Branch
Hash :
8bdedb3b
Author :
Date :
2025-08-20T00:27:41
Limit external caches (#5483) * Revert "[external_cache] Remove a conditional (#5471)" This reverts commit 9794ad9e00ff66741c36ec9511e3e968663b74a7. * Limit external_cache to 8 subtables per lookup
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195
#ifndef OT_LAYOUT_GSUB_LIGATURESUBSTFORMAT1_HH
#define OT_LAYOUT_GSUB_LIGATURESUBSTFORMAT1_HH
#include "Common.hh"
#include "LigatureSet.hh"
namespace OT {
namespace Layout {
namespace GSUB_impl {
template <typename Types>
struct LigatureSubstFormat1_2
{
protected:
HBUINT16 format; /* Format identifier--format = 1 */
typename Types::template OffsetTo<Coverage>
coverage; /* Offset to Coverage table--from
* beginning of Substitution table */
Array16Of<typename Types::template OffsetTo<LigatureSet<Types>>>
ligatureSet; /* Array LigatureSet tables
* ordered by Coverage Index */
public:
DEFINE_SIZE_ARRAY (4 + Types::size, ligatureSet);
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (coverage.sanitize (c, this) && ligatureSet.sanitize (c, this));
}
bool intersects (const hb_set_t *glyphs) const
{
return
+ hb_zip (this+coverage, ligatureSet)
| hb_filter (*glyphs, hb_first)
| hb_map (hb_second)
| hb_map ([this, glyphs] (const typename Types::template OffsetTo<LigatureSet<Types>> &_)
{ return (this+_).intersects (glyphs); })
| hb_any
;
}
bool may_have_non_1to1 () const
{ return true; }
void closure (hb_closure_context_t *c) const
{
+ hb_zip (this+coverage, ligatureSet)
| hb_filter (c->parent_active_glyphs (), hb_first)
| hb_map (hb_second)
| hb_map (hb_add (this))
| hb_apply ([c] (const LigatureSet<Types> &_) { _.closure (c); })
;
}
void closure_lookups (hb_closure_lookups_context_t *c) const {}
void collect_glyphs (hb_collect_glyphs_context_t *c) const
{
if (unlikely (!(this+coverage).collect_coverage (c->input))) return;
+ hb_zip (this+coverage, ligatureSet)
| hb_map (hb_second)
| hb_map (hb_add (this))
| hb_apply ([c] (const LigatureSet<Types> &_) { _.collect_glyphs (c); })
;
}
const Coverage &get_coverage () const { return this+coverage; }
bool would_apply (hb_would_apply_context_t *c) const
{
unsigned int index = (this+coverage).get_coverage (c->glyphs[0]);
if (likely (index == NOT_COVERED)) return false;
const auto &lig_set = this+ligatureSet[index];
return lig_set.would_apply (c);
}
struct external_cache_t
{
hb_ot_layout_mapping_cache_t coverage;
hb_set_digest_t seconds;
};
void *external_cache_create () const
{
external_cache_t *cache = (external_cache_t *) hb_malloc (sizeof (external_cache_t));
if (likely (cache))
{
cache->coverage.clear ();
cache->seconds.init ();
+ hb_iter (ligatureSet)
| hb_map (hb_add (this))
| hb_apply ([cache] (const LigatureSet<Types> &_) { _.collect_seconds (cache->seconds); })
;
}
return cache;
}
bool apply (hb_ot_apply_context_t *c, void *external_cache) const
{
TRACE_APPLY (this);
hb_buffer_t *buffer = c->buffer;
#ifndef HB_NO_OT_LAYOUT_LOOKUP_CACHE
external_cache_t *cache = (external_cache_t *) external_cache;
const hb_set_digest_t *seconds = cache ? &cache->seconds : nullptr;
unsigned int index = (this+coverage).get_coverage (buffer->cur().codepoint, cache ? &cache->coverage : nullptr);
#else
const hb_set_digest_t *seconds = nullptr;
unsigned int index = (this+coverage).get_coverage (buffer->cur().codepoint);
#endif
if (index == NOT_COVERED) return_trace (false);
const auto &lig_set = this+ligatureSet[index];
return_trace (lig_set.apply (c, seconds));
}
bool serialize (hb_serialize_context_t *c,
hb_sorted_array_t<const HBGlyphID16> first_glyphs,
hb_array_t<const unsigned int> ligature_per_first_glyph_count_list,
hb_array_t<const HBGlyphID16> ligatures_list,
hb_array_t<const unsigned int> component_count_list,
hb_array_t<const HBGlyphID16> component_list /* Starting from second for each ligature */)
{
TRACE_SERIALIZE (this);
if (unlikely (!c->extend_min (this))) return_trace (false);
if (unlikely (!ligatureSet.serialize (c, first_glyphs.length))) return_trace (false);
for (unsigned int i = 0; i < first_glyphs.length; i++)
{
unsigned int ligature_count = ligature_per_first_glyph_count_list[i];
if (unlikely (!ligatureSet[i]
.serialize_serialize (c,
ligatures_list.sub_array (0, ligature_count),
component_count_list.sub_array (0, ligature_count),
component_list))) return_trace (false);
ligatures_list += ligature_count;
component_count_list += ligature_count;
}
return_trace (coverage.serialize_serialize (c, first_glyphs));
}
bool subset (hb_subset_context_t *c) const
{
TRACE_SUBSET (this);
const hb_set_t &glyphset = *c->plan->glyphset_gsub ();
const hb_map_t &glyph_map = *c->plan->glyph_map;
auto *out = c->serializer->start_embed (*this);
if (unlikely (!c->serializer->extend_min (out))) return_trace (false);
out->format = format;
// Due to a bug in some older versions of windows 7 the Coverage table must be
// packed after the LigatureSet and Ligature tables, so serialize Coverage first
// which places it last in the packed order.
hb_set_t new_coverage;
+ hb_zip (this+coverage, hb_iter (ligatureSet) | hb_map (hb_add (this)))
| hb_filter (glyphset, hb_first)
| hb_filter ([&] (const LigatureSet<Types>& _) {
return _.intersects_lig_glyph (&glyphset);
}, hb_second)
| hb_map (hb_first)
| hb_sink (new_coverage);
if (!c->serializer->push<Coverage> ()
->serialize (c->serializer,
+ new_coverage.iter () | hb_map_retains_sorting (glyph_map)))
{
c->serializer->pop_discard ();
return_trace (false);
}
unsigned coverage_idx = c->serializer->pop_pack ();
c->serializer->add_link (out->coverage, coverage_idx);
+ hb_zip (this+coverage, ligatureSet)
| hb_filter (new_coverage, hb_first)
| hb_map (hb_second)
// to ensure that the repacker always orders the coverage table after the LigatureSet
// and LigatureSubtable's they will be linked to the Coverage table via a virtual link
// the coverage table object idx is passed down to facilitate this.
| hb_apply (subset_offset_array (c, out->ligatureSet, this, coverage_idx))
;
return_trace (bool (new_coverage));
}
};
}
}
}
#endif /* OT_LAYOUT_GSUB_LIGATURESUBSTFORMAT1_HH */