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Diffstat (limited to 'gfx/harfbuzz/src/OT/Layout/GSUB/SingleSubstFormat1.hh')
| -rw-r--r-- | gfx/harfbuzz/src/OT/Layout/GSUB/SingleSubstFormat1.hh | 204 |
1 files changed, 204 insertions, 0 deletions
diff --git a/gfx/harfbuzz/src/OT/Layout/GSUB/SingleSubstFormat1.hh b/gfx/harfbuzz/src/OT/Layout/GSUB/SingleSubstFormat1.hh new file mode 100644 index 0000000000..850be86c04 --- /dev/null +++ b/gfx/harfbuzz/src/OT/Layout/GSUB/SingleSubstFormat1.hh @@ -0,0 +1,204 @@ +#ifndef OT_LAYOUT_GSUB_SINGLESUBSTFORMAT1_HH +#define OT_LAYOUT_GSUB_SINGLESUBSTFORMAT1_HH + +#include "Common.hh" + +namespace OT { +namespace Layout { +namespace GSUB_impl { + +template <typename Types> +struct SingleSubstFormat1_3 +{ + protected: + HBUINT16 format; /* Format identifier--format = 1 */ + typename Types::template OffsetTo<Coverage> + coverage; /* Offset to Coverage table--from + * beginning of Substitution table */ + typename Types::HBUINT + deltaGlyphID; /* Add to original GlyphID to get + * substitute GlyphID, modulo 0x10000 */ + + public: + DEFINE_SIZE_STATIC (2 + 2 * Types::size); + + bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (c->check_struct (this) && + coverage.sanitize (c, this) && + /* The coverage table may use a range to represent a set + * of glyphs, which means a small number of bytes can + * generate a large glyph set. Manually modify the + * sanitizer max ops to take this into account. + * + * Note: This check *must* be right after coverage sanitize. */ + c->check_ops ((this + coverage).get_population () >> 1)); + } + + hb_codepoint_t get_mask () const + { return (1 << (8 * Types::size)) - 1; } + + bool intersects (const hb_set_t *glyphs) const + { return (this+coverage).intersects (glyphs); } + + bool may_have_non_1to1 () const + { return false; } + + void closure (hb_closure_context_t *c) const + { + hb_codepoint_t d = deltaGlyphID; + hb_codepoint_t mask = get_mask (); + + /* Help fuzzer avoid this function as much. */ + unsigned pop = (this+coverage).get_population (); + if (pop >= mask) + return; + + hb_set_t intersection; + (this+coverage).intersect_set (c->parent_active_glyphs (), intersection); + + /* In degenerate fuzzer-found fonts, but not real fonts, + * this table can keep adding new glyphs in each round of closure. + * Refuse to close-over, if it maps glyph range to overlapping range. */ + hb_codepoint_t min_before = intersection.get_min (); + hb_codepoint_t max_before = intersection.get_max (); + hb_codepoint_t min_after = (min_before + d) & mask; + hb_codepoint_t max_after = (max_before + d) & mask; + if (intersection.get_population () == max_before - min_before + 1 && + ((min_before <= min_after && min_after <= max_before) || + (min_before <= max_after && max_after <= max_before))) + return; + + + hb_iter (intersection) + | hb_map ([d, mask] (hb_codepoint_t g) { return (g + d) & mask; }) + | hb_sink (c->output) + ; + } + + 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_codepoint_t d = deltaGlyphID; + hb_codepoint_t mask = get_mask (); + + + hb_iter (this+coverage) + | hb_map ([d, mask] (hb_codepoint_t g) { return (g + d) & mask; }) + | hb_sink (c->output) + ; + } + + const Coverage &get_coverage () const { return this+coverage; } + + bool would_apply (hb_would_apply_context_t *c) const + { return c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED; } + + unsigned + get_glyph_alternates (hb_codepoint_t glyph_id, + unsigned start_offset, + unsigned *alternate_count /* IN/OUT. May be NULL. */, + hb_codepoint_t *alternate_glyphs /* OUT. May be NULL. */) const + { + unsigned int index = (this+coverage).get_coverage (glyph_id); + if (likely (index == NOT_COVERED)) + { + if (alternate_count) + *alternate_count = 0; + return 0; + } + + if (alternate_count && *alternate_count) + { + hb_codepoint_t d = deltaGlyphID; + hb_codepoint_t mask = get_mask (); + + glyph_id = (glyph_id + d) & mask; + + *alternate_glyphs = glyph_id; + *alternate_count = 1; + } + + return 1; + } + + bool apply (hb_ot_apply_context_t *c) const + { + TRACE_APPLY (this); + hb_codepoint_t glyph_id = c->buffer->cur().codepoint; + unsigned int index = (this+coverage).get_coverage (glyph_id); + if (likely (index == NOT_COVERED)) return_trace (false); + + hb_codepoint_t d = deltaGlyphID; + hb_codepoint_t mask = get_mask (); + + glyph_id = (glyph_id + d) & mask; + + if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ()) + { + c->buffer->sync_so_far (); + c->buffer->message (c->font, + "replacing glyph at %u (single substitution)", + c->buffer->idx); + } + + c->replace_glyph (glyph_id); + + if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ()) + { + c->buffer->message (c->font, + "replaced glyph at %u (single substitution)", + c->buffer->idx - 1u); + } + + return_trace (true); + } + + template<typename Iterator, + hb_requires (hb_is_sorted_source_of (Iterator, hb_codepoint_t))> + bool serialize (hb_serialize_context_t *c, + Iterator glyphs, + unsigned delta) + { + TRACE_SERIALIZE (this); + if (unlikely (!c->extend_min (this))) return_trace (false); + if (unlikely (!coverage.serialize_serialize (c, glyphs))) return_trace (false); + c->check_assign (deltaGlyphID, delta, HB_SERIALIZE_ERROR_INT_OVERFLOW); + return_trace (true); + } + + 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; + + hb_codepoint_t d = deltaGlyphID; + hb_codepoint_t mask = get_mask (); + + hb_set_t intersection; + (this+coverage).intersect_set (glyphset, intersection); + + auto it = + + hb_iter (intersection) + | hb_map_retains_sorting ([d, mask] (hb_codepoint_t g) { + return hb_codepoint_pair_t (g, + (g + d) & mask); }) + | hb_filter (glyphset, hb_second) + | hb_map_retains_sorting ([&] (hb_codepoint_pair_t p) -> hb_codepoint_pair_t + { return hb_pair (glyph_map[p.first], glyph_map[p.second]); }) + ; + + bool ret = bool (it); + SingleSubst_serialize (c->serializer, it); + return_trace (ret); + } +}; + +} +} +} + + +#endif /* OT_LAYOUT_GSUB_SINGLESUBSTFORMAT1_HH */ |