1 //==========================================================================
5 //==========================================================================
6 //####ECOSGPLCOPYRIGHTBEGIN####
7 // -------------------------------------------
8 // This file is part of eCos, the Embedded Configurable Operating System.
9 // Portions created by Nick Garnett are
10 // Copyright (C) 2003 eCosCentric Ltd.
12 // eCos is free software; you can redistribute it and/or modify it under
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16 // eCos is distributed in the hope that it will be useful, but WITHOUT ANY
17 // WARRANTY; without even the implied warranty of MERCHANTABILITY or
18 // FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
21 // You should have received a copy of the GNU General Public License along
22 // with eCos; if not, write to the Free Software Foundation, Inc.,
23 // 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
25 // As a special exception, if other files instantiate templates or use macros
26 // or inline functions from this file, or you compile this file and link it
27 // with other works to produce a work based on this file, this file does not
28 // by itself cause the resulting work to be covered by the GNU General Public
29 // License. However the source code for this file must still be made available
30 // in accordance with section (3) of the GNU General Public License.
32 // This exception does not invalidate any other reasons why a work based on
33 // this file might be covered by the GNU General Public License.
35 // -------------------------------------------
36 //####ECOSGPLCOPYRIGHTEND####
37 //####BSDCOPYRIGHTBEGIN####
39 // -------------------------------------------
41 // Portions of this software may have been derived from OpenBSD,
42 // FreeBSD or other sources, and are covered by the appropriate
43 // copyright disclaimers included herein.
45 // -------------------------------------------
47 //####BSDCOPYRIGHTEND####
48 //==========================================================================
51 * This file is derived from various .h and .c files from the zlib-1.0.4
52 * distribution by Jean-loup Gailly and Mark Adler, with some additions
53 * by Paul Mackerras to aid in implementing Deflate compression and
54 * decompression for PPP packets. See zlib.h for conditions of
55 * distribution and use.
57 * Changes that have been made include:
58 * - added Z_PACKET_FLUSH (see zlib.h for details)
59 * - added inflateIncomp and deflateOutputPending
60 * - allow strm->next_out to be NULL, meaning discard the output
62 * $FreeBSD: src/sys/net/zlib.c,v 1.10.6.2 2002/03/24 23:23:58 jedgar Exp $
66 * ==FILEVERSION 971210==
68 * This marker is used by the Linux installation script to determine
69 * whether an up-to-date version of this file is already installed.
78 #if 1 //defined(__FreeBSD__) && defined(_KERNEL)
79 #define inflate inflate_ppp /* FreeBSD already has an inflate :-( */
84 /* zutil.h -- internal interface and configuration of the compression library
85 * Copyright (C) 1995-1996 Jean-loup Gailly.
86 * For conditions of distribution and use, see copyright notice in zlib.h
89 /* WARNING: this file should *not* be used by applications. It is
90 part of the implementation of the compression library and is
91 subject to change. Applications should only use zlib.h.
94 /* From: zutil.h,v 1.16 1996/07/24 13:41:13 me Exp $ */
100 #include <cyg/ppp/net/zlib.h>
106 /* Assume this is a *BSD or SVR4 kernel */
107 #include <sys/param.h>
108 #include <sys/types.h>
109 #include <sys/time.h>
110 //#include <sys/systm.h>
113 # define memcpy(d, s, n) bcopy((s), (d), (n))
114 # define memset(d, v, n) bzero((d), (n))
118 //# include <stdlib.h>
122 #if defined(__KERNEL__)
123 /* Assume this is a Linux kernel */
124 #include <linux/string.h>
127 #else /* not kernel */
129 #if defined(MSDOS)||defined(VMS)||defined(CRAY)||defined(WIN32)||defined(RISCOS)
139 #endif /* __KERNEL__ */
143 # define local static
145 /* compile with -Dlocal if your debugger can't find static symbols */
147 typedef unsigned char uch;
148 typedef uch FAR uchf;
149 typedef unsigned short ush;
150 typedef ush FAR ushf;
151 typedef unsigned long ulg;
153 extern const char *z_errmsg[10]; /* indexed by 2-zlib_error */
154 /* (size given to avoid silly warnings with Visual C++) */
156 #define ERR_MSG(err) z_errmsg[Z_NEED_DICT-(err)]
158 #define ERR_RETURN(strm,err) \
159 return (strm->msg = (const char*)ERR_MSG(err), (err))
160 /* To be used only when the state is known to be valid */
162 /* common constants */
165 # define DEF_WBITS MAX_WBITS
167 /* default windowBits for decompression. MAX_WBITS is for compression only */
169 #if MAX_MEM_LEVEL >= 8
170 # define DEF_MEM_LEVEL 8
172 # define DEF_MEM_LEVEL MAX_MEM_LEVEL
174 /* default memLevel */
176 #define STORED_BLOCK 0
177 #define STATIC_TREES 1
179 /* The three kinds of block type */
182 #define MAX_MATCH 258
183 /* The minimum and maximum match lengths */
185 #define PRESET_DICT 0x20 /* preset dictionary flag in zlib header */
187 /* target dependencies */
190 # define OS_CODE 0x00
193 # else /* MSC or DJGPP */
199 # define OS_CODE 0x06
202 #ifdef WIN32 /* Window 95 & Windows NT */
203 # define OS_CODE 0x0b
206 #if defined(VAXC) || defined(VMS)
207 # define OS_CODE 0x02
208 # define FOPEN(name, mode) \
209 fopen((name), (mode), "mbc=60", "ctx=stm", "rfm=fix", "mrs=512")
213 # define OS_CODE 0x01
216 #if defined(ATARI) || defined(atarist)
217 # define OS_CODE 0x05
221 # define OS_CODE 0x07
224 #ifdef __50SERIES /* Prime/PRIMOS */
225 # define OS_CODE 0x0F
229 # define OS_CODE 0x0a
232 #if defined(_BEOS_) || defined(RISCOS)
233 # define fdopen(fd,mode) NULL /* No fdopen() */
236 /* Common defaults */
239 # define OS_CODE 0x03 /* assume Unix */
243 # define FOPEN(name, mode) fopen((name), (mode))
249 extern char *strerror OF((int));
250 # define zstrerror(errnum) strerror(errnum)
252 # define zstrerror(errnum) ""
258 #if (defined(M_I86SM) || defined(M_I86MM)) && !defined(_MSC_VER)
259 /* Use our own functions for small and medium model with MSC <= 5.0.
260 * You may have to use the same strategy for Borland C (untested).
264 #if defined(STDC) && !defined(HAVE_MEMCPY) && !defined(NO_MEMCPY)
268 # ifdef SMALL_MEDIUM /* MSDOS small or medium model */
269 # define zmemcpy _fmemcpy
270 # define zmemcmp _fmemcmp
271 # define zmemzero(dest, len) _fmemset(dest, 0, len)
273 # define zmemcpy memcpy
274 # define zmemcmp memcmp
275 # define zmemzero(dest, len) memset(dest, 0, len)
278 extern void zmemcpy OF((Bytef* dest, Bytef* source, uInt len));
279 extern int zmemcmp OF((Bytef* s1, Bytef* s2, uInt len));
280 extern void zmemzero OF((Bytef* dest, uInt len));
283 /* Diagnostic functions */
289 extern void z_error OF((char *m));
290 # define Assert(cond,msg) {if(!(cond)) z_error(msg);}
291 # define Trace(x) fprintf x
292 # define Tracev(x) {if (verbose) fprintf x ;}
293 # define Tracevv(x) {if (verbose>1) fprintf x ;}
294 # define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
295 # define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
297 # define Assert(cond,msg)
302 # define Tracecv(c,x)
306 typedef uLong (*check_func) OF((uLong check, const Bytef *buf, uInt len));
308 voidpf zcalloc OF((voidpf opaque, unsigned items, unsigned size));
309 void zcfree OF((voidpf opaque, voidpf ptr));
311 #define ZALLOC(strm, items, size) \
312 (*((strm)->zalloc))((strm)->opaque, (items), (size))
313 #define ZFREE(strm, addr) (*((strm)->zfree))((strm)->opaque, (voidpf)(addr))
314 #define TRY_FREE(s, p) {if (p) ZFREE(s, p);}
316 #endif /* _Z_UTIL_H */
320 /* deflate.h -- internal compression state
321 * Copyright (C) 1995-1996 Jean-loup Gailly
322 * For conditions of distribution and use, see copyright notice in zlib.h
325 /* WARNING: this file should *not* be used by applications. It is
326 part of the implementation of the compression library and is
327 subject to change. Applications should only use zlib.h.
330 /* From: deflate.h,v 1.10 1996/07/02 12:41:00 me Exp $ */
335 /* #include "zutil.h" */
337 /* ===========================================================================
338 * Internal compression state.
341 #define LENGTH_CODES 29
342 /* number of length codes, not counting the special END_BLOCK code */
345 /* number of literal bytes 0..255 */
347 #define L_CODES (LITERALS+1+LENGTH_CODES)
348 /* number of Literal or Length codes, including the END_BLOCK code */
351 /* number of distance codes */
354 /* number of codes used to transfer the bit lengths */
356 #define HEAP_SIZE (2*L_CODES+1)
357 /* maximum heap size */
360 /* All codes must not exceed MAX_BITS bits */
362 #define INIT_STATE 42
363 #define BUSY_STATE 113
364 #define FINISH_STATE 666
368 /* Data structure describing a single value and its code string. */
369 typedef struct ct_data_s {
371 ush freq; /* frequency count */
372 ush code; /* bit string */
375 ush dad; /* father node in Huffman tree */
376 ush len; /* length of bit string */
385 typedef struct static_tree_desc_s static_tree_desc;
387 typedef struct tree_desc_s {
388 ct_data *dyn_tree; /* the dynamic tree */
389 int max_code; /* largest code with non zero frequency */
390 static_tree_desc *stat_desc; /* the corresponding static tree */
394 typedef Pos FAR Posf;
395 typedef unsigned IPos;
397 /* A Pos is an index in the character window. We use short instead of int to
398 * save space in the various tables. IPos is used only for parameter passing.
401 typedef struct deflate_state {
402 z_streamp strm; /* pointer back to this zlib stream */
403 int status; /* as the name implies */
404 Bytef *pending_buf; /* output still pending */
405 ulg pending_buf_size; /* size of pending_buf */
406 Bytef *pending_out; /* next pending byte to output to the stream */
407 int pending; /* nb of bytes in the pending buffer */
408 int noheader; /* suppress zlib header and adler32 */
409 Byte data_type; /* UNKNOWN, BINARY or ASCII */
410 Byte method; /* STORED (for zip only) or DEFLATED */
411 int last_flush; /* value of flush param for previous deflate call */
413 /* used by deflate.c: */
415 uInt w_size; /* LZ77 window size (32K by default) */
416 uInt w_bits; /* log2(w_size) (8..16) */
417 uInt w_mask; /* w_size - 1 */
420 /* Sliding window. Input bytes are read into the second half of the window,
421 * and move to the first half later to keep a dictionary of at least wSize
422 * bytes. With this organization, matches are limited to a distance of
423 * wSize-MAX_MATCH bytes, but this ensures that IO is always
424 * performed with a length multiple of the block size. Also, it limits
425 * the window size to 64K, which is quite useful on MSDOS.
426 * To do: use the user input buffer as sliding window.
430 /* Actual size of window: 2*wSize, except when the user input buffer
431 * is directly used as sliding window.
435 /* Link to older string with same hash index. To limit the size of this
436 * array to 64K, this link is maintained only for the last 32K strings.
437 * An index in this array is thus a window index modulo 32K.
440 Posf *head; /* Heads of the hash chains or NIL. */
442 uInt ins_h; /* hash index of string to be inserted */
443 uInt hash_size; /* number of elements in hash table */
444 uInt hash_bits; /* log2(hash_size) */
445 uInt hash_mask; /* hash_size-1 */
448 /* Number of bits by which ins_h must be shifted at each input
449 * step. It must be such that after MIN_MATCH steps, the oldest
450 * byte no longer takes part in the hash key, that is:
451 * hash_shift * MIN_MATCH >= hash_bits
455 /* Window position at the beginning of the current output block. Gets
456 * negative when the window is moved backwards.
459 uInt match_length; /* length of best match */
460 IPos prev_match; /* previous match */
461 int match_available; /* set if previous match exists */
462 uInt strstart; /* start of string to insert */
463 uInt match_start; /* start of matching string */
464 uInt lookahead; /* number of valid bytes ahead in window */
467 /* Length of the best match at previous step. Matches not greater than this
468 * are discarded. This is used in the lazy match evaluation.
471 uInt max_chain_length;
472 /* To speed up deflation, hash chains are never searched beyond this
473 * length. A higher limit improves compression ratio but degrades the
478 /* Attempt to find a better match only when the current match is strictly
479 * smaller than this value. This mechanism is used only for compression
482 # define max_insert_length max_lazy_match
483 /* Insert new strings in the hash table only if the match length is not
484 * greater than this length. This saves time but degrades compression.
485 * max_insert_length is used only for compression levels <= 3.
488 int level; /* compression level (1..9) */
489 int strategy; /* favor or force Huffman coding*/
492 /* Use a faster search when the previous match is longer than this */
494 int nice_match; /* Stop searching when current match exceeds this */
496 /* used by trees.c: */
497 /* Didn't use ct_data typedef below to supress compiler warning */
498 struct ct_data_s dyn_ltree[HEAP_SIZE]; /* literal and length tree */
499 struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */
500 struct ct_data_s bl_tree[2*BL_CODES+1]; /* Huffman tree for bit lengths */
502 struct tree_desc_s l_desc; /* desc. for literal tree */
503 struct tree_desc_s d_desc; /* desc. for distance tree */
504 struct tree_desc_s bl_desc; /* desc. for bit length tree */
506 ush bl_count[MAX_BITS+1];
507 /* number of codes at each bit length for an optimal tree */
509 int heap[2*L_CODES+1]; /* heap used to build the Huffman trees */
510 int heap_len; /* number of elements in the heap */
511 int heap_max; /* element of largest frequency */
512 /* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used.
513 * The same heap array is used to build all trees.
516 uch depth[2*L_CODES+1];
517 /* Depth of each subtree used as tie breaker for trees of equal frequency
520 uchf *l_buf; /* buffer for literals or lengths */
523 /* Size of match buffer for literals/lengths. There are 4 reasons for
524 * limiting lit_bufsize to 64K:
525 * - frequencies can be kept in 16 bit counters
526 * - if compression is not successful for the first block, all input
527 * data is still in the window so we can still emit a stored block even
528 * when input comes from standard input. (This can also be done for
529 * all blocks if lit_bufsize is not greater than 32K.)
530 * - if compression is not successful for a file smaller than 64K, we can
531 * even emit a stored file instead of a stored block (saving 5 bytes).
532 * This is applicable only for zip (not gzip or zlib).
533 * - creating new Huffman trees less frequently may not provide fast
534 * adaptation to changes in the input data statistics. (Take for
535 * example a binary file with poorly compressible code followed by
536 * a highly compressible string table.) Smaller buffer sizes give
537 * fast adaptation but have of course the overhead of transmitting
538 * trees more frequently.
539 * - I can't count above 4
542 uInt last_lit; /* running index in l_buf */
545 /* Buffer for distances. To simplify the code, d_buf and l_buf have
546 * the same number of elements. To use different lengths, an extra flag
547 * array would be necessary.
550 ulg opt_len; /* bit length of current block with optimal trees */
551 ulg static_len; /* bit length of current block with static trees */
552 ulg compressed_len; /* total bit length of compressed file */
553 uInt matches; /* number of string matches in current block */
554 int last_eob_len; /* bit length of EOB code for last block */
557 ulg bits_sent; /* bit length of the compressed data */
561 /* Output buffer. bits are inserted starting at the bottom (least
565 /* Number of valid bits in bi_buf. All bits above the last valid bit
571 /* Output a byte on the stream.
572 * IN assertion: there is enough room in pending_buf.
574 #define put_byte(s, c) {s->pending_buf[s->pending++] = (c);}
577 #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
578 /* Minimum amount of lookahead, except at the end of the input file.
579 * See deflate.c for comments about the MIN_MATCH+1.
582 #define MAX_DIST(s) ((s)->w_size-MIN_LOOKAHEAD)
583 /* In order to simplify the code, particularly on 16 bit machines, match
584 * distances are limited to MAX_DIST instead of WSIZE.
588 void _tr_init OF((deflate_state *s));
589 int _tr_tally OF((deflate_state *s, unsigned dist, unsigned lc));
590 ulg _tr_flush_block OF((deflate_state *s, charf *buf, ulg stored_len,
592 void _tr_align OF((deflate_state *s));
593 void _tr_stored_block OF((deflate_state *s, charf *buf, ulg stored_len,
595 void _tr_stored_type_only OF((deflate_state *));
601 /* deflate.c -- compress data using the deflation algorithm
602 * Copyright (C) 1995-1996 Jean-loup Gailly.
603 * For conditions of distribution and use, see copyright notice in zlib.h
609 * The "deflation" process depends on being able to identify portions
610 * of the input text which are identical to earlier input (within a
611 * sliding window trailing behind the input currently being processed).
613 * The most straightforward technique turns out to be the fastest for
614 * most input files: try all possible matches and select the longest.
615 * The key feature of this algorithm is that insertions into the string
616 * dictionary are very simple and thus fast, and deletions are avoided
617 * completely. Insertions are performed at each input character, whereas
618 * string matches are performed only when the previous match ends. So it
619 * is preferable to spend more time in matches to allow very fast string
620 * insertions and avoid deletions. The matching algorithm for small
621 * strings is inspired from that of Rabin & Karp. A brute force approach
622 * is used to find longer strings when a small match has been found.
623 * A similar algorithm is used in comic (by Jan-Mark Wams) and freeze
624 * (by Leonid Broukhis).
625 * A previous version of this file used a more sophisticated algorithm
626 * (by Fiala and Greene) which is guaranteed to run in linear amortized
627 * time, but has a larger average cost, uses more memory and is patented.
628 * However the F&G algorithm may be faster for some highly redundant
629 * files if the parameter max_chain_length (described below) is too large.
633 * The idea of lazy evaluation of matches is due to Jan-Mark Wams, and
634 * I found it in 'freeze' written by Leonid Broukhis.
635 * Thanks to many people for bug reports and testing.
639 * Deutsch, L.P.,"DEFLATE Compressed Data Format Specification".
640 * Available in ftp://ds.internic.net/rfc/rfc1951.txt
642 * A description of the Rabin and Karp algorithm is given in the book
643 * "Algorithms" by R. Sedgewick, Addison-Wesley, p252.
645 * Fiala,E.R., and Greene,D.H.
646 * Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595
650 /* From: deflate.c,v 1.15 1996/07/24 13:40:58 me Exp $ */
652 /* #include "deflate.h" */
654 char deflate_copyright[] = " deflate 1.0.4 Copyright 1995-1996 Jean-loup Gailly ";
656 If you use the zlib library in a product, an acknowledgment is welcome
657 in the documentation of your product. If for some reason you cannot
658 include such an acknowledgment, I would appreciate that you keep this
659 copyright string in the executable of your product.
662 /* ===========================================================================
663 * Function prototypes.
