Get CMake to support Android and iOS platforms

BUILDING_ANDROID.md

@@ -0,0 +1,80 @@
+Building for Android
+---
+
+## Dependencies
+
+* CMake 3.10 or later
+* A build tool Ninja
+* A C++11-compliant compiler
+* GCC 7.3 or later
+* Clang 3.3 or later
+
+## Supported Crypto solutions
+* OpenSSL 1.1.1 or later
+* libsodium is not supported yet.
+
+## NOTE
+
+The Cmake file fetches and builds the required libraries for Android: Protobuf and OpenSSL. (not libsodium yet)
+
+## Build by a Linux machine
+It is tested at a local Linux machine Debian 12.
+
+Download Android NDK from Google's site, extract it
+
+https://dl.google.com/android/repository/android-ndk-r15c-linux-x86_64.zip~/android-ndk-r15c
+
+Install ncurses
+```
+sudo apt-get install libncurses5
+```
+
+Clone GameNetworkingSockets and create build folder
+```
+git clone https://github.com/ValveSoftware/GameNetworkingSockets.git
+cd GameNetworkingSockets
+mkdir buildAndroid
+cd buildAndroid
+```
+
+Configure GameNetworkingSockets
+```
+sudo cmake -DCMAKE_TOOLCHAIN_FILE=../../android-ndk-r15c/build/cmake/android.toolchain.cmake -DANDROID_NDK_RPATH=../../android-ndk-r15c -DANDROID_ABI=arm64-v8a -DANDROID_PLATFORM=android-21 -DCMAKE_CXX_FLAGS=-std=c++11 -DCMAKE_POSITION_INDEPENDENT_CODE=ON -Dprotobuf_BUILD_TESTS=OFF -DCMAKE_BUILD_TYPE=Release -DANDROID_STL=c++_static -DOpenSSLTag=OpenSSL_1_1_1e -DProtobufTag=v3.21.6 -G Ninja ..
+```
+Note: Configure will fetch and build Protobuf and OpenSSL libraries for Android.
+
+* -DCMAKE_TOOLCHAIN_FILE: Path to the toolchain cmake file for android NDK
+* -DANDROID_NDK_RPATH: Relative path to the android NDK
+* -DANDROID_ABI: Can be arm64-v8a or armeabi-v7a, both supports.
+* -DANDROID_PLATFORM: Android platform
+* -DCMAKE_BUILD_TYPE: can be Release or Debug
+* -DOpenSSLTag: OpenSSL git tag
+* -DProtobufTag: Protobuf git tag
+
+Finally, build GameNetworkingSockets
+```
+sudo ninja
+```
+
+## After build
+**Folder structure**
+
+android-ndk-r15c/</br>
+GameNetworkingSockets/</br>
+&nbsp;&nbsp;&nbsp;&nbsp;buildAndroid/</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;bin/</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**libGameNetworkingSockets.so**</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;src/</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**libGameNetworkingSockets_s.a**</br>
+&nbsp;&nbsp;&nbsp;&nbsp;_deps/</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;protobuf-build/</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**libprotoc.a**</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**libprotobuf.a**</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**libprotobuf-lite.a**</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;openssl-src/</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**libssl.a**</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**libcrypto.a**</br>
+
+## Build by a Windows machine
+
+I believe with the right shell, MSYS2 or WSL, it should be building properly with the Linux commands above.

BUILDING_IOS.md

@@ -0,0 +1,76 @@
+Building for iOS
+---
+
+## Dependencies
+
+* CMake 3.10 or later
+* A build tool Ninja
+* A C++11-compliant compiler
+* GCC 7.3 or later
+* Clang 3.3 or later
+* A Macintosh
+
+## Supported Crypto solutions
+* OpenSSL 1.1.1 or later
+* libsodium is not supported yet.
+
+## NOTE
+
+The Cmake file fetches and builds the required libraries for iOS: Protobuf and OpenSSL. (not libsodium yet)
+It requires a MacOS platform.
+
+## Build with a Mac
+
+Install Brew if not installed.
+```
+/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
+```
+
+Install ninja by brew
+```
+brew install ninja llvm
+```
+Install xcode
+```
+xcode-select --install
+```
+Clone GameNetworkingSockets and create build folder
+```
+git clone https://github.com/ValveSoftware/GameNetworkingSockets.git
+cd GameNetworkingSockets
+mkdir buildiOS
+cd buildiOS
+```
+
+Configure GameNetworkingSockets
+```
+sudo cmake -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphoneos -DCMAKE_OSX_ARCHITECTURES=arm64 -DCMAKE_POSITION_INDEPENDENT_CODE=ON -Dprotobuf_BUILD_TESTS=OFF -DCMAKE_BUILD_TYPE=Release -DOpenSSLTag=OpenSSL_1_1_1e -DProtobufTag=v3.21.6 -DCMAKE_OSX_DEPLOYMENT_TARGET=11.0 -G Ninja ..
+```
+Note: Configure will fetch and build Protobuf and OpenSSL libraries for iOS.
+
+* -DCMAKE_BUILD_TYPE: can be Release or Debug
+* -DOpenSSLTag: OpenSSL git tag
+* -DProtobufTag: Protobuf git tag
+
+Finally, build GameNetworkingSockets
+```
+sudo ninja
+```
+
+## After build
+**Folder structure**
+
+GameNetworkingSockets/</br>
+&nbsp;&nbsp;&nbsp;&nbsp;buildiOS/</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;bin/</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**libGameNetworkingSockets.dylib**</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;src/</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**libGameNetworkingSockets_s.a**</br>
+&nbsp;&nbsp;&nbsp;&nbsp;_deps/</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;protobuf-build/</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**libprotoc.a**</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**libprotobuf.a**</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**libprotobuf-lite.a**</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;openssl-src/</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**libssl.a**</br>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**libcrypto.a**</br>

