ftcmanag.c

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    if ( max_sizes == 0 )
      max_sizes = FTC_MAX_SIZES_DEFAULT;

    if ( max_bytes == 0 )
      max_bytes = FTC_MAX_BYTES_DEFAULT;

    manager->library      = library;
    manager->memory       = memory;
    manager->max_weight   = max_bytes;

    manager->request_face = requester;
    manager->request_data = req_data;

    FTC_MruList_Init( &manager->faces,
                      &ftc_face_list_class,
                      max_faces,
                      manager,
                      memory );

    FTC_MruList_Init( &manager->sizes,
                      &ftc_size_list_class,
                      max_sizes,
                      manager,
                      memory );

    *amanager = manager;

  Exit:
    return error;
  }


  /* documentation is in ftcache.h */

  FT_EXPORT_DEF( void )
  FTC_Manager_Done( FTC_Manager  manager )
  {
    FT_Memory  memory;
    FT_UInt    idx;


    if ( !manager || !manager->library )
      return;

    memory = manager->memory;

    /* now discard all caches */
    for (idx = manager->num_caches; idx-- > 0; )
    {
      FTC_Cache  cache = manager->caches[idx];


      if ( cache )
      {
        cache->clazz.cache_done( cache );
        FT_FREE( cache );
        manager->caches[idx] = NULL;
      }
    }
    manager->num_caches = 0;

    /* discard faces and sizes */
    FTC_MruList_Done( &manager->sizes );
    FTC_MruList_Done( &manager->faces );

    manager->library = NULL;
    manager->memory  = NULL;

    FT_FREE( manager );
  }


  /* documentation is in ftcache.h */

  FT_EXPORT_DEF( void )
  FTC_Manager_Reset( FTC_Manager  manager )
  {
    if ( manager )
    {
      FTC_MruList_Reset( &manager->sizes );
      FTC_MruList_Reset( &manager->faces );
    }
    /* XXX: FIXME: flush the caches? */
  }


#ifdef FT_DEBUG_ERROR

  static void
  FTC_Manager_Check( FTC_Manager  manager )
  {
    FTC_Node  node, first;


    first = manager->nodes_list;

    /* check node weights */
    if ( first )
    {
      FT_ULong  weight = 0;


      node = first;

      do
      {
        FTC_Cache  cache = manager->caches[node->cache_index];


        if ( (FT_UInt)node->cache_index >= manager->num_caches )
          FT_ERROR(( "FTC_Manager_Check: invalid node (cache index = %ld\n",
                     node->cache_index ));
        else
          weight += cache->clazz.node_weight( node, cache );

        node = FTC_NODE__NEXT( node );

      } while ( node != first );

      if ( weight != manager->cur_weight )
        FT_ERROR(( "FTC_Manager_Check: invalid weight %ld instead of %ld\n",
                   manager->cur_weight, weight ));
    }

    /* check circular list */
    if ( first )
    {
      FT_UFast  count = 0;


      node = first;
      do
      {
        count++;
        node = FTC_NODE__NEXT( node );

      } while ( node != first );

      if ( count != manager->num_nodes )
        FT_ERROR((
          "FTC_Manager_Check: invalid cache node count %d instead of %d\n",
          manager->num_nodes, count ));
    }
  }

#endif /* FT_DEBUG_ERROR */


  /* `Compress' the manager's data, i.e., get rid of old cache nodes */
  /* that are not referenced anymore in order to limit the total     */
  /* memory used by the cache.                                       */

  /* documentation is in ftcmanag.h */

  FT_LOCAL_DEF( void )
  FTC_Manager_Compress( FTC_Manager  manager )
  {
    FTC_Node   node, first;


    if ( !manager )
      return;

    first = manager->nodes_list;

#ifdef FT_DEBUG_ERROR
    FTC_Manager_Check( manager );

    FT_ERROR(( "compressing, weight = %ld, max = %ld, nodes = %d\n",
               manager->cur_weight, manager->max_weight,
               manager->num_nodes ));
#endif

    if ( manager->cur_weight < manager->max_weight || first == NULL )
      return;

    /* go to last node -- it's a circular list */
    node = FTC_NODE__PREV( first );
    do
    {
      FTC_Node  prev;


      prev = ( node == first ) ? NULL : FTC_NODE__PREV( node );

      if ( node->ref_count <= 0 )
        ftc_node_destroy( node, manager );

      node = prev;

