932 lines
23 KiB
C++
932 lines
23 KiB
C++
/*
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* Copyright (C) 2007,2008,2009,2010 Red Hat, Inc.
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* Copyright (C) 2010 Google, Inc.
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*
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* This is part of HarfBuzz, a text shaping library.
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*
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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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*
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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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* DAMAGE.
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*
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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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*
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* Red Hat Author(s): Behdad Esfahbod
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* Google Author(s): Behdad Esfahbod
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*/
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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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HB_BEGIN_DECLS
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struct SingleSubstFormat1
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{
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friend struct SingleSubst;
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private:
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inline bool apply (hb_apply_context_t *c) const
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{
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TRACE_APPLY ();
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hb_codepoint_t glyph_id = c->buffer->info[c->buffer->i].codepoint;
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unsigned int index = (this+coverage) (glyph_id);
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if (likely (index == NOT_COVERED))
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return false;
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glyph_id += deltaGlyphID;
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c->replace_glyph (glyph_id);
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return true;
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}
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inline bool sanitize (hb_sanitize_context_t *c) {
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TRACE_SANITIZE ();
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return coverage.sanitize (c, this)
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&& deltaGlyphID.sanitize (c);
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}
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private:
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USHORT format; /* Format identifier--format = 1 */
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OffsetTo<Coverage>
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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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public:
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DEFINE_SIZE_STATIC (6);
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};
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struct SingleSubstFormat2
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{
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friend struct SingleSubst;
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private:
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inline bool apply (hb_apply_context_t *c) const
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{
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TRACE_APPLY ();
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hb_codepoint_t glyph_id = c->buffer->info[c->buffer->i].codepoint;
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unsigned int index = (this+coverage) (glyph_id);
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if (likely (index == NOT_COVERED))
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return false;
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if (unlikely (index >= substitute.len))
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return false;
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glyph_id = substitute[index];
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c->replace_glyph (glyph_id);
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return true;
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}
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inline bool sanitize (hb_sanitize_context_t *c) {
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TRACE_SANITIZE ();
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return coverage.sanitize (c, this)
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&& substitute.sanitize (c);
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}
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private:
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USHORT format; /* Format identifier--format = 2 */
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OffsetTo<Coverage>
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coverage; /* Offset to Coverage table--from
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* beginning of Substitution table */
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ArrayOf<GlyphID>
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substitute; /* Array of substitute
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* GlyphIDs--ordered by Coverage Index */
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public:
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DEFINE_SIZE_ARRAY (6, substitute);
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};
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struct SingleSubst
