summaryrefslogtreecommitdiffstats
path: root/gfx/harfbuzz/src/hb-array.hh
blob: 1a22e15c0fb4a2a6408906f9d5fe938f7f05a05c (plain)
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
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
/*
 * Copyright © 2018  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_ARRAY_HH
#define HB_ARRAY_HH

#include "hb.hh"
#include "hb-algs.hh"
#include "hb-iter.hh"
#include "hb-null.hh"


template <typename Type>
struct hb_sorted_array_t;

enum hb_not_found_t
{
  HB_NOT_FOUND_DONT_STORE,
  HB_NOT_FOUND_STORE,
  HB_NOT_FOUND_STORE_CLOSEST,
};


template <typename Type>
struct hb_array_t : hb_iter_with_fallback_t<hb_array_t<Type>, Type&>
{
  /*
   * Constructors.
   */
  hb_array_t () = default;
  hb_array_t (const hb_array_t&) = default;
  ~hb_array_t () = default;
  hb_array_t& operator= (const hb_array_t&) = default;
  hb_array_t& operator= (hb_array_t&&) = default;

  constexpr hb_array_t (Type *array_, unsigned int length_) : arrayZ (array_), length (length_) {}
  template <unsigned int length_>
  constexpr hb_array_t (Type (&array_)[length_]) : hb_array_t (array_, length_) {}

  template <typename U,
	    hb_enable_if (hb_is_cr_convertible(U, Type))>
  constexpr hb_array_t (const hb_array_t<U> &o) :
    hb_iter_with_fallback_t<hb_array_t, Type&> (),
    arrayZ (o.arrayZ), length (o.length), backwards_length (o.backwards_length) {}
  template <typename U,
	    hb_enable_if (hb_is_cr_convertible(U, Type))>
  hb_array_t& operator = (const hb_array_t<U> &o)
  { arrayZ = o.arrayZ; length = o.length; backwards_length = o.backwards_length; return *this; }

  /*
   * Iterator implementation.
   */
  typedef Type& __item_t__;
  static constexpr bool is_random_access_iterator = true;
  Type& __item_at__ (unsigned i) const
  {
    if (unlikely (i >= length)) return CrapOrNull (Type);
    return arrayZ[i];
  }
  void __forward__ (unsigned n)
  {
    if (unlikely (n > length))
      n = length;
    length -= n;
    backwards_length += n;
    arrayZ += n;
  }
  void __rewind__ (unsigned n)
  {
    if (unlikely (n > backwards_length))
      n = backwards_length;
    length += n;
    backwards_length -= n;
    arrayZ -= n;
  }
  unsigned __len__ () const { return length; }
  /* Ouch. The operator== compares the contents of the array.  For range-based for loops,
   * it's best if we can just compare arrayZ, though comparing contents is still fast,
   * but also would require that Type has operator==.  As such, we optimize this operator
   * for range-based for loop and just compare arrayZ and length.
   *
   * The above comment is outdated now because we implemented separate begin/end to
   * objects that were using hb_array_t for range-based loop before. */
  bool operator != (const hb_array_t& o) const
  { return this->arrayZ != o.arrayZ || this->length != o.length; }

  /* Faster range-based for loop without bounds-check. */
  Type *begin () const { return arrayZ; }
  Type *end () const { return arrayZ + length; }


  /* Extra operators.
   */
  Type * operator & () const { return arrayZ; }
  operator hb_array_t<const Type> () { return hb_array_t<const Type> (arrayZ, length); }
  template <typename T> operator T * () const { return arrayZ; }

  HB_INTERNAL bool operator == (const hb_array_t &o) const;

  uint32_t hash () const
  {
    // FNV-1a hash function
    uint32_t current = /*cbf29ce4*/0x84222325;
    for (auto &v : *this)
    {
      current = current ^ hb_hash (v);
      current = current * 16777619;
    }
    return current;
  }

