/pango-1.30.0/pango/opentype/hb-ot-layout-gsub-private.hh
C++ Header | 909 lines | 665 code | 167 blank | 77 comment | 89 complexity | 1d9d25bce77a774018e301339b68a4fe MD5 | raw file
Possible License(s): LGPL-2.0
- /*
- * Copyright (C) 2007,2008,2009 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
- */
- #ifndef HB_OT_LAYOUT_GSUB_PRIVATE_HH
- #define HB_OT_LAYOUT_GSUB_PRIVATE_HH
- #include "hb-ot-layout-gsubgpos-private.hh"
- struct SingleSubstFormat1
- {
- friend struct SingleSubst;
- private:
- inline bool apply (APPLY_ARG_DEF) const
- {
- TRACE_APPLY ();
- hb_codepoint_t glyph_id = IN_CURGLYPH ();
- unsigned int index = (this+coverage) (glyph_id);
- if (HB_LIKELY (index == NOT_COVERED))
- return false;
- glyph_id += deltaGlyphID;
- _hb_buffer_replace_glyph (buffer, glyph_id);
- /* We inherit the old glyph class to the substituted glyph */
- if (_hb_ot_layout_has_new_glyph_classes (context->face))
- _hb_ot_layout_set_glyph_property (context->face, glyph_id, property);
- return true;
- }
- inline bool sanitize (SANITIZE_ARG_DEF) {
- TRACE_SANITIZE ();
- return SANITIZE_THIS (coverage) && SANITIZE (deltaGlyphID);
- }
- private:
- USHORT format; /* Format identifier--format = 1 */
- OffsetTo<Coverage>
- coverage; /* Offset to Coverage table--from
- * beginning of Substitution table */
- SHORT deltaGlyphID; /* Add to original GlyphID to get
- * substitute GlyphID */
- };
- ASSERT_SIZE (SingleSubstFormat1, 6);
- struct SingleSubstFormat2
- {
- friend struct SingleSubst;
- private:
- inline bool apply (APPLY_ARG_DEF) const
- {
- TRACE_APPLY ();
- hb_codepoint_t glyph_id = IN_CURGLYPH ();
- unsigned int index = (this+coverage) (glyph_id);
- if (HB_LIKELY (index == NOT_COVERED))
- return false;
- if (HB_UNLIKELY (index >= substitute.len))
- return false;
- glyph_id = substitute[index];
- _hb_buffer_replace_glyph (buffer, glyph_id);
- /* We inherit the old glyph class to the substituted glyph */
- if (_hb_ot_layout_has_new_glyph_classes (context->face))
- _hb_ot_layout_set_glyph_property (context->face, glyph_id, property);
- return true;
- }
- inline bool sanitize (SANITIZE_ARG_DEF) {
- TRACE_SANITIZE ();
- return SANITIZE_THIS (coverage) && SANITIZE (substitute);
- }
- private:
- USHORT format; /* Format identifier--format = 2 */
- OffsetTo<Coverage>
- coverage; /* Offset to Coverage table--from
- * beginning of Substitution table */
- ArrayOf<GlyphID>
- substitute; /* Array of substitute
- * GlyphIDs--ordered by Coverage Index */
- };
- ASSERT_SIZE (SingleSubstFormat2, 6);
- struct SingleSubst
- {
- friend struct SubstLookupSubTable;
- private:
- inline bool apply (APPLY_ARG_DEF) const
- {
- TRACE_APPLY ();
- switch (u.format) {
- case 1: return u.format1->apply (APPLY_ARG);
- case 2: return u.format2->apply (APPLY_ARG);
- default:return false;
- }
- }
- inline bool sanitize (SANITIZE_ARG_DEF) {
- TRACE_SANITIZE ();
- if (!SANITIZE (u.format)) return false;
- switch (u.format) {
- case 1: return u.format1->sanitize (SANITIZE_ARG);
- case 2: return u.format2->sanitize (SANITIZE_ARG);
- default:return true;
- }
- }
- private:
- union {
- USHORT format; /* Format identifier */
- SingleSubstFormat1 format1[VAR];
- SingleSubstFormat2 format2[VAR];
- } u;
- };
- struct Sequence
- {
- friend struct MultipleSubstFormat1;
- private:
- inline bool apply (APPLY_ARG_DEF) const
- {
- TRACE_APPLY ();
- if (HB_UNLIKELY (!substitute.len))
