# SPDX-License-Identifier: Apache-2.0

if(NOT CMAKE_HOST_UNIX OR CMAKE_HOST_APPLE)
  message(FATAL_ERROR "The POSIX architecture only works on Linux. If on Windows or macOS "
          "consider using a virtual machine to run a Linux guest.")
endif()

# This native_simulator library is used to pass options to the
# native_simulator runner build. Currently the following are used:
#  INTERFACE_COMPILE_OPTIONS:
#      Extra compile options to be used during the build of the runner files
#      For ex. target_compile_options(native_simulator INTERFACE "-m64")
#  INTERFACE_LINK_OPTIONS:
#      Extra link options to be passed during the *final* link of the runner
#      with the embedded SW.
#      For ex. target_link_options(native_simulator INTERFACE "-lstdc++")
#  INTERFACE_SOURCES:
#      Extra sources to be built in the native simulator runner context
#      For ex. target_sources(native_simulator INTERFACE silly.c)
#      Note that these are built with the host libC and the include directories
#      the runner is built with.
#  RUNNER_LINK_LIBRARIES:
#      Extra libraries to link with the runner
#      For ex. set_property(TARGET native_simulator APPEND PROPERTY RUNNER_LINK_LIBRARIES "mylib.a")
#  LOCALIZE_EXTRA_OPTIONS:
#      Extra options to be passed to objcopy when localizing each Zephyr MCU image symbols
#      This can be used to hide symbols a library may have set as visible outside of
#      itself once the MCU image has been assembled.
#      For ex. set_property(TARGET native_simulator APPEND PROPERTY LOCALIZE_EXTRA_OPTIONS "--localize-symbol=spinel*")
#  Note: target_link_libraries() cannot be used on this library at this point.
#        target_link_libraries() updates INTERFACE_LINK_LIBRARIES but wrapping it with extra
#        information. This means we cannot directly pass it to the native_simulator runner build.
#        Check https://cmake.org/cmake/help/latest/prop_tgt/INTERFACE_LINK_LIBRARIES.html for more
#        info.
#        We use target_link_options() instead
add_library(native_simulator INTERFACE)
set_property(TARGET native_simulator PROPERTY RUNNER_LINK_LIBRARIES "")
set_property(TARGET native_simulator PROPERTY LOCALIZE_EXTRA_OPTIONS "")

set(NSI_DIR ${ZEPHYR_BASE}/scripts/native_simulator CACHE PATH "Path to the native simulator")

if(EXISTS ${CMAKE_CURRENT_LIST_DIR}/${CMAKE_HOST_SYSTEM_NAME}.${CMAKE_HOST_SYSTEM_PROCESSOR}.cmake)
  # @Intent: Set necessary compiler & linker options for this specific host architecture & OS
  include(${CMAKE_HOST_SYSTEM_NAME}.${CMAKE_HOST_SYSTEM_PROCESSOR}.cmake)
else() # Linux.x86_64
  if(CONFIG_64BIT)
    # some gcc versions fail to build without -fPIC
    zephyr_compile_options(-m64 -fPIC)
    zephyr_link_libraries(-m64)

    target_link_options(native_simulator INTERFACE "-m64")
    target_compile_options(native_simulator INTERFACE "-m64")
  else()
    zephyr_compile_options(-m32)
    zephyr_link_libraries(-m32)

    target_link_options(native_simulator INTERFACE "-m32")
    target_compile_options(native_simulator INTERFACE "-m32")

    # When building for 32bits x86, gcc defaults to using the old 8087 float arithmetic
    # which causes some issues with literal float comparisons. So we set it
    # to use the SSE2 float path instead
    # (clang defaults to use SSE, but, setting this option for it is safe)
    check_set_compiler_property(APPEND PROPERTY fpsse2 "SHELL:-msse2 -mfpmath=sse")
    zephyr_compile_options($<TARGET_PROPERTY:compiler,fpsse2>)
    target_compile_options(native_simulator INTERFACE "$<TARGET_PROPERTY:compiler,fpsse2>")
  endif()
endif()

zephyr_compile_options(
  ${ARCH_FLAG}
  )

zephyr_compile_options(
  -fvisibility=hidden
)

