diff options
author | maximius <none@none> | 2009-10-17 15:51:44 -0700 |
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committer | maximius <none@none> | 2009-10-17 15:51:44 -0700 |
commit | e585187b248f48b3c6e9247b49fa07c6565d65e5 (patch) | |
tree | 637c5b7ddacf41040bef4ea4f75a97da64c6a9bc /dep/src/zlib/deflate.h | |
parent | 26b5e033ffde3d161382fc9addbfa99738379641 (diff) |
*Backed out changeset 3be01fb200a5
--HG--
branch : trunk
Diffstat (limited to 'dep/src/zlib/deflate.h')
-rw-r--r-- | dep/src/zlib/deflate.h | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/dep/src/zlib/deflate.h b/dep/src/zlib/deflate.h index 8f3d217b13f..d56e97db4cb 100644 --- a/dep/src/zlib/deflate.h +++ b/dep/src/zlib/deflate.h @@ -2,14 +2,19 @@ * Copyright (C) 1995-2004 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. */ + /* @(#) $Id$ */ + #ifndef DEFLATE_H #define DEFLATE_H + #include "zutil.h" + /* define NO_GZIP when compiling if you want to disable gzip header and trailer creation by deflate(). NO_GZIP would be used to avoid linking in the crc code when it is not needed. For shared libraries, gzip encoding @@ -17,23 +22,32 @@ #ifndef NO_GZIP # define GZIP #endif + /* =========================================================================== * 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 EXTRA_STATE 69 #define NAME_STATE 73 @@ -43,6 +57,7 @@ #define FINISH_STATE 666 /* Stream status */ + /* Data structure describing a single value and its code string. */ typedef struct ct_data_s { union { @@ -54,22 +69,28 @@ typedef struct ct_data_s { 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 */ @@ -82,10 +103,13 @@ typedef struct internal_state { 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 @@ -95,45 +119,55 @@ typedef struct internal_state { * 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 @@ -144,31 +178,41 @@ typedef struct internal_state { * 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: @@ -188,20 +232,25 @@ typedef struct internal_state { * 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). @@ -210,20 +259,25 @@ typedef struct internal_state { /* 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 _tr_init OF((deflate_state *s)); int _tr_tally OF((deflate_state *s, unsigned dist, unsigned lc)); @@ -232,14 +286,17 @@ void _tr_flush_block OF((deflate_state *s, charf *buf, ulg stored_len, void _tr_align OF((deflate_state *s)); void _tr_stored_block OF((deflate_state *s, charf *buf, ulg stored_len, int eof)); + #define d_code(dist) \ ((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. */ + #ifndef DEBUG /* Inline versions of _tr_tally for speed: */ + #if defined(GEN_TREES_H) || !defined(STDC) extern uch _length_code[]; extern uch _dist_code[]; @@ -247,6 +304,7 @@ void _tr_stored_block OF((deflate_state *s, charf *buf, ulg stored_len, extern const uch _length_code[]; extern const uch _dist_code[]; #endif + # define _tr_tally_lit(s, c, flush) \ { uch cc = (c); \ s->d_buf[s->last_lit] = 0; \ @@ -269,5 +327,6 @@ void _tr_stored_block OF((deflate_state *s, charf *buf, ulg stored_len, # define _tr_tally_dist(s, distance, length, flush) \ flush = _tr_tally(s, distance, length) #endif + #endif /* DEFLATE_H */ |