+# - Find python libraries
+# This module finds the libraries corresponding to the Python interpreter
+# FindPythonInterp provides.
+# This code sets the following variables:
+#
+# PYTHONLIBS_FOUND - have the Python libs been found
+# PYTHON_PREFIX - path to the Python installation
+# PYTHON_LIBRARIES - path to the python library
+# PYTHON_INCLUDE_DIRS - path to where Python.h is found
+# PYTHON_MODULE_EXTENSION - lib extension, e.g. '.so' or '.pyd'
+# PYTHON_MODULE_PREFIX - lib name prefix: usually an empty string
+# PYTHON_SITE_PACKAGES - path to installation site-packages
+# PYTHON_IS_DEBUG - whether the Python interpreter is a debug build
+#
+# Thanks to talljimbo for the patch adding the 'LDVERSION' config
+# variable usage.
+
+#=============================================================================
+# Copyright 2001-2009 Kitware, Inc.
+# Copyright 2012 Continuum Analytics, Inc.
+#
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+#
+# * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#
+# * Redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution.
+#
+# * Neither the names of Kitware, Inc., the Insight Software Consortium,
+# nor the names of their contributors may be used to endorse or promote
+# products derived from this software without specific prior written
+# permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#=============================================================================
+
+# Checking for the extension makes sure that `LibsNew` was found and not just `Libs`.
+if(PYTHONLIBS_FOUND AND PYTHON_MODULE_EXTENSION)
+ return()
+endif()
+
+# Use the Python interpreter to find the libs.
+if(PythonLibsNew_FIND_REQUIRED)
+ find_package(PythonInterp ${PythonLibsNew_FIND_VERSION} REQUIRED)
+else()
+ find_package(PythonInterp ${PythonLibsNew_FIND_VERSION})
+endif()
+
+if(NOT PYTHONINTERP_FOUND)
+ set(PYTHONLIBS_FOUND FALSE)
+ return()
+endif()
+
+# According to http://stackoverflow.com/questions/646518/python-how-to-detect-debug-interpreter
+# testing whether sys has the gettotalrefcount function is a reliable, cross-platform
+# way to detect a CPython debug interpreter.
+#
+# The library suffix is from the config var LDVERSION sometimes, otherwise
+# VERSION. VERSION will typically be like "2.7" on unix, and "27" on windows.
+execute_process(COMMAND "${PYTHON_EXECUTABLE}" "-c"
+ "from distutils import sysconfig as s;import sys;import struct;
+print('.'.join(str(v) for v in sys.version_info));
+print(sys.prefix);
+print(s.get_python_inc(plat_specific=True));
+print(s.get_python_lib(plat_specific=True));
+print(s.get_config_var('SO'));
+print(hasattr(sys, 'gettotalrefcount')+0);
+print(struct.calcsize('@P'));
+print(s.get_config_var('LDVERSION') or s.get_config_var('VERSION'));
+print(s.get_config_var('LIBDIR') or '');
+print(s.get_config_var('MULTIARCH') or '');
+"
+ RESULT_VARIABLE _PYTHON_SUCCESS
+ OUTPUT_VARIABLE _PYTHON_VALUES
+ ERROR_VARIABLE _PYTHON_ERROR_VALUE)
+
+if(NOT _PYTHON_SUCCESS MATCHES 0)
+ if(PythonLibsNew_FIND_REQUIRED)
+ message(FATAL_ERROR
+ "Python config failure:\n${_PYTHON_ERROR_VALUE}")
+ endif()
+ set(PYTHONLIBS_FOUND FALSE)
+ return()
+endif()
+
+# Convert the process output into a list
+string(REGEX REPLACE ";" "\\\\;" _PYTHON_VALUES ${_PYTHON_VALUES})
+string(REGEX REPLACE "\n" ";" _PYTHON_VALUES ${_PYTHON_VALUES})
+list(GET _PYTHON_VALUES 0 _PYTHON_VERSION_LIST)
+list(GET _PYTHON_VALUES 1 PYTHON_PREFIX)
