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* Copyright (C) 2007,2008,2009 Red Hat, Inc.
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* This is part of HarfBuzz, an OpenType Layout engine library.
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* Permission is hereby granted, without written agreement and without
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* license or royalty fees, to use, copy, modify, and distribute this
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* software and its documentation for any purpose, provided that the
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* above copyright notice and the following two paragraphs appear in
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* all copies of this software.
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* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
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* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
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* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
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* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
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* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
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* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
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* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
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* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
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* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
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* Red Hat Author(s): Behdad Esfahbod
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#ifndef HB_OT_LAYOUT_GSUB_PRIVATE_HH
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#define HB_OT_LAYOUT_GSUB_PRIVATE_HH
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#include "hb-ot-layout-gsubgpos-private.hh"
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struct SingleSubstFormat1
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friend struct SingleSubst;
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inline bool apply (APPLY_ARG_DEF) const
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hb_codepoint_t glyph_id = IN_CURGLYPH ();
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unsigned int index = (this+coverage) (glyph_id);
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if (HB_LIKELY (index == NOT_COVERED))
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glyph_id += deltaGlyphID;
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_hb_buffer_replace_glyph (buffer, glyph_id);
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/* We inherit the old glyph class to the substituted glyph */
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if (_hb_ot_layout_has_new_glyph_classes (context->face))
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_hb_ot_layout_set_glyph_property (context->face, glyph_id, property);
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inline bool sanitize (SANITIZE_ARG_DEF) {
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return SANITIZE_THIS (coverage) && SANITIZE (deltaGlyphID);
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USHORT format; /* Format identifier--format = 1 */
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coverage; /* Offset to Coverage table--from
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* beginning of Substitution table */
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SHORT deltaGlyphID; /* Add to original GlyphID to get
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* substitute GlyphID */
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ASSERT_SIZE (SingleSubstFormat1, 6);
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struct SingleSubstFormat2
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friend struct SingleSubst;
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inline bool apply (APPLY_ARG_DEF) const
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hb_codepoint_t glyph_id = IN_CURGLYPH ();
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unsigned int index = (this+coverage) (glyph_id);
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if (HB_LIKELY (index == NOT_COVERED))
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if (HB_UNLIKELY (index >= substitute.len))
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glyph_id = substitute[index];
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_hb_buffer_replace_glyph (buffer, glyph_id);
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/* We inherit the old glyph class to the substituted glyph */
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if (_hb_ot_layout_has_new_glyph_classes (context->face))
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_hb_ot_layout_set_glyph_property (context->face, glyph_id, property);
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inline bool sanitize (SANITIZE_ARG_DEF) {
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return SANITIZE_THIS (coverage) && SANITIZE (substitute);
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USHORT format; /* Format identifier--format = 2 */
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coverage; /* Offset to Coverage table--from
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* beginning of Substitution table */
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substitute; /* Array of substitute
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* GlyphIDs--ordered by Coverage Index */
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ASSERT_SIZE (SingleSubstFormat2, 6);
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friend struct SubstLookupSubTable;
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inline bool apply (APPLY_ARG_DEF) const
