# Generate the config.h to compile with specific intrinsics / libs.

## Check for compiler options.

include(CheckCSourceCompiles)

check_c_source_compiles("

    int main(void) {

      (void)__builtin_bswap16(0);

      return 0;

    }

  "

  HAVE_BUILTIN_BSWAP16

)

check_c_source_compiles("

    int main(void) {

      (void)__builtin_bswap32(0);

      return 0;

    }

  "

  HAVE_BUILTIN_BSWAP32

)

check_c_source_compiles("

    int main(void) {

      (void)__builtin_bswap64(0);

      return 0;

    }

  "

  HAVE_BUILTIN_BSWAP64

)

## Check for libraries.

find_package(Threads)

if(Threads_FOUND)

  if(CMAKE_USE_PTHREADS_INIT)

    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -pthread")

  endif()

  foreach(PTHREAD_TEST HAVE_PTHREAD_PRIO_INHERIT PTHREAD_CREATE_UNDETACHED)

    check_c_source_compiles("

        #include <pthread.h>

        int main (void) {

          int attr = ${PTHREAD_TEST};

          return attr;

        }

      " ${PTHREAD_TEST}

    )

  endforeach()

  list(APPEND WEBP_DEP_LIBRARIES ${CMAKE_THREAD_LIBS_INIT})

endif()

set(WEBP_USE_THREAD ${Threads_FOUND})

# TODO: this seems unused, check with autotools.

set(LT_OBJDIR ".libs/")

# Only useful for vwebp, so useless for now.

# find_package(OpenGL)

# set(WEBP_HAVE_GL ${OPENGL_FOUND})

# set(WEBP_DEP_INCLUDE_DIRS ${WEBP_DEP_INCLUDE_DIRS} ${OPENGL_INCLUDE_DIRS})

# set(WEBP_DEP_LIBRARIES ${WEBP_DEP_LIBRARIES} ${OPENGL_LIBRARIES})

# Find the standard C math library.

find_library(MATH_LIBRARY NAMES m)

if(MATH_LIBRARY)

  list(APPEND WEBP_DEP_LIBRARIES ${MATH_LIBRARY})

endif()

# Find the standard image libraries.

set(WEBP_DEP_IMG_LIBRARIES)

set(WEBP_DEP_IMG_INCLUDE_DIRS)

foreach(I_LIB PNG JPEG TIFF)

  find_package(${I_LIB})

  set(WEBP_HAVE_${I_LIB} ${${I_LIB}_FOUND})

  if(${I_LIB}_FOUND)

    list(APPEND WEBP_DEP_IMG_LIBRARIES ${${I_LIB}_LIBRARIES})

    list(APPEND WEBP_DEP_IMG_INCLUDE_DIRS

         ${${I_LIB}_INCLUDE_DIR} ${${I_LIB}_INCLUDE_DIRS})

  endif()

endforeach()

if(WEBP_DEP_IMG_INCLUDE_DIRS)

  list(REMOVE_DUPLICATES WEBP_DEP_IMG_INCLUDE_DIRS)

endif()

# GIF detection, gifdec isn't part of the imageio lib.

include(CMakePushCheckState)

set(WEBP_DEP_GIF_LIBRARIES)

set(WEBP_DEP_GIF_INCLUDE_DIRS)

find_package(GIF)

set(WEBP_HAVE_GIF ${GIF_FOUND})

if(GIF_FOUND)

  # GIF find_package only locates the header and library, it doesn't fail

  # compile tests when detecting the version, but falls back to 3 (as of at

  # least cmake 3.7.2). Make sure the library links to avoid incorrect

  # detection when cross compiling.

  cmake_push_check_state()

  set(CMAKE_REQUIRED_LIBRARIES ${GIF_LIBRARIES})

  set(CMAKE_REQUIRED_INCLUDES ${GIF_INCLUDE_DIR})

  check_c_source_compiles("

      #include <gif_lib.h>

      int main(void) {

        (void)DGifOpenFileHandle;

        return 0;

      }

      " GIF_COMPILES

  )

  cmake_pop_check_state()

  if(GIF_COMPILES)

    list(APPEND WEBP_DEP_GIF_LIBRARIES ${GIF_LIBRARIES})

    list(APPEND WEBP_DEP_GIF_INCLUDE_DIRS ${GIF_INCLUDE_DIR})

  else()

    unset(GIF_FOUND)

  endif()

endif()

## Check for specific headers.

include(CheckIncludeFiles)

check_include_files("stdlib.h;stdarg.h;string.h;float.h" STDC_HEADERS)

check_include_files(dlfcn.h HAVE_DLFCN_H)

check_include_files(GLUT/glut.h HAVE_GLUT_GLUT_H)

check_include_files(GL/glut.h HAVE_GL_GLUT_H)

check_include_files(inttypes.h HAVE_INTTYPES_H)

check_include_files(memory.h HAVE_MEMORY_H)

check_include_files(OpenGL/glut.h HAVE_OPENGL_GLUT_H)

check_include_files(shlwapi.h HAVE_SHLWAPI_H)

check_include_files(stdint.h HAVE_STDINT_H)

check_include_files(stdlib.h HAVE_STDLIB_H)

check_include_files(strings.h HAVE_STRINGS_H)

check_include_files(string.h HAVE_STRING_H)

check_include_files(sys/stat.h HAVE_SYS_STAT_H)

check_include_files(sys/types.h HAVE_SYS_TYPES_H)

check_include_files(unistd.h HAVE_UNISTD_H)

check_include_files(wincodec.h HAVE_WINCODEC_H)

check_include_files(windows.h HAVE_WINDOWS_H)

# Windows specifics

if(HAVE_WINCODEC_H)

  list(APPEND WEBP_DEP_LIBRARIES shlwapi ole32 windowscodecs)

endif()

## Check for SIMD extensions.

include(${CMAKE_CURRENT_LIST_DIR}/cpu.cmake)

## Define extra info.

set(PACKAGE ${PROJECT_NAME})

set(PACKAGE_NAME ${PROJECT_NAME})

# Read from configure.ac.

file(READ ${CMAKE_CURRENT_SOURCE_DIR}/configure.ac CONFIGURE_AC)

string(REGEX MATCHALL "\\[([0-9a-z\\.:/]*)\\]"

  CONFIGURE_AC_PACKAGE_INFO ${CONFIGURE_AC}

)

function(strip_bracket VAR)

  string(LENGTH ${${VAR}} TMP_LEN)

  math(EXPR TMP_LEN ${TMP_LEN}-2)

  string(SUBSTRING ${${VAR}} 1 ${TMP_LEN} TMP_SUB)

  set(${VAR} ${TMP_SUB} PARENT_SCOPE)

endfunction()

list(GET CONFIGURE_AC_PACKAGE_INFO 1 PACKAGE_VERSION)

strip_bracket(PACKAGE_VERSION)

list(GET CONFIGURE_AC_PACKAGE_INFO 2 PACKAGE_BUGREPORT)

strip_bracket(PACKAGE_BUGREPORT)

list(GET CONFIGURE_AC_PACKAGE_INFO 3 PACKAGE_URL)

strip_bracket(PACKAGE_URL)

# Build more info.

set(PACKAGE_STRING "${PACKAGE_NAME} ${PACKAGE_VERSION}")

set(PACKAGE_TARNAME ${PACKAGE_NAME})

set(VERSION ${PACKAGE_VERSION})