2 * This file is derived from various .h and .c files from the zlib-1.0.4
3 * distribution by Jean-loup Gailly and Mark Adler, with some additions
4 * by Paul Mackerras to aid in implementing Deflate compression and
5 * decompression for PPP packets. See zlib.h for conditions of
6 * distribution and use.
8 * Changes that have been made include:
9 * - added Z_PACKET_FLUSH (see zlib.h for details)
10 * - added inflateIncomp and deflateOutputPending
11 * - allow strm->next_out to be NULL, meaning discard the output
17 * ==FILEVERSION 971210==
19 * This marker is used by the Linux installation script to determine
20 * whether an up-to-date version of this file is already installed.
27 #if defined(__FreeBSD__) && defined(_KERNEL)
28 #define _tr_init zlib104_tr_init
29 #define _tr_align zlib104_tr_align
30 #define _tr_tally zlib104_tr_tally
31 #define _tr_flush_block zlib104_tr_flush_block
32 #define _tr_stored_block zlib104_tr_stored_block
33 #define inflate_fast zlib104_inflate_fast
34 #define inflate zlib104_inflate
35 #define zlibVersion zlib104_Version
41 * zutil.h -- internal interface and configuration of the compression library
42 * Copyright (C) 1995-1996 Jean-loup Gailly.
43 * For conditions of distribution and use, see copyright notice in zlib.h
46 /* WARNING: this file should *not* be used by applications. It is
47 part of the implementation of the compression library and is
48 subject to change. Applications should only use zlib.h.
51 /* From: zutil.h,v 1.16 1996/07/24 13:41:13 me Exp $ */
63 /* Assume this is a *BSD or SVR4 kernel */
64 #include <sys/types.h>
66 #include <sys/systm.h>
67 #include <sys/param.h>
71 #if defined(__KERNEL__)
72 /* Assume this is a Linux kernel */
73 #include <linux/string.h>
76 #else /* not kernel */
78 #if defined(MSDOS)||defined(VMS)||defined(CRAY)||defined(WIN32)||defined(RISCOS)
88 #endif /* __KERNEL__ */
94 /* compile with -Dlocal if your debugger can't find static symbols */
96 typedef unsigned char uch;
98 typedef unsigned short ush;
100 typedef unsigned long ulg;
102 static const char *z_errmsg[10]; /* indexed by 2-zlib_error */
103 /* (size given to avoid silly warnings with Visual C++) */
105 #define ERR_MSG(err) z_errmsg[Z_NEED_DICT-(err)]
107 #define ERR_RETURN(strm,err) \
108 return (strm->msg = (const char*)ERR_MSG(err), (err))
109 /* To be used only when the state is known to be valid */
111 /* common constants */
114 # define DEF_WBITS MAX_WBITS
116 /* default windowBits for decompression. MAX_WBITS is for compression only */
118 #if MAX_MEM_LEVEL >= 8
119 # define DEF_MEM_LEVEL 8
121 # define DEF_MEM_LEVEL MAX_MEM_LEVEL
123 /* default memLevel */
125 #define STORED_BLOCK 0
126 #define STATIC_TREES 1
128 /* The three kinds of block type */
131 #define MAX_MATCH 258
132 /* The minimum and maximum match lengths */
134 #define PRESET_DICT 0x20 /* preset dictionary flag in zlib header */
136 /* target dependencies */
139 # define OS_CODE 0x00
142 # else /* MSC or DJGPP */
148 # define OS_CODE 0x06
151 #ifdef WIN32 /* Window 95 & Windows NT */
152 # define OS_CODE 0x0b
155 #if defined(VAXC) || defined(VMS)
156 # define OS_CODE 0x02
157 # define FOPEN(name, mode) \
158 fopen((name), (mode), "mbc=60", "ctx=stm", "rfm=fix", "mrs=512")
162 # define OS_CODE 0x01
165 #if defined(ATARI) || defined(atarist)
166 # define OS_CODE 0x05
170 # define OS_CODE 0x07
173 #ifdef __50SERIES /* Prime/PRIMOS */
174 # define OS_CODE 0x0F
178 # define OS_CODE 0x0a
181 #if defined(_BEOS_) || defined(RISCOS)
182 # define fdopen(fd,mode) NULL /* No fdopen() */
185 /* Common defaults */
188 # define OS_CODE 0x03 /* assume Unix */
192 # define FOPEN(name, mode) fopen((name), (mode))
198 extern char *strerror OF((int));
199 # define zstrerror(errnum) strerror(errnum)
201 # define zstrerror(errnum) ""
207 #if (defined(M_I86SM) || defined(M_I86MM)) && !defined(_MSC_VER)
208 /* Use our own functions for small and medium model with MSC <= 5.0.
209 * You may have to use the same strategy for Borland C (untested).
213 #if defined(STDC) && !defined(HAVE_MEMCPY) && !defined(NO_MEMCPY)
217 # ifdef SMALL_MEDIUM /* MSDOS small or medium model */
218 # define zmemcpy _fmemcpy
219 # define zmemcmp _fmemcmp
220 # define zmemzero(dest, len) _fmemset(dest, 0, len)
222 # define zmemcpy memcpy
223 # define zmemcmp memcmp
224 # define zmemzero(dest, len) memset(dest, 0, len)
227 extern void zmemcpy OF((Bytef* dest, Bytef* source, uInt len));
228 extern int zmemcmp OF((Bytef* s1, Bytef* s2, uInt len));
229 extern void zmemzero OF((Bytef* dest, uInt len));
232 /* Diagnostic functions */
238 extern void z_error OF((char *m));
239 # define Assert(cond,msg) {if(!(cond)) z_error(msg);}
240 # define Trace(x) fprintf x
241 # define Tracev(x) {if (verbose) fprintf x ;}
242 # define Tracevv(x) {if (verbose>1) fprintf x ;}
243 # define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
244 # define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
246 # define Assert(cond,msg)
251 # define Tracecv(c,x)
255 typedef uLong (*check_func) OF((uLong check, const Bytef *buf, uInt len));
257 voidpf zcalloc OF((voidpf opaque, unsigned items, unsigned size));
258 void zcfree OF((voidpf opaque, voidpf ptr));
260 #define ZALLOC(strm, items, size) \
261 (*((strm)->zalloc))((strm)->opaque, (items), (size))
262 #define ZFREE(strm, addr) (*((strm)->zfree))((strm)->opaque, (voidpf)(addr))
263 #define TRY_FREE(s, p) {if (p) ZFREE(s, p);}
265 #endif /* _Z_UTIL_H */
269 /* deflate.h -- internal compression state
270 * Copyright (C) 1995-1996 Jean-loup Gailly
271 * For conditions of distribution and use, see copyright notice in zlib.h
274 /* WARNING: this file should *not* be used by applications. It is
275 part of the implementation of the compression library and is
276 subject to change. Applications should only use zlib.h.
279 /* From: deflate.h,v 1.10 1996/07/02 12:41:00 me Exp $ */
284 /* #include "zutil.h" */
286 /* ===========================================================================
287 * Internal compression state.
290 #define LENGTH_CODES 29
291 /* number of length codes, not counting the special END_BLOCK code */
294 /* number of literal bytes 0..255 */
296 #define L_CODES (LITERALS+1+LENGTH_CODES)
297 /* number of Literal or Length codes, including the END_BLOCK code */
300 /* number of distance codes */
303 /* number of codes used to transfer the bit lengths */
305 #define HEAP_SIZE (2*L_CODES+1)
306 /* maximum heap size */
309 /* All codes must not exceed MAX_BITS bits */
311 #define INIT_STATE 42
312 #define BUSY_STATE 113
313 #define FINISH_STATE 666
317 /* Data structure describing a single value and its code string. */
318 typedef struct ct_data_s {
320 ush freq; /* frequency count */
321 ush code; /* bit string */
324 ush dad; /* father node in Huffman tree */
325 ush len; /* length of bit string */
334 typedef struct static_tree_desc_s static_tree_desc;
336 typedef struct tree_desc_s {
337 ct_data *dyn_tree; /* the dynamic tree */
338 int max_code; /* largest code with non zero frequency */
339 static_tree_desc *stat_desc; /* the corresponding static tree */
343 typedef Pos FAR Posf;
344 typedef unsigned IPos;
346 /* A Pos is an index in the character window. We use short instead of int to
347 * save space in the various tables. IPos is used only for parameter passing.
350 typedef struct deflate_state {
351 z_streamp strm; /* pointer back to this zlib stream */
352 int status; /* as the name implies */
353 Bytef *pending_buf; /* output still pending */
354 ulg pending_buf_size; /* size of pending_buf */
355 Bytef *pending_out; /* next pending byte to output to the stream */
356 int pending; /* nb of bytes in the pending buffer */
357 int noheader; /* suppress zlib header and adler32 */
358 Byte data_type; /* UNKNOWN, BINARY or ASCII */
359 Byte method; /* STORED (for zip only) or DEFLATED */
360 int last_flush; /* value of flush param for previous deflate call */
362 /* used by deflate.c: */
364 uInt w_size; /* LZ77 window size (32K by default) */
365 uInt w_bits; /* log2(w_size) (8..16) */
366 uInt w_mask; /* w_size - 1 */
369 /* Sliding window. Input bytes are read into the second half of the window,
370 * and move to the first half later to keep a dictionary of at least wSize
371 * bytes. With this organization, matches are limited to a distance of
372 * wSize-MAX_MATCH bytes, but this ensures that IO is always
373 * performed with a length multiple of the block size. Also, it limits
374 * the window size to 64K, which is quite useful on MSDOS.
375 * To do: use the user input buffer as sliding window.
379 /* Actual size of window: 2*wSize, except when the user input buffer
380 * is directly used as sliding window.
384 /* Link to older string with same hash index. To limit the size of this
385 * array to 64K, this link is maintained only for the last 32K strings.
386 * An index in this array is thus a window index modulo 32K.
389 Posf *head; /* Heads of the hash chains or NIL. */
391 uInt ins_h; /* hash index of string to be inserted */
392 uInt hash_size; /* number of elements in hash table */
393 uInt hash_bits; /* log2(hash_size) */
394 uInt hash_mask; /* hash_size-1 */
397 /* Number of bits by which ins_h must be shifted at each input
398 * step. It must be such that after MIN_MATCH steps, the oldest
399 * byte no longer takes part in the hash key, that is:
400 * hash_shift * MIN_MATCH >= hash_bits
404 /* Window position at the beginning of the current output block. Gets
405 * negative when the window is moved backwards.
408 uInt match_length; /* length of best match */
409 IPos prev_match; /* previous match */
410 int match_available; /* set if previous match exists */
411 uInt strstart; /* start of string to insert */
412 uInt match_start; /* start of matching string */
413 uInt lookahead; /* number of valid bytes ahead in window */
416 /* Length of the best match at previous step. Matches not greater than this
417 * are discarded. This is used in the lazy match evaluation.
420 uInt max_chain_length;
421 /* To speed up deflation, hash chains are never searched beyond this
422 * length. A higher limit improves compression ratio but degrades the
427 /* Attempt to find a better match only when the current match is strictly
428 * smaller than this value. This mechanism is used only for compression
431 # define max_insert_length max_lazy_match
432 /* Insert new strings in the hash table only if the match length is not
433 * greater than this length. This saves time but degrades compression.
434 * max_insert_length is used only for compression levels <= 3.
437 int level; /* compression level (1..9) */
438 int strategy; /* favor or force Huffman coding*/
441 /* Use a faster search when the previous match is longer than this */
443 int nice_match; /* Stop searching when current match exceeds this */
445 /* used by trees.c: */
446 /* Didn't use ct_data typedef below to supress compiler warning */
447 struct ct_data_s dyn_ltree[HEAP_SIZE]; /* literal and length tree */
448 struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */
449 struct ct_data_s bl_tree[2*BL_CODES+1]; /* Huffman tree for bit lengths */
451 struct tree_desc_s l_desc; /* desc. for literal tree */
452 struct tree_desc_s d_desc; /* desc. for distance tree */
453 struct tree_desc_s bl_desc; /* desc. for bit length tree */
455 ush bl_count[MAX_BITS+1];
456 /* number of codes at each bit length for an optimal tree */
458 int heap[2*L_CODES+1]; /* heap used to build the Huffman trees */
459 int heap_len; /* number of elements in the heap */
460 int heap_max; /* element of largest frequency */
461 /* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used.
462 * The same heap array is used to build all trees.
465 uch depth[2*L_CODES+1];
466 /* Depth of each subtree used as tie breaker for trees of equal frequency
469 uchf *l_buf; /* buffer for literals or lengths */
472 /* Size of match buffer for literals/lengths. There are 4 reasons for
473 * limiting lit_bufsize to 64K:
474 * - frequencies can be kept in 16 bit counters
475 * - if compression is not successful for the first block, all input
476 * data is still in the window so we can still emit a stored block even
477 * when input comes from standard input. (This can also be done for
478 * all blocks if lit_bufsize is not greater than 32K.)
479 * - if compression is not successful for a file smaller than 64K, we can
480 * even emit a stored file instead of a stored block (saving 5 bytes).
481 * This is applicable only for zip (not gzip or zlib).
482 * - creating new Huffman trees less frequently may not provide fast
483 * adaptation to changes in the input data statistics. (Take for
484 * example a binary file with poorly compressible code followed by
485 * a highly compressible string table.) Smaller buffer sizes give
486 * fast adaptation but have of course the overhead of transmitting
487 * trees more frequently.
488 * - I can't count above 4
491 uInt last_lit; /* running index in l_buf */
494 /* Buffer for distances. To simplify the code, d_buf and l_buf have
495 * the same number of elements. To use different lengths, an extra flag
496 * array would be necessary.
499 ulg opt_len; /* bit length of current block with optimal trees */
500 ulg static_len; /* bit length of current block with static trees */
501 ulg compressed_len; /* total bit length of compressed file */
502 uInt matches; /* number of string matches in current block */
503 int last_eob_len; /* bit length of EOB code for last block */
506 ulg bits_sent; /* bit length of the compressed data */
510 /* Output buffer. bits are inserted starting at the bottom (least
514 /* Number of valid bits in bi_buf. All bits above the last valid bit
520 /* Output a byte on the stream.
521 * IN assertion: there is enough room in pending_buf.
523 #define put_byte(s, c) {s->pending_buf[s->pending++] = (c);}
526 #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
527 /* Minimum amount of lookahead, except at the end of the input file.
528 * See deflate.c for comments about the MIN_MATCH+1.
531 #define MAX_DIST(s) ((s)->w_size-MIN_LOOKAHEAD)
532 /* In order to simplify the code, particularly on 16 bit machines, match
533 * distances are limited to MAX_DIST instead of WSIZE.
537 void _tr_init OF((deflate_state *s));
538 int _tr_tally OF((deflate_state *s, unsigned dist, unsigned lc));
539 ulg _tr_flush_block OF((deflate_state *s, charf *buf, ulg stored_len,
541 void _tr_align OF((deflate_state *s));
542 void _tr_stored_block OF((deflate_state *s, charf *buf, ulg stored_len,
544 void _tr_stored_type_only OF((deflate_state *));
550 /* deflate.c -- compress data using the deflation algorithm
551 * Copyright (C) 1995-1996 Jean-loup Gailly.
552 * For conditions of distribution and use, see copyright notice in zlib.h
558 * The "deflation" process depends on being able to identify portions
559 * of the input text which are identical to earlier input (within a
560 * sliding window trailing behind the input currently being processed).
562 * The most straightforward technique turns out to be the fastest for
563 * most input files: try all possible matches and select the longest.
564 * The key feature of this algorithm is that insertions into the string
565 * dictionary are very simple and thus fast, and deletions are avoided
566 * completely. Insertions are performed at each input character, whereas
567 * string matches are performed only when the previous match ends. So it
568 * is preferable to spend more time in matches to allow very fast string
569 * insertions and avoid deletions. The matching algorithm for small
570 * strings is inspired from that of Rabin & Karp. A brute force approach
571 * is used to find longer strings when a small match has been found.
572 * A similar algorithm is used in comic (by Jan-Mark Wams) and freeze
573 * (by Leonid Broukhis).
574 * A previous version of this file used a more sophisticated algorithm
575 * (by Fiala and Greene) which is guaranteed to run in linear amortized
576 * time, but has a larger average cost, uses more memory and is patented.
577 * However the F&G algorithm may be faster for some highly redundant
578 * files if the parameter max_chain_length (described below) is too large.
582 * The idea of lazy evaluation of matches is due to Jan-Mark Wams, and
583 * I found it in 'freeze' written by Leonid Broukhis.
584 * Thanks to many people for bug reports and testing.
588 * Deutsch, L.P.,"DEFLATE Compressed Data Format Specification".
589 * Available in ftp://ds.internic.net/rfc/rfc1951.txt
591 * A description of the Rabin and Karp algorithm is given in the book
592 * "Algorithms" by R. Sedgewick, Addison-Wesley, p252.
594 * Fiala,E.R., and Greene,D.H.
595 * Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595
599 /* From: deflate.c,v 1.15 1996/07/24 13:40:58 me Exp $ */
601 /* #include "deflate.h" */
604 If you use the zlib library in a product, an acknowledgment is welcome
605 in the documentation of your product. If for some reason you cannot
606 include such an acknowledgment, I would appreciate that you keep this
607 copyright string in the executable of your product.
610 /* ===========================================================================
611 * Function prototypes.
614 need_more, /* block not completed, need more input or more output */
615 block_done, /* block flush performed */
616 finish_started, /* finish started, need only more output at next deflate */
617 finish_done /* finish done, accept no more input or output */
620 typedef block_state (*compress_func) OF((deflate_state *s, int flush));
621 /* Compression function. Returns the block state after the call. */
623 local void fill_window OF((deflate_state *s));
624 local block_state deflate_stored OF((deflate_state *s, int flush));
625 local block_state deflate_fast OF((deflate_state *s, int flush));
626 local block_state deflate_slow OF((deflate_state *s, int flush));
627 local void lm_init OF((deflate_state *s));
628 local void putShortMSB OF((deflate_state *s, uInt b));
629 local void flush_pending OF((z_streamp strm));
630 local int read_buf OF((z_streamp strm, charf *buf, unsigned size));
632 void match_init OF((void)); /* asm code initialization */
633 uInt longest_match OF((deflate_state *s, IPos cur_match));
635 local uInt longest_match OF((deflate_state *s, IPos cur_match));
639 local void check_match OF((deflate_state *s, IPos start, IPos match,
643 /* ===========================================================================
648 /* Tail of hash chains */
651 # define TOO_FAR 4096
653 /* Matches of length 3 are discarded if their distance exceeds TOO_FAR */
655 #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
656 /* Minimum amount of lookahead, except at the end of the input file.
657 * See deflate.c for comments about the MIN_MATCH+1.
660 /* Values for max_lazy_match, good_match and max_chain_length, depending on
661 * the desired pack level (0..9). The values given below have been tuned to
662 * exclude worst case performance for pathological files. Better values may be
663 * found for specific files.