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case 1: return u.format1->apply (APPLY_ARG);
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case 2: return u.format2->apply (APPLY_ARG);
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default:return false;
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inline bool sanitize (SANITIZE_ARG_DEF) {
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if (!SANITIZE (u.format)) return false;
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case 1: return u.format1->sanitize (SANITIZE_ARG);
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case 2: return u.format2->sanitize (SANITIZE_ARG);
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USHORT format; /* Format identifier */
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SingleSubstFormat1 format1[];
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SingleSubstFormat2 format2[];
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ASSERT_SIZE (SingleSubst, 2);
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friend struct MultipleSubstFormat1;
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inline bool apply (APPLY_ARG_DEF) const
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if (HB_UNLIKELY (!substitute.len))
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_hb_buffer_add_output_glyphs (buffer, 1,
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substitute.len, (const uint16_t *) substitute.array,
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/* This is a guess only ... */
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if (_hb_ot_layout_has_new_glyph_classes (context->face))
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if (property == HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE)
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property = HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH;
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unsigned int count = substitute.len;
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for (unsigned int n = 0; n < count; n++)
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_hb_ot_layout_set_glyph_property (context->face, substitute[n], property);
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inline bool sanitize (SANITIZE_ARG_DEF) {
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return SANITIZE (substitute);
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substitute; /* String of GlyphIDs to substitute */
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ASSERT_SIZE (Sequence, 2);
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struct MultipleSubstFormat1
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friend struct MultipleSubst;
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inline bool apply (APPLY_ARG_DEF) const
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unsigned int index = (this+coverage) (IN_CURGLYPH ());
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if (HB_LIKELY (index == NOT_COVERED))
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return (this+sequence[index]).apply (APPLY_ARG);
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inline bool sanitize (SANITIZE_ARG_DEF) {
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return SANITIZE_THIS2 (coverage, sequence);
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USHORT format; /* Format identifier--format = 1 */
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coverage; /* Offset to Coverage table--from
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* beginning of Substitution table */
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OffsetArrayOf<Sequence>
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sequence; /* Array of Sequence tables
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* ordered by Coverage Index */
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ASSERT_SIZE (MultipleSubstFormat1, 6);
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friend struct SubstLookupSubTable;
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inline bool apply (APPLY_ARG_DEF) const
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case 1: return u.format1->apply (APPLY_ARG);
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default:return false;
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inline bool sanitize (SANITIZE_ARG_DEF) {
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if (!SANITIZE (u.format)) return false;
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case 1: return u.format1->sanitize (SANITIZE_ARG);
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USHORT format; /* Format identifier */
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MultipleSubstFormat1 format1[];
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ASSERT_SIZE (MultipleSubst, 2);
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typedef ArrayOf<GlyphID> AlternateSet; /* Array of alternate GlyphIDs--in
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ASSERT_SIZE (AlternateSet, 2);
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struct AlternateSubstFormat1
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friend struct AlternateSubst;
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inline bool apply (APPLY_ARG_DEF) const
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hb_codepoint_t glyph_id = IN_CURGLYPH ();
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unsigned int index = (this+coverage) (glyph_id);
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if (HB_LIKELY (index == NOT_COVERED))
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const AlternateSet &alt_set = this+alternateSet[index];
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if (HB_UNLIKELY (!alt_set.len))
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unsigned int alt_index = 0;
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/* XXX callback to user to choose alternate
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if (context->face->altfunc)
