Create aliases for probed variables

Headers from other libraries (notably DUNE) require definitions of
other variables than our probe process set (e.g. HAVE_UMFPACK instead
of HAVE_SUITESPARSE_UMFPACK_H). This module sets those aliases for
compatibility.

cmake/Modules/OpmAliases.cmake

@@ -0,0 +1,24 @@
+# - Alias probed variables for compatibility with DUNE buildsystem
+#
+# DUNE build system sets some variables which have different names
+# in the CMake modules we are using; this module set those variable
+# so they can be exported to config.h visible to DUNE headers
+
+function (set_aliases)
+  # hardcoded list of "dune-var opm-var" pairs, where the components
+  # are separated by space
+  set (aliases
+	)
+  foreach (alias IN LISTS aliases)
+	# convert entry "X Y" into a list "X;Y", then pick apart
+	string (REGEX REPLACE "\ +" ";" tuple "${alias}")
+	list (GET tuple 0 var)	
+	list (GET tuple 1 name)
+
+	# write this alias to cache
+	set (${var} ${${name}} PARENT_SCOPE)
+  endforeach (alias)
+endfunction (set_aliases)
+
+# always call this when the module is imported
+set_aliases ()

cmake/Modules/OpmLibMain.cmake

@@ -89,6 +89,9 @@ endif (COMMAND prereqs_hook)
 include (OpmFind)
 find_and_append_package_list_to (${project} ${${project}_DEPS})
 
+# set aliases to probed variables
+include (OpmAliases)
+
 # remove the dependency on the testing framework from the main library;
 # it is not possible to query for Boost twice with different components.
 list (REMOVE_ITEM "${project}_LIBRARIES" "${Boost_UNIT_TEST_FRAMEWORK_LIBRARY}")

cmake/OPM-CMake.md

@@ -423,6 +423,12 @@ Wrapper script which emulates an autotools front-end, making the build
 system usable with dunecontrol. There is one in the project root directory
 which just forwards everything to the main script in `cmake/Scripts`.
 
+<tr>
+<td>	OpmAliases
+<td>
+Copy variables which are probed by our find modules to the names which
+are expected by DUNE.
+
 <tr>
 <td>	OpmCompile
 <td>