665 typedef struct config_s {
666 ush good_length; /* reduce lazy search above this match length */
667 ush max_lazy; /* do not perform lazy search above this match length */
668 ush nice_length; /* quit search above this match length */
673 local config configuration_table[10] = {
674 /* good lazy nice chain */
675 /* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */
676 /* 1 */ {4, 4, 8, 4, deflate_fast}, /* maximum speed, no lazy matches */
677 /* 2 */ {4, 5, 16, 8, deflate_fast},
678 /* 3 */ {4, 6, 32, 32, deflate_fast},
680 /* 4 */ {4, 4, 16, 16, deflate_slow}, /* lazy matches */
681 /* 5 */ {8, 16, 32, 32, deflate_slow},
682 /* 6 */ {8, 16, 128, 128, deflate_slow},
683 /* 7 */ {8, 32, 128, 256, deflate_slow},
684 /* 8 */ {32, 128, 258, 1024, deflate_slow},
685 /* 9 */ {32, 258, 258, 4096, deflate_slow}}; /* maximum compression */
687 /* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4
688 * For deflate_fast() (levels <= 3) good is ignored and lazy has a different
693 /* result of memcmp for equal strings */
695 #ifndef NO_DUMMY_DECL
696 struct static_tree_desc_s {int dummy;}; /* for buggy compilers */
699 /* ===========================================================================
700 * Update a hash value with the given input byte
701 * IN assertion: all calls to to UPDATE_HASH are made with consecutive
702 * input characters, so that a running hash key can be computed from the
703 * previous key instead of complete recalculation each time.
705 #define UPDATE_HASH(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask)
708 /* ===========================================================================
709 * Insert string str in the dictionary and set match_head to the previous head
710 * of the hash chain (the most recent string with same hash key). Return
711 * the previous length of the hash chain.
712 * IN assertion: all calls to to INSERT_STRING are made with consecutive
713 * input characters and the first MIN_MATCH bytes of str are valid
714 * (except for the last MIN_MATCH-1 bytes of the input file).
716 #define INSERT_STRING(s, str, match_head) \
717 (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
718 s->prev[(str) & s->w_mask] = match_head = s->head[s->ins_h], \
719 s->head[s->ins_h] = (Pos)(str))
721 /* ===========================================================================
722 * Initialize the hash table (avoiding 64K overflow for 16 bit systems).
723 * prev[] will be initialized on the fly.
725 #define CLEAR_HASH(s) \
726 s->head[s->hash_size-1] = NIL; \
727 zmemzero((charf *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head));
729 /* ========================================================================= */
730 int deflateInit_(strm, level, version, stream_size)
736 return deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL,
737 Z_DEFAULT_STRATEGY, version, stream_size);
738 /* To do: ignore strm->next_in if we use it as window */
741 /* ========================================================================= */
742 int deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
743 version, stream_size)
755 static char* my_version = ZLIB_VERSION;
758 /* We overlay pending_buf and d_buf+l_buf. This works since the average
759 * output size for (length,distance) codes is <= 24 bits.
762 if (version == Z_NULL || version[0] != my_version[0] ||
763 stream_size != sizeof(z_stream)) {
764 return Z_VERSION_ERROR;
766 if (strm == Z_NULL) return Z_STREAM_ERROR;
770 if (strm->zalloc == Z_NULL) {
771 strm->zalloc = zcalloc;
772 strm->opaque = (voidpf)0;
774 if (strm->zfree == Z_NULL) strm->zfree = zcfree;
777 if (level == Z_DEFAULT_COMPRESSION) level = 6;
779 if (windowBits < 0) { /* undocumented feature: suppress zlib header */
781 windowBits = -windowBits;
783 if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED ||
784 windowBits < 9 || windowBits > 15 || level < 0 || level > 9 ||
785 strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
786 return Z_STREAM_ERROR;
788 s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state));
789 if (s == Z_NULL) return Z_MEM_ERROR;
790 strm->state = (struct internal_state FAR *)s;
793 s->noheader = noheader;
794 s->w_bits = windowBits;
795 s->w_size = 1 << s->w_bits;
796 s->w_mask = s->w_size - 1;
798 s->hash_bits = memLevel + 7;
799 s->hash_size = 1 << s->hash_bits;
800 s->hash_mask = s->hash_size - 1;
801 s->hash_shift = ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH);
803 s->window = (Bytef *) ZALLOC(strm, s->w_size, 2*sizeof(Byte));
804 s->prev = (Posf *) ZALLOC(strm, s->w_size, sizeof(Pos));
805 s->head = (Posf *) ZALLOC(strm, s->hash_size, sizeof(Pos));
807 s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */
809 overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2);
810 s->pending_buf = (uchf *) overlay;
811 s->pending_buf_size = (ulg)s->lit_bufsize * (sizeof(ush)+2L);
813 if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL ||
814 s->pending_buf == Z_NULL) {
815 strm->msg = (const char*)ERR_MSG(Z_MEM_ERROR);
819 s->d_buf = overlay + s->lit_bufsize/sizeof(ush);
820 s->l_buf = s->pending_buf + (1+sizeof(ush))*s->lit_bufsize;
823 s->strategy = strategy;
824 s->method = (Byte)method;
826 return deflateReset(strm);
829 /* ========================================================================= */
830 int deflateSetDictionary (strm, dictionary, dictLength)
832 const Bytef *dictionary;
836 uInt length = dictLength;
840 if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL)
841 return Z_STREAM_ERROR;
843 s = (deflate_state *) strm->state;
844 if (s->status != INIT_STATE) return Z_STREAM_ERROR;
846 strm->adler = adler32(strm->adler, dictionary, dictLength);
848 if (length < MIN_MATCH) return Z_OK;
849 if (length > MAX_DIST(s)) {
850 length = MAX_DIST(s);
851 #ifndef USE_DICT_HEAD
852 dictionary += dictLength - length; /* use the tail of the dictionary */
855 zmemcpy((charf *)s->window, dictionary, length);
856 s->strstart = length;
857 s->block_start = (long)length;
859 /* Insert all strings in the hash table (except for the last two bytes).
860 * s->lookahead stays null, so s->ins_h will be recomputed at the next
861 * call of fill_window.
863 s->ins_h = s->window[0];
864 UPDATE_HASH(s, s->ins_h, s->window[1]);
865 for (n = 0; n <= length - MIN_MATCH; n++) {
866 INSERT_STRING(s, n, hash_head);
868 if (hash_head) hash_head = 0; /* to make compiler happy */
872 /* ========================================================================= */
873 int deflateReset (strm)
878 if (strm == Z_NULL || strm->state == Z_NULL ||
879 strm->zalloc == Z_NULL || strm->zfree == Z_NULL) return Z_STREAM_ERROR;
881 strm->total_in = strm->total_out = 0;
882 strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */
883 strm->data_type = Z_UNKNOWN;
885 s = (deflate_state *)strm->state;
887 s->pending_out = s->pending_buf;
889 if (s->noheader < 0) {
890 s->noheader = 0; /* was set to -1 by deflate(..., Z_FINISH); */
892 s->status = s->noheader ? BUSY_STATE : INIT_STATE;
894 s->last_flush = Z_NO_FLUSH;
902 /* ========================================================================= */
903 int deflateParams(strm, level, strategy)
912 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
913 s = (deflate_state *) strm->state;
915 if (level == Z_DEFAULT_COMPRESSION) {
918 if (level < 0 || level > 9 || strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
919 return Z_STREAM_ERROR;
921 func = configuration_table[s->level].func;
923 if (func != configuration_table[level].func && strm->total_in != 0) {
924 /* Flush the last buffer: */
925 err = deflate(strm, Z_PARTIAL_FLUSH);
927 if (s->level != level) {
929 s->max_lazy_match = configuration_table[level].max_lazy;
930 s->good_match = configuration_table[level].good_length;
931 s->nice_match = configuration_table[level].nice_length;
932 s->max_chain_length = configuration_table[level].max_chain;
934 s->strategy = strategy;
938 /* =========================================================================
939 * Put a short in the pending buffer. The 16-bit value is put in MSB order.
940 * IN assertion: the stream state is correct and there is enough room in
943 local void putShortMSB (s, b)
947 put_byte(s, (Byte)(b >> 8));
948 put_byte(s, (Byte)(b & 0xff));
951 /* =========================================================================
952 * Flush as much pending output as possible. All deflate() output goes
953 * through this function so some applications may wish to modify it
954 * to avoid allocating a large strm->next_out buffer and copying into it.
955 * (See also read_buf()).
957 local void flush_pending(strm)
960 deflate_state *s = (deflate_state *) strm->state;
961 unsigned len = s->pending;
963 if (len > strm->avail_out) len = strm->avail_out;
964 if (len == 0) return;
966 if (strm->next_out != Z_NULL) {
967 zmemcpy(strm->next_out, s->pending_out, len);
968 strm->next_out += len;
970 s->pending_out += len;
971 strm->total_out += len;
972 strm->avail_out -= len;
974 if (s->pending == 0) {
975 s->pending_out = s->pending_buf;
979 /* ========================================================================= */
980 int deflate (strm, flush)
984 int old_flush; /* value of flush param for previous deflate call */
987 if (strm == Z_NULL || strm->state == Z_NULL ||
988 flush > Z_FINISH || flush < 0) {
989 return Z_STREAM_ERROR;
991 s = (deflate_state *) strm->state;
993 if ((strm->next_in == Z_NULL && strm->avail_in != 0) ||
994 (s->status == FINISH_STATE && flush != Z_FINISH)) {
995 ERR_RETURN(strm, Z_STREAM_ERROR);
997 if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR);
999 s->strm = strm; /* just in case */
1000 old_flush = s->last_flush;
1001 s->last_flush = flush;
1003 /* Write the zlib header */
1004 if (s->status == INIT_STATE) {
1006 uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8;
1007 uInt level_flags = (s->level-1) >> 1;
1009 if (level_flags > 3) level_flags = 3;
1010 header |= (level_flags << 6);
1011 if (s->strstart != 0) header |= PRESET_DICT;
1012 header += 31 - (header % 31);
1014 s->status = BUSY_STATE;
1015 putShortMSB(s, header);
1017 /* Save the adler32 of the preset dictionary: */
1018 if (s->strstart != 0) {
1019 putShortMSB(s, (uInt)(strm->adler >> 16));
1020 putShortMSB(s, (uInt)(strm->adler & 0xffff));
1025 /* Flush as much pending output as possible */
1026 if (s->pending != 0) {
1027 flush_pending(strm);
1028 if (strm->avail_out == 0) {
1029 /* Since avail_out is 0, deflate will be called again with
1030 * more output space, but possibly with both pending and
1031 * avail_in equal to zero. There won't be anything to do,
1032 * but this is not an error situation so make sure we
1033 * return OK instead of BUF_ERROR at next call of deflate:
1039 /* Make sure there is something to do and avoid duplicate consecutive
1040 * flushes. For repeated and useless calls with Z_FINISH, we keep
1041 * returning Z_STREAM_END instead of Z_BUFF_ERROR.
1043 } else if (strm->avail_in == 0 && flush <= old_flush &&
1044 flush != Z_FINISH) {
1045 ERR_RETURN(strm, Z_BUF_ERROR);
1048 /* User must not provide more input after the first FINISH: */
1049 if (s->status == FINISH_STATE && strm->avail_in != 0) {
1050 ERR_RETURN(strm, Z_BUF_ERROR);
1053 /* Start a new block or continue the current one.
1055 if (strm->avail_in != 0 || s->lookahead != 0 ||
1056 (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) {
1059 bstate = (*(configuration_table[s->level].func))(s, flush);
1061 if (bstate == finish_started || bstate == finish_done) {
1062 s->status = FINISH_STATE;
1064 if (bstate == need_more || bstate == finish_started) {
1065 if (strm->avail_out == 0) {
1066 s->last_flush = -1; /* avoid BUF_ERROR next call, see above */
1069 /* If flush != Z_NO_FLUSH && avail_out == 0, the next call
1070 * of deflate should use the same flush parameter to make sure
1071 * that the flush is complete. So we don't have to output an
1072 * empty block here, this will be done at next call. This also
1073 * ensures that for a very small output buffer, we emit at most
1077 if (bstate == block_done) {
1078 if (flush == Z_PARTIAL_FLUSH) {
1080 } else if (flush == Z_PACKET_FLUSH) {
1081 /* Output just the 3-bit `stored' block type value,
1082 but not a zero length. */
1083 _tr_stored_type_only(s);
1084 } else { /* FULL_FLUSH or SYNC_FLUSH */
1085 _tr_stored_block(s, (char*)0, 0L, 0);
1086 /* For a full flush, this empty block will be recognized
1087 * as a special marker by inflate_sync().
1089 if (flush == Z_FULL_FLUSH) {
1090 CLEAR_HASH(s); /* forget history */
1093 flush_pending(strm);
1094 if (strm->avail_out == 0) {
1095 s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */
1100 Assert(strm->avail_out > 0, "bug2");
1102 if (flush != Z_FINISH) return Z_OK;
1103 if (s->noheader) return Z_STREAM_END;
1105 /* Write the zlib trailer (adler32) */
1106 putShortMSB(s, (uInt)(strm->adler >> 16));
1107 putShortMSB(s, (uInt)(strm->adler & 0xffff));
1108 flush_pending(strm);
1109 /* If avail_out is zero, the application will call deflate again
1110 * to flush the rest.
1112 s->noheader = -1; /* write the trailer only once! */
1113 return s->pending != 0 ? Z_OK : Z_STREAM_END;
1116 /* ========================================================================= */
1117 int deflateEnd (strm)
1123 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
1124 s = (deflate_state *) strm->state;
1127 if (status != INIT_STATE && status != BUSY_STATE &&
1128 status != FINISH_STATE) {
1129 return Z_STREAM_ERROR;
1132 /* Deallocate in reverse order of allocations: */
1133 TRY_FREE(strm, s->pending_buf);
1134 TRY_FREE(strm, s->head);
1135 TRY_FREE(strm, s->prev);
1136 TRY_FREE(strm, s->window);
1139 strm->state = Z_NULL;
1141 return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK;
1144 /* =========================================================================
1145 * Copy the source state to the destination state.
1147 int deflateCopy (dest, source)
1155 if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL)
1156 return Z_STREAM_ERROR;
1157 ss = (deflate_state *) source->state;
1159 zmemcpy(dest, source, sizeof(*dest));
1161 ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state));
1162 if (ds == Z_NULL) return Z_MEM_ERROR;
1163 dest->state = (struct internal_state FAR *) ds;
1164 zmemcpy(ds, ss, sizeof(*ds));
1167 ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte));
1168 ds->prev = (Posf *) ZALLOC(dest, ds->w_size, sizeof(Pos));
1169 ds->head = (Posf *) ZALLOC(dest, ds->hash_size, sizeof(Pos));
1170 overlay = (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2);
1171 ds->pending_buf = (uchf *) overlay;
1173 if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL ||
1174 ds->pending_buf == Z_NULL) {
1178 /* ??? following zmemcpy doesn't work for 16-bit MSDOS */
1179 zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte));
1180 zmemcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos));
1181 zmemcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos));
1182 zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size);
1184 ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf);
1185 ds->d_buf = overlay + ds->lit_bufsize/sizeof(ush);
1186 ds->l_buf = ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize;
1188 ds->l_desc.dyn_tree = ds->dyn_ltree;
1189 ds->d_desc.dyn_tree = ds->dyn_dtree;
1190 ds->bl_desc.dyn_tree = ds->bl_tree;
1195 /* ===========================================================================
1196 * Return the number of bytes of output which are immediately available
1197 * for output from the decompressor.
1199 int deflateOutputPending (strm)
1202 if (strm == Z_NULL || strm->state == Z_NULL) return 0;
1204 return ((deflate_state *)(strm->state))->pending;
1207 /* ===========================================================================
1208 * Read a new buffer from the current input stream, update the adler32
1209 * and total number of bytes read. All deflate() input goes through
1210 * this function so some applications may wish to modify it to avoid
1211 * allocating a large strm->next_in buffer and copying from it.
1212 * (See also flush_pending()).
1214 local int read_buf(strm, buf, size)
1219 unsigned len = strm->avail_in;
1221 if (len > size) len = size;
1222 if (len == 0) return 0;
1224 strm->avail_in -= len;
1226 if (!((deflate_state *)(strm->state))->noheader) {
1227 strm->adler = adler32(strm->adler, strm->next_in, len);
1229 zmemcpy(buf, strm->next_in, len);
1230 strm->next_in += len;
1231 strm->total_in += len;
1236 /* ===========================================================================
1237 * Initialize the "longest match" routines for a new zlib stream
1239 local void lm_init (s)
1242 s->window_size = (ulg)2L*s->w_size;
1246 /* Set the default configuration parameters:
1248 s->max_lazy_match = configuration_table[s->level].max_lazy;
1249 s->good_match = configuration_table[s->level].good_length;
1250 s->nice_match = configuration_table[s->level].nice_length;
1251 s->max_chain_length = configuration_table[s->level].max_chain;
1254 s->block_start = 0L;
1256 s->match_length = s->prev_length = MIN_MATCH-1;
1257 s->match_available = 0;
1260 match_init(); /* initialize the asm code */
1264 /* ===========================================================================
1265 * Set match_start to the longest match starting at the given string and
1266 * return its length. Matches shorter or equal to prev_length are discarded,
1267 * in which case the result is equal to prev_length and match_start is
1269 * IN assertions: cur_match is the head of the hash chain for the current
1270 * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
1271 * OUT assertion: the match length is not greater than s->lookahead.
1274 /* For 80x86 and 680x0, an optimized version will be provided in match.asm or
1275 * match.S. The code will be functionally equivalent.
1277 local uInt longest_match(s, cur_match)
1279 IPos cur_match; /* current match */
1281 unsigned chain_length = s->max_chain_length;/* max hash chain length */
1282 Bytef *scan = s->window + s->strstart; /* current string */
1283 Bytef *match; /* matched string */
1284 int len; /* length of current match */
1285 int best_len = s->prev_length; /* best match length so far */
1286 int nice_match = s->nice_match; /* stop if match long enough */
1287 IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
1288 s->strstart - (IPos)MAX_DIST(s) : NIL;
1289 /* Stop when cur_match becomes <= limit. To simplify the code,
1290 * we prevent matches with the string of window index 0.
1292 Posf *prev = s->prev;
1293 uInt wmask = s->w_mask;
1296 /* Compare two bytes at a time. Note: this is not always beneficial.
1297 * Try with and without -DUNALIGNED_OK to check.
1299 Bytef *strend = s->window + s->strstart + MAX_MATCH - 1;
1300 ush scan_start = *(ushf*)scan;
1301 ush scan_end = *(ushf*)(scan+best_len-1);
1303 Bytef *strend = s->window + s->strstart + MAX_MATCH;
1304 Byte scan_end1 = scan[best_len-1];
1305 Byte scan_end = scan[best_len];
1308 /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
1309 * It is easy to get rid of this optimization if necessary.
