Merge pull request cpp-best-practices#62 from patrickelectric/add_cache

cmake: Add Cache file

Author: lefticus

CMakeLists.txt

@@ -18,6 +18,9 @@ endif()
 # Link this 'library' to use the warnings specified in CompilerWarnings.cmake
 add_library(project_warnings INTERFACE)
 
+# enable cache system
+include(cmake/Cache.cmake)
+
 # standard compiler warnings
 include(cmake/CompilerWarnings.cmake)
 set_project_warnings(project_warnings)

cmake/Cache.cmake

@@ -0,0 +1,21 @@
+option(ENABLE_CACHE "Enable cache if available" ON)
+if(NOT ENABLE_CACHE)
+ return()
+endif()
+
+set(CACHE_OPTION "ccache" CACHE STRING "Compiler cache to be used")
+set(CACHE_OPTION_VALUES "ccache" "sccache")
+set_property(CACHE CACHE_OPTION PROPERTY STRINGS ${CACHE_OPTION_VALUES})
+list(FIND CACHE_OPTION_VALUES ${CACHE_OPTION} CACHE_OPTION_INDEX)
+
+if(${CACHE_OPTION_INDEX} EQUAL -1)
+ message(STATUS "Using custom compiler cache system: '${CACHE_OPTION}', explicitly supported entries are ${CACHE_OPTION_VALUES}")
+endif()
+
+find_program(CACHE_BINARY ${CACHE_OPTION})
+if(CACHE_BINARY)
+ message(STATUS "${CACHE_OPTION} found and enabled")
+ set(CMAKE_CXX_COMPILER_LAUNCHER ${CACHE_BINARY})
+else()
+ message(WARNING "${CACHE_OPTION} is enabled but was not found. Not using it")
+endif()

cmake/StandardProjectSettings.cmake

@@ -10,14 +10,6 @@ if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
  "MinSizeRel" "RelWithDebInfo")
 endif()
 
-find_program(CCACHE ccache)
-if(CCACHE)
- message("using ccache")
- set(CMAKE_CXX_COMPILER_LAUNCHER ${CCACHE})
-else()
- message("ccache not found cannot use")
-endif()
-
 # Generate compile_commands.json to make it easier to work with clang based
 # tools
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)