  /*
   * Compare, Sort, and Search.
   */

  /* Note: our compare is NOT lexicographic; it also does NOT call Type::cmp. */
  int cmp (const hb_array_t &a) const
  {
    if (length != a.length)
      return (int) a.length - (int) length;
    return hb_memcmp (a.arrayZ, arrayZ, get_size ());
  }
  HB_INTERNAL static int cmp (const void *pa, const void *pb)
  {
    hb_array_t *a = (hb_array_t *) pa;
    hb_array_t *b = (hb_array_t *) pb;
    return b->cmp (*a);
  }

  template <typename T>
  Type *lsearch (const T &x, Type *not_found = nullptr)
  {
    unsigned i;
    return lfind (x, &i) ? &this->arrayZ[i] : not_found;
  }
  template <typename T>
  const Type *lsearch (const T &x, const Type *not_found = nullptr) const
  {
    unsigned i;
    return lfind (x, &i) ? &this->arrayZ[i] : not_found;
  }
  template <typename T>
  bool lfind (const T &x, unsigned *pos = nullptr,
	      hb_not_found_t not_found = HB_NOT_FOUND_DONT_STORE,
	      unsigned int to_store = (unsigned int) -1) const
  {
    for (unsigned i = 0; i < length; ++i)
      if (hb_equal (x, this->arrayZ[i]))
      {
	if (pos)
	  *pos = i;
	return true;
      }

    if (pos)
    {
      switch (not_found)
      {
	case HB_NOT_FOUND_DONT_STORE:
	  break;

	case HB_NOT_FOUND_STORE:
	  *pos = to_store;
	  break;

	case HB_NOT_FOUND_STORE_CLOSEST:
	  *pos = length;
	  break;
      }
    }
    return false;
  }

  hb_sorted_array_t<Type> qsort (int (*cmp_)(const void*, const void*))
  {
    //static_assert (hb_enable_if (hb_is_trivially_copy_assignable(Type)), "");
    if (likely (length))
      hb_qsort (arrayZ, length, this->get_item_size (), cmp_);
    return hb_sorted_array_t<Type> (*this);
  }
  hb_sorted_array_t<Type> qsort ()
  {
    //static_assert (hb_enable_if (hb_is_trivially_copy_assignable(Type)), "");
    if (likely (length))
      hb_qsort (arrayZ, length, this->get_item_size (), Type::cmp);
    return hb_sorted_array_t<Type> (*this);
  }

  /*
   * Other methods.
   */

  unsigned int get_size () const { return length * this->get_item_size (); }

  /*
   * Reverse the order of items in this array in the range [start, end).
   */
  void reverse (unsigned start = 0, unsigned end = -1)
  {
    start = hb_min (start, length);
    end = hb_min (end, length);

    if (end < start + 2)
      return;

    for (unsigned lhs = start, rhs = end - 1; lhs < rhs; lhs++, rhs--)
      hb_swap (arrayZ[rhs], arrayZ[lhs]);
  }

  hb_array_t sub_array (unsigned int start_offset = 0, unsigned int *seg_count = nullptr /* IN/OUT */) const
  {
    if (!start_offset && !seg_count)
      return *this;

    unsigned int count = length;
    if (unlikely (start_offset > count))
      count = 0;
    else
      count -= start_offset;
    if (seg_count)
      count = *seg_count = hb_min (count, *seg_count);
    return hb_array_t (arrayZ + start_offset, count);
  }
  hb_array_t sub_array (unsigned int start_offset, unsigned int seg_count) const
  { return sub_array (start_offset, &seg_count); }

  hb_array_t truncate (unsigned length) const { return sub_array (0, length); }

  template <typename T,
	    unsigned P = sizeof (Type),
	    hb_enable_if (P == 1)>
  const T *as () const
  { return length < hb_min_size (T) ? &Null (T) : reinterpret_cast<const T *> (arrayZ); }

  template <typename T,
	    unsigned P = sizeof (Type),
	    hb_enable_if (P == 1)>
  bool check_range (const T *p, unsigned int size = T::static_size) const
  {
    return arrayZ <= ((const char *) p)
	&& ((const char *) p) <= arrayZ + length
	&& (unsigned int) (arrayZ + length - (const char *) p) >= size;
  }

