}" PARENT_SCOPE)
+  set(${executable} "${_executable}" CACHE FILEPATH "Path to Python interpretor")
+  set(${version_string} "${_version_string}" PARENT_SCOPE)
+  set(${version_major} "${_version_major}" PARENT_SCOPE)
+  set(${version_minor} "${_version_minor}" PARENT_SCOPE)
+  set(${libs_found} "${_libs_found}" PARENT_SCOPE)
+  set(${libs_version_string} "${_libs_version_string}" PARENT_SCOPE)
+  set(${libraries} "${_libraries}" PARENT_SCOPE)
+  set(${library} "${_library}" CACHE FILEPATH "Path to Python library")
+  set(${debug_libraries} "${_debug_libraries}" PARENT_SCOPE)
+  set(${debug_library} "${_debug_library}" CACHE FILEPATH "Path to Python debug")
+  set(${include_path} "${_include_path}" PARENT_SCOPE)
+  set(${include_dir} "${_include_dir}" CACHE PATH "Python include dir")
+  set(${include_dir2} "${_include_dir2}" CACHE PATH "Python include dir 2")
+  set(${packages_path} "${_packages_path}" CACHE PATH "Where to install the python packages.")
+  set(${numpy_include_dirs} ${_numpy_include_dirs} CACHE PATH "Path to numpy headers")
+  set(${numpy_version} "${_numpy_version}" PARENT_SCOPE)
+endfunction(find_python)
+
+find_python(2.7 "${MIN_VER_PYTHON2}" PYTHON2_LIBRARY PYTHON2_INCLUDE_DIR
+    PYTHON2INTERP_FOUND PYTHON2_EXECUTABLE PYTHON2_VERSION_STRING
+    PYTHON2_VERSION_MAJOR PYTHON2_VERSION_MINOR PYTHON2LIBS_FOUND
+    PYTHON2LIBS_VERSION_STRING PYTHON2_LIBRARIES PYTHON2_LIBRARY
+    PYTHON2_DEBUG_LIBRARIES PYTHON2_LIBRARY_DEBUG PYTHON2_INCLUDE_PATH
+    PYTHON2_INCLUDE_DIR PYTHON2_INCLUDE_DIR2 PYTHON2_PACKAGES_PATH
+    PYTHON2_NUMPY_INCLUDE_DIRS PYTHON2_NUMPY_VERSION)
+
+find_python(3.4 "${MIN_VER_PYTHON3}" PYTHON3_LIBRARY PYTHON3_INCLUDE_DIR
+    PYTHON3INTERP_FOUND PYTHON3_EXECUTABLE PYTHON3_VERSION_STRING
+    PYTHON3_VERSION_MAJOR PYTHON3_VERSION_MINOR PYTHON3LIBS_FOUND
+    PYTHON3LIBS_VERSION_STRING PYTHON3_LIBRARIES PYTHON3_LIBRARY
+    PYTHON3_DEBUG_LIBRARIES PYTHON3_LIBRARY_DEBUG PYTHON3_INCLUDE_PATH
+    PYTHON3_INCLUDE_DIR PYTHON3_INCLUDE_DIR2 PYTHON3_PACKAGES_PATH
+    PYTHON3_NUMPY_INCLUDE_DIRS PYTHON3_NUMPY_VERSION)
+
+# Use Python 2 as default Python interpreter
+if(PYTHON2LIBS_FOUND)
+    set(PYTHON_DEFAULT_AVAILABLE "TRUE")
+    set(PYTHON_DEFAULT_EXECUTABLE "${PYTHON2_EXECUTABLE}")
 endif()
 
+unset(HAVE_SPHINX CACHE)
+
 if(BUILD_DOCS)
   find_host_program(SPHINX_BUILD sphinx-build)
   find_host_program(PLANTUML plantuml)