CMakeLists.txt

@@ -96,6 +96,166 @@ if (WIN32)
 	endif()
 endif()
 
+if (ANDROID OR APPLE)
+	#
+	# Fetch Protobuf, configure it and build it for the desired platform. Supported platforms: iOS, Android and MacOS
+	# Build it twice, one at config time for current platform and one at compile time for desired platform
+	# So we can protoc source files before compile time with the current platform (Otherwise protoc may be built for different arch. than your building machine cpu)
+	#
+	message( "Fetching protobuf... ")
+	include(FetchContent)
+	FetchContent_GetProperties(Protobuf)
+	if(NOT Protobuf_POPULATED)
+
+		FetchContent_Declare(Protobuf
+			GIT_REPOSITORY https://github.com/protocolbuffers/protobuf.git
+			GIT_TAG        ${ProtobufTag}
+			OVERRIDE_FIND_PACKAGE
+			)
+	FetchContent_MakeAvailable(Protobuf)
+	endif ()
+
+	message( "Configuring protobuf... ")
+
+	# Some pre-configs for Protobuf config and buid operations
+	if (UNIX)
+	set (fileName "build.sh")
+	set (fileHeader "#!/bin/sh\n")
+	endif()
+
+	if (CMAKE_SYSTEM_NAME MATCHES Darwin)
+		set (depsBuildFolderName buildMacOS)
+	elseif (CMAKE_SYSTEM_NAME MATCHES iOS)
+		set (depsBuildFolderName buildiOS)
+	elseif (ANDROID)
+		set (depsBuildFolderName buildAndroid)
+	endif()
+
+	# Configure Protobuf for desired platform
+	file (MAKE_DIRECTORY ${PROJECT_BINARY_DIR}/_deps/protobuf-src/${depsBuildFolderName})
+	file (WRITE ${PROJECT_BINARY_DIR}/_deps/protobuf-src/${depsBuildFolderName}/${fileName} ${fileHeader})
+
+	if (ANDROID)
+
+		file (APPEND ${PROJECT_BINARY_DIR}/_deps/protobuf-src/${depsBuildFolderName}/${fileName} "cmake -DCMAKE_TOOLCHAIN_FILE=../../${ANDROID_NDK_RPATH}/build/cmake/android.toolchain.cmake -DANDROID_ABI=${ANDROID_ABI} -DANDROID_PLATFORM=android-21 -DCMAKE_CXX_FLAGS=-std=c++14 -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE} -Dprotobuf_BUILD_TESTS=OFF -DCMAKE_POSITION_INDEPENDENT_CODE=ON -DANDROID_STL=c++_static -G Ninja ..")
+
+	elseif (CMAKE_SYSTEM_NAME MATCHES Darwin) #MACOS
+		file (APPEND ${PROJECT_BINARY_DIR}/_deps/protobuf-src/${depsBuildFolderName}/${fileName} "cmake -DCMAKE_OSX_DEPLOYMENT_TARGET=${CMAKE_OSX_DEPLOYMENT_TARGET} -G Ninja ..")
+	elseif(CMAKE_SYSTEM_NAME MATCHES iOS)  #iOS
+		set( OPENSSL_TARGET_ARCHITECTURES_iphoneos arm64 )
+		file (APPEND ${PROJECT_BINARY_DIR}/_deps/protobuf-src/${depsBuildFolderName}/${fileName} "cmake -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphoneos -DCMAKE_OSX_ARCHITECTURES=arm64 -DCMAKE_OSX_DEPLOYMENT_TARGET=${CMAKE_OSX_DEPLOYMENT_TARGET} -Dprotobuf_BUILD_TESTS=OFF -DCMAKE_POSITION_INDEPENDENT_CODE=ON -G Ninja ..
+sudo cmake --build . --parallel 10")
+	endif()
+
+	# Configure Protobuf for current platform
+	file (MAKE_DIRECTORY ${PROJECT_BINARY_DIR}/_deps/protobuf-src/buildCurrentPlatform)
+	file (WRITE ${PROJECT_BINARY_DIR}/_deps/protobuf-src/buildCurrentPlatform/${fileName} ${fileHeader})
+
+	if (ANDROID)
+	file (APPEND ${PROJECT_BINARY_DIR}/_deps/protobuf-src/buildCurrentPlatform/${fileName} "cmake -G Ninja ..
