misc/libfreetype/src/otvalid/otvmath.c
changeset 5172 88f2e05288ba
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/misc/libfreetype/src/otvalid/otvmath.c	Mon Apr 25 01:46:54 2011 +0200
@@ -0,0 +1,453 @@
+/***************************************************************************/
+/*                                                                         */
+/*  otvmath.c                                                              */
+/*                                                                         */
+/*    OpenType MATH table validation (body).                               */
+/*                                                                         */
+/*  Copyright 2007, 2008 by                                                */
+/*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
+/*                                                                         */
+/*  Written by George Williams.                                            */
+/*                                                                         */
+/*  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 "otvalid.h"
+#include "otvcommn.h"
+#include "otvgpos.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_otvmath
+
+
+
+  /*************************************************************************/
+  /*************************************************************************/
+  /*****                                                               *****/
+  /*****                  MATH TYPOGRAPHIC CONSTANTS                   *****/
+  /*****                                                               *****/
+  /*************************************************************************/
+  /*************************************************************************/
+
+  static void
+  otv_MathConstants_validate( FT_Bytes       table,
+                              OTV_Validator  valid )
+  {
+    FT_Bytes  p = table;
+    FT_UInt   i;
+    FT_UInt   table_size;
+
+    OTV_OPTIONAL_TABLE( DeviceTableOffset );
+
+
+    OTV_NAME_ENTER( "MathConstants" );
+
+    /* 56 constants, 51 have device tables */
+    OTV_LIMIT_CHECK( 2 * ( 56 + 51 ) );
+    table_size = 2 * ( 56 + 51 );
+
+    p += 4 * 2;                 /* First 4 constants have no device tables */
+    for ( i = 0; i < 51; ++i )
+    {
+      p += 2;                                            /* skip the value */
+      OTV_OPTIONAL_OFFSET( DeviceTableOffset );
+      OTV_SIZE_CHECK( DeviceTableOffset );
+      if ( DeviceTableOffset )
+        otv_Device_validate( table + DeviceTableOffset, valid );
+    }
+
+    OTV_EXIT;
+  }
+
+
+  /*************************************************************************/
+  /*************************************************************************/
+  /*****                                                               *****/
+  /*****                   MATH ITALICS CORRECTION                     *****/
+  /*****                 MATH TOP ACCENT ATTACHMENT                    *****/
+  /*****                                                               *****/
+  /*************************************************************************/
+  /*************************************************************************/
+
+  static void
+  otv_MathItalicsCorrectionInfo_validate( FT_Bytes       table,
+                                          OTV_Validator  valid,
+                                          FT_Int         isItalic )
+  {
+    FT_Bytes  p = table;
+    FT_UInt   i, cnt, table_size ;
+
