1
/***************************************************************************/
5
/* TrueTypeGX/AAT kern table validation (body). */
7
/* Copyright 2004, 2005, 2006, 2007 */
8
/* by suzuki toshiya, Masatake YAMATO, Red Hat K.K., */
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/* David Turner, Robert Wilhelm, and Werner Lemberg. */
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/* This file is part of the FreeType project, and may only be used, */
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/* modified, and distributed under the terms of the FreeType project */
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/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
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/* this file you indicate that you have read the license and */
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/* understand and accept it fully. */
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/***************************************************************************/
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/***************************************************************************/
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/* gxvalid is derived from both gxlayout module and otvalid module. */
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/* Development of gxlayout is supported by the Information-technology */
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/* Promotion Agency(IPA), Japan. */
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/***************************************************************************/
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#include FT_SFNT_NAMES_H
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#include FT_SERVICE_GX_VALIDATE_H
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/*************************************************************************/
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/* The macro FT_COMPONENT is used in trace mode. It is an implicit */
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/* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */
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/* messages during execution. */
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#define FT_COMPONENT trace_gxvkern
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/*************************************************************************/
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/*************************************************************************/
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/***** Data and Types *****/
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/*************************************************************************/
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/*************************************************************************/
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typedef enum GXV_kern_Version_
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KERN_VERSION_CLASSIC = 0x0000,
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KERN_VERSION_NEW = 0x0001
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typedef enum GXV_kern_Dialect_
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KERN_DIALECT_UNKNOWN = 0,
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KERN_DIALECT_MS = FT_VALIDATE_MS,
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KERN_DIALECT_APPLE = FT_VALIDATE_APPLE,
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KERN_DIALECT_ANY = FT_VALIDATE_CKERN
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typedef struct GXV_kern_DataRec_
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GXV_kern_Version version;
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GXV_kern_Dialect dialect_request;
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} GXV_kern_DataRec, *GXV_kern_Data;
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#define GXV_KERN_DATA( field ) GXV_TABLE_DATA( kern, field )
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#define KERN_IS_CLASSIC( valid ) \
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( KERN_VERSION_CLASSIC == GXV_KERN_DATA( version ) )
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#define KERN_IS_NEW( valid ) \
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( KERN_VERSION_NEW == GXV_KERN_DATA( version ) )
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#define KERN_DIALECT( valid ) \
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GXV_KERN_DATA( dialect_request )
