diff options
Diffstat (limited to 'chromium/third_party/skia/third_party/harfbuzz/src/harfbuzz-gsub.c')
| -rw-r--r-- | chromium/third_party/skia/third_party/harfbuzz/src/harfbuzz-gsub.c | 4329 |
1 files changed, 4329 insertions, 0 deletions
diff --git a/chromium/third_party/skia/third_party/harfbuzz/src/harfbuzz-gsub.c b/chromium/third_party/skia/third_party/harfbuzz/src/harfbuzz-gsub.c new file mode 100644 index 00000000000..21fec51924f --- /dev/null +++ b/chromium/third_party/skia/third_party/harfbuzz/src/harfbuzz-gsub.c @@ -0,0 +1,4329 @@ +/* + * Copyright (C) 1998-2004 David Turner and Werner Lemberg + * Copyright (C) 2006 Behdad Esfahbod + * Copyright (C) 2007 Red Hat, Inc. + * + * This is part of HarfBuzz, an OpenType Layout engine library. + * + * Permission is hereby granted, without written agreement and without + * license or royalty fees, to use, copy, modify, and distribute this + * software and its documentation for any purpose, provided that the + * above copyright notice and the following two paragraphs appear in + * all copies of this software. + * + * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR + * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES + * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN + * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH + * DAMAGE. + * + * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, + * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND + * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS + * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO + * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. + * + * Red Hat Author(s): Behdad Esfahbod + */ + +#include "harfbuzz-impl.h" +#include "harfbuzz-gsub-private.h" +#include "harfbuzz-open-private.h" +#include "harfbuzz-gdef-private.h" + +static HB_Error GSUB_Do_Glyph_Lookup( HB_GSUBHeader* gsub, + HB_UShort lookup_index, + HB_Buffer buffer, + HB_UShort context_length, + int nesting_level ); + + + +/********************** + * Auxiliary functions + **********************/ + + + +HB_Error HB_Load_GSUB_Table( HB_Stream stream, + HB_GSUBHeader** retptr, + HB_GDEFHeader* gdef, + HB_Stream gdefStream ) +{ + HB_Error error; + HB_UInt cur_offset, new_offset, base_offset; + + HB_GSUBHeader* gsub; + + if ( !retptr ) + return ERR(HB_Err_Invalid_Argument); + + if ( GOTO_Table( TTAG_GSUB ) ) + return error; + + base_offset = FILE_Pos(); + + if ( ALLOC ( gsub, sizeof( *gsub ) ) ) + return error; + + + /* 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 = _HB_OPEN_Load_ScriptList( &gsub->ScriptList, + stream ) ) != HB_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 = _HB_OPEN_Load_FeatureList( &gsub->FeatureList, + stream ) ) != HB_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 = _HB_OPEN_Load_LookupList( &gsub->LookupList, + stream, HB_Type_GSUB ) ) != HB_Err_Ok ) + goto Fail2; + + gsub->gdef = gdef; /* can be NULL */ + + if ( ( error = _HB_GDEF_LoadMarkAttachClassDef_From_LookupFlags( gdef, gdefStream, + gsub->LookupList.Lookup, + gsub->LookupList.LookupCount ) ) ) + goto Fail1; + + *retptr = gsub; + + return HB_Err_Ok; + +Fail1: + _HB_OPEN_Free_LookupList( &gsub->LookupList, HB_Type_GSUB ); + +Fail2: + _HB_OPEN_Free_FeatureList( &gsub->FeatureList ); + +Fail3: + _HB_OPEN_Free_ScriptList( &gsub->ScriptList ); + +Fail4: + FREE ( gsub ); + + + return error; +} + + +HB_Error HB_Done_GSUB_Table( HB_GSUBHeader* gsub ) +{ + _HB_OPEN_Free_LookupList( &gsub->LookupList, HB_Type_GSUB ); + _HB_OPEN_Free_FeatureList( &gsub->FeatureList ); + _HB_OPEN_Free_ScriptList( &gsub->ScriptList ); + + FREE( gsub ); + + return HB_Err_Ok; +} + +/***************************** + * SubTable related functions + *****************************/ + + +/* LookupType 1 */ + +/* SingleSubstFormat1 */ +/* SingleSubstFormat2 */ + +static HB_Error Load_SingleSubst( HB_GSUB_SubTable* st, + HB_Stream stream ) +{ + HB_Error error; + HB_SingleSubst* ss = &st->single; + + HB_UShort n, count; + HB_UInt cur_offset, new_offset, base_offset; + + HB_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 = _HB_OPEN_Load_Coverage( &ss->Coverage, stream ) ) != HB_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, HB_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 ERR(HB_Err_Invalid_SubTable_Format); + } + + return HB_Err_Ok; + +Fail1: + FREE( s ); + +Fail2: + _HB_OPEN_Free_Coverage( &ss->Coverage ); + return error; +} + + +static void Free_SingleSubst( HB_GSUB_SubTable* st ) +{ + HB_SingleSubst* ss = &st->single; + + switch ( ss->SubstFormat ) + { + case 1: + break; + + case 2: + FREE( ss->ssf.ssf2.Substitute ); + break; + + default: + break; + } + + _HB_OPEN_Free_Coverage( &ss->Coverage ); +} + + +static HB_Error Lookup_SingleSubst( HB_GSUBHeader* gsub, + HB_GSUB_SubTable* st, + HB_Buffer buffer, + HB_UShort flags, + HB_UShort context_length, + int nesting_level ) +{ + HB_UShort index, value, property; + HB_Error error; + HB_SingleSubst* ss = &st->single; + HB_GDEFHeader* gdef = gsub->gdef; + + HB_UNUSED(nesting_level); + + if ( context_length != 0xFFFF && context_length < 1 ) + return HB_Err_Not_Covered; + + if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) ) + return error; + + error = _HB_OPEN_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 ( REPLACE_Glyph( buffer, value, nesting_level ) ) + return error; + break; + + case 2: + if ( index >= ss->ssf.ssf2.GlyphCount ) + return ERR(HB_Err_Invalid_SubTable); + value = ss->ssf.ssf2.Substitute[index]; + if ( REPLACE_Glyph( buffer, value, nesting_level ) ) + return error; + break; + + default: + return ERR(HB_Err_Invalid_SubTable); + } + + if ( gdef && gdef->NewGlyphClasses ) + { + /* we inherit the old glyph class to the substituted glyph */ + + error = _HB_GDEF_Add_Glyph_Property( gdef, value, property ); + if ( error && error != HB_Err_Not_Covered ) + return error; + } + + return HB_Err_Ok; +} + + +/* LookupType 2 */ + +/* Sequence */ + +static HB_Error Load_Sequence( HB_Sequence* s, + HB_Stream stream ) +{ + HB_Error error; + + HB_UShort n, count; + HB_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, HB_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 HB_Err_Ok; +} + + +static void Free_Sequence( HB_Sequence* s ) +{ + FREE( s->Substitute ); +} + + +/* MultipleSubstFormat1 */ + +static HB_Error Load_MultipleSubst( HB_GSUB_SubTable* st, + HB_Stream stream ) +{ + HB_Error error; + HB_MultipleSubst* ms = &st->multiple; + + HB_UShort n = 0, m, count; + HB_UInt cur_offset, new_offset, base_offset; + + HB_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 = _HB_OPEN_Load_Coverage( &ms->Coverage, stream ) ) != HB_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, HB_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 ) ) != HB_Err_Ok ) + goto Fail1; + (void)FILE_Seek( cur_offset ); + } + + return HB_Err_Ok; + +Fail1: + for ( m = 0; m < n; m++ ) + Free_Sequence( &s[m] ); + + FREE( s ); + +Fail2: + _HB_OPEN_Free_Coverage( &ms->Coverage ); + return error; +} + + +static void Free_MultipleSubst( HB_GSUB_SubTable* st ) +{ + HB_UShort n, count; + HB_MultipleSubst* ms = &st->multiple; + + HB_Sequence* s; + + + if ( ms->Sequence ) + { + count = ms->SequenceCount; + s = ms->Sequence; + + for ( n = 0; n < count; n++ ) + Free_Sequence( &s[n] ); + + FREE( s ); + } + + _HB_OPEN_Free_Coverage( &ms->Coverage ); +} + + +static HB_Error