# SPDX-License-Identifier: MIT
#
# Writes ${OUT} with the three strings src/build_info.hpp declares. Run both at
# configure time (so the file exists when add_executable names it) and on every
# build (so the commit and the timestamp are the ones that produced the binary).
#
# Expects: SRC (the source tree), OUT (the .cpp to write), VERSION.

set(COMMIT "unknown")
find_package(Git QUIET)
if(GIT_FOUND AND EXISTS "${SRC}/.git")
  execute_process(
    COMMAND ${GIT_EXECUTABLE} describe --always --dirty
    WORKING_DIRECTORY "${SRC}"
    OUTPUT_VARIABLE GIT_OUT
    OUTPUT_STRIP_TRAILING_WHITESPACE
    ERROR_QUIET
    RESULT_VARIABLE GIT_RC)
  if(GIT_RC EQUAL 0 AND NOT GIT_OUT STREQUAL "")
    set(COMMIT "${GIT_OUT}")
  endif()
endif()

string(TIMESTAMP STAMP "%Y-%m-%d %H:%M UTC" UTC)

file(WRITE "${OUT}"
"// SPDX-License-Identifier: MIT
// Generated by cmake/write_build_info.cmake. Do not edit, do not commit.
#include \"build_info.hpp\"

namespace udpscope::build_info {

const char* const kVersion = \"${VERSION}\";
const char* const kCommit = \"${COMMIT}\";
const char* const kTimestamp = \"${STAMP}\";

}  // namespace udpscope::build_info
")