Minimal Doxygen setup

Author: dbaston

CMakeLists.txt

@@ -124,3 +124,27 @@ target_link_libraries(
             ${GEOS_LIBRARY}
 )
 
+# Doxygen configuration from https://vicrucann.github.io/tutorials/quick-cmake-doxygen/
+# first we can indicate the documentation build as an option and set it to ON by default
+option(BUILD_DOC "Build documentation" ON)
+
+# check if Doxygen is installed
+find_package(Doxygen)
+if (DOXYGEN_FOUND)
+    # set input and output files
+    set(DOXYGEN_IN ${CMAKE_SOURCE_DIR}/docs/Doxyfile.in)
+    set(DOXYGEN_OUT ${CMAKE_CURRENT_BINARY_DIR}/Doxyfile)
+
+    # request to configure the file
+    configure_file(${DOXYGEN_IN} ${DOXYGEN_OUT} @ONLY)
+    message("Doxygen build started")
+
+    # note the option ALL which allows to build the docs together with the application
+    add_custom_target( doc_doxygen ALL
+            COMMAND ${DOXYGEN_EXECUTABLE} ${DOXYGEN_OUT}
+            WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
+            COMMENT "Generating API documentation with Doxygen"
+            VERBATIM )
+else (DOXYGEN_FOUND)
+    message("Doxygen need to be installed to generate the doxygen documentation")
+endif (DOXYGEN_FOUND)