Merge pull request livecode#1764 from runrevmark/feature-lcb_module_context

runrevmark · runrevmark · commit 8b03a43fd3b9 · 2015-02-04T15:13:07.000Z
[[ LCB ]] Access to current LCB module ptr
diff --git a/libscript/include/script.h b/libscript/include/script.h
@@ -202,6 +202,9 @@ MCScriptModuleRef MCScriptRetainModule(MCScriptModuleRef module);
 // Release a module.
 void MCScriptReleaseModule(MCScriptModuleRef module);
 
+// Gets the module ptr for the most recent LCB stack frame on the current thread's stack.
+MCScriptModuleRef MCScriptGetCurrentModule(void);
+
 ////////////////////////////////////////////////////////////////////////////////
 
 // Create an instance of the given module. If the module is single-instance it
diff --git a/libscript/src/script-instance.cpp b/libscript/src/script-instance.cpp
@@ -46,6 +46,13 @@ void __MCScriptHandlerRelease(void *context);
 
 ////////////////////////////////////////////////////////////////////////////////
 
+// This is the module of the most recent LCB stack frame on the current thread's
+// stack. It is set before and after a foreign handler call so that the native
+// code can get some element of context.
+static MCScriptModuleRef s_current_module = nil;
+
+////////////////////////////////////////////////////////////////////////////////
+
 bool MCScriptCreateInstanceOfModule(MCScriptModuleRef p_module, MCScriptInstanceRef& r_instance)
 {
     bool t_success;
@@ -1604,7 +1611,16 @@ static bool MCScriptPerformInvoke(MCScriptFrame*& x_frame, byte_t*& x_next_bytec
 		MCScriptForeignHandlerDefinition *t_foreign_handler;
 		t_foreign_handler = MCScriptDefinitionAsForeignHandler(p_handler);
 		
-		return MCScriptPerformForeignInvoke(x_frame, p_instance, t_foreign_handler, p_arguments, p_arity);
+        MCScriptModuleRef t_previous_module;
+        t_previous_module = s_current_module;
+        s_current_module = x_frame -> instance -> module;
+        
+		bool t_success;
+        t_success = MCScriptPerformForeignInvoke(x_frame, p_instance, t_foreign_handler, p_arguments, p_arity);
+        
+        s_current_module = t_previous_module;
+        
+        return t_success;
 	}
 	
 	/* LOAD CHECK */ __MCScriptUnreachable__("non-handler definition passed to invoke");
@@ -2307,6 +2323,13 @@ bool MCScriptCallHandlerOfInstanceInternal(MCScriptInstanceRef self, MCScriptHan
 
 ////////////////////////////////////////////////////////////////////////////////
 
+MCScriptModuleRef MCScriptGetCurrentModule(void)
+{
+    return s_current_module;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
 MCHandlerCallbacks __kMCScriptHandlerCallbacks =
 {
     sizeof(__MCScriptHandlerContext),
