ref: 5ae1bad3f6f1c842a6f87d8c6e1e5c0237eb236b
dir: /src/cff/t2load.c/
/***************************************************************************/
/* */
/* t2load.c */
/* */
/* TrueType glyph data/program tables loader (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/ftobjs.h>
#include <freetype/internal/ftstream.h>
#include <freetype/internal/psnames.h>
#include <freetype/internal/t2errors.h>
#include <freetype/tttags.h>
#include <t2load.h>
#include <t2parse.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_t2load
/* read a CFF offset from memory */
static
FT_ULong t2_get_offset( FT_Byte* p,
FT_Byte off_size )
{
FT_ULong result;
for ( result = 0; off_size > 0; off_size-- )
result = ( result <<= 8 ) | *p++;
return result;
}
static
FT_Error t2_new_cff_index( CFF_Index* index,
FT_Stream stream,
FT_Bool load )
{
FT_Error error;
FT_Memory memory = stream->memory;
FT_UShort count;
MEM_Set( index, 0, sizeof ( *index ) );
index->stream = stream;
if ( !READ_UShort( count ) &&
count > 0 )
{
FT_Byte* p;
FT_Byte offsize;
FT_ULong data_size;
FT_ULong* poff;
/* there is at least one element; read the offset size */
/* then access the offset table to compute the index's total size */
if ( READ_Byte( offsize ) )
goto Exit;
index->stream = stream;
index->count = count;
index->off_size = offsize;
data_size = (FT_ULong)( count + 1 ) * offsize;
if ( ALLOC_ARRAY( index->offsets, count + 1, FT_ULong ) ||
ACCESS_Frame( data_size ) )
goto Exit;
poff = index->offsets;
p = (FT_Byte*)stream->cursor;
for ( ; (FT_Short)count >= 0; count-- )
{
poff[0] = t2_get_offset( p, offsize );
poff++;
p += offsize;
}
FORGET_Frame();
index->data_offset = FILE_Pos();
data_size = poff[-1] - 1;
if ( load )
{
/* load the data */
if ( EXTRACT_Frame( data_size, index->bytes ) )
goto Exit;
}
else
{
/* skip the data */
(void)FILE_Skip( data_size );
}
}
Exit:
if ( error )
FREE( index->offsets );
return error;
}
static
void t2_done_cff_index( CFF_Index* index )
{
if ( index->stream )
{
FT_Stream stream = index->stream;
FT_Memory memory = stream->memory;
if ( index->bytes )
RELEASE_Frame( index->bytes );
FREE( index->offsets );
MEM_Set( index, 0, sizeof ( *index ) );
}
}
static
FT_Error t2_explicit_cff_index( CFF_Index* index,
FT_Byte*** table )
{
FT_Error error = 0;
FT_Memory memory = index->stream->memory;
FT_UInt n, offset, old_offset;
FT_Byte** t;
*table = 0;
if ( index->count > 0 && !ALLOC_ARRAY( t, index->count + 1, FT_Byte* ) )
{
old_offset = 1;
for ( n = 0; n <= index->count; n++ )
{
offset = index->offsets[n];
if ( !offset )
offset = old_offset;
t[n] = index->bytes + offset - 1;
old_offset = offset;
}
*table = t;
}
return error;
}
LOCAL_FUNC
FT_Error T2_Access_Element( CFF_Index* index,
FT_UInt element,
FT_Byte** pbytes,
FT_ULong* pbyte_len )
{
FT_Error error = 0;
if ( index && index->count > element )
{
/* compute start and end offsets */
FT_ULong off1, off2;
off1 = index->offsets[element];
if ( off1 )
{
do
{
element++;
off2 = index->offsets[element];
}
while ( off2 == 0 && element < index->count );
if ( !off2 )
off1 = 0;
}
/* access element */
if ( off1 )
{
