Edit
kc3-lang/freetype/src/otvalid/otvmath.c
Alexei Podtelezhnikov
- src/otvalid/otvmath.c
-
/**************************************************************************** * * otvmath.c * * OpenType MATH table validation (body). * * Copyright (C) 2007-2024 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 otvmath /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** MATH TYPOGRAPHIC CONSTANTS *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ static void otv_MathConstants_validate( FT_Bytes table, OTV_Validator otvalid ) { 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, otvalid ); } OTV_EXIT; } /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** MATH ITALICS CORRECTION *****/ /***** MATH TOP ACCENT ATTACHMENT *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ static void otv_MathItalicsCorrectionInfo_validate( FT_Bytes table, OTV_Validator otvalid, 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, otvalid, (FT_Int)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, otvalid ); } OTV_EXIT; } /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** MATH KERNING *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ static void otv_MathKern_validate( FT_Bytes table, OTV_Validator otvalid ) { 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, otvalid ); } /* 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, otvalid ); } OTV_EXIT; } static void otv_MathKernInfo_validate( FT_Bytes table, OTV_Validator otvalid ) { 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, otvalid, (FT_Int)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, otvalid ); } } OTV_EXIT; } /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** MATH GLYPH INFO *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ static void otv_MathGlyphInfo_validate( FT_Bytes table, OTV_Validator otvalid ) { 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, otvalid, TRUE ); /* Italic correction and Top Accent Attachment have the same format */ if ( MathTopAccentAttachment ) otv_MathItalicsCorrectionInfo_validate( table + MathTopAccentAttachment, otvalid, FALSE ); if ( ExtendedShapeCoverage ) { OTV_NAME_ENTER( "ExtendedShapeCoverage" ); otv_Coverage_validate( table + ExtendedShapeCoverage, otvalid, -1 ); OTV_EXIT; } if ( MathKernInfo ) otv_MathKernInfo_validate( table + MathKernInfo, otvalid ); OTV_EXIT; } /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** MATH GLYPH CONSTRUCTION *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ static void otv_GlyphAssembly_validate( FT_Bytes table, OTV_Validator otvalid ) { 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, otvalid ); for ( i = 0; i < pcnt; i++ ) { FT_UInt gid; gid = FT_NEXT_USHORT( p ); if ( gid >= otvalid->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 otvalid ) { 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 >= otvalid->glyph_count ) FT_INVALID_GLYPH_ID; p += 2; /* skip the size */ } OTV_SIZE_CHECK( GlyphAssembly ); if ( GlyphAssembly ) otv_GlyphAssembly_validate( table+GlyphAssembly, otvalid ); /* OTV_EXIT; */ } static void otv_MathVariants_validate( FT_Bytes table, OTV_Validator otvalid ) { 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, otvalid, (FT_Int)vcnt ); OTV_SIZE_CHECK( HCoverage ); if ( HCoverage ) otv_Coverage_validate( table + HCoverage, otvalid, (FT_Int)hcnt ); for ( i = 0; i < vcnt; i++ ) { OTV_OPTIONAL_OFFSET( Offset ); OTV_SIZE_CHECK( Offset ); otv_MathGlyphConstruction_validate( table + Offset, otvalid ); } for ( i = 0; i < hcnt; i++ ) { OTV_OPTIONAL_OFFSET( Offset ); OTV_SIZE_CHECK( Offset ); otv_MathGlyphConstruction_validate( table + Offset, otvalid ); } OTV_EXIT; } /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** MATH TABLE *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ /* sets otvalid->glyph_count */ FT_LOCAL_DEF( void ) otv_MATH_validate( FT_Bytes table, FT_UInt glyph_count, FT_Validator ftvalid ) { OTV_ValidatorRec otvalidrec; OTV_Validator otvalid = &otvalidrec; FT_Bytes p = table; FT_UInt MathConstants, MathGlyphInfo, MathVariants; otvalid->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 ); otvalid->glyph_count = glyph_count; otv_MathConstants_validate( table + MathConstants, otvalid ); otv_MathGlyphInfo_validate( table + MathGlyphInfo, otvalid ); otv_MathVariants_validate ( table + MathVariants, otvalid ); FT_TRACE4(( "\n" )); } /* END */