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+/*
+ * Copyright © 2012,2017 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.
+ *
+ * Google Author(s): Behdad Esfahbod
+ */
+
+#ifndef HB_SET_HH
+#define HB_SET_HH
+
+#include "hb.hh"
+#include "hb-machinery.hh"
+
+
+/*
+ * hb_set_t
+ */
+
+/* TODO Keep a free-list so we can free pages that are completely zeroed. At that
+ * point maybe also use a sentinel value for "all-1" pages? */
+
+struct hb_set_t
+{
+ HB_DELETE_COPY_ASSIGN (hb_set_t);
+ hb_set_t () { init (); }
+ ~hb_set_t () { fini (); }
+
+ struct page_map_t
+ {
+ int cmp (const page_map_t &o) const { return (int) o.major - (int) major; }
+
+ uint32_t major;
+ uint32_t index;
+ };
+
+ struct page_t
+ {
+ void init0 () { v.clear (); }
+ void init1 () { v.clear (0xFF); }
+
+ unsigned int len () const
+ { return ARRAY_LENGTH_CONST (v); }
+
+ bool is_empty () const
+ {
+ for (unsigned int i = 0; i < len (); i++)
+ if (v[i])
+ return false;
+ return true;
+ }
+
+ void add (hb_codepoint_t g) { elt (g) |= mask (g); }
+ void del (hb_codepoint_t g) { elt (g) &= ~mask (g); }
+ bool get (hb_codepoint_t g) const { return elt (g) & mask (g); }
+
+ void add_range (hb_codepoint_t a, hb_codepoint_t b)
+ {
+ elt_t *la = &elt (a);
+ elt_t *lb = &elt (b);
+ if (la == lb)
+ *la |= (mask (b) << 1) - mask(a);
+ else
+ {
+ *la |= ~(mask (a) - 1);
+ la++;
+
+ memset (la, 0xff, (char *) lb - (char *) la);
+
+ *lb |= ((mask (b) << 1) - 1);
+ }
+ }
+
+ void del_range (hb_codepoint_t a, hb_codepoint_t b)
+ {
+ elt_t *la = &elt (a);
+ elt_t *lb = &elt (b);
+ if (la == lb)
+ *la &= ~((mask (b) << 1) - mask(a));
+ else
+ {
+ *la &= mask (a) - 1;
+ la++;
+
+ memset (la, 0, (char *) lb - (char *) la);
+
+ *lb &= ~((mask (b) << 1) - 1);
+ }
+ }
+
+ bool is_equal (const page_t *other) const
+ {
+ return 0 == hb_memcmp (&v, &other->v, sizeof (v));
+ }
+
+ unsigned int get_population () const
+ {
+ unsigned int pop = 0;
+ for (unsigned int i = 0; i < len (); i++)
+ pop += hb_popcount (v[i]);
+ return pop;
+ }
+
+ bool next (hb_codepoint_t *codepoint) const
+ {
+ unsigned int m = (*codepoint + 1) & MASK;
+ if (!m)
+ {
+ *codepoint = INVALID;
+ return false;
+ }
+ unsigned int i = m / ELT_BITS;
+ unsigned int j = m & ELT_MASK;
+
+ const elt_t vv = v[i] & ~((elt_t (1) << j) - 1);
+ for (const elt_t *p = &vv; i < len (); p = &v[++i])
+ if (*p)
+ {
+ *codepoint = i * ELT_BITS + elt_get_min (*p);
+ return true;
+ }
+
+ *codepoint = INVALID;
+ return false;
+ }
+ bool previous (hb_codepoint_t *codepoint) const
+ {
+ unsigned int m = (*codepoint - 1) & MASK;
+ if (m == MASK)
+ {
+ *codepoint = INVALID;
+ return false;
+ }
+ unsigned int i = m / ELT_BITS;
+ unsigned int j = m & ELT_MASK;
+
+ /* Fancy mask to avoid shifting by elt_t bitsize, which is undefined. */
+ const elt_t mask = j < 8 * sizeof (elt_t) - 1 ?
