Merge pull request #181 from eirrgang/docs

Update documentation build targets

docs/CMakeLists.txt

@@ -1,23 +1,45 @@
+configure_file(Doxyfile.in Doxyfile)
+
+
+##############################
+# Python package documentation
+##############################
+
 # Dummy output which is never actually produced. Anything that depends on
 # this will always be rebuilt. Ref: https://stackoverflow.com/a/32062884/5351807
 add_custom_command(
-    OUTPUT always_rebuild
-    COMMAND cmake -E echo
+        OUTPUT always_rebuild
+        COMMAND cmake -E echo
 )
 
 add_custom_command(
-    OUTPUT
-    objects.inv
-    DEPENDS
-    always_rebuild
-    COMMAND
-    ${PYTHON_EXECUTABLE} -m sphinx -b html ${CMAKE_CURRENT_SOURCE_DIR} ${CMAKE_CURRENT_BINARY_DIR}
-    COMMENT
-    "Generating documentation with Sphinx"
-    VERBATIM
+        OUTPUT
+        objects.inv
+        DEPENDS
+        always_rebuild
+        COMMAND
+        ${PYTHON_EXECUTABLE} -m sphinx -b html ${CMAKE_CURRENT_SOURCE_DIR} ${CMAKE_CURRENT_BINARY_DIR}
+        COMMENT
+        "Generating documentation with Sphinx"
+        VERBATIM
 )
 
 add_custom_target(
-    docs
-    DEPENDS objects.inv
+        docs
+        DEPENDS objects.inv
 )
+
+################################
+# C++ internal API documentation
+################################
+find_package(Doxygen)
+if (DOXYGEN_FOUND)
+    add_custom_target(cppdocs
+            COMMAND ${DOXYGEN_EXECUTABLE} Doxyfile
+            WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
+            COMMENT "Generating developer documentation"
+            VERBATIM )
+else (DOXYGEN_FOUND)
+    message("Doxygen need to be installed to generate the C++ documentation")
+endif (DOXYGEN_FOUND)
+################################