*pbyte_len = off2 - off1;
if ( index->bytes )
{
/* this index was completely loaded in memory, that's easy */
*pbytes = index->bytes + off1 - 1;
}
else
{
/* this index is still on disk/file, access it through a frame */
FT_Stream stream = index->stream;
if ( FILE_Seek( index->data_offset + off1 - 1 ) ||
EXTRACT_Frame( off2 - off1, *pbytes ) )
goto Exit;
}
}
else
{
/* empty index element */
*pbytes = 0;
*pbyte_len = 0;
}
}
else
error = T2_Err_Invalid_Argument;
Exit:
return error;
}
LOCAL_FUNC
void T2_Forget_Element( CFF_Index* index,
FT_Byte** pbytes )
{
if ( index->bytes == 0 )
{
FT_Stream stream = index->stream;
RELEASE_Frame( *pbytes );
}
}
LOCAL_FUNC
FT_String* T2_Get_Name( CFF_Index* index,
FT_UInt element )
{
FT_Memory memory = index->stream->memory;
FT_Byte* bytes;
FT_ULong byte_len;
FT_Error error;
FT_String* name = 0;
error = T2_Access_Element( index, element, &bytes, &byte_len );
if ( error )
goto Exit;
if ( !ALLOC( name, byte_len + 1 ) )
{
MEM_Copy( name, bytes, byte_len );
name[byte_len] = 0;
}
T2_Forget_Element( index, &bytes );
Exit:
return name;
}
#if 0 /* unused until we fully support pure-CFF fonts */
LOCAL_FUNC
FT_String* T2_Get_String( CFF_Index* index,
FT_UInt sid,
PSNames_Interface* interface )
{
/* if it is not a standard string, return it */
if ( sid > 390 )
return T2_Get_Name( index, sid - 390 );
/* that's a standard string, fetch a copy from the PSName module */
{
FT_String* name = 0;
const char* adobe_name = interface->adobe_std_strings( sid );
FT_UInt len;
if ( adobe_name )
{
FT_Memory memory = index->stream->memory;
FT_Error error;
len = (FT_UInt)strlen( adobe_name );
if ( !ALLOC( name, len + 1 ) )
{
MEM_Copy( name, adobe_name, len );
name[len] = 0;
}
}
return name;
}
}
#endif /* 0 */
LOCAL_FUNC
FT_Error T2_Load_CFF_Font( FT_Stream stream,
FT_Int face_index,
CFF_Font* font )
{
static const FT_Frame_Field cff_header_fields[] =
{
FT_FRAME_START( 4 ),
FT_FRAME_BYTE( CFF_Font, version_major ),
FT_FRAME_BYTE( CFF_Font, version_minor ),
FT_FRAME_BYTE( CFF_Font, header_size ),
FT_FRAME_BYTE( CFF_Font, absolute_offsize ),
FT_FRAME_END
};
FT_Error error;
FT_Memory memory = stream->memory;
FT_ULong base_offset;
MEM_Set( font, 0, sizeof ( *font ) );
font->stream = stream;
font->memory = memory;
base_offset = FILE_Pos();
/* read CFF font header */
if ( READ_Fields( cff_header_fields, font ) )
goto Exit;
/* check format */
if ( font->version_major != 1 ||
font->header_size < 4 ||
font->absolute_offsize > 4 )
{
FT_ERROR(( "incorrect CFF font header!\n" ));
error = FT_Err_Unknown_File_Format;
goto Exit;
}
/* skip the rest of the header */
(void)FILE_Skip( font->header_size - 4 );
/* read the name, top dict, string and global subrs index */
error = t2_new_cff_index( &font->name_index, stream, 0 ) ||
t2_new_cff_index( &font->top_dict_index, stream, 0 ) ||
t2_new_cff_index( &font->string_index, stream, 0 ) ||
t2_new_cff_index( &font->global_subrs_index, stream, 1 );
if ( error )
goto Exit;
/* well, we don't really forget the `disabled' fonts... */
font->num_faces = font->name_index.count;
if ( face_index >= font->num_faces )
{