  /* Only call if you allocated the underlying array using hb_malloc() or similar. */
  void fini ()
  { hb_free ((void *) arrayZ); arrayZ = nullptr; length = 0; }

  template <typename hb_serialize_context_t,
	    typename U = Type,
	    hb_enable_if (!(sizeof (U) < sizeof (long long) && hb_is_trivially_copy_assignable(hb_decay<Type>)))>
  hb_array_t copy (hb_serialize_context_t *c) const
  {
    TRACE_SERIALIZE (this);
    auto* out = c->start_embed (arrayZ);
    if (unlikely (!c->extend_size (out, get_size (), false))) return_trace (hb_array_t ());
    for (unsigned i = 0; i < length; i++)
      out[i] = arrayZ[i]; /* TODO: add version that calls c->copy() */
    return_trace (hb_array_t (out, length));
  }

  template <typename hb_serialize_context_t,
	    typename U = Type,
	    hb_enable_if (sizeof (U) < sizeof (long long) && hb_is_trivially_copy_assignable(hb_decay<Type>))>
  hb_array_t copy (hb_serialize_context_t *c) const
  {
    TRACE_SERIALIZE (this);
    auto* out = c->start_embed (arrayZ);
    if (unlikely (!c->extend_size (out, get_size (), false))) return_trace (hb_array_t ());
    hb_memcpy (out, arrayZ, get_size ());
    return_trace (hb_array_t (out, length));
  }

  template <typename hb_sanitize_context_t>
  bool sanitize (hb_sanitize_context_t *c) const
  { return c->check_array (arrayZ, length); }

  /*
   * Members
   */

  public:
  Type *arrayZ = nullptr;
  unsigned int length = 0;
  unsigned int backwards_length = 0;
};
template <typename T> inline hb_array_t<T>
hb_array ()
{ return hb_array_t<T> (); }
template <typename T> inline hb_array_t<T>
hb_array (T *array, unsigned int length)
{ return hb_array_t<T> (array, length); }
template <typename T, unsigned int length_> inline hb_array_t<T>
hb_array (T (&array_)[length_])
{ return hb_array_t<T> (array_); }

template <typename Type>
struct hb_sorted_array_t :
	hb_array_t<Type>,
	hb_iter_t<hb_sorted_array_t<Type>, Type&>
{
  typedef hb_iter_t<hb_sorted_array_t, Type&> iter_base_t;
  HB_ITER_USING (iter_base_t);
  static constexpr bool is_random_access_iterator = true;
  static constexpr bool is_sorted_iterator = true;

  hb_sorted_array_t () = default;
  hb_sorted_array_t (const hb_sorted_array_t&) = default;
  ~hb_sorted_array_t () = default;
  hb_sorted_array_t& operator= (const hb_sorted_array_t&) = default;
  hb_sorted_array_t& operator= (hb_sorted_array_t&&) = default;

  constexpr hb_sorted_array_t (Type *array_, unsigned int length_) : hb_array_t<Type> (array_, length_) {}
  template <unsigned int length_>
  constexpr hb_sorted_array_t (Type (&array_)[length_]) : hb_array_t<Type> (array_) {}

  template <typename U,
	    hb_enable_if (hb_is_cr_convertible(U, Type))>
  constexpr hb_sorted_array_t (const hb_array_t<U> &o) :
    hb_array_t<Type> (o),
    hb_iter_t<hb_sorted_array_t, Type&> () {}
  template <typename U,
	    hb_enable_if (hb_is_cr_convertible(U, Type))>
  hb_sorted_array_t& operator = (const hb_array_t<U> &o)
  { hb_array_t<Type> (*this) = o; return *this; }

  /* Iterator implementation. */

  /* See comment in hb_array_of::operator != */
  bool operator != (const hb_sorted_array_t& o) const
  { return this->arrayZ != o.arrayZ || this->length != o.length; }

  /* Faster range-based for loop without bounds-check. */
  Type *begin () const { return this->arrayZ; }
  Type *end () const { return this->arrayZ + this->length; }


  hb_sorted_array_t sub_array (unsigned int start_offset, unsigned int *seg_count /* IN/OUT */) const
  { return hb_sorted_array_t (((const hb_array_t<Type> *) (this))->sub_array (start_offset, seg_count)); }
  hb_sorted_array_t sub_array (unsigned int start_offset, unsigned int seg_count) const
  { return sub_array (start_offset, &seg_count); }

  hb_sorted_array_t truncate (unsigned length) const { return sub_array (0, length); }

