ref: 44cb6fe8162588851dbb8a23e69a88b85e92fb56
dir: /src/base/ftobject.c/
#include "ftobject.c"
#define FT_MAGIC_DEATH 0xDEADdead
#define FT_MAGIC_CLASS 0x12345678
#define FT_OBJECT_CHECK(o) \
( FT_OBJECT(o) != NULL && \
FT_OBJECT(o)->clazz != NULL && \
FT_OBJECT(o)->ref_count >= 1 && \
FT_OBJECT(o)->clazz->magic == FT_MAGIC_CLASS )
/*******************************************************************/
/*******************************************************************/
/***** *****/
/***** *****/
/***** M E T A - C L A S S *****/
/***** *****/
/***** *****/
/*******************************************************************/
/*******************************************************************/
/* we use a dynamic hash table to map types to classes */
/* this structure defines the layout of each node of */
/* this table */
typedef struct FT_ClassHNodeRec_
{
FT_HashNodeRec hnode;
FT_Type ctype;
FT_Class clazz;
} FT_ClassHNodeRec, *FT_ClassHNode;
/* the meta class contains a type -> class mapping */
/* and owns all class objects.. */
/* */
typedef struct FT_MetaClassRec_
{
FT_ClassRec clazz;
FT_HashRec type_to_class;
} FT_MetaClassRec, *FT_MetaClass;
/* forward declaration */
static const FT_TypeRec ft_meta_class_type;
/* destroy a given class */
static void
ft_class_hnode_destroy( FT_ClassHNode node )
{
FT_Clazz clazz = node->clazz;
FT_Memory memory = clazz->memory;
FT_Type ctype = clazz->type;
if ( ctype->class_done )
ctype->class_done( clazz );
FT_FREE( clazz );
node->clazz = NULL;
node->type = NULL;
FT_FREE( node );
}
static FT_Int
ft_class_hnode_compare( const FT_ClassHNode node1,
const FT_ClassHNode node2 )
{
return ( node1->type == node2->type );
}
static void
ft_metaclass_done( FT_MetaClass meta )
{
/* clear all objects */
ft_hash_done( &meta->type_to_class,
(FT_Hash_ForeachFunc) ft_class_destroy,
NULL );
meta->clazz->object.clazz = NULL;
meta->clazz->object.ref_count = 0;
meta->clazz->magic = FT_MAGIC_DEATH;
}
static void
ft_metaclass_init( FT_MetaClass meta,
FT_Library library )
{
FT_ClassRec* clazz = meta->clazz;
/* the meta-class is its OWN class !! */
clazz->object.clazz = (FT_Class) clazz;
clazz->object.ref_count = 1;
clazz->magic = FT_MAGIC_CLASS;
clazz->library = library;
clazz->memory = library->memory;
clazz->type = &ft_metaclass_type;
clazz->info = NULL;
clazz->obj_size = sizeof( FT_ClassRec );
clazz->obj_init = NULL;
clazz->obj_done = NULL;
ft_hash_init( &meta->type_to_class,
(FT_Hash_CompareFunc) ft_class_hnode_compare,
library->memory );
}
/* find or create the class corresponding to a given type */
static FT_Class
ft_metaclass_get_class( FT_MetaClass meta,
FT_Type ctype )
{
FT_ClassHNodeRec keynode, *node, **pnode;
FT_Memory memory;
keynode.hnode.hash = (FT_UInt32)( ctype >> 2 );
keynode.type = type;
pnode = (FT_ClassHNode) ft_hash_lookup( &meta->type_to_class,
&noderec );
node = *pnode;
if ( node != NULL )
return node->clazz;
memory = FT_CLASS__MEMORY(meta);
node = FT_MEM_SAFE_ALLOC( sizeof(*node) );
if ( node != NULL )
{
FT_ClassRec* clazz;
clazz = FT_MEM_SAFE_ALLOC( ctype->class_size );
if ( clazz == NULL )
{
FT_FREE( node );
FT_XTHROW( FT_Err_Out_Of_Memory );
}
}
}
static const FT_TypeRec ft_meta_class_type =
{
"FT2.MetaClass",
NULL,
sizeof( FT_MetaClassRec ),
(FT_Object_InitFunc) ft_metaclass_init,
(FT_Object_DoneFunc) ft_metaclass_done,
sizeof( FT_ClassRec ),
(FT_Object_InitFunc) ft_class_init,
(FT_Object_DoneFunc) ft_class_done
};
FT_BASE_DEF( FT_Int )
ft_object_check( FT_Pointer obj )
{
return FT_OBJECT_CHECK(obj);
}
FT_BASE_DEF( FT_Int )
ft_object_is_a( FT_Pointer obj,
FT_Class clazz )
{
if ( FT_OBJECT_CHECK(obj) )
{
FT_Object o = FT_OBJECT(obj);
FT_Class c = FT_OBJECT__CLASS(obj);
do
{
if ( c == clazz )
return 1;
c = c->super;
}
while ( c == NULL );
return (clazz == NULL);
}
}
/* the cleanup routine for all objects */
static void
ft_object_cleanup( FT_Object object )
{
FT_Memory memory = FT_OBJECT__MEMORY(object);
FT_Class clazz = FT_OBJECT__CLASS(object);
if ( clazz->obj_done )
clazz->obj_done( object );
FT_FREE( object );
}
FT_BASE_DEF( FT_Object )
ft_object_new( FT_Class clazz,
FT_Pointer init_data )
{
FT_Memory memory;
FT_Object obj;
FT_ASSERT_IS_CLASS(clazz);
memory = FT_CLASS__MEMORY(clazz);
obj = ft_mem_alloc( clazz->obj_size, memory );
obj->clazz = clazz;
obj->ref_count = 1;
if ( clazz->obj_init )
{
FT_CleanupStack stack = FT_MEMORY__CLEANUP(memory);
ft_cleanup_push( stack, obj, (FT_CleanupFunc) ft_object_cleanup, NULL );
clazz->obj_init( obj, init_data );
ft_cleanup_pop( stack, obj, 0 );
}
return obj;
}
FT_BASE_DEF( void )
ft_object_create( FT_Object *pobject,
FT_Class clazz,
FT_Pointer init_data )
{
FT_Memory memory;
FT_Object obj;
FT_ASSERT_IS_CLASS(clazz);
memory = FT_CLASS__MEMORY(memory);
obj = ft_mem_alloc( clazz->obj_size, memory );
obj->clazz = clazz;
obj->ref_count = 1;
*pobject = obj;
if ( clazz->obj_init )
clazz->obj_init( obj, init_data );
}
FT_BASE_DEF( FT_Class )
ft_class_find_by_type( FT_Type type,
FT_Memory memory )
{
}
FT_BASE_DEF( FT_Class )
ft_class_find_by_name( FT_CString class_name,
FT_Memory memory );
FT_BASE_DEF( FT_Object )
ft_object_new_from_type( FT_Type type,
FT_Pointer data,
FT_Memory memory );
FT_BASE_DEF( void )
ft_object_create_from_type( FT_Object *pobject,
FT_Type type,
FT_Pointer init_data,
FT_Memory memory );
FT_BASE_DEF( void )
ft_object_push( FT_Object object );
FT_BASE_DEF( void )
ft_object_pop( FT_Object object );
FT_BASE_DEF( void )
ft_object_pop_destroy( FT_Object object );