FT_ERROR(( "T2_Load_CFF_Font: incorrect face index = %d\n",
face_index ));
error = T2_Err_Invalid_Argument;
}
/* in case of a font format check, simply exit now */
if ( face_index >= 0 )
{
T2_Parser parser;
FT_Byte* dict;
FT_ULong dict_len;
CFF_Index* index = &font->top_dict_index;
CFF_Top_Dict* top = &font->top_dict;
/* parse the top-level font dictionary */
T2_Parser_Init( &parser, T2CODE_TOPDICT, &font->top_dict );
/* set defaults */
memset( top, 0, sizeof ( *top ) );
top->underline_position = -100;
top->underline_thickness = 50;
top->charstring_type = 2;
top->font_matrix.xx = 0x10000L;
top->font_matrix.yy = 0x10000L;
top->cid_count = 8720;
error = T2_Access_Element( index, face_index, &dict, &dict_len ) ||
T2_Parser_Run( &parser, dict, dict + dict_len );
T2_Forget_Element( &font->top_dict_index, &dict );
if ( error )
goto Exit;
/* parse the private dictionary, if any */
if (font->top_dict.private_offset && font->top_dict.private_size)
{
CFF_Private* priv = &font->private_dict;
/* set defaults */
priv->blue_shift = 7;
priv->blue_fuzz = 1;
priv->lenIV = -1;
priv->expansion_factor = (FT_Fixed)0.06 * 0x10000L;
priv->blue_scale = (FT_Fixed)0.039625 * 0x10000L;
T2_Parser_Init( &parser, T2CODE_PRIVATE, priv );
if ( FILE_Seek( base_offset + font->top_dict.private_offset ) ||
ACCESS_Frame( font->top_dict.private_size ) )
goto Exit;
error = T2_Parser_Run( &parser,
(FT_Byte*)stream->cursor,
(FT_Byte*)stream->limit );
FORGET_Frame();
if ( error )
goto Exit;
}
/* read the charstrings index now */
if ( font->top_dict.charstrings_offset == 0 )
{
FT_ERROR(( "T2_Load_CFF_Font: no charstrings offset!\n" ));
error = FT_Err_Unknown_File_Format;
goto Exit;
}
if ( FILE_Seek( base_offset + font->top_dict.charstrings_offset ) )
goto Exit;
error = t2_new_cff_index( &font->charstrings_index, stream, 0 );
if ( error )
goto Exit;
/* read the local subrs, if any */
if ( font->private_dict.local_subrs_offset )
{
if ( FILE_Seek( base_offset + font->top_dict.private_offset +
font->private_dict.local_subrs_offset ) )
goto Exit;
error = t2_new_cff_index( &font->local_subrs_index, stream, 1 );
if ( error )
goto Exit;
}
/* explicit the global and local subrs */
if ( font->private_dict.local_subrs_offset )
font->num_local_subrs = font->local_subrs_index.count;
else
font->num_local_subrs = 0;
font->num_global_subrs = font->global_subrs_index.count;
error = t2_explicit_cff_index( &font->global_subrs_index,
&font->global_subrs ) ;
if ( font->private_dict.local_subrs_offset )
error |= t2_explicit_cff_index( &font->local_subrs_index,
&font->local_subrs ) ;
if ( error )
goto Exit;
}
/* get the font name */
font->font_name = T2_Get_Name( &font->name_index, face_index );
Exit:
return error;
}
LOCAL_FUNC
void T2_Done_CFF_Font( CFF_Font* font )
{
FT_Memory memory = font->memory;
t2_done_cff_index( &font->global_subrs_index );
t2_done_cff_index( &font->string_index );
t2_done_cff_index( &font->top_dict_index );
t2_done_cff_index( &font->name_index );
t2_done_cff_index( &font->charstrings_index );
FREE( font->local_subrs );
FREE( font->global_subrs );
FREE( font->font_name );
}
/* END */