blob: 20eb7aebb3731d075136827bf40409e55e474dae [file] [log] [blame]
# Distributed under the OSI-approved BSD 3-Clause License. See accompanying
# file Copyright.txt or https://cmake.org/licensing for details.
#.rst:
# FindPythonInterp
# ----------------
#
# Find python interpreter
#
# This module finds if Python interpreter is installed and determines
# where the executables are. This code sets the following variables:
#
# ::
#
# PYTHONINTERP_FOUND - Was the Python executable found
# PYTHON_EXECUTABLE - path to the Python interpreter
#
#
#
# ::
#
# PYTHON_VERSION_STRING - Python version found e.g. 2.5.2
# PYTHON_VERSION_MAJOR - Python major version found e.g. 2
# PYTHON_VERSION_MINOR - Python minor version found e.g. 5
# PYTHON_VERSION_PATCH - Python patch version found e.g. 2
#
#
#
# The Python_ADDITIONAL_VERSIONS variable can be used to specify a list
# of version numbers that should be taken into account when searching
# for Python. You need to set this variable before calling
# find_package(PythonInterp).
#
# If calling both ``find_package(PythonInterp)`` and
# ``find_package(PythonLibs)``, call ``find_package(PythonInterp)`` first to
# get the currently active Python version by default with a consistent version
# of PYTHON_LIBRARIES.
function(determine_python_version exe result)
execute_process(COMMAND "${exe}" -c
"import sys; sys.stdout.write(';'.join([str(x) for x in sys.version_info[:3]]))"
OUTPUT_VARIABLE _VERSION
RESULT_VARIABLE _PYTHON_VERSION_RESULT
ERROR_QUIET)
if(_PYTHON_VERSION_RESULT)
# sys.version predates sys.version_info, so use that
execute_process(COMMAND "${exe}" -c "import sys; sys.stdout.write(sys.version)"
OUTPUT_VARIABLE _VERSION
RESULT_VARIABLE _PYTHON_VERSION_RESULT
ERROR_QUIET)
if(_PYTHON_VERSION_RESULT)
# sys.version was first documented for Python 1.5, so assume
# this is older.
set(ver "1.4")
else()
string(REGEX REPLACE " .*" "" ver "${_VERSION}")
endif()
else()
string(REPLACE ";" "." ver "${_VERSION}")
endif()
set(${result} ${ver} PARENT_SCOPE)
endfunction()
# Find out if the 'python' executable on path has the correct version,
# and choose it if it does. This gives this executable the highest
# priority, which is expected behaviour.
find_program(PYTHON_EXECUTABLE python)
if(NOT (${PYTHON_EXECUTABLE} STREQUAL PYTHON_EXECUTABLE-NOTFOUND))
determine_python_version(${PYTHON_EXECUTABLE} ver)
if(${ver} VERSION_LESS PythonInterp_FIND_VERSION)
# We didn't find the correct version on path, so forget about it
# and continue looking.
unset(PYTHON_EXECUTABLE)
unset(PYTHON_EXECUTABLE CACHE)
endif()
endif()
unset(_Python_NAMES)
set(_PYTHON1_VERSIONS 1.6 1.5)
set(_PYTHON2_VERSIONS 2.7 2.6 2.5 2.4 2.3 2.2 2.1 2.0)
set(_PYTHON3_VERSIONS 3.9 3.8 3.7 3.6 3.5 3.4 3.3 3.2 3.1 3.0)
if(PythonInterp_FIND_VERSION)
if(PythonInterp_FIND_VERSION_COUNT GREATER 1)
set(_PYTHON_FIND_MAJ_MIN "${PythonInterp_FIND_VERSION_MAJOR}.${PythonInterp_FIND_VERSION_MINOR}")
list(APPEND _Python_NAMES
python${_PYTHON_FIND_MAJ_MIN}
python${PythonInterp_FIND_VERSION_MAJOR})
unset(_PYTHON_FIND_OTHER_VERSIONS)
if(NOT PythonInterp_FIND_VERSION_EXACT)
foreach(_PYTHON_V ${_PYTHON${PythonInterp_FIND_VERSION_MAJOR}_VERSIONS})
if(NOT _PYTHON_V VERSION_LESS _PYTHON_FIND_MAJ_MIN)
list(APPEND _PYTHON_FIND_OTHER_VERSIONS ${_PYTHON_V})
endif()
endforeach()
endif()
unset(_PYTHON_FIND_MAJ_MIN)
else()
list(APPEND _Python_NAMES python${PythonInterp_FIND_VERSION_MAJOR})
set(_PYTHON_FIND_OTHER_VERSIONS ${_PYTHON${PythonInterp_FIND_VERSION_MAJOR}_VERSIONS})
endif()
else()
set(_PYTHON_FIND_OTHER_VERSIONS ${_PYTHON3_VERSIONS} ${_PYTHON2_VERSIONS} ${_PYTHON1_VERSIONS})
endif()
find_program(PYTHON_EXECUTABLE NAMES ${_Python_NAMES})