+	sudo cmake --build . --parallel 10")
+	elseif (CMAKE_SYSTEM_NAME MATCHES Darwin) #MACOS
+	file (APPEND ${PROJECT_BINARY_DIR}/_deps/protobuf-src/buildCurrentPlatform/${fileName} "cmake -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE} -DCMAKE_OSX_DEPLOYMENT_TARGET=${CMAKE_OSX_DEPLOYMENT_TARGET} -DCMAKE_CXX_COMPILER=clang++ -DCMAKE_C_COMPILER=clang -Dprotobuf_BUILD_TESTS=OFF -DCMAKE_CXX_FLAGS=\"-fpic -O2\" -DCMAKE_POSITION_INDEPENDENT_CODE=ON -G Ninja ..
+	sudo cmake --build . --parallel 10")
+	elseif(CMAKE_SYSTEM_NAME MATCHES iOS)  #iOS
+	file (APPEND ${PROJECT_BINARY_DIR}/_deps/protobuf-src/buildCurrentPlatform/${fileName} "cmake -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE} -DCMAKE_CXX_COMPILER=clang++ -DCMAKE_C_COMPILER=clang -Dprotobuf_BUILD_TESTS=OFF -DCMAKE_CXX_FLAGS=\"-fpic -O2\" -DCMAKE_POSITION_INDEPENDENT_CODE=ON -G Ninja ..
+	sudo cmake --build . --parallel 10")
+	endif()
+
+	if (UNIX)
+	# Build Protobuf for desired platform
+	execute_process (COMMAND bash "-c" "bash ${fileName}"
+	WORKING_DIRECTORY ${PROJECT_BINARY_DIR}/_deps/protobuf-src/${depsBuildFolderName}
+	RESULT_VARIABLE errorval )
+
+	# Build Protobuf for cırrent platform
+	execute_process (COMMAND bash "-c" "bash ${fileName}"
+	WORKING_DIRECTORY ${PROJECT_BINARY_DIR}/_deps/protobuf-src/buildCurrentPlatform
+	RESULT_VARIABLE errorval )
+	endif ()
+
+	#
+	# Fetch OpenSSL, configure it and build it, supported platforms: iOS, Android and MacOS
+	#
+	message( "Fetching & Building OpenSSL... ")
+	FetchContent_GetProperties(OpenSSL)
+	if(NOT OpenSSL_POPULATED)
+
+		FetchContent_Declare(OpenSSL
+			GIT_REPOSITORY https://github.com/openssl/openssl.git
+			GIT_TAG        ${OpenSSLTag}
+			OVERRIDE_FIND_PACKAGE
+			)
+	FetchContent_MakeAvailable(OpenSSL)
+	endif ()
+
+	#
+	# Set some paths for fetched libraries
+	#
+
+	set(OPENSSL_CRYPTO_LIBRARY ${PROJECT_BINARY_DIR}/_deps/openssl-src/libcrypto.so)
+	set(OPENSSL_INCLUDE_DIR ${PROJECT_BINARY_DIR}/_deps/openssl-src/include)
+	include_directories(${OPENSSL_INCLUDE_DIR})
+
+	# Configure OpenSSL for desired platform
+	file (WRITE ${PROJECT_BINARY_DIR}/_deps/openssl-src/${fileName} ${fileHeader})
+
+	if (ANDROID)
+		if (ANDROID_ABI STREQUAL "arm64-v8a")
+			set (64BitArg "android-arm64")
+		else()
+			set (64BitArg "android-arm")
+		endif()
+
+		if(CMAKE_BUILD_TYPE STREQUAL "Debug")
+			set (BuildType "--debug")
+		else()
+			set (BuildType "--release")
+		endif()
+		file (APPEND ${PROJECT_BINARY_DIR}/_deps/openssl-src/${fileName} "export ANDROID_NDK_HOME=../../${ANDROID_NDK_RPATH}
+PATH=$ANDROID_NDK_HOME/toolchains/aarch64-linux-android-4.9/prebuilt/linux-x86_64/bin:$PATH
+PATH=$ANDROID_NDK_HOME/toolchains/llvm/prebuilt/linux-x86_64/bin:$PATH
+./Configure no-tests ${64BitArg} -D__ANDROID_API__=21 ${BuildType}
+make")
+
+	elseif (CMAKE_SYSTEM_NAME MATCHES Darwin) 
+		file (APPEND ${PROJECT_BINARY_DIR}/_deps/openssl-src/${fileName} "export SDKROOT=\"$(xcrun --sdk macosx --show-sdk-path)\"
