# CMakeLists.txt

# Copyright (C) 2007-2015 Glenn Randers-Pehrson

# This code is released under the libpng license.

# For conditions of distribution and use, see the disclaimer

# and license in png.h

cmake_minimum_required(VERSION 2.4.4)

set(CMAKE_ALLOW_LOOSE_LOOP_CONSTRUCTS true)

set(CMAKE_CONFIGURATION_TYPES "Release;Debug;MinSizeRel;RelWithDebInfo")

project(libpng C)

enable_testing()

set(PNGLIB_MAJOR 1)

set(PNGLIB_MINOR 6)

set(PNGLIB_RELEASE 21)

set(PNGLIB_NAME libpng${PNGLIB_MAJOR}${PNGLIB_MINOR})

set(PNGLIB_VERSION ${PNGLIB_MAJOR}.${PNGLIB_MINOR}.${PNGLIB_RELEASE})

# needed packages

find_package(ZLIB REQUIRED)

include_directories(${ZLIB_INCLUDE_DIR})

if(NOT WIN32)

  find_library(M_LIBRARY

    NAMES m

    PATHS /usr/lib /usr/local/lib

  )

  if(NOT M_LIBRARY)

    message(STATUS "math lib 'libm' not found; floating point support disabled")

  endif()

else()

  # not needed on windows

  set(M_LIBRARY "")

endif()

# COMMAND LINE OPTIONS

option(PNG_SHARED "Build shared lib" ON)

option(PNG_STATIC "Build static lib" ON)

option(PNG_TESTS  "Build libpng tests" ON)

# Many more configuration options could be added here

option(PNG_FRAMEWORK "Build OS X framework" OFF)

option(PNG_DEBUG     "Build with debug output" OFF)

option(PNGARG        "Disable ANSI-C prototypes" OFF)

# SET LIBNAME

set(PNG_LIB_NAME png${PNGLIB_MAJOR}${PNGLIB_MINOR})

# to distinguish between debug and release lib

set(CMAKE_DEBUG_POSTFIX "d")

# Use the prebuilt pnglibconf.h file from the scripts folder

# TODO: fix this by building with awk; without this no cmake build can be

# configured directly (to do so indirectly use your local awk to build a

# pnglibconf.h in the build directory.)

configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.h.prebuilt

               ${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h)

include_directories(${CMAKE_CURRENT_BINARY_DIR})

# OUR SOURCES

set(libpng_public_hdrs

  png.h

  pngconf.h

  ${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h

)

set(libpng_sources

  ${libpng_public_hdrs}

  pngdebug.h

  pnginfo.h

  pngpriv.h

  pngstruct.h

  png.c

  pngerror.c

  pngget.c

  pngmem.c

  pngpread.c

  pngread.c

  pngrio.c

  pngrtran.c

  pngrutil.c

  pngset.c

  pngtrans.c

  pngwio.c

  pngwrite.c

  pngwtran.c

  pngwutil.c

)

set(pngtest_sources

  pngtest.c

)

set(pngvalid_sources

  contrib/libtests/pngvalid.c

)

set(pngstest_sources

  contrib/libtests/pngstest.c

)

# SOME NEEDED DEFINITIONS

if(MSVC)

  add_definitions(-D_CRT_SECURE_NO_DEPRECATE)

endif(MSVC)

if(PNG_DEBUG)

  add_definitions(-DPNG_DEBUG)

endif()

# NOW BUILD OUR TARGET

include_directories(${CMAKE_CURRENT_SOURCE_DIR} ${ZLIB_INCLUDE_DIR})

unset(PNG_LIB_TARGETS)

if(PNG_SHARED)

  add_library(${PNG_LIB_NAME} SHARED ${libpng_sources})

  set(PNG_LIB_TARGETS ${PNG_LIB_NAME})

  if(MSVC)

    # msvc does not append 'lib' - do it here to have consistent name

    set_target_properties(${PNG_LIB_NAME} PROPERTIES PREFIX "lib")

    set_target_properties(${PNG_LIB_NAME} PROPERTIES IMPORT_PREFIX "lib")

  endif()

  target_link_libraries(${PNG_LIB_NAME} ${ZLIB_LIBRARY} ${M_LIBRARY})

endif()

if(PNG_STATIC)

