/******************************************************************* * * ftxgsub.c * * TrueType Open GSUB table support. * * 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. * ******************************************************************/ /* XXX There is *a lot* of duplicated code (cf. formats 5 and 6), but I don't care currently. I believe that it would be possible to save about 50% of TTO code by carefully designing the structures, sharing as much as possible with extensive use of macros. This is something for a volunteer :-) */ #define EXPORT_FUNC #include "ftxopen.h" #include "ftxopenf.h" #include "ftglue.h" #include FT_TRUETYPE_TAGS_H #define GSUB_ID Build_Extension_ID( 'G', 'S', 'U', 'B' ) static FT_Error GSub_Do_Glyph_Lookup( TTO_GSUBHeader* gsub, FT_UShort lookup_index, OTL_Buffer buffer, FT_UShort context_length, int nesting_level ); /********************** * Auxiliary functions **********************/ EXPORT_FUNC FT_Error TT_Load_GSUB_Table( FT_Face face, TTO_GSUBHeader** retptr, TTO_GDEFHeader* gdef ) { FT_Stream stream = face->stream; FT_Memory memory = face->memory; FT_Error error; FT_ULong cur_offset, new_offset, base_offset; FT_UShort i, num_lookups; TTO_GSUBHeader* gsub; TTO_Lookup* lo; if ( !retptr ) return TT_Err_Invalid_Argument; if (( error = ftglue_face_goto_table( face, TTAG_GSUB, stream ) )) return error; base_offset = FILE_Pos(); if ( ALLOC ( gsub, sizeof( *gsub ) ) ) return error; gsub->memory = memory; /* skip version */ if ( FILE_Seek( base_offset + 4L ) || ACCESS_Frame( 2L ) ) goto Fail4; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_ScriptList( &gsub->ScriptList, stream ) ) != TT_Err_Ok ) goto Fail4; (void)FILE_Seek( cur_offset ); if ( ACCESS_Frame( 2L ) ) goto Fail3; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_FeatureList( &gsub->FeatureList, stream ) ) != TT_Err_Ok ) goto Fail3; (void)FILE_Seek( cur_offset ); if ( ACCESS_Frame( 2L ) ) goto Fail2; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_LookupList( &gsub->LookupList, stream, GSUB ) ) != TT_Err_Ok ) goto Fail2; gsub->gdef = gdef; /* can be NULL */ /* We now check the LookupFlags for values larger than 0xFF to find out whether we need to load the `MarkAttachClassDef' field of the GDEF table -- this hack is necessary for OpenType 1.2 tables since the version field of the GDEF table hasn't been incremented. For constructed GDEF tables, we only load it if `MarkAttachClassDef_offset' is not zero (nevertheless, a build of a constructed mark attach table is not supported currently). */ if ( gdef && gdef->MarkAttachClassDef_offset && !gdef->MarkAttachClassDef.loaded ) { lo = gsub->LookupList.Lookup; num_lookups = gsub->LookupList.LookupCount; for ( i = 0; i < num_lookups; i++ ) { if ( lo[i].LookupFlag & IGNORE_SPECIAL_MARKS ) { if ( FILE_Seek( gdef->MarkAttachClassDef_offset ) || ( error = Load_ClassDefinition( &gdef->MarkAttachClassDef, 256, stream ) ) != TT_Err_Ok ) goto Fail1; break; } } } *retptr = gsub; return TT_Err_Ok; Fail1: Free_LookupList( &gsub->LookupList, GSUB, memory ); Fail2: Free_FeatureList( &gsub->FeatureList, memory ); Fail3: Free_ScriptList( &gsub->ScriptList, memory ); Fail4: FREE ( gsub ); return error; } EXPORT_FUNC FT_Error TT_Done_GSUB_Table( TTO_GSUBHeader* gsub ) { FT_Memory memory = gsub->memory; Free_LookupList( &gsub->LookupList, GSUB, memory ); Free_FeatureList( &gsub->FeatureList, memory ); Free_ScriptList( &gsub->ScriptList, memory ); FREE( gsub ); return TT_Err_Ok; } /***************************** * SubTable related functions *****************************/ /* LookupType 1 */ /* SingleSubstFormat1 */ /* SingleSubstFormat2 */ FT_Error Load_SingleSubst( TTO_SingleSubst* ss, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n, count; FT_ULong cur_offset, new_offset, base_offset; FT_UShort* s; base_offset = FILE_Pos(); if ( ACCESS_Frame( 4L ) ) return error; ss->SubstFormat = GET_UShort(); new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_Coverage( &ss->Coverage, stream ) ) != TT_Err_Ok ) return error; (void)FILE_Seek( cur_offset ); switch ( ss->SubstFormat ) { case 1: if ( ACCESS_Frame( 2L ) ) goto Fail2; ss->ssf.ssf1.DeltaGlyphID = GET_UShort(); FORGET_Frame(); break; case 2: if ( ACCESS_Frame( 2L ) ) goto Fail2; count = ss->ssf.ssf2.GlyphCount = GET_UShort(); FORGET_Frame(); ss->ssf.ssf2.Substitute = NULL; if ( ALLOC_ARRAY( ss->ssf.ssf2.Substitute, count, FT_UShort ) ) goto Fail2; s = ss->ssf.ssf2.Substitute; if ( ACCESS_Frame( count * 2L ) ) goto Fail1; for ( n = 0; n < count; n++ ) s[n] = GET_UShort(); FORGET_Frame(); break; default: return TTO_Err_Invalid_GSUB_SubTable_Format; } return TT_Err_Ok; Fail1: FREE( s ); Fail2: Free_Coverage( &ss->Coverage, memory ); return error; } void Free_SingleSubst( TTO_SingleSubst* ss, FT_Memory memory ) { switch ( ss->SubstFormat ) { case 1: break; case 2: FREE( ss->ssf.ssf2.Substitute ); break; } Free_Coverage( &ss->Coverage, memory ); } static FT_Error Lookup_SingleSubst( TTO_SingleSubst* ss, OTL_Buffer buffer, FT_UShort flags, FT_UShort context_length, TTO_GDEFHeader* gdef ) { FT_UShort index, value, property; FT_Error error; if ( context_length != 0xFFFF && context_length < 1 ) return TTO_Err_Not_Covered; if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) ) return error; error = Coverage_Index( &ss->Coverage, IN_CURGLYPH(), &index ); if ( error ) return error; switch ( ss->SubstFormat ) { case 1: value = ( IN_CURGLYPH() + ss->ssf.ssf1.DeltaGlyphID ) & 0xFFFF; if ( ADD_Glyph( buffer, value, 0xFFFF, 0xFFFF ) ) return error; break; case 2: if ( index >= ss->ssf.ssf2.GlyphCount ) return TTO_Err_Invalid_GSUB_SubTable; value = ss->ssf.ssf2.Substitute[index]; if ( ADD_Glyph( buffer, value, 0xFFFF, 0xFFFF ) ) return error; break; default: return TTO_Err_Invalid_GSUB_SubTable; } if ( gdef && gdef->NewGlyphClasses ) { /* we inherit the old glyph class to the substituted glyph */ error = Add_Glyph_Property( gdef, value, property ); if ( error && error != TTO_Err_Not_Covered ) return error; } return TT_Err_Ok; } /* LookupType 2 */ /* Sequence */ static FT_Error Load_Sequence( TTO_Sequence* s, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n, count; FT_UShort* sub; if ( ACCESS_Frame( 2L ) ) return error; count = s->GlyphCount = GET_UShort(); FORGET_Frame(); s->Substitute = NULL; if ( count ) { if ( ALLOC_ARRAY( s->Substitute, count, FT_UShort ) ) return error; sub = s->Substitute; if ( ACCESS_Frame( count * 2L ) ) { FREE( sub ); return error; } for ( n = 0; n < count; n++ ) sub[n] = GET_UShort(); FORGET_Frame(); } return TT_Err_Ok; } static void Free_Sequence( TTO_Sequence* s, FT_Memory memory ) { FREE( s->Substitute ); } /* MultipleSubstFormat1 */ FT_Error Load_MultipleSubst( TTO_MultipleSubst* ms, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n = 0, m, count; FT_ULong cur_offset, new_offset, base_offset; TTO_Sequence* s; base_offset = FILE_Pos(); if ( ACCESS_Frame( 4L ) ) return error; ms->SubstFormat = GET_UShort(); /* should be 1 */ new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_Coverage( &ms->Coverage, stream ) ) != TT_Err_Ok ) return error; (void)FILE_Seek( cur_offset ); if ( ACCESS_Frame( 2L ) ) goto Fail2; count = ms->SequenceCount = GET_UShort(); FORGET_Frame(); ms->Sequence = NULL; if ( ALLOC_ARRAY( ms->Sequence, count, TTO_Sequence ) ) goto Fail2; s = ms->Sequence; for ( n = 0; n < count; n++ ) { if ( ACCESS_Frame( 2L ) ) goto Fail1; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_Sequence( &s[n], stream ) ) != TT_Err_Ok ) goto Fail1; (void)FILE_Seek( cur_offset ); } return TT_Err_Ok; Fail1: for ( m = 0; m < n; m++ ) Free_Sequence( &s[m], memory ); FREE( s ); Fail2: Free_Coverage( &ms->Coverage, memory ); return error; } void Free_MultipleSubst( TTO_MultipleSubst* ms, FT_Memory memory ) { FT_UShort n, count; TTO_Sequence* s; if ( ms->Sequence ) { count = ms->SequenceCount; s = ms->Sequence; for ( n = 0; n < count; n++ ) Free_Sequence( &s[n], memory ); FREE( s ); } Free_Coverage( &ms->Coverage, memory ); } static FT_Error Lookup_MultipleSubst( TTO_MultipleSubst* ms, OTL_Buffer buffer, FT_UShort flags, FT_UShort context_length, TTO_GDEFHeader* gdef ) { FT_Error error; FT_UShort index, property, n, count; FT_UShort*s; if ( context_length != 0xFFFF && context_length < 1 ) return TTO_Err_Not_Covered; if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) ) return error; error = Coverage_Index( &ms->Coverage, IN_CURGLYPH(), &index ); if ( error ) return error; if ( index >= ms->SequenceCount ) return TTO_Err_Invalid_GSUB_SubTable; count = ms->Sequence[index].GlyphCount; s = ms->Sequence[index].Substitute; if ( ADD_String( buffer, 1, count, s, 0xFFFF, 0xFFFF ) ) return error; if ( gdef && gdef->NewGlyphClasses ) { /* this is a guess only ... */ if ( property == TTO_LIGATURE ) property = TTO_BASE_GLYPH; for ( n = 0; n < count; n++ ) { error = Add_Glyph_Property( gdef, s[n], property ); if ( error && error != TTO_Err_Not_Covered ) return error; } } return TT_Err_Ok; } /* LookupType 3 */ /* AlternateSet */ static FT_Error Load_AlternateSet( TTO_AlternateSet* as, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n, count; FT_UShort* a; if ( ACCESS_Frame( 2L ) ) return error; count = as->GlyphCount = GET_UShort(); FORGET_Frame(); as->Alternate = NULL; if ( ALLOC_ARRAY( as->Alternate, count, FT_UShort ) ) return error; a = as->Alternate; if ( ACCESS_Frame( count * 2L ) ) { FREE( a ); return error; } for ( n = 0; n < count; n++ ) a[n] = GET_UShort(); FORGET_Frame(); return TT_Err_Ok; } static void Free_AlternateSet( TTO_AlternateSet* as, FT_Memory memory ) { FREE( as->Alternate ); } /* AlternateSubstFormat1 */ FT_Error Load_AlternateSubst( TTO_AlternateSubst* as, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n = 0, m, count; FT_ULong cur_offset, new_offset, base_offset; TTO_AlternateSet* aset; base_offset = FILE_Pos(); if ( ACCESS_Frame( 4L ) ) return error; as->SubstFormat = GET_UShort(); /* should be 1 */ new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_Coverage( &as->Coverage, stream ) ) != TT_Err_Ok ) return error; (void)FILE_Seek( cur_offset ); if ( ACCESS_Frame( 2L ) ) goto Fail2; count = as->AlternateSetCount = GET_UShort(); FORGET_Frame(); as->AlternateSet = NULL; if ( ALLOC_ARRAY( as->AlternateSet, count, TTO_AlternateSet ) ) goto Fail2; aset = as->AlternateSet; for ( n = 0; n < count; n++ ) { if ( ACCESS_Frame( 2L ) ) goto Fail1; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_AlternateSet( &aset[n], stream ) ) != TT_Err_Ok ) goto Fail1; (void)FILE_Seek( cur_offset ); } return TT_Err_Ok; Fail1: for ( m = 0; m < n; m++ ) Free_AlternateSet( &aset[m], memory ); FREE( aset ); Fail2: Free_Coverage( &as->Coverage, memory ); return error; } void Free_AlternateSubst( TTO_AlternateSubst* as, FT_Memory memory ) { FT_UShort n, count; TTO_AlternateSet* aset; if ( as->AlternateSet ) { count = as->AlternateSetCount; aset = as->AlternateSet; for ( n = 0; n < count; n++ ) Free_AlternateSet( &aset[n], memory ); FREE( aset ); } Free_Coverage( &as->Coverage, memory ); } static FT_Error Lookup_AlternateSubst( TTO_GSUBHeader* gsub, TTO_AlternateSubst* as, OTL_Buffer buffer, FT_UShort flags, FT_UShort context_length, TTO_GDEFHeader* gdef ) { FT_Error error; FT_UShort index, alt_index, property; TTO_AlternateSet aset; if ( context_length != 0xFFFF && context_length < 1 ) return TTO_Err_Not_Covered; if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) ) return error; error = Coverage_Index( &as->Coverage, IN_CURGLYPH(), &index ); if ( error ) return error; aset = as->AlternateSet[index]; /* we use a user-defined callback function to get the alternate index */ if ( gsub->altfunc ) alt_index = (gsub->altfunc)( buffer->out_pos, IN_CURGLYPH(), aset.GlyphCount, aset.Alternate, gsub->data ); else alt_index = 0; if ( ADD_Glyph( buffer, aset.Alternate[alt_index], 0xFFFF, 0xFFFF ) ) return error; if ( gdef && gdef->NewGlyphClasses ) { /* we inherit the old glyph class to the substituted glyph */ error = Add_Glyph_Property( gdef, aset.Alternate[alt_index], property ); if ( error && error != TTO_Err_Not_Covered ) return error; } return TT_Err_Ok; } /* LookupType 4 */ /* Ligature */ static FT_Error Load_Ligature( TTO_Ligature* l, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n, count; FT_UShort* c; if ( ACCESS_Frame( 4L ) ) return error; l->LigGlyph = GET_UShort(); l->ComponentCount = GET_UShort(); FORGET_Frame(); l->Component = NULL; count = l->ComponentCount - 1; /* only ComponentCount - 1 elements */ if ( ALLOC_ARRAY( l->Component, count, FT_UShort ) ) return error; c = l->Component; if ( ACCESS_Frame( count * 2L ) ) { FREE( c ); return error; } for ( n = 0; n < count; n++ ) c[n] = GET_UShort(); FORGET_Frame(); return TT_Err_Ok; } static void Free_Ligature( TTO_Ligature* l, FT_Memory memory ) { FREE( l->Component ); } /* LigatureSet */ static FT_Error Load_LigatureSet( TTO_LigatureSet* ls, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n = 0, m, count; FT_ULong cur_offset, new_offset, base_offset; TTO_Ligature* l; base_offset = FILE_Pos(); if ( ACCESS_Frame( 2L ) ) return error; count = ls->LigatureCount = GET_UShort(); FORGET_Frame(); ls->Ligature = NULL; if ( ALLOC_ARRAY( ls->Ligature, count, TTO_Ligature ) ) return error; l = ls->Ligature; for ( n = 0; n < count; n++ ) { if ( ACCESS_Frame( 2L ) ) goto Fail; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_Ligature( &l[n], stream ) ) != TT_Err_Ok ) goto Fail; (void)FILE_Seek( cur_offset ); } return TT_Err_Ok; Fail: for ( m = 0; m < n; m++ ) Free_Ligature( &l[m], memory ); FREE( l ); return error; } static void Free_LigatureSet( TTO_LigatureSet* ls, FT_Memory memory ) { FT_UShort n, count; TTO_Ligature* l; if ( ls->Ligature ) { count = ls->LigatureCount; l = ls->Ligature; for ( n = 0; n < count; n++ ) Free_Ligature( &l[n], memory ); FREE( l ); } } /* LigatureSubstFormat1 */ FT_Error Load_LigatureSubst( TTO_LigatureSubst* ls, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n = 0, m, count; FT_ULong cur_offset, new_offset, base_offset; TTO_LigatureSet* lset; base_offset = FILE_Pos(); if ( ACCESS_Frame( 4L ) ) return error; ls->SubstFormat = GET_UShort(); /* should be 1 */ new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_Coverage( &ls->Coverage, stream ) ) != TT_Err_Ok ) return error; (void)FILE_Seek( cur_offset ); if ( ACCESS_Frame( 2L ) ) goto Fail2; count = ls->LigatureSetCount = GET_UShort(); FORGET_Frame(); ls->LigatureSet = NULL; if ( ALLOC_ARRAY( ls->LigatureSet, count, TTO_LigatureSet ) ) goto Fail2; lset = ls->LigatureSet; for ( n = 0; n < count; n++ ) { if ( ACCESS_Frame( 2L ) ) goto Fail1; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_LigatureSet( &lset[n], stream ) ) != TT_Err_Ok ) goto Fail1; (void)FILE_Seek( cur_offset ); } return TT_Err_Ok; Fail1: for ( m = 0; m < n; m++ ) Free_LigatureSet( &lset[m], memory ); FREE( lset ); Fail2: Free_Coverage( &ls->Coverage, memory ); return error; } void Free_LigatureSubst( TTO_LigatureSubst* ls, FT_Memory memory ) { FT_UShort n, count; TTO_LigatureSet* lset; if ( ls->LigatureSet ) { count = ls->LigatureSetCount; lset = ls->LigatureSet; for ( n = 0; n < count; n++ ) Free_LigatureSet( &lset[n], memory ); FREE( lset ); } Free_Coverage( &ls->Coverage, memory ); } static FT_Error Lookup_LigatureSubst( TTO_LigatureSubst* ls, OTL_Buffer buffer, FT_UShort flags, FT_UShort context_length, TTO_GDEFHeader* gdef ) { FT_UShort index, property; FT_Error error; FT_UShort numlig, i, j, is_mark, first_is_mark = FALSE; FT_UShort* c; TTO_Ligature* lig; if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) ) return error; if ( property == TTO_MARK || property & IGNORE_SPECIAL_MARKS ) first_is_mark = TRUE; error = Coverage_Index( &ls->Coverage, IN_CURGLYPH(), &index ); if ( error ) return error; if ( index >= ls->LigatureSetCount ) return TTO_Err_Invalid_GSUB_SubTable; lig = ls->LigatureSet[index].Ligature; for ( numlig = ls->LigatureSet[index].LigatureCount; numlig; numlig--, lig++ ) { if ( buffer->in_pos + lig->ComponentCount > buffer->in_length ) goto next_ligature; /* Not enough glyphs in input */ c = lig->Component; is_mark = first_is_mark; if ( context_length != 0xFFFF && context_length < lig->ComponentCount ) break; for ( i = 1, j = buffer->in_pos + 1; i < lig->ComponentCount; i++, j++ ) { while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) ) { if ( error && error != TTO_Err_Not_Covered ) return error; if ( j + lig->ComponentCount - i == (FT_Int)buffer->in_length ) goto next_ligature; j++; } if ( !