src/zlib/pvpgn_deflate.h

/* deflate.h -- internal compression state
 * Copyright (C) 1995-2002 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.
 */

#ifndef _DEFLATE_H
#define _DEFLATE_H

#include "common/setup_before.h"
#include "zlib/pvpgn_zutil.h"

/* ===========================================================================
 * Internal compression state.
 */

#define LENGTH_CODES 29
/* number of length codes, not counting the special END_BLOCK code */

#define LITERALS  256
/* number of literal bytes 0..255 */

#define L_CODES (LITERALS+1+LENGTH_CODES)
/* number of Literal or Length codes, including the END_BLOCK code */

#define D_CODES   30
/* number of distance codes */

#define BL_CODES  19
/* number of codes used to transfer the bit lengths */

#define HEAP_SIZE (2*L_CODES+1)
/* maximum heap size */

#define MAX_BITS 15
/* All codes must not exceed MAX_BITS bits */

#define INIT_STATE    42
#define BUSY_STATE   113
#define FINISH_STATE 666
/* Stream status */


/* Data structure describing a single value and its code string. */
typedef struct ct_data_s {
    union {
        ush  freq;       /* frequency count */
        ush  code;       /* bit string */
    } fc;
    union {
        ush  dad;        /* father node in Huffman tree */
        ush  len;        /* length of bit string */
    } dl;
} FAR ct_data;

#define Freq fc.freq
#define Code fc.code
#define Dad  dl.dad
#define Len  dl.len

typedef struct static_tree_desc_s  static_tree_desc;

typedef struct tree_desc_s {
    ct_data *dyn_tree;           /* the dynamic tree */
    int     max_code;            /* largest code with non zero frequency */
    static_tree_desc *stat_desc; /* the corresponding static tree */
} FAR tree_desc;

typedef ush Pos;
typedef Pos FAR Posf;
typedef unsigned IPos;

/* A Pos is an index in the character window. We use short instead of int to
 * save space in the various tables. IPos is used only for parameter passing.
 */

typedef struct internal_state {
    z_streamp strm;      /* pointer back to this zlib stream */
    int   status;        /* as the name implies */
    Bytef *pending_buf;  /* output still pending */
    ulg   pending_buf_size; /* size of pending_buf */
    Bytef *pending_out;  /* next pending byte to output to the stream */
    int   pending;       /* nb of bytes in the pending buffer */
    int   noheader;      /* suppress zlib header and adler32 */
    Byte  data_type;     /* UNKNOWN, BINARY or ASCII */
    Byte  method;        /* STORED (for zip only) or DEFLATED */
    int   last_flush;    /* value of flush param for previous deflate call */

                /* used by deflate.c: */

    uInt  w_size;        /* LZ77 window size (32K by default) */
    uInt  w_bits;        /* log2(w_size)  (8..16) */
    uInt  w_mask;        /* w_size - 1 */

    Bytef *window;
    /* Sliding window. Input bytes are read into the second half of the window,
     * and move to the first half later to keep a dictionary of at least wSize
     * bytes. With this organization, matches are limited to a distance of
     * wSize-MAX_MATCH bytes, but this ensures that IO is always
     * performed with a length multiple of the block size. Also, it limits
     * the window size to 64K, which is quite useful on MSDOS.
     * To do: use the user input buffer as sliding window.
     */

    ulg window_size;
    /* Actual size of window: 2*wSize, except when the user input buffer
     * is directly used as sliding window.
     */

    Posf *prev;
    /* Link to older string with same hash index. To limit the size of this
     * array to 64K, this link is maintained only for the last 32K strings.
     * An index in this array is thus a window index modulo 32K.
     */

    Posf *head; /* Heads of the hash chains or NIL. */

    uInt  ins_h;          /* hash index of string to be inserted */
    uInt  hash_size;      /* number of elements in hash table */
    uInt  hash_bits;      /* log2(hash_size) */
    uInt  hash_mask;      /* hash_size-1 */

    uInt  hash_shift;
    /* Number of bits by which ins_h must be shifted at each input
     * step. It must be such that after MIN_MATCH steps, the oldest
     * byte no longer takes part in the hash key, that is:
     *   hash_shift * MIN_MATCH >= hash_bits
     */

    long block_start;
    /* Window position at the beginning of the current output block. Gets
     * negative when the window is moved backwards.
     */