  # does not work without changing name

  set(PNG_LIB_NAME_STATIC ${PNG_LIB_NAME}_static)

  add_library(${PNG_LIB_NAME_STATIC} STATIC ${libpng_sources})

  list(APPEND PNG_LIB_TARGETS ${PNG_LIB_NAME_STATIC})

  if(MSVC)

    # msvc does not append 'lib' - do it here to have consistent name

    set_target_properties(${PNG_LIB_NAME_STATIC} PROPERTIES PREFIX "lib")

  endif()

  target_link_libraries(${PNG_LIB_NAME_STATIC} ${ZLIB_LIBRARY} ${M_LIBRARY})

endif()

if(PNG_FRAMEWORK)

  set(PNG_LIB_NAME_FRAMEWORK ${PNG_LIB_NAME}_framework)

  add_library(${PNG_LIB_NAME_FRAMEWORK} SHARED ${libpng_sources})

  list(APPEND PNG_LIB_TARGETS ${PNG_LIB_NAME_FRAMEWORK})

  set_target_properties(${PNG_LIB_NAME_FRAMEWORK} PROPERTIES

    FRAMEWORK TRUE

    FRAMEWORK_VERSION ${PNGLIB_VERSION}

    MACOSX_FRAMEWORK_SHORT_VERSION_STRING ${PNGLIB_MAJOR}.${PNGLIB_MINOR}

    MACOSX_FRAMEWORK_BUNDLE_VERSION ${PNGLIB_VERSION}

    MACOSX_FRAMEWORK_IDENTIFIER org.libpng.libpng

    XCODE_ATTRIBUTE_INSTALL_PATH "@rpath"

    PUBLIC_HEADER "${libpng_public_hdrs}"

    OUTPUT_NAME png)

  target_link_libraries(${PNG_LIB_NAME_FRAMEWORK} ${ZLIB_LIBRARY} ${M_LIBRARY})

endif()

if(NOT PNG_LIB_TARGETS)

  message(SEND_ERROR

    "No library variant selected to build. "

    "Please enable at least one of the following options: "

    " PNG_STATIC, PNG_SHARED, PNG_FRAMEWORK")

endif()

if(PNG_SHARED AND WIN32)

  set_target_properties(${PNG_LIB_NAME} PROPERTIES DEFINE_SYMBOL PNG_BUILD_DLL)

endif()

if(PNG_TESTS AND PNG_SHARED)

  # does not work with msvc due to png_lib_ver issue

  add_executable(pngtest ${pngtest_sources})

  target_link_libraries(pngtest ${PNG_LIB_NAME})

  add_test(pngtest ./pngtest ${CMAKE_CURRENT_SOURCE_DIR}/pngtest.png)

  #

  add_executable(pngvalid ${pngvalid_sources})

  target_link_libraries(pngvalid ${PNG_LIB_NAME})

  add_test(pngvalid ./pngvalid)

  add_executable(pngstest ${pngstest_sources})

  target_link_libraries(pngstest ${PNG_LIB_NAME})

  add_test(pngstest ./pngstest

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g01.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g02.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g04.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g08.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g16.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn2c08.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn2c16.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn3p01.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn3p02.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn3p04.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn3p08.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn4a08.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn4a16.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn6a08.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn6a16.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn0g01.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn0g02.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn0g04.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn2c16.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn3p08.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbgn2c16.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbgn3p08.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbrn2c08.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbwn0g16.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbwn3p08.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbyn3p08.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftp0n0g08.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftp0n2c08.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftp0n3p08.png

    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftp1n3p08.png

  )

endif()

# Ensure the CMAKE_LIBRARY_OUTPUT_DIRECTORY is set

IF(NOT CMAKE_LIBRARY_OUTPUT_DIRECTORY)

  SET(CMAKE_LIBRARY_OUTPUT_DIRECTORY "lib")

ENDIF(NOT CMAKE_LIBRARY_OUTPUT_DIRECTORY)