666 need_more, /* block not completed, need more input or more output */
667 block_done, /* block flush performed */
668 finish_started, /* finish started, need only more output at next deflate */
669 finish_done /* finish done, accept no more input or output */
672 typedef block_state (*compress_func) OF((deflate_state *s, int flush));
673 /* Compression function. Returns the block state after the call. */
675 local void fill_window OF((deflate_state *s));
676 local block_state deflate_stored OF((deflate_state *s, int flush));
677 local block_state deflate_fast OF((deflate_state *s, int flush));
678 local block_state deflate_slow OF((deflate_state *s, int flush));
679 local void lm_init OF((deflate_state *s));
680 local void putShortMSB OF((deflate_state *s, uInt b));
681 local void flush_pending OF((z_streamp strm));
682 local int read_buf OF((z_streamp strm, charf *buf, unsigned size));
684 void match_init OF((void)); /* asm code initialization */
685 uInt longest_match OF((deflate_state *s, IPos cur_match));
687 local uInt longest_match OF((deflate_state *s, IPos cur_match));
691 local void check_match OF((deflate_state *s, IPos start, IPos match,
695 /* ===========================================================================
700 /* Tail of hash chains */
703 # define TOO_FAR 4096
705 /* Matches of length 3 are discarded if their distance exceeds TOO_FAR */
707 #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
708 /* Minimum amount of lookahead, except at the end of the input file.
709 * See deflate.c for comments about the MIN_MATCH+1.
712 /* Values for max_lazy_match, good_match and max_chain_length, depending on
713 * the desired pack level (0..9). The values given below have been tuned to
714 * exclude worst case performance for pathological files. Better values may be
715 * found for specific files.
717 typedef struct config_s {
718 ush good_length; /* reduce lazy search above this match length */
719 ush max_lazy; /* do not perform lazy search above this match length */
720 ush nice_length; /* quit search above this match length */
725 local config configuration_table[10] = {
726 /* good lazy nice chain */
727 /* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */
728 /* 1 */ {4, 4, 8, 4, deflate_fast}, /* maximum speed, no lazy matches */
729 /* 2 */ {4, 5, 16, 8, deflate_fast},
730 /* 3 */ {4, 6, 32, 32, deflate_fast},
732 /* 4 */ {4, 4, 16, 16, deflate_slow}, /* lazy matches */
733 /* 5 */ {8, 16, 32, 32, deflate_slow},
734 /* 6 */ {8, 16, 128, 128, deflate_slow},
735 /* 7 */ {8, 32, 128, 256, deflate_slow},
736 /* 8 */ {32, 128, 258, 1024, deflate_slow},
737 /* 9 */ {32, 258, 258, 4096, deflate_slow}}; /* maximum compression */
739 /* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4
740 * For deflate_fast() (levels <= 3) good is ignored and lazy has a different
745 /* result of memcmp for equal strings */
747 #ifndef NO_DUMMY_DECL
748 struct static_tree_desc_s {int dummy;}; /* for buggy compilers */
751 /* ===========================================================================
752 * Update a hash value with the given input byte
753 * IN assertion: all calls to to UPDATE_HASH are made with consecutive
754 * input characters, so that a running hash key can be computed from the
755 * previous key instead of complete recalculation each time.
757 #define UPDATE_HASH(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask)
760 /* ===========================================================================
761 * Insert string str in the dictionary and set match_head to the previous head
762 * of the hash chain (the most recent string with same hash key). Return
763 * the previous length of the hash chain.
764 * IN assertion: all calls to to INSERT_STRING are made with consecutive
765 * input characters and the first MIN_MATCH bytes of str are valid
766 * (except for the last MIN_MATCH-1 bytes of the input file).
768 #define INSERT_STRING(s, str, match_head) \
769 (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
770 s->prev[(str) & s->w_mask] = match_head = s->head[s->ins_h], \
771 s->head[s->ins_h] = (Pos)(str))
773 /* ===========================================================================
774 * Initialize the hash table (avoiding 64K overflow for 16 bit systems).
775 * prev[] will be initialized on the fly.
777 #define CLEAR_HASH(s) \
778 s->head[s->hash_size-1] = NIL; \
779 zmemzero((charf *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head));
781 /* ========================================================================= */
782 int deflateInit_(strm, level, version, stream_size)
788 return deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL,
789 Z_DEFAULT_STRATEGY, version, stream_size);
790 /* To do: ignore strm->next_in if we use it as window */
793 /* ========================================================================= */
794 int deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
795 version, stream_size)
807 static char* my_version = ZLIB_VERSION;
810 /* We overlay pending_buf and d_buf+l_buf. This works since the average
811 * output size for (length,distance) codes is <= 24 bits.
814 if (version == Z_NULL || version[0] != my_version[0] ||
815 stream_size != sizeof(z_stream)) {
816 return Z_VERSION_ERROR;
818 if (strm == Z_NULL) return Z_STREAM_ERROR;
822 if (strm->zalloc == Z_NULL) {
823 strm->zalloc = zcalloc;
824 strm->opaque = (voidpf)0;
826 if (strm->zfree == Z_NULL) strm->zfree = zcfree;
829 if (level == Z_DEFAULT_COMPRESSION) level = 6;
831 if (windowBits < 0) { /* undocumented feature: suppress zlib header */
833 windowBits = -windowBits;
835 if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED ||
836 windowBits < 9 || windowBits > 15 || level < 0 || level > 9 ||
837 strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
838 return Z_STREAM_ERROR;
840 s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state));
841 if (s == Z_NULL) return Z_MEM_ERROR;
842 strm->state = (struct internal_state FAR *)s;
845 s->noheader = noheader;
846 s->w_bits = windowBits;
847 s->w_size = 1 << s->w_bits;
848 s->w_mask = s->w_size - 1;
850 s->hash_bits = memLevel + 7;
851 s->hash_size = 1 << s->hash_bits;
852 s->hash_mask = s->hash_size - 1;
853 s->hash_shift = ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH);
855 s->window = (Bytef *) ZALLOC(strm, s->w_size, 2*sizeof(Byte));
856 s->prev = (Posf *) ZALLOC(strm, s->w_size, sizeof(Pos));
857 s->head = (Posf *) ZALLOC(strm, s->hash_size, sizeof(Pos));
859 s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */
861 overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2);
862 s->pending_buf = (uchf *) overlay;
863 s->pending_buf_size = (ulg)s->lit_bufsize * (sizeof(ush)+2L);
865 if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL ||
866 s->pending_buf == Z_NULL) {
867 strm->msg = (const char*)ERR_MSG(Z_MEM_ERROR);
871 s->d_buf = overlay + s->lit_bufsize/sizeof(ush);
872 s->l_buf = s->pending_buf + (1+sizeof(ush))*s->lit_bufsize;
875 s->strategy = strategy;
876 s->method = (Byte)method;
878 return deflateReset(strm);
881 /* ========================================================================= */
882 int deflateSetDictionary (strm, dictionary, dictLength)
884 const Bytef *dictionary;
888 uInt length = dictLength;
892 if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL)
893 return Z_STREAM_ERROR;
895 s = (deflate_state *) strm->state;
896 if (s->status != INIT_STATE) return Z_STREAM_ERROR;
898 strm->adler = adler32(strm->adler, dictionary, dictLength);
900 if (length < MIN_MATCH) return Z_OK;
901 if (length > MAX_DIST(s)) {
902 length = MAX_DIST(s);
903 #ifndef USE_DICT_HEAD
904 dictionary += dictLength - length; /* use the tail of the dictionary */
907 zmemcpy((charf *)s->window, dictionary, length);
908 s->strstart = length;
909 s->block_start = (long)length;
911 /* Insert all strings in the hash table (except for the last two bytes).
912 * s->lookahead stays null, so s->ins_h will be recomputed at the next
913 * call of fill_window.
915 s->ins_h = s->window[0];
916 UPDATE_HASH(s, s->ins_h, s->window[1]);
917 for (n = 0; n <= length - MIN_MATCH; n++) {
918 INSERT_STRING(s, n, hash_head);
920 if (hash_head) hash_head = 0; /* to make compiler happy */
924 /* ========================================================================= */
925 int deflateReset (strm)
930 if (strm == Z_NULL || strm->state == Z_NULL ||
931 strm->zalloc == Z_NULL || strm->zfree == Z_NULL) return Z_STREAM_ERROR;
933 strm->total_in = strm->total_out = 0;
934 strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */
935 strm->data_type = Z_UNKNOWN;
937 s = (deflate_state *)strm->state;
939 s->pending_out = s->pending_buf;
941 if (s->noheader < 0) {
942 s->noheader = 0; /* was set to -1 by deflate(..., Z_FINISH); */
944 s->status = s->noheader ? BUSY_STATE : INIT_STATE;
946 s->last_flush = Z_NO_FLUSH;
954 /* ========================================================================= */
955 int deflateParams(strm, level, strategy)
964 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
965 s = (deflate_state *) strm->state;
967 if (level == Z_DEFAULT_COMPRESSION) {
970 if (level < 0 || level > 9 || strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
971 return Z_STREAM_ERROR;
973 func = configuration_table[s->level].func;
975 if (func != configuration_table[level].func && strm->total_in != 0) {
976 /* Flush the last buffer: */
977 err = deflate(strm, Z_PARTIAL_FLUSH);
979 if (s->level != level) {
981 s->max_lazy_match = configuration_table[level].max_lazy;
982 s->good_match = configuration_table[level].good_length;
983 s->nice_match = configuration_table[level].nice_length;
984 s->max_chain_length = configuration_table[level].max_chain;
986 s->strategy = strategy;
990 /* =========================================================================
991 * Put a short in the pending buffer. The 16-bit value is put in MSB order.
992 * IN assertion: the stream state is correct and there is enough room in
995 local void putShortMSB (s, b)
999 put_byte(s, (Byte)(b >> 8));
1000 put_byte(s, (Byte)(b & 0xff));
1003 /* =========================================================================
1004 * Flush as much pending output as possible. All deflate() output goes
1005 * through this function so some applications may wish to modify it
1006 * to avoid allocating a large strm->next_out buffer and copying into it.
1007 * (See also read_buf()).
1009 local void flush_pending(strm)
1012 deflate_state *s = (deflate_state *) strm->state;
1013 unsigned len = s->pending;
1015 if (len > strm->avail_out) len = strm->avail_out;
1016 if (len == 0) return;
1018 if (strm->next_out != Z_NULL) {
1019 zmemcpy(strm->next_out, s->pending_out, len);
1020 strm->next_out += len;
1022 s->pending_out += len;
1023 strm->total_out += len;
1024 strm->avail_out -= len;
1026 if (s->pending == 0) {
1027 s->pending_out = s->pending_buf;
1031 /* ========================================================================= */
1032 int deflate (strm, flush)
1036 int old_flush; /* value of flush param for previous deflate call */
1039 if (strm == Z_NULL || strm->state == Z_NULL ||
1040 flush > Z_FINISH || flush < 0) {
1041 return Z_STREAM_ERROR;
1043 s = (deflate_state *) strm->state;
1045 if ((strm->next_in == Z_NULL && strm->avail_in != 0) ||
1046 (s->status == FINISH_STATE && flush != Z_FINISH)) {
1047 ERR_RETURN(strm, Z_STREAM_ERROR);
1049 if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR);
1051 s->strm = strm; /* just in case */
1052 old_flush = s->last_flush;
1053 s->last_flush = flush;
1055 /* Write the zlib header */
1056 if (s->status == INIT_STATE) {
1058 uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8;
1059 uInt level_flags = (s->level-1) >> 1;
1061 if (level_flags > 3) level_flags = 3;
1062 header |= (level_flags << 6);
1063 if (s->strstart != 0) header |= PRESET_DICT;
1064 header += 31 - (header % 31);
1066 s->status = BUSY_STATE;
1067 putShortMSB(s, header);
1069 /* Save the adler32 of the preset dictionary: */
1070 if (s->strstart != 0) {
1071 putShortMSB(s, (uInt)(strm->adler >> 16));
1072 putShortMSB(s, (uInt)(strm->adler & 0xffff));
1077 /* Flush as much pending output as possible */
1078 if (s->pending != 0) {
1079 flush_pending(strm);
1080 if (strm->avail_out == 0) {
1081 /* Since avail_out is 0, deflate will be called again with
1082 * more output space, but possibly with both pending and
1083 * avail_in equal to zero. There won't be anything to do,
1084 * but this is not an error situation so make sure we
1085 * return OK instead of BUF_ERROR at next call of deflate:
1091 /* Make sure there is something to do and avoid duplicate consecutive
1092 * flushes. For repeated and useless calls with Z_FINISH, we keep
1093 * returning Z_STREAM_END instead of Z_BUFF_ERROR.
1095 } else if (strm->avail_in == 0 && flush <= old_flush &&
1096 flush != Z_FINISH) {
1097 ERR_RETURN(strm, Z_BUF_ERROR);
1100 /* User must not provide more input after the first FINISH: */
1101 if (s->status == FINISH_STATE && strm->avail_in != 0) {
1102 ERR_RETURN(strm, Z_BUF_ERROR);
1105 /* Start a new block or continue the current one.
1107 if (strm->avail_in != 0 || s->lookahead != 0 ||
1108 (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) {
1111 bstate = (*(configuration_table[s->level].func))(s, flush);
1113 if (bstate == finish_started || bstate == finish_done) {
1114 s->status = FINISH_STATE;
1116 if (bstate == need_more || bstate == finish_started) {
1117 if (strm->avail_out == 0) {
1118 s->last_flush = -1; /* avoid BUF_ERROR next call, see above */
1121 /* If flush != Z_NO_FLUSH && avail_out == 0, the next call
1122 * of deflate should use the same flush parameter to make sure
1123 * that the flush is complete. So we don't have to output an
1124 * empty block here, this will be done at next call. This also
1125 * ensures that for a very small output buffer, we emit at most
1129 if (bstate == block_done) {
1130 if (flush == Z_PARTIAL_FLUSH) {
1132 } else if (flush == Z_PACKET_FLUSH) {
1133 /* Output just the 3-bit `stored' block type value,
1134 but not a zero length. */
1135 _tr_stored_type_only(s);
1136 } else { /* FULL_FLUSH or SYNC_FLUSH */
1137 _tr_stored_block(s, (char*)0, 0L, 0);
1138 /* For a full flush, this empty block will be recognized
1139 * as a special marker by inflate_sync().
1141 if (flush == Z_FULL_FLUSH) {
1142 CLEAR_HASH(s); /* forget history */
1145 flush_pending(strm);
1146 if (strm->avail_out == 0) {
1147 s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */
1152 Assert(strm->avail_out > 0, "bug2");
1154 if (flush != Z_FINISH) return Z_OK;
1155 if (s->noheader) return Z_STREAM_END;
1157 /* Write the zlib trailer (adler32) */
1158 putShortMSB(s, (uInt)(strm->adler >> 16));
1159 putShortMSB(s, (uInt)(strm->adler & 0xffff));
1160 flush_pending(strm);
1161 /* If avail_out is zero, the application will call deflate again
1162 * to flush the rest.
1164 s->noheader = -1; /* write the trailer only once! */
1165 return s->pending != 0 ? Z_OK : Z_STREAM_END;
1168 /* ========================================================================= */
1169 int deflateEnd (strm)
1175 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
1176 s = (deflate_state *) strm->state;
1179 if (status != INIT_STATE && status != BUSY_STATE &&
1180 status != FINISH_STATE) {
1181 return Z_STREAM_ERROR;
1184 /* Deallocate in reverse order of allocations: */
1185 TRY_FREE(strm, s->pending_buf);
1186 TRY_FREE(strm, s->head);
1187 TRY_FREE(strm, s->prev);
1188 TRY_FREE(strm, s->window);
1191 strm->state = Z_NULL;
1193 return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK;
1196 /* =========================================================================
1197 * Copy the source state to the destination state.
1199 int deflateCopy (dest, source)
1207 if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL)
1208 return Z_STREAM_ERROR;
1209 ss = (deflate_state *) source->state;
1211 zmemcpy(dest, source, sizeof(*dest));
1213 ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state));
1214 if (ds == Z_NULL) return Z_MEM_ERROR;
1215 dest->state = (struct internal_state FAR *) ds;
1216 zmemcpy(ds, ss, sizeof(*ds));
1219 ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte));
1220 ds->prev = (Posf *) ZALLOC(dest, ds->w_size, sizeof(Pos));
1221 ds->head = (Posf *) ZALLOC(dest, ds->hash_size, sizeof(Pos));
1222 overlay = (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2);
1223 ds->pending_buf = (uchf *) overlay;
1225 if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL ||
1226 ds->pending_buf == Z_NULL) {
1230 /* ??? following zmemcpy doesn't work for 16-bit MSDOS */
1231 zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte));
1232 zmemcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos));
1233 zmemcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos));
1234 zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size);
1236 ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf);
1237 ds->d_buf = overlay + ds->lit_bufsize/sizeof(ush);
1238 ds->l_buf = ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize;
1240 ds->l_desc.dyn_tree = ds->dyn_ltree;
1241 ds->d_desc.dyn_tree = ds->dyn_dtree;
1242 ds->bl_desc.dyn_tree = ds->bl_tree;
1247 /* ===========================================================================
1248 * Return the number of bytes of output which are immediately available
1249 * for output from the decompressor.
1251 int deflateOutputPending (strm)
1254 if (strm == Z_NULL || strm->state == Z_NULL) return 0;
1256 return ((deflate_state *)(strm->state))->pending;
1259 /* ===========================================================================
1260 * Read a new buffer from the current input stream, update the adler32
1261 * and total number of bytes read. All deflate() input goes through
1262 * this function so some applications may wish to modify it to avoid
1263 * allocating a large strm->next_in buffer and copying from it.
1264 * (See also flush_pending()).
1266 local int read_buf(strm, buf, size)
1271 unsigned len = strm->avail_in;
1273 if (len > size) len = size;
1274 if (len == 0) return 0;
1276 strm->avail_in -= len;
1278 if (!((deflate_state *)(strm->state))->noheader) {
1279 strm->adler = adler32(strm->adler, strm->next_in, len);
1281 zmemcpy(buf, strm->next_in, len);
1282 strm->next_in += len;
1283 strm->total_in += len;
1288 /* ===========================================================================
1289 * Initialize the "longest match" routines for a new zlib stream
1291 local void lm_init (s)
1294 s->window_size = (ulg)2L*s->w_size;
1298 /* Set the default configuration parameters:
1300 s->max_lazy_match = configuration_table[s->level].max_lazy;
1301 s->good_match = configuration_table[s->level].good_length;
1302 s->nice_match = configuration_table[s->level].nice_length;
1303 s->max_chain_length = configuration_table[s->level].max_chain;
1306 s->block_start = 0L;
1308 s->match_length = s->prev_length = MIN_MATCH-1;
1309 s->match_available = 0;
1312 match_init(); /* initialize the asm code */
1316 /* ===========================================================================
1317 * Set match_start to the longest match starting at the given string and
1318 * return its length. Matches shorter or equal to prev_length are discarded,
1319 * in which case the result is equal to prev_length and match_start is
1321 * IN assertions: cur_match is the head of the hash chain for the current
1322 * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
1323 * OUT assertion: the match length is not greater than s->lookahead.
1326 /* For 80x86 and 680x0, an optimized version will be provided in match.asm or
1327 * match.S. The code will be functionally equivalent.
