auto-clone C/C, if possible

CMakeLists.txt

@@ -115,6 +115,11 @@ FOREACH(_base
   ENDIF()
 ENDFOREACH()
 
+FOREACH(tool gtar tar git)
+ STRING(TOUPPER ${tool}  TOOL)
+ FIND_PROGRAM(${TOOL}_EXECUTABLE ${tool} DOC "path to the executable")
+ MARK_AS_ADVANCED(${TOOL}_EXECUTABLE)
+ENDFOREACH()
 
 # Following autotools tradition, add preprocessor definitions
 # specified in environment variable CPPFLAGS

cmake/mariadb_connector_c.cmake

+IF(NOT EXISTS ${CMAKE_SOURCE_DIR}/libmariadb/CMakeLists.txt AND GIT_EXECUTABLE)
+  EXECUTE_PROCESS(COMMAND "${GIT_EXECUTABLE}" submodule init
+                  WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}")
+  EXECUTE_PROCESS(COMMAND "${GIT_EXECUTABLE}" submodule update
+                  WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}")
+ENDIF()
+IF(NOT EXISTS ${CMAKE_SOURCE_DIR}/libmariadb/CMakeLists.txt)
+  MESSAGE(FATAL_ERROR "No MariaDB Connector/C! Run
+    git submodule init
+    git submodule update
+Then restart the build.
+")
+ENDIF()
+
 SET(OPT CONC_)
 
 IF (CMAKE_BUILD_TYPE STREQUAL "Debug")

sql/CMakeLists.txt

@@ -320,12 +320,6 @@ IF(WIN32 OR HAVE_DLOPEN AND NOT DISABLE_SHARED)
   ENDIF()
 ENDIF()
 
-FOREACH(tool gtar tar git)
- STRING(TOUPPER ${tool}  TOOL)
- FIND_PROGRAM(${TOOL}_EXECUTABLE ${tool} DOC "path to the executable")
- MARK_AS_ADVANCED(${TOOL}_EXECUTABLE)
-ENDFOREACH()
-
 CONFIGURE_FILE(
   ${CMAKE_SOURCE_DIR}/cmake/make_dist.cmake.in
   ${CMAKE_BINARY_DIR}/make_dist.cmake @ONLY)