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{
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friend struct SubstLookupSubTable;
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private:
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inline bool apply (hb_apply_context_t *c) const
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{
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TRACE_APPLY ();
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switch (u.format) {
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case 1: return u.format1.apply (c);
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case 2: return u.format2.apply (c);
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default:return false;
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}
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}
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inline bool sanitize (hb_sanitize_context_t *c) {
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TRACE_SANITIZE ();
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if (!u.format.sanitize (c)) return false;
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switch (u.format) {
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case 1: return u.format1.sanitize (c);
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case 2: return u.format2.sanitize (c);
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default:return true;
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}
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}
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private:
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union {
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USHORT format; /* Format identifier */
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SingleSubstFormat1 format1;
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SingleSubstFormat2 format2;
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} u;
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};
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struct Sequence
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{
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friend struct MultipleSubstFormat1;
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private:
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inline bool apply (hb_apply_context_t *c) const
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{
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TRACE_APPLY ();
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if (unlikely (!substitute.len))
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return false;
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if (c->property & HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE)
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c->guess_glyph_class (HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH);
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c->replace_glyphs_be16 (1, substitute.len, (const uint16_t *) substitute.array);
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return true;
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}
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public:
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inline bool sanitize (hb_sanitize_context_t *c) {
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TRACE_SANITIZE ();
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return substitute.sanitize (c);
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}
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private:
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ArrayOf<GlyphID>
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substitute; /* String of GlyphIDs to substitute */
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public:
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DEFINE_SIZE_ARRAY (2, substitute);
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};
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struct MultipleSubstFormat1
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{
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friend struct MultipleSubst;
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private:
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inline bool apply (hb_apply_context_t *c) const
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{
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TRACE_APPLY ();
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unsigned int index = (this+coverage) (c->buffer->info[c->buffer->i].codepoint);
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if (likely (index == NOT_COVERED))
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return false;
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return (this+sequence[index]).apply (c);
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}
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inline bool sanitize (hb_sanitize_context_t *c) {
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TRACE_SANITIZE ();
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return coverage.sanitize (c, this)
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&& sequence.sanitize (c, this);
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}
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private:
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USHORT format; /* Format identifier--format = 1 */
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OffsetTo<Coverage>
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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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public:
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DEFINE_SIZE_ARRAY (6, sequence);
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};
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struct MultipleSubst
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{
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friend struct SubstLookupSubTable;
