Custom Signal Handler for Element.cs

git-svn-id: svn://anonsvn.mono-project.com/source/branches/abock/gstreamer-sharp@61891 e3ebcda4-bce8-0310-ba0a-eca2169e7518

ChangeLog

@@ -1,9 +1,24 @@
+2006-06-21  Khaled Mohammed <khaled.mohammed@gmail.com>
+
+	* gstreamer-sharp/DynamicSignalHandlerGenerator.cs: This class is 
+	reponsible for generating a custom delegate class which supports 
+	variable number of parameters.
+
+	* gstreamer-sharp/DyanmicSignalMarshalHandler.cs: This is an abstract
+	class and is derived by the new type generated by the Generator.
+	This class makes it easy for me to work with the new type.
+
+	* gstreamer-sharp/Element.custom: Added functions to add a custom signal,
+	a function which marshall's the signal parameters.
+
+	* sample/HelloWorld.cs: Added a sample to show the usuage of a custom signal.
+
 2006-06-04  Khaled Mohammed <khaled.mohammed@gmail.com>
 
-	* gstreamer/glue/Bin.c: added this file to the source. It has only one 
+	* gstreamer-sharp/glue/Bin.c: added this file to the source. It has only one 
 	function which gives offset of *children in the C struct.
 
-	* gstreamer/glue/Makefile.am: added Bin.c to the list of C source that
+	* gstreamer-sharp/glue/Makefile.am: added Bin.c to the list of C source that
 	must be compiled.
 
 	* tests/ElementTest.cs: added NUnit tests for Element class.

gstreamer-sharp/Bin.custom

@@ -23,6 +23,17 @@
         }
     }
 
+    [DllImport("gstreamer-0.10.dll")]
+    static extern bool gst_bin_add(IntPtr raw, IntPtr element);
+
+    public bool Add(Gst.Element element) {
+//	if(element !=null)
+//		element.Refcount++;
+	bool raw_ret = gst_bin_add(Handle, element == null ? IntPtr.Zero : element.Handle);
+	bool ret = raw_ret;
+	return ret;
+    }
+
     public bool AddMany(params Element[] elements)
     {
         if(elements == null) {
@@ -37,3 +48,6 @@
         
