summaryrefslogtreecommitdiffstats
path: root/encoder_base.h
blob: ddba7e67b5156ca81d1772d382fcc24cb631f88b (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
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
/*  Lzlib - Compression library for the lzip format
    Copyright (C) 2009-2018 Antonio Diaz Diaz.

    This library is free software. Redistribution and use in source and
    binary forms, with or without modification, are permitted provided
    that the following conditions are met:

    1. Redistributions of source code must retain the above copyright
    notice, this list of conditions and the following disclaimer.

    2. Redistributions in binary form must reproduce the above copyright
    notice, this list of conditions and the following disclaimer in the
    documentation and/or other materials provided with the distribution.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*/

enum { price_shift_bits = 6,
       price_step_bits = 2 };

static const uint8_t dis_slots[1<<10] =
  {
   0,  1,  2,  3,  4,  4,  5,  5,  6,  6,  6,  6,  7,  7,  7,  7,
   8,  8,  8,  8,  8,  8,  8,  8,  9,  9,  9,  9,  9,  9,  9,  9,
  10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
  11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
  12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
  12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
  13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13,
  13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13,
  14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
  14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
  14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
  14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
  15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
  15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
  15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
  15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
  16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
  16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
  16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
  16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
  16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
  16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
  16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
  16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
  17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17,
  17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17,
  17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17,
  17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17,
  17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17,
  17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17,
  17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17,
  17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17,
  18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18,
  18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18,
  18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18,
  18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18,
  18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18,
  18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18,
  18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18,
  18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18,
  18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18,
  18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18,
  18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18,
  18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18,
  18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18,
  18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18,
  18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18,
  18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18,
  19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19,
  19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19,
  19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19,
  19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19,
  19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19,
  19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19,
  19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19,
  19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19,
  19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19,
  19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19,
  19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19,
  19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19,
  19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19,
  19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19,
  19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19,
  19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19 };

static inline uint8_t get_slot( const unsigned dis )
  {
  if( dis < (1 << 10) ) return dis_slots[dis];
  if( dis < (1 << 19) ) return dis_slots[dis>> 9] + 18;
  if( dis < (1 << 28) ) return dis_slots[dis>>18] + 36;
  return dis_slots[dis>>27] + 54;
  }