+ ((elt_t (1) << (j + 1)) - 1) :
+ (elt_t) -1;
+ const elt_t vv = v[i] & mask;
+ const elt_t *p = &vv;
+ while (true)
+ {
+ if (*p)
+ {
+ *codepoint = i * ELT_BITS + elt_get_max (*p);
+ return true;
+ }
+ if ((int) i <= 0) break;
+ p = &v[--i];
+ }
+
+ *codepoint = INVALID;
+ return false;
+ }
+ hb_codepoint_t get_min () const
+ {
+ for (unsigned int i = 0; i < len (); i++)
+ if (v[i])
+ return i * ELT_BITS + elt_get_min (v[i]);
+ return INVALID;
+ }
+ hb_codepoint_t get_max () const
+ {
+ for (int i = len () - 1; i >= 0; i--)
+ if (v[i])
+ return i * ELT_BITS + elt_get_max (v[i]);
+ return 0;
+ }
+
+ typedef unsigned long long elt_t;
+ static constexpr unsigned PAGE_BITS = 512;
+ static_assert ((PAGE_BITS & ((PAGE_BITS) - 1)) == 0, "");
+
+ static unsigned int elt_get_min (const elt_t &elt) { return hb_ctz (elt); }
+ static unsigned int elt_get_max (const elt_t &elt) { return hb_bit_storage (elt) - 1; }
+
+ typedef hb_vector_size_t<elt_t, PAGE_BITS / 8> vector_t;
+
+ static constexpr unsigned ELT_BITS = sizeof (elt_t) * 8;
+ static constexpr unsigned ELT_MASK = ELT_BITS - 1;
+ static constexpr unsigned BITS = sizeof (vector_t) * 8;
+ static constexpr unsigned MASK = BITS - 1;
+ static_assert ((unsigned) PAGE_BITS == (unsigned) BITS, "");
+
+ elt_t &elt (hb_codepoint_t g) { return v[(g & MASK) / ELT_BITS]; }
+ elt_t const &elt (hb_codepoint_t g) const { return v[(g & MASK) / ELT_BITS]; }
+ elt_t mask (hb_codepoint_t g) const { return elt_t (1) << (g & ELT_MASK); }
+
+ vector_t v;
+ };
+ static_assert (page_t::PAGE_BITS == sizeof (page_t) * 8, "");
+
+ hb_object_header_t header;
+ bool successful; /* Allocations successful */
+ mutable unsigned int population;
+ hb_sorted_vector_t<page_map_t> page_map;
+ hb_vector_t<page_t> pages;
+
+ void init_shallow ()
+ {
+ successful = true;
+ population = 0;
+ page_map.init ();
+ pages.init ();
+ }
+ void init ()
+ {
+ hb_object_init (this);
+ init_shallow ();
+ }
+ void fini_shallow ()
+ {
+ population = 0;
+ page_map.fini ();
+ pages.fini ();
+ }
+ void fini ()
+ {
+ hb_object_fini (this);
+ fini_shallow ();
+ }
+
+ bool in_error () const { return !successful; }
+
+ bool resize (unsigned int count)
+ {
+ if (unlikely (!successful)) return false;
+ if (!pages.resize (count) || !page_map.resize (count))
+ {
+ pages.resize (page_map.length);
+ successful = false;
+ return false;
+ }
+ return true;
+ }
+
+ void reset ()
+ {
+ if (unlikely (hb_object_is_immutable (this)))
+ return;
+ clear ();
+ successful = true;
+ }
+
+ void clear ()
+ {
+ if (unlikely (hb_object_is_immutable (this)))
+ return;
+ population = 0;
+ page_map.resize (0);
+ pages.resize (0);
+ }
+ bool is_empty () const
+ {
+ unsigned int count = pages.length;
+ for (unsigned int i = 0; i < count; i++)
+ if (!pages[i].is_empty ())
+ return false;
+ return true;
+ }
+
+ void dirty () { population = UINT_MAX; }
+
+ void add (hb_codepoint_t g)
+ {
+ if (unlikely (!successful)) return;
+ if (unlikely (g == INVALID)) return;
+ dirty ();
+ page_t *page = page_for_insert (g); if (unlikely (!page)) return;
+ page->add (g);
+ }
+ bool add_range (hb_codepoint_t a, hb_codepoint_t b)
+ {
+ if (unlikely (!successful)) return true; /* https://github.com/harfbuzz/harfbuzz/issues/657 */
+ if (unlikely (a > b || a == INVALID || b == INVALID)) return false;
+ dirty ();
+ unsigned int ma = get_major (a);
+ unsigned int mb = get_major (b);
+ if (ma == mb)
+ {
+ page_t *page = page_for_insert (a); if (unlikely (!page)) return false;
+ page->add_range (a, b);
+ }
+ else
+ {
+ page_t *page = page_for_insert (a); if (unlikely (!page)) return false;
+ page->add_range (a, major_start (ma + 1) - 1);
+
+ for (unsigned int m = ma + 1; m < mb; m++)
+ {
+ page = page_for_insert (major_start (m)); if (unlikely (!page)) return false;
+ page->init1 ();
+ }
+
+ page = page_for_insert (b); if (unlikely (!page)) return false;
+ page->add_range (major_start (mb), b);
+ }
+ return true;
+ }
+
+ template <typename T>
+ void add_array (const T *array, unsigned int count, unsigned int stride=sizeof(T))
+ {
+ if (unlikely (!successful)) return;
+ if (!count) return;
+ dirty ();
+ hb_codepoint_t g = *array;
+ while (count)
+ {
+ unsigned int m = get_major (g);
+ page_t *page = page_for_insert (g); if (unlikely (!page)) return;
+ unsigned int start = major_start (m);
+ unsigned int end = major_start (m + 1);
+ do
+ {
+ page->add (g);
+
+ array = &StructAtOffsetUnaligned<T> (array, stride);
+ count--;
+ }
+ while (count && (g = *array, start <= g && g < end));
+ }
+ }
+
+ /* Might return false if array looks unsorted.