         return true;
     }
+
+
+   

gstreamer-sharp/DynamicSignalHandlerGenerator.cs

@@ -0,0 +1,112 @@
+//
+// Authors
+//    Khaled Mohammed < Khaled.Mohammed@gmail.com >
+//
+// (C) 2006 Novell
+//
+
+using System;
+using System.Reflection;
+using System.Reflection.Emit;
+using System.Runtime.InteropServices;
+
+namespace Gst {
+
+public class DynamicSignalHandlerGenerator {
+
+	Type _NewType;
+
+	public Type NewType {
+		get { return _NewType; }
+		set { _NewType = value; }
+	}
+
+	public DynamicSignalHandlerGenerator(Type [] eventParams, string ASSEMBLY_NAME, string classname) {
+
+		// Define the parameters of marshall handler
+		Type [] paramTypes = new Type[eventParams.Length + 1];
+		for(int i=0; i < paramTypes.Length; i++)
+			paramTypes[i] = typeof(IntPtr);
+
+
+		Type [] paramBeginInvokeTypes = new Type[eventParams.Length + 2];
+		for(int i=0; i < paramBeginInvokeTypes.Length - 2 ; i++) 
+			paramBeginInvokeTypes[i] = typeof(IntPtr);
+
+		paramBeginInvokeTypes[paramBeginInvokeTypes.Length - 2] = typeof(System.AsyncCallback);
+		paramBeginInvokeTypes[paramBeginInvokeTypes.Length - 1] = typeof(object);
+	
+		
+		// defining the assembly
+		AssemblyName dynamic_assembly_name = new AssemblyName();
+		dynamic_assembly_name.Name = ASSEMBLY_NAME;
+
+		AssemblyBuilder dynamic_assembly = AppDomain.CurrentDomain.DefineDynamicAssembly(
+			dynamic_assembly_name, AssemblyBuilderAccess.RunAndSave);
+
+		// create the dll file in the memory
+		ModuleBuilder dynamic_module = dynamic_assembly.DefineDynamicModule(ASSEMBLY_NAME, ASSEMBLY_NAME + ".dll");
+
+		TypeBuilder dynamic_class = dynamic_module.DefineType(ASSEMBLY_NAME + "." + classname, TypeAttributes.Public, typeof(Gst.DynamicSignalMarshalHandler));
+
+		MethodBuilder method_CSCB = dynamic_class.DefineMethod("CustomSignalCallback", MethodAttributes.Public | MethodAttributes.HideBySig, typeof(void), paramTypes );
+	
+		ILGenerator method_IL = method_CSCB.GetILGenerator();
+		method_IL.Emit(OpCodes.Ldc_I4, paramTypes.Length);
+		method_IL.Emit(OpCodes.Newarr, typeof(IntPtr));
+
+		for(int i=0; i < paramTypes.Length; i++) {
+			method_IL.Emit(OpCodes.Dup);
+			method_IL.Emit(OpCodes.Ldc_I4, i);
+			method_IL.Emit(OpCodes.Ldelema, typeof(IntPtr));
+			method_IL.Emit(OpCodes.Ldarg, i+1);
+			method_IL.Emit(OpCodes.Stobj, typeof(IntPtr));
+		}
+		
+		method_IL.Emit(OpCodes.Call, typeof(Gst.Element).GetMethod("CustomMarshaller"));	
+		method_IL.Emit(OpCodes.Ret);
+
+
+		// define delegate
+		TypeBuilder tbDelegate = dynamic_class.DefineNestedType("CustomSignalDelegate", TypeAttributes.NestedPublic | TypeAttributes.Sealed, typeof(MulticastDelegate), null);
+
+	
+		// CustomSignalDelegate()
+		ConstructorBuilder constructor = tbDelegate.DefineConstructor(MethodAttributes.Public | MethodAttributes.RTSpecialName | MethodAttributes.SpecialName | MethodAttributes.HideBySig, CallingConventions.Standard, new Type [] { typeof(object), typeof(IntPtr) });
+		constructor.SetImplementationFlags (MethodImplAttributes.Runtime);
+		//constructor_IL = constructor.GetILGenerator();
+		//constructor_IL.Emit(OpCodes.Ret);
+
+		MethodBuilder method = tbDelegate.DefineMethod("Invoke", MethodAttributes.Public | MethodAttributes.Virtual | MethodAttributes.HideBySig , typeof(void), paramTypes);
+		method.SetImplementationFlags (MethodImplAttributes.Runtime);
+
+		//   .method public virtual  hidebysig  newslot 
+		//    instance default class [mscorlib]System.IAsyncResult BeginInvoke (native int arg0, native int arg1, native int gch, 			// class [mscorlib]System.AsyncCallback callback, object 'object')  runtime managed 
+		method = tbDelegate.DefineMethod("BeginInvoke", MethodAttributes.Public | MethodAttributes.Virtual | MethodAttributes.HideBySig | MethodAttributes.NewSlot, typeof(System.IAsyncResult), paramBeginInvokeTypes);
+		method.SetImplementationFlags(MethodImplAttributes.Runtime); 
+
+	
+		// .method public virtual  hidebysig  newslot 
+	        //   instance default void EndInvoke (class [mscorlib]System.IAsyncResult result)  runtime managed 
+		method = tbDelegate.DefineMethod("EndInvoke", MethodAttributes.Public | MethodAttributes.HideBySig | MethodAttributes.NewSlot | MethodAttributes.Virtual, typeof(void), new Type [] { typeof(System.IAsyncResult) });
+		method.SetImplementationFlags(MethodImplAttributes.Runtime); 
+
+		//  .method public virtual  hidebysig 
+	        //   instance default class [mscorlib]System.Delegate Func ()  cil managed 
+		method = dynamic_class.DefineMethod("Func",  MethodAttributes.Public | MethodAttributes.Virtual | MethodAttributes.HideBySig , typeof(Delegate), null);
+
+		method_IL = method.GetILGenerator();
+
+
+		method_IL.Emit(OpCodes.Ldarg_0);
+		method_IL.Emit(OpCodes.Ldftn, method_CSCB);
+		method_IL.Emit(OpCodes.Newobj, constructor);
+		method_IL.Emit(OpCodes.Ret);
+
+		_NewType = dynamic_class.CreateType();
+
+		dynamic_assembly.Save(ASSEMBLY_NAME + ".dll");
+
+	}
+}
+}

gstreamer-sharp/DynamicSignalMarshalHandler.cs

@@ -0,0 +1,14 @@
+//
+// Authors
+//   Khaled Mohammed < Khaled.Mohammed@gmail.com >
+//
+// (C) 2006 Novell
+//
+
+using System;
+
+namespace Gst {
+	public abstract class DynamicSignalMarshalHandler {
+		public abstract Delegate Func();
+	}
+}

