#

#  Copyright (c) 2018 Anderson Toshiyuki Sasaki <ansasaki@redhat.com>

#

#  Redistribution and use is allowed according to the terms of the New

#  BSD license.

#  For details see the accompanying COPYING-CMAKE-SCRIPTS file.

#

#.rst:

# ExtractSymbols

# --------------

#

# This is a helper script for FindABImap.cmake.

#

# Extract symbols from header files and output a list to a file.

# This script is run in build time to extract symbols from the provided header

# files. This way, symbols added or removed can be checked and used to update

# the symbol version script.

#

# All symbols followed by the character ``'('`` are extracted. If a

# ``FILTER_PATTERN`` is provided, only the lines containing the given string are

# considered.

#

# Expected defined variables

# --------------------------

#

# ``HEADERS_LIST_FILE``:

#   Required, expects a file containing the list of header files to be parsed.

#

# ``OUTPUT_PATH``:

#   Required, expects the output file path.

#

# Optionally defined variables

# ----------------------------

#

# ``FILTER_PATTERN``:

#   Expects a string. Only lines containing the given string will be considered

#   when extracting symbols.

#

if (NOT DEFINED OUTPUT_PATH)

    message(SEND_ERROR "OUTPUT_PATH not defined")

endif()

if (NOT DEFINED HEADERS_LIST_FILE)

    message(SEND_ERROR "HEADERS not defined")

endif()

file(READ ${HEADERS_LIST_FILE} HEADERS_LIST)

set(symbols)

foreach(header ${HEADERS_LIST})

    # Filter only lines containing the FILTER_PATTERN

    file(STRINGS ${header} contain_filter

      REGEX "^.*${FILTER_PATTERN}.*[(]"

    )

    # Remove function-like macros

    foreach(line ${contain_filter})

        if (NOT ${line} MATCHES ".*#[ ]*define")

            list(APPEND not_macro ${line})

        endif()

    endforeach()

    set(functions)

    # Get only the function names followed by '('

    foreach(line ${not_macro})

        string(REGEX MATCHALL "[a-zA-Z0-9_]+[ ]*[(]" func ${line})

        list(APPEND functions ${func})

    endforeach()

    set(extracted_symbols)

    # Remove '('

    foreach(line ${functions})

        string(REGEX REPLACE "[(]" "" symbol ${line})

        string(STRIP "${symbol}" symbol)

        list(APPEND extracted_symbols ${symbol})

    endforeach()

    list(APPEND symbols ${extracted_symbols})

endforeach()

list(REMOVE_DUPLICATES symbols)

list(SORT symbols)

string(REPLACE ";" "\n" symbols_list "${symbols}")

file(WRITE ${OUTPUT_PATH} "${symbols_list}")