# Set up the versions we know about, in the order we will search. Always add
# the user supplied additional versions to the front.
set(_Python_VERSIONS ${Python_ADDITIONAL_VERSIONS})
# If FindPythonInterp has already found the major and minor version,
# insert that version next to get consistent versions of the interpreter and
# library.
if(DEFINED PYTHONLIBS_VERSION_STRING)
string(REPLACE "." ";" _PYTHONLIBS_VERSION "${PYTHONLIBS_VERSION_STRING}")
list(GET _PYTHONLIBS_VERSION 0 _PYTHONLIBS_VERSION_MAJOR)
list(GET _PYTHONLIBS_VERSION 1 _PYTHONLIBS_VERSION_MINOR)
list(APPEND _Python_VERSIONS ${_PYTHONLIBS_VERSION_MAJOR}.${_PYTHONLIBS_VERSION_MINOR})
endif()
# Search for the current active python version first on Linux, and last on Windows
if(NOT WIN32)
list(APPEND _Python_VERSIONS ";")
endif()
list(APPEND _Python_VERSIONS ${_PYTHON_FIND_OTHER_VERSIONS})
if(WIN32)
list(APPEND _Python_VERSIONS ";")
endif()
unset(_PYTHON_FIND_OTHER_VERSIONS)
unset(_PYTHON1_VERSIONS)
unset(_PYTHON2_VERSIONS)
unset(_PYTHON3_VERSIONS)
# Search for newest python version if python executable isn't found
if(NOT PYTHON_EXECUTABLE)
foreach(_CURRENT_VERSION IN LISTS _Python_VERSIONS)
set(_Python_NAMES python${_CURRENT_VERSION})
if(WIN32)
list(APPEND _Python_NAMES python)
endif()
if(WIN32)
find_program(PYTHON_EXECUTABLE
NAMES ${_Python_NAMES}
HINTS [HKEY_LOCAL_MACHINE\\SOFTWARE\\Python\\PythonCore\\${_CURRENT_VERSION}\\InstallPath]
)
endif()
find_program(PYTHON_EXECUTABLE
NAMES ${_Python_NAMES}
PATHS [HKEY_LOCAL_MACHINE\\SOFTWARE\\Python\\PythonCore\\${_CURRENT_VERSION}\\InstallPath]
)
endforeach()
endif()
# determine python version string
if(PYTHON_EXECUTABLE)
determine_python_version(${PYTHON_EXECUTABLE} res)
set(PYTHON_VERSION_STRING ${res})
if(PYTHON_VERSION_STRING MATCHES "^([0-9]+)\\.([0-9]+)\\.([0-9]+)")
set(PYTHON_VERSION_PATCH "${CMAKE_MATCH_3}")
else()
set(PYTHON_VERSION_PATCH "0")
endif()
set(PYTHON_VERSION_MAJOR "${CMAKE_MATCH_1}")
set(PYTHON_VERSION_MINOR "${CMAKE_MATCH_2}")
endif()
include(FindPackageHandleStandardArgs)
FIND_PACKAGE_HANDLE_STANDARD_ARGS(PythonInterp REQUIRED_VARS PYTHON_EXECUTABLE VERSION_VAR PYTHON_VERSION_STRING)
mark_as_advanced(PYTHON_EXECUTABLE)