1329 local uInt longest_match(s, cur_match)
1331 IPos cur_match; /* current match */
1333 unsigned chain_length = s->max_chain_length;/* max hash chain length */
1334 register Bytef *scan = s->window + s->strstart; /* current string */
1335 register Bytef *match; /* matched string */
1336 register int len; /* length of current match */
1337 int best_len = s->prev_length; /* best match length so far */
1338 int nice_match = s->nice_match; /* stop if match long enough */
1339 IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
1340 s->strstart - (IPos)MAX_DIST(s) : NIL;
1341 /* Stop when cur_match becomes <= limit. To simplify the code,
1342 * we prevent matches with the string of window index 0.
1344 Posf *prev = s->prev;
1345 uInt wmask = s->w_mask;
1348 /* Compare two bytes at a time. Note: this is not always beneficial.
1349 * Try with and without -DUNALIGNED_OK to check.
1351 register Bytef *strend = s->window + s->strstart + MAX_MATCH - 1;
1352 register ush scan_start = *(ushf*)scan;
1353 register ush scan_end = *(ushf*)(scan+best_len-1);
1355 register Bytef *strend = s->window + s->strstart + MAX_MATCH;
1356 register Byte scan_end1 = scan[best_len-1];
1357 register Byte scan_end = scan[best_len];
1360 /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
1361 * It is easy to get rid of this optimization if necessary.
1363 Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
1365 /* Do not waste too much time if we already have a good match: */
1366 if (s->prev_length >= s->good_match) {
1369 /* Do not look for matches beyond the end of the input. This is necessary
1370 * to make deflate deterministic.
1372 if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;
1374 Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
1377 Assert(cur_match < s->strstart, "no future");
1378 match = s->window + cur_match;
1380 /* Skip to next match if the match length cannot increase
1381 * or if the match length is less than 2:
1383 #if (defined(UNALIGNED_OK) && MAX_MATCH == 258)
1384 /* This code assumes sizeof(unsigned short) == 2. Do not use
1385 * UNALIGNED_OK if your compiler uses a different size.
1387 if (*(ushf*)(match+best_len-1) != scan_end ||
1388 *(ushf*)match != scan_start) continue;
1390 /* It is not necessary to compare scan[2] and match[2] since they are
1391 * always equal when the other bytes match, given that the hash keys
1392 * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at
1393 * strstart+3, +5, ... up to strstart+257. We check for insufficient
1394 * lookahead only every 4th comparison; the 128th check will be made
1395 * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is
1396 * necessary to put more guard bytes at the end of the window, or
1397 * to check more often for insufficient lookahead.
1399 Assert(scan[2] == match[2], "scan[2]?");
1402 } while (*(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1403 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1404 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1405 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
1407 /* The funny "do {}" generates better code on most compilers */
1409 /* Here, scan <= window+strstart+257 */
1410 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1411 if (*scan == *match) scan++;
1413 len = (MAX_MATCH - 1) - (int)(strend-scan);
1414 scan = strend - (MAX_MATCH-1);
1416 #else /* UNALIGNED_OK */
1418 if (match[best_len] != scan_end ||
1419 match[best_len-1] != scan_end1 ||
1421 *++match != scan[1]) continue;
1423 /* The check at best_len-1 can be removed because it will be made
1424 * again later. (This heuristic is not always a win.)
1425 * It is not necessary to compare scan[2] and match[2] since they
1426 * are always equal when the other bytes match, given that
1427 * the hash keys are equal and that HASH_BITS >= 8.
1430 Assert(*scan == *match, "match[2]?");
1432 /* We check for insufficient lookahead only every 8th comparison;
1433 * the 256th check will be made at strstart+258.
1436 } while (*++scan == *++match && *++scan == *++match &&
1437 *++scan == *++match && *++scan == *++match &&
1438 *++scan == *++match && *++scan == *++match &&
1439 *++scan == *++match && *++scan == *++match &&
1442 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
1444 len = MAX_MATCH - (int)(strend - scan);
1445 scan = strend - MAX_MATCH;
1447 #endif /* UNALIGNED_OK */
1449 if (len > best_len) {
1450 s->match_start = cur_match;
1452 if (len >= nice_match) break;
1454 scan_end = *(ushf*)(scan+best_len-1);
1456 scan_end1 = scan[best_len-1];
1457 scan_end = scan[best_len];
1460 } while ((cur_match = prev[cur_match & wmask]) > limit
1461 && --chain_length != 0);
1463 if ((uInt)best_len <= s->lookahead) return best_len;
1464 return s->lookahead;
1469 /* ===========================================================================
1470 * Check that the match at match_start is indeed a match.
1472 local void check_match(s, start, match, length)
1477 /* check that the match is indeed a match */
1478 if (zmemcmp((charf *)s->window + match,
1479 (charf *)s->window + start, length) != EQUAL) {
1480 fprintf(stderr, " start %u, match %u, length %d\n",
1481 start, match, length);
1483 fprintf(stderr, "%c%c", s->window[match++], s->window[start++]);
1484 } while (--length != 0);
1485 z_error("invalid match");
1487 if (z_verbose > 1) {
1488 fprintf(stderr,"\\[%d,%d]", start-match, length);
1489 do { putc(s->window[start++], stderr); } while (--length != 0);
1493 # define check_match(s, start, match, length)
1496 /* ===========================================================================
1497 * Fill the window when the lookahead becomes insufficient.
1498 * Updates strstart and lookahead.
1500 * IN assertion: lookahead < MIN_LOOKAHEAD
1501 * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD
1502 * At least one byte has been read, or avail_in == 0; reads are
1503 * performed for at least two bytes (required for the zip translate_eol
1504 * option -- not supported here).
1506 local void fill_window(s)
1509 register unsigned n, m;
1511 unsigned more; /* Amount of free space at the end of the window. */
1512 uInt wsize = s->w_size;
1515 more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart);
1517 /* Deal with !@#$% 64K limit: */
1518 if (more == 0 && s->strstart == 0 && s->lookahead == 0) {
1521 } else if (more == (unsigned)(-1)) {
1522 /* Very unlikely, but possible on 16 bit machine if strstart == 0
1523 * and lookahead == 1 (input done one byte at time)
1527 /* If the window is almost full and there is insufficient lookahead,
1528 * move the upper half to the lower one to make room in the upper half.
1530 } else if (s->strstart >= wsize+MAX_DIST(s)) {
1532 zmemcpy((charf *)s->window, (charf *)s->window+wsize,
1534 s->match_start -= wsize;
1535 s->strstart -= wsize; /* we now have strstart >= MAX_DIST */
1536 s->block_start -= (long) wsize;
1538 /* Slide the hash table (could be avoided with 32 bit values
1539 at the expense of memory usage). We slide even when level == 0
1540 to keep the hash table consistent if we switch back to level > 0
1541 later. (Using level 0 permanently is not an optimal usage of
1542 zlib, so we don't care about this pathological case.)
1548 *p = (Pos)(m >= wsize ? m-wsize : NIL);
1555 *p = (Pos)(m >= wsize ? m-wsize : NIL);
1556 /* If n is not on any hash chain, prev[n] is garbage but
1557 * its value will never be used.
1562 if (s->strm->avail_in == 0) return;
1564 /* If there was no sliding:
1565 * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 &&
1566 * more == window_size - lookahead - strstart
1567 * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1)
1568 * => more >= window_size - 2*WSIZE + 2
1569 * In the BIG_MEM or MMAP case (not yet supported),
1570 * window_size == input_size + MIN_LOOKAHEAD &&
1571 * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD.
1572 * Otherwise, window_size == 2*WSIZE so more >= 2.
1573 * If there was sliding, more >= WSIZE. So in all cases, more >= 2.
1575 Assert(more >= 2, "more < 2");
1577 n = read_buf(s->strm, (charf *)s->window + s->strstart + s->lookahead,
1581 /* Initialize the hash value now that we have some input: */
1582 if (s->lookahead >= MIN_MATCH) {
1583 s->ins_h = s->window[s->strstart];
1584 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
1586 Call UPDATE_HASH() MIN_MATCH-3 more times
1589 /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage,
1590 * but this is not important since only literal bytes will be emitted.
1593 } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0);
1596 /* ===========================================================================
1597 * Flush the current block, with given end-of-file flag.
1598 * IN assertion: strstart is set to the end of the current match.
1600 #define FLUSH_BLOCK_ONLY(s, eof) { \
1601 _tr_flush_block(s, (s->block_start >= 0L ? \
1602 (charf *)&s->window[(unsigned)s->block_start] : \
1604 (ulg)((long)s->strstart - s->block_start), \
1606 s->block_start = s->strstart; \
1607 flush_pending(s->strm); \
1608 Tracev((stderr,"[FLUSH]")); \
1611 /* Same but force premature exit if necessary. */
1612 #define FLUSH_BLOCK(s, eof) { \
1613 FLUSH_BLOCK_ONLY(s, eof); \
1614 if (s->strm->avail_out == 0) return (eof) ? finish_started : need_more; \
1617 /* ===========================================================================
1618 * Copy without compression as much as possible from the input stream, return
1619 * the current block state.
1620 * This function does not insert new strings in the dictionary since
1621 * uncompressible data is probably not useful. This function is used
1622 * only for the level=0 compression option.
1623 * NOTE: this function should be optimized to avoid extra copying from
1624 * window to pending_buf.
1626 local block_state deflate_stored(s, flush)
1630 /* Stored blocks are limited to 0xffff bytes, pending_buf is limited
1631 * to pending_buf_size, and each stored block has a 5 byte header:
1633 ulg max_block_size = 0xffff;
1636 if (max_block_size > s->pending_buf_size - 5) {
1637 max_block_size = s->pending_buf_size - 5;
1640 /* Copy as much as possible from input to output: */
1642 /* Fill the window as much as possible: */
1643 if (s->lookahead <= 1) {
1645 Assert(s->strstart < s->w_size+MAX_DIST(s) ||
1646 s->block_start >= (long)s->w_size, "slide too late");
1649 if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more;
1651 if (s->lookahead == 0) break; /* flush the current block */
1653 Assert(s->block_start >= 0L, "block gone");
1655 s->strstart += s->lookahead;
1658 /* Emit a stored block if pending_buf will be full: */
1659 max_start = s->block_start + max_block_size;
1660 if (s->strstart == 0 || (ulg)s->strstart >= max_start) {
1661 /* strstart == 0 is possible when wraparound on 16-bit machine */
1662 s->lookahead = (uInt)(s->strstart - max_start);
1663 s->strstart = (uInt)max_start;
1666 /* Flush if we may have to slide, otherwise block_start may become
1667 * negative and the data will be gone:
1669 if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) {
1673 FLUSH_BLOCK(s, flush == Z_FINISH);
1674 return flush == Z_FINISH ? finish_done : block_done;
1677 /* ===========================================================================
1678 * Compress as much as possible from the input stream, return the current
1680 * This function does not perform lazy evaluation of matches and inserts
1681 * new strings in the dictionary only for unmatched strings or for short
1682 * matches. It is used only for the fast compression options.
1684 local block_state deflate_fast(s, flush)
1688 IPos hash_head = NIL; /* head of the hash chain */
1689 int bflush; /* set if current block must be flushed */
1692 /* Make sure that we always have enough lookahead, except
1693 * at the end of the input file. We need MAX_MATCH bytes
1694 * for the next match, plus MIN_MATCH bytes to insert the
1695 * string following the next match.
1697 if (s->lookahead < MIN_LOOKAHEAD) {
1699 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
1702 if (s->lookahead == 0) break; /* flush the current block */
1705 /* Insert the string window[strstart .. strstart+2] in the
1706 * dictionary, and set hash_head to the head of the hash chain:
1708 if (s->lookahead >= MIN_MATCH) {
1709 INSERT_STRING(s, s->strstart, hash_head);
1712 /* Find the longest match, discarding those <= prev_length.
1713 * At this point we have always match_length < MIN_MATCH
1715 if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) {
1716 /* To simplify the code, we prevent matches with the string
1717 * of window index 0 (in particular we have to avoid a match
1718 * of the string with itself at the start of the input file).
1720 if (s->strategy != Z_HUFFMAN_ONLY) {
1721 s->match_length = longest_match (s, hash_head);
1723 /* longest_match() sets match_start */
1725 if (s->match_length >= MIN_MATCH) {
1726 check_match(s, s->strstart, s->match_start, s->match_length);
1728 bflush = _tr_tally(s, s->strstart - s->match_start,
1729 s->match_length - MIN_MATCH);
1731 s->lookahead -= s->match_length;
1733 /* Insert new strings in the hash table only if the match length
1734 * is not too large. This saves time but degrades compression.
1736 if (s->match_length <= s->max_insert_length &&
1737 s->lookahead >= MIN_MATCH) {
1738 s->match_length--; /* string at strstart already in hash table */
1741 INSERT_STRING(s, s->strstart, hash_head);
1742 /* strstart never exceeds WSIZE-MAX_MATCH, so there are
1743 * always MIN_MATCH bytes ahead.
1745 } while (--s->match_length != 0);
1748 s->strstart += s->match_length;
1749 s->match_length = 0;
1750 s->ins_h = s->window[s->strstart];
1751 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
1753 Call UPDATE_HASH() MIN_MATCH-3 more times
1755 /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not
1756 * matter since it will be recomputed at next deflate call.
1760 /* No match, output a literal byte */
1761 Tracevv((stderr,"%c", s->window[s->strstart]));
1762 bflush = _tr_tally (s, 0, s->window[s->strstart]);
1766 if (bflush) FLUSH_BLOCK(s, 0);
1768 FLUSH_BLOCK(s, flush == Z_FINISH);
1769 return flush == Z_FINISH ? finish_done : block_done;
1772 /* ===========================================================================
1773 * Same as above, but achieves better compression. We use a lazy
1774 * evaluation for matches: a match is finally adopted only if there is
1775 * no better match at the next window position.
1777 local block_state deflate_slow(s, flush)
1781 IPos hash_head = NIL; /* head of hash chain */
1782 int bflush; /* set if current block must be flushed */
1784 /* Process the input block. */
1786 /* Make sure that we always have enough lookahead, except
1787 * at the end of the input file. We need MAX_MATCH bytes
1788 * for the next match, plus MIN_MATCH bytes to insert the
1789 * string following the next match.
1791 if (s->lookahead < MIN_LOOKAHEAD) {
1793 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
1796 if (s->lookahead == 0) break; /* flush the current block */
1799 /* Insert the string window[strstart .. strstart+2] in the
1800 * dictionary, and set hash_head to the head of the hash chain:
1802 if (s->lookahead >= MIN_MATCH) {
1803 INSERT_STRING(s, s->strstart, hash_head);
1806 /* Find the longest match, discarding those <= prev_length.
1808 s->prev_length = s->match_length, s->prev_match = s->match_start;
1809 s->match_length = MIN_MATCH-1;
1811 if (hash_head != NIL && s->prev_length < s->max_lazy_match &&
1812 s->strstart - hash_head <= MAX_DIST(s)) {
1813 /* To simplify the code, we prevent matches with the string
1814 * of window index 0 (in particular we have to avoid a match
1815 * of the string with itself at the start of the input file).
1817 if (s->strategy != Z_HUFFMAN_ONLY) {
1818 s->match_length = longest_match (s, hash_head);
1820 /* longest_match() sets match_start */
1822 if (s->match_length <= 5 && (s->strategy == Z_FILTERED ||
1823 (s->match_length == MIN_MATCH &&
1824 s->strstart - s->match_start > TOO_FAR))) {
1826 /* If prev_match is also MIN_MATCH, match_start is garbage
1827 * but we will ignore the current match anyway.
1829 s->match_length = MIN_MATCH-1;
1832 /* If there was a match at the previous step and the current
1833 * match is not better, output the previous match:
1835 if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) {
1836 uInt max_insert = s->strstart + s->lookahead - MIN_MATCH;
1837 /* Do not insert strings in hash table beyond this. */
1839 check_match(s, s->strstart-1, s->prev_match, s->prev_length);
1841 bflush = _tr_tally(s, s->strstart -1 - s->prev_match,
1842 s->prev_length - MIN_MATCH);
1844 /* Insert in hash table all strings up to the end of the match.
1845 * strstart-1 and strstart are already inserted. If there is not
1846 * enough lookahead, the last two strings are not inserted in
1849 s->lookahead -= s->prev_length-1;
1850 s->prev_length -= 2;
1852 if (++s->strstart <= max_insert) {
1853 INSERT_STRING(s, s->strstart, hash_head);
1855 } while (--s->prev_length != 0);
1856 s->match_available = 0;
1857 s->match_length = MIN_MATCH-1;
1860 if (bflush) FLUSH_BLOCK(s, 0);
1862 } else if (s->match_available) {
1863 /* If there was no match at the previous position, output a
1864 * single literal. If there was a match but the current match
1865 * is longer, truncate the previous match to a single literal.
1867 Tracevv((stderr,"%c", s->window[s->strstart-1]));
1868 if (_tr_tally (s, 0, s->window[s->strstart-1])) {
1869 FLUSH_BLOCK_ONLY(s, 0);
1873 if (s->strm->avail_out == 0) return need_more;
1875 /* There is no previous match to compare with, wait for
1876 * the next step to decide.
1878 s->match_available = 1;
1883 Assert (flush != Z_NO_FLUSH, "no flush?");
1884 if (s->match_available) {
1885 Tracevv((stderr,"%c", s->window[s->strstart-1]));
1886 _tr_tally (s, 0, s->window[s->strstart-1]);
1887 s->match_available = 0;
1889 FLUSH_BLOCK(s, flush == Z_FINISH);
1890 return flush == Z_FINISH ? finish_done : block_done;
1895 /* trees.c -- output deflated data using Huffman coding
1896 * Copyright (C) 1995-1996 Jean-loup Gailly
1897 * For conditions of distribution and use, see copyright notice in zlib.h
1903 * The "deflation" process uses several Huffman trees. The more
1904 * common source values are represented by shorter bit sequences.
1906 * Each code tree is stored in a compressed form which is itself
1907 * a Huffman encoding of the lengths of all the code strings (in
1908 * ascending order by source values). The actual code strings are
1909 * reconstructed from the lengths in the inflate process, as described
1910 * in the deflate specification.
1914 * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification".
1915 * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc
1918 * Data Compression: Methods and Theory, pp. 49-50.
1919 * Computer Science Press, 1988. ISBN 0-7167-8156-5.
1923 * Addison-Wesley, 1983. ISBN 0-201-06672-6.
1926 /* From: trees.c,v 1.11 1996/07/24 13:41:06 me Exp $ */
1928 /* #include "deflate.h" */
1934 /* ===========================================================================
1938 #define MAX_BL_BITS 7
1939 /* Bit length codes must not exceed MAX_BL_BITS bits */
1941 #define END_BLOCK 256
1942 /* end of block literal code */
1945 /* repeat previous bit length 3-6 times (2 bits of repeat count) */
1947 #define REPZ_3_10 17
1948 /* repeat a zero length 3-10 times (3 bits of repeat count) */
1950 #define REPZ_11_138 18
1951 /* repeat a zero length 11-138 times (7 bits of repeat count) */
1953 local int extra_lbits[LENGTH_CODES] /* extra bits for each length code */
1954 = {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};
1956 local int extra_dbits[D_CODES] /* extra bits for each distance code */
1957 = {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};
1959 local int extra_blbits[BL_CODES]/* extra bits for each bit length code */
1960 = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};
1962 local uch bl_order[BL_CODES]
1963 = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};
1964 /* The lengths of the bit length codes are sent in order of decreasing
1965 * probability, to avoid transmitting the lengths for unused bit length codes.