1311 Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
1313 /* Do not waste too much time if we already have a good match: */
1314 if (s->prev_length >= s->good_match) {
1317 /* Do not look for matches beyond the end of the input. This is necessary
1318 * to make deflate deterministic.
1320 if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;
1322 Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
1325 Assert(cur_match < s->strstart, "no future");
1326 match = s->window + cur_match;
1328 /* Skip to next match if the match length cannot increase
1329 * or if the match length is less than 2:
1331 #if (defined(UNALIGNED_OK) && MAX_MATCH == 258)
1332 /* This code assumes sizeof(unsigned short) == 2. Do not use
1333 * UNALIGNED_OK if your compiler uses a different size.
1335 if (*(ushf*)(match+best_len-1) != scan_end ||
1336 *(ushf*)match != scan_start) continue;
1338 /* It is not necessary to compare scan[2] and match[2] since they are
1339 * always equal when the other bytes match, given that the hash keys
1340 * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at
1341 * strstart+3, +5, ... up to strstart+257. We check for insufficient
1342 * lookahead only every 4th comparison; the 128th check will be made
1343 * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is
1344 * necessary to put more guard bytes at the end of the window, or
1345 * to check more often for insufficient lookahead.
1347 Assert(scan[2] == match[2], "scan[2]?");
1350 } while (*(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1351 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1352 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1353 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1355 /* The funny "do {}" generates better code on most compilers */
1357 /* Here, scan <= window+strstart+257 */
1358 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1359 if (*scan == *match) scan++;
1361 len = (MAX_MATCH - 1) - (int)(strend-scan);
1362 scan = strend - (MAX_MATCH-1);
1364 #else /* UNALIGNED_OK */
1366 if (match[best_len] != scan_end ||
1367 match[best_len-1] != scan_end1 ||
1369 *++match != scan[1]) continue;
1371 /* The check at best_len-1 can be removed because it will be made
1372 * again later. (This heuristic is not always a win.)
1373 * It is not necessary to compare scan[2] and match[2] since they
1374 * are always equal when the other bytes match, given that
1375 * the hash keys are equal and that HASH_BITS >= 8.
1378 Assert(*scan == *match, "match[2]?");
1380 /* We check for insufficient lookahead only every 8th comparison;
1381 * the 256th check will be made at strstart+258.
1384 } while (*++scan == *++match && *++scan == *++match &&
1385 *++scan == *++match && *++scan == *++match &&
1386 *++scan == *++match && *++scan == *++match &&
1387 *++scan == *++match && *++scan == *++match &&
1390 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1392 len = MAX_MATCH - (int)(strend - scan);
1393 scan = strend - MAX_MATCH;
1395 #endif /* UNALIGNED_OK */
1397 if (len > best_len) {
1398 s->match_start = cur_match;
1400 if (len >= nice_match) break;
1402 scan_end = *(ushf*)(scan+best_len-1);
1404 scan_end1 = scan[best_len-1];
1405 scan_end = scan[best_len];
1408 } while ((cur_match = prev[cur_match & wmask]) > limit
1409 && --chain_length != 0);
1411 if ((uInt)best_len <= s->lookahead) return best_len;
1412 return s->lookahead;
1417 /* ===========================================================================
1418 * Check that the match at match_start is indeed a match.
1420 local void check_match(s, start, match, length)
1425 /* check that the match is indeed a match */
1426 if (zmemcmp((charf *)s->window + match,
1427 (charf *)s->window + start, length) != EQUAL) {
1428 fprintf(stderr, " start %u, match %u, length %d\n",
1429 start, match, length);
1431 fprintf(stderr, "%c%c", s->window[match++], s->window[start++]);
1432 } while (--length != 0);
1433 z_error("invalid match");
1435 if (z_verbose > 1) {
1436 fprintf(stderr,"\\[%d,%d]", start-match, length);
1437 do { putc(s->window[start++], stderr); } while (--length != 0);
1441 # define check_match(s, start, match, length)
1444 /* ===========================================================================
1445 * Fill the window when the lookahead becomes insufficient.
1446 * Updates strstart and lookahead.
1448 * IN assertion: lookahead < MIN_LOOKAHEAD
1449 * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD
1450 * At least one byte has been read, or avail_in == 0; reads are
1451 * performed for at least two bytes (required for the zip translate_eol
1452 * option -- not supported here).
1454 local void fill_window(s)
1459 unsigned more; /* Amount of free space at the end of the window. */
1460 uInt wsize = s->w_size;
1463 more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart);
1465 /* Deal with !@#$% 64K limit: */
1466 if (more == 0 && s->strstart == 0 && s->lookahead == 0) {
1469 } else if (more == (unsigned)(-1)) {
1470 /* Very unlikely, but possible on 16 bit machine if strstart == 0
1471 * and lookahead == 1 (input done one byte at time)
1475 /* If the window is almost full and there is insufficient lookahead,
1476 * move the upper half to the lower one to make room in the upper half.
1478 } else if (s->strstart >= wsize+MAX_DIST(s)) {
1480 zmemcpy((charf *)s->window, (charf *)s->window+wsize,
1482 s->match_start -= wsize;
1483 s->strstart -= wsize; /* we now have strstart >= MAX_DIST */
1484 s->block_start -= (long) wsize;
1486 /* Slide the hash table (could be avoided with 32 bit values
1487 at the expense of memory usage). We slide even when level == 0
1488 to keep the hash table consistent if we switch back to level > 0
1489 later. (Using level 0 permanently is not an optimal usage of
1490 zlib, so we don't care about this pathological case.)
1496 *p = (Pos)(m >= wsize ? m-wsize : NIL);
1503 *p = (Pos)(m >= wsize ? m-wsize : NIL);
1504 /* If n is not on any hash chain, prev[n] is garbage but
1505 * its value will never be used.
1510 if (s->strm->avail_in == 0) return;
1512 /* If there was no sliding:
1513 * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 &&
1514 * more == window_size - lookahead - strstart
1515 * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1)
1516 * => more >= window_size - 2*WSIZE + 2
1517 * In the BIG_MEM or MMAP case (not yet supported),
1518 * window_size == input_size + MIN_LOOKAHEAD &&
1519 * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD.
1520 * Otherwise, window_size == 2*WSIZE so more >= 2.
1521 * If there was sliding, more >= WSIZE. So in all cases, more >= 2.
1523 Assert(more >= 2, "more < 2");
1525 n = read_buf(s->strm, (charf *)s->window + s->strstart + s->lookahead,
1529 /* Initialize the hash value now that we have some input: */
1530 if (s->lookahead >= MIN_MATCH) {
1531 s->ins_h = s->window[s->strstart];
1532 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
1534 Call UPDATE_HASH() MIN_MATCH-3 more times
1537 /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage,
1538 * but this is not important since only literal bytes will be emitted.
1541 } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0);
1544 /* ===========================================================================
1545 * Flush the current block, with given end-of-file flag.
1546 * IN assertion: strstart is set to the end of the current match.
1548 #define FLUSH_BLOCK_ONLY(s, eof) { \
1549 _tr_flush_block(s, (s->block_start >= 0L ? \
1550 (charf *)&s->window[(unsigned)s->block_start] : \
1552 (ulg)((long)s->strstart - s->block_start), \
1554 s->block_start = s->strstart; \
1555 flush_pending(s->strm); \
1556 Tracev((stderr,"[FLUSH]")); \
1559 /* Same but force premature exit if necessary. */
1560 #define FLUSH_BLOCK(s, eof) { \
1561 FLUSH_BLOCK_ONLY(s, eof); \
1562 if (s->strm->avail_out == 0) return (eof) ? finish_started : need_more; \
1565 /* ===========================================================================
1566 * Copy without compression as much as possible from the input stream, return
1567 * the current block state.
1568 * This function does not insert new strings in the dictionary since
1569 * uncompressible data is probably not useful. This function is used
1570 * only for the level=0 compression option.
1571 * NOTE: this function should be optimized to avoid extra copying from
1572 * window to pending_buf.
1574 local block_state deflate_stored(s, flush)
1578 /* Stored blocks are limited to 0xffff bytes, pending_buf is limited
1579 * to pending_buf_size, and each stored block has a 5 byte header:
1581 ulg max_block_size = 0xffff;
1584 if (max_block_size > s->pending_buf_size - 5) {
1585 max_block_size = s->pending_buf_size - 5;
1588 /* Copy as much as possible from input to output: */
1590 /* Fill the window as much as possible: */
1591 if (s->lookahead <= 1) {
1593 Assert(s->strstart < s->w_size+MAX_DIST(s) ||
1594 s->block_start >= (long)s->w_size, "slide too late");
1597 if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more;
1599 if (s->lookahead == 0) break; /* flush the current block */
1601 Assert(s->block_start >= 0L, "block gone");
1603 s->strstart += s->lookahead;
1606 /* Emit a stored block if pending_buf will be full: */
1607 max_start = s->block_start + max_block_size;
1608 if (s->strstart == 0 || (ulg)s->strstart >= max_start) {
1609 /* strstart == 0 is possible when wraparound on 16-bit machine */
1610 s->lookahead = (uInt)(s->strstart - max_start);
1611 s->strstart = (uInt)max_start;
1614 /* Flush if we may have to slide, otherwise block_start may become
1615 * negative and the data will be gone:
1617 if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) {
1621 FLUSH_BLOCK(s, flush == Z_FINISH);
1622 return flush == Z_FINISH ? finish_done : block_done;
1625 /* ===========================================================================
1626 * Compress as much as possible from the input stream, return the current
1628 * This function does not perform lazy evaluation of matches and inserts
1629 * new strings in the dictionary only for unmatched strings or for short
1630 * matches. It is used only for the fast compression options.
1632 local block_state deflate_fast(s, flush)
1636 IPos hash_head = NIL; /* head of the hash chain */
1637 int bflush; /* set if current block must be flushed */
1640 /* Make sure that we always have enough lookahead, except
1641 * at the end of the input file. We need MAX_MATCH bytes
1642 * for the next match, plus MIN_MATCH bytes to insert the
1643 * string following the next match.
1645 if (s->lookahead < MIN_LOOKAHEAD) {
1647 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
1650 if (s->lookahead == 0) break; /* flush the current block */
1653 /* Insert the string window[strstart .. strstart+2] in the
1654 * dictionary, and set hash_head to the head of the hash chain:
1656 if (s->lookahead >= MIN_MATCH) {
1657 INSERT_STRING(s, s->strstart, hash_head);
1660 /* Find the longest match, discarding those <= prev_length.
1661 * At this point we have always match_length < MIN_MATCH
1663 if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) {
1664 /* To simplify the code, we prevent matches with the string
1665 * of window index 0 (in particular we have to avoid a match
1666 * of the string with itself at the start of the input file).
1668 if (s->strategy != Z_HUFFMAN_ONLY) {
1669 s->match_length = longest_match (s, hash_head);
1671 /* longest_match() sets match_start */
1673 if (s->match_length >= MIN_MATCH) {
1674 check_match(s, s->strstart, s->match_start, s->match_length);
1676 bflush = _tr_tally(s, s->strstart - s->match_start,
1677 s->match_length - MIN_MATCH);
1679 s->lookahead -= s->match_length;
1681 /* Insert new strings in the hash table only if the match length
1682 * is not too large. This saves time but degrades compression.
1684 if (s->match_length <= s->max_insert_length &&
1685 s->lookahead >= MIN_MATCH) {
1686 s->match_length--; /* string at strstart already in hash table */
1689 INSERT_STRING(s, s->strstart, hash_head);
1690 /* strstart never exceeds WSIZE-MAX_MATCH, so there are
1691 * always MIN_MATCH bytes ahead.
1693 } while (--s->match_length != 0);
1696 s->strstart += s->match_length;
1697 s->match_length = 0;
1698 s->ins_h = s->window[s->strstart];
1699 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
1701 Call UPDATE_HASH() MIN_MATCH-3 more times
1703 /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not
1704 * matter since it will be recomputed at next deflate call.
1708 /* No match, output a literal byte */
1709 Tracevv((stderr,"%c", s->window[s->strstart]));
1710 bflush = _tr_tally (s, 0, s->window[s->strstart]);
1714 if (bflush) FLUSH_BLOCK(s, 0);
1716 FLUSH_BLOCK(s, flush == Z_FINISH);
1717 return flush == Z_FINISH ? finish_done : block_done;
1720 /* ===========================================================================
1721 * Same as above, but achieves better compression. We use a lazy
1722 * evaluation for matches: a match is finally adopted only if there is
1723 * no better match at the next window position.
1725 local block_state deflate_slow(s, flush)
1729 IPos hash_head = NIL; /* head of hash chain */
1730 int bflush; /* set if current block must be flushed */
1732 /* Process the input block. */
1734 /* Make sure that we always have enough lookahead, except
1735 * at the end of the input file. We need MAX_MATCH bytes
1736 * for the next match, plus MIN_MATCH bytes to insert the
1737 * string following the next match.
1739 if (s->lookahead < MIN_LOOKAHEAD) {
1741 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
1744 if (s->lookahead == 0) break; /* flush the current block */
1747 /* Insert the string window[strstart .. strstart+2] in the
1748 * dictionary, and set hash_head to the head of the hash chain:
1750 if (s->lookahead >= MIN_MATCH) {
1751 INSERT_STRING(s, s->strstart, hash_head);
1754 /* Find the longest match, discarding those <= prev_length.
1756 s->prev_length = s->match_length, s->prev_match = s->match_start;
1757 s->match_length = MIN_MATCH-1;
1759 if (hash_head != NIL && s->prev_length < s->max_lazy_match &&
1760 s->strstart - hash_head <= MAX_DIST(s)) {
1761 /* To simplify the code, we prevent matches with the string
1762 * of window index 0 (in particular we have to avoid a match
1763 * of the string with itself at the start of the input file).
1765 if (s->strategy != Z_HUFFMAN_ONLY) {
1766 s->match_length = longest_match (s, hash_head);
1768 /* longest_match() sets match_start */
1770 if (s->match_length <= 5 && (s->strategy == Z_FILTERED ||
1771 (s->match_length == MIN_MATCH &&
1772 s->strstart - s->match_start > TOO_FAR))) {
1774 /* If prev_match is also MIN_MATCH, match_start is garbage
1775 * but we will ignore the current match anyway.
1777 s->match_length = MIN_MATCH-1;
1780 /* If there was a match at the previous step and the current
1781 * match is not better, output the previous match:
1783 if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) {
1784 uInt max_insert = s->strstart + s->lookahead - MIN_MATCH;
1785 /* Do not insert strings in hash table beyond this. */
1787 check_match(s, s->strstart-1, s->prev_match, s->prev_length);
1789 bflush = _tr_tally(s, s->strstart -1 - s->prev_match,
1790 s->prev_length - MIN_MATCH);
1792 /* Insert in hash table all strings up to the end of the match.
1793 * strstart-1 and strstart are already inserted. If there is not
1794 * enough lookahead, the last two strings are not inserted in
1797 s->lookahead -= s->prev_length-1;
1798 s->prev_length -= 2;
1800 if (++s->strstart <= max_insert) {
1801 INSERT_STRING(s, s->strstart, hash_head);
1803 } while (--s->prev_length != 0);
1804 s->match_available = 0;
1805 s->match_length = MIN_MATCH-1;
1808 if (bflush) FLUSH_BLOCK(s, 0);
1810 } else if (s->match_available) {
1811 /* If there was no match at the previous position, output a
1812 * single literal. If there was a match but the current match
1813 * is longer, truncate the previous match to a single literal.
1815 Tracevv((stderr,"%c", s->window[s->strstart-1]));
1816 if (_tr_tally (s, 0, s->window[s->strstart-1])) {
1817 FLUSH_BLOCK_ONLY(s, 0);
1821 if (s->strm->avail_out == 0) return need_more;
1823 /* There is no previous match to compare with, wait for
1824 * the next step to decide.
1826 s->match_available = 1;
1831 Assert (flush != Z_NO_FLUSH, "no flush?");
1832 if (s->match_available) {
1833 Tracevv((stderr,"%c", s->window[s->strstart-1]));
1834 _tr_tally (s, 0, s->window[s->strstart-1]);
1835 s->match_available = 0;
1837 FLUSH_BLOCK(s, flush == Z_FINISH);
1838 return flush == Z_FINISH ? finish_done : block_done;
1843 /* trees.c -- output deflated data using Huffman coding
1844 * Copyright (C) 1995-1996 Jean-loup Gailly
1845 * For conditions of distribution and use, see copyright notice in zlib.h
1851 * The "deflation" process uses several Huffman trees. The more
1852 * common source values are represented by shorter bit sequences.
1854 * Each code tree is stored in a compressed form which is itself
1855 * a Huffman encoding of the lengths of all the code strings (in
1856 * ascending order by source values). The actual code strings are
1857 * reconstructed from the lengths in the inflate process, as described
1858 * in the deflate specification.
1862 * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification".
1863 * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc
1866 * Data Compression: Methods and Theory, pp. 49-50.
1867 * Computer Science Press, 1988. ISBN 0-7167-8156-5.
1871 * Addison-Wesley, 1983. ISBN 0-201-06672-6.
1874 /* From: trees.c,v 1.11 1996/07/24 13:41:06 me Exp $ */
1876 /* #include "deflate.h" */
1882 /* ===========================================================================
1886 #define MAX_BL_BITS 7
1887 /* Bit length codes must not exceed MAX_BL_BITS bits */
1889 #define END_BLOCK 256
1890 /* end of block literal code */
1893 /* repeat previous bit length 3-6 times (2 bits of repeat count) */
1895 #define REPZ_3_10 17
1896 /* repeat a zero length 3-10 times (3 bits of repeat count) */
1898 #define REPZ_11_138 18
1899 /* repeat a zero length 11-138 times (7 bits of repeat count) */
1901 local int extra_lbits[LENGTH_CODES] /* extra bits for each length code */
1902 = {0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0};
1904 local int extra_dbits[D_CODES] /* extra bits for each distance code */
1905 = {0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13};
1907 local int extra_blbits[BL_CODES]/* extra bits for each bit length code */
1908 = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};
1910 local uch bl_order[BL_CODES]
1911 = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};
1912 /* The lengths of the bit length codes are sent in order of decreasing
1913 * probability, to avoid transmitting the lengths for unused bit length codes.
1916 #define Buf_size (8 * 2*sizeof(char))
1917 /* Number of bits used within bi_buf. (bi_buf might be implemented on
1918 * more than 16 bits on some systems.)
1921 /* ===========================================================================
1922 * Local data. These are initialized only once.
1925 local ct_data static_ltree[L_CODES+2];
1926 /* The static literal tree. Since the bit lengths are imposed, there is no
1927 * need for the L_CODES extra codes used during heap construction. However
1928 * The codes 286 and 287 are needed to build a canonical tree (see _tr_init
1932 local ct_data static_dtree[D_CODES];
1933 /* The static distance tree. (Actually a trivial tree since all codes use
1937 local uch dist_code[512];
1938 /* distance codes. The first 256 values correspond to the distances
1939 * 3 .. 258, the last 256 values correspond to the top 8 bits of
1940 * the 15 bit distances.