# Set a variable with CMake code which:

# Creates a symlink from src to dest (if possible) or alternatively

# copies if different.

macro(CREATE_SYMLINK SRC_FILE DEST_FILE)

  FILE(REMOVE ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE})

  if(WIN32 AND NOT CYGWIN AND NOT MSYS)

    ADD_CUSTOM_COMMAND(

        OUTPUT ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE}   ${CMAKE_CURRENT_BINARY_DIR}/${DEST_FILE}

        COMMAND ${CMAKE_COMMAND} -E copy_if_different  "${SRC_FILE}" ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE}

        COMMAND ${CMAKE_COMMAND} -E copy_if_different  "${SRC_FILE}" ${CMAKE_CURRENT_BINARY_DIR}/${DEST_FILE}

        DEPENDS ${PNG_LIB_TARGETS}

        )

    ADD_CUSTOM_TARGET(${DEST_FILE}_COPY ALL DEPENDS ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE})

  else(WIN32 AND NOT CYGWIN AND NOT MSYS)

    get_filename_component(LINK_TARGET "${SRC_FILE}" NAME)

    execute_process(COMMAND ${CMAKE_COMMAND} -E make_directory ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_LIBRARY_OUTPUT_DIRECTORY})

    execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink "${LINK_TARGET}" ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE} WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})

    execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink "${LINK_TARGET}" ${DEST_FILE} WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})

  endif(WIN32 AND NOT CYGWIN AND NOT MSYS)

endmacro()

# libpng is a library so default to 'lib'

if(NOT DEFINED CMAKE_INSTALL_LIBDIR)

  set(CMAKE_INSTALL_LIBDIR lib)

endif(NOT DEFINED CMAKE_INSTALL_LIBDIR)

# CREATE PKGCONFIG FILES

# we use the same files like ./configure, so we have to set its vars

# Only do this on Windows for Cygwin - the files don't make much sense outside

# a UNIX look alike

if(NOT WIN32 OR CYGWIN OR MINGW)

  set(prefix      ${CMAKE_INSTALL_PREFIX})

  set(exec_prefix ${CMAKE_INSTALL_PREFIX})

  set(libdir      ${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_LIBDIR})

  set(includedir  ${CMAKE_INSTALL_PREFIX}/include)

  set(LIBS        "-lz -lm")

  configure_file(${CMAKE_CURRENT_SOURCE_DIR}/libpng.pc.in

    ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}.pc @ONLY)

  CREATE_SYMLINK(${PNGLIB_NAME}.pc libpng.pc)

  configure_file(${CMAKE_CURRENT_SOURCE_DIR}/libpng-config.in

    ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config @ONLY)

  CREATE_SYMLINK(${PNGLIB_NAME}-config libpng-config)

endif(NOT WIN32 OR CYGWIN OR MINGW)

# SET UP LINKS

if(PNG_SHARED)

  set_target_properties(${PNG_LIB_NAME} PROPERTIES

#   VERSION 16.${PNGLIB_RELEASE}.1.6.21

    VERSION 16.${PNGLIB_RELEASE}.0

    SOVERSION 16

    CLEAN_DIRECT_OUTPUT 1)

endif()

if(PNG_STATIC)

  # MSVC doesn't use a different file extension for shared vs. static

  # libs.  We are able to change OUTPUT_NAME to remove the _static

  # for all other platforms.

  if(NOT MSVC)

    set_target_properties(${PNG_LIB_NAME_STATIC} PROPERTIES

      OUTPUT_NAME ${PNG_LIB_NAME}

      CLEAN_DIRECT_OUTPUT 1)

  endif()

endif()

# If CMake > 2.4.x, we set a variable used below to export

# targets to an export file.

# TODO: Use VERSION_GREATER after our cmake_minimum_required >= 2.6.2

if(CMAKE_MAJOR_VERSION GREATER 1 AND CMAKE_MINOR_VERSION GREATER 4)

  set(PNG_EXPORT_RULE EXPORT libpng)

elseif(CMAKE_MAJOR_VERSION GREATER 2) # future proof

  set(PNG_EXPORT_RULE EXPORT libpng)

endif()

