cmake/iOS.cmake

# This file is based off of the Platform/Darwin.cmake and Platform/UnixPaths.cmake
# files which are included with CMake 2.8.4
# It has been altered for iOS development

# Options:
#
# IOS_PLATFORM = OS (default) or SIMULATOR
#   This decides if SDKS will be selected from the iPhoneOS.platform or iPhoneSimulator.platform folders
#   OS - the default, used to build for iPhone and iPad physical devices, which have an arm arch.
#   SIMULATOR - used to build for the Simulator platforms, which have an x86 arch.
#
# CMAKE_IOS_DEVELOPER_ROOT = automatic(default) or /path/to/platform/Developer folder
#   By default this location is automatcially chosen based on the IOS_PLATFORM value above.
#   If set manually, it will override the default location and force the user of a particular Developer Platform
#
# CMAKE_IOS_SDK_ROOT = automatic(default) or /path/to/platform/Developer/SDKs/SDK folder
#   By default this location is automatcially chosen based on the CMAKE_IOS_DEVELOPER_ROOT value.
#   In this case it will always be the most up-to-date SDK found in the CMAKE_IOS_DEVELOPER_ROOT path.
#   If set manually, this will force the use of a specific SDK version

# Macros:
#
# set_xcode_property (TARGET XCODE_PROPERTY XCODE_VALUE)
#  A convenience macro for setting xcode specific properties on targets
#  example: set_xcode_property (myioslib IPHONEOS_DEPLOYMENT_TARGET "3.1")
#
# find_host_package (PROGRAM ARGS)
#  A macro used to find executable programs on the host system, not within the iOS environment.
#  Thanks to the android-cmake project for providing the command

# Standard settings
set(CMAKE_SYSTEM_NAME Darwin)
set(CMAKE_SYSTEM_VERSION 1)
set(UNIX True)
set(APPLE True)
set(IOS True)

# Required as of cmake 2.8.10
set(CMAKE_OSX_DEPLOYMENT_TARGET "" CACHE STRING "Force unset of the deployment target for iOS" FORCE)

# Determine the cmake host system version so we know where to find the iOS SDKs
find_program(CMAKE_UNAME uname /bin /usr/bin /usr/local/bin)
if(CMAKE_UNAME)
    exec_program(uname ARGS -r OUTPUT_VARIABLE CMAKE_HOST_SYSTEM_VERSION)
    string(REGEX REPLACE "^([0-9]+)\\.([0-9]+).*$" "\\1" DARWIN_MAJOR_VERSION "${CMAKE_HOST_SYSTEM_VERSION}")
endif(CMAKE_UNAME)

# Force the compilers to gcc for iOS
set(CMAKE_C_COMPILER /usr/bin/gcc CACHE STRING "")
set(CMAKE_CXX_COMPILER /usr/bin/g++ CACHE STRING "")
set(CMAKE_AR ar CACHE FILEPATH "" FORCE)
set(CMAKE_RANLIB ranlib CACHE FILEPATH "" FORCE)
set(PKG_CONFIG_EXECUTABLE pkg-config CACHE FILEPATH "" FORCE)

# Setup iOS platform unless specified manually with IOS_PLATFORM
if(NOT DEFINED IOS_PLATFORM)
    set(IOS_PLATFORM "OS")
endif(NOT DEFINED IOS_PLATFORM)
set(IOS_PLATFORM ${IOS_PLATFORM} CACHE STRING "Type of iOS Platform")

# Check the platform selection and setup for developer root
if(${IOS_PLATFORM} STREQUAL "OS")
    set(IOS_PLATFORM_LOCATION "iPhoneOS.platform")
    set(XCODE_IOS_PLATFORM iphoneos)

    # This causes the installers to properly locate the output libraries
    set(CMAKE_XCODE_EFFECTIVE_PLATFORMS "-iphoneos")
elseif(${IOS_PLATFORM} STREQUAL "SIMULATOR")
    set(IOS_PLATFORM_LOCATION "iPhoneSimulator.platform")
    set(XCODE_IOS_PLATFORM iphonesimulator)

    # This causes the installers to properly locate the output libraries
    set(CMAKE_XCODE_EFFECTIVE_PLATFORMS "-iphonesimulator")
elseif(${IOS_PLATFORM} STREQUAL "WATCHOS")
    set(IOS_PLATFORM_LOCATION "WatchOS.platform")
    set(XCODE_IOS_PLATFORM watchos)