- return false;
- _hb_buffer_add_output_glyphs (buffer, 1,
- substitute.len, (const uint16_t *) substitute.const_array(),
- 0xFFFF, 0xFFFF);
- /* This is a guess only ... */
- if (_hb_ot_layout_has_new_glyph_classes (context->face))
- {
- if (property == HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE)
- property = HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH;
- unsigned int count = substitute.len;
- for (unsigned int n = 0; n < count; n++)
- _hb_ot_layout_set_glyph_property (context->face, substitute[n], property);
- }
- return true;
- }
- public:
- inline bool sanitize (SANITIZE_ARG_DEF) {
- TRACE_SANITIZE ();
- return SANITIZE (substitute);
- }
- private:
- ArrayOf<GlyphID>
- substitute; /* String of GlyphIDs to substitute */
- };
- ASSERT_SIZE (Sequence, 2);
- struct MultipleSubstFormat1
- {
- friend struct MultipleSubst;
- private:
- inline bool apply (APPLY_ARG_DEF) const
- {
- TRACE_APPLY ();
- unsigned int index = (this+coverage) (IN_CURGLYPH ());
- if (HB_LIKELY (index == NOT_COVERED))
- return false;
- return (this+sequence[index]).apply (APPLY_ARG);
- }
- inline bool sanitize (SANITIZE_ARG_DEF) {
- TRACE_SANITIZE ();
- return SANITIZE_THIS2 (coverage, sequence);
- }
- private:
- USHORT format; /* Format identifier--format = 1 */
- OffsetTo<Coverage>
- coverage; /* Offset to Coverage table--from
- * beginning of Substitution table */
- OffsetArrayOf<Sequence>
- sequence; /* Array of Sequence tables
- * ordered by Coverage Index */
- };
- ASSERT_SIZE (MultipleSubstFormat1, 6);
- struct MultipleSubst
- {
- friend struct SubstLookupSubTable;
- private:
- inline bool apply (APPLY_ARG_DEF) const
- {
- TRACE_APPLY ();
- switch (u.format) {
- case 1: return u.format1->apply (APPLY_ARG);
- default:return false;
- }
- }
- inline bool sanitize (SANITIZE_ARG_DEF) {
- TRACE_SANITIZE ();
- if (!SANITIZE (u.format)) return false;
- switch (u.format) {
- case 1: return u.format1->sanitize (SANITIZE_ARG);
- default:return true;
- }
- }
- private:
- union {
- USHORT format; /* Format identifier */
- MultipleSubstFormat1 format1[VAR];
- } u;
- };
- typedef ArrayOf<GlyphID> AlternateSet; /* Array of alternate GlyphIDs--in
- * arbitrary order */
- ASSERT_SIZE (AlternateSet, 2);
- struct AlternateSubstFormat1
- {
- friend struct AlternateSubst;
- private:
- inline bool apply (APPLY_ARG_DEF) const
- {
- TRACE_APPLY ();
- hb_codepoint_t glyph_id = IN_CURGLYPH ();
- unsigned int index = (this+coverage) (glyph_id);
- if (HB_LIKELY (index == NOT_COVERED))
- return false;
- const AlternateSet &alt_set = this+alternateSet[index];
- if (HB_UNLIKELY (!alt_set.len))
- return false;
- unsigned int alt_index = 0;
- /* XXX callback to user to choose alternate
- if (context->face->altfunc)
- alt_index = (context->face->altfunc)(context->layout, buffer,
- buffer->out_pos, glyph_id,
- alt_set.len, alt_set.array);
- */
- if (HB_UNLIKELY (alt_index >= alt_set.len))
- return false;
- glyph_id = alt_set[alt_index];
- _hb_buffer_replace_glyph (buffer, glyph_id);
- /* We inherit the old glyph class to the substituted glyph */
- if (_hb_ot_layout_has_new_glyph_classes (context->face))
- _hb_ot_layout_set_glyph_property (context->face, glyph_id, property);
- return true;
- }
- inline bool sanitize (SANITIZE_ARG_DEF) {
- TRACE_SANITIZE ();
- return SANITIZE_THIS2 (coverage, alternateSet);
- }
- private:
- USHORT format; /* Format identifier--format = 1 */