Lookup_MultipleSubst( HB_GSUBHeader* gsub, + HB_GSUB_SubTable* st, + HB_Buffer buffer, + HB_UShort flags, + HB_UShort context_length, + int nesting_level ) +{ + HB_Error error; + HB_UShort index, property, n, count; + HB_UShort*s; + HB_MultipleSubst* ms = &st->multiple; + HB_GDEFHeader* gdef = gsub->gdef; + + HB_UNUSED(nesting_level); + + if ( context_length != 0xFFFF && context_length < 1 ) + return HB_Err_Not_Covered; + + if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) ) + return error; + + error = _HB_OPEN_Coverage_Index( &ms->Coverage, IN_CURGLYPH(), &index ); + if ( error ) + return error; + + if ( index >= ms->SequenceCount ) + return ERR(HB_Err_Invalid_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 == HB_GDEF_LIGATURE ) + property = HB_GDEF_BASE_GLYPH; + + for ( n = 0; n < count; n++ ) + { + error = _HB_GDEF_Add_Glyph_Property( gdef, s[n], property ); + if ( error && error != HB_Err_Not_Covered ) + return error; + } + } + + return HB_Err_Ok; +} + + +/* LookupType 3 */ + +/* AlternateSet */ + +static HB_Error Load_AlternateSet( HB_AlternateSet* as, + HB_Stream stream ) +{ + HB_Error error; + + HB_UShort n, count; + HB_UShort* a; + + + if ( ACCESS_Frame( 2L ) ) + return error; + + count = as->GlyphCount = GET_UShort(); + + FORGET_Frame(); + + as->Alternate = NULL; + + if ( ALLOC_ARRAY( as->Alternate, count, HB_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 HB_Err_Ok; +} + + +static void Free_AlternateSet( HB_AlternateSet* as ) +{ + FREE( as->Alternate ); +} + + +/* AlternateSubstFormat1 */ + +static HB_Error Load_AlternateSubst( HB_GSUB_SubTable* st, + HB_Stream stream ) +{ + HB_Error error; + HB_AlternateSubst* as = &st->alternate; + + HB_UShort n = 0, m, count; + HB_UInt cur_offset, new_offset, base_offset; + + HB_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 = _HB_OPEN_Load_Coverage( &as->Coverage, stream ) ) != HB_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, HB_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 ) ) != HB_Err_Ok ) + goto Fail1; + (void)FILE_Seek( cur_offset ); + } + + return HB_Err_Ok; + +Fail1: + for ( m = 0; m < n; m++ ) + Free_AlternateSet( &aset[m] ); + + FREE( aset ); + +Fail2: + _HB_OPEN_Free_Coverage( &as->Coverage ); + return error; +} + + +static void Free_AlternateSubst( HB_GSUB_SubTable* st ) +{ + HB_UShort n, count; + HB_AlternateSubst* as = &st->alternate; + + HB_AlternateSet* aset; + + + if ( as->AlternateSet ) + { + count = as->AlternateSetCount; + aset = as->AlternateSet; + + for ( n = 0; n < count; n++ ) + Free_AlternateSet( &aset[n] ); + + FREE( aset ); + } + + _HB_OPEN_Free_Coverage( &as->Coverage ); +} + + +static HB_Error Lookup_AlternateSubst( HB_GSUBHeader* gsub, + HB_GSUB_SubTable* st, + HB_Buffer buffer, + HB_UShort flags, + HB_UShort context_length, + int nesting_level ) +{ + HB_Error error; + HB_UShort index, value, alt_index, property; + HB_AlternateSubst* as = &st->alternate; + HB_GDEFHeader* gdef = gsub->gdef; + HB_AlternateSet aset; + + HB_UNUSED(nesting_level); + + if ( context_length != 0xFFFF && context_length < 1 ) + return HB_Err_Not_Covered; + + if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) ) + return error; + + error = _HB_OPEN_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; + + value = aset.Alternate[alt_index]; + if ( REPLACE_Glyph( buffer, value, nesting_level ) ) + return error; + + if ( gdef && gdef->NewGlyphClasses ) + { + /* we inherit the old glyph class to the substituted glyph */ + + error = _HB_GDEF_Add_Glyph_Property( gdef, value, property ); + if ( error && error != HB_Err_Not_Covered ) + return error; + } + + return HB_Err_Ok; +} + + +/* LookupType 4 */ + +/* Ligature */ + +static HB_Error Load_Ligature( HB_Ligature* l, + HB_Stream stream ) +{ + HB_Error error; + + HB_UShort n, count; + HB_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, HB_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 HB_Err_Ok; +} + + +static void Free_Ligature( HB_Ligature* l ) +{ + FREE( l->Component ); +} + + +/* LigatureSet */ + +static HB_Error Load_LigatureSet( HB_LigatureSet* ls, + HB_Stream stream ) +{ + HB_Error error; + + HB_UShort n = 0, m, count; + HB_UInt cur_offset, new_offset, base_offset; + + HB_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, HB_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 ) ) != HB_Err_Ok ) + goto Fail; + (void)FILE_Seek( cur_offset ); + } + + return HB_Err_Ok; + +Fail: + for ( m = 0; m < n; m++ ) + Free_Ligature( &l[m] ); + + FREE( l ); + return error; +} + + +static void Free_LigatureSet( HB_LigatureSet* ls ) +{ + HB_UShort n, count; + + HB_Ligature* l; + + + if ( ls->Ligature ) + { + count = ls->LigatureCount; + l = ls->Ligature; + + for ( n = 0; n < count; n++ ) + Free_Ligature( &l[n] ); + + FREE( l ); + } +} + + +/* LigatureSubstFormat1 */ + +static HB_Error Load_LigatureSubst( HB_GSUB_SubTable* st, + HB_Stream stream ) +{ + HB_Error error; + HB_LigatureSubst* ls = &st->ligature; + + HB_UShort n = 0, m, count; + HB_UInt cur_offset, new_offset, base_offset; + + HB_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 = _HB_OPEN_Load_Coverage( &ls->Coverage, stream ) ) != HB_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, HB_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 ) ) != HB_Err_Ok ) + goto Fail1; + (void)FILE_Seek( cur_offset ); + } + + return HB_Err_Ok; + +Fail1: + for ( m = 0; m < n; m++ ) + Free_LigatureSet( &lset[m] ); + + FREE( lset ); + +Fail2: + _HB_OPEN_Free_Coverage( &ls->Coverage ); + return error; +} + + +static void Free_LigatureSubst( HB_GSUB_SubTable* st ) +{ + HB_UShort n, count; + HB_LigatureSubst* ls = &st->ligature; + + HB_LigatureSet* lset; + + + if ( ls->LigatureSet ) + { + count = ls->LigatureSetCount; + lset = ls->LigatureSet; + + for ( n = 0; n < count; n++ ) + Free_LigatureSet( &lset[n] ); + + FREE( lset ); + } + + _HB_OPEN_Free_Coverage( &ls->Coverage ); +} + + +static HB_Error Lookup_LigatureSubst( HB_GSUBHeader* gsub, + HB_GSUB_SubTable* st, + HB_Buffer buffer, + HB_UShort flags, + HB_UShort context_length, + int nesting_level ) +{ + HB_UShort index, property; + HB_Error error; + HB_UShort numlig, i, j, is_mark, first_is_mark = FALSE; + HB_UShort* c; + HB_LigatureSubst* ls = &st->ligature; + HB_GDEFHeader* gdef = gsub->gdef; + + HB_Ligature* lig; + + HB_UNUSED(nesting_level); + + if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) ) + return error; + + if ( property == HB_GDEF_MARK || property & HB_LOOKUP_FLAG_IGNORE_SPECIAL_MARKS ) + first_is_mark = TRUE; + + error = _HB_OPEN_Coverage_Index( &ls->Coverage, IN_CURGLYPH(), &index ); + if ( error ) + return error; + + if ( index >= ls->LigatureSetCount ) + return ERR(HB_Err_Invalid_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 != HB_Err_Not_Covered ) + return error; + + if ( j + lig->ComponentCount - i == (HB_Int)buffer->in_length ) + goto next_ligature; + j++; + } + + if ( !