1943 local uch length_code[MAX_MATCH-MIN_MATCH+1];
1944 /* length code for each normalized match length (0 == MIN_MATCH) */
1946 local int base_length[LENGTH_CODES];
1947 /* First normalized length for each code (0 = MIN_MATCH) */
1949 local int base_dist[D_CODES];
1950 /* First normalized distance for each code (0 = distance of 1) */
1952 struct static_tree_desc_s {
1953 ct_data *static_tree; /* static tree or NULL */
1954 intf *extra_bits; /* extra bits for each code or NULL */
1955 int extra_base; /* base index for extra_bits */
1956 int elems; /* max number of elements in the tree */
1957 int max_length; /* max bit length for the codes */
1960 local static_tree_desc static_l_desc =
1961 {static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS};
1963 local static_tree_desc static_d_desc =
1964 {static_dtree, extra_dbits, 0, D_CODES, MAX_BITS};
1966 local static_tree_desc static_bl_desc =
1967 {(ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS};
1969 /* ===========================================================================
1970 * Local (static) routines in this file.
1973 local void tr_static_init OF((void));
1974 local void init_block OF((deflate_state *s));
1975 local void pqdownheap OF((deflate_state *s, ct_data *tree, int k));
1976 local void gen_bitlen OF((deflate_state *s, tree_desc *desc));
1977 local void gen_codes OF((ct_data *tree, int max_code, ushf *bl_count));
1978 local void build_tree OF((deflate_state *s, tree_desc *desc));
1979 local void scan_tree OF((deflate_state *s, ct_data *tree, int max_code));
1980 local void send_tree OF((deflate_state *s, ct_data *tree, int max_code));
1981 local int build_bl_tree OF((deflate_state *s));
1982 local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes,
1984 local void compress_block OF((deflate_state *s, ct_data *ltree,
1986 local void set_data_type OF((deflate_state *s));
1987 local unsigned bi_reverse OF((unsigned value, int length));
1988 local void bi_windup OF((deflate_state *s));
1989 local void bi_flush OF((deflate_state *s));
1990 local void copy_block OF((deflate_state *s, charf *buf, unsigned len,
1994 # define send_code(s, c, tree) send_bits(s, tree[(c)].Code, tree[(c)].Len)
1995 /* Send a code of the given tree. c and tree must not have side effects */
1997 #else /* DEBUG_ZLIB */
1998 # define send_code(s, c, tree) \
1999 { if (verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \
2000 send_bits(s, tree[c].Code, tree[c].Len); }
2003 #define d_code(dist) \
2004 ((dist) < 256 ? dist_code[dist] : dist_code[256+((dist)>>7)])
2005 /* Mapping from a distance to a distance code. dist is the distance - 1 and
2006 * must not have side effects. dist_code[256] and dist_code[257] are never
2010 /* ===========================================================================
2011 * Output a short LSB first on the stream.
2012 * IN assertion: there is enough room in pendingBuf.
2014 #define put_short(s, w) { \
2015 put_byte(s, (uch)((w) & 0xff)); \
2016 put_byte(s, (uch)((ush)(w) >> 8)); \
2019 /* ===========================================================================
2020 * Send a value on a given number of bits.
2021 * IN assertion: length <= 16 and value fits in length bits.
2024 local void send_bits OF((deflate_state *s, int value, int length));
2026 local void send_bits(s, value, length)
2028 int value; /* value to send */
2029 int length; /* number of bits */
2031 Tracevv((stderr," l %2d v %4x ", length, value));
2032 Assert(length > 0 && length <= 15, "invalid length");
2033 s->bits_sent += (ulg)length;
2035 /* If not enough room in bi_buf, use (valid) bits from bi_buf and
2036 * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
2037 * unused bits in value.
2039 if (s->bi_valid > (int)Buf_size - length) {
2040 s->bi_buf |= (value << s->bi_valid);
2041 put_short(s, s->bi_buf);
2042 s->bi_buf = (ush)value >> (Buf_size - s->bi_valid);
2043 s->bi_valid += length - Buf_size;
2045 s->bi_buf |= value << s->bi_valid;
2046 s->bi_valid += length;
2049 #else /* !DEBUG_ZLIB */
2051 #define send_bits(s, value, length) \
2052 { int len = (length);\
2053 if ((s)->bi_valid > (int)Buf_size - len) {\
2055 (s)->bi_buf |= (val << (s)->bi_valid);\
2056 put_short((s), (s)->bi_buf);\
2057 (s)->bi_buf = (ush)val >> (Buf_size - (s)->bi_valid);\
2058 (s)->bi_valid += len - Buf_size;\
2060 (s)->bi_buf |= (value) << (s)->bi_valid;\
2061 (s)->bi_valid += len;\
2064 #endif /* DEBUG_ZLIB */
2066 /* the arguments must not have side effects */
2068 /* ===========================================================================
2069 * Initialize the various 'constant' tables. In a multi-threaded environment,
2070 * this function may be called by two threads concurrently, but this is
2071 * harmless since both invocations do exactly the same thing.
2073 local void tr_static_init()
2075 static int static_init_done = 0;
2076 int n; /* iterates over tree elements */
2077 int bits; /* bit counter */
2078 int length; /* length value */
2079 int code; /* code value */
2080 int dist; /* distance index */
2081 ush bl_count[MAX_BITS+1];
2082 /* number of codes at each bit length for an optimal tree */
2084 if (static_init_done) return;
2086 /* Initialize the mapping length (0..255) -> length code (0..28) */
2088 for (code = 0; code < LENGTH_CODES-1; code++) {
2089 base_length[code] = length;
2090 for (n = 0; n < (1<<extra_lbits[code]); n++) {
2091 length_code[length++] = (uch)code;
2094 Assert (length == 256, "tr_static_init: length != 256");
2095 /* Note that the length 255 (match length 258) can be represented
2096 * in two different ways: code 284 + 5 bits or code 285, so we
2097 * overwrite length_code[255] to use the best encoding:
2099 length_code[length-1] = (uch)code;
2101 /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
2103 for (code = 0 ; code < 16; code++) {
2104 base_dist[code] = dist;
2105 for (n = 0; n < (1<<extra_dbits[code]); n++) {
2106 dist_code[dist++] = (uch)code;
2109 Assert (dist == 256, "tr_static_init: dist != 256");
2110 dist >>= 7; /* from now on, all distances are divided by 128 */
2111 for ( ; code < D_CODES; code++) {
2112 base_dist[code] = dist << 7;
2113 for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
2114 dist_code[256 + dist++] = (uch)code;
2117 Assert (dist == 256, "tr_static_init: 256+dist != 512");
2119 /* Construct the codes of the static literal tree */
2120 for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
2122 while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;
2123 while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;
2124 while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;
2125 while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;
2126 /* Codes 286 and 287 do not exist, but we must include them in the
2127 * tree construction to get a canonical Huffman tree (longest code
2130 gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count);
2132 /* The static distance tree is trivial: */
2133 for (n = 0; n < D_CODES; n++) {
2134 static_dtree[n].Len = 5;
2135 static_dtree[n].Code = bi_reverse((unsigned)n, 5);
2137 static_init_done = 1;
2140 /* ===========================================================================
2141 * Initialize the tree data structures for a new zlib stream.
2148 s->compressed_len = 0L;
2150 s->l_desc.dyn_tree = s->dyn_ltree;
2151 s->l_desc.stat_desc = &static_l_desc;
2153 s->d_desc.dyn_tree = s->dyn_dtree;
2154 s->d_desc.stat_desc = &static_d_desc;
2156 s->bl_desc.dyn_tree = s->bl_tree;
2157 s->bl_desc.stat_desc = &static_bl_desc;
2161 s->last_eob_len = 8; /* enough lookahead for inflate */
2166 /* Initialize the first block of the first file: */
2170 /* ===========================================================================
2171 * Initialize a new block.
2173 local void init_block(s)
2176 int n; /* iterates over tree elements */
2178 /* Initialize the trees. */
2179 for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0;
2180 for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0;
2181 for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
2183 s->dyn_ltree[END_BLOCK].Freq = 1;
2184 s->opt_len = s->static_len = 0L;
2185 s->last_lit = s->matches = 0;
2189 /* Index within the heap array of least frequent node in the Huffman tree */
2192 /* ===========================================================================
2193 * Remove the smallest element from the heap and recreate the heap with
2194 * one less element. Updates heap and heap_len.
2196 #define pqremove(s, tree, top) \
2198 top = s->heap[SMALLEST]; \
2199 s->heap[SMALLEST] = s->heap[s->heap_len--]; \
2200 pqdownheap(s, tree, SMALLEST); \
2203 /* ===========================================================================
2204 * Compares to subtrees, using the tree depth as tie breaker when
2205 * the subtrees have equal frequency. This minimizes the worst case length.
2207 #define smaller(tree, n, m, depth) \
2208 (tree[n].Freq < tree[m].Freq || \
2209 (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m]))
2211 /* ===========================================================================
2212 * Restore the heap property by moving down the tree starting at node k,
2213 * exchanging a node with the smallest of its two sons if necessary, stopping
2214 * when the heap property is re-established (each father smaller than its
2217 local void pqdownheap(s, tree, k)
2219 ct_data *tree; /* the tree to restore */
2220 int k; /* node to move down */
2223 int j = k << 1; /* left son of k */
2224 while (j <= s->heap_len) {
2225 /* Set j to the smallest of the two sons: */
2226 if (j < s->heap_len &&
2227 smaller(tree, s->heap[j+1], s->heap[j], s->depth)) {
2230 /* Exit if v is smaller than both sons */
2231 if (smaller(tree, v, s->heap[j], s->depth)) break;
2233 /* Exchange v with the smallest son */
2234 s->heap[k] = s->heap[j]; k = j;
2236 /* And continue down the tree, setting j to the left son of k */
2242 /* ===========================================================================
2243 * Compute the optimal bit lengths for a tree and update the total bit length
2244 * for the current block.
2245 * IN assertion: the fields freq and dad are set, heap[heap_max] and
2246 * above are the tree nodes sorted by increasing frequency.
2247 * OUT assertions: the field len is set to the optimal bit length, the
2248 * array bl_count contains the frequencies for each bit length.
2249 * The length opt_len is updated; static_len is also updated if stree is
2252 local void gen_bitlen(s, desc)
2254 tree_desc *desc; /* the tree descriptor */
2256 ct_data *tree = desc->dyn_tree;
2257 int max_code = desc->max_code;
2258 ct_data *stree = desc->stat_desc->static_tree;
2259 intf *extra = desc->stat_desc->extra_bits;
2260 int base = desc->stat_desc->extra_base;
2261 int max_length = desc->stat_desc->max_length;
2262 int h; /* heap index */
2263 int n, m; /* iterate over the tree elements */
2264 int bits; /* bit length */
2265 int xbits; /* extra bits */
2266 ush f; /* frequency */
2267 int overflow = 0; /* number of elements with bit length too large */
2269 for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0;
2271 /* In a first pass, compute the optimal bit lengths (which may
2272 * overflow in the case of the bit length tree).
2274 tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */
2276 for (h = s->heap_max+1; h < HEAP_SIZE; h++) {
2278 bits = tree[tree[n].Dad].Len + 1;
2279 if (bits > max_length) bits = max_length, overflow++;
2280 tree[n].Len = (ush)bits;
2281 /* We overwrite tree[n].Dad which is no longer needed */
2283 if (n > max_code) continue; /* not a leaf node */
2285 s->bl_count[bits]++;
2287 if (n >= base) xbits = extra[n-base];
2289 s->opt_len += (ulg)f * (bits + xbits);
2290 if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits);
2292 if (overflow == 0) return;
2294 Trace((stderr,"\nbit length overflow\n"));
2295 /* This happens for example on obj2 and pic of the Calgary corpus */
2297 /* Find the first bit length which could increase: */
2299 bits = max_length-1;
2300 while (s->bl_count[bits] == 0) bits--;
2301 s->bl_count[bits]--; /* move one leaf down the tree */
2302 s->bl_count[bits+1] += 2; /* move one overflow item as its brother */
2303 s->bl_count[max_length]--;
2304 /* The brother of the overflow item also moves one step up,
2305 * but this does not affect bl_count[max_length]
2308 } while (overflow > 0);
2310 /* Now recompute all bit lengths, scanning in increasing frequency.
2311 * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
2312 * lengths instead of fixing only the wrong ones. This idea is taken
2313 * from 'ar' written by Haruhiko Okumura.)
2315 for (bits = max_length; bits != 0; bits--) {
2316 n = s->bl_count[bits];
2319 if (m > max_code) continue;
2320 if (tree[m].Len != (unsigned) bits) {
2321 Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits));
2322 s->opt_len += ((long)bits - (long)tree[m].Len)
2323 *(long)tree[m].Freq;
2324 tree[m].Len = (ush)bits;
2331 /* ===========================================================================
2332 * Generate the codes for a given tree and bit counts (which need not be
2334 * IN assertion: the array bl_count contains the bit length statistics for
2335 * the given tree and the field len is set for all tree elements.
2336 * OUT assertion: the field code is set for all tree elements of non
2339 local void gen_codes (tree, max_code, bl_count)
2340 ct_data *tree; /* the tree to decorate */
2341 int max_code; /* largest code with non zero frequency */
2342 ushf *bl_count; /* number of codes at each bit length */
2344 ush next_code[MAX_BITS+1]; /* next code value for each bit length */
2345 ush code = 0; /* running code value */
2346 int bits; /* bit index */
2347 int n; /* code index */
2349 /* The distribution counts are first used to generate the code values
2350 * without bit reversal.
2352 for (bits = 1; bits <= MAX_BITS; bits++) {
2353 next_code[bits] = code = (code + bl_count[bits-1]) << 1;
2355 /* Check that the bit counts in bl_count are consistent. The last code
2358 Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
2359 "inconsistent bit counts");
2360 Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
2362 for (n = 0; n <= max_code; n++) {
2363 int len = tree[n].Len;
2364 if (len == 0) continue;
2365 /* Now reverse the bits */
2366 tree[n].Code = bi_reverse(next_code[len]++, len);
2368 Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
2369 n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
2373 /* ===========================================================================
2374 * Construct one Huffman tree and assigns the code bit strings and lengths.
2375 * Update the total bit length for the current block.
2376 * IN assertion: the field freq is set for all tree elements.
2377 * OUT assertions: the fields len and code are set to the optimal bit length
2378 * and corresponding code. The length opt_len is updated; static_len is
2379 * also updated if stree is not null. The field max_code is set.
2381 local void build_tree(s, desc)
2383 tree_desc *desc; /* the tree descriptor */
2385 ct_data *tree = desc->dyn_tree;
2386 ct_data *stree = desc->stat_desc->static_tree;
2387 int elems = desc->stat_desc->elems;
2388 int n, m; /* iterate over heap elements */
2389 int max_code = -1; /* largest code with non zero frequency */
2390 int node; /* new node being created */
2392 /* Construct the initial heap, with least frequent element in
2393 * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
2394 * heap[0] is not used.
2396 s->heap_len = 0, s->heap_max = HEAP_SIZE;
2398 for (n = 0; n < elems; n++) {
2399 if (tree[n].Freq != 0) {
2400 s->heap[++(s->heap_len)] = max_code = n;
2407 /* The pkzip format requires that at least one distance code exists,
2408 * and that at least one bit should be sent even if there is only one
2409 * possible code. So to avoid special checks later on we force at least
2410 * two codes of non zero frequency.
2412 while (s->heap_len < 2) {
2413 node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0);
2414 tree[node].Freq = 1;
2416 s->opt_len--; if (stree) s->static_len -= stree[node].Len;
2417 /* node is 0 or 1 so it does not have extra bits */
2419 desc->max_code = max_code;
2421 /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
2422 * establish sub-heaps of increasing lengths:
2424 for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n);
2426 /* Construct the Huffman tree by repeatedly combining the least two
2429 node = elems; /* next internal node of the tree */
2431 pqremove(s, tree, n); /* n = node of least frequency */
2432 m = s->heap[SMALLEST]; /* m = node of next least frequency */
2434 s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */
2435 s->heap[--(s->heap_max)] = m;
2437 /* Create a new node father of n and m */
2438 tree[node].Freq = tree[n].Freq + tree[m].Freq;
2439 s->depth[node] = (uch) (MAX(s->depth[n], s->depth[m]) + 1);
2440 tree[n].Dad = tree[m].Dad = (ush)node;
2442 if (tree == s->bl_tree) {
2443 fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)",
2444 node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq);
2447 /* and insert the new node in the heap */
2448 s->heap[SMALLEST] = node++;
2449 pqdownheap(s, tree, SMALLEST);
2451 } while (s->heap_len >= 2);
2453 s->heap[--(s->heap_max)] = s->heap[SMALLEST];
2455 /* At this point, the fields freq and dad are set. We can now
2456 * generate the bit lengths.
2458 gen_bitlen(s, (tree_desc *)desc);
2460 /* The field len is now set, we can generate the bit codes */
2461 gen_codes ((ct_data *)tree, max_code, s->bl_count);
2464 /* ===========================================================================
2465 * Scan a literal or distance tree to determine the frequencies of the codes
2466 * in the bit length tree.
2468 local void scan_tree (s, tree, max_code)
2470 ct_data *tree; /* the tree to be scanned */
2471 int max_code; /* and its largest code of non zero frequency */
2473 int n; /* iterates over all tree elements */
2474 int prevlen = -1; /* last emitted length */
2475 int curlen; /* length of current code */
2476 int nextlen = tree[0].Len; /* length of next code */
2477 int count = 0; /* repeat count of the current code */
2478 int max_count = 7; /* max repeat count */
2479 int min_count = 4; /* min repeat count */
2481 if (nextlen == 0) max_count = 138, min_count = 3;
2482 tree[max_code+1].Len = (ush)0xffff; /* guard */
2484 for (n = 0; n <= max_code; n++) {
2485 curlen = nextlen; nextlen = tree[n+1].Len;
2486 if (++count < max_count && curlen == nextlen) {
2488 } else if (count < min_count) {
2489 s->bl_tree[curlen].Freq += count;
2490 } else if (curlen != 0) {
2491 if (curlen != prevlen) s->bl_tree[curlen].Freq++;
2492 s->bl_tree[REP_3_6].Freq++;
2493 } else if (count <= 10) {
2494 s->bl_tree[REPZ_3_10].Freq++;
2496 s->bl_tree[REPZ_11_138].Freq++;
2498 count = 0; prevlen = curlen;
2500 max_count = 138, min_count = 3;
2501 } else if (curlen == nextlen) {
2502 max_count = 6, min_count = 3;
2504 max_count = 7, min_count = 4;
2509 /* ===========================================================================
2510 * Send a literal or distance tree in compressed form, using the codes in
2513 local void send_tree (s, tree, max_code)
2515 ct_data *tree; /* the tree to be scanned */
2516 int max_code; /* and its largest code of non zero frequency */
2518 int n; /* iterates over all tree elements */
2519 int prevlen = -1; /* last emitted length */
2520 int curlen; /* length of current code */
2521 int nextlen = tree[0].Len; /* length of next code */
2522 int count = 0; /* repeat count of the current code */
2523 int max_count = 7; /* max repeat count */
2524 int min_count = 4; /* min repeat count */
2526 /* tree[max_code+1].Len = -1; */ /* guard already set */
2527 if (nextlen == 0) max_count = 138, min_count = 3;
2529 for (n = 0; n <= max_code; n++) {
2530 curlen = nextlen; nextlen = tree[n+1].Len;
2531 if (++count < max_count && curlen == nextlen) {
2533 } else if (count < min_count) {
2534 do { send_code(s, curlen, s->bl_tree); } while (--count != 0);
2536 } else if (curlen != 0) {
2537 if (curlen != prevlen) {
2538 send_code(s, curlen, s->bl_tree); count--;
2540 Assert(count >= 3 && count <= 6, " 3_6?");
2541 send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2);
2543 } else if (count <= 10) {
2544 send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3);
2547 send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7);
2549 count = 0; prevlen = curlen;
2551 max_count = 138, min_count = 3;
2552 } else if (curlen == nextlen) {
2553 max_count = 6, min_count = 3;
2555 max_count = 7, min_count = 4;
2560 /* ===========================================================================
2561 * Construct the Huffman tree for the bit lengths and return the index in
2562 * bl_order of the last bit length code to send.