static const short prob_prices[bit_model_total >> price_step_bits] =
{
640, 539, 492, 461, 438, 419, 404, 390, 379, 369, 359, 351, 343, 336, 330, 323,
318, 312, 307, 302, 298, 293, 289, 285, 281, 277, 274, 270, 267, 264, 261, 258,
255, 252, 250, 247, 244, 242, 239, 237, 235, 232, 230, 228, 226, 224, 222, 220,
218, 216, 214, 213, 211, 209, 207, 206, 204, 202, 201, 199, 198, 196, 195, 193,
192, 190, 189, 188, 186, 185, 184, 182, 181, 180, 178, 177, 176, 175, 174, 172,
171, 170, 169, 168, 167, 166, 165, 164, 163, 162, 161, 159, 158, 157, 157, 156,
155, 154, 153, 152, 151, 150, 149, 148, 147, 146, 145, 145, 144, 143, 142, 141,
140, 140, 139, 138, 137, 136, 136, 135, 134, 133, 133, 132, 131, 130, 130, 129,
128, 127, 127, 126, 125, 125, 124, 123, 123, 122, 121, 121, 120, 119, 119, 118,
117, 117, 116, 115, 115, 114, 114, 113, 112, 112, 111, 111, 110, 109, 109, 108,
108, 107, 106, 106, 105, 105, 104, 104, 103, 103, 102, 101, 101, 100, 100,  99,
 99,  98,  98,  97,  97,  96,  96,  95,  95,  94,  94,  93,  93,  92,  92,  91,
 91,  90,  90,  89,  89,  88,  88,  88,  87,  87,  86,  86,  85,  85,  84,  84,
 83,  83,  83,  82,  82,  81,  81,  80,  80,  80,  79,  79,  78,  78,  77,  77,
 77,  76,  76,  75,  75,  75,  74,  74,  73,  73,  73,  72,  72,  71,  71,  71,
 70,  70,  70,  69,  69,  68,  68,  68,  67,  67,  67,  66,  66,  65,  65,  65,
 64,  64,  64,  63,  63,  63,  62,  62,  61,  61,  61,  60,  60,  60,  59,  59,
 59,  58,  58,  58,  57,  57,  57,  56,  56,  56,  55,  55,  55,  54,  54,  54,
 53,  53,  53,  53,  52,  52,  52,  51,  51,  51,  50,  50,  50,  49,  49,  49,
 48,  48,  48,  48,  47,  47,  47,  46,  46,  46,  45,  45,  45,  45,  44,  44,
 44,  43,  43,  43,  43,  42,  42,  42,  41,  41,  41,  41,  40,  40,  40,  40,
 39,  39,  39,  38,  38,  38,  38,  37,  37,  37,  37,  36,  36,  36,  35,  35,
 35,  35,  34,  34,  34,  34,  33,  33,  33,  33,  32,  32,  32,  32,  31,  31,
 31,  31,  30,  30,  30,  30,  29,  29,  29,  29,  28,  28,  28,  28,  27,  27,
 27,  27,  26,  26,  26,  26,  26,  25,  25,  25,  25,  24,  24,  24,  24,  23,
 23,  23,  23,  22,  22,  22,  22,  22,  21,  21,  21,  21,  20,  20,  20,  20,
 20,  19,  19,  19,  19,  18,  18,  18,  18,  18,  17,  17,  17,  17,  17,  16,
 16,  16,  16,  15,  15,  15,  15,  15,  14,  14,  14,  14,  14,  13,  13,  13,
 13,  13,  12,  12,  12,  12,  12,  11,  11,  11,  11,  10,  10,  10,  10,  10,
  9,   9,   9,   9,   9,   9,   8,   8,   8,   8,   8,   7,   7,   7,   7,   7,
  6,   6,   6,   6,   6,   5,   5,   5,   5,   5,   4,   4,   4,   4,   4,   4,
  3,   3,   3,   3,   3,   2,   2,   2,   2,   2,   1,   1,   1,   1,   1,   1 };

static inline int get_price( const int probability )
  { return prob_prices[probability >> price_step_bits]; }


static inline int price0( const Bit_model probability )
  { return get_price( probability ); }

static inline int price1( const Bit_model probability )
  { return get_price( bit_model_total - probability ); }

static inline int price_bit( const Bit_model bm, const bool bit )
  { return ( bit ? price1( bm ) : price0( bm ) ); }


static inline int price_symbol3( const Bit_model bm[], int symbol )
  {
  int price;
  bool bit = symbol & 1;
  symbol |= 8; symbol >>= 1;
  price = price_bit( bm[symbol], bit );
  bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit );
  return price + price_bit( bm[1], symbol & 1 );
  }


static inline int price_symbol6( const Bit_model bm[], unsigned symbol )
  {
  int price;
  bool bit = symbol & 1;
  symbol |= 64; symbol >>= 1;
  price = price_bit( bm[symbol], bit );
  bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit );
  bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit );
  bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit );
  bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit );
  return price + price_bit( bm[1], symbol & 1 );
  }


static inline int price_symbol8( const Bit_model bm[], int symbol )
  {
  int price;
  bool bit = symbol & 1;
  symbol |= 0x100; symbol >>= 1;
  price = price_bit( bm[symbol], bit );
  bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit );
  bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit );
  bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit );
  bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit );
  bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit );
  bit = symbol & 1; symbol >>= 1; price += price_bit( bm[symbol], bit );
  return price + price_bit( bm[1], symbol & 1 );
  }


static inline int price_symbol_reversed( const Bit_model bm[], int symbol,
                                         const int num_bits )
  {
  int price = 0;
  int model = 1;
  int i;
  for( i = num_bits; i > 0; --i )
    {
    const bool bit = symbol & 1;
    symbol >>= 1;
    price += price_bit( bm[model], bit );
    model = ( model << 1 ) | bit;
    }
  return price;
  }