+ * Used for faster rejection of corrupt data. */
+ template <typename T>
+ bool add_sorted_array (const T *array, unsigned int count, unsigned int stride=sizeof(T))
+ {
+ if (unlikely (!successful)) return true; /* https://github.com/harfbuzz/harfbuzz/issues/657 */
+ if (!count) return true;
+ dirty ();
+ hb_codepoint_t g = *array;
+ hb_codepoint_t last_g = g;
+ while (count)
+ {
+ unsigned int m = get_major (g);
+ page_t *page = page_for_insert (g); if (unlikely (!page)) return false;
+ unsigned int end = major_start (m + 1);
+ do
+ {
+ /* If we try harder we can change the following comparison to <=;
+ * Not sure if it's worth it. */
+ if (g < last_g) return false;
+ last_g = g;
+ page->add (g);
+
+ array = (const T *) ((const char *) array + stride);
+ count--;
+ }
+ while (count && (g = *array, g < end));
+ }
+ return true;
+ }
+
+ void del (hb_codepoint_t g)
+ {
+ /* TODO perform op even if !successful. */
+ if (unlikely (!successful)) return;
+ page_t *page = page_for (g);
+ if (!page)
+ return;
+ dirty ();
+ page->del (g);
+ }
+
+ private:
+ void del_pages (int ds, int de)
+ {
+ if (ds <= de)
+ {
+ unsigned int write_index = 0;
+ for (unsigned int i = 0; i < page_map.length; i++)
+ {
+ int m = (int) page_map[i].major;
+ if (m < ds || de < m)
+ page_map[write_index++] = page_map[i];
+ }
+ compact (write_index);
+ resize (write_index);
+ }
+ }
+
+ public:
+ void del_range (hb_codepoint_t a, hb_codepoint_t b)
+ {
+ /* TODO perform op even if !successful. */
+ if (unlikely (!successful)) return;
+ if (unlikely (a > b || a == INVALID || b == INVALID)) return;
+ dirty ();
+ unsigned int ma = get_major (a);
+ unsigned int mb = get_major (b);
+ /* Delete pages from ds through de if ds <= de. */
+ int ds = (a == major_start (ma))? (int) ma: (int) (ma + 1);
+ int de = (b + 1 == major_start (mb + 1))? (int) mb: ((int) mb - 1);
+ if (ds > de || (int) ma < ds)
+ {
+ page_t *page = page_for (a);
+ if (page)
+ {
+ if (ma == mb)
+ page->del_range (a, b);
+ else
+ page->del_range (a, major_start (ma + 1) - 1);
+ }
+ }
+ if (de < (int) mb && ma != mb)
+ {
+ page_t *page = page_for (b);
+ if (page)
+ page->del_range (major_start (mb), b);
+ }
+ del_pages (ds, de);
+ }
+
+ bool get (hb_codepoint_t g) const
+ {
+ const page_t *page = page_for (g);
+ if (!page)
+ return false;
+ return page->get (g);
+ }
+
+ /* Has interface. */
+ static constexpr bool SENTINEL = false;
+ typedef bool value_t;
+ value_t operator [] (hb_codepoint_t k) const { return get (k); }
+ bool has (hb_codepoint_t k) const { return (*this)[k] != SENTINEL; }
+ /* Predicate. */
+ bool operator () (hb_codepoint_t k) const { return has (k); }
+
+ /* Sink interface. */
+ hb_set_t& operator << (hb_codepoint_t v)
+ { add (v); return *this; }
+ hb_set_t& operator << (const hb_pair_t<hb_codepoint_t, hb_codepoint_t>& range)
+ { add_range (range.first, range.second); return *this; }
+
