gstreamer/generator/VirtualMethod.cs
2009-09-11 10:14:42 +02:00

156 lines
4.7 KiB
C#

// GtkSharp.Generation.VirtualMethod.cs - The VirtualMethod Generatable.
//
// Author: Mike Kestner <mkestner@novell.com>
//
// Copyright (c) 2003-2004 Novell, Inc.
// Copyright (c) 2009 Christian Hoff
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of version 2 of the GNU General Public
// License as published by the Free Software Foundation.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public
// License along with this program; if not, write to the
// Free Software Foundation, Inc., 59 Temple Place - Suite 330,
// Boston, MA 02111-1307, USA.
namespace GtkSharp.Generation {
using System;
using System.Collections;
using System.IO;
using System.Xml;
public abstract class VirtualMethod : MethodBase {
protected ReturnValue retval;
protected ManagedCallString call;
protected string modifiers = "";
public VirtualMethod (XmlElement elem, ObjectBase container_type) : base (elem, container_type)
{
if (container_type.ParserVersion == 1) {
// The old pre 2.14 parser didn't drop the 1st parameter in all <signal> and <virtual_method> elements
parms = new Parameters (elem ["parameters"], true);
}
retval = new ReturnValue (elem ["return-type"]);
}
protected abstract string CallString {
get;
}
VMSignature signature;
protected new VMSignature Signature {
get {
if (signature == null)
signature = new VMSignature (parms);
return signature;
}
}
/* Creates a callback method which invokes the corresponding virtual method
* @implementor is the class that implements the virtual method(e.g. the class that derives from an interface) or NULL if containing and declaring type are equal
*/
public void GenerateCallback (StreamWriter sw, ClassBase implementor)
{
if (!Validate ())
return;
string native_signature = "";
if (!IsStatic) {
native_signature += "IntPtr inst";
if (parms.Count > 0)
native_signature += ", ";
}
if (parms.Count > 0)
native_signature += parms.ImportSignature;
sw.WriteLine ("\t\t[UnmanagedFunctionPointer (CallingConvention.Cdecl)]");
sw.WriteLine ("\t\tdelegate {0} {1}NativeDelegate ({2});", retval.ToNativeType, this.Name, native_signature);
sw.WriteLine ();
sw.WriteLine ("\t\tstatic {0} {1}_cb ({2})", retval.ToNativeType, this.Name, native_signature);
sw.WriteLine ("\t\t{");
string unconditional = call.Unconditional ("\t\t\t");
if (unconditional.Length > 0)
sw.WriteLine (unconditional);
sw.WriteLine ("\t\t\ttry {");
if (!this.IsStatic) {
string type;
if (implementor != null)
type = implementor.QualifiedName;
else if (this.container_type is InterfaceGen)
type = this.container_type.Name + "Implementor"; // We are in an interface/adaptor, invoke the method in the implementor class
else
type = this.container_type.Name;
sw.WriteLine ("\t\t\t\t{0} __obj = Gst.GLib.Object.GetObject (inst, false) as {0};", type);
}
sw.Write (call.Setup ("\t\t\t\t"));
sw.Write ("\t\t\t\t");
if (!retval.IsVoid)
sw.Write (retval.CSType + " __result = ");
if (!this.IsStatic)
sw.Write ("__obj.");
sw.WriteLine (this.CallString + ";");
sw.Write (call.Finish ("\t\t\t\t"));
if (!retval.IsVoid)
sw.WriteLine ("\t\t\t\treturn " + retval.ToNative ("__result") + ";");
bool fatal = parms.HasOutParam || !retval.IsVoid;
sw.WriteLine ("\t\t\t} catch (Exception e) {");
sw.WriteLine ("\t\t\t\tGst.GLib.ExceptionManager.RaiseUnhandledException (e, " + (fatal ? "true" : "false") + ");");
if (fatal) {
sw.WriteLine ("\t\t\t\t// NOTREACHED: above call does not return.");
sw.WriteLine ("\t\t\t\tthrow e;");
}
sw.WriteLine ("\t\t\t}");
sw.WriteLine ("\t\t}");
sw.WriteLine ();
}
public bool IsValid {
get {
return Validate ();
}
}
enum ValidState {
Unvalidated,
Invalid,
Valid
}
ValidState vstate = ValidState.Unvalidated;
public override bool Validate ()
{
if (vstate != ValidState.Unvalidated)
return vstate == ValidState.Valid;
vstate = ValidState.Valid;
if (!parms.Validate () || !retval.Validate ()) {
vstate = ValidState.Invalid;
}
if (vstate == ValidState.Invalid) {
Console.WriteLine ("(in virtual method " + container_type.QualifiedName + "." + Name + ")");
return false;
} else {
// The call string has to be created *after* the params have been validated since the Parameters class contains no elements before validation
call = new ManagedCallString (parms);
return true;
}
}
}
}