static inline int price_matched( const Bit_model bm[], unsigned symbol,
                                 unsigned match_byte )
  {
  int price = 0;
  unsigned mask = 0x100;
  symbol |= mask;
  while( true )
    {
    const unsigned match_bit = ( match_byte <<= 1 ) & mask;
    const bool bit = ( symbol <<= 1 ) & 0x100;
    price += price_bit( bm[(symbol>>9)+match_bit+mask], bit );
    if( symbol >= 0x10000 ) return price;
    mask &= ~(match_bit ^ symbol);	/* if( match_bit != bit ) mask = 0; */
    }
  }


struct Matchfinder_base
  {
  unsigned long long partial_data_pos;
  uint8_t * buffer;		/* input buffer */
  int32_t * prev_positions;	/* 1 + last seen position of key. else 0 */
  int32_t * pos_array;		/* may be tree or chain */
  int before_size;		/* bytes to keep in buffer before dictionary */
  int after_size;		/* bytes to keep in buffer after pos */
  int buffer_size;
  int dictionary_size;		/* bytes to keep in buffer before pos */
  int pos;			/* current pos in buffer */
  int cyclic_pos;		/* cycles through [0, dictionary_size] */
  int stream_pos;		/* first byte not yet read from file */
  int pos_limit;		/* when reached, a new block must be read */
  int key4_mask;
  int num_prev_positions23;
  int num_prev_positions;	/* size of prev_positions */
  int pos_array_size;
  int saved_dictionary_size;	/* dictionary_size restored by Mb_reset */
  bool at_stream_end;		/* stream_pos shows real end of file */
  bool flushing;
  };

static bool Mb_normalize_pos( struct Matchfinder_base * const mb );

static bool Mb_init( struct Matchfinder_base * const mb, const int before_size,
                     const int dict_size, const int after_size,
                     const int dict_factor, const int num_prev_positions23,
                     const int pos_array_factor );

static inline void Mb_free( struct Matchfinder_base * const mb )
  { free( mb->prev_positions ); free( mb->buffer ); }

static inline uint8_t Mb_peek( const struct Matchfinder_base * const mb,
                               const int distance )
  { return mb->buffer[mb->pos-distance]; }

static inline int Mb_available_bytes( const struct Matchfinder_base * const mb )
  { return mb->stream_pos - mb->pos; }

static inline unsigned long long
Mb_data_position( const struct Matchfinder_base * const mb )
  { return mb->partial_data_pos + mb->pos; }

static inline void Mb_finish( struct Matchfinder_base * const mb )
  { mb->at_stream_end = true; mb->flushing = false; }

static inline bool Mb_data_finished( const struct Matchfinder_base * const mb )
  { return mb->at_stream_end && !mb->flushing && mb->pos >= mb->stream_pos; }

static inline bool Mb_flushing_or_end( const struct Matchfinder_base * const mb )
  { return mb->at_stream_end || mb->flushing; }

static inline int Mb_free_bytes( const struct Matchfinder_base * const mb )
  { if( Mb_flushing_or_end( mb ) ) return 0;
    return mb->buffer_size - mb->stream_pos; }

static inline bool Mb_enough_available_bytes( const struct Matchfinder_base * const mb )
  { return ( mb->pos + mb->after_size <= mb->stream_pos ||
             ( Mb_flushing_or_end( mb ) && mb->pos < mb->stream_pos ) ); }

static inline const uint8_t *
Mb_ptr_to_current_pos( const struct Matchfinder_base * const mb )
  { return mb->buffer + mb->pos; }

static int Mb_write_data( struct Matchfinder_base * const mb,
                          const uint8_t * const inbuf, const int size )
  {
  const int sz = min( mb->buffer_size - mb->stream_pos, size );
  if( Mb_flushing_or_end( mb ) || sz <= 0 ) return 0;
  memcpy( mb->buffer + mb->stream_pos, inbuf, sz );
  mb->stream_pos += sz;
  return sz;
  }

static inline int Mb_true_match_len( const struct Matchfinder_base * const mb,
                                     const int index, const int distance )
  {
  const uint8_t * const data = mb->buffer + mb->pos;
  int i = index;
  const int len_limit = min( Mb_available_bytes( mb ), max_match_len );
  while( i < len_limit && data[i-distance] == data[i] ) ++i;
  return i;
  }