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#define KERN_ALLOWS_MS( valid ) \
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( KERN_DIALECT( valid ) & KERN_DIALECT_MS )
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#define KERN_ALLOWS_APPLE( valid ) \
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( KERN_DIALECT( valid ) & KERN_DIALECT_APPLE )
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#define GXV_KERN_HEADER_SIZE ( KERN_IS_NEW( valid ) ? 8 : 4 )
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#define GXV_KERN_SUBTABLE_HEADER_SIZE ( KERN_IS_NEW( valid ) ? 8 : 6 )
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/*************************************************************************/
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/*************************************************************************/
101
/***** SUBTABLE VALIDATORS *****/
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/*************************************************************************/
104
/*************************************************************************/
107
/* ============================= format 0 ============================== */
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gxv_kern_subtable_fmt0_pairs_validate( FT_Bytes table,
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GXV_Validator valid )
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FT_UShort last_gid_left = 0;
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FT_UShort last_gid_right = 0;
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GXV_NAME_ENTER( "kern format 0 pairs" );
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for ( i = 0; i < nPairs; i++ )
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gid_left = FT_NEXT_USHORT( p );
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gxv_glyphid_validate( gid_left, valid );
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gid_right = FT_NEXT_USHORT( p );
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gxv_glyphid_validate( gid_right, valid );
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/* Pairs of left and right GIDs must be unique and sorted. */
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GXV_TRACE(( "left gid = %u, right gid = %u\n", gid_left, gid_right ));
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if ( gid_left == last_gid_left )
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if ( last_gid_right < gid_right )
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last_gid_right = gid_right;
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else if ( last_gid_left < gid_left )
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last_gid_left = gid_left;
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last_gid_right = gid_right;
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/* skip the kern value */
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kernValue = FT_NEXT_SHORT( p );
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gxv_kern_subtable_fmt0_validate( FT_Bytes table,
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GXV_Validator valid )
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FT_Bytes p = table + GXV_KERN_SUBTABLE_HEADER_SIZE;
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GXV_NAME_ENTER( "kern subtable format 0" );
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unitSize = 2 + 2 + 2;
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/* nPairs, searchRange, entrySelector, rangeShift */
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GXV_LIMIT_CHECK( 2 + 2 + 2 + 2 );
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gxv_BinSrchHeader_validate( p, limit, &unitSize, &nPairs, valid );
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gxv_kern_subtable_fmt0_pairs_validate( p, limit, nPairs, valid );
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/* ============================= format 1 ============================== */
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typedef struct GXV_kern_fmt1_StateOptRec_
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FT_UShort valueTable;
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FT_UShort valueTable_length;
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} GXV_kern_fmt1_StateOptRec, *GXV_kern_fmt1_StateOptRecData;
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gxv_kern_subtable_fmt1_valueTable_load( FT_Bytes table,
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GXV_Validator valid )
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GXV_kern_fmt1_StateOptRecData optdata =
