cmake: updated backends build

src/backends/CMakeLists.txt

@@ -1,9 +1,33 @@
 colormsg(_HIBLUE_ "Configuring SOCI database backends:")
 
-# TODO: Scan and add directories automatically --mloskot
-add_subdirectory(empty)
-add_subdirectory(mysql)
-add_subdirectory(odbc)
-add_subdirectory(oracle)
-add_subdirectory(postgresql)
-add_subdirectory(sqlite3)
+# First, we'll investigate what can be found from database engines
+foreach(dep ${SOCI_BACKENDS_DB_DEPENDENCIES})
+	string(TOUPPER ${dep} depUP)
+	find_package(${dep})
+	if(${dep}_FOUND OR ${depUP}_FOUND)
+		set(${depUP}_FOUND ON)
+	else()
+		set(${depUP}_FOUND OFF)
+	endif()
+endforeach()
+
+# get all files in backends
+file(GLOB backend_dirs RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} *)
+
+# empty backend always on by default
+set(EMPTY_FOUND ON)
+
+# enable only found backends
+foreach(dir ${backend_dirs})
+	if(IS_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/${dir})
+		if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${dir}/CMakeLists.txt)
+			string(TOUPPER ${dir} dirUP)
+			if(${dirUP}_FOUND)
+				add_subdirectory(${dir})
+				message("added backend: ${dir}")
+			endif()
+		endif()
+	endif()
+endforeach()
+
+message(STATUS "")

src/cmake/SociDependencies.cmake

@@ -19,14 +19,17 @@
 #
 # List of SOCI dependncies
 #
-set(SOCI_BACKENDS_ALL_DEPENDENCIES
-  Boost
+set(SOCI_BACKENDS_DB_DEPENDENCIES
   MySQL
   ODBC
   Oracle
   PostgreSQL
   SQLite3)
 
+set(SOCI_BACKENDS_ALL_DEPENDENCIES
+  Boost
+  ${SOCI_BACKENDS_DB_DEPENDENCIES})
+
 #
 # Perform checks
 #