freetype/src/cff/t2objs.c

/***************************************************************************/
/*                                                                         */
/*  t2objs.c                                                               */
/*                                                                         */
/*    OpenType objects manager (body).                                     */
/*                                                                         */
/*  Copyright 1996-2000 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 <freetype/internal/ftdebug.h>
#include <freetype/internal/ftcalc.h>
#include <freetype/internal/ftstream.h>
#include <freetype/fterrors.h>
#include <freetype/ttnameid.h>
#include <freetype/tttags.h>

#include <freetype/internal/sfnt.h>
#include <freetype/internal/psnames.h>

#ifdef FT_FLAT_COMPILE
#include "t2objs.h"
#include "t2load.h"
#else
#include <cff/t2objs.h>
#include <cff/t2load.h>
#endif

#include <freetype/internal/t2errors.h>


  /*************************************************************************/
  /*                                                                       */
  /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
  /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
  /* messages during execution.                                            */
  /*                                                                       */
#undef  FT_COMPONENT
#define FT_COMPONENT  trace_t2objs


  /*************************************************************************/
  /*                                                                       */
  /*                           FACE  FUNCTIONS                             */
  /*                                                                       */
  /*************************************************************************/

  static
  FT_String*   T2_StrCopy( FT_Memory  memory, const FT_String*  source )
  {
    FT_Error   error;
    FT_String* result = 0;
    FT_Int     len = (FT_Int)strlen(source);
    
    if ( !ALLOC( result, len+1 ) )
    {
      MEM_Copy( result, source, len );
      result[len] = 0;
    }
    return result;
  }


  /* this function is used to build a Unicode charmap from the glyph names */
  /* in a file..                                                           */
  static
  FT_Error   CFF_Build_Unicode_Charmap( T2_Face             face,
                                        FT_ULong            base_offset,
                                        PSNames_Interface*  psnames )
  {
    CFF_Font*       font = (CFF_Font*)face->extra.data;
    FT_Memory       memory = FT_FACE_MEMORY(face);
    FT_UInt         n, num_glyphs = face->root.num_glyphs;
    const char**    glyph_names;
    FT_Error        error;
    CFF_Font_Dict*  dict = &font->top_font.font_dict;
    FT_ULong        charset_offset;
    FT_Byte         format;
    FT_Stream       stream = face->root.stream;

    charset_offset = dict->charset_offset;
    if (!charset_offset)
    {
      FT_ERROR(( "CFF.Build_Unicode_Charmap: charset table is missing\n" ));
      error = FT_Err_Invalid_File_Format;
      goto Exit;
    }

    /* seek to charset table and allocate glyph names table */
    if ( FILE_Seek( base_offset + charset_offset )           ||
         ALLOC_ARRAY( glyph_names, num_glyphs, const char* ) )
      goto Exit;

    /* now, read each glyph name and store it in the glyph name table */
    if ( READ_Byte(format) )
      goto Fail;
      
    switch (format)
    {
      case 0:  /* format 0 - one SID per glyph */
        {
          const char**  gname = glyph_names;
          const char**  limit = gname + num_glyphs;
          
          if ( ACCESS_Frame( num_glyphs*2 ) )
            goto Fail;
          
          for ( ; gname < limit; gname++ )
            gname[0] = T2_Get_String( &font->string_index,
                                      GET_UShort(),
                                      psnames );
          FORGET_Frame();
          break;
        }
        
      case 1:  /* format 1 - sequential ranges                    */
      case 2:  /* format 2 - sequential ranges with 16-bit counts */
        {
          const char**  gname = glyph_names;
          const char**  limit = gname + num_glyphs;
          FT_UInt       len = 3;
          
          if (format == 2)
            len++;
          
          while (gname < limit)
          {
            FT_UInt   first;
            FT_UInt   count;
              
            if ( ACCESS_Frame( len ) )
              goto Fail;

            first = GET_UShort();
            if (format == 3)
              count = GET_UShort();
            else
              count = GET_Byte();

            FORGET_Frame();
            
            for ( ; count > 0; count-- )
            {
              gname[0] = T2_Get_String( &font->string_index,
                                        first,
                                        psnames );
              gname++;
              first++;
            }
          }
          break;
        }
        
      default:   /* unknown charset format  !! */
        FT_ERROR(( "CFF: unknown charset format !!\n" ));
        error = FT_Err_Invalid_File_Format;
        goto Fail;
    }