- OffsetTo<Coverage>
- coverage; /* Offset to Coverage table--from
- * beginning of Substitution table */
- OffsetArrayOf<AlternateSet>
- alternateSet; /* Array of AlternateSet tables
- * ordered by Coverage Index */
- };
- ASSERT_SIZE (AlternateSubstFormat1, 6);
- struct AlternateSubst
- {
- friend struct SubstLookupSubTable;
- private:
- inline bool apply (APPLY_ARG_DEF) const
- {
- TRACE_APPLY ();
- switch (u.format) {
- case 1: return u.format1->apply (APPLY_ARG);
- default:return false;
- }
- }
- inline bool sanitize (SANITIZE_ARG_DEF) {
- TRACE_SANITIZE ();
- if (!SANITIZE (u.format)) return false;
- switch (u.format) {
- case 1: return u.format1->sanitize (SANITIZE_ARG);
- default:return true;
- }
- }
- private:
- union {
- USHORT format; /* Format identifier */
- AlternateSubstFormat1 format1[VAR];
- } u;
- };
- struct Ligature
- {
- friend struct LigatureSet;
- private:
- inline bool apply (APPLY_ARG_DEF, bool is_mark) const
- {
- TRACE_APPLY ();
- unsigned int i, j;
- unsigned int count = component.len;
- unsigned int end = MIN (buffer->in_length, buffer->in_pos + context_length);
- if (HB_UNLIKELY (buffer->in_pos + count > end))
- return false;
- for (i = 1, j = buffer->in_pos + 1; i < count; i++, j++)
- {
- while (_hb_ot_layout_skip_mark (context->face, IN_INFO (j), lookup_flag, &property))
- {
- if (HB_UNLIKELY (j + count - i == end))
- return false;
- j++;
- }
- if (!(property & HB_OT_LAYOUT_GLYPH_CLASS_MARK))
- is_mark = FALSE;
- if (HB_LIKELY (IN_GLYPH (j) != component[i]))
- return false;
- }
- /* This is just a guess ... */
- if (_hb_ot_layout_has_new_glyph_classes (context->face))
- _hb_ot_layout_set_glyph_class (context->face, ligGlyph,
- is_mark ? HB_OT_LAYOUT_GLYPH_CLASS_MARK
- : HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE);
- 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. */
- _hb_buffer_add_output_glyphs (buffer, i,
- 1, (const uint16_t *) &ligGlyph,
- 0,
- IN_LIGID (buffer->in_pos) && !IN_COMPONENT (buffer->in_pos) ?
- 0xFFFF : _hb_buffer_allocate_lig_id (buffer));
- else
- {
- unsigned int lig_id = _hb_buffer_allocate_lig_id (buffer);
- _hb_buffer_add_output_glyph (buffer, ligGlyph, 0xFFFF, lig_id);
- /* 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 lig_id
- value it is later possible to check whether a specific
- component value really belongs to a given ligature. */
- for ( i = 1; i < count; i++ )
- {
- while (_hb_ot_layout_skip_mark (context->face, IN_CURINFO (), lookup_flag, NULL))
- _hb_buffer_add_output_glyph (buffer, IN_CURGLYPH (), i, lig_id);
- (buffer->in_pos)++;
- }
- }
- return true;
- }
- public:
- inline bool sanitize (SANITIZE_ARG_DEF) {
- TRACE_SANITIZE ();
- return SANITIZE2 (ligGlyph, component);
- }
- private:
- GlyphID ligGlyph; /* GlyphID of ligature to substitute */
- HeadlessArrayOf<GlyphID>
- component; /* Array of component GlyphIDs--start
- * with the second component--ordered
- * in writing direction */
- };
- ASSERT_SIZE (Ligature, 4);
- struct LigatureSet
- {
- friend struct LigatureSubstFormat1;
- private:
- inline bool apply (APPLY_ARG_DEF, bool is_mark) const
- {
- TRACE_APPLY ();
- unsigned int num_ligs = ligature.len;
- for (unsigned int i = 0; i < num_ligs; i++)
- {
- const Ligature &lig = this+ligature[i];
- if (lig.apply (APPLY_ARG, is_mark))
- return true;
- }
- return false;
- }
- public:
- inline bool sanitize (SANITIZE_ARG_DEF) {
