ftcmanag.c

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/***************************************************************************/
/*                                                                         */
/*  ftcmanag.c                                                             */
/*                                                                         */
/*    FreeType Cache Manager (body).                                       */
/*                                                                         */
/*  Copyright 2000-2001, 2002, 2003, 2004, 2005, 2006 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_H
#include "ftcmanag.h"
#include FT_INTERNAL_OBJECTS_H
#include FT_INTERNAL_DEBUG_H
#include FT_SIZES_H

#include "ftccback.h"
#include "ftcerror.h"


#undef  FT_COMPONENT
#define FT_COMPONENT  trace_cache

#define FTC_LRU_GET_MANAGER( lru )  ( (FTC_Manager)(lru)->user_data )


  static FT_Error
  ftc_scaler_lookup_size( FTC_Manager  manager,
                          FTC_Scaler   scaler,
                          FT_Size     *asize )
  {
    FT_Face   face;
    FT_Size   size = NULL;
    FT_Error  error;


    error = FTC_Manager_LookupFace( manager, scaler->face_id, &face );
    if ( error )
      goto Exit;

    error = FT_New_Size( face, &size );
    if ( error )
      goto Exit;

    FT_Activate_Size( size );

    if ( scaler->pixel )
      error = FT_Set_Pixel_Sizes( face, scaler->width, scaler->height );
    else
      error = FT_Set_Char_Size( face, scaler->width, scaler->height,
                                scaler->x_res, scaler->y_res );
    if ( error )
    {
      FT_Done_Size( size );
      size = NULL;
    }

  Exit:
    *asize = size;
    return error;
  }


  typedef struct  FTC_SizeNodeRec_
  {
    FTC_MruNodeRec  node;
    FT_Size         size;
    FTC_ScalerRec   scaler;

  } FTC_SizeNodeRec, *FTC_SizeNode;


  FT_CALLBACK_DEF( void )
  ftc_size_node_done( FTC_MruNode  ftcnode,
                      FT_Pointer   data )
  {
    FTC_SizeNode  node = (FTC_SizeNode)ftcnode;
    FT_Size       size = node->size;
    FT_UNUSED( data );


    if ( size )
      FT_Done_Size( size );
  }


  FT_CALLBACK_DEF( FT_Bool )
  ftc_size_node_compare( FTC_MruNode  ftcnode,
                         FT_Pointer   ftcscaler )
  {
    FTC_SizeNode  node    = (FTC_SizeNode)ftcnode;
    FTC_Scaler    scaler  = (FTC_Scaler)ftcscaler;
    FTC_Scaler    scaler0 = &node->scaler;


    if ( FTC_SCALER_COMPARE( scaler0, scaler ) )
    {
      FT_Activate_Size( node->size );
      return 1;
    }
    return 0;
  }


  FT_CALLBACK_DEF( FT_Error )
  ftc_size_node_init( FTC_MruNode  ftcnode,
                      FT_Pointer   ftcscaler,
                      FT_Pointer   ftcmanager )
  {
    FTC_SizeNode  node    = (FTC_SizeNode)ftcnode;
    FTC_Scaler    scaler  = (FTC_Scaler)ftcscaler;
    FTC_Manager   manager = (FTC_Manager)ftcmanager;


    node->scaler = scaler[0];

    return ftc_scaler_lookup_size( manager, scaler, &node->size );
  }


  FT_CALLBACK_DEF( FT_Error )
  ftc_size_node_reset( FTC_MruNode  ftcnode,
                       FT_Pointer   ftcscaler,
                       FT_Pointer   ftcmanager )
  {
    FTC_SizeNode  node    = (FTC_SizeNode)ftcnode;
    FTC_Scaler    scaler  = (FTC_Scaler)ftcscaler;
    FTC_Manager   manager = (FTC_Manager)ftcmanager;


    FT_Done_Size( node->size );

    node->scaler = scaler[0];

    return ftc_scaler_lookup_size( manager, scaler, &node->size );
  }


  FT_CALLBACK_TABLE_DEF
  const FTC_MruListClassRec  ftc_size_list_class =
  {
    sizeof ( FTC_SizeNodeRec ),
    ftc_size_node_compare,
    ftc_size_node_init,
    ftc_size_node_reset,
    ftc_size_node_done
  };


  /* helper function used by ftc_face_node_done */
  static FT_Bool
  ftc_size_node_compare_faceid( FTC_MruNode  ftcnode,
                                FT_Pointer   ftcface_id )
  {
    FTC_SizeNode  node    = (FTC_SizeNode)ftcnode;
    FTC_FaceID    face_id = (FTC_FaceID)ftcface_id;


    return FT_BOOL( node->scaler.face_id == face_id );
  }


  /* documentation is in ftcache.h */

  FT_EXPORT_DEF( FT_Error )
  FTC_Manager_LookupSize( FTC_Manager  manager,
                          FTC_Scaler   scaler,
                          FT_Size     *asize )
  {
    FT_Error      error;
    FTC_SizeNode  node;


    if ( asize == NULL )
      return FTC_Err_Bad_Argument;