gstreamer-sharp/Element.custom

@@ -42,3 +42,43 @@
     {
         return gst_element_query_duration(Handle, ref format, out duration);
     }
+
+	static Type [] paramTypes;
+
+    public void AddCustomEvent(string name, Delegate onCustom ) {
+	System.Reflection.ParameterInfo [] pi = onCustom.Method.GetParameters();
+
+	paramTypes = new Type[pi.Length];
+	for(int i=0; i < paramTypes.Length; i++) {
+		paramTypes[i] = pi[i].ParameterType;
+	}
+
+	string DYNAMIC_ASSEMBLY = "Gst.DynamicSignals.Element." + Name + "." + name;
+	string DYNAMIC_CLASS = "NewDSMH";
+
+	DynamicSignalHandlerGenerator dshGenerator = new DynamicSignalHandlerGenerator(paramTypes, DYNAMIC_ASSEMBLY, DYNAMIC_CLASS);
+	Type NewType = System.Reflection.Assembly.LoadFile(DYNAMIC_ASSEMBLY +  ".dll").GetType(DYNAMIC_ASSEMBLY + "." + DYNAMIC_CLASS);
+
+	DynamicSignalMarshalHandler dsmh = Activator.CreateInstance(NewType) as DynamicSignalMarshalHandler;
+
+	GLib.Signal sig = GLib.Signal.Lookup (this, name, dsmh.Func());
+	
+	sig.AddDelegate(onCustom);
+    }
+
+	public static void CustomMarshaller(params IntPtr [] args) {
+		GLib.Signal sig = ((GCHandle) args[args.Length - 1]).Target as GLib.Signal;
+		object [] newargs = new object[args.Length - 1];
+		for(int i=0; i < newargs.Length; i++) {
+			if(paramTypes[i].IsSubclassOf(typeof(GLib.Object))) {
+				newargs[i] = GLib.Object.GetObject(args[i]);
+			}
+			else if(paramTypes[i].IsSubclassOf(typeof(GLib.Opaque))) {
+				newargs[i] = GLib.Opaque.GetOpaque(args[i], paramTypes[i], true);
+			}
+		}
+
+		Delegate d = sig.Handler as Delegate;
+		d.DynamicInvoke(newargs);	
+	}
+

gstreamer-sharp/Gstreamer.metadata

@@ -6,6 +6,8 @@
 
   <attr path="/api/namespace/object[@name='Bin']/field[@name='Children']" name="hidden">1</attr>
 
+  <attr path="/api/namespace/object[@name='Bin']/method[@name='Add']" name="hidden">1</attr> 
+
 
   <attr path="/api/namespace/object[@name='Element']/signal[@name='NoMorePads']" name="name">HasNoMorePads</attr>
   <!-- Hidden as the parameter name conflicts with generated code -->

gstreamer-sharp/Makefile.am

@@ -41,6 +41,8 @@ sources = \
 	Version.cs \
 	AssemblyInfo.cs \
 	CommonTags.cs \
+	DynamicSignalMarshalHandler.cs \
+	DynamicSignalHandlerGenerator.cs \
 	plugins-base/PlayBin.cs \
 	plugins-base/DecodeBin.cs
 

sample/Makefile.am

@@ -1,4 +1,4 @@
-TARGETS = playbin-player.exe decodebin-transcoder.exe
+TARGETS = playbin-player.exe decodebin-transcoder.exe helloworld.exe
 DEBUGS = $(addsuffix .mdb, $(TARGETS))
 
 assemblies=$(top_builddir)/gstreamer-sharp/gstreamer-sharp.dll
@@ -11,6 +11,9 @@ playbin-player.exe: $(srcdir)/PlayBinPlayer.cs $(assemblies)
 decodebin-transcoder.exe: $(srcdir)/DecodeBinTranscoder.cs $(assemblies)
 	$(CSC) -out:$@ $(GLIBSHARP_LIBS) $(references) $(srcdir)/DecodeBinTranscoder.cs 
 
+helloworld.exe: $(srcdir)/HelloWorld.cs $(assemblies)
+	$(CSC) -out:$@ $(GLIBSHARP_LIBS) $(references) $(srcdir)/HelloWorld.cs
+
 noinst_SCRIPTS = $(TARGETS)
 
 CLEANFILES = $(TARGETS) $(DEBUGS)
@@ -18,4 +21,5 @@ MAINTAINERCLEANFILES = Makefile.in
 
 EXTRA_DIST = \
 	PlayBinPlayer.cs \
-	DecodeBinTranscoder.cs
+	DecodeBinTranscoder.cs \
+	HelloWorld.cs