+    OTV_OPTIONAL_TABLE( Coverage );
+    OTV_OPTIONAL_TABLE( DeviceTableOffset );
+
+    FT_UNUSED( isItalic );  /* only used if tracing is active */
+
+
+    OTV_NAME_ENTER( isItalic ? "MathItalicsCorrectionInfo"
+                             : "MathTopAccentAttachment" );
+
+    OTV_LIMIT_CHECK( 4 );
+
+    OTV_OPTIONAL_OFFSET( Coverage );
+    cnt = FT_NEXT_USHORT( p );
+
+    OTV_LIMIT_CHECK( 4 * cnt );
+    table_size = 4 + 4 * cnt;
+
+    OTV_SIZE_CHECK( Coverage );
+    otv_Coverage_validate( table + Coverage, valid, cnt );
+
+    for ( i = 0; i < cnt; ++i )
+    {
+      p += 2;                                            /* Skip the value */
+      OTV_OPTIONAL_OFFSET( DeviceTableOffset );
+      OTV_SIZE_CHECK( DeviceTableOffset );
+      if ( DeviceTableOffset )
+        otv_Device_validate( table + DeviceTableOffset, valid );
+    }
+
+    OTV_EXIT;
+  }
+
+
+  /*************************************************************************/
+  /*************************************************************************/
+  /*****                                                               *****/
+  /*****                           MATH KERNING                        *****/
+  /*****                                                               *****/
+  /*************************************************************************/
+  /*************************************************************************/
+
+  static void
+  otv_MathKern_validate( FT_Bytes       table,
+                         OTV_Validator  valid )
+  {
+    FT_Bytes  p = table;
+    FT_UInt   i, cnt, table_size;
+
+    OTV_OPTIONAL_TABLE( DeviceTableOffset );
+
+
+    /* OTV_NAME_ENTER( "MathKern" );*/
+
+    OTV_LIMIT_CHECK( 2 );
+
+    cnt = FT_NEXT_USHORT( p );
+
+    OTV_LIMIT_CHECK( 4 * cnt + 2 );
+    table_size = 4 + 4 * cnt;
+
+    /* Heights */
+    for ( i = 0; i < cnt; ++i )
+    {
+      p += 2;                                            /* Skip the value */
+      OTV_OPTIONAL_OFFSET( DeviceTableOffset );
+      OTV_SIZE_CHECK( DeviceTableOffset );
+      if ( DeviceTableOffset )
+        otv_Device_validate( table + DeviceTableOffset, valid );
+    }
+
+    /* One more Kerning value */
+    for ( i = 0; i < cnt + 1; ++i )
+    {
+      p += 2;                                            /* Skip the value */
+      OTV_OPTIONAL_OFFSET( DeviceTableOffset );
+      OTV_SIZE_CHECK( DeviceTableOffset );
+      if ( DeviceTableOffset )
+        otv_Device_validate( table + DeviceTableOffset, valid );
+    }
+
+    OTV_EXIT;
+  }
+
+
+  static void
+  otv_MathKernInfo_validate( FT_Bytes       table,
+                             OTV_Validator  valid )
+  {
+    FT_Bytes  p = table;
+    FT_UInt   i, j, cnt, table_size;
+
+    OTV_OPTIONAL_TABLE( Coverage );
+    OTV_OPTIONAL_TABLE( MKRecordOffset );
+
+
+    OTV_NAME_ENTER( "MathKernInfo" );
+
+    OTV_LIMIT_CHECK( 4 );
+
+    OTV_OPTIONAL_OFFSET( Coverage );
+    cnt = FT_NEXT_USHORT( p );
+
+    OTV_LIMIT_CHECK( 8 * cnt );
+    table_size = 4 + 8 * cnt;
+
+    OTV_SIZE_CHECK( Coverage );
+    otv_Coverage_validate( table + Coverage, valid, cnt );
+
+    for ( i = 0; i < cnt; ++i )
+    {
+      for ( j = 0; j < 4; ++j )
+      {
+        OTV_OPTIONAL_OFFSET( MKRecordOffset );
+        OTV_SIZE_CHECK( MKRecordOffset );
+        if ( MKRecordOffset )
+          otv_MathKern_validate( table + MKRecordOffset, valid );
+      }
+    }
+
+    OTV_EXIT;
+  }
+
+
+  /*************************************************************************/
+  /*************************************************************************/