    *asize = NULL;

    if ( !manager )
      return FTC_Err_Invalid_Cache_Handle;

#ifdef FTC_INLINE

    FTC_MRULIST_LOOKUP_CMP( &manager->sizes, scaler, ftc_size_node_compare,
                            node, error );

#else
    error = FTC_MruList_Lookup( &manager->sizes, scaler, (FTC_MruNode*)&node );
#endif

    if ( !error )
      *asize = node->size;

    return error;
  }


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****                    FACE MRU IMPLEMENTATION                    *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/

  typedef struct  FTC_FaceNodeRec_
  {
    FTC_MruNodeRec  node;
    FTC_FaceID      face_id;
    FT_Face         face;

  } FTC_FaceNodeRec, *FTC_FaceNode;


  FT_CALLBACK_DEF( FT_Error )
  ftc_face_node_init( FTC_MruNode  ftcnode,
                      FT_Pointer   ftcface_id,
                      FT_Pointer   ftcmanager )
  {
    FTC_FaceNode  node    = (FTC_FaceNode)ftcnode;
    FTC_FaceID    face_id = (FTC_FaceID)ftcface_id;
    FTC_Manager   manager = (FTC_Manager)ftcmanager;
    FT_Error      error;


    node->face_id = face_id;

    error = manager->request_face( face_id,
                                   manager->library,
                                   manager->request_data,
                                   &node->face );
    if ( !error )
    {
      /* destroy initial size object; it will be re-created later */
      if ( node->face->size )
        FT_Done_Size( node->face->size );
    }

    return error;
  }


  FT_CALLBACK_DEF( void )
  ftc_face_node_done( FTC_MruNode  ftcnode,
                      FT_Pointer   ftcmanager )
  {
    FTC_FaceNode  node    = (FTC_FaceNode)ftcnode;
    FTC_Manager   manager = (FTC_Manager)ftcmanager;


    /* we must begin by removing all scalers for the target face */
    /* from the manager's list                                   */
    FTC_MruList_RemoveSelection( &manager->sizes,
                                 ftc_size_node_compare_faceid,
                                 node->face_id );

    /* all right, we can discard the face now */
    FT_Done_Face( node->face );
    node->face    = NULL;
    node->face_id = NULL;
  }


  FT_CALLBACK_DEF( FT_Bool )
  ftc_face_node_compare( FTC_MruNode  ftcnode,
                         FT_Pointer   ftcface_id )
  {
    FTC_FaceNode  node    = (FTC_FaceNode)ftcnode;
    FTC_FaceID    face_id = (FTC_FaceID)ftcface_id;


    return FT_BOOL( node->face_id == face_id );
  }


  FT_CALLBACK_TABLE_DEF
  const FTC_MruListClassRec  ftc_face_list_class =
  {
    sizeof ( FTC_FaceNodeRec),

    ftc_face_node_compare,
    ftc_face_node_init,
    0,                          /* FTC_MruNode_ResetFunc */
    ftc_face_node_done
  };


  /* documentation is in ftcache.h */

  FT_EXPORT_DEF( FT_Error )
  FTC_Manager_LookupFace( FTC_Manager  manager,
                          FTC_FaceID   face_id,
                          FT_Face     *aface )
  {
    FT_Error      error;
    FTC_FaceNode  node;


    if ( aface == NULL )
      return FTC_Err_Bad_Argument;

    *aface = NULL;

    if ( !manager )
      return FTC_Err_Invalid_Cache_Handle;

    /* we break encapsulation for the sake of speed */
#ifdef FTC_INLINE

    FTC_MRULIST_LOOKUP_CMP( &manager->faces, face_id, ftc_face_node_compare,
                            node, error );

#else
    error = FTC_MruList_Lookup( &manager->faces, face_id, (FTC_MruNode*)&node );
#endif

    if ( !error )
      *aface = node->face;

    return error;
  }


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****                    CACHE MANAGER ROUTINES                     *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/


  /* documentation is in ftcache.h */

  FT_EXPORT_DEF( FT_Error )
  FTC_Manager_New( FT_Library          library,
                   FT_UInt             max_faces,
                   FT_UInt             max_sizes,
                   FT_ULong            max_bytes,
                   FTC_Face_Requester  requester,
                   FT_Pointer          req_data,
                   FTC_Manager        *amanager )
  {
    FT_Error     error;
    FT_Memory    memory;
    FTC_Manager  manager = 0;


    if ( !library )
      return FTC_Err_Invalid_Library_Handle;

    memory = library->memory;

    if ( FT_NEW( manager ) )
      goto Exit;

    if ( max_faces == 0 )
      max_faces = FTC_MAX_FACES_DEFAULT;