( property == HB_GDEF_MARK || property & HB_LOOKUP_FLAG_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 = _HB_GDEF_Add_Glyph_Property( gdef, lig->LigGlyph, + is_mark ? HB_GDEF_MARK : HB_GDEF_LIGATURE ); + if ( error && error != HB_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 + { + HB_UShort ligID = _hb_buffer_allocate_ligid( buffer ); + if ( ADD_String( buffer, i, 1, &lig->LigGlyph, + 0xFFFF, ligID ) ) + return error; + } + } + else + { + HB_UShort ligID = _hb_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 HB_Err_Ok; + + next_ligature: + ; + } + + return HB_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 HB_Error Do_ContextSubst( HB_GSUBHeader* gsub, + HB_UShort GlyphCount, + HB_UShort SubstCount, + HB_SubstLookupRecord* subst, + HB_Buffer buffer, + int nesting_level ) +{ + HB_Error error; + HB_UInt 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 == HB_Err_Not_Covered ) + { + if ( COPY_Glyph( buffer ) ) + return error; + i++; + } + else if ( error ) + return error; + } + else + { + /* No substitution for this index */ + + if ( COPY_Glyph( buffer ) ) + return error; + i++; + } + } + + return HB_Err_Ok; +} + + +/* LookupType 5 */ + +/* SubRule */ + +static HB_Error Load_SubRule( HB_SubRule* sr, + HB_Stream stream ) +{ + HB_Error error; + + HB_UShort n, count; + HB_UShort* i; + + HB_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, HB_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, HB_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 HB_Err_Ok; + +Fail1: + FREE( slr ); + +Fail2: + FREE( i ); + return error; +} + + +static void Free_SubRule( HB_SubRule* sr ) +{ + FREE( sr->SubstLookupRecord ); + FREE( sr->Input ); +} + + +/* SubRuleSet */ + +static HB_Error Load_SubRuleSet( HB_SubRuleSet* srs, + HB_Stream stream ) +{ + HB_Error error; + + HB_UShort n = 0, m, count; + HB_UInt cur_offset, new_offset, base_offset; + + HB_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, HB_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 ) ) != HB_Err_Ok ) + goto Fail; + (void)FILE_Seek( cur_offset ); + } + + return HB_Err_Ok; + +Fail: + for ( m = 0; m < n; m++ ) + Free_SubRule( &sr[m] ); + + FREE( sr ); + return error; +} + + +static void Free_SubRuleSet( HB_SubRuleSet* srs ) +{ + HB_UShort n, count; + + HB_SubRule* sr; + + + if ( srs->SubRule ) + { + count = srs->SubRuleCount; + sr = srs->SubRule; + + for ( n = 0; n < count; n++ ) + Free_SubRule( &sr[n] ); + + FREE( sr ); + } +} + + +/* ContextSubstFormat1 */ + +static HB_Error Load_ContextSubst1( HB_ContextSubstFormat1* csf1, + HB_Stream stream ) +{ + HB_Error error; + + HB_UShort n = 0, m, count; + HB_UInt cur_offset, new_offset, base_offset; + + HB_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 = _HB_OPEN_Load_Coverage( &csf1->Coverage, stream ) ) != HB_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, HB_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 ) ) != HB_Err_Ok ) + goto Fail1; + (void)FILE_Seek( cur_offset ); + } + + return HB_Err_Ok; + +Fail1: + for ( m = 0; m < n; m++ ) + Free_SubRuleSet( &srs[m] ); + + FREE( srs ); + +Fail2: + _HB_OPEN_Free_Coverage( &csf1->Coverage ); + return error; +} + + +static void Free_ContextSubst1( HB_ContextSubstFormat1* csf1 ) +{ + HB_UShort n, count; + + HB_SubRuleSet* srs; + + + if ( csf1->SubRuleSet ) + { + count = csf1->SubRuleSetCount; + srs = csf1->SubRuleSet; + + for ( n = 0; n < count; n++ ) + Free_SubRuleSet( &srs[n] ); + + FREE( srs ); + } + + _HB_OPEN_Free_Coverage( &csf1->Coverage ); +} + + +/* SubClassRule */ + +static HB_Error Load_SubClassRule( HB_ContextSubstFormat2* csf2, + HB_SubClassRule* scr, + HB_Stream stream ) +{ + HB_Error error; + + HB_UShort n, count; + + HB_UShort* c; + HB_SubstLookupRecord* slr; + + + 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, HB_UShort ) ) + return error; + + c = scr->Class; + + if ( ACCESS_Frame( count * 2L ) ) + goto Fail2; + + for ( n = 0; n < count; n++ ) + c[n] = GET_UShort(); + + FORGET_Frame(); + + scr->SubstLookupRecord = NULL; + + count = scr->SubstCount; + + if ( ALLOC_ARRAY( scr->SubstLookupRecord, count, HB_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 HB_Err_Ok; + +Fail1: + FREE( slr ); + +Fail2: + FREE( c ); + return error; +} + + +static void Free_SubClassRule( HB_SubClassRule* scr ) +{ + FREE( scr->SubstLookupRecord ); + FREE( scr->Class ); +} + + +/* SubClassSet */ + +static HB_Error Load_SubClassSet( HB_ContextSubstFormat2* csf2, + HB_SubClassSet* scs, + HB_Stream stream ) +{ + HB_Error error; + + HB_UShort n = 0, m, count; + HB_UInt cur_offset, new_offset, base_offset; + + HB_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, HB_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 ) ) != HB_Err_Ok ) + goto Fail; + (void)FILE_Seek( cur_offset ); + } + + return HB_Err_Ok; + +Fail: + for ( m = 0; m < n; m++ ) + Free_SubClassRule( &scr[m] ); + + FREE( scr ); + return error; +} + + +static void Free_SubClassSet( HB_SubClassSet* scs ) +{ + HB_UShort n, count; + + HB_SubClassRule* scr; + + + if ( scs->SubClassRule ) + { + count = scs->SubClassRuleCount; + scr = scs->SubClassRule; + + for ( n = 0; n < count; n++ ) + Free_SubClassRule( &scr[n] ); + + FREE( scr ); + } +} + + +/* ContextSubstFormat2 */ + +static HB_Error Load_ContextSubst2( HB_ContextSubstFormat2* csf2, + HB_Stream stream ) +{ + HB_Error error; + + HB_UShort n = 0, m, count; + HB_UInt cur_offset, new_offset, base_offset; + + HB_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 = _HB_OPEN_Load_Coverage( &csf2->Coverage, stream ) ) != HB_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 = _HB_OPEN_Load_ClassDefinition( &csf2->ClassDef, count, + stream ) ) != HB_Err_Ok ) + goto Fail3; + (void)FILE_Seek( cur_offset ); + + csf2->SubClassSet = NULL; + csf2->MaxContextLength = 0; + + if ( ALLOC_ARRAY( csf2->SubClassSet, count, HB_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 ) ) != HB_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 HB_Err_Ok; + +Fail1: + for ( m = 0; m < n; m++ ) + Free_SubClassSet( &scs[m] ); + + FREE( scs ); + +Fail2: + _HB_OPEN_Free_ClassDefinition( &csf2->ClassDef ); + +Fail3: + _HB_OPEN_Free_Coverage( &csf2->Coverage ); + return error; +} + + +static void Free_ContextSubst2( HB_ContextSubstFormat2* csf2 ) +{ + HB_UShort n, count; + + HB_SubClassSet* scs; + + + if ( csf2->SubClassSet ) + { + count = csf2->SubClassSetCount; + scs = csf2->SubClassSet; + + for ( n = 0; n < count; n++ ) + Free_SubClassSet( &scs[n] ); + + FREE( scs ); + } + + _HB_OPEN_Free_ClassDefinition( &csf2->ClassDef ); + _HB_OPEN_Free_Coverage( &csf2->Coverage ); +} + + +/* ContextSubstFormat3 */ + +static HB_Error Load_ContextSubst3( HB_ContextSubstFormat3* csf3, + HB_Stream stream ) +{ + HB_Error error; + + HB_UShort n = 0, m, count; + HB_UInt cur_offset, new_offset, base_offset; + + HB_Coverage* c; + HB_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, HB_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 = _HB_OPEN_Load_Coverage( &c[n], stream ) ) != HB_Err_Ok ) + goto Fail2; + (void)FILE_Seek( cur_offset ); + } + + csf3->SubstLookupRecord = NULL; + + count = csf3->SubstCount; + + if ( ALLOC_ARRAY( csf3->SubstLookupRecord, count, + HB_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 HB_Err_Ok; + +Fail1: + FREE( slr ); + +Fail2: + for ( m = 0; m < n; m++ ) + _HB_OPEN_Free_Coverage( &c[m] ); + + FREE( c ); + return error; +} + + +static void Free_ContextSubst3( HB_ContextSubstFormat3* csf3 ) +{ + HB_UShort n, count; + + HB_Coverage* c; + + + FREE( csf3->SubstLookupRecord ); + + if ( csf3->Coverage ) + { + count = csf3->GlyphCount; + c = csf3->Coverage; + + for ( n = 0; n < count; n++ ) + _HB_OPEN_Free_Coverage( &c[n] ); + + FREE( c ); + } +} + + +/* ContextSubst */ + +static HB_Error Load_ContextSubst( HB_GSUB_SubTable* st, + HB_Stream