defutil.h
上传用户:jlfgdled
上传日期:2013-04-10
资源大小:33168k
文件大小:12k
- #define Assert(err, str)
- #define Trace(dummy)
- #define Tracev(dummy)
- #define Tracecv(err, dummy)
- #define Tracevv(dummy)
- #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 deflate_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 */
- ulg compressed_len; /* total bit length of compressed file */
- uInt matches; /* number of string matches in current block */
- int last_eob_len; /* bit length of EOB code for last block */
- #ifdef DEBUG_ZLIB
- ulg bits_sent; /* bit length of the compressed data */
- #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;
- typedef struct deflate_workspace {
- /* State memory for the deflator */
- deflate_state deflate_memory;
- Byte window_memory[2 * (1 << MAX_WBITS)];
- Pos prev_memory[1 << MAX_WBITS];
- Pos head_memory[1 << (MAX_MEM_LEVEL + 7)];
- char overlay_memory[(1 << (MAX_MEM_LEVEL + 6)) * (sizeof(ush)+2)];
- } deflate_workspace;
- /* 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 zlib_tr_init OF((deflate_state *s));
- int zlib_tr_tally OF((deflate_state *s, unsigned dist, unsigned lc));
- ulg zlib_tr_flush_block OF((deflate_state *s, charf *buf, ulg stored_len,
- int eof));
- void zlib_tr_align OF((deflate_state *s));
- void zlib_tr_stored_block OF((deflate_state *s, charf *buf, ulg stored_len,
- int eof));
- void zlib_tr_stored_type_only OF((deflate_state *));
- /* ===========================================================================
- * Output a short LSB first on the stream.
- * IN assertion: there is enough room in pendingBuf.
- */
- #define put_short(s, w) {
- put_byte(s, (uch)((w) & 0xff));
- put_byte(s, (uch)((ush)(w) >> 8));
- }
- /* ===========================================================================
- * Reverse the first len bits of a code, using straightforward code (a faster
- * method would use a table)
- * IN assertion: 1 <= len <= 15
- */
- static inline unsigned bi_reverse(unsigned code, /* the value to invert */
- int len) /* its bit length */
- {
- register unsigned res = 0;
- do {
- res |= code & 1;
- code >>= 1, res <<= 1;
- } while (--len > 0);
- return res >> 1;
- }
- /* ===========================================================================
- * Flush the bit buffer, keeping at most 7 bits in it.
- */
- static inline void bi_flush(deflate_state *s)
- {
- if (s->bi_valid == 16) {
- put_short(s, s->bi_buf);
- s->bi_buf = 0;
- s->bi_valid = 0;
- } else if (s->bi_valid >= 8) {
- put_byte(s, (Byte)s->bi_buf);
- s->bi_buf >>= 8;
- s->bi_valid -= 8;
- }
- }
- /* ===========================================================================
- * Flush the bit buffer and align the output on a byte boundary
- */
- static inline void bi_windup(deflate_state *s)
- {
- if (s->bi_valid > 8) {
- put_short(s, s->bi_buf);
- } else if (s->bi_valid > 0) {
- put_byte(s, (Byte)s->bi_buf);
- }
- s->bi_buf = 0;
- s->bi_valid = 0;
- #ifdef DEBUG_ZLIB
- s->bits_sent = (s->bits_sent+7) & ~7;
- #endif
- }