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