    uInt match_length;           /* length of best match */
    IPos prev_match;             /* previous match */
    int match_available;         /* set if previous match exists */
    uInt strstart;               /* start of string to insert */
    uInt match_start;            /* start of matching string */
    uInt lookahead;              /* number of valid bytes ahead in window */

    uInt prev_length;
    /* Length of the best match at previous step. Matches not greater than this
     * are discarded. This is used in the lazy match evaluation.
     */

    uInt max_chain_length;
    /* To speed up deflation, hash chains are never searched beyond this
     * length.  A higher limit improves compression ratio but degrades the
     * speed.
     */

    uInt max_lazy_match;
    /* Attempt to find a better match only when the current match is strictly
     * smaller than this value. This mechanism is used only for compression
     * levels >= 4.
     */
#   define max_insert_length  max_lazy_match
    /* Insert new strings in the hash table only if the match length is not
     * greater than this length. This saves time but degrades compression.
     * max_insert_length is used only for compression levels <= 3.
     */

    int level;    /* compression level (1..9) */
    int strategy; /* favor or force Huffman coding*/

    uInt good_match;
    /* Use a faster search when the previous match is longer than this */

    int nice_match; /* Stop searching when current match exceeds this */

                /* used by trees.c: */
    /* Didn't use ct_data typedef below to supress compiler warning */
    struct ct_data_s dyn_ltree[HEAP_SIZE];   /* literal and length tree */
    struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */
    struct ct_data_s bl_tree[2*BL_CODES+1];  /* Huffman tree for bit lengths */

    struct tree_desc_s l_desc;               /* desc. for literal tree */
    struct tree_desc_s d_desc;               /* desc. for distance tree */
    struct tree_desc_s bl_desc;              /* desc. for bit length tree */

    ush bl_count[MAX_BITS+1];
    /* number of codes at each bit length for an optimal tree */

    int heap[2*L_CODES+1];      /* heap used to build the Huffman trees */
    int heap_len;               /* number of elements in the heap */
    int heap_max;               /* element of largest frequency */
    /* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used.
     * 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
     *     when input comes from standard input.  (This can also be done for
     *     all blocks if lit_bufsize is not greater than 32K.)
     *   - if compression is not successful for a file smaller than 64K, we can
     *     even emit a stored file instead of a stored block (saving 5 bytes).
     *     This is applicable only for zip (not gzip or zlib).
     *   - creating new Huffman trees less frequently may not provide fast
     *     adaptation to changes in the input data statistics. (Take for
     *     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 */
    int last_eob_len;   /* bit length of EOB code for last block */

#ifdef DEBUG
    ulg compressed_len; /* total bit length of compressed file mod 2^32 */
    ulg bits_sent;      /* bit length of compressed data sent mod 2^32 */
#endif

    ush bi_buf;
    /* Output buffer. bits are inserted starting at the bottom (least
     * significant bits).
     */
    int bi_valid;
    /* Number of valid bits in bi_buf.  All bits above the last valid bit
     * are always zero.
     */

} FAR deflate_state;

/* Output a byte on the stream.
 * IN assertion: there is enough room in pending_buf.
 */
#define put_byte(s, c) {s->pending_buf[s->pending++] = (c);}


#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
/* Minimum amount of lookahead, except at the end of the input file.
 * See deflate.c for comments about the MIN_MATCH+1.
 */

#define MAX_DIST(s)  ((s)->w_size-MIN_LOOKAHEAD)
/* In order to simplify the code, particularly on 16 bit machines, match
 * distances are limited to MAX_DIST instead of WSIZE.
 */

        /* in trees.c */
void pvpgn_tr_init         OF((deflate_state *s));
int  pvpgn_tr_tally        OF((deflate_state *s, unsigned dist, unsigned lc));
void pvpgn_tr_flush_block  OF((deflate_state *s, charf *buf, ulg stored_len,
                          int eof));
void pvpgn_tr_align        OF((deflate_state *s));
void pvpgn_tr_stored_block OF((deflate_state *s, charf *buf, ulg stored_len,
                          int eof));

#define d_code(dist) \
   ((dist) < 256 ? pvpgn_dist_code[dist] : pvpgn_dist_code[256+((dist)>>7)])
/* Mapping from a distance to a distance code. dist is the distance - 1 and
 * must not have side effects. _dist_code[256] and _dist_code[257] are never
 * used.
 */