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(GXV_kern_fmt1_StateOptRecData)valid->statetable.optdata;
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GXV_LIMIT_CHECK( 2 );
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optdata->valueTable = FT_NEXT_USHORT( p );
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* passed tables_size covers whole StateTable, including kern fmt1 header
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gxv_kern_subtable_fmt1_subtable_setup( FT_UShort table_size,
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FT_UShort classTable,
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FT_UShort stateArray,
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FT_UShort entryTable,
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FT_UShort* classTable_length_p,
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FT_UShort* stateArray_length_p,
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FT_UShort* entryTable_length_p,
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GXV_Validator valid )
235
GXV_kern_fmt1_StateOptRecData optdata =
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(GXV_kern_fmt1_StateOptRecData)valid->statetable.optdata;
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o[3] = optdata->valueTable;
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l[0] = classTable_length_p;
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l[1] = stateArray_length_p;
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l[2] = entryTable_length_p;
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l[3] = &(optdata->valueTable_length);
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gxv_set_length_by_ushort_offset( o, l, buff, 4, table_size, valid );
253
* passed table & limit are of whole StateTable, not including subtables
256
gxv_kern_subtable_fmt1_entry_validate(
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GXV_StateTable_GlyphOffsetDesc glyphOffset,
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GXV_Validator valid )
265
FT_UShort dontAdvance;
266
FT_UShort valueOffset;
267
FT_UShort kernAction;
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FT_UNUSED( glyphOffset );
274
push = (FT_UShort)( ( flags >> 15 ) & 1 );
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dontAdvance = (FT_UShort)( ( flags >> 14 ) & 1 );
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valueOffset = (FT_UShort)( flags & 0x3FFF );
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GXV_kern_fmt1_StateOptRecData vt_rec =
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(GXV_kern_fmt1_StateOptRecData)valid->statetable.optdata;
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if ( valueOffset < vt_rec->valueTable )
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p = table + valueOffset;
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limit = table + vt_rec->valueTable + vt_rec->valueTable_length;
290
GXV_LIMIT_CHECK( 2 + 2 );
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kernAction = FT_NEXT_USHORT( p );
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kernValue = FT_NEXT_USHORT( p );
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gxv_kern_subtable_fmt1_validate( FT_Bytes table,
300
GXV_Validator valid )
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GXV_kern_fmt1_StateOptRec vt_rec;
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GXV_NAME_ENTER( "kern subtable format 1" );
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valid->statetable.optdata =
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valid->statetable.optdata_load_func =
311
gxv_kern_subtable_fmt1_valueTable_load;
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valid->statetable.subtable_setup_func =
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gxv_kern_subtable_fmt1_subtable_setup;
314
valid->statetable.entry_glyphoffset_fmt =
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GXV_GLYPHOFFSET_NONE;
316
valid->statetable.entry_validate_func =
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gxv_kern_subtable_fmt1_entry_validate;
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gxv_StateTable_validate( p, limit, valid );
325
/* ================ Data for Class-Based Subtables 2, 3 ================ */
327
typedef enum GXV_kern_ClassSpec_
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} GXV_kern_ClassSpec;
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/* ============================= format 2 ============================== */
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/* ---------------------- format 2 specific data ----------------------- */