    /* all right, the glyph names were loaded, we now need to create */
    /* the corresponding unicode charmap..                           */

  Fail:
    for ( n = 0; n < num_glyphs; n++ )
      FREE( glyph_names[n] );
      
    FREE( glyph_names );
        
  Exit:
    return error;
  }
  
  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    T2_Init_Face                                                       */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Initializes a given OpenType face object.                          */
  /*                                                                       */
  /* <Input>                                                               */
  /*    stream     :: The source font stream.                              */
  /*                                                                       */
  /*    face_index :: The index of the font face in the resource.          */
  /*                                                                       */
  /*    num_params :: Number of additional generic parameters.  Ignored.   */
  /*                                                                       */
  /*    params     :: Additional generic parameters.  Ignored.             */
  /*                                                                       */
  /* <InOut>                                                               */
  /*    face       :: The newly built face object.                         */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  LOCAL_DEF
  FT_Error  T2_Init_Face( FT_Stream      stream,
                          T2_Face        face,
                          FT_Int         face_index,
                          FT_Int         num_params,
                          FT_Parameter*  params )
  {
    FT_Error            error;
    SFNT_Interface*     sfnt;
    PSNames_Interface*  psnames;
    FT_Bool             pure_cff    = 1;
    FT_Bool             sfnt_format = 0;

    sfnt = (SFNT_Interface*)FT_Get_Module_Interface(
             face->root.driver->root.library, "sfnt" );
    if ( !sfnt )
      goto Bad_Format;

    psnames = (PSNames_Interface*)FT_Get_Module_Interface(
             face->root.driver->root.library, "psnames" );

    /* create input stream from resource */
    if ( FILE_Seek( 0 ) )
      goto Exit;

    /* check that we have a valid OpenType file */
    error = sfnt->init_face( stream, face, face_index, num_params, params );
    if ( !error )
    {
      if ( face->format_tag != 0x4F54544FL )  /* `OTTO'; OpenType/CFF font */
      {
        FT_TRACE2(( "[not a valid OpenType/CFF font]\n" ));
        goto Bad_Format;
      }

      /* If we are performing a simple font format check, exit immediately */
      if ( face_index < 0 )
        return T2_Err_Ok;

      sfnt_format = 1;  

      /* now, the font can be either an OpenType/CFF font, or a SVG CEF font */
      /* in the later case, it doesn't have a "head" table..                 */
      error = face->goto_table( face, TTAG_head, stream, 0 );
      if (!error)
      {
        pure_cff = 0;

        /* Load font directory */
        error = sfnt->load_face( stream, face, face_index, num_params, params );
        if ( error )
          goto Exit;
      }
      else
      {
        /* load the "cmap" table by hand */
        error = sfnt->load_charmaps( face, stream );
        if (error)
          goto Exit;
          
        /* XXX: for now, we don't load the GPOS table, as OpenType Layout */
        /* support will be added later to FreeType 2 as a separate module */
      }

      /* now, load the CFF part of the file */
      error = face->goto_table( face, TTAG_CFF, stream, 0 );
      if ( error )
        goto Exit;
    }
    else
    {
      /* rewind to start of file, we're going to load a pure-CFF font */
      (void)FILE_Seek(0);
      error = FT_Err_Ok;
    }


    /* now load and parse the CFF table in the file */
    {
      CFF_Font*  cff;
      FT_Memory  memory = face->root.memory;
      FT_Face    root;
      FT_UInt    flags;


      if ( ALLOC( cff, sizeof ( *cff ) ) )
        goto Exit;

      face->extra.data = cff;
      error = T2_Load_CFF_Font( stream, face_index, cff );
      if ( error )
        goto Exit;

      /* Complement the root flags with some interesting information. */
      /* Note that this is only necessary for pure CFF and CEF fonts  */
      
      root = &face->root;
      if (pure_cff)
      {
        CFF_Font_Dict*  dict = &cff->top_font.font_dict;
      