2564 local int build_bl_tree(s)
2567 int max_blindex; /* index of last bit length code of non zero freq */
2569 /* Determine the bit length frequencies for literal and distance trees */
2570 scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code);
2571 scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code);
2573 /* Build the bit length tree: */
2574 build_tree(s, (tree_desc *)(&(s->bl_desc)));
2575 /* opt_len now includes the length of the tree representations, except
2576 * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
2579 /* Determine the number of bit length codes to send. The pkzip format
2580 * requires that at least 4 bit length codes be sent. (appnote.txt says
2581 * 3 but the actual value used is 4.)
2583 for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) {
2584 if (s->bl_tree[bl_order[max_blindex]].Len != 0) break;
2586 /* Update opt_len to include the bit length tree and counts */
2587 s->opt_len += 3*(max_blindex+1) + 5+5+4;
2588 Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
2589 s->opt_len, s->static_len));
2594 /* ===========================================================================
2595 * Send the header for a block using dynamic Huffman trees: the counts, the
2596 * lengths of the bit length codes, the literal tree and the distance tree.
2597 * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
2599 local void send_all_trees(s, lcodes, dcodes, blcodes)
2601 int lcodes, dcodes, blcodes; /* number of codes for each tree */
2603 int rank; /* index in bl_order */
2605 Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
2606 Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
2608 Tracev((stderr, "\nbl counts: "));
2609 send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */
2610 send_bits(s, dcodes-1, 5);
2611 send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */
2612 for (rank = 0; rank < blcodes; rank++) {
2613 Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
2614 send_bits(s, s->bl_tree[bl_order[rank]].Len, 3);
2616 Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent));
2618 send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */
2619 Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent));
2621 send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */
2622 Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent));
2625 /* ===========================================================================
2626 * Send a stored block
2628 void _tr_stored_block(s, buf, stored_len, eof)
2630 charf *buf; /* input block */
2631 ulg stored_len; /* length of input block */
2632 int eof; /* true if this is the last block for a file */
2634 send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */
2635 s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
2636 s->compressed_len += (stored_len + 4) << 3;
2638 copy_block(s, buf, (unsigned)stored_len, 1); /* with header */
2641 /* Send just the `stored block' type code without any length bytes or data.
2643 void _tr_stored_type_only(s)
2646 send_bits(s, (STORED_BLOCK << 1), 3);
2648 s->compressed_len = (s->compressed_len + 3) & ~7L;
2652 /* ===========================================================================
2653 * Send one empty static block to give enough lookahead for inflate.
2654 * This takes 10 bits, of which 7 may remain in the bit buffer.
2655 * The current inflate code requires 9 bits of lookahead. If the
2656 * last two codes for the previous block (real code plus EOB) were coded
2657 * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode
2658 * the last real code. In this case we send two empty static blocks instead
2659 * of one. (There are no problems if the previous block is stored or fixed.)
2660 * To simplify the code, we assume the worst case of last real code encoded
2666 send_bits(s, STATIC_TREES<<1, 3);
2667 send_code(s, END_BLOCK, static_ltree);
2668 s->compressed_len += 10L; /* 3 for block type, 7 for EOB */
2670 /* Of the 10 bits for the empty block, we have already sent
2671 * (10 - bi_valid) bits. The lookahead for the last real code (before
2672 * the EOB of the previous block) was thus at least one plus the length
2673 * of the EOB plus what we have just sent of the empty static block.
2675 if (1 + s->last_eob_len + 10 - s->bi_valid < 9) {
2676 send_bits(s, STATIC_TREES<<1, 3);
2677 send_code(s, END_BLOCK, static_ltree);
2678 s->compressed_len += 10L;
2681 s->last_eob_len = 7;
2684 /* ===========================================================================
2685 * Determine the best encoding for the current block: dynamic trees, static
2686 * trees or store, and output the encoded block to the zip file. This function
2687 * returns the total compressed length for the file so far.
2689 ulg _tr_flush_block(s, buf, stored_len, eof)
2691 charf *buf; /* input block, or NULL if too old */
2692 ulg stored_len; /* length of input block */
2693 int eof; /* true if this is the last block for a file */
2695 ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
2696 int max_blindex = 0; /* index of last bit length code of non zero freq */
2698 /* Build the Huffman trees unless a stored block is forced */
2701 /* Check if the file is ascii or binary */
2702 if (s->data_type == Z_UNKNOWN) set_data_type(s);
2704 /* Construct the literal and distance trees */
2705 build_tree(s, (tree_desc *)(&(s->l_desc)));
2706 Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len,
2709 build_tree(s, (tree_desc *)(&(s->d_desc)));
2710 Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len,
2712 /* At this point, opt_len and static_len are the total bit lengths of
2713 * the compressed block data, excluding the tree representations.
2716 /* Build the bit length tree for the above two trees, and get the index
2717 * in bl_order of the last bit length code to send.
2719 max_blindex = build_bl_tree(s);
2721 /* Determine the best encoding. Compute first the block length in bytes*/
2722 opt_lenb = (s->opt_len+3+7)>>3;
2723 static_lenb = (s->static_len+3+7)>>3;
2725 Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
2726 opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
2729 if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
2732 Assert(buf != (char*)0, "lost buf");
2733 opt_lenb = static_lenb = stored_len + 5; /* force a stored block */
2736 /* If compression failed and this is the first and last block,
2737 * and if the .zip file can be seeked (to rewrite the local header),
2738 * the whole file is transformed into a stored file:
2740 #ifdef STORED_FILE_OK
2741 # ifdef FORCE_STORED_FILE
2742 if (eof && s->compressed_len == 0L) { /* force stored file */
2744 if (stored_len <= opt_lenb && eof && s->compressed_len==0L && seekable()) {
2746 /* Since LIT_BUFSIZE <= 2*WSIZE, the input data must be there: */
2747 if (buf == (charf*)0) error ("block vanished");
2749 copy_block(s, buf, (unsigned)stored_len, 0); /* without header */
2750 s->compressed_len = stored_len << 3;
2753 #endif /* STORED_FILE_OK */
2756 if (buf != (char*)0) { /* force stored block */
2758 if (stored_len+4 <= opt_lenb && buf != (char*)0) {
2759 /* 4: two words for the lengths */
2761 /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
2762 * Otherwise we can't have processed more than WSIZE input bytes since
2763 * the last block flush, because compression would have been
2764 * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
2765 * transform a block into a stored block.
2767 _tr_stored_block(s, buf, stored_len, eof);
2770 } else if (static_lenb >= 0) { /* force static trees */
2772 } else if (static_lenb == opt_lenb) {
2774 send_bits(s, (STATIC_TREES<<1)+eof, 3);
2775 compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree);
2776 s->compressed_len += 3 + s->static_len;
2778 send_bits(s, (DYN_TREES<<1)+eof, 3);
2779 send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
2781 compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree);
2782 s->compressed_len += 3 + s->opt_len;
2784 Assert (s->compressed_len == s->bits_sent, "bad compressed size");
2789 s->compressed_len += 7; /* align on byte boundary */
2791 Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
2792 s->compressed_len-7*eof));
2794 return s->compressed_len >> 3;
2797 /* ===========================================================================
2798 * Save the match info and tally the frequency counts. Return true if
2799 * the current block must be flushed.
2801 int _tr_tally (s, dist, lc)
2803 unsigned dist; /* distance of matched string */
2804 unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */
2806 s->d_buf[s->last_lit] = (ush)dist;
2807 s->l_buf[s->last_lit++] = (uch)lc;
2809 /* lc is the unmatched char */
2810 s->dyn_ltree[lc].Freq++;
2813 /* Here, lc is the match length - MIN_MATCH */
2814 dist--; /* dist = match distance - 1 */
2815 Assert((ush)dist < (ush)MAX_DIST(s) &&
2816 (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
2817 (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match");
2819 s->dyn_ltree[length_code[lc]+LITERALS+1].Freq++;
2820 s->dyn_dtree[d_code(dist)].Freq++;
2823 /* Try to guess if it is profitable to stop the current block here */
2824 if (s->level > 2 && (s->last_lit & 0xfff) == 0) {
2825 /* Compute an upper bound for the compressed length */
2826 ulg out_length = (ulg)s->last_lit*8L;
2827 ulg in_length = (ulg)((long)s->strstart - s->block_start);
2829 for (dcode = 0; dcode < D_CODES; dcode++) {
2830 out_length += (ulg)s->dyn_dtree[dcode].Freq *
2831 (5L+extra_dbits[dcode]);
2834 Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ",
2835 s->last_lit, in_length, out_length,
2836 100L - out_length*100L/in_length));
2837 if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1;
2839 return (s->last_lit == s->lit_bufsize-1);
2840 /* We avoid equality with lit_bufsize because of wraparound at 64K
2841 * on 16 bit machines and because stored blocks are restricted to
2846 /* ===========================================================================
2847 * Send the block data compressed using the given Huffman trees
2849 local void compress_block(s, ltree, dtree)
2851 ct_data *ltree; /* literal tree */
2852 ct_data *dtree; /* distance tree */
2854 unsigned dist; /* distance of matched string */
2855 int lc; /* match length or unmatched char (if dist == 0) */
2856 unsigned lx = 0; /* running index in l_buf */
2857 unsigned code; /* the code to send */
2858 int extra; /* number of extra bits to send */
2860 if (s->last_lit != 0) do {
2861 dist = s->d_buf[lx];
2862 lc = s->l_buf[lx++];
2864 send_code(s, lc, ltree); /* send a literal byte */
2865 Tracecv(isgraph(lc), (stderr," '%c' ", lc));
2867 /* Here, lc is the match length - MIN_MATCH */
2868 code = length_code[lc];
2869 send_code(s, code+LITERALS+1, ltree); /* send the length code */
2870 extra = extra_lbits[code];
2872 lc -= base_length[code];
2873 send_bits(s, lc, extra); /* send the extra length bits */
2875 dist--; /* dist is now the match distance - 1 */
2876 code = d_code(dist);
2877 Assert (code < D_CODES, "bad d_code");
2879 send_code(s, code, dtree); /* send the distance code */
2880 extra = extra_dbits[code];
2882 dist -= base_dist[code];
2883 send_bits(s, dist, extra); /* send the extra distance bits */
2885 } /* literal or match pair ? */
2887 /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */
2888 Assert(s->pending < s->lit_bufsize + 2*lx, "pendingBuf overflow");
2890 } while (lx < s->last_lit);
2892 send_code(s, END_BLOCK, ltree);
2893 s->last_eob_len = ltree[END_BLOCK].Len;
2896 /* ===========================================================================
2897 * Set the data type to ASCII or BINARY, using a crude approximation:
2898 * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise.
2899 * IN assertion: the fields freq of dyn_ltree are set and the total of all
2900 * frequencies does not exceed 64K (to fit in an int on 16 bit machines).
2902 local void set_data_type(s)
2906 unsigned ascii_freq = 0;
2907 unsigned bin_freq = 0;
2908 while (n < 7) bin_freq += s->dyn_ltree[n++].Freq;
2909 while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq;
2910 while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq;
2911 s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? Z_BINARY : Z_ASCII);
2914 /* ===========================================================================
2915 * Reverse the first len bits of a code, using straightforward code (a faster
2916 * method would use a table)
2917 * IN assertion: 1 <= len <= 15
2919 local unsigned bi_reverse(code, len)
2920 unsigned code; /* the value to invert */
2921 int len; /* its bit length */
2926 code >>= 1, res <<= 1;
2927 } while (--len > 0);
2931 /* ===========================================================================
2932 * Flush the bit buffer, keeping at most 7 bits in it.
2934 local void bi_flush(s)
2937 if (s->bi_valid == 16) {
2938 put_short(s, s->bi_buf);
2941 } else if (s->bi_valid >= 8) {
2942 put_byte(s, (Byte)s->bi_buf);
2948 /* ===========================================================================
2949 * Flush the bit buffer and align the output on a byte boundary
2951 local void bi_windup(s)
2954 if (s->bi_valid > 8) {
2955 put_short(s, s->bi_buf);
2956 } else if (s->bi_valid > 0) {
2957 put_byte(s, (Byte)s->bi_buf);
2962 s->bits_sent = (s->bits_sent+7) & ~7;
2966 /* ===========================================================================
2967 * Copy a stored block, storing first the length and its
2968 * one's complement if requested.
2970 local void copy_block(s, buf, len, header)
2972 charf *buf; /* the input data */
2973 unsigned len; /* its length */
2974 int header; /* true if block header must be written */
2976 bi_windup(s); /* align on byte boundary */
2977 s->last_eob_len = 8; /* enough lookahead for inflate */
2980 put_short(s, (ush)len);
2981 put_short(s, (ush)~len);
2983 s->bits_sent += 2*16;
2987 s->bits_sent += (ulg)len<<3;
2989 /* bundle up the put_byte(s, *buf++) calls */
2990 zmemcpy(&s->pending_buf[s->pending], buf, len);
2996 /* inflate.c -- zlib interface to inflate modules
2997 * Copyright (C) 1995-1996 Mark Adler
2998 * For conditions of distribution and use, see copyright notice in zlib.h
3001 /* #include "zutil.h" */
3003 /* +++ infblock.h */
3004 /* infblock.h -- header to use infblock.c
3005 * Copyright (C) 1995-1996 Mark Adler
3006 * For conditions of distribution and use, see copyright notice in zlib.h
3009 /* WARNING: this file should *not* be used by applications. It is
3010 part of the implementation of the compression library and is
3011 subject to change. Applications should only use zlib.h.
