workbench/libs/freetype/src/gxvalid/gxvmorx.c

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  gxvmorx.c                                                              */
   4 /*                                                                         */
   5 /*    TrueTypeGX/AAT morx table validation (body).                         */
   6 /*                                                                         */
   7 /*  Copyright 2005, 2008, 2013 by                                          */
   8 /*  suzuki toshiya, Masatake YAMATO, Red Hat K.K.,                         */
   9 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
  10 /*                                                                         */
  11 /*  This file is part of the FreeType project, and may only be used,       */
  12 /*  modified, and distributed under the terms of the FreeType project      */
  13 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
  14 /*  this file you indicate that you have read the license and              */
  15 /*  understand and accept it fully.                                        */
  16 /*                                                                         */
  17 /***************************************************************************/
  18
  19 /***************************************************************************/
  20 /*                                                                         */
  21 /* gxvalid is derived from both gxlayout module and otvalid module.        */
  22 /* Development of gxlayout is supported by the Information-technology      */
  23 /* Promotion Agency(IPA), Japan.                                           */
  24 /*                                                                         */
  25 /***************************************************************************/
  26
  27
  28 #include "gxvmorx.h"
  29
  30
  31   /*************************************************************************/
  32   /*                                                                       */
  33   /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
  34   /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
  35   /* messages during execution.                                            */
  36   /*                                                                       */
  37 #undef  FT_COMPONENT
  38 #define FT_COMPONENT  trace_gxvmorx
  39
  40
  41   static void
  42   gxv_morx_subtables_validate( FT_Bytes       table,
  43                                FT_Bytes       limit,
  44                                FT_UShort      nSubtables,
  45                                GXV_Validator  valid )
  46   {
  47     FT_Bytes  p = table;
  48
  49     GXV_Validate_Func fmt_funcs_table[] =
  50     {
  51       gxv_morx_subtable_type0_validate, /* 0 */
  52       gxv_morx_subtable_type1_validate, /* 1 */
  53       gxv_morx_subtable_type2_validate, /* 2 */
  54       NULL,                             /* 3 */
  55       gxv_morx_subtable_type4_validate, /* 4 */
  56       gxv_morx_subtable_type5_validate, /* 5 */
  57
  58     };
  59
  60     FT_UShort  i;
  61
  62
  63     GXV_NAME_ENTER( "subtables in a chain" );
  64
  65     for ( i = 0; i < nSubtables; i++ )
  66     {
  67       GXV_Validate_Func  func;
  68
  69       FT_ULong  length;
  70       FT_ULong  coverage;
  71 #ifdef GXV_LOAD_UNUSED_VARS
  72       FT_ULong  subFeatureFlags;
  73 #endif
  74       FT_ULong  type;
  75       FT_ULong  rest;
  76
  77
  78       GXV_LIMIT_CHECK( 4 + 4 + 4 );
  79       length          = FT_NEXT_ULONG( p );
  80       coverage        = FT_NEXT_ULONG( p );
  81 #ifdef GXV_LOAD_UNUSED_VARS
  82       subFeatureFlags = FT_NEXT_ULONG( p );
  83 #else
  84       p += 4;
  85 #endif
  86
  87       GXV_TRACE(( "validating chain subtable %d/%d (%d bytes)\n",
  88                   i + 1, nSubtables, length ));
  89
  90       type = coverage & 0x0007;
  91       rest = length - ( 4 + 4 + 4 );
  92       GXV_LIMIT_CHECK( rest );
  93
  94       /* morx coverage consists of mort_coverage & 16bit padding */
  95       gxv_mort_coverage_validate( (FT_UShort)( ( coverage >> 16 ) | coverage ),
  96                                   valid );
  97       if ( type > 5 )
  98         FT_INVALID_FORMAT;
  99
 100       func = fmt_funcs_table[type];
 101       if ( func == NULL )
 102         GXV_TRACE(( "morx type %d is reserved\n", type ));
 103
 104       func( p, p + rest, valid );
 105
 106       /* TODO: subFeatureFlags should be unique in a table? */
 107       p += rest;
 108     }
 109
 110     valid->subtable_length = p - table;
 111
 112     GXV_EXIT;
 113   }
 114
 115
 116   static void
 117   gxv_morx_chain_validate( FT_Bytes       table,
 118                            FT_Bytes       limit,
 119                            GXV_Validator  valid )
 120   {
 121     FT_Bytes  p = table;
 122 #ifdef GXV_LOAD_UNUSED_VARS
 123     FT_ULong  defaultFlags;
 124 #endif
 125     FT_ULong  chainLength;
 126     FT_ULong  nFeatureFlags;
 127     FT_ULong  nSubtables;
 128
 129
 130     GXV_NAME_ENTER( "morx chain header" );
 131
 132     GXV_LIMIT_CHECK( 4 + 4 + 4 + 4 );
 133 #ifdef GXV_LOAD_UNUSED_VARS
 134     defaultFlags  = FT_NEXT_ULONG( p );
 135 #else
 136     p += 4;
 137 #endif
 138     chainLength   = FT_NEXT_ULONG( p );
 139     nFeatureFlags = FT_NEXT_ULONG( p );
 140     nSubtables    = FT_NEXT_ULONG( p );
 141
 142     /* feature-array of morx is same with that of mort */
 143     gxv_mort_featurearray_validate( p, limit, nFeatureFlags, valid );
 144     p += valid->subtable_length;
 145
 146     if ( nSubtables >= 0x10000L )
 147       FT_INVALID_DATA;
 148
 149     gxv_morx_subtables_validate( p, table + chainLength,
 150                                  (FT_UShort)nSubtables, valid );
 151
 152     valid->subtable_length = chainLength;
 153
 154     /* TODO: defaultFlags should be compared with the flags in tables */
 155
 156     GXV_EXIT;
 157   }
 158
 159
 160   FT_LOCAL_DEF( void )
 161   gxv_morx_validate( FT_Bytes      table,
 162                      FT_Face       face,
 163                      FT_Validator  ftvalid )
 164   {
 165     GXV_ValidatorRec  validrec;
 166     GXV_Validator     valid = &validrec;
 167     FT_Bytes          p     = table;
 168     FT_Bytes          limit = 0;
 169     FT_ULong          version;
 170     FT_ULong          nChains;
 171     FT_ULong          i;
 172
 173
 174     valid->root = ftvalid;
 175     valid->face = face;
 176
 177     FT_TRACE3(( "validating `morx' table\n" ));
 178     GXV_INIT;
 179
 180     GXV_LIMIT_CHECK( 4 + 4 );
 181     version = FT_NEXT_ULONG( p );
 182     nChains = FT_NEXT_ULONG( p );
 183
 184     if ( version != 0x00020000UL )
 185       FT_INVALID_FORMAT;
 186
 187     for ( i = 0; i < nChains; i++ )
 188     {
 189       GXV_TRACE(( "validating chain %d/%d\n", i + 1, nChains ));
 190       GXV_32BIT_ALIGNMENT_VALIDATE( p - table );
 191       gxv_morx_chain_validate( p, limit, valid );
 192       p += valid->subtable_length;
 193     }
 194
 195     FT_TRACE4(( "\n" ));
 196   }
 197
 198
 199 /* END */