- TRACE_SANITIZE ();
- return SANITIZE_THIS (ligature);
- }
- private:
- OffsetArrayOf<Ligature>
- ligature; /* Array LigatureSet tables
- * ordered by preference */
- };
- ASSERT_SIZE (LigatureSet, 2);
- struct LigatureSubstFormat1
- {
- friend struct LigatureSubst;
- private:
- inline bool apply (APPLY_ARG_DEF) const
- {
- TRACE_APPLY ();
- hb_codepoint_t glyph_id = IN_CURGLYPH ();
- bool first_is_mark = !!(property & HB_OT_LAYOUT_GLYPH_CLASS_MARK);
- unsigned int index = (this+coverage) (glyph_id);
- if (HB_LIKELY (index == NOT_COVERED))
- return false;
- const LigatureSet &lig_set = this+ligatureSet[index];
- return lig_set.apply (APPLY_ARG, first_is_mark);
- }
- inline bool sanitize (SANITIZE_ARG_DEF) {
- TRACE_SANITIZE ();
- return SANITIZE_THIS2 (coverage, ligatureSet);
- }
- private:
- USHORT format; /* Format identifier--format = 1 */
- OffsetTo<Coverage>
- coverage; /* Offset to Coverage table--from
- * beginning of Substitution table */
- OffsetArrayOf<LigatureSet>
- ligatureSet; /* Array LigatureSet tables
- * ordered by Coverage Index */
- };
- ASSERT_SIZE (LigatureSubstFormat1, 6);
- struct LigatureSubst
- {
- friend struct SubstLookupSubTable;
- private:
- inline bool apply (APPLY_ARG_DEF) const
- {
- TRACE_APPLY ();
- switch (u.format) {
- case 1: return u.format1->apply (APPLY_ARG);
- default:return false;
- }
- }
- inline bool sanitize (SANITIZE_ARG_DEF) {
- TRACE_SANITIZE ();
- if (!SANITIZE (u.format)) return false;
- switch (u.format) {
- case 1: return u.format1->sanitize (SANITIZE_ARG);
- default:return true;
- }
- }
- private:
- union {
- USHORT format; /* Format identifier */
- LigatureSubstFormat1 format1[VAR];
- } u;
- };
- static inline bool substitute_lookup (APPLY_ARG_DEF, unsigned int lookup_index);
- struct ContextSubst : Context
- {
- friend struct SubstLookupSubTable;
- private:
- inline bool apply (APPLY_ARG_DEF) const
- {
- TRACE_APPLY ();
- return Context::apply (APPLY_ARG, substitute_lookup);
- }
- };
- struct ChainContextSubst : ChainContext
- {
- friend struct SubstLookupSubTable;
- private:
- inline bool apply (APPLY_ARG_DEF) const
- {
- TRACE_APPLY ();
- return ChainContext::apply (APPLY_ARG, substitute_lookup);
- }
- };
- struct ExtensionSubst : Extension
- {
- friend struct SubstLookupSubTable;
- private:
- inline const struct SubstLookupSubTable& get_subtable (void) const
- { return CONST_CAST (SubstLookupSubTable, Extension::get_subtable (), 0); }
- inline bool apply (APPLY_ARG_DEF) const;
- inline bool sanitize (SANITIZE_ARG_DEF);
- };
- struct ReverseChainSingleSubstFormat1
- {
- friend struct ReverseChainSingleSubst;
- private:
- inline bool apply (APPLY_ARG_DEF) const
- {
- TRACE_APPLY ();
- if (HB_UNLIKELY (context_length != NO_CONTEXT))
- return false; /* No chaining to this type */
- unsigned int index = (this+coverage) (IN_CURGLYPH ());
- if (HB_LIKELY (index == NOT_COVERED))
- return false;
- const OffsetArrayOf<Coverage> &lookahead = CONST_NEXT (OffsetArrayOf<Coverage>, backtrack);
- const ArrayOf<GlyphID> &substitute = CONST_NEXT (ArrayOf<GlyphID>, lookahead);
- if (match_backtrack (APPLY_ARG,
- backtrack.len, (USHORT *) backtrack.const_array(),
- match_coverage, DECONST_CHARP(this)) &&
- match_lookahead (APPLY_ARG,
- lookahead.len, (USHORT *) lookahead.const_array(),
- match_coverage, DECONST_CHARP(this),
- 1))
- {
- IN_CURGLYPH () = substitute[index];
- buffer->in_pos--; /* Reverse! */