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private:
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inline bool apply (hb_apply_context_t *c) const
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{
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TRACE_APPLY ();
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switch (u.format) {
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case 1: return u.format1.apply (c);
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default:return false;
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}
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}
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inline bool sanitize (hb_sanitize_context_t *c) {
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TRACE_SANITIZE ();
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if (!u.format.sanitize (c)) return false;
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switch (u.format) {
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case 1: return u.format1.sanitize (c);
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default:return true;
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}
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}
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private:
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union {
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USHORT format; /* Format identifier */
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MultipleSubstFormat1 format1;
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} u;
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};
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typedef ArrayOf<GlyphID> AlternateSet; /* Array of alternate GlyphIDs--in
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* arbitrary order */
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struct AlternateSubstFormat1
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{
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friend struct AlternateSubst;
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private:
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inline bool apply (hb_apply_context_t *c) const
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{
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TRACE_APPLY ();
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hb_codepoint_t glyph_id = c->buffer->info[c->buffer->i].codepoint;
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hb_mask_t glyph_mask = c->buffer->info[c->buffer->i].mask;
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hb_mask_t lookup_mask = c->lookup_mask;
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unsigned int index = (this+coverage) (glyph_id);
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if (likely (index == NOT_COVERED))
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return false;
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const AlternateSet &alt_set = this+alternateSet[index];
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if (unlikely (!alt_set.len))
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return false;
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/* Note: This breaks badly if two features enabled this lookup together. */
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unsigned int shift = _hb_ctz (lookup_mask);
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unsigned int alt_index = ((lookup_mask & glyph_mask) >> shift);
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if (unlikely (alt_index > alt_set.len || alt_index == 0))
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return false;
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glyph_id = alt_set[alt_index - 1];
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c->replace_glyph (glyph_id);
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return true;
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}
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inline bool sanitize (hb_sanitize_context_t *c) {
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TRACE_SANITIZE ();
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return coverage.sanitize (c, this)
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&& alternateSet.sanitize (c, this);
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}
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private:
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USHORT format; /* Format identifier--format = 1 */
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OffsetTo<Coverage>
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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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public:
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DEFINE_SIZE_ARRAY (6, alternateSet);
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};
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struct AlternateSubst
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{
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friend struct SubstLookupSubTable;
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private:
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inline bool apply (hb_apply_context_t *c) const
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{
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TRACE_APPLY ();
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switch (u.format) {
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case 1: return u.format1.apply (c);
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default:return false;
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}
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}
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inline bool sanitize (hb_sanitize_context_t *c) {
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TRACE_SANITIZE ();
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if (!u.format.sanitize (c)) return false;
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switch (u.format) {