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alt_index = (context->face->altfunc)(context->layout, buffer,
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buffer->out_pos, glyph_id,
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alt_set.len, alt_set.array);
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if (HB_UNLIKELY (alt_index >= alt_set.len))
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glyph_id = alt_set[alt_index];
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_hb_buffer_replace_glyph (buffer, glyph_id);
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/* We inherit the old glyph class to the substituted glyph */
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if (_hb_ot_layout_has_new_glyph_classes (context->face))
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_hb_ot_layout_set_glyph_property (context->face, glyph_id, property);
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inline bool sanitize (SANITIZE_ARG_DEF) {
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return SANITIZE_THIS2 (coverage, alternateSet);
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USHORT format; /* Format identifier--format = 1 */
313
coverage; /* Offset to Coverage table--from
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* beginning of Substitution table */
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OffsetArrayOf<AlternateSet>
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alternateSet; /* Array of AlternateSet tables
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* ordered by Coverage Index */
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ASSERT_SIZE (AlternateSubstFormat1, 6);
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struct AlternateSubst
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friend struct SubstLookupSubTable;
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inline bool apply (APPLY_ARG_DEF) const
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case 1: return u.format1->apply (APPLY_ARG);
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default:return false;
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inline bool sanitize (SANITIZE_ARG_DEF) {
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if (!SANITIZE (u.format)) return false;
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case 1: return u.format1->sanitize (SANITIZE_ARG);
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USHORT format; /* Format identifier */
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AlternateSubstFormat1 format1[];
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ASSERT_SIZE (AlternateSubst, 2);
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friend struct LigatureSet;
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inline bool apply (APPLY_ARG_DEF, bool is_mark) const
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unsigned int count = component.len;
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unsigned int end = MIN (buffer->in_length, buffer->in_pos + context_length);
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if (HB_UNLIKELY (buffer->in_pos + count > end))
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for (i = 1, j = buffer->in_pos + 1; i < count; i++, j++)
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while (_hb_ot_layout_skip_mark (context->face, IN_INFO (j), lookup_flag, &property))
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if (HB_UNLIKELY (j + count - i == end))
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if (!(property & HB_OT_LAYOUT_GLYPH_CLASS_MARK))
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if (HB_LIKELY (IN_GLYPH (j) != component[i]))
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/* This is just a guess ... */
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if (_hb_ot_layout_has_new_glyph_classes (context->face))
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_hb_ot_layout_set_glyph_class (context->face, ligGlyph,
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is_mark ? HB_OT_LAYOUT_GLYPH_CLASS_MARK
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: HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE);
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if (j == buffer->in_pos + i) /* No input glyphs skipped */
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/* We don't use a new ligature ID if there are no skipped
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glyphs and the ligature already has an ID. */
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_hb_buffer_add_output_glyphs (buffer, i,
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1, (const uint16_t *) &ligGlyph,
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IN_LIGID (buffer->in_pos) ?
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0xFFFF : _hb_buffer_allocate_lig_id (buffer));
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unsigned int lig_id = _hb_buffer_allocate_lig_id (buffer);
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_hb_buffer_add_output_glyph (buffer, ligGlyph, 0xFFFF, lig_id);
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/* Now we must do a second loop to copy the skipped glyphs to
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`out' and assign component values to it. We start with the
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glyph after the first component. Glyphs between component
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i and i+1 belong to component i. Together with the lig_id
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value it is later possible to check whether a specific
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component value really belongs to a given ligature. */
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for ( i = 1; i < count; i++ )
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while (_hb_ot_layout_skip_mark (context->face, IN_CURINFO (), lookup_flag, NULL))