static inline bool Mb_move_pos( struct Matchfinder_base * const mb )
  {
  if( ++mb->cyclic_pos > mb->dictionary_size ) mb->cyclic_pos = 0;
  if( ++mb->pos >= mb->pos_limit ) return Mb_normalize_pos( mb );
  return true;
  }


struct Range_encoder
  {
  struct Circular_buffer cb;
  unsigned min_free_bytes;
  uint64_t low;
  unsigned long long partial_member_pos;
  uint32_t range;
  unsigned ff_count;
  uint8_t cache;
  File_header header;
  };

static inline void Re_shift_low( struct Range_encoder * const renc )
  {
  if( renc->low >> 24 != 0xFF )
    {
    const bool carry = ( renc->low > 0xFFFFFFFFU );
    Cb_put_byte( &renc->cb, renc->cache + carry );
    for( ; renc->ff_count > 0; --renc->ff_count )
      Cb_put_byte( &renc->cb, 0xFF + carry );
    renc->cache = renc->low >> 24;
    }
  else ++renc->ff_count;
  renc->low = ( renc->low & 0x00FFFFFFU ) << 8;
  }

static inline void Re_reset( struct Range_encoder * const renc,
                             const unsigned dictionary_size )
  {
  int i;
  Cb_reset( &renc->cb );
  renc->low = 0;
  renc->partial_member_pos = 0;
  renc->range = 0xFFFFFFFFU;
  renc->ff_count = 0;
  renc->cache = 0;
  Fh_set_dictionary_size( renc->header, dictionary_size );
  for( i = 0; i < Fh_size; ++i )
    Cb_put_byte( &renc->cb, renc->header[i] );
  }

static inline bool Re_init( struct Range_encoder * const renc,
                            const unsigned dictionary_size,
                            const unsigned min_free_bytes )
  {
  if( !Cb_init( &renc->cb, 65536 + min_free_bytes ) ) return false;
  renc->min_free_bytes = min_free_bytes;
  Fh_set_magic( renc->header );
  Re_reset( renc, dictionary_size );
  return true;
  }

static inline void Re_free( struct Range_encoder * const renc )
  { Cb_free( &renc->cb ); }

static inline unsigned long long
Re_member_position( const struct Range_encoder * const renc )
  { return renc->partial_member_pos + Cb_used_bytes( &renc->cb ) + renc->ff_count; }

static inline bool Re_enough_free_bytes( const struct Range_encoder * const renc )
  { return Cb_free_bytes( &renc->cb ) >= renc->min_free_bytes + renc->ff_count; }

static inline int Re_read_data( struct Range_encoder * const renc,
                                uint8_t * const out_buffer, const int out_size )
  {
  const int size = Cb_read_data( &renc->cb, out_buffer, out_size );
  if( size > 0 ) renc->partial_member_pos += size;
  return size;
  }

static inline void Re_flush( struct Range_encoder * const renc )
  {
  int i; for( i = 0; i < 5; ++i ) Re_shift_low( renc );
  renc->low = 0;
  renc->range = 0xFFFFFFFFU;
  renc->ff_count = 0;
  renc->cache = 0;
  }

static inline void Re_encode( struct Range_encoder * const renc,
                              const int symbol, const int num_bits )
  {
  unsigned mask;
  for( mask = 1 << ( num_bits - 1 ); mask > 0; mask >>= 1 )
    {
    renc->range >>= 1;
    if( symbol & mask ) renc->low += renc->range;
    if( renc->range <= 0x00FFFFFFU )
      { renc->range <<= 8; Re_shift_low( renc ); }
    }
  }

static inline void Re_encode_bit( struct Range_encoder * const renc,
                                  Bit_model * const probability, const bool bit )
  {
  const uint32_t bound = ( renc->range >> bit_model_total_bits ) * *probability;
  if( !bit )
    {
    renc->range = bound;
    *probability += (bit_model_total - *probability) >> bit_model_move_bits;
    }
  else
    {
    renc->low += bound;
    renc->range -= bound;
    *probability -= *probability >> bit_model_move_bits;
    }
  if( renc->range <= 0x00FFFFFFU ) { renc->range <<= 8; Re_shift_low( renc ); }
  }