1968 #define Buf_size (8 * 2*sizeof(char))
1969 /* Number of bits used within bi_buf. (bi_buf might be implemented on
1970 * more than 16 bits on some systems.)
1973 /* ===========================================================================
1974 * Local data. These are initialized only once.
1977 local ct_data static_ltree[L_CODES+2];
1978 /* The static literal tree. Since the bit lengths are imposed, there is no
1979 * need for the L_CODES extra codes used during heap construction. However
1980 * The codes 286 and 287 are needed to build a canonical tree (see _tr_init
1984 local ct_data static_dtree[D_CODES];
1985 /* The static distance tree. (Actually a trivial tree since all codes use
1989 local uch dist_code[512];
1990 /* distance codes. The first 256 values correspond to the distances
1991 * 3 .. 258, the last 256 values correspond to the top 8 bits of
1992 * the 15 bit distances.
1995 local uch length_code[MAX_MATCH-MIN_MATCH+1];
1996 /* length code for each normalized match length (0 == MIN_MATCH) */
1998 local int base_length[LENGTH_CODES];
1999 /* First normalized length for each code (0 = MIN_MATCH) */
2001 local int base_dist[D_CODES];
2002 /* First normalized distance for each code (0 = distance of 1) */
2004 struct static_tree_desc_s {
2005 ct_data *static_tree; /* static tree or NULL */
2006 intf *extra_bits; /* extra bits for each code or NULL */
2007 int extra_base; /* base index for extra_bits */
2008 int elems; /* max number of elements in the tree */
2009 int max_length; /* max bit length for the codes */
2012 local static_tree_desc static_l_desc =
2013 {static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS};
2015 local static_tree_desc static_d_desc =
2016 {static_dtree, extra_dbits, 0, D_CODES, MAX_BITS};
2018 local static_tree_desc static_bl_desc =
2019 {(ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS};
2021 /* ===========================================================================
2022 * Local (static) routines in this file.
2025 local void tr_static_init OF((void));
2026 local void init_block OF((deflate_state *s));
2027 local void pqdownheap OF((deflate_state *s, ct_data *tree, int k));
2028 local void gen_bitlen OF((deflate_state *s, tree_desc *desc));
2029 local void gen_codes OF((ct_data *tree, int max_code, ushf *bl_count));
2030 local void build_tree OF((deflate_state *s, tree_desc *desc));
2031 local void scan_tree OF((deflate_state *s, ct_data *tree, int max_code));
2032 local void send_tree OF((deflate_state *s, ct_data *tree, int max_code));
2033 local int build_bl_tree OF((deflate_state *s));
2034 local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes,
2036 local void compress_block OF((deflate_state *s, ct_data *ltree,
2038 local void set_data_type OF((deflate_state *s));
2039 local unsigned bi_reverse OF((unsigned value, int length));
2040 local void bi_windup OF((deflate_state *s));
2041 local void bi_flush OF((deflate_state *s));
2042 local void copy_block OF((deflate_state *s, charf *buf, unsigned len,
2046 # define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len)
2047 /* Send a code of the given tree. c and tree must not have side effects */
2049 #else /* DEBUG_ZLIB */
2050 # define send_code(s, c, tree) \
2051 { if (verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \
2052 send_bits(s, tree[c].Code, tree[c].Len); }
2055 #define d_code(dist) \
2056 ((dist) < 256 ? dist_code[dist] : dist_code[256+((dist)>>7)])
2057 /* Mapping from a distance to a distance code. dist is the distance - 1 and
2058 * must not have side effects. dist_code[256] and dist_code[257] are never
2062 /* ===========================================================================
2063 * Output a short LSB first on the stream.
2064 * IN assertion: there is enough room in pendingBuf.
2066 #define put_short(s, w) { \
2067 put_byte(s, (uch)((w) & 0xff)); \
2068 put_byte(s, (uch)((ush)(w) >> 8)); \
2071 /* ===========================================================================
2072 * Send a value on a given number of bits.
2073 * IN assertion: length <= 16 and value fits in length bits.
2076 local void send_bits OF((deflate_state *s, int value, int length));
2078 local void send_bits(s, value, length)
2080 int value; /* value to send */
2081 int length; /* number of bits */
2083 Tracevv((stderr," l %2d v %4x ", length, value));
2084 Assert(length > 0 && length <= 15, "invalid length");
2085 s->bits_sent += (ulg)length;
2087 /* If not enough room in bi_buf, use (valid) bits from bi_buf and
2088 * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
2089 * unused bits in value.
2091 if (s->bi_valid > (int)Buf_size - length) {
2092 s->bi_buf |= (value << s->bi_valid);
2093 put_short(s, s->bi_buf);
2094 s->bi_buf = (ush)value >> (Buf_size - s->bi_valid);
2095 s->bi_valid += length - Buf_size;
2097 s->bi_buf |= value << s->bi_valid;
2098 s->bi_valid += length;
2101 #else /* !DEBUG_ZLIB */
2103 #define send_bits(s, value, length) \
2104 { int len = length;\
2105 if (s->bi_valid > (int)Buf_size - len) {\
2107 s->bi_buf |= (val << s->bi_valid);\
2108 put_short(s, s->bi_buf);\
2109 s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\
2110 s->bi_valid += len - Buf_size;\
2112 s->bi_buf |= (value) << s->bi_valid;\
2113 s->bi_valid += len;\
2116 #endif /* DEBUG_ZLIB */
2119 #define MAX(a,b) (a >= b ? a : b)
2120 /* the arguments must not have side effects */
2122 /* ===========================================================================
2123 * Initialize the various 'constant' tables. In a multi-threaded environment,
2124 * this function may be called by two threads concurrently, but this is
2125 * harmless since both invocations do exactly the same thing.
2127 local void tr_static_init()
2129 static int static_init_done = 0;
2130 int n; /* iterates over tree elements */
2131 int bits; /* bit counter */
2132 int length; /* length value */
2133 int code; /* code value */
2134 int dist; /* distance index */
2135 ush bl_count[MAX_BITS+1];
2136 /* number of codes at each bit length for an optimal tree */
2138 if (static_init_done) return;
2140 /* Initialize the mapping length (0..255) -> length code (0..28) */
2142 for (code = 0; code < LENGTH_CODES-1; code++) {
2143 base_length[code] = length;
2144 for (n = 0; n < (1<<extra_lbits[code]); n++) {
2145 length_code[length++] = (uch)code;
2148 Assert (length == 256, "tr_static_init: length != 256");
2149 /* Note that the length 255 (match length 258) can be represented
2150 * in two different ways: code 284 + 5 bits or code 285, so we
2151 * overwrite length_code[255] to use the best encoding:
2153 length_code[length-1] = (uch)code;
2155 /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
2157 for (code = 0 ; code < 16; code++) {
2158 base_dist[code] = dist;
2159 for (n = 0; n < (1<<extra_dbits[code]); n++) {
2160 dist_code[dist++] = (uch)code;
2163 Assert (dist == 256, "tr_static_init: dist != 256");
2164 dist >>= 7; /* from now on, all distances are divided by 128 */
2165 for ( ; code < D_CODES; code++) {
2166 base_dist[code] = dist << 7;
2167 for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
2168 dist_code[256 + dist++] = (uch)code;
2171 Assert (dist == 256, "tr_static_init: 256+dist != 512");
2173 /* Construct the codes of the static literal tree */
2174 for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
2176 while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;
2177 while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;
2178 while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;
2179 while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;
2180 /* Codes 286 and 287 do not exist, but we must include them in the
2181 * tree construction to get a canonical Huffman tree (longest code
2184 gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count);
2186 /* The static distance tree is trivial: */
2187 for (n = 0; n < D_CODES; n++) {
2188 static_dtree[n].Len = 5;
2189 static_dtree[n].Code = bi_reverse((unsigned)n, 5);
2191 static_init_done = 1;
2194 /* ===========================================================================
2195 * Initialize the tree data structures for a new zlib stream.
2202 s->compressed_len = 0L;
2204 s->l_desc.dyn_tree = s->dyn_ltree;
2205 s->l_desc.stat_desc = &static_l_desc;
2207 s->d_desc.dyn_tree = s->dyn_dtree;
2208 s->d_desc.stat_desc = &static_d_desc;
2210 s->bl_desc.dyn_tree = s->bl_tree;
2211 s->bl_desc.stat_desc = &static_bl_desc;
2215 s->last_eob_len = 8; /* enough lookahead for inflate */
2220 /* Initialize the first block of the first file: */
2224 /* ===========================================================================
2225 * Initialize a new block.
2227 local void init_block(s)
2230 int n; /* iterates over tree elements */
2232 /* Initialize the trees. */
2233 for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0;
2234 for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0;
2235 for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
2237 s->dyn_ltree[END_BLOCK].Freq = 1;
2238 s->opt_len = s->static_len = 0L;
2239 s->last_lit = s->matches = 0;
2243 /* Index within the heap array of least frequent node in the Huffman tree */
2246 /* ===========================================================================
2247 * Remove the smallest element from the heap and recreate the heap with
2248 * one less element. Updates heap and heap_len.
2250 #define pqremove(s, tree, top) \
2252 top = s->heap[SMALLEST]; \
2253 s->heap[SMALLEST] = s->heap[s->heap_len--]; \
2254 pqdownheap(s, tree, SMALLEST); \
2257 /* ===========================================================================
2258 * Compares to subtrees, using the tree depth as tie breaker when
2259 * the subtrees have equal frequency. This minimizes the worst case length.
2261 #define smaller(tree, n, m, depth) \
2262 (tree[n].Freq < tree[m].Freq || \
2263 (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m]))
2265 /* ===========================================================================
2266 * Restore the heap property by moving down the tree starting at node k,
2267 * exchanging a node with the smallest of its two sons if necessary, stopping
2268 * when the heap property is re-established (each father smaller than its
2271 local void pqdownheap(s, tree, k)
2273 ct_data *tree; /* the tree to restore */
2274 int k; /* node to move down */
2277 int j = k << 1; /* left son of k */
2278 while (j <= s->heap_len) {
2279 /* Set j to the smallest of the two sons: */
2280 if (j < s->heap_len &&
2281 smaller(tree, s->heap[j+1], s->heap[j], s->depth)) {
2284 /* Exit if v is smaller than both sons */
2285 if (smaller(tree, v, s->heap[j], s->depth)) break;
2287 /* Exchange v with the smallest son */
2288 s->heap[k] = s->heap[j]; k = j;
2290 /* And continue down the tree, setting j to the left son of k */
2296 /* ===========================================================================
2297 * Compute the optimal bit lengths for a tree and update the total bit length
2298 * for the current block.
2299 * IN assertion: the fields freq and dad are set, heap[heap_max] and
2300 * above are the tree nodes sorted by increasing frequency.
2301 * OUT assertions: the field len is set to the optimal bit length, the
2302 * array bl_count contains the frequencies for each bit length.
2303 * The length opt_len is updated; static_len is also updated if stree is
2306 local void gen_bitlen(s, desc)
2308 tree_desc *desc; /* the tree descriptor */
2310 ct_data *tree = desc->dyn_tree;
2311 int max_code = desc->max_code;
2312 ct_data *stree = desc->stat_desc->static_tree;
2313 intf *extra = desc->stat_desc->extra_bits;
2314 int base = desc->stat_desc->extra_base;
2315 int max_length = desc->stat_desc->max_length;
2316 int h; /* heap index */
2317 int n, m; /* iterate over the tree elements */
2318 int bits; /* bit length */
2319 int xbits; /* extra bits */
2320 ush f; /* frequency */
2321 int overflow = 0; /* number of elements with bit length too large */
2323 for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0;
2325 /* In a first pass, compute the optimal bit lengths (which may
2326 * overflow in the case of the bit length tree).
2328 tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */
2330 for (h = s->heap_max+1; h < HEAP_SIZE; h++) {
2332 bits = tree[tree[n].Dad].Len + 1;
2333 if (bits > max_length) bits = max_length, overflow++;
2334 tree[n].Len = (ush)bits;
2335 /* We overwrite tree[n].Dad which is no longer needed */
2337 if (n > max_code) continue; /* not a leaf node */
2339 s->bl_count[bits]++;
2341 if (n >= base) xbits = extra[n-base];
2343 s->opt_len += (ulg)f * (bits + xbits);
2344 if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits);
2346 if (overflow == 0) return;
2348 Trace((stderr,"\nbit length overflow\n"));
2349 /* This happens for example on obj2 and pic of the Calgary corpus */
2351 /* Find the first bit length which could increase: */
2353 bits = max_length-1;
2354 while (s->bl_count[bits] == 0) bits--;
2355 s->bl_count[bits]--; /* move one leaf down the tree */
2356 s->bl_count[bits+1] += 2; /* move one overflow item as its brother */
2357 s->bl_count[max_length]--;
2358 /* The brother of the overflow item also moves one step up,
2359 * but this does not affect bl_count[max_length]
2362 } while (overflow > 0);
2364 /* Now recompute all bit lengths, scanning in increasing frequency.
2365 * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
2366 * lengths instead of fixing only the wrong ones. This idea is taken
2367 * from 'ar' written by Haruhiko Okumura.)
2369 for (bits = max_length; bits != 0; bits--) {
2370 n = s->bl_count[bits];
2373 if (m > max_code) continue;
2374 if (tree[m].Len != (unsigned) bits) {
2375 Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits));
2376 s->opt_len += ((long)bits - (long)tree[m].Len)
2377 *(long)tree[m].Freq;
2378 tree[m].Len = (ush)bits;
2385 /* ===========================================================================
2386 * Generate the codes for a given tree and bit counts (which need not be
2388 * IN assertion: the array bl_count contains the bit length statistics for
2389 * the given tree and the field len is set for all tree elements.
2390 * OUT assertion: the field code is set for all tree elements of non
2393 local void gen_codes (tree, max_code, bl_count)
2394 ct_data *tree; /* the tree to decorate */
2395 int max_code; /* largest code with non zero frequency */
2396 ushf *bl_count; /* number of codes at each bit length */
2398 ush next_code[MAX_BITS+1]; /* next code value for each bit length */
2399 ush code = 0; /* running code value */
2400 int bits; /* bit index */
2401 int n; /* code index */
2403 /* The distribution counts are first used to generate the code values
2404 * without bit reversal.
2406 for (bits = 1; bits <= MAX_BITS; bits++) {
2407 next_code[bits] = code = (code + bl_count[bits-1]) << 1;
2409 /* Check that the bit counts in bl_count are consistent. The last code
2412 Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
2413 "inconsistent bit counts");
2414 Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
2416 for (n = 0; n <= max_code; n++) {
2417 int len = tree[n].Len;
2418 if (len == 0) continue;
2419 /* Now reverse the bits */
2420 tree[n].Code = bi_reverse(next_code[len]++, len);
2422 Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
2423 n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
2427 /* ===========================================================================
2428 * Construct one Huffman tree and assigns the code bit strings and lengths.
2429 * Update the total bit length for the current block.
2430 * IN assertion: the field freq is set for all tree elements.
2431 * OUT assertions: the fields len and code are set to the optimal bit length
2432 * and corresponding code. The length opt_len is updated; static_len is
2433 * also updated if stree is not null. The field max_code is set.
2435 local void build_tree(s, desc)
2437 tree_desc *desc; /* the tree descriptor */
2439 ct_data *tree = desc->dyn_tree;
2440 ct_data *stree = desc->stat_desc->static_tree;
2441 int elems = desc->stat_desc->elems;
2442 int n, m; /* iterate over heap elements */
2443 int max_code = -1; /* largest code with non zero frequency */
2444 int node; /* new node being created */
2446 /* Construct the initial heap, with least frequent element in
2447 * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
2448 * heap[0] is not used.
2450 s->heap_len = 0, s->heap_max = HEAP_SIZE;
2452 for (n = 0; n < elems; n++) {
2453 if (tree[n].Freq != 0) {
2454 s->heap[++(s->heap_len)] = max_code = n;
2461 /* The pkzip format requires that at least one distance code exists,
2462 * and that at least one bit should be sent even if there is only one
2463 * possible code. So to avoid special checks later on we force at least
2464 * two codes of non zero frequency.
2466 while (s->heap_len < 2) {
2467 node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0);
2468 tree[node].Freq = 1;
2470 s->opt_len--; if (stree) s->static_len -= stree[node].Len;
2471 /* node is 0 or 1 so it does not have extra bits */
2473 desc->max_code = max_code;
2475 /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
2476 * establish sub-heaps of increasing lengths:
2478 for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n);
2480 /* Construct the Huffman tree by repeatedly combining the least two
2483 node = elems; /* next internal node of the tree */
2485 pqremove(s, tree, n); /* n = node of least frequency */
2486 m = s->heap[SMALLEST]; /* m = node of next least frequency */
2488 s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */
2489 s->heap[--(s->heap_max)] = m;
2491 /* Create a new node father of n and m */
2492 tree[node].Freq = tree[n].Freq + tree[m].Freq;
2493 s->depth[node] = (uch) (MAX(s->depth[n], s->depth[m]) + 1);
2494 tree[n].Dad = tree[m].Dad = (ush)node;
2496 if (tree == s->bl_tree) {
2497 fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)",
2498 node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq);
2501 /* and insert the new node in the heap */
2502 s->heap[SMALLEST] = node++;
2503 pqdownheap(s, tree, SMALLEST);
2505 } while (s->heap_len >= 2);
2507 s->heap[--(s->heap_max)] = s->heap[SMALLEST];
2509 /* At this point, the fields freq and dad are set. We can now
2510 * generate the bit lengths.
2512 gen_bitlen(s, (tree_desc *)desc);
2514 /* The field len is now set, we can generate the bit codes */
2515 gen_codes ((ct_data *)tree, max_code, s->bl_count);
2518 /* ===========================================================================
2519 * Scan a literal or distance tree to determine the frequencies of the codes
2520 * in the bit length tree.
