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/*
* Copyright © 2007,2008,2009 Red Hat, Inc.
* Copyright © 2010,2012 Google, Inc.
*
* This is part of HarfBuzz, a text shaping 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
* Google Author(s): Behdad Esfahbod, Garret Rieger
*/
#ifndef OT_LAYOUT_COMMON_COVERAGEFORMAT2_HH
#define OT_LAYOUT_COMMON_COVERAGEFORMAT2_HH
#include "RangeRecord.hh"
namespace OT {
namespace Layout {
namespace Common {
template <typename Types>
struct CoverageFormat2_4
{
friend struct Coverage;
protected:
HBUINT16 coverageFormat; /* Format identifier--format = 2 */
SortedArray16Of<RangeRecord<Types>>
rangeRecord; /* Array of glyph ranges--ordered by
* Start GlyphID. rangeCount entries
* long */
public:
DEFINE_SIZE_ARRAY (4, rangeRecord);
private:
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (rangeRecord.sanitize (c));
}
unsigned int get_coverage (hb_codepoint_t glyph_id) const
{
const RangeRecord<Types> &range = rangeRecord.bsearch (glyph_id);
return likely (range.first <= range.last)
? (unsigned int) range.value + (glyph_id - range.first)
: NOT_COVERED;
}
unsigned get_population () const
{
typename Types::large_int ret = 0;
for (const auto &r : rangeRecord)
ret += r.get_population ();
return ret > UINT_MAX ? UINT_MAX : (unsigned) ret;
}
template <typename Iterator,
hb_requires (hb_is_sorted_source_of (Iterator, hb_codepoint_t))>
bool serialize (hb_serialize_context_t *c, Iterator glyphs)
{
TRACE_SERIALIZE (this);
if (unlikely (!c->extend_min (this))) return_trace (false);
unsigned num_ranges = 0;
hb_codepoint_t last = (hb_codepoint_t) -2;
for (auto g: glyphs)
{
if (last + 1 != g)
num_ranges++;
last = g;
}
if (unlikely (!rangeRecord.serialize (c, num_ranges))) return_trace (false);
if (!num_ranges) return_trace (true);
unsigned count = 0;
unsigned range = (unsigned) -1;
last = (hb_codepoint_t) -2;
unsigned unsorted = false;
for (auto g: glyphs)
{
if (last + 1 != g)
{
if (unlikely (last != (hb_codepoint_t) -2 && last + 1 > g))
unsorted = true;
range++;
rangeRecord.arrayZ[range].first = g;
rangeRecord.arrayZ[range].value = count;
}
rangeRecord.arrayZ[range].last = g;
last = g;
count++;
}
if (unlikely (unsorted))
rangeRecord.as_array ().qsort (RangeRecord<Types>::cmp_range);
return_trace (true);
}
bool intersects (const hb_set_t *glyphs) const
{
if (rangeRecord.len > glyphs->get_population () * hb_bit_storage ((unsigned) rangeRecord.len) / 2)
{
for (auto g : *glyphs)
if (get_coverage (g) != NOT_COVERED)
return true;
return false;
}
return hb_any (+ hb_iter (rangeRecord)
| hb_map ([glyphs] (const RangeRecord<Types> &range) { return range.intersects (*glyphs); }));
}
bool intersects_coverage (const hb_set_t *glyphs, unsigned int index) const
{
auto *range = rangeRecord.as_array ().bsearch (index);
if (range)
return range->intersects (*glyphs);
return false;
}
template <typename IterableOut,
hb_requires (hb_is_sink_of (IterableOut, hb_codepoint_t))>
void intersect_set (const hb_set_t &glyphs, IterableOut&& intersect_glyphs) const
{
/* Break out of loop for overlapping, broken, tables,
* to avoid fuzzer timouts. */
hb_codepoint_t last = 0;
for (const auto& range : rangeRecord)
{
if (unlikely (range.first < last))
break;
last = range.last;
for (hb_codepoint_t g = range.first - 1;
glyphs.next (&g) && g <= last;)
intersect_glyphs << g;
}
}
template <typename set_t>
bool collect_coverage (set_t *glyphs) const
{
for (const auto& range: rangeRecord)
if (unlikely (!range.collect_coverage (glyphs)))
return false;
return true;
}
public:
/* Older compilers need this to be public. */
struct iter_t
{
void init (const CoverageFormat2_4 &c_)
{
c = &c_;
coverage = 0;
i = 0;
j = c->rangeRecord.len ? c->rangeRecord[0].first : 0;
if (unlikely (c->rangeRecord[0].first > c->rangeRecord[0].last))
{
/* Broken table. Skip. */
i = c->rangeRecord.len;
j = 0;
}
}
bool __more__ () const { return i < c->rangeRecord.len; }
void __next__ ()
{
if (j >= c->rangeRecord[i].last)
{
i++;
if (__more__ ())
{
unsigned int old = coverage;
j = c->rangeRecord.arrayZ[i].first;
coverage = c->rangeRecord.arrayZ[i].value;
if (unlikely (coverage != old + 1))
{
/* Broken table. Skip. Important to avoid DoS.
* Also, our callers depend on coverage being
* consecutive and monotonically increasing,
* ie. iota(). */
i = c->rangeRecord.len;
j = 0;
return;
}
}
else
j = 0;
return;
}
coverage++;
j++;
}
hb_codepoint_t get_glyph () const { return j; }
bool operator != (const iter_t& o) const
{ return i != o.i || j != o.j; }
iter_t __end__ () const
{
iter_t it;
it.init (*c);
it.i = c->rangeRecord.len;
it.j = 0;
return it;
}
private:
const struct CoverageFormat2_4 *c;
unsigned int i, coverage;
hb_codepoint_t j;
};
private:
};
}
}
}
#endif // #ifndef OT_LAYOUT_COMMON_COVERAGEFORMAT2_HH