( property == TTO_MARK || property & IGNORE_SPECIAL_MARKS ) ) is_mark = FALSE; if ( IN_GLYPH( j ) != c[i - 1] ) goto next_ligature; } if ( gdef && gdef->NewGlyphClasses ) { /* this is just a guess ... */ error = Add_Glyph_Property( gdef, lig->LigGlyph, is_mark ? TTO_MARK : TTO_LIGATURE ); if ( error && error != TTO_Err_Not_Covered ) return error; } if ( j == buffer->in_pos + i ) /* No input glyphs skipped */ { /* We don't use a new ligature ID if there are no skipped glyphs and the ligature already has an ID. */ if ( IN_LIGID( buffer->in_pos ) ) { if ( ADD_String( buffer, i, 1, &lig->LigGlyph, 0xFFFF, 0xFFFF ) ) return error; } else { FT_UShort ligID = otl_buffer_allocate_ligid( buffer ); if ( ADD_String( buffer, i, 1, &lig->LigGlyph, 0xFFFF, ligID ) ) return error; } } else { FT_UShort ligID = otl_buffer_allocate_ligid( buffer ); if ( ADD_Glyph( buffer, lig->LigGlyph, 0xFFFF, ligID ) ) return error; /* Now we must do a second loop to copy the skipped glyphs to `out' and assign component values to it. We start with the glyph after the first component. Glyphs between component i and i+1 belong to component i. Together with the ligID value it is later possible to check whether a specific component value really belongs to a given ligature. */ for ( i = 0; i < lig->ComponentCount - 1; i++ ) { while ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) ) if ( ADD_Glyph( buffer, IN_CURGLYPH(), i, ligID ) ) return error; (buffer->in_pos)++; } } return TT_Err_Ok; next_ligature: ; } return TTO_Err_Not_Covered; } /* Do the actual substitution for a context substitution (either format 5 or 6). This is only called after we've determined that the input matches the subrule. */ static FT_Error Do_ContextSubst( TTO_GSUBHeader* gsub, FT_UShort GlyphCount, FT_UShort SubstCount, TTO_SubstLookupRecord* subst, OTL_Buffer buffer, int nesting_level ) { FT_Error error; FT_UShort i, old_pos; i = 0; while ( i < GlyphCount ) { if ( SubstCount && i == subst->SequenceIndex ) { old_pos = buffer->in_pos; /* Do a substitution */ error = GSub_Do_Glyph_Lookup( gsub, subst->LookupListIndex, buffer, GlyphCount, nesting_level ); subst++; SubstCount--; i += buffer->in_pos - old_pos; if ( error == TTO_Err_Not_Covered ) { /* XXX "can't happen" -- but don't count on it */ if ( ADD_Glyph( buffer, IN_CURGLYPH(), 0xFFFF, 0xFFFF ) ) return error; i++; } else if ( error ) return error; } else { /* No substitution for this index */ if ( ADD_Glyph( buffer, IN_CURGLYPH(), 0xFFFF, 0xFFFF ) ) return error; i++; } } return TT_Err_Ok; } /* LookupType 5 */ /* SubRule */ static FT_Error Load_SubRule( TTO_SubRule* sr, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n, count; FT_UShort* i; TTO_SubstLookupRecord* slr; if ( ACCESS_Frame( 4L ) ) return error; sr->GlyphCount = GET_UShort(); sr->SubstCount = GET_UShort(); FORGET_Frame(); sr->Input = NULL; count = sr->GlyphCount - 1; /* only GlyphCount - 1 elements */ if ( ALLOC_ARRAY( sr->Input, count, FT_UShort ) ) return error; i = sr->Input; if ( ACCESS_Frame( count * 2L ) ) goto Fail2; for ( n = 0; n < count; n++ ) i[n] = GET_UShort(); FORGET_Frame(); sr->SubstLookupRecord = NULL; count = sr->SubstCount; if ( ALLOC_ARRAY( sr->SubstLookupRecord, count, TTO_SubstLookupRecord ) ) goto Fail2; slr = sr->SubstLookupRecord; if ( ACCESS_Frame( count * 4L ) ) goto Fail1; for ( n = 0; n < count; n++ ) { slr[n].SequenceIndex = GET_UShort(); slr[n].LookupListIndex = GET_UShort(); } FORGET_Frame(); return TT_Err_Ok; Fail1: FREE( slr ); Fail2: FREE( i ); return error; } static void Free_SubRule( TTO_SubRule* sr, FT_Memory memory ) { FREE( sr->SubstLookupRecord ); FREE( sr->Input ); } /* SubRuleSet */ static FT_Error Load_SubRuleSet( TTO_SubRuleSet* srs, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n = 0, m, count; FT_ULong cur_offset, new_offset, base_offset; TTO_SubRule* sr; base_offset = FILE_Pos(); if ( ACCESS_Frame( 2L ) ) return error; count = srs->SubRuleCount = GET_UShort(); FORGET_Frame(); srs->SubRule = NULL; if ( ALLOC_ARRAY( srs->SubRule, count, TTO_SubRule ) ) return error; sr = srs->SubRule; for ( n = 0; n < count; n++ ) { if ( ACCESS_Frame( 2L ) ) goto Fail; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_SubRule( &sr[n], stream ) ) != TT_Err_Ok ) goto Fail; (void)FILE_Seek( cur_offset ); } return TT_Err_Ok; Fail: for ( m = 0; m < n; m++ ) Free_SubRule( &sr[m], memory ); FREE( sr ); return error; } static void Free_SubRuleSet( TTO_SubRuleSet* srs, FT_Memory memory ) { FT_UShort n, count; TTO_SubRule* sr; if ( srs->SubRule ) { count = srs->SubRuleCount; sr = srs->SubRule; for ( n = 0; n < count; n++ ) Free_SubRule( &sr[n], memory ); FREE( sr ); } } /* ContextSubstFormat1 */ static FT_Error Load_ContextSubst1( TTO_ContextSubstFormat1* csf1, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n = 0, m, count; FT_ULong cur_offset, new_offset, base_offset; TTO_SubRuleSet* srs; base_offset = FILE_Pos() - 2L; if ( ACCESS_Frame( 2L ) ) return error; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_Coverage( &csf1->Coverage, stream ) ) != TT_Err_Ok ) return error; (void)FILE_Seek( cur_offset ); if ( ACCESS_Frame( 2L ) ) goto Fail2; count = csf1->SubRuleSetCount = GET_UShort(); FORGET_Frame(); csf1->SubRuleSet = NULL; if ( ALLOC_ARRAY( csf1->SubRuleSet, count, TTO_SubRuleSet ) ) goto Fail2; srs = csf1->SubRuleSet; for ( n = 0; n < count; n++ ) { if ( ACCESS_Frame( 2L ) ) goto Fail1; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_SubRuleSet( &srs[n], stream ) ) != TT_Err_Ok ) goto Fail1; (void)FILE_Seek( cur_offset ); } return TT_Err_Ok; Fail1: for ( m = 0; m < n; m++ ) Free_SubRuleSet( &srs[m], memory ); FREE( srs ); Fail2: Free_Coverage( &csf1->Coverage, memory ); return error; } static void Gsub_Free_Context1( TTO_ContextSubstFormat1* csf1, FT_Memory memory ) { FT_UShort n, count; TTO_SubRuleSet* srs; if ( csf1->SubRuleSet ) { count = csf1->SubRuleSetCount; srs = csf1->SubRuleSet; for ( n = 0; n < count; n++ ) Free_SubRuleSet( &srs[n], memory ); FREE( srs ); } Free_Coverage( &csf1->Coverage, memory ); } /* SubClassRule */ static FT_Error Load_SubClassRule( TTO_ContextSubstFormat2* csf2, TTO_SubClassRule* scr, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n, count; FT_UShort* c; TTO_SubstLookupRecord* slr; FT_Bool* d; if ( ACCESS_Frame( 4L ) ) return error; scr->GlyphCount = GET_UShort(); scr->SubstCount = GET_UShort(); if ( scr->GlyphCount > csf2->MaxContextLength ) csf2->MaxContextLength = scr->GlyphCount; FORGET_Frame(); scr->Class = NULL; count = scr->GlyphCount - 1; /* only GlyphCount - 1 elements */ if ( ALLOC_ARRAY( scr->Class, count, FT_UShort ) ) return error; c = scr->Class; d = csf2->ClassDef.Defined; if ( ACCESS_Frame( count * 2L ) ) goto Fail2; for ( n = 0; n < count; n++ ) { c[n] = GET_UShort(); /* We check whether the specific class is used at all. If not, class 0 is used instead. */ if ( !d[c[n]] ) c[n] = 0; } FORGET_Frame(); scr->SubstLookupRecord = NULL; count = scr->SubstCount; if ( ALLOC_ARRAY( scr->SubstLookupRecord, count, TTO_SubstLookupRecord ) ) goto Fail2; slr = scr->SubstLookupRecord; if ( ACCESS_Frame( count * 4L ) ) goto Fail1; for ( n = 0; n < count; n++ ) { slr[n].SequenceIndex = GET_UShort(); slr[n].LookupListIndex = GET_UShort(); } FORGET_Frame(); return TT_Err_Ok; Fail1: FREE( slr ); Fail2: FREE( c ); return error; } static void Free_SubClassRule( TTO_SubClassRule* scr, FT_Memory memory ) { FREE( scr->SubstLookupRecord ); FREE( scr->Class ); } /* SubClassSet */ static FT_Error Load_SubClassSet( TTO_ContextSubstFormat2* csf2, TTO_SubClassSet* scs, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n = 0, m, count; FT_ULong cur_offset, new_offset, base_offset; TTO_SubClassRule* scr; base_offset = FILE_Pos(); if ( ACCESS_Frame( 2L ) ) return error; count = scs->SubClassRuleCount = GET_UShort(); FORGET_Frame(); scs->SubClassRule = NULL; if ( ALLOC_ARRAY( scs->SubClassRule, count, TTO_SubClassRule ) ) return error; scr = scs->SubClassRule; for ( n = 0; n < count; n++ ) { if ( ACCESS_Frame( 2L ) ) goto Fail; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_SubClassRule( csf2, &scr[n], stream ) ) != TT_Err_Ok ) goto Fail; (void)FILE_Seek( cur_offset ); } return TT_Err_Ok; Fail: for ( m = 0; m < n; m++ ) Free_SubClassRule( &scr[m], memory ); FREE( scr ); return error; } static void Free_SubClassSet( TTO_SubClassSet* scs, FT_Memory memory ) { FT_UShort n, count; TTO_SubClassRule* scr; if ( scs->SubClassRule ) { count = scs->SubClassRuleCount; scr = scs->SubClassRule; for ( n = 0; n < count; n++ ) Free_SubClassRule( &scr[n], memory ); FREE( scr ); } } /* ContextSubstFormat2 */ static FT_Error Load_ContextSubst2( TTO_ContextSubstFormat2* csf2, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n = 0, m, count; FT_ULong cur_offset, new_offset, base_offset; TTO_SubClassSet* scs; base_offset = FILE_Pos() - 2; if ( ACCESS_Frame( 2L ) ) return error; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_Coverage( &csf2->Coverage, stream ) ) != TT_Err_Ok ) return error; (void)FILE_Seek( cur_offset ); if ( ACCESS_Frame( 4L ) ) goto Fail3; new_offset = GET_UShort() + base_offset; /* `SubClassSetCount' is the upper limit for class values, thus we read it now to make an additional safety check. */ count = csf2->SubClassSetCount = GET_UShort(); FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_ClassDefinition( &csf2->ClassDef, count, stream ) ) != TT_Err_Ok ) goto Fail3; (void)FILE_Seek( cur_offset ); csf2->SubClassSet = NULL; csf2->MaxContextLength = 0; if ( ALLOC_ARRAY( csf2->SubClassSet, count, TTO_SubClassSet ) ) goto Fail2; scs = csf2->SubClassSet; for ( n = 0; n < count; n++ ) { if ( ACCESS_Frame( 2L ) ) goto Fail1; new_offset = GET_UShort() + base_offset; FORGET_Frame(); if ( new_offset != base_offset ) /* not a NULL offset */ { cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_SubClassSet( csf2, &scs[n], stream ) ) != TT_Err_Ok ) goto Fail1; (void)FILE_Seek( cur_offset ); } else { /* we create a SubClassSet table with no entries */ csf2->SubClassSet[n].SubClassRuleCount = 0; csf2->SubClassSet[n].SubClassRule = NULL; } } return TT_Err_Ok; Fail1: for ( m = 0; m < n; m++ ) Free_SubClassSet( &scs[m], memory ); FREE( scs ); Fail2: Free_ClassDefinition( &csf2->ClassDef, memory ); Fail3: Free_Coverage( &csf2->Coverage, memory ); return error; } static void Gsub_Free_Context2( TTO_ContextSubstFormat2* csf2, FT_Memory memory ) { FT_UShort n, count; TTO_SubClassSet* scs; if ( csf2->SubClassSet ) { count = csf2->SubClassSetCount; scs = csf2->SubClassSet; for ( n = 0; n < count; n++ ) Free_SubClassSet( &scs[n], memory ); FREE( scs ); } Free_ClassDefinition( &csf2->ClassDef, memory ); Free_Coverage( &csf2->Coverage, memory ); } /* ContextSubstFormat3 */ static FT_Error Load_ContextSubst3( TTO_ContextSubstFormat3* csf3, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n = 0, m, count; FT_ULong cur_offset, new_offset, base_offset; TTO_Coverage* c; TTO_SubstLookupRecord* slr; base_offset = FILE_Pos() - 2L; if ( ACCESS_Frame( 4L ) ) return error; csf3->GlyphCount = GET_UShort(); csf3->SubstCount = GET_UShort(); FORGET_Frame(); csf3->Coverage = NULL; count = csf3->GlyphCount; if ( ALLOC_ARRAY( csf3->Coverage, count, TTO_Coverage ) ) return error; c = csf3->Coverage; for ( n = 0; n < count; n++ ) { if ( ACCESS_Frame( 2L ) ) goto Fail2; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_Coverage( &c[n], stream ) ) != TT_Err_Ok ) goto Fail2; (void)FILE_Seek( cur_offset ); } csf3->SubstLookupRecord = NULL; count = csf3->SubstCount; if ( ALLOC_ARRAY( csf3->SubstLookupRecord, count, TTO_SubstLookupRecord ) ) goto Fail2; slr = csf3->SubstLookupRecord; if ( ACCESS_Frame( count * 4L ) ) goto Fail1; for ( n = 0; n < count; n++ ) { slr[n].SequenceIndex = GET_UShort(); slr[n].LookupListIndex = GET_UShort(); } FORGET_Frame(); return TT_Err_Ok; Fail1: FREE( slr ); Fail2: for ( m = 0; m < n; m++ ) Free_Coverage( &c[m], memory ); FREE( c ); return error; } static void Gsub_Free_Context3( TTO_ContextSubstFormat3* csf3, FT_Memory memory ) { FT_UShort n, count; TTO_Coverage* c; FREE( csf3->SubstLookupRecord ); if ( csf3->Coverage ) { count = csf3->GlyphCount; c = csf3->Coverage; for ( n = 0; n < count; n++ ) Free_Coverage( &c[n], memory ); FREE( c ); } } /* ContextSubst */ FT_Error Load_ContextSubst( TTO_ContextSubst* cs, FT_Stream stream ) { FT_Error error; if ( ACCESS_Frame( 2L ) ) return error; cs->SubstFormat = GET_UShort(); FORGET_Frame(); switch ( cs->SubstFormat ) { case 1: return Load_ContextSubst1( &cs->csf.csf1, stream ); case 2: return Load_ContextSubst2( &cs->csf.csf2, stream ); case 3: return Load_ContextSubst3( &cs->csf.csf3, stream ); default: return TTO_Err_Invalid_GSUB_SubTable_Format; } return TT_Err_Ok; /* never reached */ } void Free_ContextSubst( TTO_ContextSubst* cs, FT_Memory memory ) { switch ( cs->SubstFormat ) { case 1: Gsub_Free_Context1( &cs->csf.csf1, memory ); break; case 2: Gsub_Free_Context2( &cs->csf.csf2, memory ); break; case 3: Gsub_Free_Context3( &cs->csf.csf3, memory ); break; } } static FT_Error Lookup_ContextSubst1( TTO_GSUBHeader* gsub, TTO_ContextSubstFormat1* csf1, OTL_Buffer buffer, FT_UShort flags, FT_UShort context_length, int nesting_level ) { FT_UShort index, property; FT_UShort i, j, k, numsr; FT_Error error; TTO_SubRule* sr; TTO_GDEFHeader* gdef; gdef = gsub->gdef; if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) ) return error; error = Coverage_Index( &csf1->Coverage, IN_CURGLYPH(), &index ); if ( error ) return error; sr = csf1->SubRuleSet[index].SubRule; numsr = csf1->SubRuleSet[index].SubRuleCount; for ( k = 0; k < numsr; k++ ) { if ( context_length != 0xFFFF && context_length < sr[k].GlyphCount ) goto next_subrule; if ( buffer->in_pos + sr[k].GlyphCount > buffer->in_length ) goto next_subrule; /* context is too long */ for ( i = 1, j = buffer->in_pos + 1; i < sr[k].GlyphCount; i++, j++ ) { while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) ) { if ( error && error != TTO_Err_Not_Covered ) return error; if ( j + sr[k].GlyphCount - i == (FT_Int)buffer->in_length ) goto next_subrule; j++; } if ( IN_GLYPH( j ) != sr[k].Input[i - 1] ) goto next_subrule; } return Do_ContextSubst( gsub, sr[k].GlyphCount, sr[k].SubstCount, sr[k].SubstLookupRecord, buffer, nesting_level ); next_subrule: ; } return TTO_Err_Not_Covered; } static FT_Error Lookup_ContextSubst2( TTO_GSUBHeader* gsub, TTO_ContextSubstFormat2* csf2, OTL_Buffer buffer, FT_UShort flags, FT_UShort context_length, int nesting_level ) { FT_UShort index, property; FT_Error error; FT_Memory memory = gsub->memory; FT_UShort i, j, k, known_classes; FT_UShort* classes; FT_UShort* cl; TTO_SubClassSet* scs; TTO_SubClassRule* sr; TTO_GDEFHeader* gdef; gdef = gsub->gdef; if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) ) return error; /* Note: The coverage table in format 2 doesn't give an index into anything. It just lets us know whether or not we need to do any lookup at all. */ error = Coverage_Index( &csf2->Coverage, IN_CURGLYPH(), &index ); if ( error ) return error; if ( ALLOC_ARRAY( classes, csf2->MaxContextLength, FT_UShort ) ) return error; error = Get_Class( &csf2->ClassDef, IN_CURGLYPH(), &classes[0], NULL ); if ( error && error != TTO_Err_Not_Covered ) goto End; known_classes = 0; scs = &csf2->SubClassSet[classes[0]]; if ( !scs ) { error = TTO_Err_Invalid_GSUB_SubTable; goto End; } for ( k = 0; k < scs->SubClassRuleCount; k++ ) { sr = &scs->SubClassRule[k]; if ( context_length != 0xFFFF && context_length < sr->GlyphCount ) goto next_subclassrule; if ( buffer->in_pos + sr->GlyphCount > buffer->in_length ) goto next_subclassrule; /* context is too long */ cl = sr->Class; /* Start at 1 because [0] is implied */ for ( i = 1, j = buffer->in_pos + 1; i < sr->GlyphCount; i++, j++ ) { while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) ) { if ( error && error != TTO_Err_Not_Covered ) goto End; if ( j + sr->GlyphCount - i < (FT_Int)buffer->in_length ) goto next_subclassrule; j++; } if ( i > known_classes ) { /* Keeps us from having to do this for each rule */ error = Get_Class( &csf2->ClassDef, IN_GLYPH( j ), &classes[i], NULL ); if ( error && error != TTO_Err_Not_Covered ) goto End; known_classes = i; } if ( cl[i - 1] != classes[i] ) goto next_subclassrule; } error = Do_ContextSubst( gsub, sr->GlyphCount, sr->SubstCount, sr->SubstLookupRecord, buffer, nesting_level ); goto End; next_subclassrule: ; } error = TTO_Err_Not_Covered; End: FREE( classes ); return error; } static FT_Error Lookup_ContextSubst3( TTO_GSUBHeader* gsub, TTO_ContextSubstFormat3* csf3, OTL_Buffer buffer, FT_UShort flags, FT_UShort context_length, int nesting_level ) { FT_Error error; FT_UShort index, i, j, property; TTO_Coverage* c; TTO_GDEFHeader* gdef; gdef = gsub->gdef; if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) ) return error; if ( context_length != 0xFFFF && context_length < csf3->GlyphCount ) return TTO_Err_Not_Covered; if ( buffer->in_pos + csf3->GlyphCount > buffer->in_length ) return TTO_Err_Not_Covered; /* context is too long */ c = csf3->Coverage; for ( i = 1, j = buffer->in_pos + 1; i < csf3->GlyphCount; i++, j++ ) { while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) ) { if ( error && error != TTO_Err_Not_Covered ) return error; if ( j + csf3->GlyphCount - i == (FT_Int)buffer->in_length ) return TTO_Err_Not_Covered; j++; } error = Coverage_Index( &c[i], IN_GLYPH( j ), &index ); if ( error ) return error; } return Do_ContextSubst( gsub, csf3->GlyphCount, csf3->SubstCount, csf3->SubstLookupRecord, buffer, nesting_level ); } static FT_Error Lookup_ContextSubst( TTO_GSUBHeader* gsub, TTO_ContextSubst* cs, OTL_Buffer buffer, FT_UShort flags, FT_UShort context_length, int nesting_level ) { switch ( cs->SubstFormat ) { case 1: return Lookup_ContextSubst1( gsub, &cs->csf.csf1, buffer, flags, context_length, nesting_level ); case 2: return Lookup_ContextSubst2( gsub, &cs->csf.csf2, buffer, flags, context_length, nesting_level ); case 3: return Lookup_ContextSubst3( gsub, &cs->csf.csf3, buffer, flags, context_length, nesting_level ); default: return TTO_Err_Invalid_GSUB_SubTable_Format; } return TT_Err_Ok; /* never reached */ } /* LookupType 6 */ /* ChainSubRule */ static FT_Error Load_ChainSubRule( TTO_ChainSubRule* csr, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n, count; FT_UShort* b; FT_UShort* i; FT_UShort* l; TTO_SubstLookupRecord* slr; if ( ACCESS_Frame( 2L ) ) return error; csr->BacktrackGlyphCount = GET_UShort(); FORGET_Frame(); csr->Backtrack = NULL; count = csr->BacktrackGlyphCount; if ( ALLOC_ARRAY( csr->Backtrack, count, FT_UShort ) ) return error; b = csr->Backtrack; if ( ACCESS_Frame( count * 2L ) ) goto Fail4; for ( n = 0; n < count; n++ ) b[n] = GET_UShort(); FORGET_Frame(); if ( ACCESS_Frame( 2L ) ) goto Fail4; csr->InputGlyphCount = GET_UShort(); FORGET_Frame(); csr->Input = NULL; count = csr->InputGlyphCount - 1; /* only InputGlyphCount - 1 elements */ if ( ALLOC_ARRAY( csr->Input, count, FT_UShort ) ) goto Fail4; i = csr->Input; if ( ACCESS_Frame( count * 2L ) ) goto Fail3; for ( n = 0; n < count; n++ ) i[n] = GET_UShort(); FORGET_Frame(); if ( ACCESS_Frame( 2L ) ) goto Fail3; csr->LookaheadGlyphCount = GET_UShort(); FORGET_Frame(); csr->Lookahead = NULL; count = csr->LookaheadGlyphCount; if ( ALLOC_ARRAY( csr->Lookahead, count, FT_UShort ) ) goto Fail3; l = csr->Lookahead; if ( ACCESS_Frame( count * 2L ) ) goto Fail2; for ( n = 0; n < count; n++ ) l[n] = GET_UShort(); FORGET_Frame(); if ( ACCESS_Frame( 2L ) ) goto Fail2; csr->SubstCount = GET_UShort(); FORGET_Frame(); csr->SubstLookupRecord = NULL; count = csr->SubstCount; if ( ALLOC_ARRAY( csr->SubstLookupRecord, count, TTO_SubstLookupRecord ) ) goto Fail2; slr = csr->SubstLookupRecord; if ( ACCESS_Frame( count * 4L ) ) goto Fail1; for ( n = 0; n < count; n++ ) { slr[n].SequenceIndex = GET_UShort(); slr[n].LookupListIndex = GET_UShort(); } FORGET_Frame(); return TT_Err_Ok; Fail1: FREE( slr ); Fail2: FREE( l ); Fail3: FREE( i ); Fail4: FREE( b ); return error; } static void Gsub_Free_ChainSubRule( TTO_ChainSubRule* csr, FT_Memory memory ) { FREE( csr->SubstLookupRecord ); FREE( csr->Lookahead ); FREE( csr->Input ); FREE( csr->Backtrack ); } /* ChainSubRuleSet */ static FT_Error Load_ChainSubRuleSet( TTO_ChainSubRuleSet* csrs, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n = 0, m, count; FT_ULong cur_offset, new_offset, base_offset; TTO_ChainSubRule* csr; base_offset = FILE_Pos(); if ( ACCESS_Frame( 2L ) ) return error; count = csrs->ChainSubRuleCount = GET_UShort(); FORGET_Frame(); csrs->ChainSubRule = NULL; if ( ALLOC_ARRAY( csrs->ChainSubRule, count, TTO_ChainSubRule ) ) return error; csr = csrs->ChainSubRule; for ( n = 0; n < count; n++ ) { if ( ACCESS_Frame( 2L ) ) goto Fail; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_ChainSubRule( &csr[n], stream ) ) != TT_Err_Ok ) goto Fail; (void)FILE_Seek( cur_offset ); } return TT_Err_Ok; Fail: for ( m = 0; m < n; m++ ) Gsub_Free_ChainSubRule( &csr[m], memory ); FREE( csr ); return error; } static void Gsub_Free_ChainSubRuleSet( TTO_ChainSubRuleSet* csrs, FT_Memory memory ) { FT_UShort n, count; TTO_ChainSubRule* csr; if ( csrs->ChainSubRule ) { count = csrs->ChainSubRuleCount; csr = csrs->ChainSubRule; for ( n = 0; n < count; n++ ) Gsub_Free_ChainSubRule( &csr[n], memory ); FREE( csr ); } } /* ChainContextSubstFormat1 */ static FT_Error Load_ChainContextSubst1( TTO_ChainContextSubstFormat1* ccsf1, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n = 0, m, count; FT_ULong cur_offset, new_offset, base_offset; TTO_ChainSubRuleSet* csrs; base_offset = FILE_Pos() - 2L; if ( ACCESS_Frame( 2L ) ) return error; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_Coverage( &ccsf1->Coverage, stream ) ) != TT_Err_Ok ) return error; (void)FILE_Seek( cur_offset ); if ( ACCESS_Frame( 2L ) ) goto Fail2; count = ccsf1->ChainSubRuleSetCount = GET_UShort(); FORGET_Frame(); ccsf1->ChainSubRuleSet = NULL; if ( ALLOC_ARRAY( ccsf1->ChainSubRuleSet, count, TTO_ChainSubRuleSet ) ) goto Fail2; csrs = ccsf1->ChainSubRuleSet; for ( n = 0; n < count; n++ ) { if ( ACCESS_Frame( 2L ) ) goto Fail1; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_ChainSubRuleSet( &csrs[n], stream ) ) != TT_Err_Ok ) goto Fail1; (void)FILE_Seek( cur_offset ); } return TT_Err_Ok; Fail1: for ( m = 0; m < n; m++ ) Gsub_Free_ChainSubRuleSet( &csrs[m], memory ); FREE( csrs ); Fail2: Free_Coverage( &ccsf1->Coverage, memory ); return error; } static void Gsub_Free_ChainContext1( TTO_ChainContextSubstFormat1* ccsf1, FT_Memory memory ) { FT_UShort n, count; TTO_ChainSubRuleSet* csrs; if ( ccsf1->ChainSubRuleSet ) { count = ccsf1->ChainSubRuleSetCount; csrs = ccsf1->ChainSubRuleSet; for ( n = 0; n < count; n++ ) Gsub_Free_ChainSubRuleSet( &csrs[n], memory ); FREE( csrs ); } Free_Coverage( &ccsf1->Coverage, memory ); } /* ChainSubClassRule */ static FT_Error Load_ChainSubClassRule( TTO_ChainContextSubstFormat2* ccsf2, TTO_ChainSubClassRule* cscr, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n, count; FT_UShort* b; FT_UShort* i; FT_UShort* l; TTO_SubstLookupRecord* slr; FT_Bool* d; if ( ACCESS_Frame( 2L ) ) return error; cscr->BacktrackGlyphCount = GET_UShort(); FORGET_Frame(); if ( cscr->BacktrackGlyphCount > ccsf2->MaxBacktrackLength ) ccsf2->MaxBacktrackLength = cscr->BacktrackGlyphCount; cscr->Backtrack = NULL; count = cscr->BacktrackGlyphCount; if ( ALLOC_ARRAY( cscr->Backtrack, count, FT_UShort ) ) return error; b = cscr->Backtrack; d = ccsf2->BacktrackClassDef.Defined; if ( ACCESS_Frame( count * 2L ) ) goto Fail4; for ( n = 0; n < count; n++ ) { b[n] = GET_UShort(); /* We check whether the specific class is used at all. If not, class 0 is used instead. */ if ( !d[b[n]] ) b[n] = 0; } FORGET_Frame(); if ( ACCESS_Frame( 2L ) ) goto Fail4; cscr->InputGlyphCount = GET_UShort(); FORGET_Frame(); if ( cscr->InputGlyphCount > ccsf2->MaxInputLength ) ccsf2->MaxInputLength = cscr->InputGlyphCount; cscr->Input = NULL; count = cscr->InputGlyphCount - 1; /* only InputGlyphCount - 1 elements */ if ( ALLOC_ARRAY( cscr->Input, count, FT_UShort ) ) goto Fail4; i = cscr->Input; d = ccsf2->InputClassDef.Defined; if ( ACCESS_Frame( count * 2L ) ) goto Fail3; for ( n = 0; n < count; n++ ) { i[n] = GET_UShort(); if ( !d[i[n]] ) i[n] = 0; } FORGET_Frame(); if ( ACCESS_Frame( 2L ) ) goto Fail3; cscr->LookaheadGlyphCount = GET_UShort(); FORGET_Frame(); if ( cscr->LookaheadGlyphCount > ccsf2->MaxLookaheadLength ) ccsf2->MaxLookaheadLength = cscr->LookaheadGlyphCount; cscr->Lookahead = NULL; count = cscr->LookaheadGlyphCount; if ( ALLOC_ARRAY( cscr->Lookahead, count, FT_UShort ) ) goto Fail3; l = cscr->Lookahead; d = ccsf2->LookaheadClassDef.Defined; if ( ACCESS_Frame( count * 2L ) ) goto Fail2; for ( n = 0; n < count; n++ ) { l[n] = GET_UShort(); if ( !d[l[n]] ) l[n] = 0; } FORGET_Frame(); if ( ACCESS_Frame( 2L ) ) goto Fail2; cscr->SubstCount = GET_UShort(); FORGET_Frame(); cscr->SubstLookupRecord = NULL; count = cscr->SubstCount; if ( ALLOC_ARRAY( cscr->SubstLookupRecord, count, TTO_SubstLookupRecord ) ) goto Fail2; slr = cscr->SubstLookupRecord; if ( ACCESS_Frame( count * 4L ) ) goto Fail1; for ( n = 0; n < count; n++ ) { slr[n].SequenceIndex = GET_UShort(); slr[n].LookupListIndex = GET_UShort(); } FORGET_Frame(); return TT_Err_Ok; Fail1: FREE( slr ); Fail2: FREE( l ); Fail3: FREE( i ); Fail4: FREE( b ); return error; } static void Gsub_Free_ChainSubClassRule( TTO_ChainSubClassRule* cscr, FT_Memory memory ) { FREE( cscr->SubstLookupRecord ); FREE( cscr->Lookahead ); FREE( cscr->Input ); FREE( cscr->Backtrack ); } /* SubClassSet */ static FT_Error Load_ChainSubClassSet( TTO_ChainContextSubstFormat2* ccsf2, TTO_ChainSubClassSet* cscs, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n = 0, m, count; FT_ULong cur_offset, new_offset, base_offset; TTO_ChainSubClassRule* cscr; base_offset = FILE_Pos(); if ( ACCESS_Frame( 2L ) ) return error; count = cscs->ChainSubClassRuleCount = GET_UShort(); FORGET_Frame(); cscs->ChainSubClassRule = NULL; if ( ALLOC_ARRAY( cscs->ChainSubClassRule, count, TTO_ChainSubClassRule ) ) return error; cscr = cscs->ChainSubClassRule; for ( n = 0; n < count; n++ ) { if ( ACCESS_Frame( 2L ) ) goto Fail; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_ChainSubClassRule( ccsf2, &cscr[n], stream ) ) != TT_Err_Ok ) goto Fail; (void)FILE_Seek( cur_offset ); } return TT_Err_Ok; Fail: for ( m = 0; m < n; m++ ) Gsub_Free_ChainSubClassRule( &cscr[m], memory ); FREE( cscr ); return error; } static void Gsub_Free_ChainSubClassSet( TTO_ChainSubClassSet* cscs, FT_Memory memory ) { FT_UShort n, count; TTO_ChainSubClassRule* cscr; if ( cscs->ChainSubClassRule ) { count = cscs->ChainSubClassRuleCount; cscr = cscs->ChainSubClassRule; for ( n = 0; n < count; n++ ) Gsub_Free_ChainSubClassRule( &cscr[n], memory ); FREE( cscr ); } } static FT_Error Gsub_Load_EmptyOrClassDefinition( TTO_ClassDefinition* cd, FT_UShort limit, FT_ULong class_offset, FT_ULong base_offset, FT_Stream stream ) { FT_Error error; FT_ULong cur_offset; cur_offset = FILE_Pos(); if ( class_offset ) { if ( !FILE_Seek( class_offset + base_offset ) ) error = Load_ClassDefinition( cd, limit, stream ); } else error = Load_EmptyClassDefinition ( cd, stream ); if (error == TT_Err_Ok) (void)FILE_Seek( cur_offset ); /* Changes error as a side-effect */ return error; } /* ChainContextSubstFormat2 */ static FT_Error Load_ChainContextSubst2( TTO_ChainContextSubstFormat2* ccsf2, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n = 0, m, count; FT_ULong cur_offset, new_offset, base_offset; FT_ULong backtrack_offset, input_offset, lookahead_offset; TTO_ChainSubClassSet* cscs; base_offset = FILE_Pos() - 2; if ( ACCESS_Frame( 2L ) ) return error; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_Coverage( &ccsf2->Coverage, stream ) ) != TT_Err_Ok ) return error; (void)FILE_Seek( cur_offset ); if ( ACCESS_Frame( 8L ) ) goto Fail5; backtrack_offset = GET_UShort(); input_offset = GET_UShort(); lookahead_offset = GET_UShort(); /* `ChainSubClassSetCount' is the upper limit for input class values, thus we read it now to make an additional safety check. No limit is known or needed for the other two class definitions */ count = ccsf2->ChainSubClassSetCount = GET_UShort(); FORGET_Frame(); if ( ( error = Gsub_Load_EmptyOrClassDefinition( &ccsf2->BacktrackClassDef, 65535, backtrack_offset, base_offset, stream ) ) != TT_Err_Ok ) goto Fail5; if ( ( error = Gsub_Load_EmptyOrClassDefinition( &ccsf2->InputClassDef, count, input_offset, base_offset, stream ) ) != TT_Err_Ok ) goto Fail4; if ( ( error = Gsub_Load_EmptyOrClassDefinition( &ccsf2->LookaheadClassDef, 65535, lookahead_offset, base_offset, stream ) ) != TT_Err_Ok ) goto Fail3; ccsf2->ChainSubClassSet = NULL; ccsf2->MaxBacktrackLength = 0; ccsf2->MaxInputLength = 0; ccsf2->MaxLookaheadLength = 0; if ( ALLOC_ARRAY( ccsf2->ChainSubClassSet, count, TTO_ChainSubClassSet ) ) goto Fail2; cscs = ccsf2->ChainSubClassSet; for ( n = 0; n < count; n++ ) { if ( ACCESS_Frame( 2L ) ) goto Fail1; new_offset = GET_UShort() + base_offset; FORGET_Frame(); if ( new_offset != base_offset ) /* not a NULL offset */ { cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_ChainSubClassSet( ccsf2, &cscs[n], stream ) ) != TT_Err_Ok ) goto Fail1; (void)FILE_Seek( cur_offset ); } else { /* we create a ChainSubClassSet table with no entries */ ccsf2->ChainSubClassSet[n].ChainSubClassRuleCount = 0; ccsf2->ChainSubClassSet[n].ChainSubClassRule = NULL; } } return TT_Err_Ok; Fail1: for ( m = 0; m < n; m++ ) Gsub_Free_ChainSubClassSet( &cscs[m], memory ); FREE( cscs ); Fail2: Free_ClassDefinition( &ccsf2->LookaheadClassDef, memory ); Fail3: Free_ClassDefinition( &ccsf2->InputClassDef, memory ); Fail4: Free_ClassDefinition( &ccsf2->BacktrackClassDef, memory ); Fail5: Free_Coverage( &ccsf2->Coverage, memory ); return error; } static void Gsub_Free_ChainContext2( TTO_ChainContextSubstFormat2* ccsf2, FT_Memory memory ) { FT_UShort n, count; TTO_ChainSubClassSet* cscs; if ( ccsf2->ChainSubClassSet ) { count = ccsf2->ChainSubClassSetCount; cscs = ccsf2->ChainSubClassSet; for ( n = 0; n < count; n++ ) Gsub_Free_ChainSubClassSet( &cscs[n], memory ); FREE( cscs ); } Free_ClassDefinition( &ccsf2->LookaheadClassDef, memory ); Free_ClassDefinition( &ccsf2->InputClassDef, memory ); Free_ClassDefinition( &ccsf2->BacktrackClassDef, memory ); Free_Coverage( &ccsf2->Coverage, memory ); } /* ChainContextSubstFormat3 */ static FT_Error Load_ChainContextSubst3( TTO_ChainContextSubstFormat3* ccsf3, FT_Stream stream ) { FT_Error error; FT_Memory memory = stream->memory; FT_UShort n, nb = 0, ni =0, nl = 0, m, count; FT_UShort backtrack_count, input_count, lookahead_count; FT_ULong cur_offset, new_offset, base_offset; TTO_Coverage* b; TTO_Coverage* i; TTO_Coverage* l; TTO_SubstLookupRecord* slr; base_offset = FILE_Pos() - 2L; if ( ACCESS_Frame( 2L ) ) return error; ccsf3->BacktrackGlyphCount = GET_UShort(); FORGET_Frame(); ccsf3->BacktrackCoverage = NULL; backtrack_count = ccsf3->BacktrackGlyphCount; if ( ALLOC_ARRAY( ccsf3->BacktrackCoverage, backtrack_count, TTO_Coverage ) ) return error; b = ccsf3->BacktrackCoverage; for ( nb = 0; nb < backtrack_count; nb++ ) { if ( ACCESS_Frame( 2L ) ) goto Fail4; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_Coverage( &b[nb], stream ) ) != TT_Err_Ok ) goto Fail4; (void)FILE_Seek( cur_offset ); } if ( ACCESS_Frame( 2L ) ) goto Fail4; ccsf3->InputGlyphCount = GET_UShort(); FORGET_Frame(); ccsf3->InputCoverage = NULL; input_count = ccsf3->InputGlyphCount; if ( ALLOC_ARRAY( ccsf3->InputCoverage, input_count, TTO_Coverage ) ) goto Fail4; i = ccsf3->InputCoverage; for ( ni = 0; ni < input_count; ni++ ) { if ( ACCESS_Frame( 2L ) ) goto Fail3; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_Coverage( &i[ni], stream ) ) != TT_Err_Ok ) goto Fail3; (void)FILE_Seek( cur_offset ); } if ( ACCESS_Frame( 2L ) ) goto Fail3; ccsf3->LookaheadGlyphCount = GET_UShort(); FORGET_Frame(); ccsf3->LookaheadCoverage = NULL; lookahead_count = ccsf3->LookaheadGlyphCount; if ( ALLOC_ARRAY( ccsf3->LookaheadCoverage, lookahead_count, TTO_Coverage ) ) goto Fail3; l = ccsf3->LookaheadCoverage; for ( nl = 0; nl < lookahead_count; nl++ ) { if ( ACCESS_Frame( 2L ) ) goto Fail2; new_offset = GET_UShort() + base_offset; FORGET_Frame(); cur_offset = FILE_Pos(); if ( FILE_Seek( new_offset ) || ( error = Load_Coverage( &l[nl], stream ) ) != TT_Err_Ok ) goto Fail2; (void)FILE_Seek( cur_offset ); } if ( ACCESS_Frame( 2L ) ) goto Fail2; ccsf3->SubstCount = GET_UShort(); FORGET_Frame(); ccsf3->SubstLookupRecord = NULL; count = ccsf3->SubstCount; if ( ALLOC_ARRAY( ccsf3->SubstLookupRecord, count, TTO_SubstLookupRecord ) ) goto Fail2; slr = ccsf3->SubstLookupRecord; if ( ACCESS_Frame( count * 4L ) ) goto Fail1; for ( n = 0; n < count; n++ ) { slr[n].SequenceIndex = GET_UShort(); slr[n].LookupListIndex = GET_UShort(); } FORGET_Frame(); return TT_Err_Ok; Fail1: FREE( slr ); Fail2: for ( m = 0; m < nl; m++ ) Free_Coverage( &l[m], memory ); FREE( l ); Fail3: for ( m = 0; m < ni; m++ ) Free_Coverage( &i[m], memory ); FREE( i ); Fail4: for ( m = 0; m < nb; m++ ) Free_Coverage( &b[m], memory ); FREE( b ); return error; } static void Gsub_Free_ChainContext3( TTO_ChainContextSubstFormat3* ccsf3, FT_Memory memory ) { FT_UShort n, count; TTO_Coverage* c; FREE( ccsf3->SubstLookupRecord ); if ( ccsf3->LookaheadCoverage ) { count = ccsf3->LookaheadGlyphCount; c = ccsf3->LookaheadCoverage; for ( n = 0; n < count; n++ ) Free_Coverage( &c[n], memory ); FREE( c ); } if ( ccsf3->InputCoverage ) { count = ccsf3->InputGlyphCount; c = ccsf3->InputCoverage; for ( n = 0; n < count; n++ ) Free_Coverage( &c[n], memory ); FREE( c ); } if ( ccsf3->BacktrackCoverage ) { count = ccsf3->BacktrackGlyphCount; c = ccsf3->BacktrackCoverage; for ( n = 0; n < count; n++ ) Free_Coverage( &c[n], memory ); FREE( c ); } } /* ChainContextSubst */ FT_Error Load_ChainContextSubst( TTO_ChainContextSubst* ccs, FT_Stream stream ) { FT_Error error; if ( ACCESS_Frame( 2L ) ) return error; ccs->SubstFormat = GET_UShort(); FORGET_Frame(); switch ( ccs->SubstFormat ) { case 1: return Load_ChainContextSubst1( &ccs->ccsf.ccsf1, stream ); case 2: return Load_ChainContextSubst2( &ccs->ccsf.ccsf2, stream ); case 3: return Load_ChainContextSubst3( &ccs->ccsf.ccsf3, stream ); default: return TTO_Err_Invalid_GSUB_SubTable_Format; } return TT_Err_Ok; /* never reached */ } void Free_ChainContextSubst( TTO_ChainContextSubst* ccs, FT_Memory memory ) { switch ( ccs->SubstFormat ) { case 1: Gsub_Free_ChainContext1( &ccs->ccsf.ccsf1, memory ); break; case 2: Gsub_Free_ChainContext2( &ccs->ccsf.ccsf2, memory ); break; case 3: Gsub_Free_ChainContext3( &ccs->ccsf.ccsf3, memory ); break; } } static FT_Error Lookup_ChainContextSubst1( TTO_GSUBHeader* gsub, TTO_ChainContextSubstFormat1* ccsf1, OTL_Buffer buffer, FT_UShort flags, FT_UShort context_length, int nesting_level ) { FT_UShort index, property; FT_UShort i, j, k, num_csr; FT_UShort bgc, igc, lgc; FT_Error error; TTO_ChainSubRule* csr; TTO_ChainSubRule curr_csr; TTO_GDEFHeader* gdef; gdef = gsub->gdef; if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) ) return error; error = Coverage_Index( &ccsf1->Coverage, IN_CURGLYPH(), &index ); if ( error ) return error; csr = ccsf1->ChainSubRuleSet[index].ChainSubRule; num_csr = ccsf1->ChainSubRuleSet[index].ChainSubRuleCount; for ( k = 0; k < num_csr; k++ ) { curr_csr = csr[k]; bgc = curr_csr.BacktrackGlyphCount; igc = curr_csr.InputGlyphCount; lgc = curr_csr.LookaheadGlyphCount; if ( context_length != 0xFFFF && context_length < igc ) goto next_chainsubrule; /* check whether context is too long; it is a first guess only */ if ( bgc > buffer->out_pos || buffer->in_pos + igc + lgc > buffer->in_length ) goto next_chainsubrule; if ( bgc ) { /* since we don't know in advance the number of glyphs to inspect, we search backwards for matches in the backtrack glyph array */ for ( i = 0, j = buffer->out_pos - 1; i < bgc; i++, j-- ) { while ( CHECK_Property( gdef, OUT_ITEM( j ), flags, &property ) ) { if ( error && error != TTO_Err_Not_Covered ) return error; if ( j + 1 == bgc - i ) goto next_chainsubrule; j--; } /* In OpenType 1.3, it is undefined whether the offsets of backtrack glyphs is in logical order or not. Version 1.4 will clarify this: Logical order - a b c d e f g h i j i Input offsets - 0 1 Backtrack offsets - 3 2 1 0 Lookahead offsets - 0 1 2 3 */ if ( OUT_GLYPH( j ) != curr_csr.Backtrack[i] ) goto next_chainsubrule; } } /* Start at 1 because [0] is implied */ for ( i = 1, j = buffer->in_pos + 1; i < igc; i++, j++ ) { while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) ) { if ( error && error != TTO_Err_Not_Covered ) return error; if ( j + igc - i + lgc == (FT_Int)buffer->in_length ) goto next_chainsubrule; j++; } if ( IN_GLYPH( j ) != curr_csr.Input[i - 1] ) goto next_chainsubrule; } /* we are starting to check for lookahead glyphs right after the last context glyph */ for ( i = 0; i < lgc; i++, j++ ) { while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) ) { if ( error && error != TTO_Err_Not_Covered ) return error; if ( j + lgc - i == (FT_Int)buffer->in_length ) goto next_chainsubrule; j++; } if ( IN_GLYPH( j ) != curr_csr.Lookahead[i] ) goto next_chainsubrule; } return Do_ContextSubst( gsub, igc, curr_csr.SubstCount, curr_csr.SubstLookupRecord, buffer, nesting_level ); next_chainsubrule: ; } return TTO_Err_Not_Covered; } static FT_Error Lookup_ChainContextSubst2( TTO_GSUBHeader* gsub, TTO_ChainContextSubstFormat2* ccsf2, OTL_Buffer buffer, FT_UShort flags, FT_UShort context_length, int nesting_level ) { FT_UShort index, property; FT_Memory memory; FT_Error error; FT_UShort i, j, k; FT_UShort bgc, igc, lgc; FT_UShort known_backtrack_classes, known_input_classes, known_lookahead_classes; FT_UShort* backtrack_classes; FT_UShort* input_classes; FT_UShort* lookahead_classes; FT_UShort* bc; FT_UShort* ic; FT_UShort* lc; TTO_ChainSubClassSet* cscs; TTO_ChainSubClassRule ccsr; TTO_GDEFHeader* gdef; gdef = gsub->gdef; memory = gsub->memory; if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) ) return error; /* Note: The coverage table in format 2 doesn't give an index into anything. It just lets us know whether or not we need to do any lookup at all. */ error = Coverage_Index( &ccsf2->Coverage, IN_CURGLYPH(), &index ); if ( error ) return error; if ( ALLOC_ARRAY( backtrack_classes, ccsf2->MaxBacktrackLength, FT_UShort ) ) return error; known_backtrack_classes = 0; if ( ALLOC_ARRAY( input_classes, ccsf2->MaxInputLength, FT_UShort ) ) goto End3; known_input_classes = 1; if ( ALLOC_ARRAY( lookahead_classes, ccsf2->MaxLookaheadLength, FT_UShort ) ) goto End2; known_lookahead_classes = 0; error = Get_Class( &ccsf2->InputClassDef, IN_CURGLYPH(), &input_classes[0], NULL ); if ( error && error != TTO_Err_Not_Covered ) goto End1; cscs = &ccsf2->ChainSubClassSet[input_classes[0]]; if ( !cscs ) { error = TTO_Err_Invalid_GSUB_SubTable; goto End1; } for ( k = 0; k < cscs->ChainSubClassRuleCount; k++ ) { ccsr = cscs->ChainSubClassRule[k]; bgc = ccsr.BacktrackGlyphCount; igc = ccsr.InputGlyphCount; lgc = ccsr.LookaheadGlyphCount; if ( context_length != 0xFFFF && context_length < igc ) goto next_chainsubclassrule; /* check whether context is too long; it is a first guess only */ if ( bgc > buffer->out_pos || buffer->in_pos + igc + lgc > buffer->in_length ) goto next_chainsubclassrule; if ( bgc ) { /* Since we don't know in advance the number of glyphs to inspect, we search backwards for matches in the backtrack glyph array. Note that `known_backtrack_classes' starts at index 0. */ bc = ccsr.Backtrack; for ( i = 0, j = buffer->out_pos - 1; i < bgc; i++, j-- ) { while ( CHECK_Property( gdef, OUT_ITEM( j ), flags, &property ) ) { if ( error && error != TTO_Err_Not_Covered ) goto End1; if ( j + 1 == bgc - i ) goto next_chainsubclassrule; j--; } if ( i >= known_backtrack_classes ) { /* Keeps us from having to do this for each rule */ error = Get_Class( &ccsf2->BacktrackClassDef, OUT_GLYPH( j ), &backtrack_classes[i], NULL ); if ( error && error != TTO_Err_Not_Covered ) goto End1; known_backtrack_classes = i; } if ( bc[i] != backtrack_classes[i] ) goto next_chainsubclassrule; } } ic = ccsr.Input; /* Start at 1 because [0] is implied */ for ( i = 1, j = buffer->in_pos + 1; i < igc; i++, j++ ) { while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) ) { if ( error && error != TTO_Err_Not_Covered ) goto End1; if ( j + igc - i + lgc == (FT_Int)buffer->in_length ) goto next_chainsubclassrule; j++; } if ( i >= known_input_classes ) { error = Get_Class( &ccsf2->InputClassDef, IN_GLYPH( j ), &input_classes[i], NULL ); if ( error && error != TTO_Err_Not_Covered ) goto End1; known_input_classes = i; } if ( ic[i - 1] != input_classes[i] ) goto next_chainsubclassrule; } /* we are starting to check for lookahead glyphs right after the last context glyph */ lc = ccsr.Lookahead; for ( i = 0; i < lgc; i++, j++ ) { while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) ) { if ( error && error != TTO_Err_Not_Covered ) goto End1; if ( j + lgc - i == (FT_Int)buffer->in_length ) goto next_chainsubclassrule; j++; } if ( i >= known_lookahead_classes ) { error = Get_Class( &ccsf2->LookaheadClassDef, IN_GLYPH( j ), &lookahead_classes[i], NULL ); if ( error && error != TTO_Err_Not_Covered ) goto End1; known_lookahead_classes = i; } if ( lc[i] != lookahead_classes[i] ) goto next_chainsubclassrule; } error = Do_ContextSubst( gsub, igc, ccsr.SubstCount, ccsr.SubstLookupRecord, buffer, nesting_level ); goto End1; next_chainsubclassrule: ; } error = TTO_Err_Not_Covered; End1: FREE( lookahead_classes ); End2: FREE( input_classes ); End3: FREE( backtrack_classes ); return error; } static FT_Error Lookup_ChainContextSubst3( TTO_GSUBHeader* gsub, TTO_ChainContextSubstFormat3* ccsf3, OTL_Buffer buffer, FT_UShort flags, FT_UShort context_length, int nesting_level ) { FT_UShort index, i, j, property; FT_UShort bgc, igc, lgc; FT_Error error; TTO_Coverage* bc; TTO_Coverage* ic; TTO_Coverage* lc; TTO_GDEFHeader* gdef; gdef = gsub->gdef; if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) ) return error; bgc = ccsf3->BacktrackGlyphCount; igc = ccsf3->InputGlyphCount; lgc = ccsf3->LookaheadGlyphCount; if ( context_length != 0xFFFF && context_length < igc ) return TTO_Err_Not_Covered; /* check whether context is too long; it is a first guess only */ if ( bgc > buffer->out_pos || buffer->in_pos + igc + lgc > buffer->in_length ) return TTO_Err_Not_Covered; if ( bgc ) { /* Since we don't know in advance the number of glyphs to inspect, we search backwards for matches in the backtrack glyph array */ bc = ccsf3->BacktrackCoverage; for ( i = 0, j = buffer->out_pos - 1; i < bgc; i++, j-- ) { while ( CHECK_Property( gdef, OUT_ITEM( j ), flags, &property ) ) { if ( error && error != TTO_Err_Not_Covered ) return error; if ( j + 1 == bgc - i ) return TTO_Err_Not_Covered; j--; } error = Coverage_Index( &bc[i], OUT_GLYPH( j ), &index ); if ( error ) return error; } } ic = ccsf3->InputCoverage; for ( i = 0, j = buffer->in_pos; i < igc; i++, j++ ) { /* We already called CHECK_Property for IN_GLYPH( buffer->in_pos ) */ while ( j > buffer->in_pos && CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) ) { if ( error && error != TTO_Err_Not_Covered ) return error; if ( j + igc - i + lgc == (FT_Int)buffer->in_length ) return TTO_Err_Not_Covered; j++; } error = Coverage_Index( &ic[i], IN_GLYPH( j ), &index ); if ( error ) return error; } /* we are starting for lookahead glyphs right after the last context glyph */ lc = ccsf3->LookaheadCoverage; for ( i = 0; i < lgc; i++, j++ ) { while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) ) { if ( error && error != TTO_Err_Not_Covered ) return error; if ( j + lgc - i == (FT_Int)buffer->in_length ) return TTO_Err_Not_Covered; j++; } error = Coverage_Index( &lc[i], IN_GLYPH( j ), &index ); if ( error ) return error; } return Do_ContextSubst( gsub, igc, ccsf3->SubstCount, ccsf3->SubstLookupRecord, buffer, nesting_level ); } static FT_Error Lookup_ChainContextSubst( TTO_GSUBHeader* gsub, TTO_ChainContextSubst* ccs, OTL_Buffer buffer, FT_UShort flags, FT_UShort context_length, int nesting_level ) { switch ( ccs->SubstFormat ) { case 1: return Lookup_ChainContextSubst1( gsub, &ccs->ccsf.ccsf1, buffer, flags, context_length, nesting_level ); case 2: return Lookup_ChainContextSubst2( gsub, &ccs->ccsf.ccsf2, buffer, flags, context_length, nesting_level ); case 3: return Lookup_ChainContextSubst3( gsub, &ccs->ccsf.ccsf3, buffer, flags, context_length, nesting_level ); default: return TTO_Err_Invalid_GSUB_SubTable_Format; } return TT_Err_Ok; /* never reached */ } /*********** * GSUB API ***********/ EXPORT_FUNC FT_Error TT_GSUB_Select_Script( TTO_GSUBHeader* gsub, FT_ULong script_tag, FT_UShort* script_index ) { FT_UShort n; TTO_ScriptList* sl; TTO_ScriptRecord* sr; if ( !gsub || !script_index ) return TT_Err_Invalid_Argument; sl = &gsub->ScriptList; sr = sl->ScriptRecord; for ( n = 0; n < sl->ScriptCount; n++ ) if ( script_tag == sr[n].ScriptTag ) { *script_index = n; return TT_Err_Ok; } return TTO_Err_Not_Covered; } EXPORT_FUNC FT_Error TT_GSUB_Select_Language( TTO_GSUBHeader* gsub, FT_ULong language_tag, FT_UShort script_index, FT_UShort* language_index, FT_UShort* req_feature_index ) { FT_UShort n; TTO_ScriptList* sl; TTO_ScriptRecord* sr; TTO_Script* s; TTO_LangSysRecord* lsr; if ( !gsub || !language_index || !req_feature_index ) return TT_Err_Invalid_Argument; sl = &gsub->ScriptList; sr = sl->ScriptRecord; if ( script_index >= sl->ScriptCount ) return TT_Err_Invalid_Argument; s = &sr[script_index].Script; lsr = s->LangSysRecord; for ( n = 