ftobjs.c

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/***************************************************************************/
/*                                                                         */
/*  ftobjs.c                                                               */
/*                                                                         */
/*    The FreeType private base classes (body).                            */
/*                                                                         */
/*  Copyright 1996-2001, 2002, 2003, 2004, 2005, 2006, 2007 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_LIST_H
#include FT_OUTLINE_H
#include FT_INTERNAL_VALIDATE_H
#include FT_INTERNAL_OBJECTS_H
#include FT_INTERNAL_DEBUG_H
#include FT_INTERNAL_RFORK_H
#include FT_INTERNAL_STREAM_H
#include FT_INTERNAL_SFNT_H    /* for SFNT_Load_Table_Func */
#include FT_TRUETYPE_TABLES_H
#include FT_TRUETYPE_IDS_H
#include FT_OUTLINE_H

#include FT_SERVICE_SFNT_H
#include FT_SERVICE_POSTSCRIPT_NAME_H
#include FT_SERVICE_GLYPH_DICT_H
#include FT_SERVICE_TT_CMAP_H
#include FT_SERVICE_KERNING_H
#include FT_SERVICE_TRUETYPE_ENGINE_H

#define GRID_FIT_METRICS

  FT_BASE_DEF( FT_Pointer )
  ft_service_list_lookup( FT_ServiceDesc  service_descriptors,
                          const char*     service_id )
  {
    FT_Pointer      result = NULL;
    FT_ServiceDesc  desc   = service_descriptors;


    if ( desc && service_id )
    {
      for ( ; desc->serv_id != NULL; desc++ )
      {
        if ( ft_strcmp( desc->serv_id, service_id ) == 0 )
        {
          result = (FT_Pointer)desc->serv_data;
          break;
        }
      }
    }

    return result;
  }


  FT_BASE_DEF( void )
  ft_validator_init( FT_Validator        valid,
                     const FT_Byte*      base,
                     const FT_Byte*      limit,
                     FT_ValidationLevel  level )
  {
    valid->base  = base;
    valid->limit = limit;
    valid->level = level;
    valid->error = FT_Err_Ok;
  }


  FT_BASE_DEF( FT_Int )
  ft_validator_run( FT_Validator  valid )
  {
    /* This function doesn't work!  None should call it. */
    FT_UNUSED( valid );

    return -1;
  }


  FT_BASE_DEF( void )
  ft_validator_error( FT_Validator  valid,
                      FT_Error      error )
  {
    /* since the cast below also disables the compiler's */
    /* type check, we introduce a dummy variable, which  */
    /* will be optimized away                            */
    volatile jmp_buf* jump_buffer = &valid->jump_buffer;


    valid->error = error;

    /* throw away volatileness; use `jump_buffer' or the  */
    /* compiler may warn about an unused local variable   */
    ft_longjmp( *(jmp_buf*) jump_buffer, 1 );
  }


  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/
  /****                                                                 ****/
  /****                                                                 ****/
  /****                           S T R E A M                           ****/
  /****                                                                 ****/
  /****                                                                 ****/
  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/


  /* create a new input stream from an FT_Open_Args structure */
  /*                                                          */
  FT_BASE_DEF( FT_Error )
  FT_Stream_New( FT_Library           library,
                 const FT_Open_Args*  args,
                 FT_Stream           *astream )
  {
    FT_Error   error;
    FT_Memory  memory;
    FT_Stream  stream;


    if ( !library )
      return FT_Err_Invalid_Library_Handle;

    if ( !args )
      return FT_Err_Invalid_Argument;

    *astream = 0;
    memory   = library->memory;

    if ( FT_NEW( stream ) )
      goto Exit;

    stream->memory = memory;

    if ( args->flags & FT_OPEN_MEMORY )
    {
      /* create a memory-based stream */
      FT_Stream_OpenMemory( stream,
                            (const FT_Byte*)args->memory_base,
                            args->memory_size );
    }
    else if ( args->flags & FT_OPEN_PATHNAME )
    {
      /* create a normal system stream */
      error = FT_Stream_Open( stream, args->pathname );
      stream->pathname.pointer = args->pathname;
    }
    else if ( ( args->flags & FT_OPEN_STREAM ) && args->stream )
    {
      /* use an existing, user-provided stream */

      /* in this case, we do not need to allocate a new stream object */
      /* since the caller is responsible for closing it himself       */
      FT_FREE( stream );
      stream = args->stream;
    }
    else
      error = FT_Err_Invalid_Argument;

    if ( error )
      FT_FREE( stream );
    else
      stream->memory = memory;  /* just to be certain */

    *astream = stream;

  Exit:
    return error;
  }


  FT_BASE_DEF( void )
  FT_Stream_Free( FT_Stream  stream,
                  FT_Int     external )
  {
    if ( stream )
    {
      FT_Memory  memory = stream->memory;


      FT_Stream_Close( stream );

      if ( !external )
        FT_FREE( stream );
    }
  }


#undef  FT_COMPONENT
#define FT_COMPONENT  trace_objs


  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/
  /****                                                                 ****/
  /****                                                                 ****/
  /****               FACE, SIZE & GLYPH SLOT OBJECTS                   ****/
  /****                                                                 ****/
  /****                                                                 ****/
  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/


  static FT_Error
  ft_glyphslot_init( FT_GlyphSlot  slot )
  {
    FT_Driver         driver = slot->face->driver;
    FT_Driver_Class   clazz  = driver->clazz;
    FT_Memory         memory = driver->root.memory;
    FT_Error          error  = FT_Err_Ok;
    FT_Slot_Internal  internal;


    slot->library = driver->root.library;

    if ( FT_NEW( internal ) )
      goto Exit;

    slot->internal = internal;

    if ( FT_DRIVER_USES_OUTLINES( driver ) )
      error = FT_GlyphLoader_New( memory, &internal->loader );

    if ( !error && clazz->init_slot )
      error = clazz->init_slot( slot );

