ref: b5349a9b75b233b4036da594187a9959c3446890
dir: /src/cache/ftccache.c/
/***************************************************************************/
/* */
/* ftccache.c */
/* */
/* The FreeType internal cache interface (body). */
/* */
/* Copyright 2000-2001 by */
/* David Turner, Robert Wilhelm, and Werner Lemberg. */
/* */
/* This file is part of the FreeType project, and may only be used, */
/* modified, and distributed under the terms of the FreeType project */
/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
/* this file you indicate that you have read the license and */
/* understand and accept it fully. */
/* */
/***************************************************************************/
#include <ft2build.h>
#include FT_CACHE_MANAGER_H
#include FT_INTERNAL_OBJECTS_H
#include FT_INTERNAL_DEBUG_H
#include "ftcerror.h"
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** CACHE NODE DEFINITIONS *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
FT_EXPORT_DEF( void )
ftc_node_done( FTC_Node node,
FTC_Cache cache )
{
FTC_Family family;
FTC_FamilyEntry entry;
entry = cache->manager->families.entries + node->fam_index;
family = entry->family;
/* remove from parent set table - eventually destroy the set */
if ( --family->num_nodes == 0 )
FT_LruList_Remove( cache->families, (FT_LruNode) family );
}
/* add a new node to the head of the manager's circular MRU list */
static void
ftc_node_mru_link( FTC_Node node,
FTC_Manager manager )
{
FTC_Node first = manager->nodes_list;
if ( first )
{
node->mru_prev = first->mru_prev;
node->mru_next = first;
first->mru_prev->mru_next = node;
first->mru_prev = node;
}
else
{
node->mru_next = node;
node->mru_prev = node;
}
manager->nodes_list = node;
manager->num_nodes++;
}
/* remove a node from the manager's MRU list */
static void
ftc_node_mru_unlink( FTC_Node node,
FTC_Manager manager )
{
FTC_Node prev = node->mru_prev;
FTC_Node next = node->mru_next;
FTC_Node first = manager->nodes_list;
prev->mru_next = next;
next->mru_prev = prev;
if ( node->mru_next == first )
{
/* this is the last node in the list; update its head pointer */
if ( node == first )
manager->nodes_list = NULL;
else
first->mru_prev = prev;
}
node->mru_next = NULL;
node->mru_prev = NULL;
manager->num_nodes--;
}
/* move a node to the head of the manager's MRU list */
static void
ftc_node_mru_up( FTC_Node node,
FTC_Manager manager )
{
FTC_Node first = manager->nodes_list;
if ( node != first )
{
ftc_node_mru_unlink( node, manager );
ftc_node_mru_link( node, manager );
}
}
/* remove a node from its cache's hash table */
static void
ftc_node_hash_unlink( FTC_Node node,
FTC_Cache cache )
{
FTC_Node *pnode = cache->buckets + ( node->hash % cache->size );
for (;;)
{
if ( *pnode == NULL )
{
FT_ERROR(( "FreeType.cache.hash_unlink: unknown node!\n" ));
return;
}
if ( *pnode == node )
{
*pnode = node->link;
node->link = NULL;
cache->nodes--;
return;
}
pnode = &(*pnode)->link;
}
}
/* add a node to the "top" of its cache's hash table */
static void
ftc_node_hash_link( FTC_Node node,
FTC_Cache cache )
{
FTC_Node *pnode = cache->buckets + ( node->hash % cache->size );
node->link = *pnode;
*pnode = node;
cache->nodes++;
}
/* remove a node from the cache manager */
FT_EXPORT_DEF( void )
ftc_node_destroy( FTC_Node node,
FTC_Manager manager )
{
FT_Memory memory = manager->library->memory;
FTC_Cache cache;
FTC_FamilyEntry entry;
FTC_Cache_Class clazz;
#ifdef FT_DEBUG_ERROR
/* find node's cache */
if ( node->fam_index >= manager->families.count )
{
FT_ERROR(( "ftc_node_destroy: invalid node handle\n" ));
return;
}
#endif
entry = manager->families.entries + node->fam_index;
cache = entry->cache;
