# - Try to find libunwind
# Once done this will define
#
#  Unwind_FOUND - system has libunwind
#  unwind::unwind - cmake target for libunwind

include(FindPackageHandleStandardArgs)

find_path(Unwind_INCLUDE_DIR NAMES unwind.h libunwind.h DOC "unwind include directory")
find_library(Unwind_LIBRARY NAMES unwind DOC "unwind library")

mark_as_advanced(Unwind_INCLUDE_DIR Unwind_LIBRARY)

# Extract version information
if(Unwind_LIBRARY)
  set(_Unwind_VERSION_HEADER ${Unwind_INCLUDE_DIR}/libunwind-common.h)

  if(EXISTS ${_Unwind_VERSION_HEADER})
    file(READ ${_Unwind_VERSION_HEADER} _Unwind_VERSION_CONTENTS)

    string(REGEX REPLACE ".*#define UNW_VERSION_MAJOR[ \t]+([0-9]+).*" "\\1" Unwind_VERSION_MAJOR
                         "${_Unwind_VERSION_CONTENTS}")
    string(REGEX REPLACE ".*#define UNW_VERSION_MINOR[ \t]+([0-9]+).*" "\\1" Unwind_VERSION_MINOR
                         "${_Unwind_VERSION_CONTENTS}")
    string(REGEX REPLACE ".*#define UNW_VERSION_EXTRA[ \t]+([0-9]+).*" "\\1" Unwind_VERSION_PATCH
                         "${_Unwind_VERSION_CONTENTS}")

    set(Unwind_VERSION ${Unwind_VERSION_MAJOR}.${Unwind_VERSION_MINOR})

    if(CMAKE_MATCH_0)
      # Third version component may be empty
      set(Unwind_VERSION ${Unwind_VERSION}.${Unwind_VERSION_PATCH})
      set(Unwind_VERSION_COMPONENTS 3)
    else(CMAKE_MATCH_0)
      set(Unwind_VERSION_COMPONENTS 2)
    endif(CMAKE_MATCH_0)
  endif(EXISTS ${_Unwind_VERSION_HEADER})
endif(Unwind_LIBRARY)

# handle the QUIETLY and REQUIRED arguments and set Unwind_FOUND to TRUE
# if all listed variables are TRUE
find_package_handle_standard_args(Unwind REQUIRED_VARS Unwind_INCLUDE_DIR Unwind_LIBRARY
                                  VERSION_VAR Unwind_VERSION)

if(Unwind_FOUND)
  if(NOT TARGET unwind::unwind)
    add_library(unwind::unwind INTERFACE IMPORTED)

    set_property(TARGET unwind::unwind PROPERTY INTERFACE_INCLUDE_DIRECTORIES ${Unwind_INCLUDE_DIR})
    set_property(TARGET unwind::unwind PROPERTY INTERFACE_LINK_LIBRARIES ${Unwind_LIBRARY})
    set_property(TARGET unwind::unwind PROPERTY IMPORTED_CONFIGURATIONS RELEASE)
  endif(NOT TARGET unwind::unwind)
endif(Unwind_FOUND)