  Exit:
    return error;
  }


  FT_BASE_DEF( void )
  ft_glyphslot_free_bitmap( FT_GlyphSlot  slot )
  {
    if ( slot->internal->flags & FT_GLYPH_OWN_BITMAP )
    {
      FT_Memory  memory = FT_FACE_MEMORY( slot->face );


      FT_FREE( slot->bitmap.buffer );
      slot->internal->flags &= ~FT_GLYPH_OWN_BITMAP;
    }
    else
    {
      /* assume that the bitmap buffer was stolen or not */
      /* allocated from the heap                         */
      slot->bitmap.buffer = NULL;
    }
  }


  FT_BASE_DEF( void )
  ft_glyphslot_set_bitmap( FT_GlyphSlot  slot,
                           FT_Byte*      buffer )
  {
    ft_glyphslot_free_bitmap( slot );

    slot->bitmap.buffer = buffer;

    FT_ASSERT( (slot->internal->flags & FT_GLYPH_OWN_BITMAP) == 0 );
  }


  FT_BASE_DEF( FT_Error )
  ft_glyphslot_alloc_bitmap( FT_GlyphSlot  slot,
                             FT_ULong      size )
  {
    FT_Memory  memory = FT_FACE_MEMORY( slot->face );
    FT_Error   error;


    if ( slot->internal->flags & FT_GLYPH_OWN_BITMAP )
      FT_FREE( slot->bitmap.buffer );
    else
      slot->internal->flags |= FT_GLYPH_OWN_BITMAP;

    (void)FT_ALLOC( slot->bitmap.buffer, size );
    return error;
  }


  static void
  ft_glyphslot_clear( FT_GlyphSlot  slot )
  {
    /* free bitmap if needed */
    ft_glyphslot_free_bitmap( slot );

    /* clear all public fields in the glyph slot */
    FT_ZERO( &slot->metrics );
    FT_ZERO( &slot->outline );

    slot->bitmap.width      = 0;
    slot->bitmap.rows       = 0;
    slot->bitmap.pitch      = 0;
    slot->bitmap.pixel_mode = 0;
    /* `slot->bitmap.buffer' has been handled by ft_glyphslot_free_bitmap */

    slot->bitmap_left   = 0;
    slot->bitmap_top    = 0;
    slot->num_subglyphs = 0;
    slot->subglyphs     = 0;
    slot->control_data  = 0;
    slot->control_len   = 0;
    slot->other         = 0;
    slot->format        = FT_GLYPH_FORMAT_NONE;

    slot->linearHoriAdvance = 0;
    slot->linearVertAdvance = 0;
    slot->lsb_delta         = 0;
    slot->rsb_delta         = 0;
  }


  static void
  ft_glyphslot_done( FT_GlyphSlot  slot )
  {
    FT_Driver        driver = slot->face->driver;
    FT_Driver_Class  clazz  = driver->clazz;
    FT_Memory        memory = driver->root.memory;


    if ( clazz->done_slot )
      clazz->done_slot( slot );

    /* free bitmap buffer if needed */
    ft_glyphslot_free_bitmap( slot );

    /* free glyph loader */
    if ( FT_DRIVER_USES_OUTLINES( driver ) )
    {
      FT_GlyphLoader_Done( slot->internal->loader );
      slot->internal->loader = 0;
    }

    FT_FREE( slot->internal );
  }


  /* documentation is in ftobjs.h */

  FT_BASE_DEF( FT_Error )
  FT_New_GlyphSlot( FT_Face        face,
                    FT_GlyphSlot  *aslot )
  {
    FT_Error         error;
    FT_Driver        driver;
    FT_Driver_Class  clazz;
    FT_Memory        memory;
    FT_GlyphSlot     slot;


    if ( !face || !face->driver )
      return FT_Err_Invalid_Argument;

    driver = face->driver;
    clazz  = driver->clazz;
    memory = driver->root.memory;

    FT_TRACE4(( "FT_New_GlyphSlot: Creating new slot object\n" ));
    if ( !FT_ALLOC( slot, clazz->slot_object_size ) )
    {
      slot->face = face;

      error = ft_glyphslot_init( slot );
      if ( error )
      {
        ft_glyphslot_done( slot );
        FT_FREE( slot );
        goto Exit;
      }

      slot->next  = face->glyph;
      face->glyph = slot;

      if ( aslot )
        *aslot = slot;
    }
    else if ( aslot )
      *aslot = 0;


  Exit:
    FT_TRACE4(( "FT_New_GlyphSlot: Return %d\n", error ));
    return error;
  }


  /* documentation is in ftobjs.h */

  FT_BASE_DEF( void )
  FT_Done_GlyphSlot( FT_GlyphSlot  slot )
  {
    if ( slot )
    {
      FT_Driver     driver = slot->face->driver;
      FT_Memory     memory = driver->root.memory;
      FT_GlyphSlot  prev;
      FT_GlyphSlot  cur;


      /* Remove slot from its parent face's list */
      prev = NULL;
      cur  = slot->face->glyph;

      while ( cur )
      {
        if ( cur == slot )
        {
          if ( !prev )
            slot->face->glyph = cur->next;
          else
            prev->next = cur->next;

          ft_glyphslot_done( slot );
          FT_FREE( slot );
          break;
        }
        prev = cur;
        cur  = cur->next;
      }
    }
  }


  /* documentation is in freetype.h */

  FT_EXPORT_DEF( void )
  FT_Set_Transform( FT_Face     face,
                    FT_Matrix*  matrix,
                    FT_Vector*  delta )