#ifdef FT_DEBUG_ERROR
if ( cache == NULL )
{
FT_ERROR(( "ftc_node_destroy: invalid node handle\n" ));
return;
}
#endif
clazz = cache->clazz;
manager->cur_weight -= clazz->node_weight( node, cache );
/* remove node from mru list */
ftc_node_mru_unlink( node, manager );
/* remove node from cache's hash table */
ftc_node_hash_unlink( node, cache );
/* now finalize it */
if ( clazz->node_done )
clazz->node_done( node, cache );
FREE( node );
/* check, just in case of general corruption :-) */
if ( manager->num_nodes == 0 )
FT_ERROR(( "ftc_node_destroy: invalid cache node count! = %d\n",
manager->num_nodes ));
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** CACHE FAMILY DEFINITIONS *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
FT_EXPORT_DEF( FT_Error )
ftc_family_init( FTC_Family family,
FTC_Query query,
FTC_Cache cache )
{
FT_Error error;
FTC_Manager manager = cache->manager;
FT_Memory memory = manager->library->memory;
FTC_FamilyEntry entry;
family->cache = cache;
family->num_nodes = 0;
/* now add to manager's family table */
error = ftc_family_table_alloc( &manager->families, memory, &entry );
if ( !error )
{
entry->cache = cache;
entry->family = family;
family->fam_index = entry->index;
query->family = family; /* save family in query */
}
return error;
}
FT_EXPORT_DEF( void )
ftc_family_done( FTC_Family family )
{
FTC_Manager manager = family->cache->manager;
/* remove from manager's family table */
ftc_family_table_free( &manager->families, family->fam_index );
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** ABSTRACT CACHE CLASS *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
#define FTC_PRIMES_MIN 7
#define FTC_PRIMES_MAX 13845163
static const FT_UInt ftc_primes[] =
{
7,
11,
19,
37,
73,
109,
163,
251,
367,
557,
823,
1237,
1861,
2777,
4177,
6247,
9371,
14057,
21089,
31627,
47431,
71143,
106721,
160073,
240101,
360163,
540217,
810343,
1215497,
1823231,
2734867,
4102283,
6153409,
9230113,
13845163,
};
static FT_UFast
ftc_prime_closest( FT_UFast num )
{
FT_UInt i;
for ( i = 0; i < sizeof ( ftc_primes ) / sizeof ( ftc_primes[0] ); i++ )
if ( ftc_primes[i] > num )
return ftc_primes[i];
return FTC_PRIMES_MAX;
}
#define FTC_CACHE_RESIZE_TEST( c ) \
( (c)->nodes*3 < (c)->size || \
(c)->size*3 < (c)->nodes )
static void
ftc_cache_resize( FTC_Cache cache )
{
FT_UFast new_size;
new_size = ftc_prime_closest( cache->nodes );
if ( new_size != cache->size )
{
FT_Memory memory = cache->memory;
FT_Error error;
FTC_Node* new_buckets ;
FT_ULong i;
/* no need to report an error; we'll simply keep using the same */
/* buckets number / size */
if ( ALLOC_ARRAY( new_buckets, new_size, FTC_Node ) )
return;
for ( i = 0; i < cache->size; i++ )
{
FTC_Node node, next, *pnode;
FT_UFast hash;
node = cache->buckets[i];
while ( node )
{
next = node->link;
hash = node->hash % new_size;
pnode = new_buckets + hash;
node->link = pnode[0];
pnode[0] = node;
node = next;
}
}
if ( cache->buckets )
FREE( cache->buckets );
cache->buckets = new_buckets;
cache->size = new_size;
FT_UNUSED( error );
}
}
FT_EXPORT_DEF( FT_Error )
ftc_cache_init( FTC_Cache cache )
{
FT_Memory memory = cache->memory;
FTC_Cache_Class clazz = cache->clazz;
FT_Error error;
cache->nodes = 0;
cache->size = FTC_PRIMES_MIN;
if ( ALLOC_ARRAY( cache->buckets, cache->size, FTC_Node ) )
goto Exit;
/* now, initialize the lru list of families for this cache */
if ( clazz->family_size > 0 )
{
FT_LruList_ClassRec* lru_class = &cache->family_class;
lru_class->list_size = sizeof( FT_LruListRec );
lru_class->list_init = NULL;
lru_class->list_done = NULL;
lru_class->node_size = clazz->family_size;
lru_class->node_init = (FT_LruNode_InitFunc) clazz->family_init;
