gen_signature.cmake.in

# get these variables from CMakeLists.txt
set(SRC_DIR "@CMAKE_CURRENT_SOURCE_DIR@")
set(BIN_DIR "@CMAKE_CURRENT_BINARY_DIR@")
set(SEED_FILE "@SIGNATURE_SEED_FILE@")

# compute the signature from the seed file
file(SHA1 ${SEED_FILE} SHA1_SIGNATURE)

# use it to generate the file that will be compiled
message("sha1 for ${SEED_FILE} is ${SHA1_SIGNATURE}")
# potentially apply transformations like:
# string(SUBSTRING ${SHA1_SIGNATURE} 0 8 SHA1_SIGNATURE)
# message("short signature will be ${SHA1_SIGNATURE}")

# finally write a file that will be compiled with the signature in it
configure_file(
	${SRC_DIR}/signature.c.in
	${BIN_DIR}/signature.c
	@ONLY
	)