        /* we need the psnames module for pure-CFF and CEF formats */
        if (!psnames)
        {
          FT_ERROR(( "cannot open CFF & CEF fonts without the 'psnames' module\n" ));
          goto Bad_Format;
        }
        
        /* compute number of glyphs */
        if (dict->cid_registry)
          root->num_glyphs = dict->cid_count;
        else
          root->num_glyphs = cff->charstrings_index.count;
        
        /* set global bbox, as well as EM size */
        root->units_per_EM = FT_DivFix( 1000L << 16, dict->font_matrix.yy ) >> 16;
        root->bbox         = dict->font_bbox;
        root->ascender     = root->bbox.yMax;
        root->descender    = root->bbox.yMin;
        
        /* retrieve font family & style name */
        root->family_name = T2_Get_Name( &cff->name_index, face_index );
        if (dict->cid_registry)
        {
          root->style_name  = T2_StrCopy( memory, "Regular" );  /* XXXX */
        }
        else
        {
          root->style_name  = T2_Get_String( &cff->string_index,
                                             dict->weight,
                                             psnames );
        }
        
          /*********************************************************************/
          /*                                                                   */
          /* Compute face flags.                                               */
          /*                                                                   */
          flags = FT_FACE_FLAG_SCALABLE  |    /* scalable outlines */
                  FT_FACE_FLAG_HORIZONTAL;    /* horizontal data   */

          if (sfnt_format)
            flags |= FT_FACE_FLAG_SFNT;
    
          /* fixed width font? */
          if ( dict->is_fixed_pitch )
            flags |= FT_FACE_FLAG_FIXED_WIDTH;

/* XXXX: WE DO NOT SUPPORT KERNING METRICS IN THE GPOS TABLE FOR NOW */
#if 0
          /* kerning available ? */
          if ( face->kern_pairs )
            flags |= FT_FACE_FLAG_KERNING;
#endif

          root->face_flags = flags;
    
          /*********************************************************************/
          /*                                                                   */
          /* Compute style flags.                                              */
          /*                                                                   */
          flags = 0;
    
          if ( dict->italic_angle )
            flags |= FT_STYLE_FLAG_ITALIC;
            
          /* XXXX : may not be correct .. */
          if ( cff->top_font.private_dict.force_bold )
            flags |= FT_STYLE_FLAG_BOLD;
            
          root->style_flags = flags;
      }
    }
    
  Exit:
    return error;

  Bad_Format:
    error = FT_Err_Unknown_File_Format;
    goto Exit;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    T2_Done_Face                                                       */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Finalizes a given face object.                                     */
  /*                                                                       */
  /* <Input>                                                               */
  /*    face :: A pointer to the face object to destroy.                   */
  /*                                                                       */
  LOCAL_DEF
  void  T2_Done_Face( T2_Face  face )
  {
    FT_Memory        memory = face->root.memory;
    SFNT_Interface*  sfnt   = (SFNT_Interface*)face->sfnt;


    if ( sfnt )
      sfnt->done_face( face );

    {
      CFF_Font*  cff = (CFF_Font*)face->extra.data;


      if ( cff )
      {
        T2_Done_CFF_Font( cff );
        FREE( face->extra.data );
      }
    }
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    T2_Init_Driver                                                     */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Initializes a given OpenType driver object.                        */
  /*                                                                       */
  /* <Input>                                                               */
  /*    driver :: A handle to the target driver object.                    */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  LOCAL_FUNC
  FT_Error  T2_Init_Driver( T2_Driver  driver )
  {
    /* init extension registry if needed */

#ifdef TT_CONFIG_OPTION_EXTEND_ENGINE

    return TT_Init_Extensions( driver );

#else

    FT_UNUSED( driver );

    return T2_Err_Ok;

#endif
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    T2_Done_Driver                                                     */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Finalizes a given OpenType driver.                                 */
  /*                                                                       */
  /* <Input>                                                               */
  /*    driver :: A handle to the target OpenType driver.                  */
  /*                                                                       */
  LOCAL_FUNC
  void  T2_Done_Driver( T2_Driver  driver )
  {
    /* destroy extensions registry if needed */

#ifdef TT_CONFIG_OPTION_EXTEND_ENGINE

    TT_Done_Extensions( driver );

#else

    FT_UNUSED( driver );

#endif
  }


/* END */