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/* deflate.h -- internal compression state
* Copyright (C) 1995-2016 Jean-loup Gailly
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* WARNING: this file should *not* be used by applications. It is
part of the implementation of the compression library and is
subject to change. Applications should only use zlib.h.
*/
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/* deflate.h -- internal compression state
* Copyright (C) 1995-2018 Jean-loup Gailly
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* WARNING: this file should *not* be used by applications. It is
part of the implementation of the compression library and is
subject to change. Applications should only use zlib.h.
*/
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* The same heap array is used to build all trees.
*/
uch depth[2*L_CODES+1];
/* Depth of each subtree used as tie breaker for trees of equal frequency
*/
uchf *l_buf; /* buffer for literals or lengths */
uInt lit_bufsize;
/* Size of match buffer for literals/lengths. There are 4 reasons for
* limiting lit_bufsize to 64K:
* - frequencies can be kept in 16 bit counters
* - if compression is not successful for the first block, all input
* data is still in the window so we can still emit a stored block even
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* The same heap array is used to build all trees.
*/
uch depth[2*L_CODES+1];
/* Depth of each subtree used as tie breaker for trees of equal frequency
*/
uchf *sym_buf; /* buffer for distances and literals/lengths */
uInt lit_bufsize;
/* Size of match buffer for literals/lengths. There are 4 reasons for
* limiting lit_bufsize to 64K:
* - frequencies can be kept in 16 bit counters
* - if compression is not successful for the first block, all input
* data is still in the window so we can still emit a stored block even
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* example a binary file with poorly compressible code followed by
* a highly compressible string table.) Smaller buffer sizes give
* fast adaptation but have of course the overhead of transmitting
* trees more frequently.
* - I can't count above 4
*/
uInt last_lit; /* running index in l_buf */
ushf *d_buf;
/* Buffer for distances. To simplify the code, d_buf and l_buf have
* the same number of elements. To use different lengths, an extra flag
* array would be necessary.
*/
ulg opt_len; /* bit length of current block with optimal trees */
ulg static_len; /* bit length of current block with static trees */
uInt matches; /* number of string matches in current block */
uInt insert; /* bytes at end of window left to insert */
#ifdef ZLIB_DEBUG
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* example a binary file with poorly compressible code followed by
* a highly compressible string table.) Smaller buffer sizes give
* fast adaptation but have of course the overhead of transmitting
* trees more frequently.
* - I can't count above 4
*/
uInt sym_next; /* running index in sym_buf */
uInt sym_end; /* symbol table full when sym_next reaches this */
ulg opt_len; /* bit length of current block with optimal trees */
ulg static_len; /* bit length of current block with static trees */
uInt matches; /* number of string matches in current block */
uInt insert; /* bytes at end of window left to insert */
#ifdef ZLIB_DEBUG
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#else
extern const uch ZLIB_INTERNAL _length_code[];
extern const uch ZLIB_INTERNAL _dist_code[];
#endif
# define _tr_tally_lit(s, c, flush) \
{ uch cc = (c); \
s->d_buf[s->last_lit] = 0; \
s->l_buf[s->last_lit++] = cc; \
s->dyn_ltree[cc].Freq++; \
flush = (s->last_lit == s->lit_bufsize-1); \
}
# define _tr_tally_dist(s, distance, length, flush) \
{ uch len = (uch)(length); \
ush dist = (ush)(distance); \
s->d_buf[s->last_lit] = dist; \
s->l_buf[s->last_lit++] = len; \
dist--; \
s->dyn_ltree[_length_code[len]+LITERALS+1].Freq++; \
s->dyn_dtree[d_code(dist)].Freq++; \
flush = (s->last_lit == s->lit_bufsize-1); \
}
#else
# define _tr_tally_lit(s, c, flush) flush = _tr_tally(s, 0, c)
# define _tr_tally_dist(s, distance, length, flush) \
flush = _tr_tally(s, distance, length)
#endif
#endif /* DEFLATE_H */
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#else
extern const uch ZLIB_INTERNAL _length_code[];
extern const uch ZLIB_INTERNAL _dist_code[];
#endif
# define _tr_tally_lit(s, c, flush) \
{ uch cc = (c); \
s->sym_buf[s->sym_next++] = 0; \
s->sym_buf[s->sym_next++] = 0; \
s->sym_buf[s->sym_next++] = cc; \
s->dyn_ltree[cc].Freq++; \
flush = (s->sym_next == s->sym_end); \
}
# define _tr_tally_dist(s, distance, length, flush) \
{ uch len = (uch)(length); \
ush dist = (ush)(distance); \
s->sym_buf[s->sym_next++] = dist; \
s->sym_buf[s->sym_next++] = dist >> 8; \
s->sym_buf[s->sym_next++] = len; \
dist--; \
s->dyn_ltree[_length_code[len]+LITERALS+1].Freq++; \
s->dyn_dtree[d_code(dist)].Freq++; \
flush = (s->sym_next == s->sym_end); \
}
#else
# define _tr_tally_lit(s, c, flush) flush = _tr_tally(s, 0, c)
# define _tr_tally_dist(s, distance, length, flush) \
flush = _tr_tally(s, distance, length)
#endif
#endif /* DEFLATE_H */
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