+./Configure darwin64-x86_64-cc no-shared enable-ec_nistp_64_gcc_128 no-ssl2 no-ssl3 no-comp ${BuildType}
+make")
+	elseif (CMAKE_SYSTEM_NAME MATCHES iOS) 
+		set( OPENSSL_TARGET_ARCHITECTURES_iphoneos arm64 )
+		# Specify the minimum iOS version
+		file (APPEND ${PROJECT_BINARY_DIR}/_deps/openssl-src/${fileName} "export CC=clang;
+export CROSS_TOP=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer
+export CROSS_SDK=iPhoneOS.sdk
+PATH=/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin:$PATH	
+./Configure no-tests ios64-cross no-shared no-dso no-hw no-engine ${BuildType}
+make")
+	endif()
+
+	# Build OpenSSL for desired platform
+	if (UNIX)
+	execute_process (COMMAND bash "-c" "bash ${fileName}"
+	WORKING_DIRECTORY ${PROJECT_BINARY_DIR}/_deps/openssl-src
+	RESULT_VARIABLE errorval )
+	endif()
+
+	if (WIN32)
+	execute_process (COMMAND cmd "-c" "${fileName}"
+	WORKING_DIRECTORY ${PROJECT_BINARY_DIR}/_deps/openssl-src
+	RESULT_VARIABLE errorval )
+	endif()
+
+	#
+	# Optional: Set -s flag to strip(removes symbols) the output library (for ex: libGameNetworkingSockets.so)
+	#
+	if (ANDROID)
+		set(CMAKE_C_FLAGS_RELEASE "${CMAKE_C_FLAGS_RELEASE} -s")
+		set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -s")
+	endif ()
+
+endif (ANDROID OR APPLE)
+
 if (USE_CRYPTO STREQUAL "OpenSSL")
 	# Match the OpenSSL runtime to our setting.
 	# Note that once found the library paths are cached and will not change if the option is changed.
@@ -114,7 +274,13 @@ if (USE_CRYPTO STREQUAL "OpenSSL")
 		if(WIN32 AND OPENSSL_USE_STATIC_LIBS)
 			list(APPEND CMAKE_REQUIRED_LIBRARIES ws2_32 crypt32)
 		endif()
-		check_symbol_exists(EVP_MD_CTX_free openssl/evp.h OPENSSL_NEW_ENOUGH)
+		#Bypassing "EVP_MD_CTX_free" check for Android and iOS
+		#because it fails even OpenSSL version is higher than 1.1.1
+		if (NOT ANDROID AND NOT APPLE)
+			check_symbol_exists(EVP_MD_CTX_free openssl/evp.h OPENSSL_NEW_ENOUGH)
+		else()
+			set(OPENSSL_NEW_ENOUGH TRUE)
+		endif ()
 		if (NOT OPENSSL_NEW_ENOUGH)
 			message(FATAL_ERROR "Cannot find EVP_MD_CTX_free in OpenSSL headers/libs for the target architecture.  Check that you're using OpenSSL 1.1.0 or later.")
 		endif()
@@ -161,6 +327,8 @@ function(set_target_common_gns_properties TGT)
 		target_compile_definitions(${TGT} PUBLIC LINUX)
 	elseif(CMAKE_SYSTEM_NAME MATCHES Darwin)
 		target_compile_definitions(${TGT} PUBLIC OSX)
+	elseif(CMAKE_SYSTEM_NAME MATCHES iOS)
+		target_compile_definitions(${TGT} PUBLIC OSX)
 	elseif(CMAKE_SYSTEM_NAME MATCHES FreeBSD)
 		target_compile_definitions(${TGT} PUBLIC FREEBSD)
 	elseif(CMAKE_SYSTEM_NAME MATCHES Windows)
@@ -189,6 +357,8 @@ function(set_target_common_gns_properties TGT)
 				)
 			target_compile_options(${TGT} PRIVATE -fno-stack-protector)
 		endif()
+		elseif(CMAKE_SYSTEM_NAME MATCHES Android)
+		target_compile_definitions(${TGT} PUBLIC ANDROID)
 	else()
 		message(FATAL_ERROR "Could not identify your target operating system")
 	endif()