- return true;
- }
- return false;
- }
- inline bool sanitize (SANITIZE_ARG_DEF) {
- TRACE_SANITIZE ();
- if (!SANITIZE_THIS2 (coverage, backtrack))
- return false;
- OffsetArrayOf<Coverage> &lookahead = NEXT (OffsetArrayOf<Coverage>, backtrack);
- if (!SANITIZE_THIS (lookahead))
- return false;
- ArrayOf<GlyphID> &substitute = NEXT (ArrayOf<GlyphID>, lookahead);
- return SANITIZE (substitute);
- }
- 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 */
- };
- ASSERT_SIZE (ReverseChainSingleSubstFormat1, 10);
- struct ReverseChainSingleSubst
- {
- friend struct SubstLookupSubTable;
- private:
- inline bool apply (APPLY_ARG_DEF) const
- {
- TRACE_APPLY ();
- switch (u.format) {
- case 1: return u.format1->apply (APPLY_ARG);
- default:return false;
- }
- }
- inline bool sanitize (SANITIZE_ARG_DEF) {
- TRACE_SANITIZE ();
- if (!SANITIZE (u.format)) return false;
- switch (u.format) {
- case 1: return u.format1->sanitize (SANITIZE_ARG);
- default:return true;
- }
- }
- private:
- union {
- USHORT format; /* Format identifier */
- ReverseChainSingleSubstFormat1 format1[VAR];
- } 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 (APPLY_ARG_DEF, unsigned int lookup_type) const
- {
- TRACE_APPLY ();
- switch (lookup_type) {
- case Single: return u.single->apply (APPLY_ARG);
- case Multiple: return u.multiple->apply (APPLY_ARG);
- case Alternate: return u.alternate->apply (APPLY_ARG);
- case Ligature: return u.ligature->apply (APPLY_ARG);
- case Context: return u.context->apply (APPLY_ARG);
- case ChainContext: return u.chainContext->apply (APPLY_ARG);
- case Extension: return u.extension->apply (APPLY_ARG);
- case ReverseChainSingle: return u.reverseChainContextSingle->apply (APPLY_ARG);
- default:return false;
- }
- }
- inline bool sanitize (SANITIZE_ARG_DEF, unsigned int lookup_type) {
- TRACE_SANITIZE ();
- if (!SANITIZE (u.sub_format)) return false;
- switch (lookup_type) {
- case Single: return u.single->sanitize (SANITIZE_ARG);
- case Multiple: return u.multiple->sanitize (SANITIZE_ARG);
- case Alternate: return u.alternate->sanitize (SANITIZE_ARG);
- case Ligature: return u.ligature->sanitize (SANITIZE_ARG);
- case Context: return u.context->sanitize (SANITIZE_ARG);
- case ChainContext: return u.chainContext->sanitize (SANITIZE_ARG);
- case Extension: return u.extension->sanitize (SANITIZE_ARG);
- case ReverseChainSingle: return u.reverseChainContextSingle->sanitize (SANITIZE_ARG);
- default:return true;
- }
- }
- private:
- union {
- USHORT sub_format;
- SingleSubst single[VAR];
- MultipleSubst multiple[VAR];
- AlternateSubst alternate[VAR];
- LigatureSubst ligature[VAR];
- ContextSubst context[VAR];
- ChainContextSubst chainContext[VAR];
- ExtensionSubst extension[VAR];
- ReverseChainSingleSubst reverseChainContextSingle[VAR];
- } u;
- };
- struct SubstLookup : Lookup
- {
- inline const SubstLookupSubTable& get_subtable (unsigned int i) const
- { return CONST_CAST (SubstLookupSubTable, Lookup::get_subtable (i), 0); }
- /* Like get_type(), but looks through extension lookups.
- * Never returns Extension */
- inline unsigned int get_effective_type (void) const
- {
- unsigned int type = get_type ();
- if (HB_UNLIKELY (type == SubstLookupSubTable::Extension))
- {
- unsigned int count = get_subtable_count ();
- type = get_subtable(0).u.extension->get_type ();
- /* The spec says all subtables should have the same type.