2522 local void scan_tree (s, tree, max_code)
2524 ct_data *tree; /* the tree to be scanned */
2525 int max_code; /* and its largest code of non zero frequency */
2527 int n; /* iterates over all tree elements */
2528 int prevlen = -1; /* last emitted length */
2529 int curlen; /* length of current code */
2530 int nextlen = tree[0].Len; /* length of next code */
2531 int count = 0; /* repeat count of the current code */
2532 int max_count = 7; /* max repeat count */
2533 int min_count = 4; /* min repeat count */
2535 if (nextlen == 0) max_count = 138, min_count = 3;
2536 tree[max_code+1].Len = (ush)0xffff; /* guard */
2538 for (n = 0; n <= max_code; n++) {
2539 curlen = nextlen; nextlen = tree[n+1].Len;
2540 if (++count < max_count && curlen == nextlen) {
2542 } else if (count < min_count) {
2543 s->bl_tree[curlen].Freq += count;
2544 } else if (curlen != 0) {
2545 if (curlen != prevlen) s->bl_tree[curlen].Freq++;
2546 s->bl_tree[REP_3_6].Freq++;
2547 } else if (count <= 10) {
2548 s->bl_tree[REPZ_3_10].Freq++;
2550 s->bl_tree[REPZ_11_138].Freq++;
2552 count = 0; prevlen = curlen;
2554 max_count = 138, min_count = 3;
2555 } else if (curlen == nextlen) {
2556 max_count = 6, min_count = 3;
2558 max_count = 7, min_count = 4;
2563 /* ===========================================================================
2564 * Send a literal or distance tree in compressed form, using the codes in
2567 local void send_tree (s, tree, max_code)
2569 ct_data *tree; /* the tree to be scanned */
2570 int max_code; /* and its largest code of non zero frequency */
2572 int n; /* iterates over all tree elements */
2573 int prevlen = -1; /* last emitted length */
2574 int curlen; /* length of current code */
2575 int nextlen = tree[0].Len; /* length of next code */
2576 int count = 0; /* repeat count of the current code */
2577 int max_count = 7; /* max repeat count */
2578 int min_count = 4; /* min repeat count */
2580 /* tree[max_code+1].Len = -1; */ /* guard already set */
2581 if (nextlen == 0) max_count = 138, min_count = 3;
2583 for (n = 0; n <= max_code; n++) {
2584 curlen = nextlen; nextlen = tree[n+1].Len;
2585 if (++count < max_count && curlen == nextlen) {
2587 } else if (count < min_count) {
2588 do { send_code(s, curlen, s->bl_tree); } while (--count != 0);
2590 } else if (curlen != 0) {
2591 if (curlen != prevlen) {
2592 send_code(s, curlen, s->bl_tree); count--;
2594 Assert(count >= 3 && count <= 6, " 3_6?");
2595 send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2);
2597 } else if (count <= 10) {
2598 send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3);
2601 send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7);
2603 count = 0; prevlen = curlen;
2605 max_count = 138, min_count = 3;
2606 } else if (curlen == nextlen) {
2607 max_count = 6, min_count = 3;
2609 max_count = 7, min_count = 4;
2614 /* ===========================================================================
2615 * Construct the Huffman tree for the bit lengths and return the index in
2616 * bl_order of the last bit length code to send.
2618 local int build_bl_tree(s)
2621 int max_blindex; /* index of last bit length code of non zero freq */
2623 /* Determine the bit length frequencies for literal and distance trees */
2624 scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code);
2625 scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code);
2627 /* Build the bit length tree: */
2628 build_tree(s, (tree_desc *)(&(s->bl_desc)));
2629 /* opt_len now includes the length of the tree representations, except
2630 * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
2633 /* Determine the number of bit length codes to send. The pkzip format
2634 * requires that at least 4 bit length codes be sent. (appnote.txt says
2635 * 3 but the actual value used is 4.)
2637 for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) {
2638 if (s->bl_tree[bl_order[max_blindex]].Len != 0) break;
2640 /* Update opt_len to include the bit length tree and counts */
2641 s->opt_len += 3*(max_blindex+1) + 5+5+4;
2642 Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
2643 s->opt_len, s->static_len));
2648 /* ===========================================================================
2649 * Send the header for a block using dynamic Huffman trees: the counts, the
2650 * lengths of the bit length codes, the literal tree and the distance tree.
2651 * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
2653 local void send_all_trees(s, lcodes, dcodes, blcodes)
2655 int lcodes, dcodes, blcodes; /* number of codes for each tree */
2657 int rank; /* index in bl_order */
2659 Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
2660 Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
2662 Tracev((stderr, "\nbl counts: "));
2663 send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */
2664 send_bits(s, dcodes-1, 5);
2665 send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */
2666 for (rank = 0; rank < blcodes; rank++) {
2667 Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
2668 send_bits(s, s->bl_tree[bl_order[rank]].Len, 3);
2670 Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent));
2672 send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */
2673 Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent));
2675 send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */
2676 Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent));
2679 /* ===========================================================================
2680 * Send a stored block
2682 void _tr_stored_block(s, buf, stored_len, eof)
2684 charf *buf; /* input block */
2685 ulg stored_len; /* length of input block */
2686 int eof; /* true if this is the last block for a file */
2688 send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */
2689 s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
2690 s->compressed_len += (stored_len + 4) << 3;
2692 copy_block(s, buf, (unsigned)stored_len, 1); /* with header */
2695 /* Send just the `stored block' type code without any length bytes or data.
2697 void _tr_stored_type_only(s)
2700 send_bits(s, (STORED_BLOCK << 1), 3);
2702 s->compressed_len = (s->compressed_len + 3) & ~7L;
2706 /* ===========================================================================
2707 * Send one empty static block to give enough lookahead for inflate.
2708 * This takes 10 bits, of which 7 may remain in the bit buffer.
2709 * The current inflate code requires 9 bits of lookahead. If the
2710 * last two codes for the previous block (real code plus EOB) were coded
2711 * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode
2712 * the last real code. In this case we send two empty static blocks instead
2713 * of one. (There are no problems if the previous block is stored or fixed.)
2714 * To simplify the code, we assume the worst case of last real code encoded
2720 send_bits(s, STATIC_TREES<<1, 3);
2721 send_code(s, END_BLOCK, static_ltree);
2722 s->compressed_len += 10L; /* 3 for block type, 7 for EOB */
2724 /* Of the 10 bits for the empty block, we have already sent
2725 * (10 - bi_valid) bits. The lookahead for the last real code (before
2726 * the EOB of the previous block) was thus at least one plus the length
2727 * of the EOB plus what we have just sent of the empty static block.
2729 if (1 + s->last_eob_len + 10 - s->bi_valid < 9) {
2730 send_bits(s, STATIC_TREES<<1, 3);
2731 send_code(s, END_BLOCK, static_ltree);
2732 s->compressed_len += 10L;
2735 s->last_eob_len = 7;
2738 /* ===========================================================================
2739 * Determine the best encoding for the current block: dynamic trees, static
2740 * trees or store, and output the encoded block to the zip file. This function
2741 * returns the total compressed length for the file so far.
2743 ulg _tr_flush_block(s, buf, stored_len, eof)
2745 charf *buf; /* input block, or NULL if too old */
2746 ulg stored_len; /* length of input block */
2747 int eof; /* true if this is the last block for a file */
2749 ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
2750 int max_blindex = 0; /* index of last bit length code of non zero freq */
2752 /* Build the Huffman trees unless a stored block is forced */
2755 /* Check if the file is ascii or binary */
2756 if (s->data_type == Z_UNKNOWN) set_data_type(s);
2758 /* Construct the literal and distance trees */
2759 build_tree(s, (tree_desc *)(&(s->l_desc)));
2760 Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len,
2763 build_tree(s, (tree_desc *)(&(s->d_desc)));
2764 Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len,
2766 /* At this point, opt_len and static_len are the total bit lengths of
2767 * the compressed block data, excluding the tree representations.
2770 /* Build the bit length tree for the above two trees, and get the index
2771 * in bl_order of the last bit length code to send.
2773 max_blindex = build_bl_tree(s);
2775 /* Determine the best encoding. Compute first the block length in bytes*/
2776 opt_lenb = (s->opt_len+3+7)>>3;
2777 static_lenb = (s->static_len+3+7)>>3;
2779 Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
2780 opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
2783 if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
2786 Assert(buf != (char*)0, "lost buf");
2787 opt_lenb = static_lenb = stored_len + 5; /* force a stored block */
2790 /* If compression failed and this is the first and last block,
2791 * and if the .zip file can be seeked (to rewrite the local header),
2792 * the whole file is transformed into a stored file:
2794 #ifdef STORED_FILE_OK
2795 # ifdef FORCE_STORED_FILE
2796 if (eof && s->compressed_len == 0L) { /* force stored file */
2798 if (stored_len <= opt_lenb && eof && s->compressed_len==0L && seekable()) {
2800 /* Since LIT_BUFSIZE <= 2*WSIZE, the input data must be there: */
2801 if (buf == (charf*)0) error ("block vanished");
2803 copy_block(s, buf, (unsigned)stored_len, 0); /* without header */
2804 s->compressed_len = stored_len << 3;
2807 #endif /* STORED_FILE_OK */
2810 if (buf != (char*)0) { /* force stored block */
2812 if (stored_len+4 <= opt_lenb && buf != (char*)0) {
2813 /* 4: two words for the lengths */
2815 /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
2816 * Otherwise we can't have processed more than WSIZE input bytes since
2817 * the last block flush, because compression would have been
2818 * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
2819 * transform a block into a stored block.
2821 _tr_stored_block(s, buf, stored_len, eof);
2824 } else if (static_lenb >= 0) { /* force static trees */
2826 } else if (static_lenb == opt_lenb) {
2828 send_bits(s, (STATIC_TREES<<1)+eof, 3);
2829 compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree);
2830 s->compressed_len += 3 + s->static_len;
2832 send_bits(s, (DYN_TREES<<1)+eof, 3);
2833 send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
2835 compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree);
2836 s->compressed_len += 3 + s->opt_len;
2838 Assert (s->compressed_len == s->bits_sent, "bad compressed size");
2843 s->compressed_len += 7; /* align on byte boundary */
2845 Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
2846 s->compressed_len-7*eof));
2848 return s->compressed_len >> 3;
2851 /* ===========================================================================
2852 * Save the match info and tally the frequency counts. Return true if
2853 * the current block must be flushed.
2855 int _tr_tally (s, dist, lc)
2857 unsigned dist; /* distance of matched string */
2858 unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */
2860 s->d_buf[s->last_lit] = (ush)dist;
2861 s->l_buf[s->last_lit++] = (uch)lc;
2863 /* lc is the unmatched char */
2864 s->dyn_ltree[lc].Freq++;
2867 /* Here, lc is the match length - MIN_MATCH */
2868 dist--; /* dist = match distance - 1 */
2869 Assert((ush)dist < (ush)MAX_DIST(s) &&
2870 (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
2871 (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match");
2873 s->dyn_ltree[length_code[lc]+LITERALS+1].Freq++;
2874 s->dyn_dtree[d_code(dist)].Freq++;
2877 /* Try to guess if it is profitable to stop the current block here */
2878 if (s->level > 2 && (s->last_lit & 0xfff) == 0) {
2879 /* Compute an upper bound for the compressed length */
2880 ulg out_length = (ulg)s->last_lit*8L;
2881 ulg in_length = (ulg)((long)s->strstart - s->block_start);
2883 for (dcode = 0; dcode < D_CODES; dcode++) {
2884 out_length += (ulg)s->dyn_dtree[dcode].Freq *
2885 (5L+extra_dbits[dcode]);
2888 Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ",
2889 s->last_lit, in_length, out_length,
2890 100L - out_length*100L/in_length));
2891 if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1;
2893 return (s->last_lit == s->lit_bufsize-1);
2894 /* We avoid equality with lit_bufsize because of wraparound at 64K
2895 * on 16 bit machines and because stored blocks are restricted to
2900 /* ===========================================================================
2901 * Send the block data compressed using the given Huffman trees
2903 local void compress_block(s, ltree, dtree)
2905 ct_data *ltree; /* literal tree */
2906 ct_data *dtree; /* distance tree */
2908 unsigned dist; /* distance of matched string */
2909 int lc; /* match length or unmatched char (if dist == 0) */
2910 unsigned lx = 0; /* running index in l_buf */
2911 unsigned code; /* the code to send */
2912 int extra; /* number of extra bits to send */
2914 if (s->last_lit != 0) do {
2915 dist = s->d_buf[lx];
2916 lc = s->l_buf[lx++];
2918 send_code(s, lc, ltree); /* send a literal byte */
2919 Tracecv(isgraph(lc), (stderr," '%c' ", lc));
2921 /* Here, lc is the match length - MIN_MATCH */
2922 code = length_code[lc];
2923 send_code(s, code+LITERALS+1, ltree); /* send the length code */
2924 extra = extra_lbits[code];
2926 lc -= base_length[code];
2927 send_bits(s, lc, extra); /* send the extra length bits */
2929 dist--; /* dist is now the match distance - 1 */
2930 code = d_code(dist);
2931 Assert (code < D_CODES, "bad d_code");
2933 send_code(s, code, dtree); /* send the distance code */
2934 extra = extra_dbits[code];
2936 dist -= base_dist[code];
2937 send_bits(s, dist, extra); /* send the extra distance bits */
2939 } /* literal or match pair ? */
2941 /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */
2942 Assert(s->pending < s->lit_bufsize + 2*lx, "pendingBuf overflow");
2944 } while (lx < s->last_lit);
2946 send_code(s, END_BLOCK, ltree);
2947 s->last_eob_len = ltree[END_BLOCK].Len;
2950 /* ===========================================================================
2951 * Set the data type to ASCII or BINARY, using a crude approximation:
2952 * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise.
2953 * IN assertion: the fields freq of dyn_ltree are set and the total of all
2954 * frequencies does not exceed 64K (to fit in an int on 16 bit machines).
2956 local void set_data_type(s)
2960 unsigned ascii_freq = 0;
2961 unsigned bin_freq = 0;
2962 while (n < 7) bin_freq += s->dyn_ltree[n++].Freq;
2963 while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq;
2964 while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq;
2965 s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? Z_BINARY : Z_ASCII);
2968 /* ===========================================================================
2969 * Reverse the first len bits of a code, using straightforward code (a faster
2970 * method would use a table)
2971 * IN assertion: 1 <= len <= 15
2973 local unsigned bi_reverse(code, len)
2974 unsigned code; /* the value to invert */
2975 int len; /* its bit length */
2977 register unsigned res = 0;
2980 code >>= 1, res <<= 1;
2981 } while (--len > 0);
2985 /* ===========================================================================
2986 * Flush the bit buffer, keeping at most 7 bits in it.
2988 local void bi_flush(s)
2991 if (s->bi_valid == 16) {
2992 put_short(s, s->bi_buf);
2995 } else if (s->bi_valid >= 8) {
2996 put_byte(s, (Byte)s->bi_buf);
3002 /* ===========================================================================
3003 * Flush the bit buffer and align the output on a byte boundary
3005 local void bi_windup(s)
3008 if (s->bi_valid > 8) {
3009 put_short(s, s->bi_buf);
3010 } else if (s->bi_valid > 0) {
3011 put_byte(s, (Byte)s->bi_buf);
3016 s->bits_sent = (s->bits_sent+7) & ~7;
3020 /* ===========================================================================
3021 * Copy a stored block, storing first the length and its
3022 * one's complement if requested.
3024 local void copy_block(s, buf, len, header)
3026 charf *buf; /* the input data */
3027 unsigned len; /* its length */
3028 int header; /* true if block header must be written */
3030 bi_windup(s); /* align on byte boundary */
3031 s->last_eob_len = 8; /* enough lookahead for inflate */
3034 put_short(s, (ush)len);
3035 put_short(s, (ush)~len);
3037 s->bits_sent += 2*16;
3041 s->bits_sent += (ulg)len<<3;
3043 /* bundle up the put_byte(s, *buf++) calls */
3044 zmemcpy(&s->pending_buf[s->pending], buf, len);
3050 /* inflate.c -- zlib interface to inflate modules
3051 * Copyright (C) 1995-1996 Mark Adler
3052 * For conditions of distribution and use, see copyright notice in zlib.h
3055 /* #include "zutil.h" */
3057 /* +++ infblock.h */
3058 /* infblock.h -- header to use infblock.c
3059 * Copyright (C) 1995-1996 Mark Adler
3060 * For conditions of distribution and use, see copyright notice in zlib.h
3063 /* WARNING: this file should *not* be used by applications. It is
3064 part of the implementation of the compression library and is
3065 subject to change. Applications should only use zlib.h.