#ifndef DEBUG
/* Inline versions of _tr_tally for speed: */

#if defined(GEN_TREES_H) || !defined(STDC)
  extern uch pvpgn_length_code[];
  extern uch pvpgn_dist_code[];
#else
  extern const uch pvpgn_length_code[];
  extern const uch pvpgn_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 = (length); \
    ush dist = (distance); \
    s->d_buf[s->last_lit] = dist; \
    s->l_buf[s->last_lit++] = len; \
    dist--; \
    s->dyn_ltree[pvpgn_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
1	sysadm	1.1	/* deflate.h -- internal compression state
2			* Copyright (C) 1995-2002 Jean-loup Gailly
3			* For conditions of distribution and use, see copyright notice in zlib.h
4			*/
5
6			/* WARNING: this file should not be used by applications. It is
7			part of the implementation of the compression library and is
8			subject to change. Applications should only use zlib.h.
9			*/
10
11			#ifndef _DEFLATE_H
12			#define _DEFLATE_H
13
14			#include "common/setup_before.h"
15			#include "zlib/pvpgn_zutil.h"
16
17			/* ===========================================================================
18			* Internal compression state.
19			*/
20
21			#define LENGTH_CODES 29
22			/* number of length codes, not counting the special END_BLOCK code */
23
24			#define LITERALS 256
25			/* number of literal bytes 0..255 */
26
27			#define L_CODES (LITERALS+1+LENGTH_CODES)
28			/* number of Literal or Length codes, including the END_BLOCK code */
29
30			#define D_CODES 30
31			/* number of distance codes */
32
33			#define BL_CODES 19
34			/* number of codes used to transfer the bit lengths */
35
36			#define HEAP_SIZE (2*L_CODES+1)
37			/* maximum heap size */
38
39			#define MAX_BITS 15
40			/* All codes must not exceed MAX_BITS bits */
41
42			#define INIT_STATE 42
43			#define BUSY_STATE 113
44			#define FINISH_STATE 666
45			/* Stream status */
46
47
48			/* Data structure describing a single value and its code string. */
49			typedef struct ct_data_s {
50			union {
51			ush freq; /* frequency count */
52			ush code; /* bit string */
53			} fc;
54			union {
55			ush dad; /* father node in Huffman tree */
56			ush len; /* length of bit string */
57			} dl;
58			} FAR ct_data;
59
60			#define Freq fc.freq
61			#define Code fc.code
62			#define Dad dl.dad
63			#define Len dl.len
64
65			typedef struct static_tree_desc_s static_tree_desc;
66
67			typedef struct tree_desc_s {
68			ct_data dyn_tree; / the dynamic tree */
69			int max_code; /* largest code with non zero frequency */
70			static_tree_desc stat_desc; / the corresponding static tree */
71			} FAR tree_desc;
72
73			typedef ush Pos;
74			typedef Pos FAR Posf;
75			typedef unsigned IPos;
76
77			/* A Pos is an index in the character window. We use short instead of int to
78			* save space in the various tables. IPos is used only for parameter passing.
79			*/
80
81			typedef struct internal_state {
82			z_streamp strm; /* pointer back to this zlib stream */
83			int status; /* as the name implies */
84			Bytef pending_buf; / output still pending */
85			ulg pending_buf_size; /* size of pending_buf */
86			Bytef pending_out; / next pending byte to output to the stream */
87			int pending; /* nb of bytes in the pending buffer */
88			int noheader; /* suppress zlib header and adler32 */
89			Byte data_type; /* UNKNOWN, BINARY or ASCII */
90			Byte method; /* STORED (for zip only) or DEFLATED */
91			int last_flush; /* value of flush param for previous deflate call */
92
93			/* used by deflate.c: */
94
95			uInt w_size; /* LZ77 window size (32K by default) */
96			uInt w_bits; /* log2(w_size) (8..16) */
97			uInt w_mask; /* w_size - 1 */
98
99			Bytef *window;
100			/* Sliding window. Input bytes are read into the second half of the window,
101			* and move to the first half later to keep a dictionary of at least wSize
102			* bytes. With this organization, matches are limited to a distance of
103			* wSize-MAX_MATCH bytes, but this ensures that IO is always
104			* performed with a length multiple of the block size. Also, it limits
105			* the window size to 64K, which is quite useful on MSDOS.
106			* To do: use the user input buffer as sliding window.
107			*/
108
109			ulg window_size;