static inline void Re_encode_tree3( struct Range_encoder * const renc,
                                    Bit_model bm[], const int symbol )
  {
  int model = 1;
  bool bit = ( symbol >> 2 ) & 1;
  Re_encode_bit( renc, &bm[model], bit ); model = ( model << 1 ) | bit;
  bit = ( symbol >> 1 ) & 1;
  Re_encode_bit( renc, &bm[model], bit ); model = ( model << 1 ) | bit;
  Re_encode_bit( renc, &bm[model], symbol & 1 );
  }

static inline void Re_encode_tree6( struct Range_encoder * const renc,
                                    Bit_model bm[], const unsigned symbol )
  {
  int model = 1;
  bool bit = ( symbol >> 5 ) & 1;
  Re_encode_bit( renc, &bm[model], bit ); model = ( model << 1 ) | bit;
  bit = ( symbol >> 4 ) & 1;
  Re_encode_bit( renc, &bm[model], bit ); model = ( model << 1 ) | bit;
  bit = ( symbol >> 3 ) & 1;
  Re_encode_bit( renc, &bm[model], bit ); model = ( model << 1 ) | bit;
  bit = ( symbol >> 2 ) & 1;
  Re_encode_bit( renc, &bm[model], bit ); model = ( model << 1 ) | bit;
  bit = ( symbol >> 1 ) & 1;
  Re_encode_bit( renc, &bm[model], bit ); model = ( model << 1 ) | bit;
  Re_encode_bit( renc, &bm[model], symbol & 1 );
  }

static inline void Re_encode_tree8( struct Range_encoder * const renc,
                                    Bit_model bm[], const int symbol )
  {
  int model = 1;
  int i;
  for( i = 7; i >= 0; --i )
    {
    const bool bit = ( symbol >> i ) & 1;
    Re_encode_bit( renc, &bm[model], bit );
    model = ( model << 1 ) | bit;
    }
  }

static inline void Re_encode_tree_reversed( struct Range_encoder * const renc,
                     Bit_model bm[], int symbol, const int num_bits )
  {
  int model = 1;
  int i;
  for( i = num_bits; i > 0; --i )
    {
    const bool bit = symbol & 1;
    symbol >>= 1;
    Re_encode_bit( renc, &bm[model], bit );
    model = ( model << 1 ) | bit;
    }
  }

static inline void Re_encode_matched( struct Range_encoder * const renc,
                                      Bit_model bm[], unsigned symbol,
                                      unsigned match_byte )
  {
  unsigned mask = 0x100;
  symbol |= mask;
  while( true )
    {
    const unsigned match_bit = ( match_byte <<= 1 ) & mask;
    const bool bit = ( symbol <<= 1 ) & 0x100;
    Re_encode_bit( renc, &bm[(symbol>>9)+match_bit+mask], bit );
    if( symbol >= 0x10000 ) break;
    mask &= ~(match_bit ^ symbol);	/* if( match_bit != bit ) mask = 0; */
    }
  }

static inline void Re_encode_len( struct Range_encoder * const renc,
                                  struct Len_model * const lm,
                                  int symbol, const int pos_state )
  {
  bool bit = ( ( symbol -= min_match_len ) >= len_low_symbols );
  Re_encode_bit( renc, &lm->choice1, bit );
  if( !bit )
    Re_encode_tree3( renc, lm->bm_low[pos_state], symbol );
  else
    {
    bit = ( ( symbol -= len_low_symbols ) >= len_mid_symbols );
    Re_encode_bit( renc, &lm->choice2, bit );
    if( !bit )
      Re_encode_tree3( renc, lm->bm_mid[pos_state], symbol );
    else
      Re_encode_tree8( renc, lm->bm_high, symbol - len_mid_symbols );
    }
  }


enum { max_marker_size = 16,
       num_rep_distances = 4 };		/* must be 4 */

struct LZ_encoder_base
  {
  struct Matchfinder_base mb;
  unsigned long long member_size_limit;
  uint32_t crc;