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_hb_buffer_add_output_glyph (buffer, IN_CURGLYPH (), i - 1, lig_id);
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/* TODO We should possibly reassign lig_id and component for any
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* components of a previous ligature that s now being removed as part of
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inline bool sanitize (SANITIZE_ARG_DEF) {
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return SANITIZE2 (ligGlyph, component);
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GlyphID ligGlyph; /* GlyphID of ligature to substitute */
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HeadlessArrayOf<GlyphID>
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component; /* Array of component GlyphIDs--start
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* with the second component--ordered
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* in writing direction */
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ASSERT_SIZE (Ligature, 4);
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friend struct LigatureSubstFormat1;
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inline bool apply (APPLY_ARG_DEF, bool is_mark) const
448
unsigned int num_ligs = ligature.len;
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for (unsigned int i = 0; i < num_ligs; i++)
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const Ligature &lig = this+ligature[i];
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if (lig.apply (APPLY_ARG, is_mark))
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inline bool sanitize (SANITIZE_ARG_DEF) {
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return SANITIZE_THIS (ligature);
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OffsetArrayOf<Ligature>
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ligature; /* Array LigatureSet tables
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* ordered by preference */
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ASSERT_SIZE (LigatureSet, 2);
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struct LigatureSubstFormat1
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friend struct LigatureSubst;
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inline bool apply (APPLY_ARG_DEF) const
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hb_codepoint_t glyph_id = IN_CURGLYPH ();
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bool first_is_mark = !!(property & HB_OT_LAYOUT_GLYPH_CLASS_MARK);
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unsigned int index = (this+coverage) (glyph_id);
485
if (HB_LIKELY (index == NOT_COVERED))
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const LigatureSet &lig_set = this+ligatureSet[index];
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return lig_set.apply (APPLY_ARG, first_is_mark);
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inline bool sanitize (SANITIZE_ARG_DEF) {
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return SANITIZE_THIS2 (coverage, ligatureSet);
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USHORT format; /* Format identifier--format = 1 */
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coverage; /* Offset to Coverage table--from
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* beginning of Substitution table */
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OffsetArrayOf<LigatureSet>
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ligatureSet; /* Array LigatureSet tables
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* ordered by Coverage Index */
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ASSERT_SIZE (LigatureSubstFormat1, 6);
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friend struct SubstLookupSubTable;
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inline bool apply (APPLY_ARG_DEF) const
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case 1: return u.format1->apply (APPLY_ARG);
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default:return false;
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inline bool sanitize (SANITIZE_ARG_DEF) {
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if (!SANITIZE (u.format)) return false;
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case 1: return u.format1->sanitize (SANITIZE_ARG);
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USHORT format; /* Format identifier */
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LigatureSubstFormat1 format1[];
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ASSERT_SIZE (LigatureSubst, 2);
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static inline bool substitute_lookup (APPLY_ARG_DEF, unsigned int lookup_index);
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struct ContextSubst : Context
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friend struct SubstLookupSubTable;
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inline bool apply (APPLY_ARG_DEF) const
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return Context::apply (APPLY_ARG, substitute_lookup);
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ASSERT_SIZE (ContextSubst, 2);
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struct ChainContextSubst : ChainContext
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friend struct SubstLookupSubTable;
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inline bool apply (APPLY_ARG_DEF) const
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return ChainContext::apply (APPLY_ARG, substitute_lookup);
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ASSERT_SIZE (ChainContextSubst, 2);
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struct ExtensionSubst : Extension
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friend struct SubstLookupSubTable;
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inline const struct SubstLookupSubTable& get_subtable (void) const