    # This causes the installers to properly locate the output libraries
    set(CMAKE_XCODE_EFFECTIVE_PLATFORMS "-watchos")
else(${IOS_PLATFORM} STREQUAL "OS")
    message(FATAL_ERROR
            "Unsupported IOS_PLATFORM value selected. "
            "Please choose OS, SIMULATOR, or WATCHOS.")
endif()

# All iOS/Darwin specific settings - some may be redundant
set(CMAKE_SHARED_LIBRARY_PREFIX "lib")
set(CMAKE_SHARED_LIBRARY_SUFFIX ".dylib")
set(CMAKE_SHARED_MODULE_PREFIX "lib")
set(CMAKE_SHARED_MODULE_SUFFIX ".so")
set(CMAKE_MODULE_EXISTS 1)
set(CMAKE_DL_LIBS "")

set(CMAKE_C_OSX_COMPATIBILITY_VERSION_FLAG "-compatibility_version ")
set(CMAKE_C_OSX_CURRENT_VERSION_FLAG "-current_version ")
set(CMAKE_CXX_OSX_COMPATIBILITY_VERSION_FLAG "${CMAKE_C_OSX_COMPATIBILITY_VERSION_FLAG}")
set(CMAKE_CXX_OSX_CURRENT_VERSION_FLAG "${CMAKE_C_OSX_CURRENT_VERSION_FLAG}")

if(IOS_DEPLOYMENT_TARGET)
  set(XCODE_IOS_PLATFORM_VERSION_FLAGS "-m${XCODE_IOS_PLATFORM}-version-min=${IOS_DEPLOYMENT_TARGET}")
endif()

# Hidden visibilty is required for cxx on iOS 
set(CMAKE_C_FLAGS_INIT "${XCODE_IOS_PLATFORM_VERSION_FLAGS}")
set(CMAKE_CXX_FLAGS_INIT "${XCODE_IOS_PLATFORM_VERSION_FLAGS} -fvisibility-inlines-hidden")

set(CMAKE_C_LINK_FLAGS "${XCODE_IOS_PLATFORM_VERSION_FLAGS} -Wl,-search_paths_first ${CMAKE_C_LINK_FLAGS}")
set(CMAKE_CXX_LINK_FLAGS "${XCODE_IOS_PLATFORM_VERSION_FLAGS} -Wl,-search_paths_first ${CMAKE_CXX_LINK_FLAGS}")

set(CMAKE_PLATFORM_HAS_INSTALLNAME 1)
set(CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS "-dynamiclib -headerpad_max_install_names")
set(CMAKE_SHARED_MODULE_CREATE_C_FLAGS "-bundle -headerpad_max_install_names")
set(CMAKE_SHARED_MODULE_LOADER_C_FLAG "-Wl,-bundle_loader,")
set(CMAKE_SHARED_MODULE_LOADER_CXX_FLAG "-Wl,-bundle_loader,")
set(CMAKE_FIND_LIBRARY_SUFFIXES ".dylib" ".so" ".a")

# hack: if a new cmake (which uses CMAKE_INSTALL_NAME_TOOL) runs on an old build tree
# (where install_name_tool was hardcoded) and where CMAKE_INSTALL_NAME_TOOL isn't in the cache
# and still cmake didn't fail in CMakeFindBinUtils.cmake (because it isn't rerun)
# hardcode CMAKE_INSTALL_NAME_TOOL here to install_name_tool, so it behaves as it did before, Alex
if(NOT DEFINED CMAKE_INSTALL_NAME_TOOL)
    find_program(CMAKE_INSTALL_NAME_TOOL install_name_tool)
endif(NOT DEFINED CMAKE_INSTALL_NAME_TOOL)