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typedef struct GXV_kern_subtable_fmt2_DataRec_
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FT_UShort offset_min[2];
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FT_UShort offset_max[2];
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const FT_String* class_tag[2];
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GXV_odtect_Range odtect;
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} GXV_kern_subtable_fmt2_DataRec, *GXV_kern_subtable_fmt2_Data;
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#define GXV_KERN_FMT2_DATA( field ) \
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( ( (GXV_kern_subtable_fmt2_DataRec *) \
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( GXV_KERN_DATA( subtable_data ) ) )->field )
356
/* -------------------------- utility functions ----------------------- */
359
gxv_kern_subtable_fmt2_clstbl_validate( FT_Bytes table,
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GXV_kern_ClassSpec spec,
362
GXV_Validator valid )
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const FT_String* tag = GXV_KERN_FMT2_DATA( class_tag[spec] );
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GXV_odtect_Range odtect = GXV_KERN_FMT2_DATA( odtect );
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FT_UShort firstGlyph;
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GXV_NAME_ENTER( "kern format 2 classTable" );
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GXV_LIMIT_CHECK( 2 + 2 );
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firstGlyph = FT_NEXT_USHORT( p );
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nGlyphs = FT_NEXT_USHORT( p );
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GXV_TRACE(( " %s firstGlyph=%d, nGlyphs=%d\n",
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tag, firstGlyph, nGlyphs ));
380
gxv_glyphid_validate( firstGlyph, valid );
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gxv_glyphid_validate( (FT_UShort)( firstGlyph + nGlyphs - 1 ), valid );
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gxv_array_getlimits_ushort( p, p + ( 2 * nGlyphs ),
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&( GXV_KERN_FMT2_DATA( offset_min[spec] ) ),
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&( GXV_KERN_FMT2_DATA( offset_max[spec] ) ),
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gxv_odtect_add_range( table, 2 * nGlyphs, tag, odtect );
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gxv_kern_subtable_fmt2_validate( FT_Bytes table,
397
GXV_Validator valid )
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GXV_ODTECT( 3, odtect );
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GXV_kern_subtable_fmt2_DataRec fmt2_rec =
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{ 0, 0, { 0, 0 }, { 0, 0 }, { "leftClass", "rightClass" }, NULL };
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FT_Bytes p = table + GXV_KERN_SUBTABLE_HEADER_SIZE;
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FT_UShort leftOffsetTable;
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FT_UShort rightOffsetTable;
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GXV_NAME_ENTER( "kern subtable format 2" );
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GXV_ODTECT_INIT( odtect );
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fmt2_rec.odtect = odtect;
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GXV_KERN_DATA( subtable_data ) = &fmt2_rec;
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GXV_LIMIT_CHECK( 2 + 2 + 2 + 2 );
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GXV_KERN_FMT2_DATA( rowWidth ) = FT_NEXT_USHORT( p );
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leftOffsetTable = FT_NEXT_USHORT( p );
417
rightOffsetTable = FT_NEXT_USHORT( p );
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GXV_KERN_FMT2_DATA( array ) = FT_NEXT_USHORT( p );
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GXV_TRACE(( "rowWidth = %d\n", GXV_KERN_FMT2_DATA( rowWidth ) ));
423
GXV_LIMIT_CHECK( leftOffsetTable );
424
GXV_LIMIT_CHECK( rightOffsetTable );
425
GXV_LIMIT_CHECK( GXV_KERN_FMT2_DATA( array ) );
427
gxv_kern_subtable_fmt2_clstbl_validate( table + leftOffsetTable, limit,
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GXV_KERN_CLS_L, valid );
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gxv_kern_subtable_fmt2_clstbl_validate( table + rightOffsetTable, limit,
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GXV_KERN_CLS_R, valid );
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if ( GXV_KERN_FMT2_DATA( offset_min[GXV_KERN_CLS_L] ) +
