summaryrefslogtreecommitdiffstatshomepage
path: root/src/lib/zlib/deflate.h
diff options
context:
space:
mode:
Diffstat (limited to 'src/lib/zlib/deflate.h')
-rw-r--r--src/lib/zlib/deflate.h408
1 files changed, 204 insertions, 204 deletions
diff --git a/src/lib/zlib/deflate.h b/src/lib/zlib/deflate.h
index fbac44d908e..4268aed349c 100644
--- a/src/lib/zlib/deflate.h
+++ b/src/lib/zlib/deflate.h
@@ -63,14 +63,14 @@
/* 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;
+ 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
@@ -81,9 +81,9 @@ typedef struct ct_data_s {
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 */
+ 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;
@@ -95,180 +95,180 @@ typedef unsigned IPos;
*/
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 */
- uInt pending; /* nb of bytes in the pending buffer */
- int wrap; /* bit 0 true for zlib, bit 1 true for gzip */
- gz_headerp gzhead; /* gzip header information to write */
- uInt gzindex; /* where in extra, name, or comment */
- 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.
- */
+ 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 */
+ uInt pending; /* nb of bytes in the pending buffer */
+ int wrap; /* bit 0 true for zlib, bit 1 true for gzip */
+ gz_headerp gzhead; /* gzip header information to write */
+ uInt gzindex; /* where in extra, name, or comment */
+ 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 suppress 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 */
- uInt insert; /* bytes at end of window left to insert */
+ /* 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 suppress 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 */
+ uInt insert; /* bytes at end of window left to insert */
#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 */
+ 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.
- */
-
- ulg high_water;
- /* High water mark offset in window for initialized bytes -- bytes above
- * this are set to zero in order to avoid memory check warnings when
- * longest match routines access bytes past the input. This is then
- * updated to the new high water mark.
- */
+ 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.
+ */
+
+ ulg high_water;
+ /* High water mark offset in window for initialized bytes -- bytes above
+ * this are set to zero in order to avoid memory check warnings when
+ * longest match routines access bytes past the input. This is then
+ * updated to the new high water mark.
+ */
} FAR deflate_state;
@@ -292,18 +292,18 @@ typedef struct internal_state {
/* Number of bytes after end of data in window to initialize in order to avoid
memory checker errors from longest match routines */
- /* in trees.c */
+ /* in trees.c */
void ZLIB_INTERNAL _tr_init OF((deflate_state *s));
int ZLIB_INTERNAL _tr_tally OF((deflate_state *s, unsigned dist, unsigned lc));
void ZLIB_INTERNAL _tr_flush_block OF((deflate_state *s, charf *buf,
- ulg stored_len, int last));
+ ulg stored_len, int last));
void ZLIB_INTERNAL _tr_flush_bits OF((deflate_state *s));
void ZLIB_INTERNAL _tr_align OF((deflate_state *s));
void ZLIB_INTERNAL _tr_stored_block OF((deflate_state *s, charf *buf,
- ulg stored_len, int last));
+ ulg stored_len, int last));
#define d_code(dist) \
- ((dist) < 256 ? _dist_code[dist] : _dist_code[256+((dist)>>7)])
+ ((dist) < 256 ? _dist_code[dist] : _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.
@@ -313,34 +313,34 @@ void ZLIB_INTERNAL _tr_stored_block OF((deflate_state *s, charf *buf,
/* Inline versions of _tr_tally for speed: */
#if defined(GEN_TREES_H) || !defined(STDC)
- extern uch ZLIB_INTERNAL _length_code[];
- extern uch ZLIB_INTERNAL _dist_code[];
+ extern uch ZLIB_INTERNAL _length_code[];
+ extern uch ZLIB_INTERNAL _dist_code[];
#else
- extern const uch ZLIB_INTERNAL _length_code[];
- extern const uch ZLIB_INTERNAL _dist_code[];
+ 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); \
- }
+ { 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[_length_code[len]+LITERALS+1].Freq++; \
- s->dyn_dtree[d_code(dist)].Freq++; \
- flush = (s->last_lit == s->lit_bufsize-1); \
- }
+ { uch len = (length); \
+ ush dist = (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)
+ flush = _tr_tally(s, distance, length)
#endif
#endif /* DEFLATE_H */