3014 struct inflate_blocks_state;
3015 typedef struct inflate_blocks_state FAR inflate_blocks_statef;
3017 extern inflate_blocks_statef * inflate_blocks_new OF((
3019 check_func c, /* check function */
3020 uInt w)); /* window size */
3022 extern int inflate_blocks OF((
3023 inflate_blocks_statef *,
3025 int)); /* initial return code */
3027 extern void inflate_blocks_reset OF((
3028 inflate_blocks_statef *,
3030 uLongf *)); /* check value on output */
3032 extern int inflate_blocks_free OF((
3033 inflate_blocks_statef *,
3035 uLongf *)); /* check value on output */
3037 extern void inflate_set_dictionary OF((
3038 inflate_blocks_statef *s,
3039 const Bytef *d, /* dictionary */
3040 uInt n)); /* dictionary length */
3042 extern int inflate_addhistory OF((
3043 inflate_blocks_statef *,
3046 extern int inflate_packet_flush OF((
3047 inflate_blocks_statef *));
3048 /* --- infblock.h */
3050 #ifndef NO_DUMMY_DECL
3051 struct inflate_blocks_state {int dummy;}; /* for buggy compilers */
3054 /* inflate private state */
3055 struct internal_state {
3059 METHOD, /* waiting for method byte */
3060 FLAG, /* waiting for flag byte */
3061 DICT4, /* four dictionary check bytes to go */
3062 DICT3, /* three dictionary check bytes to go */
3063 DICT2, /* two dictionary check bytes to go */
3064 DICT1, /* one dictionary check byte to go */
3065 DICT0, /* waiting for inflateSetDictionary */
3066 BLOCKS, /* decompressing blocks */
3067 CHECK4, /* four check bytes to go */
3068 CHECK3, /* three check bytes to go */
3069 CHECK2, /* two check bytes to go */
3070 CHECK1, /* one check byte to go */
3071 DONE, /* finished check, done */
3072 BAD} /* got an error--stay here */
3073 mode; /* current inflate mode */
3075 /* mode dependent information */
3077 uInt method; /* if FLAGS, method byte */
3079 uLong was; /* computed check value */
3080 uLong need; /* stream check value */
3081 } check; /* if CHECK, check values to compare */
3082 uInt marker; /* if BAD, inflateSync's marker bytes count */
3083 } sub; /* submode */
3085 /* mode independent information */
3086 int nowrap; /* flag for no wrapper */
3087 uInt wbits; /* log2(window size) (8..15, defaults to 15) */
3088 inflate_blocks_statef
3089 *blocks; /* current inflate_blocks state */
3099 if (z == Z_NULL || z->state == Z_NULL)
3100 return Z_STREAM_ERROR;
3101 z->total_in = z->total_out = 0;
3103 z->state->mode = z->state->nowrap ? BLOCKS : METHOD;
3104 inflate_blocks_reset(z->state->blocks, z, &c);
3105 Trace((stderr, "inflate: reset\n"));
3115 if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL)
3116 return Z_STREAM_ERROR;
3117 if (z->state->blocks != Z_NULL)
3118 inflate_blocks_free(z->state->blocks, z, &c);
3121 Trace((stderr, "inflate: end\n"));
3126 int inflateInit2_(z, w, version, stream_size)
3129 const char *version;
3132 if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
3133 stream_size != sizeof(z_stream))
3134 return Z_VERSION_ERROR;
3136 /* initialize state */
3138 return Z_STREAM_ERROR;
3141 if (z->zalloc == Z_NULL)
3143 z->zalloc = zcalloc;
3144 z->opaque = (voidpf)0;
3146 if (z->zfree == Z_NULL) z->zfree = zcfree;
3148 if ((z->state = (struct internal_state FAR *)
3149 ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL)
3151 z->state->blocks = Z_NULL;
3153 /* handle undocumented nowrap option (no zlib header or check) */
3154 z->state->nowrap = 0;
3158 z->state->nowrap = 1;
3161 /* set window size */
3162 if (w < 8 || w > 15)
3165 return Z_STREAM_ERROR;
3167 z->state->wbits = (uInt)w;
3169 /* create inflate_blocks state */
3170 if ((z->state->blocks =
3171 inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, (uInt)1 << w))
3177 Trace((stderr, "inflate: allocated\n"));
3185 int inflateInit_(z, version, stream_size)
3187 const char *version;
3190 return inflateInit2_(z, DEF_WBITS, version, stream_size);
3194 #define NEEDBYTE {if(z->avail_in==0)goto empty;r=Z_OK;}
3195 #define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
3204 if (z == Z_NULL || z->state == Z_NULL || z->next_in == Z_NULL || f < 0)
3205 return Z_STREAM_ERROR;
3207 while (1) switch (z->state->mode)
3211 if (((z->state->sub.method = NEXTBYTE) & 0xf) != Z_DEFLATED)
3213 z->state->mode = BAD;
3214 z->msg = (char*)"unknown compression method";
3215 z->state->sub.marker = 5; /* can't try inflateSync */
3218 if ((z->state->sub.method >> 4) + 8 > z->state->wbits)
3220 z->state->mode = BAD;
3221 z->msg = (char*)"invalid window size";
3222 z->state->sub.marker = 5; /* can't try inflateSync */
3225 z->state->mode = FLAG;
3229 if (((z->state->sub.method << 8) + b) % 31)
3231 z->state->mode = BAD;
3232 z->msg = (char*)"incorrect header check";
3233 z->state->sub.marker = 5; /* can't try inflateSync */
3236 Trace((stderr, "inflate: zlib header ok\n"));
3237 if (!(b & PRESET_DICT))
3239 z->state->mode = BLOCKS;
3242 z->state->mode = DICT4;
3245 z->state->sub.check.need = (uLong)NEXTBYTE << 24;
3246 z->state->mode = DICT3;
3249 z->state->sub.check.need += (uLong)NEXTBYTE << 16;
3250 z->state->mode = DICT2;
3253 z->state->sub.check.need += (uLong)NEXTBYTE << 8;
3254 z->state->mode = DICT1;
3257 z->state->sub.check.need += (uLong)NEXTBYTE;
3258 z->adler = z->state->sub.check.need;
3259 z->state->mode = DICT0;
3262 z->state->mode = BAD;
3263 z->msg = (char*)"need dictionary";
3264 z->state->sub.marker = 0; /* can try inflateSync */
3265 return Z_STREAM_ERROR;
3267 r = inflate_blocks(z->state->blocks, z, r);
3268 if (f == Z_PACKET_FLUSH && z->avail_in == 0 && z->avail_out != 0)
3269 r = inflate_packet_flush(z->state->blocks);
3270 if (r == Z_DATA_ERROR)
3272 z->state->mode = BAD;
3273 z->state->sub.marker = 0; /* can try inflateSync */
3276 if (r != Z_STREAM_END)
3279 inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was);
3280 if (z->state->nowrap)
3282 z->state->mode = DONE;
3285 z->state->mode = CHECK4;
3288 z->state->sub.check.need = (uLong)NEXTBYTE << 24;
3289 z->state->mode = CHECK3;
3292 z->state->sub.check.need += (uLong)NEXTBYTE << 16;
3293 z->state->mode = CHECK2;
3296 z->state->sub.check.need += (uLong)NEXTBYTE << 8;
3297 z->state->mode = CHECK1;
3300 z->state->sub.check.need += (uLong)NEXTBYTE;
3302 if (z->state->sub.check.was != z->state->sub.check.need)
3304 z->state->mode = BAD;
3305 z->msg = (char*)"incorrect data check";
3306 z->state->sub.marker = 5; /* can't try inflateSync */
3309 Trace((stderr, "inflate: zlib check ok\n"));
3310 z->state->mode = DONE;
3312 return Z_STREAM_END;
3314 return Z_DATA_ERROR;
3316 return Z_STREAM_ERROR;
3320 if (f != Z_PACKET_FLUSH)
3322 z->state->mode = BAD;
3323 z->msg = (char *)"need more for packet flush";
3324 z->state->sub.marker = 0; /* can try inflateSync */
3325 return Z_DATA_ERROR;
3329 int inflateSetDictionary(z, dictionary, dictLength)
3331 const Bytef *dictionary;
3334 uInt length = dictLength;
3336 if (z == Z_NULL || z->state == Z_NULL || z->state->mode != DICT0)
3337 return Z_STREAM_ERROR;
3339 if (adler32(1L, dictionary, dictLength) != z->adler) return Z_DATA_ERROR;
3342 if (length >= ((uInt)1<<z->state->wbits))
3344 length = (1<<z->state->wbits)-1;
3345 dictionary += dictLength - length;
3347 inflate_set_dictionary(z->state->blocks, dictionary, length);
3348 z->state->mode = BLOCKS;
3353 * This subroutine adds the data at next_in/avail_in to the output history
3354 * without performing any output. The output buffer must be "caught up";
3355 * i.e. no pending output (hence s->read equals s->write), and the state must
3356 * be BLOCKS (i.e. we should be willing to see the start of a series of
3357 * BLOCKS). On exit, the output will also be caught up, and the checksum
3358 * will have been updated if need be.
3361 int inflateIncomp(z)
3364 if (z->state->mode != BLOCKS)
3365 return Z_DATA_ERROR;
3366 return inflate_addhistory(z->state->blocks, z);
3373 uInt n; /* number of bytes to look at */
3374 Bytef *p; /* pointer to bytes */
3375 uInt m; /* number of marker bytes found in a row */
3376 uLong r, w; /* temporaries to save total_in and total_out */
3379 if (z == Z_NULL || z->state == Z_NULL)
3380 return Z_STREAM_ERROR;
3381 if (z->state->mode != BAD)
3383 z->state->mode = BAD;
3384 z->state->sub.marker = 0;
3386 if ((n = z->avail_in) == 0)
3389 m = z->state->sub.marker;
3394 if (*p == (Byte)(m < 2 ? 0 : 0xff))
3404 z->total_in += p - z->next_in;
3407 z->state->sub.marker = m;
3409 /* return no joy or set up to restart on a new block */
3411 return Z_DATA_ERROR;
3412 r = z->total_in; w = z->total_out;
3414 z->total_in = r; z->total_out = w;
3415 z->state->mode = BLOCKS;
3423 /* +++ infblock.c */
3424 /* infblock.c -- interpret and process block types to last block
3425 * Copyright (C) 1995-1996 Mark Adler
3426 * For conditions of distribution and use, see copyright notice in zlib.h
3429 /* #include "zutil.h" */
3430 /* #include "infblock.h" */
3432 /* +++ inftrees.h */
3433 /* inftrees.h -- header to use inftrees.c
3434 * Copyright (C) 1995-1996 Mark Adler
3435 * For conditions of distribution and use, see copyright notice in zlib.h
3438 /* WARNING: this file should *not* be used by applications. It is
3439 part of the implementation of the compression library and is
3440 subject to change. Applications should only use zlib.h.
3443 /* Huffman code lookup table entry--this entry is four bytes for machines
3444 that have 16-bit pointers (e.g. PC's in the small or medium model). */
3446 typedef struct inflate_huft_s FAR inflate_huft;
3448 struct inflate_huft_s {
3451 Byte Exop; /* number of extra bits or operation */
3452 Byte Bits; /* number of bits in this code or subcode */
3454 Bytef *pad; /* pad structure to a power of 2 (4 bytes for */
3455 } word; /* 16-bit, 8 bytes for 32-bit machines) */
3457 uInt Base; /* literal, length base, or distance base */
3458 inflate_huft *Next; /* pointer to next level of table */
3463 extern uInt inflate_hufts;
3466 extern int inflate_trees_bits OF((
3467 uIntf *, /* 19 code lengths */
3468 uIntf *, /* bits tree desired/actual depth */
3469 inflate_huft * FAR *, /* bits tree result */
3470 z_streamp )); /* for zalloc, zfree functions */
3472 extern int inflate_trees_dynamic OF((
3473 uInt, /* number of literal/length codes */
3474 uInt, /* number of distance codes */
3475 uIntf *, /* that many (total) code lengths */
3476 uIntf *, /* literal desired/actual bit depth */
3477 uIntf *, /* distance desired/actual bit depth */
3478 inflate_huft * FAR *, /* literal/length tree result */
3479 inflate_huft * FAR *, /* distance tree result */
3480 z_streamp )); /* for zalloc, zfree functions */
3482 extern int inflate_trees_fixed OF((
3483 uIntf *, /* literal desired/actual bit depth */
3484 uIntf *, /* distance desired/actual bit depth */
3485 inflate_huft * FAR *, /* literal/length tree result */
3486 inflate_huft * FAR *)); /* distance tree result */
3488 extern int inflate_trees_free OF((
3489 inflate_huft *, /* tables to free */
3490 z_streamp )); /* for zfree function */
3492 /* --- inftrees.h */
3494 /* +++ infcodes.h */
3495 /* infcodes.h -- header to use infcodes.c
3496 * Copyright (C) 1995-1996 Mark Adler
3497 * For conditions of distribution and use, see copyright notice in zlib.h
3500 /* WARNING: this file should *not* be used by applications. It is
3501 part of the implementation of the compression library and is
3502 subject to change. Applications should only use zlib.h.
3505 struct inflate_codes_state;
3506 typedef struct inflate_codes_state FAR inflate_codes_statef;
3508 extern inflate_codes_statef *inflate_codes_new OF((
3510 inflate_huft *, inflate_huft *,
3513 extern int inflate_codes OF((
3514 inflate_blocks_statef *,
3518 extern void inflate_codes_free OF((
3519 inflate_codes_statef *,
3522 /* --- infcodes.h */
3525 /* infutil.h -- types and macros common to blocks and codes
3526 * Copyright (C) 1995-1996 Mark Adler
3527 * For conditions of distribution and use, see copyright notice in zlib.h
3530 /* WARNING: this file should *not* be used by applications. It is
3531 part of the implementation of the compression library and is
3532 subject to change. Applications should only use zlib.h.
3539 TYPE, /* get type bits (3, including end bit) */
3540 LENS, /* get lengths for stored */
3541 STORED, /* processing stored block */
3542 TABLE, /* get table lengths */
3543 BTREE, /* get bit lengths tree for a dynamic block */
3544 DTREE, /* get length, distance trees for a dynamic block */
3545 CODES, /* processing fixed or dynamic block */
3546 DRY, /* output remaining window bytes */
3547 DONEB, /* finished last block, done */
3548 BADB} /* got a data error--stuck here */
3551 /* inflate blocks semi-private state */
3552 struct inflate_blocks_state {
3555 inflate_block_mode mode; /* current inflate_block mode */
3557 /* mode dependent information */
3559 uInt left; /* if STORED, bytes left to copy */
3561 uInt table; /* table lengths (14 bits) */
3562 uInt index; /* index into blens (or border) */
3563 uIntf *blens; /* bit lengths of codes */
3564 uInt bb; /* bit length tree depth */
3565 inflate_huft *tb; /* bit length decoding tree */
3566 } trees; /* if DTREE, decoding info for trees */
3569 inflate_huft *td; /* trees to free */
3570 inflate_codes_statef
3572 } decode; /* if CODES, current state */
3573 } sub; /* submode */
3574 uInt last; /* true if this block is the last block */
3576 /* mode independent information */
3577 uInt bitk; /* bits in bit buffer */
3578 uLong bitb; /* bit buffer */
3579 Bytef *window; /* sliding window */
3580 Bytef *end; /* one byte after sliding window */
3581 Bytef *read; /* window read pointer */
3582 Bytef *write; /* window write pointer */
3583 check_func checkfn; /* check function */
3584 uLong check; /* check on output */
3589 /* defines for inflate input/output */
3590 /* update pointers and return */
3591 #define UPDBITS {s->bitb=b;s->bitk=k;}
3592 #define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
3593 #define UPDOUT {s->write=q;}
3594 #define UPDATE {UPDBITS UPDIN UPDOUT}
3595 #define LEAVE {UPDATE return inflate_flush(s,z,r);}
3596 /* get bytes and bits */
3597 #define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
3598 #define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
3599 #define NEXTBYTE (n--,*p++)
3600 #define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
3601 #define DUMPBITS(j) {b>>=(j);k-=(j);}
3603 #define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q)
3604 #define LOADOUT {q=s->write;m=(uInt)WAVAIL;}
3605 #define WWRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}}
3606 #define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
3607 #define NEEDOUT {if(m==0){WWRAP if(m==0){FLUSH WWRAP if(m==0) LEAVE}}r=Z_OK;}
3608 #define OUTBYTE(a) {*q++=(Byte)(a);m--;}
3609 /* load local pointers */
3610 #define LOAD {LOADIN LOADOUT}
3612 /* masks for lower bits (size given to avoid silly warnings with Visual C++) */
3613 extern uInt inflate_mask[17];
3615 /* copy as much as possible from the sliding window to the output area */
3616 extern int inflate_flush OF((
3617 inflate_blocks_statef *,
3621 #ifndef NO_DUMMY_DECL
3622 struct internal_state {int dummy;}; /* for buggy compilers */
3628 #ifndef NO_DUMMY_DECL
3629 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
3632 /* Table for deflate from PKZIP's appnote.txt. */
3633 local const uInt border[] = { /* Order of the bit length code lengths */
3634 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
3637 Notes beyond the 1.93a appnote.txt:
3639 1. Distance pointers never point before the beginning of the output
3641 2. Distance pointers can point back across blocks, up to 32k away.
3642 3. There is an implied maximum of 7 bits for the bit length table and
3643 15 bits for the actual data.
3644 4. If only one code exists, then it is encoded using one bit. (Zero
3645 would be more efficient, but perhaps a little confusing.) If two
3646 codes exist, they are coded using one bit each (0 and 1).
3647 5. There is no way of sending zero distance codes--a dummy must be
3648 sent if there are none. (History: a pre 2.0 version of PKZIP would
3649 store blocks with no distance codes, but this was discovered to be
3650 too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
3651 zero distance codes, which is sent as one code of zero bits in
3653 6. There are up to 286 literal/length codes. Code 256 represents the
3654 end-of-block. Note however that the static length tree defines
3655 288 codes just to fill out the Huffman codes. Codes 286 and 287
3656 cannot be used though, since there is no length base or extra bits
3657 defined for them. Similarily, there are up to 30 distance codes.
3658 However, static trees define 32 codes (all 5 bits) to fill out the
3659 Huffman codes, but the last two had better not show up in the data.
3660 7. Unzip can check dynamic Huffman blocks for complete code sets.
3661 The exception is that a single code would not be complete (see #4).
3662 8. The five bits following the block type is really the number of
3663 literal codes sent minus 257.
3664 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
3665 (1+6+6). Therefore, to output three times the length, you output
3666 three codes (1+1+1), whereas to output four times the same length,
3667 you only need two codes (1+3). Hmm.
3668 10. In the tree reconstruction algorithm, Code = Code + Increment
3669 only if BitLength(i) is not zero. (Pretty obvious.)
3670 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
3671 12. Note: length code 284 can represent 227-258, but length code 285
3672 really is 258. The last length deserves its own, short code
3673 since it gets used a lot in very redundant files. The length
3674 258 is special since 258 - 3 (the min match length) is 255.
3675 13. The literal/length and distance code bit lengths are read as a
3676 single stream of lengths. It is possible (and advantageous) for
3677 a repeat code (16, 17, or 18) to go across the boundary between
3678 the two sets of lengths.
3682 void inflate_blocks_reset(s, z, c)
3683 inflate_blocks_statef *s;
3687 if (s->checkfn != Z_NULL)
3689 if (s->mode == BTREE || s->mode == DTREE)
3690 ZFREE(z, s->sub.trees.blens);
3691 if (s->mode == CODES)
3693 inflate_codes_free(s->sub.decode.codes, z);
3694 inflate_trees_free(s->sub.decode.td, z);
3695 inflate_trees_free(s->sub.decode.tl, z);
3700 s->read = s->write = s->window;
3701 if (s->checkfn != Z_NULL)
3702 z->adler = s->check = (*s->checkfn)(0L, Z_NULL, 0);
3703 Trace((stderr, "inflate: blocks reset\n"));
3707 inflate_blocks_statef *inflate_blocks_new(z, c, w)
3712 inflate_blocks_statef *s;
3714 if ((s = (inflate_blocks_statef *)ZALLOC
3715 (z,1,sizeof(struct inflate_blocks_state))) == Z_NULL)
3717 if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL)
3722 s->end = s->window + w;
3725 Trace((stderr, "inflate: blocks allocated\n"));
3726 inflate_blocks_reset(s, z, &s->check);
3732 extern uInt inflate_hufts;
3734 int inflate_blocks(s, z, r)
3735 inflate_blocks_statef *s;
3739 uInt t; /* temporary storage */
3740 uLong b; /* bit buffer */
3741 uInt k; /* bits in bit buffer */
3742 Bytef *p; /* input data pointer */
3743 uInt n; /* bytes available there */
3744 Bytef *q; /* output window write pointer */
3745 uInt m; /* bytes to end of window or read pointer */
3747 /* copy input/output information to locals (UPDATE macro restores) */
3750 /* process input based on current state */
3751 while (1) switch (s->mode)
3759 case 0: /* stored */
3760 Trace((stderr, "inflate: stored block%s\n",
3761 s->last ? " (last)" : ""));
3763 t = k & 7; /* go to byte boundary */
3765 s->mode = LENS; /* get length of stored block */
3768 Trace((stderr, "inflate: fixed codes block%s\n",
3769 s->last ? " (last)" : ""));
3772 inflate_huft *tl, *td;
3774 inflate_trees_fixed(&bl, &bd, &tl, &td);
3775 s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z);
3776 if (s->sub.decode.codes == Z_NULL)
3781 s->sub.decode.tl = Z_NULL; /* don't try to free these */
3782 s->sub.decode.td = Z_NULL;
3787 case 2: /* dynamic */
3788 Trace((stderr, "inflate: dynamic codes block%s\n",
3789 s->last ? " (last)" : ""));
3793 case 3: /* illegal */
3796 z->msg = (char*)"invalid block type";
3803 if ((((~b) >> 16) & 0xffff) != (b & 0xffff))
3806 z->msg = (char*)"invalid stored block lengths";
3810 s->sub.left = (uInt)b & 0xffff;
3811 b = k = 0; /* dump bits */
3812 Tracev((stderr, "inflate: stored length %u\n", s->sub.left));
3813 s->mode = s->sub.left ? STORED : (s->last ? DRY : TYPE);
3825 if ((s->sub.left -= t) != 0)
3827 Tracev((stderr, "inflate: stored end, %lu total out\n",
3828 z->total_out + (q >= s->read ? q - s->read :
3829 (s->end - s->read) + (q - s->window))));
3830 s->mode = s->last ? DRY : TYPE;
3834 s->sub.trees.table = t = (uInt)b & 0x3fff;
3835 #ifndef PKZIP_BUG_WORKAROUND
3836 if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
3839 z->msg = (char*)"too many length or distance symbols";
3844 t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
3847 if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
3853 s->sub.trees.index = 0;
3854 Tracev((stderr, "inflate: table sizes ok\n"));
3857 while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10))
3860 s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7;
3863 while (s->sub.trees.index < 19)
3864 s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
3865 s->sub.trees.bb = 7;
3866 t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
3867 &s->sub.trees.tb, z);
3871 if (r == Z_DATA_ERROR) {
3872 ZFREE(z, s->sub.trees.blens);
3877 s->sub.trees.index = 0;
3878 Tracev((stderr, "inflate: bits tree ok\n"));
3881 while (t = s->sub.trees.table,
3882 s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
3887 t = s->sub.trees.bb;
3889 h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]);
3890 t = h->word.what.Bits;
3895 s->sub.trees.blens[s->sub.trees.index++] = c;
3897 else /* c == 16..18 */
3899 i = c == 18 ? 7 : c - 14;
3900 j = c == 18 ? 11 : 3;
3903 j += (uInt)b & inflate_mask[i];
3905 i = s->sub.trees.index;
3906 t = s->sub.trees.table;
3907 if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) ||
3910 inflate_trees_free(s->sub.trees.tb, z);
3911 ZFREE(z, s->sub.trees.blens);
3913 z->msg = (char*)"invalid bit length repeat";
3917 c = c == 16 ? s->sub.trees.blens[i - 1] : 0;
3919 s->sub.trees.blens[i++] = c;
3921 s->sub.trees.index = i;
3924 inflate_trees_free(s->sub.trees.tb, z);
3925 s->sub.trees.tb = Z_NULL;
3928 inflate_huft *tl, *td;
3929 inflate_codes_statef *c;
3931 bl = 9; /* must be <= 9 for lookahead assumptions */
3932 bd = 6; /* must be <= 9 for lookahead assumptions */
3933 t = s->sub.trees.table;
3937 t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
3938 s->sub.trees.blens, &bl, &bd, &tl, &td, z);
3941 if (t == (uInt)Z_DATA_ERROR) {
3942 ZFREE(z, s->sub.trees.blens);
3948 Tracev((stderr, "inflate: trees ok, %d * %d bytes used\n",
3949 inflate_hufts, sizeof(inflate_huft)));
3950 if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
3952 inflate_trees_free(td, z);
3953 inflate_trees_free(tl, z);
3958 * this ZFREE must occur *BEFORE* we mess with sub.decode, because
3959 * sub.trees is union'd with sub.decode.
