Xcode: Add option to specify build system variant

Extend the `-T <toolset>` option to support a `buildsystem=` field with
the Xcode generator.  Add a `CMAKE_XCODE_BUILD_SYSTEM` variable to
inform project code about the selected build system variant.

1 files changed, 11 insertions, 0 deletions

diff --git a/Source/cmGlobalXCodeGenerator.h b/Source/cmGlobalXCodeGenerator.h
index 4e686822ba..bbf3ee915c 100644
--- a/Source/cmGlobalXCodeGenerator.h
+++ b/Source/cmGlobalXCodeGenerator.h
@@ -113,11 +113,20 @@ public:
                            cmMakefile* mf) override;
   void AppendFlag(std::string& flags, std::string const& flag) const;
 
+  enum class BuildSystem
+  {
+    One = 1,
+  };
+
 protected:
   void AddExtraIDETargets() override;
   void Generate() override;
 
 private:
+  bool ParseGeneratorToolset(std::string const& ts, cmMakefile* mf);
+  bool ProcessGeneratorToolsetField(std::string const& key,
+                                    std::string const& value, cmMakefile* mf);
+
   cmXCodeObject* CreateOrGetPBXGroup(cmGeneratorTarget* gtgt,
                                      cmSourceGroup* sg);
   cmXCodeObject* CreatePBXGroup(cmXCodeObject* parent,
@@ -254,6 +263,8 @@ protected:
   std::vector<std::unique_ptr<cmXCodeObject>> XCodeObjects;
   cmXCodeObject* RootObject;
 
+  BuildSystem XcodeBuildSystem = BuildSystem::One;
+
 private:
   std::string const& GetXcodeBuildCommand();
   std::string FindXcodeBuildCommand();