- * This is specially important if one has a reverse type! */
- for (unsigned int i = 1; i < count; i++)
- if (get_subtable(i).u.extension->get_type () != type)
- return 0;
- }
- return type;
- }
- inline bool is_reverse (void) const
- { return HB_UNLIKELY (get_effective_type () == SubstLookupSubTable::ReverseChainSingle); }
- inline bool apply_once (hb_ot_layout_context_t *context,
- hb_buffer_t *buffer,
- unsigned int context_length,
- unsigned int nesting_level_left) const
- {
- unsigned int lookup_type = get_type ();
- unsigned int lookup_flag = get_flag ();
- unsigned int property;
- if (!_hb_ot_layout_check_glyph_property (context->face, IN_CURINFO (), lookup_flag, &property))
- return false;
- unsigned int count = get_subtable_count ();
- for (unsigned int i = 0; i < count; i++)
- if (get_subtable (i).apply (APPLY_ARG_INIT, lookup_type))
- return true;
- return false;
- }
- inline bool apply_string (hb_ot_layout_context_t *context,
- hb_buffer_t *buffer,
- hb_mask_t mask) const
- {
- bool ret = false;
- if (HB_UNLIKELY (!buffer->in_length))
- return false;
- if (HB_LIKELY (!is_reverse ()))
- {
- /* in/out forward substitution */
- _hb_buffer_clear_output (buffer);
- buffer->in_pos = 0;
- while (buffer->in_pos < buffer->in_length)
- {
- if ((~IN_MASK (buffer->in_pos) & mask) &&
- apply_once (context, buffer, NO_CONTEXT, MAX_NESTING_LEVEL))
- ret = true;
- else
- _hb_buffer_next_glyph (buffer);
- }
- if (ret)
- _hb_buffer_swap (buffer);
- }
- else
- {
- /* in-place backward substitution */
- buffer->in_pos = buffer->in_length - 1;
- do
- {
- if ((~IN_MASK (buffer->in_pos) & mask) &&
- apply_once (context, buffer, NO_CONTEXT, MAX_NESTING_LEVEL))
- ret = true;
- else
- buffer->in_pos--;
- }
- while ((int) buffer->in_pos >= 0);
- }
- return ret;
- }
- inline bool sanitize (SANITIZE_ARG_DEF) {
- TRACE_SANITIZE ();
- if (!Lookup::sanitize (SANITIZE_ARG)) return false;
- OffsetArrayOf<SubstLookupSubTable> &list = (OffsetArrayOf<SubstLookupSubTable> &) subTable;
- return list.sanitize (SANITIZE_ARG, this, get_type ());
- }
- };
- typedef OffsetListOf<SubstLookup> SubstLookupList;
- ASSERT_SIZE (SubstLookupList, 2);
- /*
- * GSUB
- */
- struct GSUB : GSUBGPOS
- {
- static const hb_tag_t Tag = HB_OT_TAG_GSUB;
- static inline const GSUB& get_for_data (const char *data)
- { return (const GSUB&) GSUBGPOS::get_for_data (data); }
- inline const SubstLookup& get_lookup (unsigned int i) const
- { return (const SubstLookup&) GSUBGPOS::get_lookup (i); }
- inline bool substitute_lookup (hb_ot_layout_context_t *context,
- hb_buffer_t *buffer,
- unsigned int lookup_index,
- hb_mask_t mask) const
- { return get_lookup (lookup_index).apply_string (context, buffer, mask); }
- inline bool sanitize (SANITIZE_ARG_DEF) {
- TRACE_SANITIZE ();
- if (!GSUBGPOS::sanitize (SANITIZE_ARG)) return false;
- OffsetTo<SubstLookupList> &list = CAST(OffsetTo<SubstLookupList>, lookupList, 0);
- return SANITIZE_THIS (list);
- }
- };
- ASSERT_SIZE (GSUB, 10);
- /* Out-of-class implementation for methods recursing */
- inline bool ExtensionSubst::apply (APPLY_ARG_DEF) const
- {
- TRACE_APPLY ();
- unsigned int lookup_type = get_type ();
- if (HB_UNLIKELY (lookup_type == SubstLookupSubTable::Extension))
- return false;
- return get_subtable ().apply (APPLY_ARG, lookup_type);
- }
- inline bool ExtensionSubst::sanitize (SANITIZE_ARG_DEF)
- {
- TRACE_SANITIZE ();
- return Extension::sanitize (SANITIZE_ARG) &&
- (&(Extension::get_subtable ()) == &Null(LookupSubTable) ||
- get_type () == SubstLookupSubTable::Extension ||
- DECONST_CAST (SubstLookupSubTable, get_subtable (), 0).sanitize (SANITIZE_ARG, get_type ()));
- }
- static inline bool substitute_lookup (APPLY_ARG_DEF, unsigned int lookup_index)
- {
- const GSUB &gsub = *(context->face->ot_layout.gsub);
- const SubstLookup &l = gsub.get_lookup (lookup_index);
- if (HB_UNLIKELY (nesting_level_left == 0))
- return false;
- nesting_level_left--;
- if (HB_UNLIKELY (context_length < 1))
- return false;
- return l.apply_once (context, buffer, context_length, nesting_level_left);
- }
- #endif /* HB_OT_LAYOUT_GSUB_PRIVATE_HH */