[xBuild] Support ToolsVersion 12

From VS2013, MSBuild is now decouple from the .NET Framework and is a separate redistributable. This means it has a new location and version numbering scheme. There are also some addition MSBuild properties because of this

mcs/class/Microsoft.Build.Engine/Microsoft.Build.BuildEngine/Engine.cs

@@ -117,6 +117,11 @@ void LoadDefaultToolsets ()
 #if NET_4_0
 			Toolsets.Add (new Toolset ("4.0",
 						ToolLocationHelper.GetPathToDotNetFramework (TargetDotNetFrameworkVersion.Version40)));
+#endif
+#if NET_4_5
+			Toolsets.Add (new Toolset("12.0",
+						ToolLocationHelper.GetMSBuildInstallPath ("12.0"),
+						ToolLocationHelper.GetPathToDotNetFramework (TargetDotNetFrameworkVersion.Version40)));
 #endif
 		}
 

mcs/class/Microsoft.Build.Engine/Microsoft.Build.BuildEngine/Project.cs

@@ -1029,7 +1029,17 @@ void InitializeProperties (string effective_tools_version)
 			SetExtensionsPathProperties (DefaultExtensionsPath);
 			evaluatedProperties.AddProperty (new BuildProperty ("MSBuildProjectDefaultTargets", DefaultTargets, PropertyType.Reserved));
 			evaluatedProperties.AddProperty (new BuildProperty ("OS", OS, PropertyType.Environment));
-
+#if NET_4_5	
+			// see http://msdn.microsoft.com/en-us/library/vstudio/hh162058(v=vs.120).aspx
+			if (effective_tools_version == "12.0") {
+				evaluatedProperties.AddProperty (new BuildProperty ("MSBuildToolsPath32", toolsPath, PropertyType.Reserved));
+				string frameworkToolsPath = parentEngine.Toolsets [effective_tools_version].FrameworkToolsPath;
+				if (frameworkToolsPath == null)
+					throw new Exception (String.Format ("Invalid tools version '{0}', no framework tools path set for this.", effective_tools_version));				
+				evaluatedProperties.AddProperty (new BuildProperty ("MSBuildFrameworkToolsPath", frameworkToolsPath, PropertyType.Reserved));
+				evaluatedProperties.AddProperty (new BuildProperty ("MSBuildFrameworkToolsPath32", frameworkToolsPath, PropertyType.Reserved));
+			}
+#endif
 			// FIXME: make some internal method that will work like GetDirectoryName but output String.Empty on null/String.Empty
 			string projectDir;
 			if (FullFileName == String.Empty)

mcs/class/Microsoft.Build.Engine/Microsoft.Build.BuildEngine/Toolset.cs

@@ -31,21 +31,28 @@ namespace Microsoft.Build.BuildEngine
 {
 	public class Toolset
 	{
-		public Toolset (string toolsVersion, string toolsPath, BuildPropertyGroup buildProperties)
+		public Toolset (string toolsVersion, string toolsPath, string toolsFrameworkPath, BuildPropertyGroup buildProperties)
 		{
 			ToolsVersion = toolsVersion;
 			ToolsPath = toolsPath;
+			FrameworkToolsPath = toolsFrameworkPath;
 			BuildProperties = buildProperties;
 		}
-
-		public Toolset (string toolsVersion, string toolsPath)
-			: this (toolsVersion, toolsPath, null)
+
+		public Toolset (string toolsVersion, string toolsPath, string toolsFrameworkPath)
+			: this (toolsVersion, toolsPath, toolsFrameworkPath, null)
+		{
+		}
+
+		public Toolset(string toolsVersion, string toolsPath)
+			: this (toolsVersion, toolsPath, toolsPath)
 		{
 		}
 
 		public BuildPropertyGroup BuildProperties { get; private set; }
 
 		public string ToolsVersion { get; private set; }
 		public string ToolsPath { get; private set; }
+		public string FrameworkToolsPath { get; private set; }		
 	}
 }

mcs/class/Microsoft.Build.Utilities/Microsoft.Build.Utilities/ToolLocationHelper.cs

@@ -48,6 +48,7 @@ static ToolLocationHelper ()
 			t2 = t1.Parent;
 
 			lib_mono_dir = t2.FullName;
+			var windowsPath = Environment.GetFolderPath (Environment.SpecialFolder.Windows);
 			if (Environment.GetEnvironmentVariable ("TESTING_MONO") != null) {
 				mono_dir = new string [] {
 					Path.Combine (lib_mono_dir, "net_1_0"),
@@ -57,6 +58,16 @@ static ToolLocationHelper ()
 					Path.Combine (lib_mono_dir, "net_4_0"),
 					Path.Combine (lib_mono_dir, "net_4_5")
 				};	
+			} else if (!string.IsNullOrEmpty (windowsPath) && lib_mono_dir.StartsWith (windowsPath)) {
+				//running in .NET, not Mono
+				mono_dir = new string [] {
+					Path.Combine (lib_mono_dir, "v1.0.3705"),
+					Path.Combine (lib_mono_dir, "v2.0.50727"),
+					Path.Combine (lib_mono_dir, "v2.0.50727"),
+					Path.Combine (lib_mono_dir, "v3.5"),
+					Path.Combine (lib_mono_dir, "v4.0.30319"),
+					Path.Combine (lib_mono_dir, "v4.0.30319")
+				};
 			} else {
 				mono_dir = new string [] {
 					Path.Combine (lib_mono_dir, "1.0"),
@@ -93,6 +104,13 @@ public static string GetPathToDotNetFramework (TargetDotNetFrameworkVersion vers
 			return mono_dir [(int)version];
 		}
 
+		public static string GetMSBuildInstallPath (string version)
+		{
+			//see http://msdn.microsoft.com/en-us/library/vstudio/bb397428(v=vs.120).aspx
+			var programFiles = Environment.GetFolderPath (Environment.SpecialFolder.ProgramFilesX86);
+			return Path.Combine (programFiles, "MSBuild", version, "bin");
+		}
+
 		[MonoTODO]
 		public static string GetPathToDotNetFrameworkFile (string fileName,
 								  TargetDotNetFrameworkVersion version)