3068 struct inflate_blocks_state;
3069 typedef struct inflate_blocks_state FAR inflate_blocks_statef;
3071 extern inflate_blocks_statef * inflate_blocks_new OF((
3073 check_func c, /* check function */
3074 uInt w)); /* window size */
3076 extern int inflate_blocks OF((
3077 inflate_blocks_statef *,
3079 int)); /* initial return code */
3081 extern void inflate_blocks_reset OF((
3082 inflate_blocks_statef *,
3084 uLongf *)); /* check value on output */
3086 extern int inflate_blocks_free OF((
3087 inflate_blocks_statef *,
3089 uLongf *)); /* check value on output */
3091 extern void inflate_set_dictionary OF((
3092 inflate_blocks_statef *s,
3093 const Bytef *d, /* dictionary */
3094 uInt n)); /* dictionary length */
3096 extern int inflate_addhistory OF((
3097 inflate_blocks_statef *,
3100 extern int inflate_packet_flush OF((
3101 inflate_blocks_statef *));
3102 /* --- infblock.h */
3104 #ifndef NO_DUMMY_DECL
3105 struct inflate_blocks_state {int dummy;}; /* for buggy compilers */
3108 /* inflate private state */
3109 struct internal_state {
3113 METHOD, /* waiting for method byte */
3114 FLAG, /* waiting for flag byte */
3115 DICT4, /* four dictionary check bytes to go */
3116 DICT3, /* three dictionary check bytes to go */
3117 DICT2, /* two dictionary check bytes to go */
3118 DICT1, /* one dictionary check byte to go */
3119 DICT0, /* waiting for inflateSetDictionary */
3120 BLOCKS, /* decompressing blocks */
3121 CHECK4, /* four check bytes to go */
3122 CHECK3, /* three check bytes to go */
3123 CHECK2, /* two check bytes to go */
3124 CHECK1, /* one check byte to go */
3125 DONE, /* finished check, done */
3126 BAD} /* got an error--stay here */
3127 mode; /* current inflate mode */
3129 /* mode dependent information */
3131 uInt method; /* if FLAGS, method byte */
3133 uLong was; /* computed check value */
3134 uLong need; /* stream check value */
3135 } check; /* if CHECK, check values to compare */
3136 uInt marker; /* if BAD, inflateSync's marker bytes count */
3137 } sub; /* submode */
3139 /* mode independent information */
3140 int nowrap; /* flag for no wrapper */
3141 uInt wbits; /* log2(window size) (8..15, defaults to 15) */
3142 inflate_blocks_statef
3143 *blocks; /* current inflate_blocks state */
3153 if (z == Z_NULL || z->state == Z_NULL)
3154 return Z_STREAM_ERROR;
3155 z->total_in = z->total_out = 0;
3157 z->state->mode = z->state->nowrap ? BLOCKS : METHOD;
3158 inflate_blocks_reset(z->state->blocks, z, &c);
3159 Trace((stderr, "inflate: reset\n"));
3169 if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL)
3170 return Z_STREAM_ERROR;
3171 if (z->state->blocks != Z_NULL)
3172 inflate_blocks_free(z->state->blocks, z, &c);
3175 Trace((stderr, "inflate: end\n"));
3180 int inflateInit2_(z, w, version, stream_size)
3183 const char *version;
3186 if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
3187 stream_size != sizeof(z_stream))
3188 return Z_VERSION_ERROR;
3190 /* initialize state */
3192 return Z_STREAM_ERROR;
3195 if (z->zalloc == Z_NULL)
3197 z->zalloc = zcalloc;
3198 z->opaque = (voidpf)0;
3200 if (z->zfree == Z_NULL) z->zfree = zcfree;
3202 if ((z->state = (struct internal_state FAR *)
3203 ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL)
3205 z->state->blocks = Z_NULL;
3207 /* handle undocumented nowrap option (no zlib header or check) */
3208 z->state->nowrap = 0;
3212 z->state->nowrap = 1;
3215 /* set window size */
3216 if (w < 8 || w > 15)
3219 return Z_STREAM_ERROR;
3221 z->state->wbits = (uInt)w;
3223 /* create inflate_blocks state */
3224 if ((z->state->blocks =
3225 inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, (uInt)1 << w))
3231 Trace((stderr, "inflate: allocated\n"));
3239 int inflateInit_(z, version, stream_size)
3241 const char *version;
3244 return inflateInit2_(z, DEF_WBITS, version, stream_size);
3248 #define NEEDBYTE {if(z->avail_in==0)goto empty;r=Z_OK;}
3249 #define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
3258 if (z == Z_NULL || z->state == Z_NULL || z->next_in == Z_NULL || f < 0)
3259 return Z_STREAM_ERROR;
3261 while (1) switch (z->state->mode)
3265 if (((z->state->sub.method = NEXTBYTE) & 0xf) != Z_DEFLATED)
3267 z->state->mode = BAD;
3268 z->msg = (char*)"unknown compression method";
3269 z->state->sub.marker = 5; /* can't try inflateSync */
3272 if ((z->state->sub.method >> 4) + 8 > z->state->wbits)
3274 z->state->mode = BAD;
3275 z->msg = (char*)"invalid window size";
3276 z->state->sub.marker = 5; /* can't try inflateSync */
3279 z->state->mode = FLAG;
3283 if (((z->state->sub.method << 8) + b) % 31)
3285 z->state->mode = BAD;
3286 z->msg = (char*)"incorrect header check";
3287 z->state->sub.marker = 5; /* can't try inflateSync */
3290 Trace((stderr, "inflate: zlib header ok\n"));
3291 if (!(b & PRESET_DICT))
3293 z->state->mode = BLOCKS;
3296 z->state->mode = DICT4;
3299 z->state->sub.check.need = (uLong)NEXTBYTE << 24;
3300 z->state->mode = DICT3;
3303 z->state->sub.check.need += (uLong)NEXTBYTE << 16;
3304 z->state->mode = DICT2;
3307 z->state->sub.check.need += (uLong)NEXTBYTE << 8;
3308 z->state->mode = DICT1;
3311 z->state->sub.check.need += (uLong)NEXTBYTE;
3312 z->adler = z->state->sub.check.need;
3313 z->state->mode = DICT0;
3316 z->state->mode = BAD;
3317 z->msg = (char*)"need dictionary";
3318 z->state->sub.marker = 0; /* can try inflateSync */
3319 return Z_STREAM_ERROR;
3321 r = inflate_blocks(z->state->blocks, z, r);
3322 if (f == Z_PACKET_FLUSH && z->avail_in == 0 && z->avail_out != 0)
3323 r = inflate_packet_flush(z->state->blocks);
3324 if (r == Z_DATA_ERROR)
3326 z->state->mode = BAD;
3327 z->state->sub.marker = 0; /* can try inflateSync */
3330 if (r != Z_STREAM_END)
3333 inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was);
3334 if (z->state->nowrap)
3336 z->state->mode = DONE;
3339 z->state->mode = CHECK4;
3342 z->state->sub.check.need = (uLong)NEXTBYTE << 24;
3343 z->state->mode = CHECK3;
3346 z->state->sub.check.need += (uLong)NEXTBYTE << 16;
3347 z->state->mode = CHECK2;
3350 z->state->sub.check.need += (uLong)NEXTBYTE << 8;
3351 z->state->mode = CHECK1;
3354 z->state->sub.check.need += (uLong)NEXTBYTE;
3356 if (z->state->sub.check.was != z->state->sub.check.need)
3358 z->state->mode = BAD;
3359 z->msg = (char*)"incorrect data check";
3360 z->state->sub.marker = 5; /* can't try inflateSync */
3363 Trace((stderr, "inflate: zlib check ok\n"));
3364 z->state->mode = DONE;
3366 return Z_STREAM_END;
3368 return Z_DATA_ERROR;
3370 return Z_STREAM_ERROR;
3374 if (f != Z_PACKET_FLUSH)
3376 z->state->mode = BAD;
3377 z->msg = (char *)"need more for packet flush";
3378 z->state->sub.marker = 0; /* can try inflateSync */
3379 return Z_DATA_ERROR;
3383 int inflateSetDictionary(z, dictionary, dictLength)
3385 const Bytef *dictionary;
3388 uInt length = dictLength;
3390 if (z == Z_NULL || z->state == Z_NULL || z->state->mode != DICT0)
3391 return Z_STREAM_ERROR;
3393 if (adler32(1L, dictionary, dictLength) != z->adler) return Z_DATA_ERROR;
3396 if (length >= ((uInt)1<<z->state->wbits))
3398 length = (1<<z->state->wbits)-1;
3399 dictionary += dictLength - length;
3401 inflate_set_dictionary(z->state->blocks, dictionary, length);
3402 z->state->mode = BLOCKS;
3407 * This subroutine adds the data at next_in/avail_in to the output history
3408 * without performing any output. The output buffer must be "caught up";
3409 * i.e. no pending output (hence s->read equals s->write), and the state must
3410 * be BLOCKS (i.e. we should be willing to see the start of a series of
3411 * BLOCKS). On exit, the output will also be caught up, and the checksum
3412 * will have been updated if need be.
3415 int inflateIncomp(z)
3418 if (z->state->mode != BLOCKS)
3419 return Z_DATA_ERROR;
3420 return inflate_addhistory(z->state->blocks, z);
3427 uInt n; /* number of bytes to look at */
3428 Bytef *p; /* pointer to bytes */
3429 uInt m; /* number of marker bytes found in a row */
3430 uLong r, w; /* temporaries to save total_in and total_out */
3433 if (z == Z_NULL || z->state == Z_NULL)
3434 return Z_STREAM_ERROR;
3435 if (z->state->mode != BAD)
3437 z->state->mode = BAD;
3438 z->state->sub.marker = 0;
3440 if ((n = z->avail_in) == 0)
3443 m = z->state->sub.marker;
3448 if (*p == (Byte)(m < 2 ? 0 : 0xff))
3458 z->total_in += p - z->next_in;
3461 z->state->sub.marker = m;
3463 /* return no joy or set up to restart on a new block */
3465 return Z_DATA_ERROR;
3466 r = z->total_in; w = z->total_out;
3468 z->total_in = r; z->total_out = w;
3469 z->state->mode = BLOCKS;
3477 /* +++ infblock.c */
3478 /* infblock.c -- interpret and process block types to last block
3479 * Copyright (C) 1995-1996 Mark Adler
3480 * For conditions of distribution and use, see copyright notice in zlib.h
3483 /* #include "zutil.h" */
3484 /* #include "infblock.h" */
3486 /* +++ inftrees.h */
3487 /* inftrees.h -- header to use inftrees.c
3488 * Copyright (C) 1995-1996 Mark Adler
3489 * For conditions of distribution and use, see copyright notice in zlib.h
3492 /* WARNING: this file should *not* be used by applications. It is
3493 part of the implementation of the compression library and is
3494 subject to change. Applications should only use zlib.h.
3497 /* Huffman code lookup table entry--this entry is four bytes for machines
3498 that have 16-bit pointers (e.g. PC's in the small or medium model). */
3500 typedef struct inflate_huft_s FAR inflate_huft;
3502 struct inflate_huft_s {
3505 Byte Exop; /* number of extra bits or operation */
3506 Byte Bits; /* number of bits in this code or subcode */
3508 Bytef *pad; /* pad structure to a power of 2 (4 bytes for */
3509 } word; /* 16-bit, 8 bytes for 32-bit machines) */
3511 uInt Base; /* literal, length base, or distance base */
3512 inflate_huft *Next; /* pointer to next level of table */
3517 extern uInt inflate_hufts;
3520 extern int inflate_trees_bits OF((
3521 uIntf *, /* 19 code lengths */
3522 uIntf *, /* bits tree desired/actual depth */
3523 inflate_huft * FAR *, /* bits tree result */
3524 z_streamp )); /* for zalloc, zfree functions */
3526 extern int inflate_trees_dynamic OF((
3527 uInt, /* number of literal/length codes */
3528 uInt, /* number of distance codes */
3529 uIntf *, /* that many (total) code lengths */
3530 uIntf *, /* literal desired/actual bit depth */
3531 uIntf *, /* distance desired/actual bit depth */
3532 inflate_huft * FAR *, /* literal/length tree result */
3533 inflate_huft * FAR *, /* distance tree result */
3534 z_streamp )); /* for zalloc, zfree functions */
3536 extern int inflate_trees_fixed OF((
3537 uIntf *, /* literal desired/actual bit depth */
3538 uIntf *, /* distance desired/actual bit depth */
3539 inflate_huft * FAR *, /* literal/length tree result */
3540 inflate_huft * FAR *)); /* distance tree result */
3542 extern int inflate_trees_free OF((
3543 inflate_huft *, /* tables to free */
3544 z_streamp )); /* for zfree function */
3546 /* --- inftrees.h */
3548 /* +++ infcodes.h */
3549 /* infcodes.h -- header to use infcodes.c
3550 * Copyright (C) 1995-1996 Mark Adler
3551 * For conditions of distribution and use, see copyright notice in zlib.h
3554 /* WARNING: this file should *not* be used by applications. It is
3555 part of the implementation of the compression library and is
3556 subject to change. Applications should only use zlib.h.
3559 struct inflate_codes_state;
3560 typedef struct inflate_codes_state FAR inflate_codes_statef;
3562 extern inflate_codes_statef *inflate_codes_new OF((
3564 inflate_huft *, inflate_huft *,
3567 extern int inflate_codes OF((
3568 inflate_blocks_statef *,
3572 extern void inflate_codes_free OF((
3573 inflate_codes_statef *,
3576 /* --- infcodes.h */
3579 /* infutil.h -- types and macros common to blocks and codes
3580 * Copyright (C) 1995-1996 Mark Adler
3581 * For conditions of distribution and use, see copyright notice in zlib.h
3584 /* WARNING: this file should *not* be used by applications. It is
3585 part of the implementation of the compression library and is
3586 subject to change. Applications should only use zlib.h.
3593 TYPE, /* get type bits (3, including end bit) */
3594 LENS, /* get lengths for stored */
3595 STORED, /* processing stored block */
3596 TABLE, /* get table lengths */
3597 BTREE, /* get bit lengths tree for a dynamic block */
3598 DTREE, /* get length, distance trees for a dynamic block */
3599 CODES, /* processing fixed or dynamic block */
3600 DRY, /* output remaining window bytes */
3601 DONEB, /* finished last block, done */
3602 BADB} /* got a data error--stuck here */
3605 /* inflate blocks semi-private state */
3606 struct inflate_blocks_state {
3609 inflate_block_mode mode; /* current inflate_block mode */
3611 /* mode dependent information */
3613 uInt left; /* if STORED, bytes left to copy */
3615 uInt table; /* table lengths (14 bits) */
3616 uInt index; /* index into blens (or border) */
3617 uIntf *blens; /* bit lengths of codes */
3618 uInt bb; /* bit length tree depth */
3619 inflate_huft *tb; /* bit length decoding tree */
3620 } trees; /* if DTREE, decoding info for trees */
3623 inflate_huft *td; /* trees to free */
3624 inflate_codes_statef
3626 } decode; /* if CODES, current state */
3627 } sub; /* submode */
3628 uInt last; /* true if this block is the last block */
3630 /* mode independent information */
3631 uInt bitk; /* bits in bit buffer */
3632 uLong bitb; /* bit buffer */
3633 Bytef *window; /* sliding window */
3634 Bytef *end; /* one byte after sliding window */
3635 Bytef *read; /* window read pointer */
3636 Bytef *write; /* window write pointer */
3637 check_func checkfn; /* check function */
3638 uLong check; /* check on output */
3643 /* defines for inflate input/output */
3644 /* update pointers and return */
3645 #define UPDBITS {s->bitb=b;s->bitk=k;}
3646 #define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
3647 #define UPDOUT {s->write=q;}
3648 #define UPDATE {UPDBITS UPDIN UPDOUT}
3649 #define LEAVE {UPDATE return inflate_flush(s,z,r);}
3650 /* get bytes and bits */
3651 #define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
3652 #define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
3653 #define NEXTBYTE (n--,*p++)
3654 #define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
3655 #define DUMPBITS(j) {b>>=(j);k-=(j);}
3657 #define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q)
3658 #define LOADOUT {q=s->write;m=(uInt)WAVAIL;}
3659 #define WWRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}}
3660 #define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
3661 #define NEEDOUT {if(m==0){WWRAP if(m==0){FLUSH WWRAP if(m==0) LEAVE}}r=Z_OK;}
3662 #define OUTBYTE(a) {*q++=(Byte)(a);m--;}
3663 /* load local pointers */
3664 #define LOAD {LOADIN LOADOUT}
3666 /* masks for lower bits (size given to avoid silly warnings with Visual C++) */
3667 extern uInt inflate_mask[17];
3669 /* copy as much as possible from the sliding window to the output area */
3670 extern int inflate_flush OF((
3671 inflate_blocks_statef *,
3675 #ifndef NO_DUMMY_DECL
3676 struct internal_state {int dummy;}; /* for buggy compilers */
3682 #ifndef NO_DUMMY_DECL
3683 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
3686 /* Table for deflate from PKZIP's appnote.txt. */
3687 local const uInt border[] = { /* Order of the bit length code lengths */
3688 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
3691 Notes beyond the 1.93a appnote.txt:
3693 1. Distance pointers never point before the beginning of the output
3695 2. Distance pointers can point back across blocks, up to 32k away.
3696 3. There is an implied maximum of 7 bits for the bit length table and
3697 15 bits for the actual data.
3698 4. If only one code exists, then it is encoded using one bit. (Zero
3699 would be more efficient, but perhaps a little confusing.) If two
3700 codes exist, they are coded using one bit each (0 and 1).
3701 5. There is no way of sending zero distance codes--a dummy must be
3702 sent if there are none. (History: a pre 2.0 version of PKZIP would
3703 store blocks with no distance codes, but this was discovered to be
3704 too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
3705 zero distance codes, which is sent as one code of zero bits in
3707 6. There are up to 286 literal/length codes. Code 256 represents the
3708 end-of-block. Note however that the static length tree defines
3709 288 codes just to fill out the Huffman codes. Codes 286 and 287
3710 cannot be used though, since there is no length base or extra bits
3711 defined for them. Similarily, there are up to 30 distance codes.
3712 However, static trees define 32 codes (all 5 bits) to fill out the
3713 Huffman codes, but the last two had better not show up in the data.
3714 7. Unzip can check dynamic Huffman blocks for complete code sets.
3715 The exception is that a single code would not be complete (see #4).
3716 8. The five bits following the block type is really the number of
3717 literal codes sent minus 257.
3718 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
3719 (1+6+6). Therefore, to output three times the length, you output
3720 three codes (1+1+1), whereas to output four times the same length,
3721 you only need two codes (1+3). Hmm.
3722 10. In the tree reconstruction algorithm, Code = Code + Increment
3723 only if BitLength(i) is not zero. (Pretty obvious.)
3724 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
3725 12. Note: length code 284 can represent 227-258, but length code 285
3726 really is 258. The last length deserves its own, short code
3727 since it gets used a lot in very redundant files. The length
3728 258 is special since 258 - 3 (the min match length) is 255.
3729 13. The literal/length and distance code bit lengths are read as a
3730 single stream of lengths. It is possible (and advantageous) for
3731 a repeat code (16, 17, or 18) to go across the boundary between
3732 the two sets of lengths.
3736 void inflate_blocks_reset(s, z, c)
3737 inflate_blocks_statef *s;
3741 if (s->checkfn != Z_NULL)
3743 if (s->mode == BTREE || s->mode == DTREE)
3744 ZFREE(z, s->sub.trees.blens);
3745 if (s->mode == CODES)
3747 inflate_codes_free(s->sub.decode.codes, z);
3748 inflate_trees_free(s->sub.decode.td, z);
3749 inflate_trees_free(s->sub.decode.tl, z);
3754 s->read = s->write = s->window;
3755 if (s->checkfn != Z_NULL)
3756 z->adler = s->check = (*s->checkfn)(0L, Z_NULL, 0);
3757 Trace((stderr, "inflate: blocks reset\n"));
3761 inflate_blocks_statef *inflate_blocks_new(z, c, w)
3766 inflate_blocks_statef *s;
3768 if ((s = (inflate_blocks_statef *)ZALLOC
3769 (z,1,sizeof(struct inflate_blocks_state))) == Z_NULL)
3771 if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL)
3776 s->end = s->window + w;
3779 Trace((stderr, "inflate: blocks allocated\n"));
3780 inflate_blocks_reset(s, z, &s->check);
3786 extern uInt inflate_hufts;
3788 int inflate_blocks(s, z, r)
3789 inflate_blocks_statef *s;
3793 uInt t; /* temporary storage */
3794 uLong b; /* bit buffer */
3795 uInt k; /* bits in bit buffer */
3796 Bytef *p; /* input data pointer */
3797 uInt n; /* bytes available there */
3798 Bytef *q; /* output window write pointer */
3799 uInt m; /* bytes to end of window or read pointer */
3801 /* copy input/output information to locals (UPDATE macro restores) */
3804 /* process input based on current state */
3805 while (1) switch (s->mode)
3813 case 0: /* stored */
3814 Trace((stderr, "inflate: stored block%s\n",
3815 s->last ? " (last)" : ""));
3817 t = k & 7; /* go to byte boundary */
3819 s->mode = LENS; /* get length of stored block */
3822 Trace((stderr, "inflate: fixed codes block%s\n",
3823 s->last ? " (last)" : ""));
3826 inflate_huft *tl, *td;
3828 inflate_trees_fixed(&bl, &bd, &tl, &td);
3829 s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z);
3830 if (s->sub.decode.codes == Z_NULL)
3835 s->sub.decode.tl = Z_NULL; /* don't try to free these */
3836 s->sub.decode.td = Z_NULL;
3841 case 2: /* dynamic */
3842 Trace((stderr, "inflate: dynamic codes block%s\n",
3843 s->last ? " (last)" : ""));
3847 case 3: /* illegal */
3850 z->msg = (char*)"invalid block type";
3857 if ((((~b) >> 16) & 0xffff) != (b & 0xffff))
3860 z->msg = (char*)"invalid stored block lengths";
3864 s->sub.left = (uInt)b & 0xffff;
3865 b = k = 0; /* dump bits */
3866 Tracev((stderr, "inflate: stored length %u\n", s->sub.left));
3867 s->mode = s->sub.left ? STORED : (s->last ? DRY : TYPE);
3879 if ((s->sub.left -= t) != 0)
3881 Tracev((stderr, "inflate: stored end, %lu total out\n",
3882 z->total_out + (q >= s->read ? q - s->read :
3883 (s->end - s->read) + (q - s->window))));
3884 s->mode = s->last ? DRY : TYPE;
3888 s->sub.trees.table = t = (uInt)b & 0x3fff;
3889 #ifndef PKZIP_BUG_WORKAROUND
3890 if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
3893 z->msg = (char*)"too many length or distance symbols";
3898 t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
3901 if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
3907 s->sub.trees.index = 0;
3908 Tracev((stderr, "inflate: table sizes ok\n"));
3911 while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10))
3914 s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7;
3917 while (s->sub.trees.index < 19)
3918 s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
3919 s->sub.trees.bb = 7;
3920 t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
3921 &s->sub.trees.tb, z);
3925 if (r == Z_DATA_ERROR) {
3926 ZFREE(z, s->sub.trees.blens);
3931 s->sub.trees.index = 0;
3932 Tracev((stderr, "inflate: bits tree ok\n"));
3935 while (t = s->sub.trees.table,
3936 s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
3941 t = s->sub.trees.bb;
3943 h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]);
3944 t = h->word.what.Bits;
3949 s->sub.trees.blens[s->sub.trees.index++] = c;
3951 else /* c == 16..18 */
3953 i = c == 18 ? 7 : c - 14;
3954 j = c == 18 ? 11 : 3;
3957 j += (uInt)b & inflate_mask[i];
3959 i = s->sub.trees.index;
3960 t = s->sub.trees.table;
3961 if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) ||
3964 inflate_trees_free(s->sub.trees.tb, z);
3965 ZFREE(z, s->sub.trees.blens);
3967 z->msg = (char*)"invalid bit length repeat";
3971 c = c == 16 ? s->sub.trees.blens[i - 1] : 0;
3973 s->sub.trees.blens[i++] = c;
3975 s->sub.trees.index = i;
3978 inflate_trees_free(s->sub.trees.tb, z);
3979 s->sub.trees.tb = Z_NULL;
3982 inflate_huft *tl, *td;
3983 inflate_codes_statef *c;
3985 bl = 9; /* must be <= 9 for lookahead assumptions */
3986 bd = 6; /* must be <= 9 for lookahead assumptions */
3987 t = s->sub.trees.table;
3991 t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
3992 s->sub.trees.blens, &bl, &bd, &tl, &td, z);
3995 if (t == (uInt)Z_DATA_ERROR) {
3996 ZFREE(z, s->sub.trees.blens);
4002 Tracev((stderr, "inflate: trees ok, %d * %d bytes used\n",
4003 inflate_hufts, sizeof(inflate_huft)));
4004 if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
4006 inflate_trees_free(td, z);
4007 inflate_trees_free(tl, z);
4012 * this ZFREE must occur *BEFORE* we mess with sub.decode, because
4013 * sub.trees is union'd with sub.decode.
