cmake/nuttx_add_symtab.cmake

# ##############################################################################
# cmake/nuttx_add_symtab.cmake
#
# SPDX-License-Identifier: Apache-2.0
#
# Licensed to the Apache Software Foundation (ASF) under one or more contributor
# license agreements.  See the NOTICE file distributed with this work for
# additional information regarding copyright ownership.  The ASF licenses this
# file to you under the Apache License, Version 2.0 (the "License"); you may not
# use this file except in compliance with the License.  You may obtain a copy of
# the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
# License for the specific language governing permissions and limitations under
# the License.
#
# ##############################################################################

# ~~~
# nuttx_add_symtab
#
# Description:
#   Generates a symbol table of undefined symbols from a set of binaries
#
# Parameters:
#   NAME    : name of symtab (output will be symtab_${NAME}.c)
#   BINARIES: list of binary target names to process (dependencies will be added
#             to these targets)
#   PREFIX  : optional prefix to add to symtab variable name
#   EXCLUDE : optional list of symbols to exclude (ie: assume they are defined)
# ~~~

function(nuttx_add_symtab)
  nuttx_parse_function_args(
    FUNC
    nuttx_add_symtab
    ONE_VALUE
    NAME
    PREFIX
    OPTIONS
    HEADER
    MULTI_VALUE
    EXCLUDE
    BINARIES
    REQUIRED
    NAME
    BINARIES
    ARGN
    ${ARGN})

  # get path to binaries
  set(BINARY_PATHS)
  foreach(binary ${BINARIES})
    # this way of getting the path will select the actual ELF binary, even when
    # this was built by means of an intermediate library on non-ELF platforms
    list(APPEND BINARY_PATHS $<TARGET_PROPERTY:${binary},ELF_BINARY>)
  endforeach()

  if(EXCLUDE)
    string(REPLACE ";" " " EXCLUDE_STRING ${EXCLUDE})
  endif()

  # generate list of undefined symbols
  add_custom_command(
    OUTPUT symtab_${NAME}.dat
    COMMAND ${CMAKE_NM} ${BINARY_PATHS} | fgrep ' U ' | sed -e "s/^[ ]*//g" |
            cut -d' ' -f2 | sort | uniq > symtab_${NAME}.dat
    COMMAND
      if [ \"${EXCLUDE}\" != \"\" ]\; then fgrep -v -x ${EXCLUDE_STRING}
      symtab_${NAME}.dat > symtab_${NAME}.dat2\; mv symtab_${NAME}.dat2
      symtab_${NAME}.dat\; fi
    DEPENDS ${BINARIES})

  add_custom_target(symtab_${NAME}_dat DEPENDS symtab_${NAME}.dat)

  # generate declarations for symbols and symtab entries as headers
  add_custom_command(
    OUTPUT symtab_${NAME}_declarations.h symtab_${NAME}_entries.h
    COMMAND sed -E 's|\(.+\)|extern void *\\1\;|g' symtab_${NAME}.dat >
            symtab_${NAME}_declarations.h
    COMMAND sed -E 's|\(.+\)|{ \"\\1\", \\&\\1 },|g' symtab_${NAME}.dat >
            symtab_${NAME}_entries.h
    DEPENDS symtab_${NAME}_dat)

  # generate code which instantiates the symbol table
  configure_file(${CMAKE_SOURCE_DIR}/cmake/symtab.c.in symtab_${NAME}.c @ONLY)

  # define an internal library to build the symtab file on its own
  add_library(symtab_${NAME} OBJECT
              ${CMAKE_CURRENT_BINARY_DIR}/symtab_${NAME}.c)

  # Make the dependance between .c and .h explicit. This is necessary since
  # using configure_file() does not seem to allow this to be automatically
  # guessed by CMake
  set_property(
    SOURCE ${CMAKE_CURRENT_BINARY_DIR}/symtab_${NAME}.c
    APPEND
    PROPERTY OBJECT_DEPENDS
             ${CMAKE_CURRENT_BINARY_DIR}/symtab_${NAME}_declarations.h
             ${CMAKE_CURRENT_BINARY_DIR}/symtab_${NAME}_entries.h)

  nuttx_add_library_internal(symtab_${NAME})

  if(PREFIX)
    target_compile_definitions(symtab_${NAME} PRIVATE -DSYMTAB_PREFIX=${PREFIX})
  endif()
endfunction()