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{ return CONST_CAST (SubstLookupSubTable, Extension::get_subtable (), 0); }
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inline bool apply (APPLY_ARG_DEF) const;
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inline bool sanitize (SANITIZE_ARG_DEF);
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ASSERT_SIZE (ExtensionSubst, 2);
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struct ReverseChainSingleSubstFormat1
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friend struct ReverseChainSingleSubst;
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inline bool apply (APPLY_ARG_DEF) const
593
if (HB_UNLIKELY (context_length != NO_CONTEXT))
594
return false; /* No chaining to this type */
596
unsigned int index = (this+coverage) (IN_CURGLYPH ());
597
if (HB_LIKELY (index == NOT_COVERED))
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const OffsetArrayOf<Coverage> &lookahead = CONST_NEXT (OffsetArrayOf<Coverage>, backtrack);
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const ArrayOf<GlyphID> &substitute = CONST_NEXT (ArrayOf<GlyphID>, lookahead);
603
if (match_backtrack (APPLY_ARG,
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backtrack.len, (USHORT *) backtrack.array,
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match_coverage, DECONST_CHARP(this)) &&
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match_lookahead (APPLY_ARG,
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lookahead.len, (USHORT *) lookahead.array,
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match_coverage, DECONST_CHARP(this),
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IN_CURGLYPH () = substitute[index];
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buffer->in_pos--; /* Reverse! */
619
inline bool sanitize (SANITIZE_ARG_DEF) {
621
if (!SANITIZE_THIS2 (coverage, backtrack))
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OffsetArrayOf<Coverage> &lookahead = NEXT (OffsetArrayOf<Coverage>, backtrack);
624
if (!SANITIZE_THIS (lookahead))
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ArrayOf<GlyphID> &substitute = NEXT (ArrayOf<GlyphID>, lookahead);
627
return SANITIZE (substitute);
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USHORT format; /* Format identifier--format = 1 */
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coverage; /* Offset to Coverage table--from
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* beginning of table */
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OffsetArrayOf<Coverage>
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backtrack; /* Array of coverage tables
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* in backtracking sequence, in glyph
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OffsetArrayOf<Coverage>
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lookaheadX; /* Array of coverage tables
641
* in lookahead sequence, in glyph
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substituteX; /* Array of substitute
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* GlyphIDs--ordered by Coverage Index */
647
ASSERT_SIZE (ReverseChainSingleSubstFormat1, 10);
649
struct ReverseChainSingleSubst
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friend struct SubstLookupSubTable;
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inline bool apply (APPLY_ARG_DEF) const
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case 1: return u.format1->apply (APPLY_ARG);
659
default:return false;
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inline bool sanitize (SANITIZE_ARG_DEF) {
665
if (!SANITIZE (u.format)) return false;
667
case 1: return u.format1->sanitize (SANITIZE_ARG);
674
USHORT format; /* Format identifier */
675
ReverseChainSingleSubstFormat1 format1[];
678
ASSERT_SIZE (ReverseChainSingleSubst, 2);
686
struct SubstLookupSubTable
688
friend struct SubstLookup;
698
ReverseChainSingle = 8
701
inline bool apply (APPLY_ARG_DEF, unsigned int lookup_type) const
704
switch (lookup_type) {
705
case Single: return u.single->apply (APPLY_ARG);
706
case Multiple: return u.multiple->apply (APPLY_ARG);
707
case Alternate: return u.alternate->apply (APPLY_ARG);
708
case Ligature: return u.ligature->apply (APPLY_ARG);
709
case Context: return u.context->apply (APPLY_ARG);
710
case ChainContext: return u.chainContext->apply (APPLY_ARG);
711
case Extension: return u.extension->apply (APPLY_ARG);
712
case ReverseChainSingle: return u.reverseChainContextSingle->apply (APPLY_ARG);
713
default:return false;
717
inline bool sanitize (SANITIZE_ARG_DEF) {
719
if (!SANITIZE (u.format)) return false;
721
case Single: return u.single->sanitize (SANITIZE_ARG);
722
case Multiple: return u.multiple->sanitize (SANITIZE_ARG);
723
case Alternate: return u.alternate->sanitize (SANITIZE_ARG);
724
case Ligature: return u.ligature->sanitize (SANITIZE_ARG);
725
case Context: return u.context->sanitize (SANITIZE_ARG);
726
case ChainContext: return u.chainContext->sanitize (SANITIZE_ARG);
727
case Extension: return u.extension->sanitize (SANITIZE_ARG);
728
case ReverseChainSingle: return u.reverseChainContextSingle->sanitize (SANITIZE_ARG);
736
SingleSubst single[];
737
MultipleSubst multiple[];
738
AlternateSubst alternate[];
739
LigatureSubst ligature[];
740
ContextSubst context[];
741
ChainContextSubst chainContext[];
742
ExtensionSubst extension[];
743
ReverseChainSingleSubst reverseChainContextSingle[];
746
ASSERT_SIZE (SubstLookupSubTable, 2);
749
struct SubstLookup : Lookup
751
inline const SubstLookupSubTable& get_subtable (unsigned int i) const
752
{ return CONST_CAST (SubstLookupSubTable, Lookup::get_subtable (i), 0); }
754
/* Like get_type(), but looks through extension lookups.
755
* Never returns Extension */
756
inline unsigned int get_effective_type (void) const
758
unsigned int type = get_type ();
760
if (HB_UNLIKELY (type == SubstLookupSubTable::Extension))
762
unsigned int count = get_subtable_count ();
763
type = get_subtable(0).u.extension->get_type ();
764
/* The spec says all subtables should have the same type.
