add git info to nabla

Author: tad1

cmake/scripts/nbl/gitInfo.cmake

@@ -0,0 +1,18 @@
+# A configure-time and build-time script, that produces source with current git commit info
+# required variables: GIT_EXECUTABLE, WORKING_DIRECTORY, INPUT_FILE, OUTPUT_FILE
+
+execute_process( COMMAND ${GIT_EXECUTABLE} log -1 --format=%H
+    WORKING_DIRECTORY ${WORKING_DIRECTORY}
+    OUTPUT_VARIABLE NBL_GIT_COMMIT_HASH
+    OUTPUT_STRIP_TRAILING_WHITESPACE
+)
+
+execute_process( COMMAND ${GIT_EXECUTABLE} log -1 --format=%h
+    WORKING_DIRECTORY ${WORKING_DIRECTORY}
+    OUTPUT_VARIABLE NBL_GIT_COMMIT_SHORT_HASH
+    OUTPUT_STRIP_TRAILING_WHITESPACE
+)
+
+# since CMake 3.10.3: "The generated file is modified and its timestamp updated on subsequent cmake runs only if its content is changed."
+# we can spam this each run/build
+configure_file("${INPUT_FILE}" "${OUTPUT_FILE}")

include/nabla.h

@@ -17,6 +17,9 @@
 #ifndef __NABLA_H_INCLUDED__
 #define __NABLA_H_INCLUDED__
 
+// meta info
+#include "nbl/git_info.h"
+
 // core lib
 #include "nbl/core/declarations.h"
 

include/nbl/git_info.h

@@ -0,0 +1,12 @@
+#ifndef __GIT_INFO_H_INCLUDED__
+#define __GIT_INFO_H_INCLUDED__
+
+namespace nbl {
+	struct GitInfo {
+		const char* CommitHash;
+		const char* ShortCommitHash;
+	};
+	extern const GitInfo git;
+}
+
+#endif // __GIT_INFO_H_INCLUDED__

src/nbl/CMakeLists.txt

@@ -284,13 +284,18 @@ set(NBL_SCENE_SOURCES
 	${NBL_ROOT_PATH}/src/nbl/scene/ITransformTree.cpp
 )
 
+set(NBL_GENERATED_SOURCES
+	${CMAKE_BINARY_DIR}/src/nbl/git_info.cpp
+)
+
 set(NABLA_SRCS_COMMON
 	${NBL_CORE_SOURCES}
 	${NBL_SYSTEM_SOURCES}
 	${NBL_UI_SOURCES}
 	${NBL_ASSET_SOURCES}
 	${NBL_VIDEO_SOURCES}
 	${NBL_SCENE_SOURCES}
+	${NBL_GENERATED_SOURCES}
 )
 
 if(MSVC)
@@ -653,6 +658,20 @@ glue_source_definitions(Nabla _NBL_SOURCE_DEFINITIONS_)
 set(_NBL_DEFINE_FILE_WRAPPER_ ${CMAKE_CURRENT_BINARY_DIR}/include/define.h)
 write_source_definitions("${_NBL_DEFINE_FILE_WRAPPER_}" "${_NBL_SOURCE_DEFINITIONS_}")
 
+add_custom_target(CheckGit COMMAND ${CMAKE_COMMAND}
+	-DWORKING_DIRECTORY:PATH=${NBL_ROOT_PATH}
+	-DGIT_EXECUTABLE:PATH=${GIT_EXECUTABLE}
+	-DINPUT_FILE:PATH="${NBL_ROOT_PATH}/src/nbl/git_info.cpp.in"
+	-DOUTPUT_FILE:PATH="${CMAKE_BINARY_DIR}/src/nbl/git_info.cpp"
+	-P ${NBL_ROOT_PATH}/cmake/scripts/nbl/gitInfo.cmake
+	BYPRODUCTS ${CMAKE_BINARY_DIR}/src/nbl/git_info.cpp
+)
+
+set(INPUT_FILE "${NBL_ROOT_PATH}/src/nbl/git_info.cpp.in")
+set(OUTPUT_FILE "${CMAKE_BINARY_DIR}/src/nbl/git_info.cpp")
+set(WORKING_DIRECTORY ${NBL_ROOT_PATH})
+include("${NBL_ROOT_PATH}/cmake/scripts/nbl/gitInfo.cmake")
+
 #on MSVC it won't compile without this option!
 if (MSVC)
 	target_compile_options(Nabla PUBLIC /bigobj)

src/nbl/git_info.cpp.in

@@ -0,0 +1,9 @@
+#include "nbl/git_info.h"
+
+namespace nbl
+{
+	const GitInfo git = {
+        .CommitHash = "@NBL_GIT_COMMIT_HASH@",
+		.ShortCommitHash = "@NBL_GIT_COMMIT_SHORT_HASH@"
+    };
+}