Fix finding of Boost.Python on Ubuntu

CMakeLists.txt

@@ -29,25 +29,27 @@ macro_optional_find_package( PythonLibs 3.3 REQUIRED )
 macro_log_feature(
     PYTHONLIBS_FOUND
     "Python"
-    "C interface libraries for the Python interpreter."
+    "C interface libraries for the Python 3 interpreter."
     "http://python.org"
-    TRUE ""
-    "Python is used for some Calamares job modules."
+    FALSE "3.3"
+    "Python 3 is used for some Calamares job modules."
 )
-macro_optional_find_package( Boost 1.55.0 COMPONENTS python3 REQUIRED )
+
+include( BoostPython3 )
+find_boost_python3( 1.54.0 ${PYTHONLIBS_VERSION_STRING} CALAMARES_BOOST_PYTHON3_FOUND )
 macro_log_feature(
-    Boost_PYTHON3_FOUND
+    CALAMARES_BOOST_PYTHON3_FOUND
     "Boost.Python"
-    "A C++ library which enables seamless interoperability between C++ and Python."
+    "A C++ library which enables seamless interoperability between C++ and Python 3."
     "http://www.boost.org"
-    TRUE ""
-    "Boost.Python is used for interfacing with Calamares job modules written in Python."
+    FALSE "1.54.0"
+    "Boost.Python is used for interfacing with Calamares job modules written in Python 3."
 )
-if( Boost_PYTHON3_NOTFOUND OR PYTHONLIBS_NOTFOUND )
+
+if ( PYTHONLIBS_NOTFOUND OR NOT CALAMARES_BOOST_PYTHON3_FOUND )
     set( WITH_PYTHON OFF )
 endif()
 
-
 ###
 ### Calamares application info
 ###

CMakeModules/BoostPython3.cmake

@@ -0,0 +1,35 @@
+# On Ubuntu 14.04, the libboost-python1.54-dev package comes with one library
+# for each Python version:
+# libboost_python-py27.so
+# libboost_python-py33.so
+# libboost_python-py34.so
+#
+# Boost upstream however installs Boost.Python3 libboost_python3.so, which is
+# what FindBoost.cmake is looking for. It looks for a library named
+# "libboost_${component}.so".
+#
+# find_boost_python3() tries to find the package with different component names.
+# By default it tries "python3" and "python-py$suffix", where suffix is based on
+# the `python_version` argument. One can supply a custom component name by
+# setting the `CALAMARES_BOOST_PYTHON3_COMPONENT` variable at CMake time.
+
+set( CALAMARES_BOOST_PYTHON3_COMPONENT python3 CACHE STRING
+    "Name of the Boost.Python component. If Boost.Python is installed as
+    libboost_python-foo.so then this variable should be set to 'python-foo'."
+)
+
+macro( find_boost_python3 boost_version python_version found_var )
+    set( ${found_var} OFF )
+
+    # turns "3.4.123abc" into "34"
+    string( REGEX REPLACE "([0-9]+)\\.([0-9]+)\\..*" "\\1\\2" _fbp_python_short_version ${python_version} )
+
+    foreach( _fbp_name ${CALAMARES_BOOST_PYTHON3_COMPONENT} python-py${_fbp_python_short_version} )
+        find_package( Boost ${boost_version} QUIET COMPONENTS ${_fbp_name} )
+        string( TOUPPER ${_fbp_name} _fbp_uc_name )
+        if( Boost_${_fbp_uc_name}_FOUND )
+            set( ${found_var} ON )
+            break()
+        endif()
+    endforeach()
+endmacro()