cmake_minimum_required(VERSION 2.4.3)

set(CMAKE_ALLOW_LOOSE_LOOP_CONSTRUCTS true)

if(UNIX AND NOT DEFINED CMAKE_BUILD_TYPE)

  set(CMAKE_BUILD_TYPE "RelWithDebInfo" CACHE STRING 

      "Choose the type of build, options are:

         None(CMAKE_CXX_FLAGS or CMAKE_C_FLAGS used)

         Debug

         Release

         RelWithDebInfo

         MinSizeRel.")

endif()

project(libpng C)

enable_testing()

# Copyright (C) 2007-2010 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

set(PNGLIB_MAJOR 1)

set(PNGLIB_MINOR 2)

set(PNGLIB_RELEASE 57)

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 library 'libm' not found - floating point support disabled")

  endif()

else()

  # not needed on windows

  set(M_LIBRARY "")

endif()

# COMMAND LINE OPTIONS

if(DEFINED PNG_SHARED)

  option(PNG_SHARED "Build shared lib" ${PNG_SHARED})

else()

  option(PNG_SHARED "Build shared lib" ON)

endif()

if(DEFINED PNG_STATIC)

  option(PNG_STATIC "Build static lib" ${PNG_STATIC})

else()

  option(PNG_STATIC "Build static lib" ON)

endif()

if(MINGW)

  option(PNG_TESTS  "Build pngtest" NO)

else()

  option(PNG_TESTS  "Build pngtest" YES)

endif()

option(PNG_NO_CONSOLE_IO "FIXME" YES)

option(PNG_NO_STDIO      "FIXME" YES)

option(PNG_DEBUG         "Build with debug output" NO)

option(PNGARG            "FIXME" YES)

#TODO:

# PNG_CONSOLE_IO_SUPPORTED

# maybe needs improving, but currently I don't know when we can enable what :)

set(png_asm_tmp "OFF")

if(NOT WIN32)

  find_program(uname_executable NAMES uname PATHS /bin /usr/bin /usr/local/bin)

  if(uname_executable)

    exec_program(${uname_executable}

                 ARGS --machine OUTPUT_VARIABLE uname_output)

    if("uname_output" MATCHES "^.*i[1-9]86.*$")

      set(png_asm_tmp "ON")

    else("uname_output" MATCHES "^.*i[1-9]86.*$")

      set(png_asm_tmp "OFF")

    endif("uname_output" MATCHES "^.*i[1-9]86.*$")

  endif(uname_executable)

else()

  # this env var is normally only set on win64

  set(TEXT "ProgramFiles(x86)")

  if("$ENV{${TEXT}}" STREQUAL "")

    set(png_asm_tmp "ON")

  endif("$ENV{${TEXT}}" STREQUAL "")

endif()

# SET LIBNAME

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

# to distinguish between debug and release lib

set(CMAKE_DEBUG_POSTFIX "d")

# OUR SOURCES

set(libpng_sources

  png.h

  pngconf.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

)

# SOME NEEDED DEFINITIONS

add_definitions(-DPNG_CONFIGURE_LIBPNG)

if(_AIX)

  add_definitions(-D_ALL_SOURCE)

endif(_AIX)

if(MSVC)

  add_definitions(-DPNG_NO_MODULEDEF -D_CRT_SECURE_NO_DEPRECATE)

endif(MSVC)

if(PNG_SHARED OR  NOT MSVC)

  #if building msvc static this has NOT to be defined

  add_definitions(-DZLIB_DLL)

endif()

add_definitions(-DLIBPNG_NO_MMX)

add_definitions(-DPNG_NO_MMX_CODE)

if(PNG_CONSOLE_IO_SUPPORTED)

  add_definitions(-DPNG_CONSOLE_IO_SUPPORTED)

endif()

if(PNG_NO_CONSOLE_IO)

  add_definitions(-DPNG_NO_CONSOLE_IO)

endif()

if(PNG_NO_STDIO)

  add_definitions(-DPNG_NO_STDIO)

endif()

if(PNG_DEBUG)

  add_definitions(-DPNG_DEBUG)

endif()

if(NOT M_LIBRARY AND NOT WIN32)

  add_definitions(-DPNG_NO_FLOATING_POINT_SUPPORTED)

endif()

# NOW BUILD OUR TARGET

include_directories(${CMAKE_CURRENT_SOURCE_DIR} ${ZLIB_INCLUDE_DIR})

if(PNG_SHARED)

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

  if(MSVC)

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

    set_target_properties(${PNG_LIB_NAME} PROPERTIES 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})

  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()

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)

endif()

# CREATE PKGCONFIG FILES

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

set(prefix      ${CMAKE_INSTALL_PREFIX})

set(exec_prefix ${CMAKE_INSTALL_PREFIX})

set(libdir      ${CMAKE_INSTALL_PREFIX}/lib)

set(includedir  ${CMAKE_INSTALL_PREFIX}/include)

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

  ${CMAKE_CURRENT_BINARY_DIR}/libpng.pc)

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

  ${CMAKE_CURRENT_BINARY_DIR}/libpng-config)

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

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

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

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

# SET UP LINKS

if(PNG_SHARED)

  set_target_properties(${PNG_LIB_NAME} PROPERTIES

#   VERSION 0.${PNGLIB_RELEASE}.1.2.57

    VERSION 0.${PNGLIB_RELEASE}.0

    SOVERSION 0

    CLEAN_DIRECT_OUTPUT 1)

endif()

if(PNG_STATIC)

  if(NOT WIN32)

    # that's uncool on win32 - it overwrites our static import lib...

    set_target_properties(${PNG_LIB_NAME_STATIC} PROPERTIES

      OUTPUT_NAME ${PNG_LIB_NAME}

      CLEAN_DIRECT_OUTPUT 1)

  endif()

endif()

# INSTALL

if(NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL )

  if(PNG_SHARED)

    install(TARGETS ${PNG_LIB_NAME}

            RUNTIME DESTINATION bin

            LIBRARY DESTINATION lib

            ARCHIVE DESTINATION lib)

  endif()

  if(PNG_STATIC)

    install(TARGETS ${PNG_LIB_NAME_STATIC}

            LIBRARY DESTINATION lib

            ARCHIVE DESTINATION lib)

  endif()

endif()

if(NOT SKIP_INSTALL_HEADERS AND NOT SKIP_INSTALL_ALL )

  install(FILES png.h pngconf.h         DESTINATION include)

  install(FILES png.h pngconf.h         DESTINATION include/${PNGLIB_NAME})

endif()

if(NOT SKIP_INSTALL_EXECUTABLES AND NOT SKIP_INSTALL_ALL )

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

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

          DESTINATION bin)

endif()

if(NOT SKIP_INSTALL_FILES AND NOT SKIP_INSTALL_ALL )

  # Install man pages

  install(FILES libpng.3 libpngpf.3             DESTINATION man/man3)

  install(FILES png.5                           DESTINATION man/man5)

  # Install pkg-config files

  install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng.pc

          DESTINATION lib/pkgconfig)

  install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng-config

          DESTINATION bin)

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

          DESTINATION lib/pkgconfig)

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

          DESTINATION bin)

endif()

# what's with libpng.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