+ bool intersects (hb_codepoint_t first, hb_codepoint_t last) const
+ {
+ hb_codepoint_t c = first - 1;
+ return next (&c) && c <= last;
+ }
+ void set (const hb_set_t *other)
+ {
+ if (unlikely (!successful)) return;
+ unsigned int count = other->pages.length;
+ if (!resize (count))
+ return;
+ population = other->population;
+ memcpy ((void *) pages, (const void *) other->pages, count * pages.item_size);
+ memcpy ((void *) page_map, (const void *) other->page_map, count * page_map.item_size);
+ }
+
+ bool is_equal (const hb_set_t *other) const
+ {
+ if (get_population () != other->get_population ())
+ return false;
+
+ unsigned int na = pages.length;
+ unsigned int nb = other->pages.length;
+
+ unsigned int a = 0, b = 0;
+ for (; a < na && b < nb; )
+ {
+ if (page_at (a).is_empty ()) { a++; continue; }
+ if (other->page_at (b).is_empty ()) { b++; continue; }
+ if (page_map[a].major != other->page_map[b].major ||
+ !page_at (a).is_equal (&other->page_at (b)))
+ return false;
+ a++;
+ b++;
+ }
+ for (; a < na; a++)
+ if (!page_at (a).is_empty ()) { return false; }
+ for (; b < nb; b++)
+ if (!other->page_at (b).is_empty ()) { return false; }
+
+ return true;
+ }
+
+ bool is_subset (const hb_set_t *larger_set) const
+ {
+ if (get_population () > larger_set->get_population ())
+ return false;
+
+ /* TODO Optimize to use pages. */
+ hb_codepoint_t c = INVALID;
+ while (next (&c))
+ if (!larger_set->has (c))
+ return false;
+
+ return true;
+ }
+
+ void compact (unsigned int length)
+ {
+ hb_vector_t<uint32_t> old_index_to_page_map_index;
+ old_index_to_page_map_index.resize(pages.length);
+ for (uint32_t i = 0; i < old_index_to_page_map_index.length; i++)
+ old_index_to_page_map_index[i] = 0xFFFFFFFF;
+
+ for (uint32_t i = 0; i < length; i++)
+ old_index_to_page_map_index[page_map[i].index] = i;
+
+ compact_pages (old_index_to_page_map_index);
+ }
+
+ void compact_pages (const hb_vector_t<uint32_t>& old_index_to_page_map_index)
+ {
+ unsigned int write_index = 0;
+ for (unsigned int i = 0; i < pages.length; i++)
+ {
+ if (old_index_to_page_map_index[i] == 0xFFFFFFFF) continue;
+
+ if (write_index < i)
+ pages[write_index] = pages[i];
+
+ page_map[old_index_to_page_map_index[i]].index = write_index;
+ write_index++;
+ }
+ }
+
+ template <typename Op>
+ void process (const Op& op, const hb_set_t *other)
+ {
+ if (unlikely (!successful)) return;
+
+ dirty ();
+
+ unsigned int na = pages.length;
+ unsigned int nb = other->pages.length;
+ unsigned int next_page = na;
+
+ unsigned int count = 0, newCount = 0;
+ unsigned int a = 0, b = 0;
+ unsigned int write_index = 0;
+ for (; a < na && b < nb; )
+ {
+ if (page_map[a].major == other->page_map[b].major)
+ {
+ if (!Op::passthru_left)
+ {
+ // Move page_map entries that we're keeping from the left side set
+ // to the front of the page_map vector. This isn't necessary if
+ // passthru_left is set since no left side pages will be removed
+ // in that case.
