"Fancy" version statement (CMake part)

CMakeLists.txt

@@ -5,4 +5,52 @@ cmake_minimum_required(VERSION 3.2)
 
 project(linuxdeployqt)
 
+# read Git revision ID
+execute_process(
+    COMMAND git rev-parse --short HEAD
+    WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}
+    OUTPUT_VARIABLE GIT_COMMIT
+    OUTPUT_STRIP_TRAILING_WHITESPACE
+)
+
+# make sure Git revision ID and latest tag is not stored in the CMake cache
+# otherwise, one would have to reset the CMake cache on every new commit to make sure the Git commit ID is up to date
+unset(GIT_COMMIT CACHE)
+unset(GIT_LATEST_TAG CACHE)
+
+# read Git revision ID and latest tag number
+execute_process(
+    COMMAND git rev-parse --short HEAD
+    WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}
+    OUTPUT_VARIABLE GIT_COMMIT
+    OUTPUT_STRIP_TRAILING_WHITESPACE
+)
+execute_process(
+    COMMAND git rev-list --tags --skip=1 --max-count=1
+    WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}
+    OUTPUT_VARIABLE GIT_TAG_ID
+    OUTPUT_STRIP_TRAILING_WHITESPACE
+)
+execute_process(
+    COMMAND git describe --tags ${GIT_TAG_ID} --abbrev=0
+    WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}
+    OUTPUT_VARIABLE GIT_TAG_NAME
+    OUTPUT_STRIP_TRAILING_WHITESPACE
+)
+
+# set version and build number
+set(VERSION 1-alpha)
+if("$ENV{TRAVIS_BUILD_NUMBER}" STREQUAL "")
+    set(BUILD_NUMBER "<local dev build>")
+else()
+    set(BUILD_NUMBER "$ENV{TRAVIS_BUILD_NUMBER}")
+endif()
+
+# get current date
+execute_process(
+    COMMAND env LC_ALL=C date -u "+%Y-%m-%d %H:%M:%S %Z"
+    OUTPUT_VARIABLE DATE
+    OUTPUT_STRIP_TRAILING_WHITESPACE
+)
+
 add_subdirectory(tools/linuxdeployqt)

tools/linuxdeployqt/CMakeLists.txt

@@ -1,5 +1,11 @@
 set(CMAKE_AUTOMOC ON)
 
+# expose version data as compiler definition
+add_definitions("-DLINUXDEPLOYQT_VERSION=\"${GIT_TAG_NAME}\"")
+add_definitions("-DLINUXDEPLOYQT_GIT_COMMIT=\"${GIT_COMMIT}\"")
+add_definitions("-DBUILD_DATE=\"${DATE}\"")
+add_definitions("-DBUILD_NUMBER=\"${BUILD_NUMBER}\"")
+
 find_package(Qt5 REQUIRED COMPONENTS Core)
 
 add_executable(linuxdeployqt main.cpp shared.cpp)