  Bit_model bm_literal[1<<literal_context_bits][0x300];
  Bit_model bm_match[states][pos_states];
  Bit_model bm_rep[states];
  Bit_model bm_rep0[states];
  Bit_model bm_rep1[states];
  Bit_model bm_rep2[states];
  Bit_model bm_len[states][pos_states];
  Bit_model bm_dis_slot[len_states][1<<dis_slot_bits];
  Bit_model bm_dis[modeled_distances-end_dis_model+1];
  Bit_model bm_align[dis_align_size];
  struct Len_model match_len_model;
  struct Len_model rep_len_model;
  struct Range_encoder renc;
  int reps[num_rep_distances];
  State state;
  bool member_finished;
  };

static void LZeb_reset( struct LZ_encoder_base * const eb,
                        const unsigned long long member_size );

static inline bool LZeb_init( struct LZ_encoder_base * const eb,
                              const int before_size, const int dict_size,
                              const int after_size, const int dict_factor,
                              const int num_prev_positions23,
                              const int pos_array_factor,
                              const unsigned min_free_bytes,
                              const unsigned long long member_size )
  {
  if( !Mb_init( &eb->mb, before_size, dict_size, after_size, dict_factor,
                num_prev_positions23, pos_array_factor ) ) return false;
  if( !Re_init( &eb->renc, eb->mb.dictionary_size, min_free_bytes ) )
    return false;
  LZeb_reset( eb, member_size );
  return true;
  }

static inline bool LZeb_member_finished( const struct LZ_encoder_base * const eb )
  { return ( eb->member_finished && !Cb_used_bytes( &eb->renc.cb ) ); }

static inline void LZeb_free( struct LZ_encoder_base * const eb )
  { Re_free( &eb->renc ); Mb_free( &eb->mb ); }

static inline unsigned LZeb_crc( const struct LZ_encoder_base * const eb )
  { return eb->crc ^ 0xFFFFFFFFU; }

static inline int LZeb_price_literal( const struct LZ_encoder_base * const eb,
                            const uint8_t prev_byte, const uint8_t symbol )
  { return price_symbol8( eb->bm_literal[get_lit_state(prev_byte)], symbol ); }

static inline int LZeb_price_matched( const struct LZ_encoder_base * const eb,
  const uint8_t prev_byte, const uint8_t symbol, const uint8_t match_byte )
  { return price_matched( eb->bm_literal[get_lit_state(prev_byte)], symbol,
                          match_byte ); }

static inline void LZeb_encode_literal( struct LZ_encoder_base * const eb,
                            const uint8_t prev_byte, const uint8_t symbol )
  { Re_encode_tree8( &eb->renc, eb->bm_literal[get_lit_state(prev_byte)],
                     symbol ); }

static inline void LZeb_encode_matched( struct LZ_encoder_base * const eb,
  const uint8_t prev_byte, const uint8_t symbol, const uint8_t match_byte )
  { Re_encode_matched( &eb->renc, eb->bm_literal[get_lit_state(prev_byte)],
                       symbol, match_byte ); }

static inline void LZeb_encode_pair( struct LZ_encoder_base * const eb,
                                     const unsigned dis, const int len,
                                     const int pos_state )
  {
  const unsigned dis_slot = get_slot( dis );
  Re_encode_len( &eb->renc, &eb->match_len_model, len, pos_state );
  Re_encode_tree6( &eb->renc, eb->bm_dis_slot[get_len_state(len)], dis_slot );

  if( dis_slot >= start_dis_model )
    {
    const int direct_bits = ( dis_slot >> 1 ) - 1;
    const unsigned base = ( 2 | ( dis_slot & 1 ) ) << direct_bits;
    const unsigned direct_dis = dis - base;

    if( dis_slot < end_dis_model )
      Re_encode_tree_reversed( &eb->renc, eb->bm_dis + ( base - dis_slot ),
                               direct_dis, direct_bits );
    else
      {
      Re_encode( &eb->renc, direct_dis >> dis_align_bits,
                 direct_bits - dis_align_bits );
      Re_encode_tree_reversed( &eb->renc, eb->bm_align, direct_dis, dis_align_bits );
      }
    }
  }