    } while ( node && manager->cur_weight > manager->max_weight );
  }


  /* documentation is in ftcmanag.h */

  FT_LOCAL_DEF( FT_Error )
  FTC_Manager_RegisterCache( FTC_Manager      manager,
                             FTC_CacheClass   clazz,
                             FTC_Cache       *acache )
  {
    FT_Error   error = FTC_Err_Invalid_Argument;
    FTC_Cache  cache = NULL;


    if ( manager && clazz && acache )
    {
      FT_Memory  memory = manager->memory;


      if ( manager->num_caches >= FTC_MAX_CACHES )
      {
        error = FTC_Err_Too_Many_Caches;
        FT_ERROR(( "%s: too many registered caches\n",
                   "FTC_Manager_Register_Cache" ));
        goto Exit;
      }

      if ( !FT_ALLOC( cache, clazz->cache_size ) )
      {
        cache->manager   = manager;
        cache->memory    = memory;
        cache->clazz     = clazz[0];
        cache->org_class = clazz;

        /* THIS IS VERY IMPORTANT!  IT WILL WRETCH THE MANAGER */
        /* IF IT IS NOT SET CORRECTLY                          */
        cache->index = manager->num_caches;

        error = clazz->cache_init( cache );
        if ( error )
        {
          clazz->cache_done( cache );
          FT_FREE( cache );
          goto Exit;
        }

        manager->caches[manager->num_caches++] = cache;
      }
    }

  Exit:
    *acache = cache;
    return error;
  }


  FT_LOCAL_DEF( FT_UInt )
  FTC_Manager_FlushN( FTC_Manager  manager,
                      FT_UInt      count )
  {
    FTC_Node  first = manager->nodes_list;
    FTC_Node  node;
    FT_UInt   result;


    /* try to remove `count' nodes from the list */
    if ( first == NULL )  /* empty list! */
      return 0;

    /* go to last node - it's a circular list */
    node = FTC_NODE__PREV(first);
    for ( result = 0; result < count; )
    {
      FTC_Node  prev = FTC_NODE__PREV( node );


      /* don't touch locked nodes */
      if ( node->ref_count <= 0 )
      {
        ftc_node_destroy( node, manager );
        result++;
      }

      if ( node == first )
        break;

      node = prev;
    }
    return  result;
  }


  /* documentation is in ftcache.h */

  FT_EXPORT_DEF( void )
  FTC_Manager_RemoveFaceID( FTC_Manager  manager,
                            FTC_FaceID   face_id )
  {
    FT_UInt  nn;

    /* this will remove all FTC_SizeNode that correspond to
     * the face_id as well
     */
    FTC_MruList_RemoveSelection( &manager->faces, NULL, face_id );

    for ( nn = 0; nn < manager->num_caches; nn++ )
      FTC_Cache_RemoveFaceID( manager->caches[nn], face_id );
  }


  /* documentation is in ftcache.h */

  FT_EXPORT_DEF( void )
  FTC_Node_Unref( FTC_Node     node,
                  FTC_Manager  manager )
  {
    if ( node && (FT_UInt)node->cache_index < manager->num_caches )
      node->ref_count--;
  }


#ifdef FT_CONFIG_OPTION_OLD_INTERNALS

  FT_EXPORT_DEF( FT_Error )
  FTC_Manager_Lookup_Face( FTC_Manager  manager,
                           FTC_FaceID   face_id,
                           FT_Face     *aface )
  {
    return FTC_Manager_LookupFace( manager, face_id, aface );
  }


  FT_EXPORT( FT_Error )
  FTC_Manager_Lookup_Size( FTC_Manager  manager,
                           FTC_Font     font,
                           FT_Face     *aface,
                           FT_Size     *asize )
  {
    FTC_ScalerRec  scaler;
    FT_Error       error;
    FT_Size        size;
    FT_Face        face;


    scaler.face_id = font->face_id;
    scaler.width   = font->pix_width;
    scaler.height  = font->pix_height;
    scaler.pixel   = TRUE;
    scaler.x_res   = 0;
    scaler.y_res   = 0;

    error = FTC_Manager_LookupSize( manager, &scaler, &size );
    if ( error )
    {
      face = NULL;
      size = NULL;
    }
    else
      face = size->face;

    if ( aface )
      *aface = face;

    if ( asize )
      *asize = size;

    return error;
  }

#endif /* FT_CONFIG_OPTION_OLD_INTERNALS */


/* END */