CMake installation path consistency (#652)

* Add flag for installation of headers under python include directory

* Allow the disabling of distutils install_headers

CMakeLists.txt

@@ -92,6 +92,11 @@ endforeach()
 set(${PROJECT_NAME}_VERSION ${PYBIND11_VERSION_MAJOR}.${PYBIND11_VERSION_MINOR}.${PYBIND11_VERSION_PATCH})
 set(${PROJECT_NAME}_VERSION ${PYBIND11_VERSION_MAJOR}.${PYBIND11_VERSION_MINOR}.${PYBIND11_VERSION_PATCH})
 message(STATUS "pybind11 v${${PROJECT_NAME}_VERSION}")
 message(STATUS "pybind11 v${${PROJECT_NAME}_VERSION}")
 
 
+option (USE_PYTHON_INCLUDE_DIR "Install pybind11 headers in Python include directory instead of default installation prefix" OFF)
+if (USE_PYTHON_INCLUDE_DIR)
+    file(RELATIVE_PATH CMAKE_INSTALL_INCLUDEDIR ${CMAKE_INSTALL_PREFIX} ${PYTHON_INCLUDE_DIRS})
+endif()
+
 if(NOT (CMAKE_VERSION VERSION_LESS 3.0))  # CMake >= 3.0
 if(NOT (CMAKE_VERSION VERSION_LESS 3.0))  # CMake >= 3.0
   # Build an interface library target:
   # Build an interface library target:
   add_library(module INTERFACE)
   add_library(module INTERFACE)

setup.py

@@ -4,18 +4,14 @@
 
 
 from setuptools import setup
 from setuptools import setup
 from pybind11 import __version__
 from pybind11 import __version__
+import os
 
 
-setup(
-    name='pybind11',
-    version=__version__,
-    description='Seamless operability between C++11 and Python',
-    author='Wenzel Jakob',
-    author_email='wenzel.jakob@epfl.ch',
-    url='https://github.com/wjakob/pybind11',
-    download_url='https://github.com/wjakob/pybind11/tarball/v' + __version__,
-    packages=['pybind11'],
-    license='BSD',
-    headers=[
+# Prevent installation of pybind11 headers by setting
+# PYBIND11_USE_CMAKE.
+if os.environ.get('PYBIND11_USE_CMAKE'):
+    headers = []
+else:
+    headers = [
         'include/pybind11/attr.h',
         'include/pybind11/attr.h',
         'include/pybind11/cast.h',
         'include/pybind11/cast.h',
         'include/pybind11/chrono.h',
         'include/pybind11/chrono.h',
@@ -33,7 +29,19 @@ setup(
         'include/pybind11/stl.h',
         'include/pybind11/stl.h',
         'include/pybind11/stl_bind.h',
         'include/pybind11/stl_bind.h',
         'include/pybind11/typeid.h'
         'include/pybind11/typeid.h'
-    ],
+    ]
+
+setup(
+    name='pybind11',
+    version=__version__,
+    description='Seamless operability between C++11 and Python',
+    author='Wenzel Jakob',
+    author_email='wenzel.jakob@epfl.ch',
+    url='https://github.com/wjakob/pybind11',
+    download_url='https://github.com/wjakob/pybind11/tarball/v' + __version__,
+    packages=['pybind11'],
+    license='BSD',
+    headers=headers,
     classifiers=[
     classifiers=[
         'Development Status :: 5 - Production/Stable',
         'Development Status :: 5 - Production/Stable',
         'Intended Audience :: Developers',
         'Intended Audience :: Developers',