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case 1: return u.format1.sanitize (c);
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default:return true;
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}
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}
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private:
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union {
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USHORT format; /* Format identifier */
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AlternateSubstFormat1 format1;
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} u;
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};
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struct Ligature
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{
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friend struct LigatureSet;
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private:
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inline bool apply (hb_apply_context_t *c) const
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{
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TRACE_APPLY ();
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unsigned int i, j;
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unsigned int count = component.len;
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unsigned int end = MIN (c->buffer->len, c->buffer->i + c->context_length);
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if (unlikely (count < 2 || c->buffer->i + count > end))
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return false;
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bool first_was_mark = (c->property & HB_OT_LAYOUT_GLYPH_CLASS_MARK);
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bool found_non_mark = false;
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for (i = 1, j = c->buffer->i + 1; i < count; i++, j++)
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{
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unsigned int property;
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while (_hb_ot_layout_skip_mark (c->layout->face, &c->buffer->info[j], c->lookup_props, &property))
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{
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if (unlikely (j + count - i == end))
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return false;
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j++;
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}
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found_non_mark |= !(property & HB_OT_LAYOUT_GLYPH_CLASS_MARK);
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if (likely (c->buffer->info[j].codepoint != component[i]))
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return false;
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}
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if (first_was_mark && found_non_mark)
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c->guess_glyph_class (HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE);
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/* Allocate new ligature id */
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unsigned int lig_id = allocate_lig_id (c->buffer);
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c->buffer->info[c->buffer->i].lig_comp() = 0;
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c->buffer->info[c->buffer->i].lig_id() = lig_id;
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if (j == c->buffer->i + i) /* No input glyphs skipped */
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{
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c->replace_glyphs_be16 (i, 1, (const uint16_t *) &ligGlyph);
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}
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else
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{
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c->replace_glyph (ligGlyph);
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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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{
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while (_hb_ot_layout_skip_mark (c->layout->face, &c->buffer->info[c->buffer->i], c->lookup_props, NULL))
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{
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c->buffer->info[c->buffer->i].lig_comp() = i;
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c->buffer->info[c->buffer->i].lig_id() = lig_id;
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c->replace_glyph (c->buffer->info[c->buffer->i].codepoint);
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}
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/* Skip the base glyph */
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c->buffer->i++;
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}
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}
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return true;
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}
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inline uint16_t allocate_lig_id (hb_buffer_t *buffer) const {
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uint16_t lig_id = buffer->next_serial ();
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if (unlikely (!lig_id)) lig_id = buffer->next_serial (); /* in case of overflows */
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return lig_id;
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}
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public:
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inline bool sanitize (hb_sanitize_context_t *c) {
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TRACE_SANITIZE ();
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return ligGlyph.sanitize (c)
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&& component.sanitize (c);
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}
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private:
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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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public:
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DEFINE_SIZE_ARRAY (4, component);
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};
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struct LigatureSet
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{
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friend struct LigatureSubstFormat1;
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private:
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inline bool apply (hb_apply_context_t *c) const
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{
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TRACE_APPLY ();
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unsigned int num_ligs = ligature.len;
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for (unsigned int i = 0; i < num_ligs; i++)
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{
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const Ligature &lig = this+ligature[i];
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if (lig.apply (c))
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return true;
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}
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return false;
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}
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public:
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inline bool sanitize (hb_sanitize_context_t *c) {
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TRACE_SANITIZE ();
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return ligature.sanitize (c, this);
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}
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private:
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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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public:
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DEFINE_SIZE_ARRAY (2, ligature);
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};
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struct LigatureSubstFormat1
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{
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friend struct LigatureSubst;
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private:
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inline bool apply (hb_apply_context_t *c) const
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{
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TRACE_APPLY ();
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hb_codepoint_t glyph_id = c->buffer->info[c->buffer->i].codepoint;
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unsigned int index = (this+coverage) (glyph_id);
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if (likely (index == NOT_COVERED))
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return false;
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const LigatureSet &lig_set = this+ligatureSet[index];
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return lig_set.apply (c);
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}
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inline bool sanitize (hb_sanitize_context_t *c) {
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TRACE_SANITIZE ();
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return coverage.sanitize (c, this)
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&& ligatureSet.sanitize (c, this);
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}
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|
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private:
|
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USHORT format; /* Format identifier--format = 1 */
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OffsetTo<Coverage>
|
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coverage; /* Offset to Coverage table--from
|
|
* 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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public:
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DEFINE_SIZE_ARRAY (6, ligatureSet);
|
|
};
|
|
|
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struct LigatureSubst
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{
|
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friend struct SubstLookupSubTable;
|
|
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private:
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inline bool apply (hb_apply_context_t *c) const
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{
|
|
TRACE_APPLY ();
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switch (u.format) {
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case 1: return u.format1.apply (c);
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default:return false;
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}
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|
}
|
|
|
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inline bool sanitize (hb_sanitize_context_t *c) {
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TRACE_SANITIZE ();
|
|
if (!u.format.sanitize (c)) return false;
|
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switch (u.format) {
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case 1: return u.format1.sanitize (c);
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default:return true;
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}
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}
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|
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private:
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union {
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USHORT format; /* Format identifier */
|
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LigatureSubstFormat1 format1;
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} u;