110			/* Actual size of window: 2*wSize, except when the user input buffer
111			* is directly used as sliding window.
112			*/
113
114			Posf *prev;
115			/* Link to older string with same hash index. To limit the size of this
116			* array to 64K, this link is maintained only for the last 32K strings.
117			* An index in this array is thus a window index modulo 32K.
118			*/
119
120			Posf head; / Heads of the hash chains or NIL. */
121
122			uInt ins_h; /* hash index of string to be inserted */
123			uInt hash_size; /* number of elements in hash table */
124			uInt hash_bits; /* log2(hash_size) */
125			uInt hash_mask; /* hash_size-1 */
126
127			uInt hash_shift;
128			/* Number of bits by which ins_h must be shifted at each input
129			* step. It must be such that after MIN_MATCH steps, the oldest
130			* byte no longer takes part in the hash key, that is:
131			* hash_shift * MIN_MATCH >= hash_bits
132			*/
133
134			long block_start;
135			/* Window position at the beginning of the current output block. Gets
136			* negative when the window is moved backwards.
137			*/
138
139			uInt match_length; /* length of best match */
140			IPos prev_match; /* previous match */
141			int match_available; /* set if previous match exists */
142			uInt strstart; /* start of string to insert */
143			uInt match_start; /* start of matching string */
144			uInt lookahead; /* number of valid bytes ahead in window */
145
146			uInt prev_length;
147			/* Length of the best match at previous step. Matches not greater than this
148			* are discarded. This is used in the lazy match evaluation.
149			*/
150
151			uInt max_chain_length;
152			/* To speed up deflation, hash chains are never searched beyond this
153			* length. A higher limit improves compression ratio but degrades the
154			* speed.
155			*/
156
157			uInt max_lazy_match;
158			/* Attempt to find a better match only when the current match is strictly
159			* smaller than this value. This mechanism is used only for compression
160			* levels >= 4.
161			*/
162			# define max_insert_length max_lazy_match
163			/* Insert new strings in the hash table only if the match length is not
164			* greater than this length. This saves time but degrades compression.
165			* max_insert_length is used only for compression levels <= 3.
166			*/
167
168			int level; /* compression level (1..9) */
169			int strategy; /* favor or force Huffman coding*/
170
171			uInt good_match;
172			/* Use a faster search when the previous match is longer than this */
173
174			int nice_match; /* Stop searching when current match exceeds this */
175
176			/* used by trees.c: */
177			/* Didn't use ct_data typedef below to supress compiler warning */
178			struct ct_data_s dyn_ltree[HEAP_SIZE]; /* literal and length tree */
179			struct ct_data_s dyn_dtree[2D_CODES+1]; / distance tree */
180			struct ct_data_s bl_tree[2BL_CODES+1]; / Huffman tree for bit lengths */
181
182			struct tree_desc_s l_desc; /* desc. for literal tree */
183			struct tree_desc_s d_desc; /* desc. for distance tree */
184			struct tree_desc_s bl_desc; /* desc. for bit length tree */
185
186			ush bl_count[MAX_BITS+1];
187			/* number of codes at each bit length for an optimal tree */
188
189			int heap[2L_CODES+1]; / heap used to build the Huffman trees */
190			int heap_len; /* number of elements in the heap */
191			int heap_max; /* element of largest frequency */
192			/* The sons of heap[n] are heap[2n] and heap[2n+1]. heap[0] is not used.
193			* The same heap array is used to build all trees.
194			*/
195
196			uch depth[2*L_CODES+1];
197			/* Depth of each subtree used as tie breaker for trees of equal frequency
198			*/
199
200			uchf l_buf; / buffer for literals or lengths */
201
202			uInt lit_bufsize;
203			/* Size of match buffer for literals/lengths. There are 4 reasons for
204			* limiting lit_bufsize to 64K:
205			* - frequencies can be kept in 16 bit counters
206			* - if compression is not successful for the first block, all input
207			* data is still in the window so we can still emit a stored block even
208			* when input comes from standard input. (This can also be done for
209			* all blocks if lit_bufsize is not greater than 32K.)
