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#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 */
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