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};
|
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|
|
|
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HB_BEGIN_DECLS
|
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static inline bool substitute_lookup (hb_apply_context_t *c, unsigned int lookup_index);
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HB_END_DECLS
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|
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struct ContextSubst : Context
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{
|
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friend struct SubstLookupSubTable;
|
|
|
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private:
|
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inline bool apply (hb_apply_context_t *c) const
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|
{
|
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TRACE_APPLY ();
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return Context::apply (c, substitute_lookup);
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}
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|
};
|
|
|
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struct ChainContextSubst : ChainContext
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|
{
|
|
friend struct SubstLookupSubTable;
|
|
|
|
private:
|
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inline bool apply (hb_apply_context_t *c) const
|
|
{
|
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TRACE_APPLY ();
|
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return ChainContext::apply (c, substitute_lookup);
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|
}
|
|
};
|
|
|
|
|
|
struct ExtensionSubst : Extension
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|
{
|
|
friend struct SubstLookupSubTable;
|
|
friend struct SubstLookup;
|
|
|
|
private:
|
|
inline const struct SubstLookupSubTable& get_subtable (void) const
|
|
{
|
|
unsigned int offset = get_offset ();
|
|
if (unlikely (!offset)) return Null(SubstLookupSubTable);
|
|
return StructAtOffset<SubstLookupSubTable> (this, offset);
|
|
}
|
|
|
|
inline bool apply (hb_apply_context_t *c) const;
|
|
|
|
inline bool sanitize (hb_sanitize_context_t *c);
|
|
|
|
inline bool is_reverse (void) const;
|
|
};
|
|
|
|
|
|
struct ReverseChainSingleSubstFormat1
|
|
{
|
|
friend struct ReverseChainSingleSubst;
|
|
|
|
private:
|
|
inline bool apply (hb_apply_context_t *c) const
|
|
{
|
|
TRACE_APPLY ();
|
|
if (unlikely (c->context_length != NO_CONTEXT))
|
|
return false; /* No chaining to this type */
|
|
|
|
unsigned int index = (this+coverage) (c->buffer->info[c->buffer->i].codepoint);
|
|
if (likely (index == NOT_COVERED))
|
|
return false;
|
|
|
|
const OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack);
|
|
const ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead);
|
|
|
|
if (match_backtrack (c,
|
|
backtrack.len, (USHORT *) backtrack.array,
|
|
match_coverage, this) &&
|
|
match_lookahead (c,
|
|
lookahead.len, (USHORT *) lookahead.array,
|
|
match_coverage, this,
|
|
1))
|
|
{
|
|
c->buffer->info[c->buffer->i].codepoint = substitute[index];
|
|
c->buffer->i--; /* Reverse! */
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
inline bool sanitize (hb_sanitize_context_t *c) {
|
|
TRACE_SANITIZE ();
|
|
if (!(coverage.sanitize (c, this)
|
|
&& backtrack.sanitize (c, this)))
|
|
return false;
|
|
OffsetArrayOf<Coverage> &lookahead = StructAfter<OffsetArrayOf<Coverage> > (backtrack);
|
|
if (!lookahead.sanitize (c, this))
|
|
return false;
|
|
ArrayOf<GlyphID> &substitute = StructAfter<ArrayOf<GlyphID> > (lookahead);
|
|
return substitute.sanitize (c);
|
|
}
|
|
|
|
private:
|
|
USHORT format; /* Format identifier--format = 1 */
|
|
OffsetTo<Coverage>
|
|
coverage; /* Offset to Coverage table--from
|
|
* beginning of table */
|
|
OffsetArrayOf<Coverage>
|
|
backtrack; /* Array of coverage tables
|
|
* in backtracking sequence, in glyph
|
|
* sequence order */
|
|
OffsetArrayOf<Coverage>
|
|
lookaheadX; /* Array of coverage tables
|
|
* in lookahead sequence, in glyph
|
|
* sequence order */
|
|
ArrayOf<GlyphID>
|
|
substituteX; /* Array of substitute
|
|
* GlyphIDs--ordered by Coverage Index */
|
|
public:
|
|
DEFINE_SIZE_MIN (10);
|
|
};
|
|
|
|
struct ReverseChainSingleSubst
|
|
{
|
|
friend struct SubstLookupSubTable;
|
|
|
|
private:
|
|
inline bool apply (hb_apply_context_t *c) const
|
|
{
|
|
TRACE_APPLY ();
|
|
switch (u.format) {
|
|
case 1: return u.format1.apply (c);
|
|
default:return false;
|
|
}
|
|
}
|
|
|
|
inline bool sanitize (hb_sanitize_context_t *c) {
|
|
TRACE_SANITIZE ();
|
|
if (!u.format.sanitize (c)) return false;
|
|
switch (u.format) {
|
|
case 1: return u.format1.sanitize (c);
|
|
default:return true;
|
|
}
|
|
}
|
|
|
|
private:
|
|
union {
|
|
USHORT format; /* Format identifier */
|
|
ReverseChainSingleSubstFormat1 format1;
|
|
} u;
|
|
};
|
|
|
|
|
|
|
|
/*
|
|
* SubstLookup
|
|
*/
|
|
|
|
struct SubstLookupSubTable
|
|
{
|
|
friend struct SubstLookup;
|
|
|
|
enum {
|
|
Single = 1,
|
|
Multiple = 2,
|
|
Alternate = 3,
|
|
Ligature = 4,
|
|
Context = 5,
|
|
ChainContext = 6,
|
|
Extension = 7,
|
|
ReverseChainSingle = 8
|
|
};
|
|
|
|
inline bool apply (hb_apply_context_t *c, unsigned int lookup_type) const
|
|
{
|
|
TRACE_APPLY ();
|
|
switch (lookup_type) {
|
|
case Single: return u.single.apply (c);
|
|
case Multiple: return u.multiple.apply (c);
|
|
case Alternate: return u.alternate.apply (c);
|
|
case Ligature: return u.ligature.apply (c);
|
|
case Context: return u.c.apply (c);
|
|
case ChainContext: return u.chainContext.apply (c);
|
|
case Extension: return u.extension.apply (c);
|
|
case ReverseChainSingle: return u.reverseChainContextSingle.apply (c);
|
|
default:return false;
|
|
}
|
|
}
|
|
|
|
inline bool sanitize (hb_sanitize_context_t *c, unsigned int lookup_type) {
|
|
TRACE_SANITIZE ();
|
|
switch (lookup_type) {
|
|
case Single: return u.single.sanitize (c);
|
|
case Multiple: return u.multiple.sanitize (c);
|
|
case Alternate: return u.alternate.sanitize (c);
|
|
