Merge pull request #24 from flightaware/BCK-5541

Embed git hash/branch info in cpptcl libs

Author: maryryang2

CMakeLists.txt

@@ -2,6 +2,9 @@ cmake_minimum_required(VERSION 3.8)
 
 project(cpptcl)
 
+include(cmake/version.cmake)
+load_git_properties(cpptcl ${CMAKE_BINARY_DIR}/generated)
+
 set(CPPTCL_VERSION 2.2.5)
 
 if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
@@ -61,8 +64,10 @@ add_compile_options(${OPTS})
 set(cpptcl_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR})
 
 list(APPEND SRCS ${cpptcl_SOURCE_DIR}/cpptcl.cc)
+list(APPEND SRCS ${CMAKE_BINARY_DIR}/generated/cpptcl_version.cpp)
 list(APPEND HDRS ${cpptcl_SOURCE_DIR}/cpptcl/cpptcl.h)
 list(APPEND HDRS ${cpptcl_SOURCE_DIR}/cpptcl/cpptcl_object.h)
+list(APPEND HDRS ${cpptcl_SOURCE_DIR}/cpptcl/version.h)
 list(APPEND HDRS_DETAILS ${cpptcl_SOURCE_DIR}/cpptcl/details/callbacks.h)
 list(APPEND HDRS_DETAILS ${cpptcl_SOURCE_DIR}/cpptcl/details/callbacks_v.h) 
 list(APPEND HDRS_DETAILS ${cpptcl_SOURCE_DIR}/cpptcl/details/constructors.h)
@@ -85,7 +90,7 @@ target_include_directories(cpptcl
 		$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>
 	)
 target_include_directories(cpptcl PUBLIC ${TCL_INCLUDE_PATH})
-target_link_libraries(cpptcl ${TCL_STUB_LIBRARY})
+target_link_libraries(cpptcl PUBLIC ${TCL_STUB_LIBRARY})
 
 add_library(cpptcl_static STATIC ${SRCS} ${HDRS} ${HDRS_DETAILS})
 add_library(cpptcl::cpptcl_static ALIAS cpptcl_static)
@@ -114,7 +119,7 @@ target_include_directories(cpptcl_runtime
 		$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>
 	)
 target_include_directories(cpptcl_runtime PUBLIC ${TCL_INCLUDE_PATH})
-target_link_libraries(cpptcl_runtime ${TCL_LIBRARY})
+target_link_libraries(cpptcl_runtime PUBLIC ${TCL_LIBRARY})
 
 if (CPPTCL_TEST)
 	add_subdirectory(test)

cmake/version.cmake

@@ -0,0 +1,51 @@
+function (load_git_properties prefix output_dir)
+
+    # Load the current working branch
+    execute_process(
+        COMMAND git symbolic-ref -q --short HEAD
+        WORKING_DIRECTORY ${CMAKE_CURRENT_LIST_DIR}
+        OUTPUT_VARIABLE GIT_BRANCH
+        OUTPUT_STRIP_TRAILING_WHITESPACE
+    )
+
+    if (GIT_BRANCH STREQUAL "")
+        execute_process(
+            COMMAND git describe --tags --exact-match
+            WORKING_DIRECTORY ${CMAKE_CURRENT_LIST_DIR}
+            OUTPUT_VARIABLE GIT_BRANCH
+            OUTPUT_STRIP_TRAILING_WHITESPACE
+        )
+    endif ()
+
+    # Get the latest abbreviated commit hash of the working branch
+    execute_process(
+        COMMAND git log -1 --format=%h
+        WORKING_DIRECTORY ${CMAKE_CURRENT_LIST_DIR}
+        OUTPUT_VARIABLE GIT_HASH
+        OUTPUT_STRIP_TRAILING_WHITESPACE
+    )
+
+    if ("${GIT_BRANCH}" STREQUAL "")
+        set(GIT_BRANCH "N/A")
+    endif ()
+
+    if ("${GIT_HASH}" STREQUAL "")
+        set(GIT_HASH "N/A")
+    endif ()
+
+    string(TOUPPER "${prefix}" var_prefix)
+    string(CONCAT VERSION_DATA "const char* ${var_prefix}_GIT_HASH = \"${GIT_HASH}\";\n"
+        "const char* ${var_prefix}_GIT_BRANCH = \"${GIT_BRANCH}\";\n"
+        )
+
+    if (EXISTS ${output_dir}/${prefix}_version.cpp)
+        file(READ ${output_dir}/${prefix}_version.cpp VERSION_DATA_)
+    else ()
+        set(VERSION_DATA_ "")
+    endif ()
+
+    if (NOT "${VERSION_DATA}" STREQUAL "${VERSION_DATA_}")
+        file(WRITE ${output_dir}/${prefix}_version.cpp "${VERSION_DATA}")
+    endif ()
+
+endfunction ()

cpptcl/version.h

@@ -0,0 +1,19 @@
+#ifndef CPPTCL_VERSION_H
+#define CPPTCL_VERSION_H
+
+// Variables are autogenerated and compiled
+// into the library by cmake
+extern "C" {
+    extern const char* CPPTCL_GIT_HASH;
+    extern const char* CPPTCL_GIT_BRANCH;
+}
+
+const char* cpptcl_git_hash() {
+    return CPPTCL_GIT_HASH;
+}
+
+const char* cpptcl_git_branch() {
+    return CPPTCL_GIT_BRANCH;
+}
+
+#endif //CPPTCL_VERSION_H