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Author: Dietmar Maurer (dietmar@ximian.com)
(C) 2001 Ximian, Inc.
Object and VTable layout
========================
The first pointer inside an Object points to a MonoVtable structure. Objects
also contains a MonoThreadsSync structure which is used by the mono Thread
implementation.
typedef struct {
MonoVTable *vtable;
MonoThreadsSync synchronisation;
/* object specific data goes here */
} MonoObject;
The MonoVtable contains the vtable, interface offsets and a pointer to static
class data. Each object/vtable belongs to exactly one AppDomain.
typedef struct {
MonoClass *klass;
MonoDomain *domain;
gpointer *interface_offsets;
/* a pointer to static data */
gpointer data;
/* the variable sized vtable is included at the end */
gpointer vtable [0];
} MonoVTable;
The MonoClass contains domain independent Class infos.
typedef struct {
/* various class infos */
MonoClass *parent;
const char *name;
const char *name_space;
...
} MonoClass;
Calling virtual functions:
==========================
Each MonoMethod (if virtual) has an associated slot, which is an index into the
VTable. So we can use the following code to compute the address of a virtual
function:
method_addr = object->vtable->vtable [method->slot];
Calling interface methods:
==========================
Each interface class is associated with an unique ID. The following code
computes the address of an interface function:
method_addr = *(object->vtable->interface_offsets [interface_id] + method->slot*4);
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