+  /*****                                                               *****/
+  /*****                         MATH GLYPH INFO                       *****/
+  /*****                                                               *****/
+  /*************************************************************************/
+  /*************************************************************************/
+
+  static void
+  otv_MathGlyphInfo_validate( FT_Bytes       table,
+                              OTV_Validator  valid )
+  {
+    FT_Bytes  p = table;
+    FT_UInt   MathItalicsCorrectionInfo, MathTopAccentAttachment;
+    FT_UInt   ExtendedShapeCoverage, MathKernInfo;
+
+
+    OTV_NAME_ENTER( "MathGlyphInfo" );
+
+    OTV_LIMIT_CHECK( 8 );
+
+    MathItalicsCorrectionInfo = FT_NEXT_USHORT( p );
+    MathTopAccentAttachment   = FT_NEXT_USHORT( p );
+    ExtendedShapeCoverage     = FT_NEXT_USHORT( p );
+    MathKernInfo              = FT_NEXT_USHORT( p );
+
+    if ( MathItalicsCorrectionInfo )
+      otv_MathItalicsCorrectionInfo_validate(
+        table + MathItalicsCorrectionInfo, valid, TRUE );
+
+    /* Italic correction and Top Accent Attachment have the same format */
+    if ( MathTopAccentAttachment )
+      otv_MathItalicsCorrectionInfo_validate(
+        table + MathTopAccentAttachment, valid, FALSE );
+
+    if ( ExtendedShapeCoverage )
+    {
+      OTV_NAME_ENTER( "ExtendedShapeCoverage" );
+      otv_Coverage_validate( table + ExtendedShapeCoverage, valid, -1 );
+      OTV_EXIT;
+    }
+
+    if ( MathKernInfo )
+      otv_MathKernInfo_validate( table + MathKernInfo, valid );
+
+    OTV_EXIT;
+  }
+
+
+  /*************************************************************************/
+  /*************************************************************************/
+  /*****                                                               *****/
+  /*****                    MATH GLYPH CONSTRUCTION                    *****/
+  /*****                                                               *****/
+  /*************************************************************************/
+  /*************************************************************************/
+
+  static void
+  otv_GlyphAssembly_validate( FT_Bytes       table,
+                              OTV_Validator  valid )
+  {
+    FT_Bytes  p = table;
+    FT_UInt   pcnt, table_size;
+    FT_UInt   i;
+
+    OTV_OPTIONAL_TABLE( DeviceTableOffset );
+
+
+    /* OTV_NAME_ENTER( "GlyphAssembly" ); */
+
+    OTV_LIMIT_CHECK( 6 );
+
+    p += 2;                           /* Skip the Italics Correction value */
+    OTV_OPTIONAL_OFFSET( DeviceTableOffset );
+    pcnt = FT_NEXT_USHORT( p );
+
+    OTV_LIMIT_CHECK( 8 * pcnt );
+    table_size = 6 + 8 * pcnt;
+
+    OTV_SIZE_CHECK( DeviceTableOffset );
+    if ( DeviceTableOffset )
+      otv_Device_validate( table + DeviceTableOffset, valid );
+
+    for ( i = 0; i < pcnt; ++i )
+    {
+      FT_UInt  gid;
+
+
+      gid = FT_NEXT_USHORT( p );
+      if ( gid >= valid->glyph_count )
+        FT_INVALID_GLYPH_ID;
+      p += 2*4;             /* skip the Start, End, Full, and Flags fields */
+    }
+
+    /* OTV_EXIT; */
+  }
+
+
+  static void
+  otv_MathGlyphConstruction_validate( FT_Bytes       table,
+                                      OTV_Validator  valid )
+  {
+    FT_Bytes  p = table;
+    FT_UInt   vcnt, table_size;
+    FT_UInt   i;
+
+    OTV_OPTIONAL_TABLE( GlyphAssembly );
+
+
+    /* OTV_NAME_ENTER( "MathGlyphConstruction" ); */
+
+    OTV_LIMIT_CHECK( 4 );
