reorganize cmake option defaults, cmake flags, macros

cmake c and cxx flags include _CRT_SECURE_NO_WARNINGS to avoid a lot msdn warnings
check_target macro is a helper to reduce number of lines in include/CMakeLists.txt

CMakeLists.txt

@@ -9,21 +9,21 @@ endif()
 
 set(CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/find_scripts;${CMAKE_MODULE_PATH}")
 
-#TODO
-option(WITH_CAIRO "Build with cairo support ." ON)
+set(default_option_enabled ON)
 if(WIN32)
-option(WITH_X11 "Build with X11 support ." OFF)
-else()
-option(WITH_X11 "Build with X11 support ." ON)
+  set(default_option_enabled OFF)
 endif()
+
+option(WITH_CAIRO "Build with cairo support ." ON)
+option(WITH_X11 "Build with X11 support ." ${default_option_enabled})
 option(WITH_OPENGL "Build with opengl support ." ON)
 option(WITH_SQLITE "enable sqlite support" ON)
 option(WITH_POSTGRES "enable postgres support" OFF)
-option(WITH_NLS "enable sqlite support" ON)
+option(WITH_NLS "enable sqlite support" ${default_option_enabled})
 option(WITH_BZLIB "enable sqlite support" ON)
 option(WITH_BLAS "enable sqlite support" ON)
 option(WITH_LAPACK "enable sqlite support" ON)
-
+option(WITH_LARGEFILES "enable largefile support" ${default_option_enabled})
 if(APPLE)
   if(POLICY CMP0042)
     cmake_policy(SET CMP0042 NEW)
@@ -50,11 +50,16 @@ set(BUILD_ARCH "x86_64")
 file(STRINGS "include/VERSION" GRASS_VERSION_STRINGS)
 list(LENGTH GRASS_VERSION_STRINGS GRASS_VERSION_FILE_LENGTH)
 
-if(WIN32)
-set(CMAKE_C_FLAGS "/D_CRT_SECURE_NO_WARNINGS")
-if(CMAKE_C_FLAGS)
-set(CMAKE_C_FLAGS "${GRASS_C_FLAGS} ${CMAKE_C_FLAGS}")
-endif()
+if(MSVC)
+  set(GRASS_C_FLAGS "/D_CRT_SECURE_NO_WARNINGS")
+  if(CMAKE_C_FLAGS)
+    set(CMAKE_C_FLAGS "${GRASS_C_FLAGS} ${CMAKE_C_FLAGS}")
+  endif()
+
+  set(GRASS_CXX_FLAGS "/D_CRT_SECURE_NO_WARNINGS")
+  if(CMAKE_CXX_FLAGS)
+    set(CMAKE_CXX_FLAGS "${GRASS_CXX_FLAGS} ${CMAKE_CXX_FLAGS}")
+  endif()
 endif()
 
 if(GRASS_VERSION_FILE_LENGTH LESS 3 )
@@ -227,6 +232,14 @@ macro(build_program_in_subdir dir_name)
   endif()
 endmacro()
 
+macro(check_target target_name have_define_var)
+set(${have_define_var} 0)
+if(TARGET ${target_name})
+  message(STATUS "${target_name} package found. Setting ${have_define_var} to 1")
+  set(${have_define_var} 1)
+endif()
+endmacro()
+
 add_subdirectory(thirdparty)
 
 include(cmake/scripts.cmake)