# INSTALL

if(NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL )

  install(TARGETS ${PNG_LIB_TARGETS}

      ${PNG_EXPORT_RULE}

      RUNTIME DESTINATION bin

      LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}

      ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}

      FRAMEWORK DESTINATION ${CMAKE_INSTALL_LIBDIR})

  if(PNG_SHARED)

    # Create a symlink for libpng.dll.a => libpng16.dll.a on Cygwin

    if(CYGWIN OR MINGW)

       get_target_property(BUILD_TARGET_LOCATION ${PNG_LIB_NAME} LOCATION_${CMAKE_BUILD_TYPE})

       CREATE_SYMLINK(${BUILD_TARGET_LOCATION} libpng${CMAKE_IMPORT_LIBRARY_SUFFIX})

       install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng${CMAKE_IMPORT_LIBRARY_SUFFIX}

         DESTINATION ${CMAKE_INSTALL_LIBDIR})

    endif(CYGWIN OR MINGW)

    if(NOT WIN32)

      get_target_property(BUILD_TARGET_LOCATION ${PNG_LIB_NAME} LOCATION_${CMAKE_BUILD_TYPE})

      CREATE_SYMLINK(${BUILD_TARGET_LOCATION} libpng${CMAKE_SHARED_LIBRARY_SUFFIX})

      install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng${CMAKE_SHARED_LIBRARY_SUFFIX}

         DESTINATION ${CMAKE_INSTALL_LIBDIR})

    endif(NOT WIN32)

  endif(PNG_SHARED)

  if(PNG_STATIC)

    if(NOT WIN32 OR CYGWIN OR MINGW)

      get_target_property(BUILD_TARGET_LOCATION ${PNG_LIB_NAME_STATIC} LOCATION_${CMAKE_BUILD_TYPE})

      CREATE_SYMLINK(${BUILD_TARGET_LOCATION} libpng${CMAKE_STATIC_LIBRARY_SUFFIX})

      install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng${CMAKE_STATIC_LIBRARY_SUFFIX}

         DESTINATION ${CMAKE_INSTALL_LIBDIR})

    endif(NOT WIN32 OR CYGWIN OR MINGW)

 endif()

endif()

if(NOT SKIP_INSTALL_HEADERS AND NOT SKIP_INSTALL_ALL )

  install(FILES ${libpng_public_hdrs}   DESTINATION include)

  install(FILES ${libpng_public_hdrs}   DESTINATION include/${PNGLIB_NAME})

endif()

if(NOT SKIP_INSTALL_EXECUTABLES AND NOT SKIP_INSTALL_ALL )

  if(NOT WIN32 OR CYGWIN OR MINGW)

    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/libpng-config DESTINATION bin)

    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config

            DESTINATION bin)

  endif(NOT WIN32 OR CYGWIN OR MINGW)

endif()

if(NOT SKIP_INSTALL_FILES AND NOT SKIP_INSTALL_ALL )

  # Install man pages

  if(NOT PNG_MAN_DIR)

    set(PNG_MAN_DIR "share/man")

  endif()

  install(FILES libpng.3 libpngpf.3      DESTINATION ${PNG_MAN_DIR}/man3)

  install(FILES png.5                    DESTINATION ${PNG_MAN_DIR}/man5)

  # Install pkg-config files

  if(NOT WIN32 OR CYGWIN OR MINGW)

    install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng.pc

            DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig)

    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/libpng-config

            DESTINATION bin)

    install(FILES ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}.pc

            DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig)

    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config

            DESTINATION bin)

  endif(NOT WIN32 OR CYGWIN OR MINGW)

endif()

# On versions of CMake that support it, create an export file CMake

# users can include() to import our targets

if(PNG_EXPORT_RULE AND NOT SKIP_INSTALL_EXPORT AND NOT SKIP_INSTALL_ALL )

  install(EXPORT libpng DESTINATION lib/libpng FILE lib${PNG_LIB_NAME}.cmake)

endif()

# what's with libpng-manual.txt and all the extra files?

# UNINSTALL

# do we need this?

# DIST

# do we need this?

# to create msvc import lib for mingw compiled shared lib

# pexports libpng.dll > libpng.def

# lib /def:libpng.def /machine:x86