ref: b466a7650ce97d3843bcbb4b145bda323a201022
dir: /src/cache/ftlru.c/
#include <cache/ftlru.h>
#include <freetype/internal/ftobjs.h>
#include <freetype/internal/ftlist.h>
static
void lru_build_free_list( FT_LruNode nodes,
FT_UInt count,
FT_List free_list )
{
FT_LruNode node = nodes;
FT_LruNode limit = node + count;
free_list->head = free_list->tail = 0;
for ( ; node < limit; node++ )
FT_List_Add( free_list, (FT_ListNode)node );
}
FT_EXPORT_FUNC(FT_Error) FT_Lru_New ( const FT_Lru_Class* clazz,
FT_UInt max_elements,
FT_Memory memory,
FT_Bool pre_alloc,
FT_Lru *alru )
{
FT_Error error;
FT_Lru lru;
*alru = 0;
if ( !ALLOC( lru, sizeof(*lru) ) )
{
if (pre_alloc)
{
/* allocate static array of lru list nodes */
if ( ALLOC_ARRAY( lru->nodes, max_elements, FT_LruNodeRec ) )
{
FREE( lru );
goto Exit;
}
/* build the 'free_nodes' list from the array */
lru_build_free_list( lru->nodes, max_elements, &lru->free_nodes );
}
/* initialize common fields */
lru->clazz = (FT_Lru_Class*)clazz;
lru->max_elements = max_elements;
lru->memory = memory;
*alru = lru;
}
Exit:
return error;
}
FT_EXPORT_DEF(void) FT_Lru_Reset ( FT_Lru lru )
{
FT_ListNode node = lru->elements.head;
FT_Lru_Class* clazz = lru->clazz;
FT_Memory memory = lru->memory;
while (node)
{
FT_ListNode next = node->next;
clazz->done_element( lru, (FT_LruNode)node );
if (!lru->nodes)
FREE(node);
node = next;
}
/* rebuild free list if necessary */
if (lru->nodes)
lru_build_free_list( lru->nodes, lru->max_elements, &lru->free_nodes );
lru->elements.head = lru->elements.tail = 0;
lru->num_elements = 0;
}
FT_EXPORT_DEF(void) FT_Lru_Done ( FT_Lru lru )
{
FT_Memory memory = lru->memory;
FT_Lru_Reset(lru);
FREE(lru);
}
FT_EXPORT_DEF(FT_Error) FT_Lru_Lookup_Node( FT_Lru lru,
FT_LruKey key,
FT_LruNode* anode )
{
FT_Error error = 0;
FT_ListNode node = lru->elements.head;
FT_Lru_Class* clazz = lru->clazz;
FT_LruNode found = 0;
FT_Memory memory = lru->memory;
if (clazz->compare_element)
{
for ( ; node; node = node->next )
if (clazz->compare_element( (FT_LruNode)node, key ))
{
found = (FT_LruNode)node;
break;
}
}
else
{
for ( ; node; node = node->next )
if (((FT_LruNode)node)->key == key)
{
found = (FT_LruNode)node;
break;
}
}
if (!found)
{
/* we didn't find the relevant element. We will now try */
/* to create a new one.. */
if ( lru->num_elements >= lru->max_elements )
{
/* this lru list is full, we will now flush */
/* the oldest node */
FT_LruNode lru_node;
node = lru->elements.tail;
lru_node = (FT_LruNode)node;
if (clazz->flush_element)
error = clazz->flush_element( lru, lru_node, key );
else
{
clazz->done_element( lru, lru_node );
lru_node->key = key;
node->data = 0;
error = clazz->init_element( lru, lru_node );
}
if (!error)
{
/* now, move element to top of list */
FT_List_Up( &lru->elements, node );
}
else
{
/* in case of error, the node must be discarded */
FT_List_Remove( &lru->elements, node );
lru->num_elements--;
if (lru->nodes)
FT_List_Insert( &lru->free_nodes, node );
else
FREE( lru_node );
}
}
else
{
FT_LruNode lru_node;
/* create a new lru list node, then the element for it */
if (lru->nodes)
{
node = lru->free_nodes.head;
lru_node = (FT_LruNode)node;
lru_node->key = key;
error = clazz->init_element( lru, lru_node );
if (error)
goto Exit;
FT_List_Remove( &lru->free_nodes, node );
}
else
{
if ( ALLOC( lru_node, sizeof(*lru_node) ) )
goto Exit;
lru_node->key = key;
error = clazz->init_element( lru, lru_node );
if (error)
{
FREE( lru_node );
goto Exit;
}
}
found = lru_node;
node = (FT_ListNode)lru_node;
FT_List_Insert( &lru->elements, node );
lru->num_elements++;
}
}
Exit:
*anode = found;
return error;
}
FT_EXPORT_DEF(FT_Error) FT_Lru_Lookup( FT_Lru lru,
FT_LruKey key,
FT_Pointer *aobject )
{
FT_Error error;
FT_LruNode node;
*aobject = 0;
error = FT_Lru_Lookup_Node( lru, key, &node );
if (!error)
*aobject = node->root.data;
return error;
}
FT_EXPORT_FUNC(void) FT_Lru_Remove_Node( FT_Lru lru,
FT_LruNode node )
{
if (lru->num_elements > 0)
{
FT_List_Remove( &lru->elements, (FT_ListNode)node );
lru->clazz->done_element( lru, node );
if (lru->nodes)
FT_List_Insert( &lru->free_nodes, (FT_ListNode)node );
else
{
FT_Memory memory = lru->memory;
FREE(node);
}
lru->num_elements--;
}
}
FT_EXPORT_FUNC(void) FT_Lru_Remove_Selection( FT_Lru lru,
FT_Lru_Selector selector,
FT_Pointer data )
{
if (lru->num_elements > 0)
{
FT_ListNode node = lru->elements.head;
FT_ListNode next;
while (node)
{
next = node->next;
if ( selector( lru, (FT_LruNode)node, data ) )
{
/* remove this element from the list, and destroy it */
FT_Lru_Remove_Node( lru, (FT_LruNode)node );
}
node = next;
}
}
}