# - Convert ASN.1 file into C source and header files that can be used to create a wireshark dissector
#
# A2W_OUTPUT_DIR - directory where the generated packet-${PROTOCOL_NAME}.c is
# saved. The default location is meant for the Wireshark
# source tree. For external dissectors, set it to the
# absolute path (e.g. "${CMAKE_CURRENT_SOURCE_DIR}").

include(LocatePythonModule)
locate_python_module(asn2wrs REQUIRED PATHS "${CMAKE_SOURCE_DIR}/tools")

function(ASN2WRS)
if(NOT PROTO_OPT)
set(PROTO_OPT -p ${PROTOCOL_NAME})
elseif(PROTO_OPT STREQUAL "_EMPTY_")
set(PROTO_OPT)
endif()

if(NOT A2W_OUTPUT_DIR)
set(A2W_OUTPUT_DIR "${CMAKE_SOURCE_DIR}/epan/dissectors")
endif()

set(DISSECTOR "${A2W_OUTPUT_DIR}/packet-${PROTOCOL_NAME}.c")

# Besides the file dependency (for timestamp comparison), add a target such
# that other directories can request it to be built (ordering dependency).
foreach(_v EXTRA_CNF EXPORT_DEPENDS)
set(${_v}_targets)
foreach(entry IN LISTS ${_v})
string(REGEX MATCH "[^/]+-exp\\.cnf$" _exp_cnf_filename "${entry}")
if(_exp_cnf_filename)
list(APPEND ${_v}_targets generate-${_exp_cnf_filename})
endif()
endforeach()
endforeach()

# Creates a dissector in the source directory and store the timestamp.
add_custom_command(
OUTPUT packet-${PROTOCOL_NAME}-stamp
COMMAND "${PYTHON_EXECUTABLE}"
${PY_ASN2WRS}
${A2W_FLAGS}
${PROTO_OPT}
-c "${CMAKE_CURRENT_SOURCE_DIR}/${PROTOCOL_NAME}.cnf"
-s "${CMAKE_CURRENT_SOURCE_DIR}/packet-${PROTOCOL_NAME}-template"
-D "${CMAKE_CURRENT_SOURCE_DIR}"
-O "${A2W_OUTPUT_DIR}"
${EXT_ASN_FILE_LIST} ${ASN_FILE_LIST} ${EXT_ASN_FILE_LIST_LATE}
COMMAND
"${PYTHON_EXECUTABLE}" -c
"import shutil, sys; x,s,d=sys.argv; open(d, 'w'); shutil.copystat(s, d)"
"${A2W_OUTPUT_DIR}/packet-${PROTOCOL_NAME}.c"
packet-${PROTOCOL_NAME}-stamp
DEPENDS
"${PY_ASN2WRS}"
${SRC_FILES}
${EXTRA_CNF_targets}
${EXTRA_CNF}
VERBATIM
)

add_custom_target(generate_dissector-${PROTOCOL_NAME} ALL
DEPENDS packet-${PROTOCOL_NAME}-stamp
)

foreach(_asn2wrs_export_file IN LISTS EXPORT_FILES)
add_custom_command(
OUTPUT ${_asn2wrs_export_file}
COMMAND "${PYTHON_EXECUTABLE}"
"${PY_ASN2WRS}"
-E
${A2W_FLAGS}
${PROTO_OPT}
-c "${CMAKE_CURRENT_SOURCE_DIR}/${PROTOCOL_NAME}.cnf"
-D "${CMAKE_CURRENT_SOURCE_DIR}"
${EXT_ASN_FILE_LIST} ${ASN_FILE_LIST} ${EXT_ASN_FILE_LIST_LATE}
DEPENDS
"${PY_ASN2WRS}"
${SRC_FILES}
${EXPORT_DEPENDS_targets}
${EXPORT_DEPENDS}
)
# This target enables other dissectors to trigger the -exp cnf build
add_custom_target(generate-${_asn2wrs_export_file}
DEPENDS ${_asn2wrs_export_file}
)
endforeach()

endfunction()