# Setup iOS deployment target
set(IOS_DEPLOYMENT_TARGET ${IOS_DEPLOYMENT_TARGET} CACHE STRING "Minimum iOS version")

# Setup iOS developer location unless specified manually with CMAKE_IOS_DEVELOPER_ROOT
# Note Xcode 4.3 changed the installation location, choose the most recent one available
exec_program(/usr/bin/xcode-select ARGS -print-path OUTPUT_VARIABLE CMAKE_XCODE_DEVELOPER_DIR)
set(XCODE_POST_43_ROOT "${CMAKE_XCODE_DEVELOPER_DIR}/Platforms/${IOS_PLATFORM_LOCATION}/Developer")
set(XCODE_PRE_43_ROOT "/Developer/Platforms/${IOS_PLATFORM_LOCATION}/Developer")
if(NOT DEFINED CMAKE_IOS_DEVELOPER_ROOT)
    if(EXISTS ${XCODE_POST_43_ROOT})
        set(CMAKE_IOS_DEVELOPER_ROOT ${XCODE_POST_43_ROOT})
    elseif(EXISTS ${XCODE_PRE_43_ROOT})
        set(CMAKE_IOS_DEVELOPER_ROOT ${XCODE_PRE_43_ROOT})
    endif(EXISTS ${XCODE_POST_43_ROOT})
endif(NOT DEFINED CMAKE_IOS_DEVELOPER_ROOT)
set(CMAKE_IOS_DEVELOPER_ROOT ${CMAKE_IOS_DEVELOPER_ROOT} CACHE PATH "Location of iOS Platform")

# Find and use the most recent iOS sdk unless specified manually with CMAKE_IOS_SDK_ROOT
if(NOT DEFINED CMAKE_IOS_SDK_ROOT)
    file(GLOB _CMAKE_IOS_SDKS "${CMAKE_IOS_DEVELOPER_ROOT}/SDKs/*")
    if(_CMAKE_IOS_SDKS) 
        list(SORT _CMAKE_IOS_SDKS)
        list(REVERSE _CMAKE_IOS_SDKS)
        list(GET _CMAKE_IOS_SDKS 0 CMAKE_IOS_SDK_ROOT)
    else(_CMAKE_IOS_SDKS)
        message(FATAL_ERROR "No iOS SDK's found in default search path ${CMAKE_IOS_DEVELOPER_ROOT}. Manually set CMAKE_IOS_SDK_ROOT or install the iOS SDK.")
    endif(_CMAKE_IOS_SDKS)
    message(STATUS "Toolchain using default iOS SDK: ${CMAKE_IOS_SDK_ROOT}")
endif(NOT DEFINED CMAKE_IOS_SDK_ROOT)
set(CMAKE_IOS_SDK_ROOT ${CMAKE_IOS_SDK_ROOT} CACHE PATH "Location of the selected iOS SDK")

# Set the sysroot default to the most recent SDK
set(CMAKE_OSX_SYSROOT ${CMAKE_IOS_SDK_ROOT} CACHE PATH "Sysroot used for iOS support")

# set the architecture for iOS 
if(IOS_PLATFORM STREQUAL "OS")
    set(DEFAULT_IOS_ARCH "arm64")
elseif(IOS_PLATFORM STREQUAL "SIMULATOR")
    set(DEFAULT_IOS_ARCH "x86_64")
elseif(IOS_PLATFORM STREQUAL "WATCHOS")
    set(DEFAULT_IOS_ARCH "armv7k;arm64_32")
endif()

set(IOS_ARCH ${DEFAULT_IOS_ARCH} CACHE string  "Build architecture for iOS")
set(CMAKE_OSX_ARCHITECTURES ${IOS_ARCH} CACHE string  "Build architecture for iOS")

# Set the find root to the iOS developer roots and to user defined paths
set(CMAKE_FIND_ROOT_PATH ${CMAKE_IOS_DEVELOPER_ROOT} ${CMAKE_IOS_SDK_ROOT} ${CMAKE_PREFIX_PATH} CACHE string  "iOS find search path root")

# default to searching for frameworks first
set(CMAKE_FIND_FRAMEWORK FIRST)

# set up the default search directories for frameworks
set(CMAKE_SYSTEM_FRAMEWORK_PATH
    ${CMAKE_IOS_SDK_ROOT}/System/Library/Frameworks
    ${CMAKE_IOS_SDK_ROOT}/System/Library/PrivateFrameworks
    ${CMAKE_IOS_SDK_ROOT}/Developer/Library/Frameworks
)

# only search the iOS sdks, not the remainder of the host filesystem
set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM ONLY)
set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)

# This little macro lets you set any XCode specific property
macro(set_xcode_property TARGET XCODE_PROPERTY XCODE_VALUE)
    set_property(TARGET ${TARGET} PROPERTY XCODE_ATTRIBUTE_${XCODE_PROPERTY} ${XCODE_VALUE})
endmacro(set_xcode_property)

# This macro lets you find executable programs on the host system
macro(find_host_package)
    set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
    set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY NEVER)
    set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE NEVER)
    set(IOS FALSE)

    find_package(${ARGN})

    set(IOS TRUE)
    set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM ONLY)
    set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
    set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
endmacro(find_host_package)