# While doing the partial linking of the native library, some symbols will be missing
# which are provided by the native simulator runner
zephyr_ld_options(
  -Wl,--unresolved-symbols=ignore-all
)

if(NOT CONFIG_EXTERNAL_LIBC)
  # Get the *compiler* include path, that is where the *compiler* provided headers are (not the
  # default libC ones). This includes basic headers like stdint.h, stddef.h or float.h
  # We expect something like
  #  /usr/lib/gcc/x86_64-linux-gnu/12/include or /usr/lib/llvm-14/lib/clang/14.0.0/include
  execute_process(
    COMMAND ${CMAKE_C_COMPILER} --print-file-name=include/stddef.h
    OUTPUT_VARIABLE _OUTPUT
    COMMAND_ERROR_IS_FATAL ANY
  )
  get_filename_component(COMPILER_OWN_INCLUDE_PATH "${_OUTPUT}" DIRECTORY)

  # Do not use the C library from this compiler/host,
  # but still use the basic compiler headers,
  # remove all operating system specific predefined macros,
  # no_builtin to avoid the compiler using builtin replacements for std library functions
  zephyr_compile_options(
    -nostdinc
    -isystem ${COMPILER_OWN_INCLUDE_PATH}
    "SHELL:-include ${ZEPHYR_BASE}/arch/posix/include/undef_system_defines.h"
    $<TARGET_PROPERTY:compiler,freestanding>
    $<TARGET_PROPERTY:compiler,no_builtin>
  )
endif()

if(CONFIG_COMPILER_WARNINGS_AS_ERRORS)
  target_compile_options(native_simulator INTERFACE $<TARGET_PROPERTY:compiler,warnings_as_errors>)
endif()

if(CONFIG_EXTERNAL_LIBC)
  # @Intent: Obtain compiler specific flags for no freestanding compilation
  zephyr_compile_options($<TARGET_PROPERTY:compiler,hosted>)
endif()

if(CONFIG_EXTERNAL_LIBCPP)
  target_link_options(native_simulator INTERFACE "-lstdc++")
endif()

zephyr_include_directories(${BOARD_DIR})

if(CONFIG_COVERAGE)
  target_compile_options(native_simulator INTERFACE $<TARGET_PROPERTY:compiler,coverage>)
  target_link_options(native_simulator INTERFACE $<TARGET_PROPERTY:linker,coverage>)
endif()

if(CONFIG_GPROF)
  zephyr_compile_options($<TARGET_PROPERTY:compiler,gprof>)
  zephyr_link_libraries($<TARGET_PROPERTY:linker,gprof>)

  target_link_options(native_simulator INTERFACE "-pg")
endif()

#
# Support for the LLVM Sanitizer toolchain instrumentation frameworks
# (supported by current gcc's as well)
#

if(CONFIG_ASAN)
  list(APPEND LLVM_SANITIZERS "address")
endif()

if(CONFIG_MSAN)
  list(APPEND LLVM_SANITIZERS "memory")
endif()

if(CONFIG_UBSAN)
  list(APPEND LLVM_SANITIZERS "undefined")
endif()

if(CONFIG_ASAN_RECOVER)
  zephyr_compile_options(-fsanitize-recover=all)
  target_compile_options(native_simulator INTERFACE "-fsanitize-recover=all")
endif()

if(CONFIG_ARCH_POSIX_LIBFUZZER)
  list(APPEND LLVM_SANITIZERS "fuzzer")
  target_compile_options(native_simulator INTERFACE "-DNSI_NO_MAIN=1")
  if(NOT CONFIG_64BIT)
    # On i386, libfuzzer seems to dynamically relocate the binary, so
    # we need to emit PIC code.  This limitation is undocumented and
    # poorly understood...
    zephyr_compile_options(-fPIC)
  endif()
endif()

list(JOIN LLVM_SANITIZERS "," LLVM_SANITIZERS_ARG)
if(NOT ${LLVM_SANITIZERS_ARG} STREQUAL "")
  set(LLVM_SANITIZERS_ARG "-fsanitize=${LLVM_SANITIZERS_ARG}")
  zephyr_compile_options("${LLVM_SANITIZERS_ARG}")

  target_link_options(native_simulator INTERFACE ${LLVM_SANITIZERS_ARG})
  target_compile_options(native_simulator INTERFACE ${LLVM_SANITIZERS_ARG})
endif()

include(natsim_optional.cmake)
add_subdirectory(core)
