[system-dependencies] Add CMake dependency. (#920)

Make.config

@@ -62,6 +62,10 @@ MIN_XAMARIN_STUDIO_URL=https://files.xamarin.com/~rolf/XamarinStudio-6.1.0.4373.
 MIN_XAMARIN_STUDIO_VERSION=6.1.0.4373
 MAX_XAMARIN_STUDIO_VERSION=6.2.0.9999
 
+# Minimum CMake version
+MIN_CMAKE_URL=https://cmake.org/files/v3.6/cmake-3.6.2-Darwin-x86_64.dmg
+MIN_CMAKE_VERSION=2.8.8
+
 # Minimum OSX versions
 MIN_OSX_BUILD_VERSION=10.11
 MIN_OSX_VERSION_FOR_IOS=10.11

README.md

@@ -21,6 +21,17 @@ You can download continuous builds of our main development branches from [our wi
       $ brew update
       $ brew install libtool autoconf automake bison flex
 
+* CMake
+
+  You can use brew, or download manually from [cmake.org](https://cmake.org/download/).
+
+  CMake must be in PATH, so if you install it somewhere else, you'll have to
+  fix up your PATH accordingly (not necessary if installed using brew).
+
+  To install using brew:
+
+      $ brew install cmake
+
 * Xcode
 
   To build the Xamarin.iOS and Xamarin.Mac SDKs you need a certain version of Xcode.

system-dependencies.sh

@@ -52,6 +52,10 @@ while ! test -z $1; do
 			IGNORE_AUTOTOOLS=1
 			shift
 			;;
+		--ignore-cmake)
+			IGNORE_CMAKE=1
+			shift
+			;;
 		*)
 			echo "Unknown argument: $1"
 			exit 1
@@ -455,6 +459,26 @@ function check_osx_version () {
 	ok "Found OSX $ACTUAL_OSX_VERSION (at least $MIN_OSX_BUILD_VERSION is required)"
 }
 
+function check_cmake () {
+	if ! test -z $IGNORE_CMAKE; then return; fi
+
+	local MIN_CMAKE_VERSION=`grep MIN_CMAKE_VERSION= Make.config | sed 's/.*=//'`
+	local CMAKE_URL=`grep CMAKE_URL= Make.config | sed 's/.*=//'`
+
+	if ! cmake --version &> /dev/null; then
+		fail "You must install CMake ($CMAKE_URL)"
+		return
+	fi
+
+	ACTUAL_CMAKE_VERSION=$(cmake --version | grep "cmake version" | sed 's/cmake version //')
+	if ! is_at_least_version $ACTUAL_CMAKE_VERSION $MIN_CMAKE_VERSION; then
+		fail "You must have at least CMake $MIN_CMAKE_VERSION (found $ACTUAL_CMAKE_VERSION)"
+		return
+	fi
+
+	ok "Found CMake $ACTUAL_CMAKE_VERSION (at least $MIN_CMAKE_VERSION is required)"
+}
+
 echo "Checking system..."
 
 check_osx_version
@@ -462,6 +486,7 @@ check_xcode
 check_autotools
 check_mono
 check_xamarin_studio
+check_cmake
 
 if test -z $FAIL; then
 	echo "System check succeeded"