+
+    OTV_OPTIONAL_OFFSET( GlyphAssembly );
+    vcnt = FT_NEXT_USHORT( p );
+
+    OTV_LIMIT_CHECK( 4 * vcnt );
+    table_size = 4 + 4 * vcnt;
+
+    for ( i = 0; i < vcnt; ++i )
+    {
+      FT_UInt  gid;
+
+
+      gid = FT_NEXT_USHORT( p );
+      if ( gid >= valid->glyph_count )
+        FT_INVALID_GLYPH_ID;
+      p += 2;                          /* skip the size */
+    }
+
+    OTV_SIZE_CHECK( GlyphAssembly );
+    if ( GlyphAssembly )
+      otv_GlyphAssembly_validate( table+GlyphAssembly, valid );
+
+    /* OTV_EXIT; */
+  }
+
+
+  static void
+  otv_MathVariants_validate( FT_Bytes       table,
+                             OTV_Validator  valid )
+  {
+    FT_Bytes  p = table;
+    FT_UInt   vcnt, hcnt, i, table_size;
+
+    OTV_OPTIONAL_TABLE( VCoverage );
+    OTV_OPTIONAL_TABLE( HCoverage );
+    OTV_OPTIONAL_TABLE( Offset );
+
+
+    OTV_NAME_ENTER( "MathVariants" );
+
+    OTV_LIMIT_CHECK( 10 );
+
+    p += 2;                       /* Skip the MinConnectorOverlap constant */
+    OTV_OPTIONAL_OFFSET( VCoverage );
+    OTV_OPTIONAL_OFFSET( HCoverage );
+    vcnt = FT_NEXT_USHORT( p );
+    hcnt = FT_NEXT_USHORT( p );
+
+    OTV_LIMIT_CHECK( 2 * vcnt + 2 * hcnt );
+    table_size = 10 + 2 * vcnt + 2 * hcnt;
+
+    OTV_SIZE_CHECK( VCoverage );
+    if ( VCoverage )
+      otv_Coverage_validate( table + VCoverage, valid, vcnt );
+
+    OTV_SIZE_CHECK( HCoverage );
+    if ( HCoverage )
+      otv_Coverage_validate( table + HCoverage, valid, hcnt );
+
+    for ( i = 0; i < vcnt; ++i )
+    {
+      OTV_OPTIONAL_OFFSET( Offset );
+      OTV_SIZE_CHECK( Offset );
+      otv_MathGlyphConstruction_validate( table + Offset, valid );
+    }
+
+    for ( i = 0; i < hcnt; ++i )
+    {
+      OTV_OPTIONAL_OFFSET( Offset );
+      OTV_SIZE_CHECK( Offset );
+      otv_MathGlyphConstruction_validate( table + Offset, valid );
+    }
+
+    OTV_EXIT;
+  }
+
+
+  /*************************************************************************/
+  /*************************************************************************/
+  /*****                                                               *****/
+  /*****                          MATH TABLE                           *****/
+  /*****                                                               *****/
+  /*************************************************************************/
+  /*************************************************************************/
+
+  /* sets valid->glyph_count */
+
+  FT_LOCAL_DEF( void )
+  otv_MATH_validate( FT_Bytes      table,
+                     FT_UInt       glyph_count,
+                     FT_Validator  ftvalid )
+  {
+    OTV_ValidatorRec  validrec;
+    OTV_Validator     valid = &validrec;
+    FT_Bytes          p     = table;
+    FT_UInt           MathConstants, MathGlyphInfo, MathVariants;
+
+
+    valid->root = ftvalid;
+
+    FT_TRACE3(( "validating MATH table\n" ));
+    OTV_INIT;
+
+    OTV_LIMIT_CHECK( 10 );
+
+    if ( FT_NEXT_ULONG( p ) != 0x10000UL )      /* Version */
+      FT_INVALID_FORMAT;
+
+    MathConstants = FT_NEXT_USHORT( p );
+    MathGlyphInfo = FT_NEXT_USHORT( p );
+    MathVariants  = FT_NEXT_USHORT( p );
+
+    valid->glyph_count = glyph_count;
+
+    otv_MathConstants_validate( table + MathConstants,
+                                valid );
+    otv_MathGlyphInfo_validate( table + MathGlyphInfo,
+                                valid );
+    otv_MathVariants_validate ( table + MathVariants,
+                                valid );
+
+    FT_TRACE4(( "\n" ));
+  }
+
+
+/* END */