cmake: add build counter

Signed-off-by: Janusz Jankowski <janusz.jankowski@linux.intel.com>

CMakeLists.txt

@@ -37,9 +37,10 @@ include(scripts/cmake/misc.cmake)
 
 project(SOF C ASM)
 
-# intended to be used where PROJECT_SOURCE_DIR is not set
+# intended to be used where PROJECT_* variables are not set
 # for example in standalone scripts like version.cmake
 set(SOF_ROOT_SOURCE_DIRECTORY "${PROJECT_SOURCE_DIR}")
+set(SOF_ROOT_BINARY_DIRECTORY "${PROJECT_BINARY_DIR}")
 
 # most of other options are set on per-arch and per-target basis
 set(CMAKE_ASM_FLAGS -DASSEMBLY)
@@ -126,6 +127,8 @@ target_link_libraries(sof sof_options)
 target_link_libraries(sof sof_ld_scripts)
 target_link_libraries(sof sof_ld_flags)
 
+sof_add_build_counter_rule()
+
 add_subdirectory(src)
 
 target_link_libraries(sof sof_lib)

scripts/cmake/version-build-counter.cmake

@@ -0,0 +1,37 @@
+# Implements build counter and adds it as post-build action for sof
+
+cmake_minimum_required(VERSION 3.10)
+
+set(VERSION_BUILD_COUNTER_CMAKE_PATH ${CMAKE_CURRENT_LIST_DIR}/version-build-counter.cmake)
+
+set(BUILD_COUNTER_PATH "${SOF_ROOT_BINARY_DIRECTORY}/.build")
+
+if(NOT EXISTS "${BUILD_COUNTER_PATH}")
+	file(WRITE "${BUILD_COUNTER_PATH}" "1")
+endif()
+
+file(READ "${BUILD_COUNTER_PATH}" SOF_BUILD)
+
+if(NOT SOF_BUILD MATCHES "^[0-9]+$")
+	message(WARNING "Invalid SOF_BUILD - setting to 1")
+	set(SOF_BUILD 1)
+endif()
+
+function(sof_add_build_counter_rule)
+	add_custom_command(
+		TARGET sof
+		POST_BUILD
+		COMMAND ${CMAKE_COMMAND}
+			-DSOF_ROOT_BINARY_DIRECTORY=${SOF_ROOT_BINARY_DIRECTORY}
+			-DBUILD_COUNTER_INCREMENT=ON
+			-P ${VERSION_BUILD_COUNTER_CMAKE_PATH}
+		COMMENT "Incrementing build number in ${BUILD_COUNTER_PATH}"
+		VERBATIM
+		USES_TERMINAL
+	)
+endfunction()
+
+if(BUILD_COUNTER_INCREMENT)
+	MATH(EXPR NEXT_SOF_BUILD "(${SOF_BUILD} + 1) % 65536")
+	file(WRITE "${BUILD_COUNTER_PATH}" ${NEXT_SOF_BUILD})
+endif()

scripts/cmake/version.cmake

@@ -50,8 +50,8 @@ if(NOT SOF_TAG)
 	set(SOF_TAG 0)
 endif()
 
-# TODO
-set(SOF_BUILD 0)
+# for SOF_BUILD
+include(${CMAKE_CURRENT_LIST_DIR}/version-build-counter.cmake)
 
 function(sof_check_version_h)
 	string(CONCAT header_content
@@ -82,6 +82,7 @@ if("${CMAKE_SCRIPT_MODE_FILE}" STREQUAL "")
 		COMMAND ${CMAKE_COMMAND}
 			-DVERSION_H_PATH=${VERSION_H_PATH}
 			-DSOF_ROOT_SOURCE_DIRECTORY=${SOF_ROOT_SOURCE_DIRECTORY}
+			-DSOF_ROOT_BINARY_DIRECTORY=${SOF_ROOT_BINARY_DIRECTORY}
 			-P ${VERSION_CMAKE_PATH}
 		COMMENT "Checking ${VERSION_H_PATH}"
 		VERBATIM