case Ligature: return u.ligature.sanitize (c);
|
|
case Context: return u.c.sanitize (c);
|
|
case ChainContext: return u.chainContext.sanitize (c);
|
|
case Extension: return u.extension.sanitize (c);
|
|
case ReverseChainSingle: return u.reverseChainContextSingle.sanitize (c);
|
|
default:return true;
|
|
}
|
|
}
|
|
|
|
private:
|
|
union {
|
|
USHORT sub_format;
|
|
SingleSubst single;
|
|
MultipleSubst multiple;
|
|
AlternateSubst alternate;
|
|
LigatureSubst ligature;
|
|
ContextSubst c;
|
|
ChainContextSubst chainContext;
|
|
ExtensionSubst extension;
|
|
ReverseChainSingleSubst reverseChainContextSingle;
|
|
} u;
|
|
public:
|
|
DEFINE_SIZE_UNION (2, sub_format);
|
|
};
|
|
|
|
|
|
struct SubstLookup : Lookup
|
|
{
|
|
inline const SubstLookupSubTable& get_subtable (unsigned int i) const
|
|
{ return this+CastR<OffsetArrayOf<SubstLookupSubTable> > (subTable)[i]; }
|
|
|
|
inline static bool lookup_type_is_reverse (unsigned int lookup_type)
|
|
{ return lookup_type == SubstLookupSubTable::ReverseChainSingle; }
|
|
|
|
inline bool is_reverse (void) const
|
|
{
|
|
unsigned int type = get_type ();
|
|
if (unlikely (type == SubstLookupSubTable::Extension))
|
|
return CastR<ExtensionSubst> (get_subtable(0)).is_reverse ();
|
|
return lookup_type_is_reverse (type);
|
|
}
|
|
|
|
|
|
inline bool apply_once (hb_ot_layout_context_t *layout,
|
|
hb_buffer_t *buffer,
|
|
hb_mask_t lookup_mask,
|
|
unsigned int context_length,
|
|
unsigned int nesting_level_left) const
|
|
{
|
|
unsigned int lookup_type = get_type ();
|
|
hb_apply_context_t c[1] = {{0}};
|
|
|
|
c->layout = layout;
|
|
c->buffer = buffer;
|
|
c->lookup_mask = lookup_mask;
|
|
c->context_length = context_length;
|
|
c->nesting_level_left = nesting_level_left;
|
|
c->lookup_props = get_props ();
|
|
|
|
if (!_hb_ot_layout_check_glyph_property (c->layout->face, &c->buffer->info[c->buffer->i], c->lookup_props, &c->property))
|
|
return false;
|
|
|
|
if (unlikely (lookup_type == SubstLookupSubTable::Extension))
|
|
{
|
|
/* The spec says all subtables should have the same type.
|
|
* This is specially important if one has a reverse type!
|
|
*
|
|
* This is rather slow to do this here for every glyph,
|
|
* but it's easiest, and who uses extension lookups anyway?!*/
|
|
unsigned int count = get_subtable_count ();
|
|
unsigned int type = get_subtable(0).u.extension.get_type ();
|
|
for (unsigned int i = 1; i < count; i++)
|
|
if (get_subtable(i).u.extension.get_type () != type)
|
|
return false;
|
|
}
|
|
|
|
unsigned int count = get_subtable_count ();
|
|
for (unsigned int i = 0; i < count; i++)
|
|
if (get_subtable (i).apply (c, lookup_type))
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
inline bool apply_string (hb_ot_layout_context_t *layout,
|
|
hb_buffer_t *buffer,
|
|
hb_mask_t mask) const
|
|
{
|
|
bool ret = false;
|
|
|
|
if (unlikely (!buffer->len))
|
|
return false;
|
|
|
|
if (likely (!is_reverse ()))
|
|
{
|
|
/* in/out forward substitution */
|
|
buffer->clear_output ();
|
|
buffer->i = 0;
|
|
while (buffer->i < buffer->len)
|
|
{
|
|
if ((buffer->info[buffer->i].mask & mask) &&
|
|
apply_once (layout, buffer, mask, NO_CONTEXT, MAX_NESTING_LEVEL))
|
|
ret = true;
|
|
else
|
|
buffer->next_glyph ();
|
|
|
|
}
|
|
if (ret)
|
|
buffer->swap ();
|
|
}
|
|
else
|
|
{
|
|
/* in-place backward substitution */
|
|
buffer->i = buffer->len - 1;
|
|
do
|
|
{
|
|
if ((buffer->info[buffer->i].mask & mask) &&
|
|
apply_once (layout, buffer, mask, NO_CONTEXT, MAX_NESTING_LEVEL))
|
|
ret = true;
|
|
else
|
|
buffer->i--;
|
|
|
|
}
|
|
while ((int) buffer->i >= 0);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
inline bool sanitize (hb_sanitize_context_t *c) {
|
|
TRACE_SANITIZE ();
|
|
if (unlikely (!Lookup::sanitize (c))) return false;
|
|
OffsetArrayOf<SubstLookupSubTable> &list = CastR<OffsetArrayOf<SubstLookupSubTable> > (subTable);
|
|
return list.sanitize (c, this, get_type ());
|
|
}
|
|
};
|
|
|
|
typedef OffsetListOf<SubstLookup> SubstLookupList;
|
|
|
|
/*
|
|
* GSUB
|
|
*/
|
|
|
|
struct GSUB : GSUBGPOS
|
|
{
|
|
static const hb_tag_t Tag = HB_OT_TAG_GSUB;
|
|
|
|
inline const SubstLookup& get_lookup (unsigned int i) const
|
|
{ return CastR<SubstLookup> (GSUBGPOS::get_lookup (i)); }
|
|
|
|
inline bool substitute_lookup (hb_ot_layout_context_t *layout,
|
|
hb_buffer_t *buffer,
|
|
unsigned int lookup_index,
|
|
hb_mask_t mask) const
|
|
{ return get_lookup (lookup_index).apply_string (layout, buffer, mask); }
|
|
|
|
inline bool sanitize (hb_sanitize_context_t *c) {
|
|
TRACE_SANITIZE ();
|
|
if (unlikely (!GSUBGPOS::sanitize (c))) return false;
|
|
OffsetTo<SubstLookupList> &list = CastR<OffsetTo<SubstLookupList> > (lookupList);
|
|
return list.sanitize (c, this);
|
|
}
|
|
public:
|
|
DEFINE_SIZE_STATIC (10);
|
|
};
|
|
|
|
|
|
/* Out-of-class implementation for methods recursing */
|
|
|
|
inline bool ExtensionSubst::apply (hb_apply_context_t *c) const
|
|
{
|
|
TRACE_APPLY ();
|
|
return get_subtable ().apply (c, get_type ());
|
|
}
|
|
|
|
inline bool ExtensionSubst::sanitize (hb_sanitize_context_t *c)
|
|
{
|
|
TRACE_SANITIZE ();
|
|
if (unlikely (!Extension::sanitize (c))) return false;
|
|
unsigned int offset = get_offset ();
|
|
if (unlikely (!offset)) return true;
|
|
return StructAtOffset<SubstLookupSubTable> (this, offset).sanitize (c, get_type ());
|
|
}
|
|
|
|
inline bool ExtensionSubst::is_reverse (void) const
|
|
{
|
|
unsigned int type = get_type ();
|
|
if (unlikely (type == SubstLookupSubTable::Extension))
|
|
return CastR<ExtensionSubst> (get_subtable()).is_reverse ();
|
|
return SubstLookup::lookup_type_is_reverse (type);
|
|
}
|
|
|
|
static inline bool substitute_lookup (hb_apply_context_t *c, unsigned int lookup_index)
|
|
{
|
|
const GSUB &gsub = *(c->layout->face->ot_layout->gsub);
|
|
const SubstLookup &l = gsub.get_lookup (lookup_index);
|
|
|
|
if (unlikely (c->nesting_level_left == 0))
|
|
return false;
|
|
|
|
if (unlikely (c->context_length < 1))
|
|
return false;
|
|
|
|
return l.apply_once (c->layout, c->buffer, c->lookup_mask, c->context_length, c->nesting_level_left - 1);
|
|
}
|
|
|
|
|
|
HB_END_DECLS
|
|
|
|
#endif /* HB_OT_LAYOUT_GSUB_PRIVATE_HH */
|