4015 ZFREE(z, s->sub.trees.blens);
4016 s->sub.decode.codes = c;
4017 s->sub.decode.tl = tl;
4018 s->sub.decode.td = td;
4023 if ((r = inflate_codes(s, z, r)) != Z_STREAM_END)
4024 return inflate_flush(s, z, r);
4026 inflate_codes_free(s->sub.decode.codes, z);
4027 inflate_trees_free(s->sub.decode.td, z);
4028 inflate_trees_free(s->sub.decode.tl, z);
4030 Tracev((stderr, "inflate: codes end, %lu total out\n",
4031 z->total_out + (q >= s->read ? q - s->read :
4032 (s->end - s->read) + (q - s->window))));
4038 if (k > 7) /* return unused byte, if any */
4040 Assert(k < 16, "inflate_codes grabbed too many bytes")
4043 p--; /* can always return one */
4048 if (s->read != s->write)
4064 int inflate_blocks_free(s, z, c)
4065 inflate_blocks_statef *s;
4069 inflate_blocks_reset(s, z, c);
4070 ZFREE(z, s->window);
4072 Trace((stderr, "inflate: blocks freed\n"));
4077 void inflate_set_dictionary(s, d, n)
4078 inflate_blocks_statef *s;
4082 zmemcpy((charf *)s->window, d, n);
4083 s->read = s->write = s->window + n;
4087 * This subroutine adds the data at next_in/avail_in to the output history
4088 * without performing any output. The output buffer must be "caught up";
4089 * i.e. no pending output (hence s->read equals s->write), and the state must
4090 * be BLOCKS (i.e. we should be willing to see the start of a series of
4091 * BLOCKS). On exit, the output will also be caught up, and the checksum
4092 * will have been updated if need be.
4094 int inflate_addhistory(s, z)
4095 inflate_blocks_statef *s;
4098 uLong b; /* bit buffer */ /* NOT USED HERE */
4099 uInt k; /* bits in bit buffer */ /* NOT USED HERE */
4100 uInt t; /* temporary storage */
4101 Bytef *p; /* input data pointer */
4102 uInt n; /* bytes available there */
4103 Bytef *q; /* output window write pointer */
4104 uInt m; /* bytes to end of window or read pointer */
4106 if (s->read != s->write)
4107 return Z_STREAM_ERROR;
4108 if (s->mode != TYPE)
4109 return Z_DATA_ERROR;
4111 /* we're ready to rock */
4113 /* while there is input ready, copy to output buffer, moving
4114 * pointers as needed.
4117 t = n; /* how many to do */
4118 /* is there room until end of buffer? */
4120 /* update check information */
4121 if (s->checkfn != Z_NULL)
4122 s->check = (*s->checkfn)(s->check, q, t);
4128 s->read = q; /* drag read pointer forward */
4129 /* WWRAP */ /* expand WWRAP macro by hand to handle s->read */
4131 s->read = q = s->window;
4141 * At the end of a Deflate-compressed PPP packet, we expect to have seen
4142 * a `stored' block type value but not the (zero) length bytes.
4144 int inflate_packet_flush(s)
4145 inflate_blocks_statef *s;
4147 if (s->mode != LENS)
4148 return Z_DATA_ERROR;
4152 /* --- infblock.c */
4154 /* +++ inftrees.c */
4155 /* inftrees.c -- generate Huffman trees for efficient decoding
4156 * Copyright (C) 1995-1996 Mark Adler
4157 * For conditions of distribution and use, see copyright notice in zlib.h
4160 /* #include "zutil.h" */
4161 /* #include "inftrees.h" */
4163 char inflate_copyright[] = " inflate 1.0.4 Copyright 1995-1996 Mark Adler ";
4165 If you use the zlib library in a product, an acknowledgment is welcome
4166 in the documentation of your product. If for some reason you cannot
4167 include such an acknowledgment, I would appreciate that you keep this
4168 copyright string in the executable of your product.
4171 #ifndef NO_DUMMY_DECL
4172 struct internal_state {int dummy;}; /* for buggy compilers */
4175 /* simplify the use of the inflate_huft type with some defines */
4176 #define base more.Base
4177 #define next more.Next
4178 #define exop word.what.Exop
4179 #define bits word.what.Bits
4182 local int huft_build OF((
4183 uIntf *, /* code lengths in bits */
4184 uInt, /* number of codes */
4185 uInt, /* number of "simple" codes */
4186 const uIntf *, /* list of base values for non-simple codes */
4187 const uIntf *, /* list of extra bits for non-simple codes */
4188 inflate_huft * FAR*,/* result: starting table */
4189 uIntf *, /* maximum lookup bits (returns actual) */
4190 z_streamp )); /* for zalloc function */
4192 local voidpf falloc OF((
4193 voidpf, /* opaque pointer (not used) */
4194 uInt, /* number of items */
4195 uInt)); /* size of item */
4197 /* Tables for deflate from PKZIP's appnote.txt. */
4198 local const uInt cplens[31] = { /* Copy lengths for literal codes 257..285 */
4199 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
4200 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
4201 /* see note #13 above about 258 */
4202 local const uInt cplext[31] = { /* Extra bits for literal codes 257..285 */
4203 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
4204 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 112, 112}; /* 112==invalid */
4205 local const uInt cpdist[30] = { /* Copy offsets for distance codes 0..29 */
4206 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
4207 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
4208 8193, 12289, 16385, 24577};
4209 local const uInt cpdext[30] = { /* Extra bits for distance codes */
4210 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
4211 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
4215 Huffman code decoding is performed using a multi-level table lookup.
4216 The fastest way to decode is to simply build a lookup table whose
4217 size is determined by the longest code. However, the time it takes
4218 to build this table can also be a factor if the data being decoded
4219 is not very long. The most common codes are necessarily the
4220 shortest codes, so those codes dominate the decoding time, and hence
4221 the speed. The idea is you can have a shorter table that decodes the
4222 shorter, more probable codes, and then point to subsidiary tables for
4223 the longer codes. The time it costs to decode the longer codes is
4224 then traded against the time it takes to make longer tables.
4226 This results of this trade are in the variables lbits and dbits
4227 below. lbits is the number of bits the first level table for literal/
4228 length codes can decode in one step, and dbits is the same thing for
4229 the distance codes. Subsequent tables are also less than or equal to
4230 those sizes. These values may be adjusted either when all of the
4231 codes are shorter than that, in which case the longest code length in
4232 bits is used, or when the shortest code is *longer* than the requested
4233 table size, in which case the length of the shortest code in bits is
4236 There are two different values for the two tables, since they code a
4237 different number of possibilities each. The literal/length table
4238 codes 286 possible values, or in a flat code, a little over eight
4239 bits. The distance table codes 30 possible values, or a little less
4240 than five bits, flat. The optimum values for speed end up being
4241 about one bit more than those, so lbits is 8+1 and dbits is 5+1.
4242 The optimum values may differ though from machine to machine, and
4243 possibly even between compilers. Your mileage may vary.
4247 /* If BMAX needs to be larger than 16, then h and x[] should be uLong. */
4248 #define BMAX 15 /* maximum bit length of any code */
4249 #define N_MAX 288 /* maximum number of codes in any set */
4255 local int huft_build(b, n, s, d, e, t, m, zs)
4256 uIntf *b; /* code lengths in bits (all assumed <= BMAX) */
4257 uInt n; /* number of codes (assumed <= N_MAX) */
4258 uInt s; /* number of simple-valued codes (0..s-1) */
4259 const uIntf *d; /* list of base values for non-simple codes */
4260 const uIntf *e; /* list of extra bits for non-simple codes */
4261 inflate_huft * FAR *t; /* result: starting table */
4262 uIntf *m; /* maximum lookup bits, returns actual */
4263 z_streamp zs; /* for zalloc function */
4264 /* Given a list of code lengths and a maximum table size, make a set of
4265 tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR
4266 if the given code set is incomplete (the tables are still built in this
4267 case), Z_DATA_ERROR if the input is invalid (an over-subscribed set of
4268 lengths), or Z_MEM_ERROR if not enough memory. */
4271 uInt a; /* counter for codes of length k */
4272 uInt c[BMAX+1]; /* bit length count table */
4273 uInt f; /* i repeats in table every f entries */
4274 int g; /* maximum code length */
4275 int h; /* table level */
4276 register uInt i; /* counter, current code */
4277 register uInt j; /* counter */
4278 register int k; /* number of bits in current code */
4279 int l; /* bits per table (returned in m) */
4280 register uIntf *p; /* pointer into c[], b[], or v[] */
4281 inflate_huft *q; /* points to current table */
4282 struct inflate_huft_s r; /* table entry for structure assignment */
4283 inflate_huft *u[BMAX]; /* table stack */
4284 uInt v[N_MAX]; /* values in order of bit length */
4285 register int w; /* bits before this table == (l * h) */
4286 uInt x[BMAX+1]; /* bit offsets, then code stack */
4287 uIntf *xp; /* pointer into x */
4288 int y; /* number of dummy codes added */
4289 uInt z; /* number of entries in current table */
4292 /* Generate counts for each bit length */
4294 #define C0 *p++ = 0;
4295 #define C2 C0 C0 C0 C0
4296 #define C4 C2 C2 C2 C2
4297 C4 /* clear c[]--assume BMAX+1 is 16 */
4300 c[*p++]++; /* assume all entries <= BMAX */
4302 if (c[0] == n) /* null input--all zero length codes */
4304 *t = (inflate_huft *)Z_NULL;
4310 /* Find minimum and maximum length, bound *m by those */
4312 for (j = 1; j <= BMAX; j++)
4315 k = j; /* minimum code length */
4318 for (i = BMAX; i; i--)
4321 g = i; /* maximum code length */
4327 /* Adjust last length count to fill out codes, if needed */
4328 for (y = 1 << j; j < i; j++, y <<= 1)
4329 if ((y -= c[j]) < 0)
4330 return Z_DATA_ERROR;
4331 if ((y -= c[i]) < 0)
4332 return Z_DATA_ERROR;
4336 /* Generate starting offsets into the value table for each length */
4338 p = c + 1; xp = x + 2;
4339 while (--i) { /* note that i == g from above */
4340 *xp++ = (j += *p++);
4344 /* Make a table of values in order of bit lengths */
4347 if ((j = *p++) != 0)
4350 n = x[g]; /* set n to length of v */
4353 /* Generate the Huffman codes and for each, make the table entries */
4354 x[0] = i = 0; /* first Huffman code is zero */
4355 p = v; /* grab values in bit order */
4356 h = -1; /* no tables yet--level -1 */
4357 w = -l; /* bits decoded == (l * h) */
4358 u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */
4359 q = (inflate_huft *)Z_NULL; /* ditto */
4362 /* go through the bit lengths (k already is bits in shortest code) */
4368 /* here i is the Huffman code of length k bits for value *p */
4369 /* make tables up to required level */
4373 w += l; /* previous table always l bits */
4375 /* compute minimum size table less than or equal to l bits */
4377 z = z > (uInt)l ? l : z; /* table size upper limit */
4378 if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
4379 { /* too few codes for k-w bit table */
4380 f -= a + 1; /* deduct codes from patterns left */
4383 while (++j < z) /* try smaller tables up to z bits */
4385 if ((f <<= 1) <= *++xp)
4386 break; /* enough codes to use up j bits */
4387 f -= *xp; /* else deduct codes from patterns */
4390 z = 1 << j; /* table entries for j-bit table */
4392 /* allocate and link in new table */
4393 if ((q = (inflate_huft *)ZALLOC
4394 (zs,z + 1,sizeof(inflate_huft))) == Z_NULL)
4397 inflate_trees_free(u[0], zs);
4398 return Z_MEM_ERROR; /* not enough memory */
4401 inflate_hufts += z + 1;
4403 *t = q + 1; /* link to list for huft_free() */
4404 *(t = &(q->next)) = Z_NULL;
4405 u[h] = ++q; /* table starts after link */
4407 /* connect to last table, if there is one */
4410 x[h] = i; /* save pattern for backing up */
4411 r.bits = (Byte)l; /* bits to dump before this table */
4412 r.exop = (Byte)j; /* bits in this table */
4413 r.next = q; /* pointer to this table */
4414 j = i >> (w - l); /* (get around Turbo C bug) */
4415 u[h-1][j] = r; /* connect to last table */
4419 /* set up table entry in r */
4420 r.bits = (Byte)(k - w);
4422 r.exop = 128 + 64; /* out of values--invalid code */
4425 r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */
4426 r.base = *p++; /* simple code is just the value */
4430 r.exop = (Byte)(e[*p - s] + 16 + 64);/* non-simple--look up in lists */
4431 r.base = d[*p++ - s];
4434 /* fill code-like entries with r */
4436 for (j = i >> w; j < z; j += f)
4439 /* backwards increment the k-bit code i */
4440 for (j = 1 << (k - 1); i & j; j >>= 1)
4444 /* backup over finished tables */
4445 while ((i & ((1 << w) - 1)) != x[h])
4447 h--; /* don't need to update q */
4454 /* Return Z_BUF_ERROR if we were given an incomplete table */
4455 return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK;
4459 int inflate_trees_bits(c, bb, tb, z)
4460 uIntf *c; /* 19 code lengths */
4461 uIntf *bb; /* bits tree desired/actual depth */
4462 inflate_huft * FAR *tb; /* bits tree result */
4463 z_streamp z; /* for zfree function */
4467 r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL, tb, bb, z);
4468 if (r == Z_DATA_ERROR)
4469 z->msg = (char*)"oversubscribed dynamic bit lengths tree";
4470 else if (r == Z_BUF_ERROR || *bb == 0)
4472 inflate_trees_free(*tb, z);
4473 z->msg = (char*)"incomplete dynamic bit lengths tree";
4480 int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, z)
4481 uInt nl; /* number of literal/length codes */
4482 uInt nd; /* number of distance codes */
4483 uIntf *c; /* that many (total) code lengths */
4484 uIntf *bl; /* literal desired/actual bit depth */
4485 uIntf *bd; /* distance desired/actual bit depth */
4486 inflate_huft * FAR *tl; /* literal/length tree result */
4487 inflate_huft * FAR *td; /* distance tree result */
4488 z_streamp z; /* for zfree function */
4492 /* build literal/length tree */
4493 r = huft_build(c, nl, 257, cplens, cplext, tl, bl, z);
4494 if (r != Z_OK || *bl == 0)
4496 if (r == Z_DATA_ERROR)
4497 z->msg = (char*)"oversubscribed literal/length tree";
4498 else if (r != Z_MEM_ERROR)
4500 inflate_trees_free(*tl, z);
4501 z->msg = (char*)"incomplete literal/length tree";
4507 /* build distance tree */
4508 r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, z);
4509 if (r != Z_OK || (*bd == 0 && nl > 257))
4511 if (r == Z_DATA_ERROR)
4512 z->msg = (char*)"oversubscribed distance tree";
4513 else if (r == Z_BUF_ERROR) {
4514 #ifdef PKZIP_BUG_WORKAROUND
4518 inflate_trees_free(*td, z);
4519 z->msg = (char*)"incomplete distance tree";
4522 else if (r != Z_MEM_ERROR)
4524 z->msg = (char*)"empty distance tree with lengths";
4527 inflate_trees_free(*tl, z);
4537 /* build fixed tables only once--keep them here */
4538 local int fixed_built = 0;
4539 #define FIXEDH 530 /* number of hufts used by fixed tables */
4540 local inflate_huft fixed_mem[FIXEDH];
4541 local uInt fixed_bl;
4542 local uInt fixed_bd;
4543 local inflate_huft *fixed_tl;
4544 local inflate_huft *fixed_td;
4547 local voidpf falloc(q, n, s)
4548 voidpf q; /* opaque pointer */
4549 uInt n; /* number of items */
4550 uInt s; /* size of item */
4552 Assert(s == sizeof(inflate_huft) && n <= *(intf *)q,
4553 "inflate_trees falloc overflow");
4554 *(intf *)q -= n+s-s; /* s-s to avoid warning */
4555 return (voidpf)(fixed_mem + *(intf *)q);
4559 int inflate_trees_fixed(bl, bd, tl, td)
4560 uIntf *bl; /* literal desired/actual bit depth */
4561 uIntf *bd; /* distance desired/actual bit depth */
4562 inflate_huft * FAR *tl; /* literal/length tree result */
4563 inflate_huft * FAR *td; /* distance tree result */
4565 /* build fixed tables if not already (multiple overlapped executions ok) */
4568 int k; /* temporary variable */
4569 unsigned c[288]; /* length list for huft_build */
4570 z_stream z; /* for falloc function */
4571 int f = FIXEDH; /* number of hufts left in fixed_mem */
4573 /* set up fake z_stream for memory routines */
4576 z.opaque = (voidpf)&f;
4579 for (k = 0; k < 144; k++)
4581 for (; k < 256; k++)
4583 for (; k < 280; k++)
4585 for (; k < 288; k++)
4588 huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl, &z);
4590 /* distance table */
4591 for (k = 0; k < 30; k++)
4594 huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd, &z);
4597 Assert(f == 0, "invalid build of fixed tables");
4608 int inflate_trees_free(t, z)
4609 inflate_huft *t; /* table to free */
4610 z_streamp z; /* for zfree function */
4611 /* Free the malloc'ed tables built by huft_build(), which makes a linked
4612 list of the tables it made, with the links in a dummy first entry of
4615 register inflate_huft *p, *q, *r;
4617 /* Reverse linked list */
4627 /* Go through linked list, freeing from the malloced (t[-1]) address. */
4636 /* --- inftrees.c */
4638 /* +++ infcodes.c */
4639 /* infcodes.c -- process literals and length/distance pairs
4640 * Copyright (C) 1995-1996 Mark Adler
4641 * For conditions of distribution and use, see copyright notice in zlib.h
4644 /* #include "zutil.h" */
4645 /* #include "inftrees.h" */
4646 /* #include "infblock.h" */
4647 /* #include "infcodes.h" */
4648 /* #include "infutil.h" */
4651 /* inffast.h -- header to use inffast.c
4652 * Copyright (C) 1995-1996 Mark Adler
4653 * For conditions of distribution and use, see copyright notice in zlib.h
4656 /* WARNING: this file should *not* be used by applications. It is
4657 part of the implementation of the compression library and is
4658 subject to change. Applications should only use zlib.h.