765
* This is specially important if one has a reverse type! */
766
for (unsigned int i = 1; i < count; i++)
767
if (get_subtable(i).u.extension->get_type () != type)
774
inline bool is_reverse (void) const
775
{ return HB_UNLIKELY (get_effective_type () == SubstLookupSubTable::ReverseChainSingle); }
777
inline bool apply_once (hb_ot_layout_context_t *context,
779
unsigned int context_length,
780
unsigned int nesting_level_left) const
782
unsigned int lookup_type = get_type ();
783
unsigned int lookup_flag = get_flag ();
784
unsigned int property;
786
if (!_hb_ot_layout_check_glyph_property (context->face, IN_CURINFO (), lookup_flag, &property))
789
unsigned int count = get_subtable_count ();
790
for (unsigned int i = 0; i < count; i++)
791
if (get_subtable (i).apply (APPLY_ARG_INIT, lookup_type))
797
inline bool apply_string (hb_ot_layout_context_t *context,
799
hb_mask_t mask) const
803
if (HB_UNLIKELY (!buffer->in_length))
806
if (HB_LIKELY (!is_reverse ()))
808
/* in/out forward substitution */
809
_hb_buffer_clear_output (buffer);
811
while (buffer->in_pos < buffer->in_length)
813
if ((~IN_MASK (buffer->in_pos) & mask) &&
814
apply_once (context, buffer, NO_CONTEXT, MAX_NESTING_LEVEL))
817
_hb_buffer_next_glyph (buffer);
821
_hb_buffer_swap (buffer);
825
/* in-place backward substitution */
826
buffer->in_pos = buffer->in_length - 1;
829
if ((~IN_MASK (buffer->in_pos) & mask) &&
830
apply_once (context, buffer, NO_CONTEXT, MAX_NESTING_LEVEL))
836
while ((int) buffer->in_pos >= 0);
842
inline bool sanitize (SANITIZE_ARG_DEF) {
844
if (!Lookup::sanitize (SANITIZE_ARG)) return false;
845
OffsetArrayOf<SubstLookupSubTable> &list = (OffsetArrayOf<SubstLookupSubTable> &) subTable;
846
return SANITIZE_THIS (list);
849
ASSERT_SIZE (SubstLookup, 6);
851
typedef OffsetListOf<SubstLookup> SubstLookupList;
852
ASSERT_SIZE (SubstLookupList, 2);
858
struct GSUB : GSUBGPOS
860
static const hb_tag_t Tag = HB_OT_TAG_GSUB;
862
static inline const GSUB& get_for_data (const char *data)
863
{ return (const GSUB&) GSUBGPOS::get_for_data (data); }
865
inline const SubstLookup& get_lookup (unsigned int i) const
866
{ return (const SubstLookup&) GSUBGPOS::get_lookup (i); }
868
inline bool substitute_lookup (hb_ot_layout_context_t *context,
870
unsigned int lookup_index,
871
hb_mask_t mask) const
872
{ return get_lookup (lookup_index).apply_string (context, buffer, mask); }
875
inline bool sanitize (SANITIZE_ARG_DEF) {
877
if (!GSUBGPOS::sanitize (SANITIZE_ARG)) return false;
878
OffsetTo<SubstLookupList> &list = CAST(OffsetTo<SubstLookupList>, lookupList, 0);
879
return SANITIZE_THIS (list);
882
ASSERT_SIZE (GSUB, 10);
885
/* Out-of-class implementation for methods recursing */
887
inline bool ExtensionSubst::apply (APPLY_ARG_DEF) const
890
unsigned int lookup_type = get_type ();
892
if (HB_UNLIKELY (lookup_type == SubstLookupSubTable::Extension))
895
return get_subtable ().apply (APPLY_ARG, lookup_type);
898
inline bool ExtensionSubst::sanitize (SANITIZE_ARG_DEF)
901
return Extension::sanitize (SANITIZE_ARG) &&
902
(&(Extension::get_subtable ()) == &Null(LookupSubTable) ||
903
get_type () == SubstLookupSubTable::Extension ||
904
DECONST_CAST (SubstLookupSubTable, get_subtable (), 0).sanitize (SANITIZE_ARG));
907
static inline bool substitute_lookup (APPLY_ARG_DEF, unsigned int lookup_index)
909
const GSUB &gsub = *(context->face->ot_layout.gsub);
910
const SubstLookup &l = gsub.get_lookup (lookup_index);
912
if (HB_UNLIKELY (nesting_level_left == 0))
914
nesting_level_left--;
916
if (HB_UNLIKELY (context_length < 1))
919
return l.apply_once (context, buffer, context_length, nesting_level_left);
923
#endif /* HB_OT_LAYOUT_GSUB_PRIVATE_HH */