#
# Copyright (C) 2018 by George Cave - gcave@stablecoder.ca
#
# Licensed 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.

set(
  USE_SANITIZER
  ""
  CACHE
    STRING
    "Compile with a sanitizer. Options are: Address, Memory, MemoryWithOrigins, Undefined, Thread, Leak, 'Address;Undefined'"
  )

function(append value)
  foreach(variable ${ARGN})
    set(${variable} "${${variable}} ${value}" PARENT_SCOPE)
  endforeach(variable)
endfunction()

if(USE_SANITIZER)
  append("-fno-omit-frame-pointer" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)

  if(UNIX)

    if(uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG")
      append("-O1" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
    endif()

    if(USE_SANITIZER MATCHES "([Aa]ddress);([Uu]ndefined)"
       OR USE_SANITIZER MATCHES "([Uu]ndefined);([Aa]ddress)")
      message(STATUS "Building with Address, Undefined sanitizers")
      append("-fsanitize=address,undefined" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
    elseif("${USE_SANITIZER}" MATCHES "([Aa]ddress)")
      # Optional: -fno-optimize-sibling-calls -fsanitize-address-use-after-scope
      message(STATUS "Building with Address sanitizer")
      append("-fsanitize=address" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
    elseif(USE_SANITIZER MATCHES "([Mm]emory([Ww]ith[Oo]rigins)?)")
      # Optional: -fno-optimize-sibling-calls -fsanitize-memory-track-origins=2
      append("-fsanitize=memory" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
      if(USE_SANITIZER MATCHES "([Mm]emory[Ww]ith[Oo]rigins)")
        message(STATUS "Building with MemoryWithOrigins sanitizer")
        append("-fsanitize-memory-track-origins" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
      else()
        message(STATUS "Building with Memory sanitizer")
      endif()
    elseif(USE_SANITIZER MATCHES "([Uu]ndefined)")
      message(STATUS "Building with Undefined sanitizer")
      append("-fsanitize=undefined" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
      if(EXISTS "${BLACKLIST_FILE}")
        append("-fsanitize-blacklist=${BLACKLIST_FILE}" CMAKE_C_FLAGS
               CMAKE_CXX_FLAGS)
      endif()
    elseif(USE_SANITIZER MATCHES "([Tt]hread)")
      message(STATUS "Building with Thread sanitizer")
      append("-fsanitize=thread" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
    elseif(USE_SANITIZER MATCHES "([Ll]eak)")
      message(STATUS "Building with Leak sanitizer")
      append("-fsanitize=leak" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
    else()
      message(
        FATAL_ERROR "Unsupported value of USE_SANITIZER: ${USE_SANITIZER}")
    endif()
  elseif(MSVC)
    if(USE_SANITIZER MATCHES "([Aa]ddress)")
      message(STATUS "Building with Address sanitizer")
      append("-fsanitize=address" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
    else()
      message(
        FATAL_ERROR
          "This sanitizer not yet supported in the MSVC environment: ${USE_SANITIZER}"
        )
    endif()
  else()
    message(FATAL_ERROR "USE_SANITIZER is not supported on this platform.")
  endif()

endif()