0; n < s->LangSysCount; n++ ) if ( language_tag == lsr[n].LangSysTag ) { *language_index = n; *req_feature_index = lsr[n].LangSys.ReqFeatureIndex; return TT_Err_Ok; } return TTO_Err_Not_Covered; } /* selecting 0xFFFF for language_index asks for the values of the default language (DefaultLangSys) */ EXPORT_FUNC FT_Error TT_GSUB_Select_Feature( TTO_GSUBHeader* gsub, FT_ULong feature_tag, FT_UShort script_index, FT_UShort language_index, FT_UShort* feature_index ) { FT_UShort n; TTO_ScriptList* sl; TTO_ScriptRecord* sr; TTO_Script* s; TTO_LangSysRecord* lsr; TTO_LangSys* ls; FT_UShort* fi; TTO_FeatureList* fl; TTO_FeatureRecord* fr; if ( !gsub || !feature_index ) return TT_Err_Invalid_Argument; sl = &gsub->ScriptList; sr = sl->ScriptRecord; fl = &gsub->FeatureList; fr = fl->FeatureRecord; if ( script_index >= sl->ScriptCount ) return TT_Err_Invalid_Argument; s = &sr[script_index].Script; lsr = s->LangSysRecord; if ( language_index == 0xFFFF ) ls = &s->DefaultLangSys; else { if ( language_index >= s->LangSysCount ) return TT_Err_Invalid_Argument; ls = &lsr[language_index].LangSys; } fi = ls->FeatureIndex; for ( n = 0; n < ls->FeatureCount; n++ ) { if ( fi[n] >= fl->FeatureCount ) return TTO_Err_Invalid_GSUB_SubTable_Format; if ( feature_tag == fr[fi[n]].FeatureTag ) { *feature_index = fi[n]; return TT_Err_Ok; } } return TTO_Err_Not_Covered; } /* The next three functions return a null-terminated list */ EXPORT_FUNC FT_Error TT_GSUB_Query_Scripts( TTO_GSUBHeader* gsub, FT_ULong** script_tag_list ) { FT_UShort n; FT_Error error; FT_Memory memory; FT_ULong* stl; TTO_ScriptList* sl; TTO_ScriptRecord* sr; if ( !gsub || !script_tag_list ) return TT_Err_Invalid_Argument; memory = gsub->memory; sl = &gsub->ScriptList; sr = sl->ScriptRecord; if ( ALLOC_ARRAY( stl, sl->ScriptCount + 1, FT_ULong ) ) return error; for ( n = 0; n < sl->ScriptCount; n++ ) stl[n] = sr[n].ScriptTag; stl[n] = 0; *script_tag_list = stl; return TT_Err_Ok; } EXPORT_FUNC FT_Error TT_GSUB_Query_Languages( TTO_GSUBHeader* gsub, FT_UShort script_index, FT_ULong** language_tag_list ) { FT_UShort n; FT_Error error; FT_Memory memory; FT_ULong* ltl; TTO_ScriptList* sl; TTO_ScriptRecord* sr; TTO_Script* s; TTO_LangSysRecord* lsr; if ( !gsub || !language_tag_list ) return TT_Err_Invalid_Argument; memory = gsub->memory; sl = &gsub->ScriptList; sr = sl->ScriptRecord; if ( script_index >= sl->ScriptCount ) return TT_Err_Invalid_Argument; s = &sr[script_index].Script; lsr = s->LangSysRecord; if ( ALLOC_ARRAY( ltl, s->LangSysCount + 1, FT_ULong ) ) return error; for ( n = 0; n < s->LangSysCount; n++ ) ltl[n] = lsr[n].LangSysTag; ltl[n] = 0; *language_tag_list = ltl; return TT_Err_Ok; } /* selecting 0xFFFF for language_index asks for the values of the default language (DefaultLangSys) */ EXPORT_FUNC FT_Error TT_GSUB_Query_Features( TTO_GSUBHeader* gsub, FT_UShort script_index, FT_UShort language_index, FT_ULong** feature_tag_list ) { FT_UShort n; FT_Error error; FT_Memory memory; FT_ULong* ftl; TTO_ScriptList* sl; TTO_ScriptRecord* sr; TTO_Script* s; TTO_LangSysRecord* lsr; TTO_LangSys* ls; FT_UShort* fi; TTO_FeatureList* fl; TTO_FeatureRecord* fr; if ( !gsub || !feature_tag_list ) return TT_Err_Invalid_Argument; memory = gsub->memory; sl = &gsub->ScriptList; sr = sl->ScriptRecord; fl = &gsub->FeatureList; fr = fl->FeatureRecord; if ( script_index >= sl->ScriptCount ) return TT_Err_Invalid_Argument; s = &sr[script_index].Script; lsr = s->LangSysRecord; if ( language_index == 0xFFFF ) ls = &s->DefaultLangSys; else { if ( language_index >= s->LangSysCount ) return TT_Err_Invalid_Argument; ls = &lsr[language_index].LangSys; } fi = ls->FeatureIndex; if ( ALLOC_ARRAY( ftl, ls->FeatureCount + 1, FT_ULong ) ) return error; for ( n = 0; n < ls->FeatureCount; n++ ) { if ( fi[n] >= fl->FeatureCount ) { FREE( ftl ); return TTO_Err_Invalid_GSUB_SubTable_Format; } ftl[n] = fr[fi[n]].FeatureTag; } ftl[n] = 0; *feature_tag_list = ftl; return TT_Err_Ok; } /* Do an individual subtable lookup. Returns TT_Err_Ok if substitution has been done, or TTO_Err_Not_Covered if not. */ static FT_Error GSub_Do_Glyph_Lookup( TTO_GSUBHeader* gsub, FT_UShort lookup_index, OTL_Buffer buffer, FT_UShort context_length, int nesting_level ) { FT_Error error = TTO_Err_Not_Covered; FT_UShort i, flags, lookup_count; TTO_Lookup* lo; nesting_level++; if ( nesting_level > TTO_MAX_NESTING_LEVEL ) return TTO_Err_Too_Many_Nested_Contexts; lookup_count = gsub->LookupList.LookupCount; if (lookup_index >= lookup_count) return error; lo = &gsub->LookupList.Lookup[lookup_index]; flags = lo->LookupFlag; for ( i = 0; i < lo->SubTableCount; i++ ) { switch ( lo->LookupType ) { case GSUB_LOOKUP_SINGLE: error = Lookup_SingleSubst( &lo->SubTable[i].st.gsub.single, buffer, flags, context_length, gsub->gdef ); break; case GSUB_LOOKUP_MULTIPLE: error = Lookup_MultipleSubst( &lo->SubTable[i].st.gsub.multiple, buffer, flags, context_length, gsub->gdef ); break; case GSUB_LOOKUP_ALTERNATE: error = Lookup_AlternateSubst( gsub, &lo->SubTable[i].st.gsub.alternate, buffer, flags, context_length, gsub->gdef ); break; case GSUB_LOOKUP_LIGATURE: error = Lookup_LigatureSubst( &lo->SubTable[i].st.gsub.ligature, buffer, flags, context_length, gsub->gdef ); break; case GSUB_LOOKUP_CONTEXT: error = Lookup_ContextSubst( gsub, &lo->SubTable[i].st.gsub.context, buffer, flags, context_length, nesting_level ); break; case GSUB_LOOKUP_CHAIN: error = Lookup_ChainContextSubst( gsub, &lo->SubTable[i].st.gsub.chain, buffer, flags, context_length, nesting_level ); break; } /* Check whether we have a successful substitution or an error other than TTO_Err_Not_Covered */ if ( error != TTO_Err_Not_Covered ) return error; } return TTO_Err_Not_Covered; } /* apply one lookup to the input string object */ static FT_Error GSub_Do_String_Lookup( TTO_GSUBHeader* gsub, FT_UShort lookup_index, OTL_Buffer buffer ) { FT_Error error, retError = TTO_Err_Not_Covered; FT_UInt* properties = gsub->LookupList.Properties; int nesting_level = 0; while ( buffer->in_pos < buffer->in_length ) { if ( ~IN_PROPERTIES( buffer->in_pos ) & properties[lookup_index] ) { /* 0xFFFF indicates that we don't have a context length yet */ error = GSub_Do_Glyph_Lookup( gsub, lookup_index, buffer, 0xFFFF, nesting_level ); if ( error ) { if ( error != TTO_Err_Not_Covered ) return error; } else retError = error; } else error = TTO_Err_Not_Covered; if ( error == TTO_Err_Not_Covered ) if ( otl_buffer_copy_output_glyph ( buffer ) ) return error; } return retError; } EXPORT_FUNC FT_Error TT_GSUB_Add_Feature( TTO_GSUBHeader* gsub, FT_UShort feature_index, FT_UInt property ) { FT_UShort i; TTO_Feature feature; FT_UInt* properties; FT_UShort* index; FT_UShort lookup_count; /* Each feature can only be added once */ if ( !gsub || feature_index >= gsub->FeatureList.FeatureCount || gsub->FeatureList.ApplyCount == gsub->FeatureList.FeatureCount ) return TT_Err_Invalid_Argument; gsub->FeatureList.ApplyOrder[gsub->FeatureList.ApplyCount++] = feature_index; properties = gsub->LookupList.Properties; feature = gsub->FeatureList.FeatureRecord[feature_index].Feature; index = feature.LookupListIndex; lookup_count = gsub->LookupList.LookupCount; for ( i = 0; i < feature.LookupListCount; i++ ) { FT_UShort lookup_index = index[i]; if (lookup_index < lookup_count) properties[lookup_index] |= property; } return TT_Err_Ok; } EXPORT_FUNC FT_Error TT_GSUB_Clear_Features( TTO_GSUBHeader* gsub ) { FT_UShort i; FT_UInt* properties; if ( !gsub ) return TT_Err_Invalid_Argument; gsub->FeatureList.ApplyCount = 0; properties = gsub->LookupList.Properties; for ( i = 0; i < gsub->LookupList.LookupCount; i++ ) properties[i] = 0; return TT_Err_Ok; } EXPORT_FUNC FT_Error TT_GSUB_Register_Alternate_Function( TTO_GSUBHeader* gsub, TTO_AltFunction altfunc, void* data ) { if ( !gsub ) return TT_Err_Invalid_Argument; gsub->altfunc = altfunc; gsub->data = data; return TT_Err_Ok; } EXPORT_FUNC FT_Error TT_GSUB_Apply_String( TTO_GSUBHeader* gsub, OTL_Buffer buffer ) { FT_Error error, retError = TTO_Err_Not_Covered; FT_UShort i, j, feature_index, lookup_count; TTO_Feature feature; if ( !gsub || !buffer || buffer->in_length == 0 || buffer->in_pos >= buffer->in_length ) return TT_Err_Invalid_Argument; lookup_count = gsub->LookupList.LookupCount; for ( i = 0; i < gsub->FeatureList.ApplyCount; i++) { feature_index = gsub->FeatureList.ApplyOrder[i]; feature = gsub->FeatureList.FeatureRecord[feature_index].Feature; for ( j = 0; j < feature.LookupListCount; j++ ) { FT_UShort lookup_index = feature.LookupListIndex[j]; /* Skip nonexistant lookups */ if (lookup_index >= lookup_count) continue; error = GSub_Do_String_Lookup( gsub, lookup_index, buffer ); if ( error ) { if ( error != TTO_Err_Not_Covered ) goto End; } else retError = error; error = otl_buffer_swap( buffer ); if ( error ) goto End; } } error = retError; End: return error; } /* END */