+ if (write_index < a)
+ page_map[write_index] = page_map[a];
+ write_index++;
+ }
+
+ count++;
+ a++;
+ b++;
+ }
+ else if (page_map[a].major < other->page_map[b].major)
+ {
+ if (Op::passthru_left)
+ count++;
+ a++;
+ }
+ else
+ {
+ if (Op::passthru_right)
+ count++;
+ b++;
+ }
+ }
+ if (Op::passthru_left)
+ count += na - a;
+ if (Op::passthru_right)
+ count += nb - b;
+
+ if (!Op::passthru_left)
+ {
+ na = write_index;
+ next_page = write_index;
+ compact (write_index);
+ }
+
+ if (!resize (count))
+ return;
+
+ newCount = count;
+
+ /* Process in-place backward. */
+ a = na;
+ b = nb;
+ for (; a && b; )
+ {
+ if (page_map[a - 1].major == other->page_map[b - 1].major)
+ {
+ a--;
+ b--;
+ count--;
+ page_map[count] = page_map[a];
+ page_at (count).v = op (page_at (a).v, other->page_at (b).v);
+ }
+ else if (page_map[a - 1].major > other->page_map[b - 1].major)
+ {
+ a--;
+ if (Op::passthru_left)
+ {
+ count--;
+ page_map[count] = page_map[a];
+ }
+ }
+ else
+ {
+ b--;
+ if (Op::passthru_right)
+ {
+ count--;
+ page_map[count].major = other->page_map[b].major;
+ page_map[count].index = next_page++;
+ page_at (count).v = other->page_at (b).v;
+ }
+ }
+ }
+ if (Op::passthru_left)
+ while (a)
+ {
+ a--;
+ count--;
+ page_map[count] = page_map [a];
+ }
+ if (Op::passthru_right)
+ while (b)
+ {
+ b--;
+ count--;
+ page_map[count].major = other->page_map[b].major;
+ page_map[count].index = next_page++;
+ page_at (count).v = other->page_at (b).v;
+ }
+ assert (!count);
+ if (pages.length > newCount)
+ resize (newCount);
+ }
+
+ void union_ (const hb_set_t *other)
+ {
+ process (hb_bitwise_or, other);
+ }
+ void intersect (const hb_set_t *other)
+ {
+ process (hb_bitwise_and, other);
+ }
+ void subtract (const hb_set_t *other)
+ {
+ process (hb_bitwise_sub, other);
+ }
+ void symmetric_difference (const hb_set_t *other)
+ {
+ process (hb_bitwise_xor, other);
+ }
+ bool next (hb_codepoint_t *codepoint) const
+ {
+ if (unlikely (*codepoint == INVALID)) {
+ *codepoint = get_min ();
+ return *codepoint != INVALID;
+ }
+
+ page_map_t map = {get_major (*codepoint), 0};
+ unsigned int i;
+ page_map.bfind (map, &i, HB_BFIND_NOT_FOUND_STORE_CLOSEST);
+ if (i < page_map.length && page_map[i].major == map.major)
+ {
+ if (pages[page_map[i].index].next (codepoint))
+ {
+ *codepoint += page_map[i].major * page_t::PAGE_BITS;
+ return true;
+ }
+ i++;
+ }
+ for (; i < page_map.length; i++)
+ {
+ hb_codepoint_t m = pages[page_map[i].index].get_min ();
+ if (m != INVALID)
+ {
+ *codepoint = page_map[i].major * page_t::PAGE_BITS + m;
+ return true;
+ }
+ }
+ *codepoint = INVALID;
+ return false;
+ }
+ bool previous (hb_codepoint_t *codepoint) const
+ {
+ if (unlikely (*codepoint == INVALID)) {
+ *codepoint = get_max ();
+ return *codepoint != INVALID;
+ }
+
+ page_map_t map = {get_major (*codepoint), 0};
+ unsigned int i;
+ page_map.bfind (map, &i, HB_BFIND_NOT_FOUND_STORE_CLOSEST);
+ if (i < page_map.length && page_map[i].major == map.major)
+ {
+ if (pages[page_map[i].index].previous (codepoint))
+ {
+ *codepoint += page_map[i].major * page_t::PAGE_BITS;
+ return true;
+ }
+ }
+ i--;
+ for (; (int) i >= 0; i--)
+ {
+ hb_codepoint_t m = pages[page_map[i].index].get_max ();
+ if (m != INVALID)
+ {
+ *codepoint = page_map[i].major * page_t::PAGE_BITS + m;
+ return true;
+ }
+ }
+ *codepoint = INVALID;
+ return false;
+ }
+ bool next_range (hb_codepoint_t *first, hb_codepoint_t *last) const
+ {
+ hb_codepoint_t i;
+
+ i = *last;