4661 extern int inflate_fast OF((
4666 inflate_blocks_statef *,
4670 /* simplify the use of the inflate_huft type with some defines */
4671 #define base more.Base
4672 #define next more.Next
4673 #define exop word.what.Exop
4674 #define bits word.what.Bits
4676 /* inflate codes private state */
4677 struct inflate_codes_state {
4680 enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
4681 START, /* x: set up for LEN */
4682 LEN, /* i: get length/literal/eob next */
4683 LENEXT, /* i: getting length extra (have base) */
4684 DIST, /* i: get distance next */
4685 DISTEXT, /* i: getting distance extra */
4686 COPY, /* o: copying bytes in window, waiting for space */
4687 LIT, /* o: got literal, waiting for output space */
4688 WASH, /* o: got eob, possibly still output waiting */
4689 END, /* x: got eob and all data flushed */
4690 BADCODE} /* x: got error */
4691 mode; /* current inflate_codes mode */
4693 /* mode dependent information */
4697 inflate_huft *tree; /* pointer into tree */
4698 uInt need; /* bits needed */
4699 } code; /* if LEN or DIST, where in tree */
4700 uInt lit; /* if LIT, literal */
4702 uInt get; /* bits to get for extra */
4703 uInt dist; /* distance back to copy from */
4704 } copy; /* if EXT or COPY, where and how much */
4705 } sub; /* submode */
4707 /* mode independent information */
4708 Byte lbits; /* ltree bits decoded per branch */
4709 Byte dbits; /* dtree bits decoder per branch */
4710 inflate_huft *ltree; /* literal/length/eob tree */
4711 inflate_huft *dtree; /* distance tree */
4716 inflate_codes_statef *inflate_codes_new(bl, bd, tl, td, z)
4719 inflate_huft *td; /* need separate declaration for Borland C++ */
4722 inflate_codes_statef *c;
4724 if ((c = (inflate_codes_statef *)
4725 ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL)
4728 c->lbits = (Byte)bl;
4729 c->dbits = (Byte)bd;
4732 Tracev((stderr, "inflate: codes new\n"));
4738 int inflate_codes(s, z, r)
4739 inflate_blocks_statef *s;
4743 uInt j; /* temporary storage */
4744 inflate_huft *t; /* temporary pointer */
4745 uInt e; /* extra bits or operation */
4746 uLong b; /* bit buffer */
4747 uInt k; /* bits in bit buffer */
4748 Bytef *p; /* input data pointer */
4749 uInt n; /* bytes available there */
4750 Bytef *q; /* output window write pointer */
4751 uInt m; /* bytes to end of window or read pointer */
4752 Bytef *f; /* pointer to copy strings from */
4753 inflate_codes_statef *c = s->sub.decode.codes; /* codes state */
4755 /* copy input/output information to locals (UPDATE macro restores) */
4758 /* process input and output based on current state */
4759 while (1) switch (c->mode)
4760 { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
4761 case START: /* x: set up for LEN */
4763 if (m >= 258 && n >= 10)
4766 r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z);
4770 c->mode = r == Z_STREAM_END ? WASH : BADCODE;
4775 c->sub.code.need = c->lbits;
4776 c->sub.code.tree = c->ltree;
4778 case LEN: /* i: get length/literal/eob next */
4779 j = c->sub.code.need;
4781 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
4783 e = (uInt)(t->exop);
4784 if (e == 0) /* literal */
4786 c->sub.lit = t->base;
4787 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
4788 "inflate: literal '%c'\n" :
4789 "inflate: literal 0x%02x\n", t->base));
4793 if (e & 16) /* length */
4795 c->sub.copy.get = e & 15;
4800 if ((e & 64) == 0) /* next table */
4802 c->sub.code.need = e;
4803 c->sub.code.tree = t->next;
4806 if (e & 32) /* end of block */
4808 Tracevv((stderr, "inflate: end of block\n"));
4812 c->mode = BADCODE; /* invalid code */
4813 z->msg = (char*)"invalid literal/length code";
4816 case LENEXT: /* i: getting length extra (have base) */
4817 j = c->sub.copy.get;
4819 c->len += (uInt)b & inflate_mask[j];
4821 c->sub.code.need = c->dbits;
4822 c->sub.code.tree = c->dtree;
4823 Tracevv((stderr, "inflate: length %u\n", c->len));
4825 case DIST: /* i: get distance next */
4826 j = c->sub.code.need;
4828 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]);
4830 e = (uInt)(t->exop);
4831 if (e & 16) /* distance */
4833 c->sub.copy.get = e & 15;
4834 c->sub.copy.dist = t->base;
4838 if ((e & 64) == 0) /* next table */
4840 c->sub.code.need = e;
4841 c->sub.code.tree = t->next;
4844 c->mode = BADCODE; /* invalid code */
4845 z->msg = (char*)"invalid distance code";
4848 case DISTEXT: /* i: getting distance extra */
4849 j = c->sub.copy.get;
4851 c->sub.copy.dist += (uInt)b & inflate_mask[j];
4853 Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist));
4855 case COPY: /* o: copying bytes in window, waiting for space */
4856 #ifndef __TURBOC__ /* Turbo C bug for following expression */
4857 f = (uInt)(q - s->window) < c->sub.copy.dist ?
4858 s->end - (c->sub.copy.dist - (q - s->window)) :
4859 q - c->sub.copy.dist;
4861 f = q - c->sub.copy.dist;
4862 if ((uInt)(q - s->window) < c->sub.copy.dist)
4863 f = s->end - (c->sub.copy.dist - (uInt)(q - s->window));
4875 case LIT: /* o: got literal, waiting for output space */
4880 case WASH: /* o: got eob, possibly more output */
4882 if (s->read != s->write)
4888 case BADCODE: /* x: got error */
4898 void inflate_codes_free(c, z)
4899 inflate_codes_statef *c;
4903 Tracev((stderr, "inflate: codes free\n"));
4905 /* --- infcodes.c */
4908 /* inflate_util.c -- data and routines common to blocks and codes
4909 * Copyright (C) 1995-1996 Mark Adler
4910 * For conditions of distribution and use, see copyright notice in zlib.h
4913 /* #include "zutil.h" */
4914 /* #include "infblock.h" */
4915 /* #include "inftrees.h" */
4916 /* #include "infcodes.h" */
4917 /* #include "infutil.h" */
4919 #ifndef NO_DUMMY_DECL
4920 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
4923 /* And'ing with mask[n] masks the lower n bits */
4924 uInt inflate_mask[17] = {
4926 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
4927 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
4931 /* copy as much as possible from the sliding window to the output area */
4932 int inflate_flush(s, z, r)
4933 inflate_blocks_statef *s;
4941 /* local copies of source and destination pointers */
4945 /* compute number of bytes to copy as far as end of window */
4946 n = (uInt)((q <= s->write ? s->write : s->end) - q);
4947 if (n > z->avail_out) n = z->avail_out;
4948 if (n && r == Z_BUF_ERROR) r = Z_OK;
4950 /* update counters */
4954 /* update check information */
4955 if (s->checkfn != Z_NULL)
4956 z->adler = s->check = (*s->checkfn)(s->check, q, n);
4958 /* copy as far as end of window */
4965 /* see if more to copy at beginning of window */
4970 if (s->write == s->end)
4971 s->write = s->window;
4973 /* compute bytes to copy */
4974 n = (uInt)(s->write - q);
4975 if (n > z->avail_out) n = z->avail_out;
4976 if (n && r == Z_BUF_ERROR) r = Z_OK;
4978 /* update counters */
4982 /* update check information */
4983 if (s->checkfn != Z_NULL)
4984 z->adler = s->check = (*s->checkfn)(s->check, q, n);
4994 /* update pointers */
5004 /* inffast.c -- process literals and length/distance pairs fast
5005 * Copyright (C) 1995-1996 Mark Adler
5006 * For conditions of distribution and use, see copyright notice in zlib.h
5009 /* #include "zutil.h" */
5010 /* #include "inftrees.h" */
5011 /* #include "infblock.h" */
5012 /* #include "infcodes.h" */
5013 /* #include "infutil.h" */
5014 /* #include "inffast.h" */
5016 #ifndef NO_DUMMY_DECL
5017 struct inflate_codes_state {int dummy;}; /* for buggy compilers */
5020 /* simplify the use of the inflate_huft type with some defines */
5021 #define base more.Base
5022 #define next more.Next
5023 #define exop word.what.Exop
5024 #define bits word.what.Bits
5026 /* macros for bit input with no checking and for returning unused bytes */
5027 #define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}}
5028 #define UNGRAB {n+=(c=k>>3);p-=c;k&=7;}
5030 /* Called with number of bytes left to write in window at least 258
5031 (the maximum string length) and number of input bytes available
5032 at least ten. The ten bytes are six bytes for the longest length/
5033 distance pair plus four bytes for overloading the bit buffer. */
5035 int inflate_fast(bl, bd, tl, td, s, z)
5038 inflate_huft *td; /* need separate declaration for Borland C++ */
5039 inflate_blocks_statef *s;
5042 inflate_huft *t; /* temporary pointer */
5043 uInt e; /* extra bits or operation */
5044 uLong b; /* bit buffer */
5045 uInt k; /* bits in bit buffer */
5046 Bytef *p; /* input data pointer */
5047 uInt n; /* bytes available there */
5048 Bytef *q; /* output window write pointer */
5049 uInt m; /* bytes to end of window or read pointer */
5050 uInt ml; /* mask for literal/length tree */
5051 uInt md; /* mask for distance tree */
5052 uInt c; /* bytes to copy */
5053 uInt d; /* distance back to copy from */
5054 Bytef *r; /* copy source pointer */
5056 /* load input, output, bit values */
5059 /* initialize masks */
5060 ml = inflate_mask[bl];
5061 md = inflate_mask[bd];
5063 /* do until not enough input or output space for fast loop */
5064 do { /* assume called with m >= 258 && n >= 10 */
5065 /* get literal/length code */
5066 GRABBITS(20) /* max bits for literal/length code */
5067 if ((e = (t = tl + ((uInt)b & ml))->exop) == 0)
5070 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5071 "inflate: * literal '%c'\n" :
5072 "inflate: * literal 0x%02x\n", t->base));
5073 *q++ = (Byte)t->base;
5081 /* get extra bits for length */
5083 c = t->base + ((uInt)b & inflate_mask[e]);
5085 Tracevv((stderr, "inflate: * length %u\n", c));
5087 /* decode distance base of block to copy */
5088 GRABBITS(15); /* max bits for distance code */
5089 e = (t = td + ((uInt)b & md))->exop;
5094 /* get extra bits to add to distance base */
5096 GRABBITS(e) /* get extra bits (up to 13) */
5097 d = t->base + ((uInt)b & inflate_mask[e]);
5099 Tracevv((stderr, "inflate: * distance %u\n", d));
5103 if ((uInt)(q - s->window) >= d) /* offset before dest */
5106 *q++ = *r++; c--; /* minimum count is three, */
5107 *q++ = *r++; c--; /* so unroll loop a little */
5109 else /* else offset after destination */
5111 e = d - (uInt)(q - s->window); /* bytes from offset to end */
5112 r = s->end - e; /* pointer to offset */
5113 if (c > e) /* if source crosses, */
5115 c -= e; /* copy to end of window */
5119 r = s->window; /* copy rest from start of window */
5122 do { /* copy all or what's left */
5127 else if ((e & 64) == 0)
5128 e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop;
5131 z->msg = (char*)"invalid distance code";
5134 return Z_DATA_ERROR;
5141 if ((e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop) == 0)
5144 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
5145 "inflate: * literal '%c'\n" :
5146 "inflate: * literal 0x%02x\n", t->base));
5147 *q++ = (Byte)t->base;
5154 Tracevv((stderr, "inflate: * end of block\n"));
5157 return Z_STREAM_END;
5161 z->msg = (char*)"invalid literal/length code";
5164 return Z_DATA_ERROR;
5167 } while (m >= 258 && n >= 10);
5169 /* not enough input or output--restore pointers and return */
5177 /* zutil.c -- target dependent utility functions for the compression library
5178 * Copyright (C) 1995-1996 Jean-loup Gailly.
5179 * For conditions of distribution and use, see copyright notice in zlib.h
5182 /* From: zutil.c,v 1.17 1996/07/24 13:41:12 me Exp $ */
5188 /* #include "zutil.h" */
5190 #ifndef NO_DUMMY_DECL
5191 struct internal_state {int dummy;}; /* for buggy compilers */
5195 extern void exit OF((int));
5198 static const char *z_errmsg[10] = {
5199 "need dictionary", /* Z_NEED_DICT 2 */
5200 "stream end", /* Z_STREAM_END 1 */
5202 "file error", /* Z_ERRNO (-1) */
5203 "stream error", /* Z_STREAM_ERROR (-2) */
5204 "data error", /* Z_DATA_ERROR (-3) */
5205 "insufficient memory", /* Z_MEM_ERROR (-4) */
5206 "buffer error", /* Z_BUF_ERROR (-5) */
5207 "incompatible version",/* Z_VERSION_ERROR (-6) */
5211 const char *zlibVersion()
5213 return ZLIB_VERSION;
5220 fprintf(stderr, "%s\n", m);
5227 void zmemcpy(dest, source, len)
5232 if (len == 0) return;
5234 *dest++ = *source++; /* ??? to be unrolled */
5235 } while (--len != 0);
5238 int zmemcmp(s1, s2, len)
5245 for (j = 0; j < len; j++) {
5246 if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
5251 void zmemzero(dest, len)
5255 if (len == 0) return;
5257 *dest++ = 0; /* ??? to be unrolled */
5258 } while (--len != 0);
5263 #if (defined( __BORLANDC__) || !defined(SMALL_MEDIUM)) && !defined(__32BIT__)
5264 /* Small and medium model in Turbo C are for now limited to near allocation
5265 * with reduced MAX_WBITS and MAX_MEM_LEVEL
5269 /* Turbo C malloc() does not allow dynamic allocation of 64K bytes
5270 * and farmalloc(64K) returns a pointer with an offset of 8, so we
5271 * must fix the pointer. Warning: the pointer must be put back to its
5272 * original form in order to free it, use zcfree().
5278 local int next_ptr = 0;
5280 typedef struct ptr_table_s {
5285 local ptr_table table[MAX_PTR];
5286 /* This table is used to remember the original form of pointers
5287 * to large buffers (64K). Such pointers are normalized with a zero offset.
5288 * Since MSDOS is not a preemptive multitasking OS, this table is not
5289 * protected from concurrent access. This hack doesn't work anyway on
5290 * a protected system like OS/2. Use Microsoft C instead.
5293 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5295 voidpf buf = opaque; /* just to make some compilers happy */
5296 ulg bsize = (ulg)items*size;
5298 /* If we allocate less than 65520 bytes, we assume that farmalloc
5299 * will return a usable pointer which doesn't have to be normalized.
5301 if (bsize < 65520L) {
5302 buf = farmalloc(bsize);
5303 if (*(ush*)&buf != 0) return buf;
5305 buf = farmalloc(bsize + 16L);
5307 if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
5308 table[next_ptr].org_ptr = buf;
5310 /* Normalize the pointer to seg:0 */
5311 *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
5313 table[next_ptr++].new_ptr = buf;
5317 void zcfree (voidpf opaque, voidpf ptr)
5320 if (*(ush*)&ptr != 0) { /* object < 64K */
5324 /* Find the original pointer */
5325 for (n = 0; n < next_ptr; n++) {
5326 if (ptr != table[n].new_ptr) continue;
5328 farfree(table[n].org_ptr);
5329 while (++n < next_ptr) {
5330 table[n-1] = table[n];
5335 ptr = opaque; /* just to make some compilers happy */
5336 Assert(0, "zcfree: ptr not found");
5339 #endif /* __TURBOC__ */
5342 #if defined(M_I86) && !defined(__32BIT__)
5343 /* Microsoft C in 16-bit mode */
5347 #if (!defined(_MSC_VER) || (_MSC_VER < 600))
5348 # define _halloc halloc
5349 # define _hfree hfree
5352 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
5354 if (opaque) opaque = 0; /* to make compiler happy */
5355 return _halloc((long)items, size);
5358 void zcfree (voidpf opaque, voidpf ptr)
5360 if (opaque) opaque = 0; /* to make compiler happy */
5367 #ifndef MY_ZCALLOC /* Any system without a special alloc function */
5370 extern voidp calloc OF((uInt items, uInt size));
5371 extern void free OF((voidpf ptr));
5374 voidpf zcalloc (opaque, items, size)
5379 if (opaque) items += size - size; /* make compiler happy */
5380 return (voidpf)calloc(items, size);
5383 void zcfree (opaque, ptr)
5388 if (opaque) return; /* make compiler happy */
5391 #endif /* MY_ZCALLOC */
5395 /* adler32.c -- compute the Adler-32 checksum of a data stream
5396 * Copyright (C) 1995-1996 Mark Adler
5397 * For conditions of distribution and use, see copyright notice in zlib.h
5400 /* From: adler32.c,v 1.10 1996/05/22 11:52:18 me Exp $ */
5402 /* #include "zlib.h" */
5404 #define BASE 65521L /* largest prime smaller than 65536 */
5406 /* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
5408 #define DO1(buf,i) {s1 += buf[i]; s2 += s1;}
5409 #define DO2(buf,i) DO1(buf,i); DO1(buf,i+1);
5410 #define DO4(buf,i) DO2(buf,i); DO2(buf,i+2);
5411 #define DO8(buf,i) DO4(buf,i); DO4(buf,i+4);
5412 #define DO16(buf) DO8(buf,0); DO8(buf,8);
5414 /* ========================================================================= */
5415 uLong adler32(adler, buf, len)
5420 unsigned long s1 = adler & 0xffff;
5421 unsigned long s2 = (adler >> 16) & 0xffff;
5424 if (buf == Z_NULL) return 1L;
5427 k = len < NMAX ? len : NMAX;
5441 return (s2 << 16) | s1;