210			* - if compression is not successful for a file smaller than 64K, we can
211			* even emit a stored file instead of a stored block (saving 5 bytes).
212			* This is applicable only for zip (not gzip or zlib).
213			* - creating new Huffman trees less frequently may not provide fast
214			* adaptation to changes in the input data statistics. (Take for
215			* example a binary file with poorly compressible code followed by
216			* a highly compressible string table.) Smaller buffer sizes give
217			* fast adaptation but have of course the overhead of transmitting
218			* trees more frequently.
219			* - I can't count above 4
220			*/
221
222			uInt last_lit; /* running index in l_buf */
223
224			ushf *d_buf;
225			/* Buffer for distances. To simplify the code, d_buf and l_buf have
226			* the same number of elements. To use different lengths, an extra flag
227			* array would be necessary.
228			*/
229
230			ulg opt_len; /* bit length of current block with optimal trees */
231			ulg static_len; /* bit length of current block with static trees */
232			uInt matches; /* number of string matches in current block */
233			int last_eob_len; /* bit length of EOB code for last block */
234
235			#ifdef DEBUG
236			ulg compressed_len; /* total bit length of compressed file mod 2^32 */
237			ulg bits_sent; /* bit length of compressed data sent mod 2^32 */
238			#endif
239
240			ush bi_buf;
241			/* Output buffer. bits are inserted starting at the bottom (least
242			* significant bits).
243			*/
244			int bi_valid;
245			/* Number of valid bits in bi_buf. All bits above the last valid bit
246			* are always zero.
247			*/
248
249			} FAR deflate_state;
250
251			/* Output a byte on the stream.
252			* IN assertion: there is enough room in pending_buf.
253			*/
254			#define put_byte(s, c) {s->pending_buf[s->pending++] = (c);}
255
256
257			#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
258			/* Minimum amount of lookahead, except at the end of the input file.
259			* See deflate.c for comments about the MIN_MATCH+1.
260			*/
261
262			#define MAX_DIST(s) ((s)->w_size-MIN_LOOKAHEAD)
263			/* In order to simplify the code, particularly on 16 bit machines, match
264			* distances are limited to MAX_DIST instead of WSIZE.
265			*/
266
267			/* in trees.c */
268			void pvpgn_tr_init OF((deflate_state *s));
269			int pvpgn_tr_tally OF((deflate_state *s, unsigned dist, unsigned lc));
270			void pvpgn_tr_flush_block OF((deflate_state s, charf buf, ulg stored_len,
271			int eof));
272			void pvpgn_tr_align OF((deflate_state *s));
273			void pvpgn_tr_stored_block OF((deflate_state s, charf buf, ulg stored_len,
274			int eof));
275
276			#define d_code(dist) \
277			((dist) < 256 ? pvpgn_dist_code[dist] : pvpgn_dist_code[256+((dist)>>7)])
278			/* Mapping from a distance to a distance code. dist is the distance - 1 and
279			* must not have side effects. _dist_code[256] and _dist_code[257] are never
280			* used.
281			*/
282
283			#ifndef DEBUG
284			/* Inline versions of _tr_tally for speed: */
285
286			#if defined(GEN_TREES_H) \|\| !defined(STDC)
287			extern uch pvpgn_length_code[];
288			extern uch pvpgn_dist_code[];
289			#else
290			extern const uch pvpgn_length_code[];
291			extern const uch pvpgn_dist_code[];
292			#endif
293
294			# define _tr_tally_lit(s, c, flush) \
295			{ uch cc = (c); \
296			s->d_buf[s->last_lit] = 0; \
297			s->l_buf[s->last_lit++] = cc; \
298			s->dyn_ltree[cc].Freq++; \
299			flush = (s->last_lit == s->lit_bufsize-1); \
300			}
301			# define _tr_tally_dist(s, distance, length, flush) \
302			{ uch len = (length); \
303			ush dist = (distance); \
304			s->d_buf[s->last_lit] = dist; \
305			s->l_buf[s->last_lit++] = len; \
306			dist--; \
307			s->dyn_ltree[pvpgn_length_code[len]+LITERALS+1].Freq++; \
308			s->dyn_dtree[d_code(dist)].Freq++; \
309			flush = (s->last_lit == s->lit_bufsize-1); \
310			}
311			#else
312			# define _tr_tally_lit(s, c, flush) flush = _tr_tally(s, 0, c)
313			# define _tr_tally_dist(s, distance, length, flush) \
314			flush = _tr_tally(s, distance, length)
315			#endif
316
317			#endif
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