3961 ZFREE(z, s->sub.trees.blens);
3962 s->sub.decode.codes = c;
3963 s->sub.decode.tl = tl;
3964 s->sub.decode.td = td;
3969 if ((r = inflate_codes(s, z, r)) != Z_STREAM_END)
3970 return inflate_flush(s, z, r);
3972 inflate_codes_free(s->sub.decode.codes, z);
3973 inflate_trees_free(s->sub.decode.td, z);
3974 inflate_trees_free(s->sub.decode.tl, z);
3976 Tracev((stderr, "inflate: codes end, %lu total out\n",
3977 z->total_out + (q >= s->read ? q - s->read :
3978 (s->end - s->read) + (q - s->window))));
3984 if (k > 7) /* return unused byte, if any */
3986 Assert(k < 16, "inflate_codes grabbed too many bytes")
3989 p--; /* can always return one */
3994 if (s->read != s->write)
4010 int inflate_blocks_free(s, z, c)
4011 inflate_blocks_statef *s;
4015 inflate_blocks_reset(s, z, c);
4016 ZFREE(z, s->window);
4018 Trace((stderr, "inflate: blocks freed\n"));
4023 void inflate_set_dictionary(s, d, n)
4024 inflate_blocks_statef *s;
4028 zmemcpy((charf *)s->window, d, n);
4029 s->read = s->write = s->window + n;
4033 * This subroutine adds the data at next_in/avail_in to the output history
4034 * without performing any output. The output buffer must be "caught up";
4035 * i.e. no pending output (hence s->read equals s->write), and the state must
4036 * be BLOCKS (i.e. we should be willing to see the start of a series of
4037 * BLOCKS). On exit, the output will also be caught up, and the checksum
4038 * will have been updated if need be.
4040 int inflate_addhistory(s, z)
4041 inflate_blocks_statef *s;
4044 uLong b; /* bit buffer */ /* NOT USED HERE */
4045 uInt k; /* bits in bit buffer */ /* NOT USED HERE */
4046 uInt t; /* temporary storage */
4047 Bytef *p; /* input data pointer */
4048 uInt n; /* bytes available there */
4049 Bytef *q; /* output window write pointer */
4050 uInt m; /* bytes to end of window or read pointer */
4052 if (s->read != s->write)
4053 return Z_STREAM_ERROR;
4054 if (s->mode != TYPE)
4055 return Z_DATA_ERROR;
4057 /* we're ready to rock */
4059 /* while there is input ready, copy to output buffer, moving
4060 * pointers as needed.
4063 t = n; /* how many to do */
4064 /* is there room until end of buffer? */
4066 /* update check information */
4067 if (s->checkfn != Z_NULL)
4068 s->check = (*s->checkfn)(s->check, q, t);
4074 s->read = q; /* drag read pointer forward */
4075 /* WWRAP */ /* expand WWRAP macro by hand to handle s->read */
4077 s->read = q = s->window;
4087 * At the end of a Deflate-compressed PPP packet, we expect to have seen
4088 * a `stored' block type value but not the (zero) length bytes.
4090 int inflate_packet_flush(s)
4091 inflate_blocks_statef *s;
4093 if (s->mode != LENS)
4094 return Z_DATA_ERROR;
4098 /* --- infblock.c */
4100 /* +++ inftrees.c */
4101 /* inftrees.c -- generate Huffman trees for efficient decoding
4102 * Copyright (C) 1995-1996 Mark Adler
4103 * For conditions of distribution and use, see copyright notice in zlib.h
4106 /* #include "zutil.h" */
4107 /* #include "inftrees.h" */
4110 If you use the zlib library in a product, an acknowledgment is welcome
4111 in the documentation of your product. If for some reason you cannot
4112 include such an acknowledgment, I would appreciate that you keep this
4113 copyright string in the executable of your product.
4116 #ifndef NO_DUMMY_DECL
4117 struct internal_state {int dummy;}; /* for buggy compilers */
4120 /* simplify the use of the inflate_huft type with some defines */
4121 #define base more.Base
4122 #define next more.Next
4123 #define exop word.what.Exop
4124 #define bits word.what.Bits
4127 local int huft_build OF((
4128 uIntf *, /* code lengths in bits */
4129 uInt, /* number of codes */
4130 uInt, /* number of "simple" codes */
4131 const uIntf *, /* list of base values for non-simple codes */
4132 const uIntf *, /* list of extra bits for non-simple codes */
4133 inflate_huft * FAR*,/* result: starting table */
4134 uIntf *, /* maximum lookup bits (returns actual) */
4135 z_streamp )); /* for zalloc function */
4137 local voidpf falloc OF((
4138 voidpf, /* opaque pointer (not used) */
4139 uInt, /* number of items */
4140 uInt)); /* size of item */
4142 /* Tables for deflate from PKZIP's appnote.txt. */
4143 local const uInt cplens[31] = { /* Copy lengths for literal codes 257..285 */
4144 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
4145 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
4146 /* see note #13 above about 258 */
4147 local const uInt cplext[31] = { /* Extra bits for literal codes 257..285 */
4148 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
4149 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 112, 112}; /* 112==invalid */
4150 local const uInt cpdist[30] = { /* Copy offsets for distance codes 0..29 */
4151 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
4152 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
4153 8193, 12289, 16385, 24577};
4154 local const uInt cpdext[30] = { /* Extra bits for distance codes */
4155 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
4156 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
4160 Huffman code decoding is performed using a multi-level table lookup.
4161 The fastest way to decode is to simply build a lookup table whose
4162 size is determined by the longest code. However, the time it takes
4163 to build this table can also be a factor if the data being decoded
4164 is not very long. The most common codes are necessarily the
4165 shortest codes, so those codes dominate the decoding time, and hence
4166 the speed. The idea is you can have a shorter table that decodes the
4167 shorter, more probable codes, and then point to subsidiary tables for
4168 the longer codes. The time it costs to decode the longer codes is
4169 then traded against the time it takes to make longer tables.
4171 This results of this trade are in the variables lbits and dbits
4172 below. lbits is the number of bits the first level table for literal/
4173 length codes can decode in one step, and dbits is the same thing for
4174 the distance codes. Subsequent tables are also less than or equal to
4175 those sizes. These values may be adjusted either when all of the
4176 codes are shorter than that, in which case the longest code length in
4177 bits is used, or when the shortest code is *longer* than the requested
4178 table size, in which case the length of the shortest code in bits is
4181 There are two different values for the two tables, since they code a
4182 different number of possibilities each. The literal/length table
4183 codes 286 possible values, or in a flat code, a little over eight
4184 bits. The distance table codes 30 possible values, or a little less
4185 than five bits, flat. The optimum values for speed end up being
4186 about one bit more than those, so lbits is 8+1 and dbits is 5+1.
4187 The optimum values may differ though from machine to machine, and
4188 possibly even between compilers. Your mileage may vary.
4192 /* If BMAX needs to be larger than 16, then h and x[] should be uLong. */
4193 #define BMAX 15 /* maximum bit length of any code */
4194 #define N_MAX 288 /* maximum number of codes in any set */
4200 local int huft_build(b, n, s, d, e, t, m, zs)
4201 uIntf *b; /* code lengths in bits (all assumed <= BMAX) */
4202 uInt n; /* number of codes (assumed <= N_MAX) */
4203 uInt s; /* number of simple-valued codes (0..s-1) */
4204 const uIntf *d; /* list of base values for non-simple codes */
4205 const uIntf *e; /* list of extra bits for non-simple codes */
4206 inflate_huft * FAR *t; /* result: starting table */
4207 uIntf *m; /* maximum lookup bits, returns actual */
4208 z_streamp zs; /* for zalloc function */
4209 /* Given a list of code lengths and a maximum table size, make a set of
4210 tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR
4211 if the given code set is incomplete (the tables are still built in this
4212 case), Z_DATA_ERROR if the input is invalid (an over-subscribed set of
4213 lengths), or Z_MEM_ERROR if not enough memory. */
4216 uInt a; /* counter for codes of length k */
4217 uInt c[BMAX+1]; /* bit length count table */
4218 uInt f; /* i repeats in table every f entries */
4219 int g; /* maximum code length */
4220 int h; /* table level */
4221 uInt i; /* counter, current code */
4222 uInt j; /* counter */
4223 int k; /* number of bits in current code */
4224 int l; /* bits per table (returned in m) */
4225 uIntf *p; /* pointer into c[], b[], or v[] */
4226 inflate_huft *q; /* points to current table */
4227 struct inflate_huft_s r; /* table entry for structure assignment */
4228 inflate_huft *u[BMAX]; /* table stack */
4229 uInt v[N_MAX]; /* values in order of bit length */
4230 int w; /* bits before this table == (l * h) */
4231 uInt x[BMAX+1]; /* bit offsets, then code stack */
4232 uIntf *xp; /* pointer into x */
4233 int y; /* number of dummy codes added */
4234 uInt z; /* number of entries in current table */
4237 /* Generate counts for each bit length */
4239 #define C0 *p++ = 0;
4240 #define C2 C0 C0 C0 C0
4241 #define C4 C2 C2 C2 C2
4242 C4 /* clear c[]--assume BMAX+1 is 16 */
4245 c[*p++]++; /* assume all entries <= BMAX */
4247 if (c[0] == n) /* null input--all zero length codes */
4249 *t = (inflate_huft *)Z_NULL;
4255 /* Find minimum and maximum length, bound *m by those */
4257 for (j = 1; j <= BMAX; j++)
4260 k = j; /* minimum code length */
4263 for (i = BMAX; i; i--)
4266 g = i; /* maximum code length */
4272 /* Adjust last length count to fill out codes, if needed */
4273 for (y = 1 << j; j < i; j++, y <<= 1)
4274 if ((y -= c[j]) < 0)
4275 return Z_DATA_ERROR;
4276 if ((y -= c[i]) < 0)
4277 return Z_DATA_ERROR;
4281 /* Generate starting offsets into the value table for each length */
4283 p = c + 1; xp = x + 2;
4284 while (--i) { /* note that i == g from above */
4285 *xp++ = (j += *p++);
4289 /* Make a table of values in order of bit lengths */
4292 if ((j = *p++) != 0)
4295 n = x[g]; /* set n to length of v */
4298 /* Generate the Huffman codes and for each, make the table entries */
4299 x[0] = i = 0; /* first Huffman code is zero */
4300 p = v; /* grab values in bit order */
4301 h = -1; /* no tables yet--level -1 */
4302 w = -l; /* bits decoded == (l * h) */
4303 u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */
4304 q = (inflate_huft *)Z_NULL; /* ditto */
4307 /* go through the bit lengths (k already is bits in shortest code) */
4313 /* here i is the Huffman code of length k bits for value *p */
4314 /* make tables up to required level */
4318 w += l; /* previous table always l bits */
4320 /* compute minimum size table less than or equal to l bits */
4322 z = z > (uInt)l ? l : z; /* table size upper limit */
4323 if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
4324 { /* too few codes for k-w bit table */
4325 f -= a + 1; /* deduct codes from patterns left */
4328 while (++j < z) /* try smaller tables up to z bits */
4330 if ((f <<= 1) <= *++xp)
4331 break; /* enough codes to use up j bits */
4332 f -= *xp; /* else deduct codes from patterns */
4335 z = 1 << j; /* table entries for j-bit table */
4337 /* allocate and link in new table */
4338 if ((q = (inflate_huft *)ZALLOC
4339 (zs,z + 1,sizeof(inflate_huft))) == Z_NULL)
4342 inflate_trees_free(u[0], zs);
4343 return Z_MEM_ERROR; /* not enough memory */
4346 inflate_hufts += z + 1;
4348 *t = q + 1; /* link to list for huft_free() */
4349 *(t = &(q->next)) = Z_NULL;
4350 u[h] = ++q; /* table starts after link */
4352 /* connect to last table, if there is one */
4355 x[h] = i; /* save pattern for backing up */
4356 r.bits = (Byte)l; /* bits to dump before this table */
4357 r.exop = (Byte)j; /* bits in this table */
4358 r.next = q; /* pointer to this table */
4359 j = i >> (w - l); /* (get around Turbo C bug) */
4360 u[h-1][j] = r; /* connect to last table */
4364 /* set up table entry in r */
4365 r.bits = (Byte)(k - w);
4367 r.exop = 128 + 64; /* out of values--invalid code */
4370 r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */
4371 r.base = *p++; /* simple code is just the value */
4375 r.exop = (Byte)(e[*p - s] + 16 + 64);/* non-simple--look up in lists */
4376 r.base = d[*p++ - s];
4379 /* fill code-like entries with r */
4381 for (j = i >> w; j < z; j += f)
4384 /* backwards increment the k-bit code i */
4385 for (j = 1 << (k - 1); i & j; j >>= 1)
4389 /* backup over finished tables */
4390 while ((i & ((1 << w) - 1)) != x[h])
4392 h--; /* don't need to update q */
4399 /* Return Z_BUF_ERROR if we were given an incomplete table */
4400 return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK;
4404 int inflate_trees_bits(c, bb, tb, z)
4405 uIntf *c; /* 19 code lengths */
4406 uIntf *bb; /* bits tree desired/actual depth */
4407 inflate_huft * FAR *tb; /* bits tree result */
4408 z_streamp z; /* for zfree function */
4412 r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL, tb, bb, z);
4413 if (r == Z_DATA_ERROR)
4414 z->msg = (char*)"oversubscribed dynamic bit lengths tree";
4415 else if (r == Z_BUF_ERROR || *bb == 0)
4417 inflate_trees_free(*tb, z);
4418 z->msg = (char*)"incomplete dynamic bit lengths tree";
4425 int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, z)
4426 uInt nl; /* number of literal/length codes */
4427 uInt nd; /* number of distance codes */
4428 uIntf *c; /* that many (total) code lengths */
4429 uIntf *bl; /* literal desired/actual bit depth */
4430 uIntf *bd; /* distance desired/actual bit depth */
4431 inflate_huft * FAR *tl; /* literal/length tree result */
4432 inflate_huft * FAR *td; /* distance tree result */
4433 z_streamp z; /* for zfree function */
4437 /* build literal/length tree */
4438 r = huft_build(c, nl, 257, cplens, cplext, tl, bl, z);
4439 if (r != Z_OK || *bl == 0)
4441 if (r == Z_DATA_ERROR)
4442 z->msg = (char*)"oversubscribed literal/length tree";
4443 else if (r != Z_MEM_ERROR)
4445 inflate_trees_free(*tl, z);
4446 z->msg = (char*)"incomplete literal/length tree";
4452 /* build distance tree */
4453 r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, z);
4454 if (r != Z_OK || (*bd == 0 && nl > 257))
4456 if (r == Z_DATA_ERROR)
4457 z->msg = (char*)"oversubscribed distance tree";
4458 else if (r == Z_BUF_ERROR) {
4459 #ifdef PKZIP_BUG_WORKAROUND
4463 inflate_trees_free(*td, z);
4464 z->msg = (char*)"incomplete distance tree";
4467 else if (r != Z_MEM_ERROR)
4469 z->msg = (char*)"empty distance tree with lengths";
4472 inflate_trees_free(*tl, z);
4482 /* build fixed tables only once--keep them here */
4483 local int fixed_built = 0;
4484 #define FIXEDH 530 /* number of hufts used by fixed tables */
4485 local inflate_huft fixed_mem[FIXEDH];
4486 local uInt fixed_bl;
4487 local uInt fixed_bd;
4488 local inflate_huft *fixed_tl;
4489 local inflate_huft *fixed_td;
4492 local voidpf falloc(q, n, s)
4493 voidpf q; /* opaque pointer */
4494 uInt n; /* number of items */
4495 uInt s; /* size of item */
4497 Assert(s == sizeof(inflate_huft) && n <= *(intf *)q,
4498 "inflate_trees falloc overflow");
4499 *(intf *)q -= n+s-s; /* s-s to avoid warning */
4500 return (voidpf)(fixed_mem + *(intf *)q);
4504 int inflate_trees_fixed(bl, bd, tl, td)
4505 uIntf *bl; /* literal desired/actual bit depth */
4506 uIntf *bd; /* distance desired/actual bit depth */
4507 inflate_huft * FAR *tl; /* literal/length tree result */
4508 inflate_huft * FAR *td; /* distance tree result */
4510 /* build fixed tables if not already (multiple overlapped executions ok) */
4513 int k; /* temporary variable */
4514 unsigned c[288]; /* length list for huft_build */
4515 z_stream z; /* for falloc function */
4516 int f = FIXEDH; /* number of hufts left in fixed_mem */
4518 /* set up fake z_stream for memory routines */
4521 z.opaque = (voidpf)&f;
4524 for (k = 0; k < 144; k++)
4526 for (; k < 256; k++)
4528 for (; k < 280; k++)
4530 for (; k < 288; k++)
4533 huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl, &z);
4535 /* distance table */
4536 for (k = 0; k < 30; k++)
4539 huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd, &z);
4542 Assert(f == 0, "invalid build of fixed tables");
4553 int inflate_trees_free(t, z)
4554 inflate_huft *t; /* table to free */
4555 z_streamp z; /* for zfree function */
4556 /* Free the malloc'ed tables built by huft_build(), which makes a linked
4557 list of the tables it made, with the links in a dummy first entry of
4560 inflate_huft *p, *q, *r;
4562 /* Reverse linked list */
4572 /* Go through linked list, freeing from the malloced (t[-1]) address. */
4581 /* --- inftrees.c */
4583 /* +++ infcodes.c */
4584 /* infcodes.c -- process literals and length/distance pairs
4585 * Copyright (C) 1995-1996 Mark Adler
4586 * For conditions of distribution and use, see copyright notice in zlib.h
4589 /* #include "zutil.h" */
4590 /* #include "inftrees.h" */
4591 /* #include "infblock.h" */
4592 /* #include "infcodes.h" */
4593 /* #include "infutil.h" */
4596 /* inffast.h -- header to use inffast.c
4597 * Copyright (C) 1995-1996 Mark Adler
4598 * For conditions of distribution and use, see copyright notice in zlib.h
4601 /* WARNING: this file should *not* be used by applications. It is
4602 part of the implementation of the compression library and is
4603 subject to change. Applications should only use zlib.h.