+list(GET _PYTHON_VALUES 2 PYTHON_INCLUDE_DIR)
+list(GET _PYTHON_VALUES 3 PYTHON_SITE_PACKAGES)
+list(GET _PYTHON_VALUES 4 PYTHON_MODULE_EXTENSION)
+list(GET _PYTHON_VALUES 5 PYTHON_IS_DEBUG)
+list(GET _PYTHON_VALUES 6 PYTHON_SIZEOF_VOID_P)
+list(GET _PYTHON_VALUES 7 PYTHON_LIBRARY_SUFFIX)
+list(GET _PYTHON_VALUES 8 PYTHON_LIBDIR)
+list(GET _PYTHON_VALUES 9 PYTHON_MULTIARCH)
+
+# Make sure the Python has the same pointer-size as the chosen compiler
+# Skip if CMAKE_SIZEOF_VOID_P is not defined
+if(CMAKE_SIZEOF_VOID_P AND (NOT "${PYTHON_SIZEOF_VOID_P}" STREQUAL "${CMAKE_SIZEOF_VOID_P}"))
+ if(PythonLibsNew_FIND_REQUIRED)
+ math(EXPR _PYTHON_BITS "${PYTHON_SIZEOF_VOID_P} * 8")
+ math(EXPR _CMAKE_BITS "${CMAKE_SIZEOF_VOID_P} * 8")
+ message(FATAL_ERROR
+ "Python config failure: Python is ${_PYTHON_BITS}-bit, "
+ "chosen compiler is ${_CMAKE_BITS}-bit")
+ endif()
+ set(PYTHONLIBS_FOUND FALSE)
+ return()
+endif()
+
+# The built-in FindPython didn't always give the version numbers
+string(REGEX REPLACE "\\." ";" _PYTHON_VERSION_LIST ${_PYTHON_VERSION_LIST})
+list(GET _PYTHON_VERSION_LIST 0 PYTHON_VERSION_MAJOR)
+list(GET _PYTHON_VERSION_LIST 1 PYTHON_VERSION_MINOR)
+list(GET _PYTHON_VERSION_LIST 2 PYTHON_VERSION_PATCH)
+
+# Make sure all directory separators are '/'
+string(REGEX REPLACE "\\\\" "/" PYTHON_PREFIX ${PYTHON_PREFIX})
+string(REGEX REPLACE "\\\\" "/" PYTHON_INCLUDE_DIR ${PYTHON_INCLUDE_DIR})
+string(REGEX REPLACE "\\\\" "/" PYTHON_SITE_PACKAGES ${PYTHON_SITE_PACKAGES})
+
+if(CMAKE_HOST_WIN32)
+ set(PYTHON_LIBRARY
+ "${PYTHON_PREFIX}/libs/Python${PYTHON_LIBRARY_SUFFIX}.lib")
+
+ # when run in a venv, PYTHON_PREFIX points to it. But the libraries remain in the
+ # original python installation. They may be found relative to PYTHON_INCLUDE_DIR.
+ if(NOT EXISTS "${PYTHON_LIBRARY}")
+ get_filename_component(_PYTHON_ROOT ${PYTHON_INCLUDE_DIR} DIRECTORY)
+ set(PYTHON_LIBRARY
+ "${_PYTHON_ROOT}/libs/Python${PYTHON_LIBRARY_SUFFIX}.lib")
+ endif()
+
+ # raise an error if the python libs are still not found.
+ if(NOT EXISTS "${PYTHON_LIBRARY}")
+ message(FATAL_ERROR "Python libraries not found")
+ endif()
+
+else()
+ if(PYTHON_MULTIARCH)
+ set(_PYTHON_LIBS_SEARCH "${PYTHON_LIBDIR}/${PYTHON_MULTIARCH}" "${PYTHON_LIBDIR}")
+ else()
+ set(_PYTHON_LIBS_SEARCH "${PYTHON_LIBDIR}")
+ endif()
+ #message(STATUS "Searching for Python libs in ${_PYTHON_LIBS_SEARCH}")
+ # Probably this needs to be more involved. It would be nice if the config
+ # information the python interpreter itself gave us were more complete.
+ find_library(PYTHON_LIBRARY
+ NAMES "python${PYTHON_LIBRARY_SUFFIX}"
+ PATHS ${_PYTHON_LIBS_SEARCH}
+ NO_DEFAULT_PATH)
+
+ # If all else fails, just set the name/version and let the linker figure out the path.
+ if(NOT PYTHON_LIBRARY)
+ set(PYTHON_LIBRARY python${PYTHON_LIBRARY_SUFFIX})
+ endif()
+endif()
+
+MARK_AS_ADVANCED(
+ PYTHON_LIBRARY
+ PYTHON_INCLUDE_DIR
+)
+
+# We use PYTHON_INCLUDE_DIR, PYTHON_LIBRARY and PYTHON_DEBUG_LIBRARY for the
+# cache entries because they are meant to specify the location of a single
+# library. We now set the variables listed by the documentation for this
+# module.
+SET(PYTHON_INCLUDE_DIRS "${PYTHON_INCLUDE_DIR}")
+SET(PYTHON_LIBRARIES "${PYTHON_LIBRARY}")
+SET(PYTHON_DEBUG_LIBRARIES "${PYTHON_DEBUG_LIBRARY}")
+
+find_package_message(PYTHON
+ "Found PythonLibs: ${PYTHON_LIBRARY}"
+ "${PYTHON_EXECUTABLE}${PYTHON_VERSION}")
+
+set(PYTHONLIBS_FOUND TRUE)