  template <typename T>
  Type *bsearch (const T &x, Type *not_found = nullptr)
  {
    unsigned int i;
    return bfind (x, &i) ? &this->arrayZ[i] : not_found;
  }
  template <typename T>
  const Type *bsearch (const T &x, const Type *not_found = nullptr) const
  {
    unsigned int i;
    return bfind (x, &i) ? &this->arrayZ[i] : not_found;
  }
  template <typename T>
  bool bfind (const T &x, unsigned int *i = nullptr,
	      hb_not_found_t not_found = HB_NOT_FOUND_DONT_STORE,
	      unsigned int to_store = (unsigned int) -1) const
  {
    unsigned pos;

    if (bsearch_impl (x, &pos))
    {
      if (i)
	*i = pos;
      return true;
    }

    if (i)
    {
      switch (not_found)
      {
	case HB_NOT_FOUND_DONT_STORE:
	  break;

	case HB_NOT_FOUND_STORE:
	  *i = to_store;
	  break;

	case HB_NOT_FOUND_STORE_CLOSEST:
	  *i = pos;
	  break;
      }
    }
    return false;
  }
  template <typename T, typename ...Ts>
  bool bsearch_impl (const T &x, unsigned *pos, Ts... ds) const
  {
    return hb_bsearch_impl (pos,
			    x,
			    this->arrayZ,
			    this->length,
			    sizeof (Type),
			    _hb_cmp_method<T, Type, Ts...>,
			    std::forward<Ts> (ds)...);
  }
};
template <typename T> inline hb_sorted_array_t<T>
hb_sorted_array (T *array, unsigned int length)
{ return hb_sorted_array_t<T> (array, length); }
template <typename T, unsigned int length_> inline hb_sorted_array_t<T>
hb_sorted_array (T (&array_)[length_])
{ return hb_sorted_array_t<T> (array_); }

template <typename T>
inline bool hb_array_t<T>::operator == (const hb_array_t<T> &o) const
{
  if (o.length != this->length) return false;
  for (unsigned int i = 0; i < this->length; i++) {
    if (this->arrayZ[i] != o.arrayZ[i]) return false;
  }
  return true;
}
template <>
inline bool hb_array_t<const char>::operator == (const hb_array_t<const char> &o) const
{
  if (o.length != this->length) return false;
  return 0 == hb_memcmp (arrayZ, o.arrayZ, length);
}
template <>
inline bool hb_array_t<const unsigned char>::operator == (const hb_array_t<const unsigned char> &o) const
{
  if (o.length != this->length) return false;
  return 0 == hb_memcmp (arrayZ, o.arrayZ, length);
}


/* Specialize hash() for byte arrays. */

template <>
inline uint32_t hb_array_t<const char>::hash () const
{
  // FNV-1a hash function
  uint32_t current = /*cbf29ce4*/0x84222325;
  unsigned i = 0;

#if defined(__OPTIMIZE__) && !defined(HB_NO_PACKED) && \
    ((defined(__GNUC__) && __GNUC__ >= 5) || defined(__clang__))
  struct __attribute__((packed)) packed_uint32_t { uint32_t v; };
  for (; i + 4 <= this->length; i += 4)
  {
    current = current ^ hb_hash ((uint32_t) ((const packed_uint32_t *) &this->arrayZ[i])->v);
    current = current * 16777619;
  }
#endif

  for (; i < this->length; i++)
  {
    current = current ^ hb_hash (this->arrayZ[i]);
    current = current * 16777619;
  }
  return current;
}

template <>
inline uint32_t hb_array_t<const unsigned char>::hash () const
{
  // FNV-1a hash function
  uint32_t current = /*cbf29ce4*/0x84222325;
  unsigned i = 0;

#if defined(__OPTIMIZE__) && !defined(HB_NO_PACKED) && \
    ((defined(__GNUC__) && __GNUC__ >= 5) || defined(__clang__))
  struct __attribute__((packed)) packed_uint32_t { uint32_t v; };
  for (; i + 4 <= this->length; i += 4)
  {
    current = current ^ hb_hash ((uint32_t) ((const packed_uint32_t *) &this->arrayZ[i])->v);
    current = current * 16777619;
  }
#endif

  for (; i < this->length; i++)
  {
    current = current ^ hb_hash (this->arrayZ[i]);
    current = current * 16777619;
  }
  return current;
}


typedef hb_array_t<const char> hb_bytes_t;
typedef hb_array_t<const unsigned char> hb_ubytes_t;



#endif /* HB_ARRAY_HH */