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GXV_KERN_FMT2_DATA( offset_min[GXV_KERN_CLS_R] )
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< GXV_KERN_FMT2_DATA( array ) )
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gxv_odtect_add_range( table + GXV_KERN_FMT2_DATA( array ),
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GXV_KERN_FMT2_DATA( offset_max[GXV_KERN_CLS_L] )
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+ GXV_KERN_FMT2_DATA( offset_max[GXV_KERN_CLS_R] )
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- GXV_KERN_FMT2_DATA( array ),
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gxv_odtect_validate( odtect, valid );
450
/* ============================= format 3 ============================== */
453
gxv_kern_subtable_fmt3_validate( FT_Bytes table,
455
GXV_Validator valid )
457
FT_Bytes p = table + GXV_KERN_SUBTABLE_HEADER_SIZE;
458
FT_UShort glyphCount;
459
FT_Byte kernValueCount;
460
FT_Byte leftClassCount;
461
FT_Byte rightClassCount;
465
GXV_NAME_ENTER( "kern subtable format 3" );
467
GXV_LIMIT_CHECK( 2 + 1 + 1 + 1 + 1 );
468
glyphCount = FT_NEXT_USHORT( p );
469
kernValueCount = FT_NEXT_BYTE( p );
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leftClassCount = FT_NEXT_BYTE( p );
471
rightClassCount = FT_NEXT_BYTE( p );
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flags = FT_NEXT_BYTE( p );
474
if ( valid->face->num_glyphs != glyphCount )
476
GXV_TRACE(( "maxGID=%d, but glyphCount=%d\n",
477
valid->face->num_glyphs, glyphCount ));
478
if ( valid->root->level >= FT_VALIDATE_PARANOID )
483
* just skip kernValue[kernValueCount]
485
GXV_LIMIT_CHECK( 2 * kernValueCount );
486
p += 2 * kernValueCount;
489
* check leftClass[gid] < leftClassCount
495
GXV_LIMIT_CHECK( glyphCount );
496
gxv_array_getlimits_byte( p, p + glyphCount, &min, &max, valid );
497
p += valid->subtable_length;
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if ( leftClassCount < max )
504
* check rightClass[gid] < rightClassCount
510
GXV_LIMIT_CHECK( glyphCount );
511
gxv_array_getlimits_byte( p, p + glyphCount, &min, &max, valid );
512
p += valid->subtable_length;
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if ( rightClassCount < max )
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* check kernIndex[i, j] < kernValueCount
525
for ( i = 0; i < leftClassCount; i++ )
527
for ( j = 0; j < rightClassCount; j++ )
529
GXV_LIMIT_CHECK( 1 );
530
if ( kernValueCount < FT_NEXT_BYTE( p ) )
536
valid->subtable_length = p - table;
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gxv_kern_coverage_new_apple_validate( FT_UShort coverage,
545
GXV_Validator valid )
547
/* new Apple-dialect */
548
FT_Bool kernVertical;
549
FT_Bool kernCrossStream;
550
FT_Bool kernVariation;
555
/* reserved bits = 0 */
556
if ( coverage & 0x1FFC )
559
kernVertical = FT_BOOL( ( coverage >> 15 ) & 1 );
560
kernCrossStream = FT_BOOL( ( coverage >> 14 ) & 1 );
561
kernVariation = FT_BOOL( ( coverage >> 13 ) & 1 );
563
*format = (FT_UShort)( coverage & 0x0003 );
565
GXV_TRACE(( "new Apple-dialect: "
566
"horizontal=%d, cross-stream=%d, variation=%d, format=%d\n",
567
!kernVertical, kernCrossStream, kernVariation, *format ));
569
GXV_TRACE(( "kerning values in Apple format subtable are ignored\n" ));
576
gxv_kern_coverage_classic_apple_validate( FT_UShort coverage,
578
GXV_Validator valid )
580
/* classic Apple-dialect */
582
FT_Bool cross_stream;
585
/* check expected flags, but don't check if MS-dialect is impossible */
586
if ( !( coverage & 0xFD00 ) && KERN_ALLOWS_MS( valid ) )
589
/* reserved bits = 0 */
590
if ( coverage & 0x02FC )
593
horizontal = FT_BOOL( ( coverage >> 15 ) & 1 );
594
cross_stream = FT_BOOL( ( coverage >> 13 ) & 1 );
596
*format = (FT_UShort)( coverage & 0x0003 );
598
GXV_TRACE(( "classic Apple-dialect: "
599
"horizontal=%d, cross-stream=%d, format=%d\n",
600
horizontal, cross_stream, *format ));
602
/* format 1 requires GX State Machine, too new for classic */
606
GXV_TRACE(( "kerning values in Apple format subtable are ignored\n" ));
613
gxv_kern_coverage_classic_microsoft_validate( FT_UShort coverage,
615
GXV_Validator valid )
617
/* classic Microsoft-dialect */
620
FT_Bool cross_stream;
626
/* reserved bits = 0 */
627
if ( coverage & 0xFDF0 )
630
horizontal = FT_BOOL( coverage & 1 );
631
minimum = FT_BOOL( ( coverage >> 1 ) & 1 );
632
cross_stream = FT_BOOL( ( coverage >> 2 ) & 1 );
633
override = FT_BOOL( ( coverage >> 3 ) & 1 );
635
*format = (FT_UShort)( ( coverage >> 8 ) & 0x0003 );
637
GXV_TRACE(( "classic Microsoft-dialect: "
638
"horizontal=%d, minimum=%d, cross-stream=%d, "
639
"override=%d, format=%d\n",
640
horizontal, minimum, cross_stream, override, *format ));