stream ) +{ + HB_Error error; + HB_ContextSubst* cs = &st->context; + + + 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 ERR(HB_Err_Invalid_SubTable_Format); + } + + return HB_Err_Ok; /* never reached */ +} + + +static void Free_ContextSubst( HB_GSUB_SubTable* st ) +{ + HB_ContextSubst* cs = &st->context; + + switch ( cs->SubstFormat ) + { + case 1: Free_ContextSubst1( &cs->csf.csf1 ); break; + case 2: Free_ContextSubst2( &cs->csf.csf2 ); break; + case 3: Free_ContextSubst3( &cs->csf.csf3 ); break; + default: break; + } +} + + +static HB_Error Lookup_ContextSubst1( HB_GSUBHeader* gsub, + HB_ContextSubstFormat1* csf1, + HB_Buffer buffer, + HB_UShort flags, + HB_UShort context_length, + int nesting_level ) +{ + HB_UShort index, property; + HB_UShort i, j, k, numsr; + HB_Error error; + + HB_SubRule* sr; + HB_GDEFHeader* gdef; + + + gdef = gsub->gdef; + + if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) ) + return error; + + error = _HB_OPEN_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 != HB_Err_Not_Covered ) + return error; + + if ( j + sr[k].GlyphCount - i == (HB_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 HB_Err_Not_Covered; +} + + +static HB_Error Lookup_ContextSubst2( HB_GSUBHeader* gsub, + HB_ContextSubstFormat2* csf2, + HB_Buffer buffer, + HB_UShort flags, + HB_UShort context_length, + int nesting_level ) +{ + HB_UShort index, property; + HB_Error error; + HB_UShort i, j, k, known_classes; + + HB_UShort* classes; + HB_UShort* cl; + + HB_SubClassSet* scs; + HB_SubClassRule* sr; + HB_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 = _HB_OPEN_Coverage_Index( &csf2->Coverage, IN_CURGLYPH(), &index ); + if ( error ) + return error; + + if (csf2->MaxContextLength < 1) + return HB_Err_Not_Covered; + + if ( ALLOC_ARRAY( classes, csf2->MaxContextLength, HB_UShort ) ) + return error; + + error = _HB_OPEN_Get_Class( &csf2->ClassDef, IN_CURGLYPH(), + &classes[0], NULL ); + if ( error && error != HB_Err_Not_Covered ) + goto End; + known_classes = 0; + + scs = &csf2->SubClassSet[classes[0]]; + if ( !scs ) + { + error = ERR(HB_Err_Invalid_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 != HB_Err_Not_Covered ) + goto End; + + if ( j + sr->GlyphCount - i < (HB_Int)buffer->in_length ) + goto next_subclassrule; + j++; + } + + if ( i > known_classes ) + { + /* Keeps us from having to do this for each rule */ + + error = _HB_OPEN_Get_Class( &csf2->ClassDef, IN_GLYPH( j ), &classes[i], NULL ); + if ( error && error != HB_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 = HB_Err_Not_Covered; + +End: + FREE( classes ); + return error; +} + + +static HB_Error Lookup_ContextSubst3( HB_GSUBHeader* gsub, + HB_ContextSubstFormat3* csf3, + HB_Buffer buffer, + HB_UShort flags, + HB_UShort context_length, + int nesting_level ) +{ + HB_Error error; + HB_UShort index, i, j, property; + + HB_Coverage* c; + HB_GDEFHeader* gdef; + + + gdef = gsub->gdef; + + if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) ) + return error; + + if ( context_length != 0xFFFF && context_length < csf3->GlyphCount ) + return HB_Err_Not_Covered; + + if ( buffer->in_pos + csf3->GlyphCount > buffer->in_length ) + return HB_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 != HB_Err_Not_Covered ) + return error; + + if ( j + csf3->GlyphCount - i == (HB_Int)buffer->in_length ) + return HB_Err_Not_Covered; + j++; + } + + error = _HB_OPEN_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 HB_Error Lookup_ContextSubst( HB_GSUBHeader* gsub, + HB_GSUB_SubTable* st, + HB_Buffer buffer, + HB_UShort flags, + HB_UShort context_length, + int nesting_level ) +{ + HB_ContextSubst* cs = &st->context; + + 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 ERR(HB_Err_Invalid_SubTable_Format); + } + + return HB_Err_Ok; /* never reached */ +} + + +/* LookupType 6 */ + +/* ChainSubRule */ + +static HB_Error Load_ChainSubRule( HB_ChainSubRule* csr, + HB_Stream stream ) +{ + HB_Error error; + + HB_UShort n, count; + HB_UShort* b; + HB_UShort* i; + HB_UShort* l; + + HB_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, HB_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, HB_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, HB_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, HB_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 HB_Err_Ok; + +Fail1: + FREE( slr ); + +Fail2: + FREE( l ); + +Fail3: + FREE( i ); + +Fail4: + FREE( b ); + return error; +} + + +static void Free_ChainSubRule( HB_ChainSubRule* csr ) +{ + FREE( csr->SubstLookupRecord ); + FREE( csr->Lookahead ); + FREE( csr->Input ); + FREE( csr->Backtrack ); +} + + +/* ChainSubRuleSet */ + +static HB_Error Load_ChainSubRuleSet( HB_ChainSubRuleSet* csrs, + HB_Stream stream ) +{ + HB_Error error; + + HB_UShort n = 0, m, count; + HB_UInt cur_offset, new_offset, base_offset; + + HB_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, HB_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 ) ) != HB_Err_Ok ) + goto Fail; + (void)FILE_Seek( cur_offset ); + } + + return HB_Err_Ok; + +Fail: + for ( m = 0; m < n; m++ ) + Free_ChainSubRule( &csr[m] ); + + FREE( csr ); + return error; +} + + +static void Free_ChainSubRuleSet( HB_ChainSubRuleSet* csrs ) +{ + HB_UShort n, count; + + HB_ChainSubRule* csr; + + + if ( csrs->ChainSubRule ) + { + count = csrs->ChainSubRuleCount; + csr = csrs->ChainSubRule; + + for ( n = 0; n < count; n++ ) + Free_ChainSubRule( &csr[n] ); + + FREE( csr ); + } +} + + +/* ChainContextSubstFormat1 */ + +static HB_Error Load_ChainContextSubst1( + HB_ChainContextSubstFormat1* ccsf1, + HB_Stream stream ) +{ + HB_Error error; + + HB_UShort n = 0, m, count; + HB_UInt cur_offset, new_offset, base_offset; + + HB_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 = _HB_OPEN_Load_Coverage( &ccsf1->Coverage, stream ) ) != HB_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, HB_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 ) ) != HB_Err_Ok ) + goto Fail1; + (void)FILE_Seek( cur_offset ); + } + + return HB_Err_Ok; + +Fail1: + for ( m = 0; m < n; m++ ) + Free_ChainSubRuleSet( &csrs[m] ); + + FREE( csrs ); + +Fail2: + _HB_OPEN_Free_Coverage( &ccsf1->Coverage ); + return error; +} + + +static void Free_ChainContextSubst1( HB_ChainContextSubstFormat1* ccsf1 ) +{ + HB_UShort n, count; + + HB_ChainSubRuleSet* csrs; + + + if ( ccsf1->ChainSubRuleSet ) + { + count = ccsf1->ChainSubRuleSetCount; + csrs = ccsf1->ChainSubRuleSet; + + for ( n = 0; n < count; n++ ) + Free_ChainSubRuleSet( &csrs[n] ); + + FREE( csrs ); + } + + _HB_OPEN_Free_Coverage( &ccsf1->Coverage ); +} + + +/* ChainSubClassRule */ + +static HB_Error Load_ChainSubClassRule( + HB_ChainContextSubstFormat2* ccsf2, + HB_ChainSubClassRule* cscr, + HB_Stream stream ) +{ + HB_Error error; + + HB_UShort n, count; + + HB_UShort* b; + HB_UShort* i; + HB_UShort* l; + HB_SubstLookupRecord* slr; + + + 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, HB_UShort ) ) + return error; + + b = cscr->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; + + 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, HB_UShort ) ) + goto Fail4; + + i = cscr->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; + + 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, HB_UShort ) ) + goto Fail3; + + l = cscr->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; + + cscr->SubstCount = GET_UShort(); + + FORGET_Frame(); + + cscr->SubstLookupRecord = NULL; + + count = cscr->SubstCount; + + if ( ALLOC_ARRAY( cscr->SubstLookupRecord, count, + HB_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 HB_Err_Ok; + +Fail1: + FREE( slr ); + +Fail2: + FREE( l ); + +Fail3: + FREE( i ); + +Fail4: + FREE( b ); + return error; +} + + +static void Free_ChainSubClassRule( HB_ChainSubClassRule* cscr ) +{ + FREE( cscr->SubstLookupRecord ); + FREE( cscr->Lookahead ); + FREE( cscr->Input ); + FREE( cscr->Backtrack ); +} + + +/* SubClassSet */ + +static HB_Error Load_ChainSubClassSet( + HB_ChainContextSubstFormat2* ccsf2, + HB_ChainSubClassSet* cscs, + HB_Stream stream ) +{ + HB_Error error; + + HB_UShort n = 0, m, count; + HB_UInt cur_offset, new_offset, base_offset; + + HB_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, + HB_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 ) ) != HB_Err_Ok ) + goto Fail; + (void)FILE_Seek( cur_offset ); + } + + return HB_Err_Ok; + +Fail: + for ( m = 0; m < n; m++ ) + Free_ChainSubClassRule( &cscr[m] ); + + FREE( cscr ); + return error; +} + + +static void Free_ChainSubClassSet( HB_ChainSubClassSet* cscs ) +{ + HB_UShort n, count; + + HB_ChainSubClassRule* cscr; + + + if ( cscs->ChainSubClassRule ) + { + count = cscs->ChainSubClassRuleCount; + cscr = cscs->ChainSubClassRule; + + for ( n = 0; n < count; n++ ) + Free_ChainSubClassRule( &cscr[n] ); + + FREE( cscr ); + } +} + + +/* ChainContextSubstFormat2 */ + +static HB_Error Load_ChainContextSubst2( + HB_ChainContextSubstFormat2* ccsf2, + HB_Stream stream ) +{ + HB_Error error; + + HB_UShort n = 0, m, count; + HB_UInt cur_offset, new_offset, base_offset; + HB_UInt backtrack_offset, input_offset, lookahead_offset; + + HB_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 = _HB_OPEN_Load_Coverage( &ccsf2->Coverage, stream ) ) != HB_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 = _HB_OPEN_Load_EmptyOrClassDefinition( &ccsf2->BacktrackClassDef, 65535, + backtrack_offset, base_offset, + stream ) ) != HB_Err_Ok ) + goto Fail5; + + if ( ( error = _HB_OPEN_Load_EmptyOrClassDefinition( &ccsf2->InputClassDef, count, + input_offset, base_offset, + stream ) ) != HB_Err_Ok ) + goto Fail4; + if ( ( error = _HB_OPEN_Load_EmptyOrClassDefinition( &ccsf2->LookaheadClassDef, 65535, + lookahead_offset, base_offset, + stream ) ) != HB_Err_Ok ) + goto Fail3; + + ccsf2->ChainSubClassSet = NULL; + ccsf2->MaxBacktrackLength = 0; + ccsf2->MaxInputLength = 0; + ccsf2->MaxLookaheadLength = 0; + + if ( ALLOC_ARRAY( ccsf2->ChainSubClassSet, count, HB_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 ) ) != HB_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 HB_Err_Ok; + +Fail1: + for ( m = 0; m < n; m++ ) + Free_ChainSubClassSet( &cscs[m] ); + + FREE( cscs ); + +Fail2: + _HB_OPEN_Free_ClassDefinition( &ccsf2->LookaheadClassDef ); + +Fail3: + _HB_OPEN_Free_ClassDefinition( &ccsf2->InputClassDef ); + +Fail4: + _HB_OPEN_Free_ClassDefinition( &ccsf2->BacktrackClassDef ); + +Fail5: + _HB_OPEN_Free_Coverage( &ccsf2->Coverage ); + return error; +} + + +static void Free_ChainContextSubst2( HB_ChainContextSubstFormat2* ccsf2 ) +{ + HB_UShort n, count; + + HB_ChainSubClassSet* cscs; + + + if ( ccsf2->ChainSubClassSet ) + { + count = ccsf2->ChainSubClassSetCount; + cscs = ccsf2->ChainSubClassSet; + + for ( n = 0; n < count; n++ ) + Free_ChainSubClassSet( &cscs[n] ); + + FREE( cscs ); + } + + _HB_OPEN_Free_ClassDefinition( &ccsf2->LookaheadClassDef ); + _HB_OPEN_Free_ClassDefinition( &ccsf2->InputClassDef ); + _HB_OPEN_Free_ClassDefinition( &ccsf2->BacktrackClassDef ); + + _HB_OPEN_Free_Coverage( &ccsf2->Coverage ); +} + + +/* ChainContextSubstFormat3 */ + +static HB_Error Load_ChainContextSubst3( + HB_ChainContextSubstFormat3* ccsf3, + HB_Stream stream ) +{ + HB_Error error; + + HB_UShort n, nb = 0, ni =0, nl = 0, m, count; + HB_UShort backtrack_count, input_count, lookahead_count; + HB_UInt cur_offset, new_offset, base_offset; + + HB_Coverage* b; + HB_Coverage* i; + HB_Coverage* l; + HB_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, + HB_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 = _HB_OPEN_Load_Coverage( &b[nb], stream ) ) != HB_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, HB_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 = _HB_OPEN_Load_Coverage( &i[ni], stream ) ) != HB_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, + HB_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 = _HB_OPEN_Load_Coverage( &l[nl], stream ) ) != HB_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, + HB_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 HB_Err_Ok; + +Fail1: + FREE( slr ); + +Fail2: + for ( m = 0; m < nl; m++ ) + _HB_OPEN_Free_Coverage( &l[m] ); + + FREE( l ); + +Fail3: + for ( m = 0; m < ni; m++ ) + _HB_OPEN_Free_Coverage( &i[m] ); + + FREE( i ); + +Fail4: + for ( m = 0; m < nb; m++ ) + _HB_OPEN_Free_Coverage( &b[m] ); + + FREE( b ); + return error; +} + + +static void Free_ChainContextSubst3( HB_ChainContextSubstFormat3* ccsf3 ) +{ + HB_UShort n, count; + + HB_Coverage* c; + + + FREE( ccsf3->SubstLookupRecord ); + + if ( ccsf3->LookaheadCoverage ) + { + count = ccsf3->LookaheadGlyphCount; + c = ccsf3->LookaheadCoverage; + + for ( n = 0; n < count; n++ ) + _HB_OPEN_Free_Coverage( &c[n] ); + + FREE( c ); + } + + if ( ccsf3->InputCoverage ) + { + count = ccsf3->InputGlyphCount; + c = ccsf3->InputCoverage; + + for ( n = 0; n < count; n++ ) + _HB_OPEN_Free_Coverage( &c[n] ); + + FREE( c ); + } + + if ( ccsf3->BacktrackCoverage ) + { + count = ccsf3->BacktrackGlyphCount; + c = ccsf3->BacktrackCoverage; + + for ( n = 0; n < count; n++ ) + _HB_OPEN_Free_Coverage( &c[n] ); + + FREE( c ); + } +} + + +/* ChainContextSubst */ + +static HB_Error Load_ChainContextSubst( HB_GSUB_SubTable* st, + HB_Stream stream ) +{ + HB_Error error; + HB_ChainContextSubst* ccs = &st->chain; + + 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 ERR(HB_Err_Invalid_SubTable_Format); + } + + return HB_Err_Ok; /* never reached */ +} + + +static void Free_ChainContextSubst( HB_GSUB_SubTable* st ) +{ + HB_ChainContextSubst* ccs = &st->chain; + + switch ( ccs->SubstFormat ) { + case 1: Free_ChainContextSubst1( &ccs->ccsf.ccsf1 ); break; + case 2: Free_ChainContextSubst2( &ccs->ccsf.ccsf2 ); break; + case 3: Free_ChainContextSubst3( &ccs->ccsf.ccsf3 ); break; + default: break; + } +} + + +static HB_Error Lookup_ChainContextSubst1( HB_GSUBHeader* gsub, + HB_ChainContextSubstFormat1* ccsf1, + HB_Buffer buffer, + HB_UShort flags, + HB_UShort context_length, + int nesting_level ) +{ + HB_UShort index, property; + HB_UShort i, j, k, num_csr; + HB_UShort bgc, igc, lgc; + HB_Error error; + + HB_ChainSubRule* csr; + HB_ChainSubRule curr_csr; + HB_GDEFHeader* gdef; + + + gdef = gsub->gdef; + + if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) ) + return error; + + error = _HB_OPEN_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 != HB_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 != HB_Err_Not_Covered ) + return error; + + if ( j + igc - i + lgc == (HB_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 != HB_Err_Not_Covered ) + return error; + + if ( j + lgc - i == (HB_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 HB_Err_Not_Covered; +} + + +static HB_Error