ref: 7a200942cedf07c18130957a4a27a889d88bc0e5
dir: /cmake/FindOpus.cmake/
# - Find opus
# Find the native opus includes and libraries
#
#  OPUS_INCLUDE_DIRS - where to find opus.h, etc.
#  OPUS_LIBRARIES    - List of libraries when using opus.
#  OPUS_FOUND        - True if Opus found.
if(OPUS_INCLUDE_DIR)
  # Already in cache, be silent
  set(OPUS_FIND_QUIETLY TRUE)
endif()
find_package(Ogg QUIET)
find_package(PkgConfig QUIET)
pkg_check_modules(PC_OPUS QUIET opus)
set(OPUS_VERSION ${PC_OPUS_VERSION})
find_path(OPUS_INCLUDE_DIR opus/opus.h
  HINTS
    ${PC_OPUS_INCLUDEDIR}
    ${PC_OPUS_INCLUDE_DIRS}
    ${OPUS_ROOT})
# MSVC built opus may be named opus_static.
# The provided project files name the library with the lib prefix.
find_library(OPUS_LIBRARY
  NAMES
    opus
    opus_static
    libopus
    libopus_static
  HINTS
    ${PC_OPUS_LIBDIR}
    ${PC_OPUS_LIBRARY_DIRS}
    ${OPUS_ROOT})
# Handle the QUIETLY and REQUIRED arguments and set OPUS_FOUND
# to TRUE if all listed variables are TRUE.
include(FindPackageHandleStandardArgs)
find_package_handle_standard_args(Opus
  REQUIRED_VARS
    OPUS_LIBRARY
    OPUS_INCLUDE_DIR
    Ogg_FOUND
  VERSION_VAR
    OPUS_VERSION)
if(OPUS_FOUND)
  set(OPUS_LIBRARIES ${OPUS_LIBRARY})
  set(OPUS_INCLUDE_DIRS ${OPUS_INCLUDE_DIR} ${Ogg_INCLUDE_DIRS})
  if(NOT TARGET Opus::opus)
    add_library(Opus::opus UNKNOWN IMPORTED)
    set_target_properties(Opus::opus PROPERTIES
      INTERFACE_INCLUDE_DIRECTORIES "${OPUS_INCLUDE_DIR}"
      IMPORTED_LOCATION "${OPUS_LIBRARY}"
      INTERFACE_LINK_LIBRARIES Ogg::ogg)
  endif()
endif()
mark_as_advanced(OPUS_INCLUDE_DIR OPUS_LIBRARY)