+ if (!next (&i))
+ {
+ *last = *first = INVALID;
+ return false;
+ }
+
+ /* TODO Speed up. */
+ *last = *first = i;
+ while (next (&i) && i == *last + 1)
+ (*last)++;
+
+ return true;
+ }
+ bool previous_range (hb_codepoint_t *first, hb_codepoint_t *last) const
+ {
+ hb_codepoint_t i;
+
+ i = *first;
+ if (!previous (&i))
+ {
+ *last = *first = INVALID;
+ return false;
+ }
+
+ /* TODO Speed up. */
+ *last = *first = i;
+ while (previous (&i) && i == *first - 1)
+ (*first)--;
+
+ return true;
+ }
+
+ unsigned int get_population () const
+ {
+ if (population != UINT_MAX)
+ return population;
+
+ unsigned int pop = 0;
+ unsigned int count = pages.length;
+ for (unsigned int i = 0; i < count; i++)
+ pop += pages[i].get_population ();
+
+ population = pop;
+ return pop;
+ }
+ hb_codepoint_t get_min () const
+ {
+ unsigned int count = pages.length;
+ for (unsigned int i = 0; i < count; i++)
+ if (!page_at (i).is_empty ())
+ return page_map[i].major * page_t::PAGE_BITS + page_at (i).get_min ();
+ return INVALID;
+ }
+ hb_codepoint_t get_max () const
+ {
+ unsigned int count = pages.length;
+ for (int i = count - 1; i >= 0; i++)
+ if (!page_at (i).is_empty ())
+ return page_map[(unsigned) i].major * page_t::PAGE_BITS + page_at (i).get_max ();
+ return INVALID;
+ }
+
+ static constexpr hb_codepoint_t INVALID = HB_SET_VALUE_INVALID;
+
+ /*
+ * Iterator implementation.
+ */
+ struct iter_t : hb_iter_with_fallback_t<iter_t, hb_codepoint_t>
+ {
+ static constexpr bool is_sorted_iterator = true;
+ iter_t (const hb_set_t &s_ = Null (hb_set_t),
+ bool init = true) : s (&s_), v (INVALID), l(0)
+ {
+ if (init)
+ {
+ l = s->get_population () + 1;
+ __next__ ();
+ }
+ }
+
+ typedef hb_codepoint_t __item_t__;
+ hb_codepoint_t __item__ () const { return v; }
+ bool __more__ () const { return v != INVALID; }
+ void __next__ () { s->next (&v); if (l) l--; }
+ void __prev__ () { s->previous (&v); }
+ unsigned __len__ () const { return l; }
+ iter_t end () const { return iter_t (*s, false); }
+ bool operator != (const iter_t& o) const
+ { return s != o.s || v != o.v; }
+
+ protected:
+ const hb_set_t *s;
+ hb_codepoint_t v;
+ unsigned l;
+ };
+ iter_t iter () const { return iter_t (*this); }
+ operator iter_t () const { return iter (); }
+
+ protected:
+
+ page_t *page_for_insert (hb_codepoint_t g)
+ {
+ page_map_t map = {get_major (g), pages.length};
+ unsigned int i;
+ if (!page_map.bfind (map, &i, HB_BFIND_NOT_FOUND_STORE_CLOSEST))
+ {
+ if (!resize (pages.length + 1))
+ return nullptr;
+
+ pages[map.index].init0 ();
+ memmove (page_map + i + 1,
+ page_map + i,
+ (page_map.length - 1 - i) * page_map.item_size);
+ page_map[i] = map;
+ }
+ return &pages[page_map[i].index];
+ }
+ page_t *page_for (hb_codepoint_t g)
+ {
+ page_map_t key = {get_major (g)};
+ const page_map_t *found = page_map.bsearch (key);
+ if (found)
+ return &pages[found->index];
+ return nullptr;
+ }
+ const page_t *page_for (hb_codepoint_t g) const
+ {
+ page_map_t key = {get_major (g)};
+ const page_map_t *found = page_map.bsearch (key);
+ if (found)
+ return &pages[found->index];
+ return nullptr;
+ }
+ page_t &page_at (unsigned int i) { return pages[page_map[i].index]; }
+ const page_t &page_at (unsigned int i) const { return pages[page_map[i].index]; }
+ unsigned int get_major (hb_codepoint_t g) const { return g / page_t::PAGE_BITS; }
+ hb_codepoint_t major_start (unsigned int major) const { return major * page_t::PAGE_BITS; }
+};
+
+
+#endif /* HB_SET_HH */