lru_class->node_done = (FT_LruNode_DoneFunc) clazz->family_done;
lru_class->node_flush = (FT_LruNode_FlushFunc) NULL;
lru_class->node_compare = (FT_LruNode_CompareFunc)clazz->family_compare;
error = FT_LruList_New( (FT_LruList_Class) lru_class,
0, /* max items == 0 => unbounded list */
cache,
memory,
&cache->families );
if ( error )
FREE( cache->buckets );
}
Exit:
return error;
}
FT_EXPORT_DEF( void )
ftc_cache_clear( FTC_Cache cache )
{
if ( cache )
{
FT_Memory memory = cache->memory;
FTC_Cache_Class clazz = cache->clazz;
FTC_Manager manager = cache->manager;
FT_UFast i;
for ( i = 0; i < cache->size; i++ )
{
FTC_Node *pnode = cache->buckets + i, next, node = *pnode;
while ( node )
{
next = node->link;
node->link = NULL;
/* remove node from mru list */
ftc_node_mru_unlink( node, manager );
/* now finalize it */
manager->cur_weight -= clazz->node_weight( node, cache );
if ( clazz->node_done )
clazz->node_done( node, cache );
FREE( node );
node = next;
}
cache->buckets[i] = NULL;
}
cache->nodes = 0;
/* destroy the families */
if ( cache->families )
FT_LruList_Reset( cache->families );
}
}
FT_EXPORT_DEF( void )
ftc_cache_done( FTC_Cache cache )
{
if ( cache )
{
FT_Memory memory = cache->memory;
ftc_cache_clear( cache );
FREE( cache->buckets );
cache->size = 0;
if ( cache->families )
{
FT_LruList_Destroy( cache->families );
cache->families = NULL;
}
}
}
/* Look up a node in "top" of its cache's hash table. */
/* If not found, create a new node. */
/* */
FT_EXPORT_DEF( FT_Error )
ftc_cache_lookup( FTC_Cache cache,
FTC_Query query,
FTC_Node *anode )
{
FT_Error error;
FT_LruNode lru;
/* some argument checks are delayed to ftc_glyph_cache_lookup */
if ( !cache || !query || !anode )
return FTC_Err_Invalid_Argument;
*anode = NULL;
query->hash = 0;
query->family = NULL;
error = FT_LruList_Lookup( cache->families, query, &lru );
if ( !error )
{
FTC_Family family = (FTC_Family) lru;
FT_UFast hash = query->hash;
FTC_Node* bucket = cache->buckets + (hash % cache->size);
if ( query->family != family ||
family->fam_index >= cache->manager->families.size )
{
FT_ERROR((
"ftc_cache_lookup: invalid query (bad 'family' field)\n" ));
return FT_Err_Invalid_Argument;
}
if ( *bucket )
{
FTC_Node* pnode = bucket;
FTC_Node_CompareFunc compare = cache->clazz->node_compare;
for ( ;; )
{
FTC_Node node;
node = *pnode;
if ( node == NULL )
break;
if ( (FT_UInt)node->fam_index == family->fam_index &&
compare( node, query, cache ) )
{
/* move to head of bucket list */
if ( pnode != bucket )
{
*pnode = node->link;
node->link = *bucket;
*bucket = node;
}
/* move to head of MRU list */
if ( node != cache->manager->nodes_list )
ftc_node_mru_up( node, cache->manager );
*anode = node;
goto Exit;
}
pnode = &(*pnode)->link;
}
}
/* didn't find a node, create a new one */
{
FTC_Cache_Class clazz = cache->clazz;
FTC_Manager manager = cache->manager;
FT_Memory memory = cache->memory;
FTC_Node node;
if ( ALLOC( node, clazz->node_size ) )
goto Exit;
node->fam_index = (FT_UShort) family->fam_index;
node->hash = query->hash;
node->ref_count = 0;
error = clazz->node_init( node, query, cache );
if ( error )
{
FREE( node );
goto Exit;
}
ftc_node_hash_link( node, cache );
ftc_node_mru_link( node, cache->manager );
cache->manager->cur_weight += clazz->node_weight( node, cache );
/* now try to compress the node pool when necessary */
if ( manager->cur_weight >= manager->max_weight )
{
node->ref_count++;
FTC_Manager_Compress( manager );
node->ref_count--;
}
/* try to resize the hash table if appropriate */
if ( FTC_CACHE_RESIZE_TEST( cache ) )
ftc_cache_resize( cache );
*anode = node;
}
}
Exit:
return error;
}
/* END */