644
"kerning values in Microsoft format 2 subtable are ignored\n" ));
650
/*************************************************************************/
651
/*************************************************************************/
655
/*************************************************************************/
656
/*************************************************************************/
658
static GXV_kern_Dialect
659
gxv_kern_coverage_validate( FT_UShort coverage,
661
GXV_Validator valid )
663
GXV_kern_Dialect result = KERN_DIALECT_UNKNOWN;
666
GXV_NAME_ENTER( "validating coverage" );
668
GXV_TRACE(( "interprete coverage 0x%04x by Apple style\n", coverage ));
670
if ( KERN_IS_NEW( valid ) )
672
if ( gxv_kern_coverage_new_apple_validate( coverage,
676
result = KERN_DIALECT_APPLE;
681
if ( KERN_IS_CLASSIC( valid ) && KERN_ALLOWS_APPLE( valid ) )
683
if ( gxv_kern_coverage_classic_apple_validate( coverage,
687
result = KERN_DIALECT_APPLE;
692
if ( KERN_IS_CLASSIC( valid ) && KERN_ALLOWS_MS( valid ) )
694
if ( gxv_kern_coverage_classic_microsoft_validate( coverage,
698
result = KERN_DIALECT_MS;
703
GXV_TRACE(( "cannot interprete coverage, broken kern subtable\n" ));
712
gxv_kern_subtable_validate( FT_Bytes table,
714
GXV_Validator valid )
717
FT_UShort version = 0; /* MS only: subtable version, unused */
718
FT_ULong length; /* MS: 16bit, Apple: 32bit*/
720
FT_UShort tupleIndex = 0; /* Apple only */
722
FT_UShort format = 255; /* subtable format */
725
GXV_NAME_ENTER( "kern subtable" );
727
GXV_LIMIT_CHECK( 2 + 2 + 2 );
728
u16[0] = FT_NEXT_USHORT( p ); /* Apple: length_hi MS: version */
729
u16[1] = FT_NEXT_USHORT( p ); /* Apple: length_lo MS: length */
730
coverage = FT_NEXT_USHORT( p );
732
switch ( gxv_kern_coverage_validate( coverage, &format, valid ) )
734
case KERN_DIALECT_MS:
738
GXV_TRACE(( "Subtable version = %d\n", version ));
739
GXV_TRACE(( "Subtable length = %d\n", length ));
742
case KERN_DIALECT_APPLE:
744
length = ( u16[0] << 16 ) + u16[1];
746
GXV_TRACE(( "Subtable length = %d\n", length ));
748
if ( KERN_IS_NEW( valid ) )
750
GXV_LIMIT_CHECK( 2 );
751
tupleIndex = FT_NEXT_USHORT( p );
752
GXV_TRACE(( "Subtable tupleIndex = %d\n", tupleIndex ));
758
GXV_TRACE(( "cannot detect subtable dialect, "
759
"just skip %d byte\n", length ));
763
/* formats 1, 2, 3 require the position of the start of this subtable */
765
gxv_kern_subtable_fmt0_validate( table, table + length, valid );
766
else if ( format == 1 )
767
gxv_kern_subtable_fmt1_validate( table, table + length, valid );
768
else if ( format == 2 )
769
gxv_kern_subtable_fmt2_validate( table, table + length, valid );
770
else if ( format == 3 )
771
gxv_kern_subtable_fmt3_validate( table, table + length, valid );
776
valid->subtable_length = length;
781
/*************************************************************************/
782
/*************************************************************************/
784
/***** kern TABLE *****/
786
/*************************************************************************/
787
/*************************************************************************/
790
gxv_kern_validate_generic( FT_Bytes table,
792
FT_Bool classic_only,
793
GXV_kern_Dialect dialect_request,
794
FT_Validator ftvalid )
796
GXV_ValidatorRec validrec;
797
GXV_Validator valid = &validrec;
799
GXV_kern_DataRec kernrec;
800
GXV_kern_Data kern = &kernrec;
805
FT_ULong nTables = 0;
809
valid->root = ftvalid;
810
valid->table_data = kern;
813
FT_TRACE3(( "validating `kern' table\n" ));
815
KERN_DIALECT( valid ) = dialect_request;
817
GXV_LIMIT_CHECK( 2 );
818
GXV_KERN_DATA( version ) = (GXV_kern_Version)FT_NEXT_USHORT( p );
819
GXV_TRACE(( "version 0x%04x (higher 16bit)\n",
820
GXV_KERN_DATA( version ) ));
822
if ( 0x0001 < GXV_KERN_DATA( version ) )
824
else if ( KERN_IS_CLASSIC( valid ) )
826
GXV_LIMIT_CHECK( 2 );
827
nTables = FT_NEXT_USHORT( p );
829
else if ( KERN_IS_NEW( valid ) )
834
if ( 0x0000 != FT_NEXT_USHORT( p ) )
837
GXV_LIMIT_CHECK( 4 );
838
nTables = FT_NEXT_ULONG( p );
841
for ( i = 0; i < nTables; i++ )
843
GXV_TRACE(( "validating subtable %d/%d\n", i, nTables ));
844
/* p should be 32bit-aligned? */
845
gxv_kern_subtable_validate( p, 0, valid );
846
p += valid->subtable_length;
854
gxv_kern_validate( FT_Bytes table,
856
FT_Validator ftvalid )
858
gxv_kern_validate_generic( table, face, 0, KERN_DIALECT_ANY, ftvalid );
863
gxv_kern_validate_classic( FT_Bytes table,
865
FT_Int dialect_flags,
866
FT_Validator ftvalid )
868
GXV_kern_Dialect dialect_request;
871
dialect_request = (GXV_kern_Dialect)dialect_flags;
872
gxv_kern_validate_generic( table, face, 1, dialect_request, ftvalid );