Lookup_ChainContextSubst2( HB_GSUBHeader* gsub, + HB_ChainContextSubstFormat2* ccsf2, + HB_Buffer buffer, + HB_UShort flags, + HB_UShort context_length, + int nesting_level ) +{ + HB_UShort index, property; + HB_Error error; + HB_UShort i, j, k; + HB_UShort bgc, igc, lgc; + HB_UShort known_backtrack_classes, + known_input_classes, + known_lookahead_classes; + + HB_UShort* backtrack_classes; + HB_UShort* input_classes; + HB_UShort* lookahead_classes; + + HB_UShort* bc; + HB_UShort* ic; + HB_UShort* lc; + + HB_ChainSubClassSet* cscs; + HB_ChainSubClassRule ccsr; + HB_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 = _HB_OPEN_Coverage_Index( &ccsf2->Coverage, IN_CURGLYPH(), &index ); + if ( error ) + return error; + + if ( ALLOC_ARRAY( backtrack_classes, ccsf2->MaxBacktrackLength, HB_UShort ) ) + return error; + known_backtrack_classes = 0; + + if (ccsf2->MaxInputLength < 1) + return HB_Err_Not_Covered; + + if ( ALLOC_ARRAY( input_classes, ccsf2->MaxInputLength, HB_UShort ) ) + goto End3; + known_input_classes = 1; + + if ( ALLOC_ARRAY( lookahead_classes, ccsf2->MaxLookaheadLength, HB_UShort ) ) + goto End2; + known_lookahead_classes = 0; + + error = _HB_OPEN_Get_Class( &ccsf2->InputClassDef, IN_CURGLYPH(), + &input_classes[0], NULL ); + if ( error && error != HB_Err_Not_Covered ) + goto End1; + + cscs = &ccsf2->ChainSubClassSet[input_classes[0]]; + if ( !cscs ) + { + error = ERR(HB_Err_Invalid_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 != HB_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 = _HB_OPEN_Get_Class( &ccsf2->BacktrackClassDef, OUT_GLYPH( j ), + &backtrack_classes[i], NULL ); + if ( error && error != HB_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 != HB_Err_Not_Covered ) + goto End1; + + if ( j + igc - i + lgc == (HB_Int)buffer->in_length ) + goto next_chainsubclassrule; + j++; + } + + if ( i >= known_input_classes ) + { + error = _HB_OPEN_Get_Class( &ccsf2->InputClassDef, IN_GLYPH( j ), + &input_classes[i], NULL ); + if ( error && error != HB_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 != HB_Err_Not_Covered ) + goto End1; + + if ( j + lgc - i == (HB_Int)buffer->in_length ) + goto next_chainsubclassrule; + j++; + } + + if ( i >= known_lookahead_classes ) + { + error = _HB_OPEN_Get_Class( &ccsf2->LookaheadClassDef, IN_GLYPH( j ), + &lookahead_classes[i], NULL ); + if ( error && error != HB_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 = HB_Err_Not_Covered; + +End1: + FREE( lookahead_classes ); + +End2: + FREE( input_classes ); + +End3: + FREE( backtrack_classes ); + return error; +} + + +static HB_Error Lookup_ChainContextSubst3( HB_GSUBHeader* gsub, + HB_ChainContextSubstFormat3* ccsf3, + HB_Buffer buffer, + HB_UShort flags, + HB_UShort context_length, + int nesting_level ) +{ + HB_UShort index, i, j, property; + HB_UShort bgc, igc, lgc; + HB_Error error; + + HB_Coverage* bc; + HB_Coverage* ic; + HB_Coverage* lc; + HB_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 HB_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 HB_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 != HB_Err_Not_Covered ) + return error; + + if ( j + 1 == bgc - i ) + return HB_Err_Not_Covered; + j--; + } + + error = _HB_OPEN_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 != HB_Err_Not_Covered ) + return error; + + if ( j + igc - i + lgc == (HB_Int)buffer->in_length ) + return HB_Err_Not_Covered; + j++; + } + + error = _HB_OPEN_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 != HB_Err_Not_Covered ) + return error; + + if ( j + lgc - i == (HB_Int)buffer->in_length ) + return HB_Err_Not_Covered; + j++; + } + + error = _HB_OPEN_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 HB_Error Lookup_ChainContextSubst( HB_GSUBHeader* gsub, + HB_GSUB_SubTable* st, + HB_Buffer buffer, + HB_UShort flags, + HB_UShort context_length, + int nesting_level ) +{ + HB_ChainContextSubst* ccs = &st->chain; + + 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 ERR(HB_Err_Invalid_SubTable_Format); + } +} + + +static HB_Error Load_ReverseChainContextSubst( HB_GSUB_SubTable* st, + HB_Stream stream ) +{ + HB_Error error; + HB_ReverseChainContextSubst* rccs = &st->reverse; + + HB_UShort m, count; + + HB_UShort nb = 0, nl = 0, n; + HB_UShort backtrack_count, lookahead_count; + HB_UInt cur_offset, new_offset, base_offset; + + HB_Coverage* b; + HB_Coverage* l; + HB_UShort* sub; + + base_offset = FILE_Pos(); + + if ( ACCESS_Frame( 2L ) ) + return error; + + rccs->SubstFormat = GET_UShort(); + + if ( rccs->SubstFormat != 1 ) + return ERR(HB_Err_Invalid_SubTable_Format); + + FORGET_Frame(); + + if ( ACCESS_Frame( 2L ) ) + return error; + + new_offset = GET_UShort() + base_offset; + + FORGET_Frame(); + + cur_offset = FILE_Pos(); + if ( FILE_Seek( new_offset ) || + ( error = _HB_OPEN_Load_Coverage( &rccs->Coverage, stream ) ) != HB_Err_Ok ) + return error; + (void)FILE_Seek( cur_offset ); + + + if ( ACCESS_Frame( 2L ) ) + goto Fail4; + + rccs->BacktrackGlyphCount = GET_UShort(); + + FORGET_Frame(); + + rccs->BacktrackCoverage = NULL; + + backtrack_count = rccs->BacktrackGlyphCount; + + if ( ALLOC_ARRAY( rccs->BacktrackCoverage, backtrack_count, + HB_Coverage ) ) + goto Fail4; + + b = rccs->BacktrackCoverage; + + for ( nb = 0; nb < backtrack_count; nb++ ) + { + if ( ACCESS_Frame( 2L ) ) + goto Fail3; + + new_offset = GET_UShort() + base_offset; + + FORGET_Frame(); + + cur_offset = FILE_Pos(); + if ( FILE_Seek( new_offset ) || + ( error = _HB_OPEN_Load_Coverage( &b[nb], stream ) ) != HB_Err_Ok ) + goto Fail3; + (void)FILE_Seek( cur_offset ); + } + + + if ( ACCESS_Frame( 2L ) ) + goto Fail3; + + rccs->LookaheadGlyphCount = GET_UShort(); + + FORGET_Frame(); + + rccs->LookaheadCoverage = NULL; + + lookahead_count = rccs->LookaheadGlyphCount; + + if ( ALLOC_ARRAY( rccs->LookaheadCoverage, lookahead_count, + HB_Coverage ) ) + goto Fail3; + + l = rccs->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 = _HB_OPEN_Load_Coverage( &l[nl], stream ) ) != HB_Err_Ok ) + goto Fail2; + (void)FILE_Seek( cur_offset ); + } + + if ( ACCESS_Frame( 2L ) ) + goto Fail2; + + rccs->GlyphCount = GET_UShort(); + + FORGET_Frame(); + + rccs->Substitute = NULL; + + count = rccs->GlyphCount; + + if ( ALLOC_ARRAY( rccs->Substitute, count, + HB_UShort ) ) + goto Fail2; + + sub = rccs->Substitute; + + if ( ACCESS_Frame( count * 2L ) ) + goto Fail1; + + for ( n = 0; n < count; n++ ) + sub[n] = GET_UShort(); + + FORGET_Frame(); + + return HB_Err_Ok; + +Fail1: + FREE( sub ); + +Fail2: + for ( m = 0; m < nl; m++ ) + _HB_OPEN_Free_Coverage( &l[m] ); + + FREE( l ); + +Fail3: + for ( m = 0; m < nb; m++ ) + _HB_OPEN_Free_Coverage( &b[m] ); + + FREE( b ); + +Fail4: + _HB_OPEN_Free_Coverage( &rccs->Coverage ); + return error; +} + + +static void Free_ReverseChainContextSubst( HB_GSUB_SubTable* st ) +{ + HB_UShort n, count; + HB_ReverseChainContextSubst* rccs = &st->reverse; + + HB_Coverage* c; + + _HB_OPEN_Free_Coverage( &rccs->Coverage ); + + if ( rccs->LookaheadCoverage ) + { + count = rccs->LookaheadGlyphCount; + c = rccs->LookaheadCoverage; + + for ( n = 0; n < count; n++ ) + _HB_OPEN_Free_Coverage( &c[n] ); + + FREE( c ); + } + + if ( rccs->BacktrackCoverage ) + { + count = rccs->BacktrackGlyphCount; + c = rccs->BacktrackCoverage; + + for ( n = 0; n < count; n++ ) + _HB_OPEN_Free_Coverage( &c[n] ); + + FREE( c ); + } + + FREE ( rccs->Substitute ); +} + + +static HB_Error Lookup_ReverseChainContextSubst( HB_GSUBHeader* gsub, + HB_GSUB_SubTable* st, + HB_Buffer buffer, + HB_UShort flags, + HB_UShort context_length, + int nesting_level ) +{ + HB_UShort index, input_index, i, j, property; + HB_UShort bgc, lgc; + HB_Error error; + + HB_ReverseChainContextSubst* rccs = &st->reverse; + HB_Coverage* bc; + HB_Coverage* lc; + HB_GDEFHeader* gdef; + + if ( nesting_level != 1 || context_length != 0xFFFF ) + return HB_Err_Not_Covered; + + gdef = gsub->gdef; + + if ( CHECK_Property( gdef, IN_CURITEM(), flags, &property ) ) + return error; + + bgc = rccs->BacktrackGlyphCount; + lgc = rccs->LookaheadGlyphCount; + + /* check whether context is too long; it is a first guess only */ + + if ( bgc > buffer->in_pos || buffer->in_pos + 1 + lgc > buffer->in_length ) + return HB_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 = rccs->BacktrackCoverage; + + for ( i = 0, j = buffer->in_pos - 1; i < bgc; i++, j-- ) + { + while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) ) + { + if ( error && error != HB_Err_Not_Covered ) + return error; + + if ( j + 1 == bgc - i ) + return HB_Err_Not_Covered; + j--; + } + + error = _HB_OPEN_Coverage_Index( &bc[i], IN_GLYPH( j ), &index ); + if ( error ) + return error; + } + } + + j = buffer->in_pos; + + error = _HB_OPEN_Coverage_Index( &rccs->Coverage, IN_GLYPH( j ), &input_index ); + if ( error ) + return error; + + lc = rccs->LookaheadCoverage; + + for ( i = 0, j = buffer->in_pos + 1; i < lgc; i++, j++ ) + { + while ( CHECK_Property( gdef, IN_ITEM( j ), flags, &property ) ) + { + if ( error && error != HB_Err_Not_Covered ) + return error; + + if ( j + lgc - i == (HB_Int)buffer->in_length ) + return HB_Err_Not_Covered; + j++; + } + + error = _HB_OPEN_Coverage_Index( &lc[i], IN_GLYPH( j ), &index ); + if ( error ) + return error; + } + + IN_CURGLYPH() = rccs->Substitute[input_index]; + buffer->in_pos--; /* Reverse! */ + + return error; +} + + + +/*********** + * GSUB API + ***********/ + + + +HB_Error HB_GSUB_Select_Script( HB_GSUBHeader* gsub, + HB_UInt script_tag, + HB_UShort* script_index ) +{ + HB_UShort n; + + HB_ScriptList* sl; + HB_ScriptRecord* sr; + + + if ( !gsub || !script_index ) + return ERR(HB_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 HB_Err_Ok; + } + + return HB_Err_Not_Covered; +} + + + +HB_Error HB_GSUB_Select_Language( HB_GSUBHeader* gsub, + HB_UInt language_tag, + HB_UShort script_index, + HB_UShort* language_index, + HB_UShort* req_feature_index ) +{ + HB_UShort n; + + HB_ScriptList* sl; + HB_ScriptRecord* sr; + HB_ScriptTable* s; + HB_LangSysRecord* lsr; + + + if ( !gsub || !language_index || !req_feature_index ) + return ERR(HB_Err_Invalid_Argument); + + sl = &gsub->ScriptList; + sr = sl->ScriptRecord; + + if ( script_index >= sl->ScriptCount ) + return ERR(HB_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 HB_Err_Ok; + } + + return HB_Err_Not_Covered; +} + + +/* selecting 0xFFFF for language_index asks for the values of the + default language (DefaultLangSys) */ + + +HB_Error HB_GSUB_Select_Feature( HB_GSUBHeader* gsub, + HB_UInt feature_tag, + HB_UShort script_index, + HB_UShort language_index, + HB_UShort* feature_index ) +{ + HB_UShort n; + + HB_ScriptList* sl; + HB_ScriptRecord* sr; + HB_ScriptTable* s; + HB_LangSysRecord* lsr; + HB_LangSys* ls; + HB_UShort* fi; + + HB_FeatureList* fl; + HB_FeatureRecord* fr; + + + if ( !gsub || !feature_index ) + return ERR(HB_Err_Invalid_Argument); + + sl = &gsub->ScriptList; + sr = sl->ScriptRecord; + + fl = &gsub->FeatureList; + fr = fl->FeatureRecord; + + if ( script_index >= sl->ScriptCount ) + return ERR(HB_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 ERR(HB_Err_Invalid_Argument); + + ls = &lsr[language_index].LangSys; + } + + fi = ls->FeatureIndex; + + for ( n = 0; n < ls->FeatureCount; n++ ) + { + if ( fi[n] >= fl->FeatureCount ) + return ERR(HB_Err_Invalid_SubTable_Format); + + if ( feature_tag == fr[fi[n]].FeatureTag ) + { + *feature_index = fi[n]; + + return HB_Err_Ok; + } + } + + return HB_Err_Not_Covered; +} + + +/* The next three functions return a null-terminated list */ + + +HB_Error HB_GSUB_Query_Scripts( HB_GSUBHeader* gsub, + HB_UInt** script_tag_list ) +{ + HB_UShort n; + HB_Error error; + HB_UInt* stl; + + HB_ScriptList* sl; + HB_ScriptRecord* sr; + + + if ( !gsub || !script_tag_list ) + return ERR(HB_Err_Invalid_Argument); + + sl = &gsub->ScriptList; + sr = sl->ScriptRecord; + + if ( ALLOC_ARRAY( stl, sl->ScriptCount + 1, HB_UInt ) ) + return error; + + for ( n = 0; n < sl->ScriptCount; n++ ) + stl[n] = sr[n].ScriptTag; + stl[n] = 0; + + *script_tag_list = stl; + + return HB_Err_Ok; +} + + + +HB_Error HB_GSUB_Query_Languages( HB_GSUBHeader* gsub, + HB_UShort script_index, + HB_UInt** language_tag_list ) +{ + HB_UShort n; + HB_Error error; + HB_UInt* ltl; + + HB_ScriptList* sl; + HB_ScriptRecord* sr; + HB_ScriptTable* s; + HB_LangSysRecord* lsr; + + + if ( !gsub || !language_tag_list ) + return ERR(HB_Err_Invalid_Argument); + + sl = &gsub->ScriptList; + sr = sl->ScriptRecord; + + if ( script_index >= sl->ScriptCount ) + return ERR(HB_Err_Invalid_Argument); + + s = &sr[script_index].Script; + lsr = s->LangSysRecord; + + if ( ALLOC_ARRAY( ltl, s->LangSysCount + 1, HB_UInt ) ) + return error; + + for ( n = 0; n < s->LangSysCount; n++ ) + ltl[n] = lsr[n].LangSysTag; + ltl[n] = 0; + + *language_tag_list = ltl; + + return HB_Err_Ok; +} + + +/* selecting 0xFFFF for language_index asks for the values of the + default language (DefaultLangSys) */ + + +HB_Error HB_GSUB_Query_Features( HB_GSUBHeader* gsub, + HB_UShort script_index, + HB_UShort language_index, + HB_UInt** feature_tag_list ) +{ + HB_UShort n; + HB_Error error; + HB_UInt* ftl; + + HB_ScriptList* sl; + HB_ScriptRecord* sr; + HB_ScriptTable* s; + HB_LangSysRecord* lsr; + HB_LangSys* ls; + HB_UShort* fi; + + HB_FeatureList* fl; + HB_FeatureRecord* fr; + + + if ( !gsub || !feature_tag_list ) + return ERR(HB_Err_Invalid_Argument); + + sl = &gsub->ScriptList; + sr = sl->ScriptRecord; + + fl = &gsub->FeatureList; + fr = fl->FeatureRecord; + + if ( script_index >= sl->ScriptCount ) + return ERR(HB_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 ERR(HB_Err_Invalid_Argument); + + ls = &lsr[language_index].LangSys; + } + + fi = ls->FeatureIndex; + + if ( ALLOC_ARRAY( ftl, ls->FeatureCount + 1, HB_UInt ) ) + return error; + + for ( n = 0; n < ls->FeatureCount; n++ ) + { + if ( fi[n] >= fl->FeatureCount ) + { + FREE( ftl ); + return ERR(HB_Err_Invalid_SubTable_Format); + } + ftl[n] = fr[fi[n]].FeatureTag; + } + ftl[n] = 0; + + *feature_tag_list = ftl; + + return HB_Err_Ok; +} + + +/* Do an individual subtable lookup. Returns HB_Err_Ok if substitution + has been done, or HB_Err_Not_Covered if not. */ +static HB_Error GSUB_Do_Glyph_Lookup( HB_GSUBHeader* gsub, + HB_UShort lookup_index, + HB_Buffer buffer, + HB_UShort context_length, + int nesting_level ) +{ + HB_Error error = HB_Err_Not_Covered; + HB_UShort i, flags, lookup_count; + HB_Lookup* lo; + int lookup_type; + + nesting_level++; + + if ( nesting_level > HB_MAX_NESTING_LEVEL ) + return ERR(HB_Err_Not_Covered); /* ERR() call intended */ + + lookup_count = gsub->LookupList.LookupCount; + if (lookup_index >= lookup_count) + return error; + + lo = &gsub->LookupList.Lookup[lookup_index]; + flags = lo->LookupFlag; + lookup_type = lo->LookupType; + + for ( i = 0; i < lo->SubTableCount; i++ ) + { + HB_GSUB_SubTable *st = &lo->SubTable[i].st.gsub; + + switch (lookup_type) { + case HB_GSUB_LOOKUP_SINGLE: + error = Lookup_SingleSubst ( gsub, st, buffer, flags, context_length, nesting_level ); break; + case HB_GSUB_LOOKUP_MULTIPLE: + error = Lookup_MultipleSubst ( gsub, st, buffer, flags, context_length, nesting_level ); break; + case HB_GSUB_LOOKUP_ALTERNATE: + error = Lookup_AlternateSubst ( gsub, st, buffer, flags, context_length, nesting_level ); break; + case HB_GSUB_LOOKUP_LIGATURE: + error = Lookup_LigatureSubst ( gsub, st, buffer, flags, context_length, nesting_level ); break; + case HB_GSUB_LOOKUP_CONTEXT: + error = Lookup_ContextSubst ( gsub, st, buffer, flags, context_length, nesting_level ); break; + case HB_GSUB_LOOKUP_CHAIN: + error = Lookup_ChainContextSubst ( gsub, st, buffer, flags, context_length, nesting_level ); break; + /*case HB_GSUB_LOOKUP_EXTENSION: + error = Lookup_ExtensionSubst ( gsub, st, buffer, flags, context_length, nesting_level ); break;*/ + case HB_GSUB_LOOKUP_REVERSE_CHAIN: + error = Lookup_ReverseChainContextSubst ( gsub, st, buffer, flags, context_length, nesting_level ); break; + default: + error = HB_Err_Not_Covered; + }; + + /* Check whether we have a successful substitution or an error other + than HB_Err_Not_Covered */ + if ( error != HB_Err_Not_Covered ) + return error; + } + + return HB_Err_Not_Covered; +} + + +HB_INTERNAL HB_Error +_HB_GSUB_Load_SubTable( HB_GSUB_SubTable* st, + HB_Stream stream, + HB_UShort lookup_type ) +{ + switch (lookup_type) { + case HB_GSUB_LOOKUP_SINGLE: return Load_SingleSubst ( st, stream ); + case HB_GSUB_LOOKUP_MULTIPLE: return Load_MultipleSubst ( st, stream ); + case HB_GSUB_LOOKUP_ALTERNATE: return Load_AlternateSubst ( st, stream ); + case HB_GSUB_LOOKUP_LIGATURE: return Load_LigatureSubst ( st, stream ); + case HB_GSUB_LOOKUP_CONTEXT: return Load_ContextSubst ( st, stream ); + case HB_GSUB_LOOKUP_CHAIN: return Load_ChainContextSubst ( st, stream ); + /*case HB_GSUB_LOOKUP_EXTENSION: return Load_ExtensionSubst ( st, stream );*/ + case HB_GSUB_LOOKUP_REVERSE_CHAIN: return Load_ReverseChainContextSubst ( st, stream ); + default: return ERR(HB_Err_Invalid_SubTable_Format); + }; +} + + +HB_INTERNAL void +_HB_GSUB_Free_SubTable( HB_GSUB_SubTable* st, + HB_UShort lookup_type ) +{ + switch ( lookup_type ) { + case HB_GSUB_LOOKUP_SINGLE: Free_SingleSubst ( st ); return; + case HB_GSUB_LOOKUP_MULTIPLE: Free_MultipleSubst ( st ); return; + case HB_GSUB_LOOKUP_ALTERNATE: Free_AlternateSubst ( st ); return; + case HB_GSUB_LOOKUP_LIGATURE: Free_LigatureSubst ( st ); return; + case HB_GSUB_LOOKUP_CONTEXT: Free_ContextSubst ( st ); return; + case HB_GSUB_LOOKUP_CHAIN: Free_ChainContextSubst ( st ); return; + /*case HB_GSUB_LOOKUP_EXTENSION: Free_ExtensionSubst ( st ); return;*/ + case HB_GSUB_LOOKUP_REVERSE_CHAIN: Free_ReverseChainContextSubst ( st ); return; + default: return; + }; +} + + + +/* apply one lookup to the input string object */ + +static HB_Error GSUB_Do_String_Lookup( HB_GSUBHeader* gsub, + HB_UShort lookup_index, + HB_Buffer buffer ) +{ + HB_Error error, retError = HB_Err_Not_Covered; + + HB_UInt* properties = gsub->LookupList.Properties; + int lookup_type = gsub->LookupList.Lookup[lookup_index].LookupType; + + const int nesting_level = 0; + /* 0xFFFF indicates that we don't have a context length yet */ + const HB_UShort context_length = 0xFFFF; + + switch (lookup_type) { + + case HB_GSUB_LOOKUP_SINGLE: + case HB_GSUB_LOOKUP_MULTIPLE: + case HB_GSUB_LOOKUP_ALTERNATE: + case HB_GSUB_LOOKUP_LIGATURE: + case HB_GSUB_LOOKUP_CONTEXT: + case HB_GSUB_LOOKUP_CHAIN: + /* in/out forward substitution (implemented lazy) */ + + _hb_buffer_clear_output ( buffer ); + buffer->in_pos = 0; + while ( buffer->in_pos < buffer->in_length ) + { + if ( ~IN_PROPERTIES( buffer->in_pos ) & properties[lookup_index] ) + { + error = GSUB_Do_Glyph_Lookup( gsub, lookup_index, buffer, context_length, nesting_level ); + if ( error ) + { + if ( error != HB_Err_Not_Covered ) + return error; + } + else + retError = error; + } + else + error = HB_Err_Not_Covered; + + if ( error == HB_Err_Not_Covered ) + if ( COPY_Glyph ( buffer ) ) + return error; + } + /* we shouldn't swap if error occurred. + * + * also don't swap if nothing changed (ie HB_Err_Not_Covered). + * shouldn't matter in that case though. + */ + if ( retError == HB_Err_Ok ) + _hb_buffer_swap( buffer ); + + return retError; + + case HB_GSUB_LOOKUP_REVERSE_CHAIN: + /* in-place backward substitution */ + + buffer->in_pos = buffer->in_length - 1; + do + { + if ( ~IN_PROPERTIES( buffer->in_pos ) & properties[lookup_index] ) + { + error = GSUB_Do_Glyph_Lookup( gsub, lookup_index, buffer, context_length, nesting_level ); + if ( error ) + { + if ( error != HB_Err_Not_Covered ) + return error; + } + else + retError = error; + } + else + error = HB_Err_Not_Covered; + + if ( error == HB_Err_Not_Covered ) + buffer->in_pos--; + } + while ((HB_Int) buffer->in_pos >= 0); + + return retError; + + /*case HB_GSUB_LOOKUP_EXTENSION:*/ + default: + return retError; + }; +} + + +HB_Error HB_GSUB_Add_Feature( HB_GSUBHeader* gsub, + HB_UShort feature_index, + HB_UInt property ) +{ + HB_UShort i; + + HB_Feature feature; + HB_UInt* properties; + HB_UShort* index; + HB_UShort lookup_count; + + /* Each feature can only be added once */ + + if ( !gsub || + feature_index >= gsub->FeatureList.FeatureCount || + gsub->FeatureList.ApplyCount == gsub->FeatureList.FeatureCount ) + return ERR(HB_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++ ) + { + HB_UShort lookup_index = index[i]; + if (lookup_index < lookup_count) + properties[lookup_index] |= property; + } + + return HB_Err_Ok; +} + + + +HB_Error HB_GSUB_Clear_Features( HB_GSUBHeader* gsub ) +{ + HB_UShort i; + + HB_UInt* properties; + + + if ( !gsub ) + return ERR(HB_Err_Invalid_Argument); + + gsub->FeatureList.ApplyCount = 0; + + properties = gsub->LookupList.Properties; + + for ( i = 0; i < gsub->LookupList.LookupCount; i++ ) + properties[i] = 0; + + return HB_Err_Ok; +} + + + +HB_Error HB_GSUB_Register_Alternate_Function( HB_GSUBHeader* gsub, + HB_AltFunction altfunc, + void* data ) +{ + if ( !gsub ) + return ERR(HB_Err_Invalid_Argument); + + gsub->altfunc = altfunc; + gsub->data = data; + + return HB_Err_Ok; +} + +/* returns error if one happened, otherwise returns HB_Err_Not_Covered if no + * feature were applied, or HB_Err_Ok otherwise. + */ +HB_Error HB_GSUB_Apply_String( HB_GSUBHeader* gsub, + HB_Buffer buffer ) +{ + HB_Error error, retError = HB_Err_Not_Covered; + int i, j, lookup_count, num_features; + + if ( !gsub || + !buffer) + return ERR(HB_Err_Invalid_Argument); + + if ( buffer->in_length == 0 ) + return retError; + + lookup_count = gsub->LookupList.LookupCount; + num_features = gsub->FeatureList.ApplyCount; + + for ( i = 0; i < num_features; i++) + { + HB_UShort feature_index = gsub->FeatureList.ApplyOrder[i]; + HB_Feature feature = gsub->FeatureList.FeatureRecord[feature_index].Feature; + + for ( j = 0; j < feature.LookupListCount; j++ ) + { + HB_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 != HB_Err_Not_Covered ) + return error; + } + else + retError = error; + } + } + + error = retError; + + return error; +} + + +/* END */ |