4606 extern int inflate_fast OF((
4611 inflate_blocks_statef *,
4615 /* simplify the use of the inflate_huft type with some defines */
4616 #define base more.Base
4617 #define next more.Next
4618 #define exop word.what.Exop
4619 #define bits word.what.Bits
4621 /* inflate codes private state */
4622 struct inflate_codes_state {
4625 enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
4626 START, /* x: set up for LEN */
4627 LEN, /* i: get length/literal/eob next */
4628 LENEXT, /* i: getting length extra (have base) */
4629 DIST, /* i: get distance next */
4630 DISTEXT, /* i: getting distance extra */
4631 COPY, /* o: copying bytes in window, waiting for space */
4632 LIT, /* o: got literal, waiting for output space */
4633 WASH, /* o: got eob, possibly still output waiting */
4634 END, /* x: got eob and all data flushed */
4635 BADCODE} /* x: got error */
4636 mode; /* current inflate_codes mode */
4638 /* mode dependent information */
4642 inflate_huft *tree; /* pointer into tree */
4643 uInt need; /* bits needed */
4644 } code; /* if LEN or DIST, where in tree */
4645 uInt lit; /* if LIT, literal */
4647 uInt get; /* bits to get for extra */
4648 uInt dist; /* distance back to copy from */
4649 } copy; /* if EXT or COPY, where and how much */
4650 } sub; /* submode */
4652 /* mode independent information */
4653 Byte lbits; /* ltree bits decoded per branch */
4654 Byte dbits; /* dtree bits decoder per branch */
4655 inflate_huft *ltree; /* literal/length/eob tree */
4656 inflate_huft *dtree; /* distance tree */
4661 inflate_codes_statef *inflate_codes_new(bl, bd, tl, td, z)
4664 inflate_huft *td; /* need separate declaration for Borland C++ */
4667 inflate_codes_statef *c;
4669 if ((c = (inflate_codes_statef *)
4670 ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL)
4673 c->lbits = (Byte)bl;
4674 c->dbits = (Byte)bd;
4677 Tracev((stderr, "inflate: codes new\n"));
4683 int inflate_codes(s, z, r)
4684 inflate_blocks_statef *s;
4688 uInt j; /* temporary storage */
4689 inflate_huft *t; /* temporary pointer */
4690 uInt e; /* extra bits or operation */
4691 uLong b; /* bit buffer */
4692 uInt k; /* bits in bit buffer */
4693 Bytef *p; /* input data pointer */
4694 uInt n; /* bytes available there */
4695 Bytef *q; /* output window write pointer */
4696 uInt m; /* bytes to end of window or read pointer */
4697 Bytef *f; /* pointer to copy strings from */
4698 inflate_codes_statef *c = s->sub.decode.codes; /* codes state */
4700 /* copy input/output information to locals (UPDATE macro restores) */
4703 /* process input and output based on current state */
4704 while (1) switch (c->mode)
4705 { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
4706 case START: /* x: set up for LEN */
4708 if (m >= 258 && n >= 10)
4711 r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z);
4715 c->mode = r == Z_STREAM_END ? WASH : BADCODE;
4720 c->sub.code.need = c->lbits;
4721 c->sub.code.tree = c->ltree;
4723 case LEN: /* i: get length/literal/eob next */
4724 j = c->sub.code.need;
4726 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
4728 e = (uInt)(t->exop);
4729 if (e == 0) /* literal */
4731 c->sub.lit = t->base;
4732 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
4733 "inflate: literal '%c'\n" :
4734 "inflate: literal 0x%02x\n", t->base));
4738 if (e & 16) /* length */
4740 c->sub.copy.get = e & 15;
4745 if ((e & 64) == 0) /* next table */
4747 c->sub.code.need = e;
4748 c->sub.code.tree = t->next;
4751 if (e & 32) /* end of block */
4753 Tracevv((stderr, "inflate: end of block\n"));
4757 c->mode = BADCODE; /* invalid code */
4758 z->msg = (char*)"invalid literal/length code";
4761 case LENEXT: /* i: getting length extra (have base) */
4762 j = c->sub.copy.get;
4764 c->len += (uInt)b & inflate_mask[j];
4766 c->sub.code.need = c->dbits;
4767 c->sub.code.tree = c->dtree;
4768 Tracevv((stderr, "inflate: length %u\n", c->len));
4770 case DIST: /* i: get distance next */
4771 j = c->sub.code.need;
4773 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
4775 e = (uInt)(t->exop);
4776 if (e & 16) /* distance */
4778 c->sub.copy.get = e & 15;
4779 c->sub.copy.dist = t->base;
4783 if ((e & 64) == 0) /* next table */
4785 c->sub.code.need = e;
4786 c->sub.code.tree = t->next;
4789 c->mode = BADCODE; /* invalid code */
4790 z->msg = (char*)"invalid distance code";
4793 case DISTEXT: /* i: getting distance extra */
4794 j = c->sub.copy.get;
4796 c->sub.copy.dist += (uInt)b & inflate_mask[j];
4798 Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist));
4800 case COPY: /* o: copying bytes in window, waiting for space */
4801 #ifndef __TURBOC__ /* Turbo C bug for following expression */
4802 f = (uInt)(q - s->window) < c->sub.copy.dist ?
4803 s->end - (c->sub.copy.dist - (q - s->window)) :
4804 q - c->sub.copy.dist;
4806 f = q - c->sub.copy.dist;
4807 if ((uInt)(q - s->window) < c->sub.copy.dist)
4808 f = s->end - (c->sub.copy.dist - (uInt)(q - s->window));
4820 case LIT: /* o: got literal, waiting for output space */
4825 case WASH: /* o: got eob, possibly more output */
4827 if (s->read != s->write)
4833 case BADCODE: /* x: got error */
4843 void inflate_codes_free(c, z)
4844 inflate_codes_statef *c;
4848 Tracev((stderr, "inflate: codes free\n"));
4850 /* --- infcodes.c */
4853 /* inflate_util.c -- data and routines common to blocks and codes
4854 * Copyright (C) 1995-1996 Mark Adler
4855 * For conditions of distribution and use, see copyright notice in zlib.h
4858 /* #include "zutil.h" */
4859 /* #include "infblock.h" */
4860 /* #include "inftrees.h" */
4861 /* #include "infcodes.h" */
4862 /* #include "infutil.h" */
4864 #ifndef NO_DUMMY_DECL
4865 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
4868 /* And'ing with mask[n] masks the lower n bits */
4869 uInt inflate_mask[17] = {
4871 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
4872 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
4876 /* copy as much as possible from the sliding window to the output area */
4877 int inflate_flush(s, z, r)
4878 inflate_blocks_statef *s;
4886 /* local copies of source and destination pointers */
4890 /* compute number of bytes to copy as far as end of window */
4891 n = (uInt)((q <= s->write ? s->write : s->end) - q);
4892 if (n > z->avail_out) n = z->avail_out;
4893 if (n && r == Z_BUF_ERROR) r = Z_OK;
4895 /* update counters */
4899 /* update check information */
4900 if (s->checkfn != Z_NULL)
4901 z->adler = s->check = (*s->checkfn)(s->check, q, n);
4903 /* copy as far as end of window */
4910 /* see if more to copy at beginning of window */
4915 if (s->write == s->end)
4916 s->write = s->window;
4918 /* compute bytes to copy */
4919 n = (uInt)(s->write - q);
4920 if (n > z->avail_out) n = z->avail_out;
4921 if (n && r == Z_BUF_ERROR) r = Z_OK;
4923 /* update counters */
4927 /* update check information */
4928 if (s->checkfn != Z_NULL)
4929 z->adler = s->check = (*s->checkfn)(s->check, q, n);
4939 /* update pointers */
4949 /* inffast.c -- process literals and length/distance pairs fast
4950 * Copyright (C) 1995-1996 Mark Adler
4951 * For conditions of distribution and use, see copyright notice in zlib.h
4954 /* #include "zutil.h" */
4955 /* #include "inftrees.h" */
4956 /* #include "infblock.h" */
4957 /* #include "infcodes.h" */
4958 /* #include "infutil.h" */
4959 /* #include "inffast.h" */
4961 #ifndef NO_DUMMY_DECL
4962 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
4965 /* simplify the use of the inflate_huft type with some defines */
4966 #define base more.Base
4967 #define next more.Next
4968 #define exop word.what.Exop
4969 #define bits word.what.Bits
4971 /* macros for bit input with no checking and for returning unused bytes */
4972 #define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}}
4973 #define UNGRAB {n+=(c=k>>3);p-=c;k&=7;}
4975 /* Called with number of bytes left to write in window at least 258
4976 (the maximum string length) and number of input bytes available
4977 at least ten. The ten bytes are six bytes for the longest length/
4978 distance pair plus four bytes for overloading the bit buffer. */
4980 int inflate_fast(bl, bd, tl, td, s, z)
4983 inflate_huft *td; /* need separate declaration for Borland C++ */
4984 inflate_blocks_statef *s;
4987 inflate_huft *t; /* temporary pointer */
4988 uInt e; /* extra bits or operation */
4989 uLong b; /* bit buffer */
4990 uInt k; /* bits in bit buffer */
4991 Bytef *p; /* input data pointer */
4992 uInt n; /* bytes available there */
4993 Bytef *q; /* output window write pointer */
4994 uInt m; /* bytes to end of window or read pointer */
4995 uInt ml; /* mask for literal/length tree */
4996 uInt md; /* mask for distance tree */
4997 uInt c; /* bytes to copy */
4998 uInt d; /* distance back to copy from */
4999 Bytef *r; /* copy source pointer */
5001 /* load input, output, bit values */
5004 /* initialize masks */
5005 ml = inflate_mask[bl];
5006 md = inflate_mask[bd];
5008 /* do until not enough input or output space for fast loop */
5009 do { /* assume called with m >= 258 && n >= 10 */
5010 /* get literal/length code */
5011 GRABBITS(20) /* max bits for literal/length code */
5012 if ((e = (t = tl + ((uInt)b & ml))->exop) == 0)
5015 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5016 "inflate: * literal '%c'\n" :
5017 "inflate: * literal 0x%02x\n", t->base));
5018 *q++ = (Byte)t->base;
5026 /* get extra bits for length */
5028 c = t->base + ((uInt)b & inflate_mask[e]);
5030 Tracevv((stderr, "inflate: * length %u\n", c));
5032 /* decode distance base of block to copy */
5033 GRABBITS(15); /* max bits for distance code */
5034 e = (t = td + ((uInt)b & md))->exop;
5039 /* get extra bits to add to distance base */
5041 GRABBITS(e) /* get extra bits (up to 13) */
5042 d = t->base + ((uInt)b & inflate_mask[e]);
5044 Tracevv((stderr, "inflate: * distance %u\n", d));
5048 if ((uInt)(q - s->window) >= d) /* offset before dest */
5051 *q++ = *r++; c--; /* minimum count is three, */
5052 *q++ = *r++; c--; /* so unroll loop a little */
5054 else /* else offset after destination */
5056 e = d - (uInt)(q - s->window); /* bytes from offset to end */
5057 r = s->end - e; /* pointer to offset */
5058 if (c > e) /* if source crosses, */
5060 c -= e; /* copy to end of window */
5064 r = s->window; /* copy rest from start of window */
5067 do { /* copy all or what's left */
5072 else if ((e & 64) == 0)
5073 e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop;
5076 z->msg = (char*)"invalid distance code";
5079 return Z_DATA_ERROR;
5086 if ((e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop) == 0)
5089 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5090 "inflate: * literal '%c'\n" :
5091 "inflate: * literal 0x%02x\n", t->base));
5092 *q++ = (Byte)t->base;
5099 Tracevv((stderr, "inflate: * end of block\n"));
5102 return Z_STREAM_END;
5106 z->msg = (char*)"invalid literal/length code";
5109 return Z_DATA_ERROR;
5112 } while (m >= 258 && n >= 10);
5114 /* not enough input or output--restore pointers and return */
5122 /* zutil.c -- target dependent utility functions for the compression library
5123 * Copyright (C) 1995-1996 Jean-loup Gailly.
5124 * For conditions of distribution and use, see copyright notice in zlib.h
5127 /* From: zutil.c,v 1.17 1996/07/24 13:41:12 me Exp $ */
5133 /* #include "zutil.h" */
5135 #ifndef NO_DUMMY_DECL
5136 struct internal_state {int dummy;}; /* for buggy compilers */
5140 extern void exit OF((int));
5143 static const char *z_errmsg[10] = {
5144 "need dictionary", /* Z_NEED_DICT 2 */
5145 "stream end", /* Z_STREAM_END 1 */
5147 "file error", /* Z_ERRNO (-1) */
5148 "stream error", /* Z_STREAM_ERROR (-2) */
5149 "data error", /* Z_DATA_ERROR (-3) */
5150 "insufficient memory", /* Z_MEM_ERROR (-4) */
5151 "buffer error", /* Z_BUF_ERROR (-5) */
5152 "incompatible version",/* Z_VERSION_ERROR (-6) */
5156 const char *zlibVersion()
5158 return ZLIB_VERSION;
5165 fprintf(stderr, "%s\n", m);
5172 void zmemcpy(dest, source, len)
5177 if (len == 0) return;
5179 *dest++ = *source++; /* ??? to be unrolled */
5180 } while (--len != 0);
5183 int zmemcmp(s1, s2, len)
5190 for (j = 0; j < len; j++) {
5191 if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
5196 void zmemzero(dest, len)
5200 if (len == 0) return;
5202 *dest++ = 0; /* ??? to be unrolled */
5203 } while (--len != 0);
5208 #if (defined( __BORLANDC__) || !defined(SMALL_MEDIUM)) && !defined(__32BIT__)
5209 /* Small and medium model in Turbo C are for now limited to near allocation
5210 * with reduced MAX_WBITS and MAX_MEM_LEVEL
5214 /* Turbo C malloc() does not allow dynamic allocation of 64K bytes
5215 * and farmalloc(64K) returns a pointer with an offset of 8, so we
5216 * must fix the pointer. Warning: the pointer must be put back to its
5217 * original form in order to free it, use zcfree().
5223 local int next_ptr = 0;
5225 typedef struct ptr_table_s {
5230 local ptr_table table[MAX_PTR];
5231 /* This table is used to remember the original form of pointers
5232 * to large buffers (64K). Such pointers are normalized with a zero offset.
5233 * Since MSDOS is not a preemptive multitasking OS, this table is not
5234 * protected from concurrent access. This hack doesn't work anyway on
5235 * a protected system like OS/2. Use Microsoft C instead.
5238 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5240 voidpf buf = opaque; /* just to make some compilers happy */
5241 ulg bsize = (ulg)items*size;
5243 /* If we allocate less than 65520 bytes, we assume that farmalloc
5244 * will return a usable pointer which doesn't have to be normalized.
5246 if (bsize < 65520L) {
5247 buf = farmalloc(bsize);
5248 if (*(ush*)&buf != 0) return buf;
5250 buf = farmalloc(bsize + 16L);
5252 if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
5253 table[next_ptr].org_ptr = buf;
5255 /* Normalize the pointer to seg:0 */
5256 *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
5258 table[next_ptr++].new_ptr = buf;
5262 void zcfree (voidpf opaque, voidpf ptr)
5265 if (*(ush*)&ptr != 0) { /* object < 64K */
5269 /* Find the original pointer */
5270 for (n = 0; n < next_ptr; n++) {
5271 if (ptr != table[n].new_ptr) continue;
5273 farfree(table[n].org_ptr);
5274 while (++n < next_ptr) {
5275 table[n-1] = table[n];
5280 ptr = opaque; /* just to make some compilers happy */
5281 Assert(0, "zcfree: ptr not found");
5284 #endif /* __TURBOC__ */
5287 #if defined(M_I86) && !defined(__32BIT__)
5288 /* Microsoft C in 16-bit mode */
5292 #if (!defined(_MSC_VER) || (_MSC_VER < 600))
5293 # define _halloc halloc
5294 # define _hfree hfree
5297 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5299 if (opaque) opaque = 0; /* to make compiler happy */
5300 return _halloc((long)items, size);
5303 void zcfree (voidpf opaque, voidpf ptr)
5305 if (opaque) opaque = 0; /* to make compiler happy */
5312 #ifndef MY_ZCALLOC /* Any system without a special alloc function */
5315 extern voidp calloc OF((uInt items, uInt size));
5316 extern void free OF((voidpf ptr));
5319 voidpf zcalloc (opaque, items, size)
5324 if (opaque) items += size - size; /* make compiler happy */
5325 return (voidpf)calloc(items, size);
5328 void zcfree (opaque, ptr)
5333 if (opaque) return; /* make compiler happy */
5336 #endif /* MY_ZCALLOC */
5340 /* adler32.c -- compute the Adler-32 checksum of a data stream
5341 * Copyright (C) 1995-1996 Mark Adler
5342 * For conditions of distribution and use, see copyright notice in zlib.h
5345 /* From: adler32.c,v 1.10 1996/05/22 11:52:18 me Exp $ */
5347 /* #include "zlib.h" */
5349 #define BASE 65521L /* largest prime smaller than 65536 */
5351 /* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
5353 #define DO1(buf,i) {s1 += buf[(i)]; s2 += s1;}
5354 #define DO2(buf,i) DO1(buf,i); DO1(buf,(i)+1);
5355 #define DO4(buf,i) DO2(buf,i); DO2(buf,(i)+2);
5356 #define DO8(buf,i) DO4(buf,i); DO4(buf,(i)+4);
5357 #define DO16(buf) DO8(buf,0); DO8(buf,8);
5359 /* ========================================================================= */
5360 uLong adler32(adler, buf, len)
5365 unsigned long s1 = adler & 0xffff;
5366 unsigned long s2 = (adler >> 16) & 0xffff;
5369 if (buf == Z_NULL) return 1L;
5372 k = len < NMAX ? len : NMAX;
5386 return (s2 << 16) | s1;