2 * This file is derived from various .h and .c files from the zlib-1.0.4
3 * distribution by Jean-loup Gailly and Mark Adler, with some additions
4 * by Paul Mackerras to aid in implementing Deflate compression and
5 * decompression for PPP packets. See zlib.h for conditions of
6 * distribution and use.
8 * Changes that have been made include:
9 * - added Z_PACKET_FLUSH (see zlib.h for details)
10 * - added inflateIncomp and deflateOutputPending
11 * - allow strm->next_out to be NULL, meaning discard the output
13 * $FreeBSD: src/sys/net/zlib.c,v 1.10.2.3 2002/03/24 23:12:48 jedgar Exp $
14 * $DragonFly: src/sys/net/zlib.c,v 1.11 2007/01/07 00:41:29 dillon Exp $
18 * ==FILEVERSION 971210==
20 * This marker is used by the Linux installation script to determine
21 * whether an up-to-date version of this file is already installed.
28 #if (defined(__DragonFly__) || defined(__FreeBSD__)) && defined(_KERNEL)
29 #define inflate inflate_ppp /* FreeBSD already has an inflate :-( */
34 /* zutil.h -- internal interface and configuration of the compression library
35 * Copyright (C) 1995-1996 Jean-loup Gailly.
36 * For conditions of distribution and use, see copyright notice in zlib.h
39 /* WARNING: this file should *not* be used by applications. It is
40 part of the implementation of the compression library and is
41 subject to change. Applications should only use zlib.h.
44 /* From: zutil.h,v 1.16 1996/07/24 13:41:13 me Exp $ */
56 /* Assume this is a *BSD or SVR4 kernel */
57 #include <sys/param.h>
58 #include <sys/types.h>
60 #include <sys/systm.h>
61 #include <sys/module.h>
66 #if defined(__KERNEL__)
67 /* Assume this is a Linux kernel */
68 #include <linux/string.h>
71 #else /* not kernel */
73 #if defined(MSDOS)||defined(VMS)||defined(CRAY)||defined(WIN32)||defined(RISCOS)
83 #endif /* __KERNEL__ */
89 /* compile with -Dlocal if your debugger can't find static symbols */
91 typedef unsigned char uch
;
93 typedef unsigned short ush
;
95 typedef unsigned long ulg
;
97 static const char *z_errmsg
[10] = {
98 "need dictionary", /* Z_NEED_DICT 2 */
99 "stream end", /* Z_STREAM_END 1 */
101 "file error", /* Z_ERRNO (-1) */
102 "stream error", /* Z_STREAM_ERROR (-2) */
103 "data error", /* Z_DATA_ERROR (-3) */
104 "insufficient memory", /* Z_MEM_ERROR (-4) */
105 "buffer error", /* Z_BUF_ERROR (-5) */
106 "incompatible version",/* Z_VERSION_ERROR (-6) */
109 #define ERR_MSG(err) z_errmsg[Z_NEED_DICT-(err)]
111 #define ERR_RETURN(strm,err) \
112 return (strm->msg = (const char*)ERR_MSG(err), (err))
113 /* To be used only when the state is known to be valid */
115 /* common constants */
118 # define DEF_WBITS MAX_WBITS
120 /* default windowBits for decompression. MAX_WBITS is for compression only */
122 #if MAX_MEM_LEVEL >= 8
123 # define DEF_MEM_LEVEL 8
125 # define DEF_MEM_LEVEL MAX_MEM_LEVEL
127 /* default memLevel */
129 #define STORED_BLOCK 0
130 #define STATIC_TREES 1
132 /* The three kinds of block type */
135 #define MAX_MATCH 258
136 /* The minimum and maximum match lengths */
138 #define PRESET_DICT 0x20 /* preset dictionary flag in zlib header */
140 /* target dependencies */
143 # define OS_CODE 0x00
146 # else /* MSC or DJGPP */
152 # define OS_CODE 0x06
155 #ifdef WIN32 /* Window 95 & Windows NT */
156 # define OS_CODE 0x0b
159 #if defined(VAXC) || defined(VMS)
160 # define OS_CODE 0x02
161 # define FOPEN(name, mode) \
162 fopen((name), (mode), "mbc=60", "ctx=stm", "rfm=fix", "mrs=512")
166 # define OS_CODE 0x01
169 #if defined(ATARI) || defined(atarist)
170 # define OS_CODE 0x05
174 # define OS_CODE 0x07
177 #ifdef __50SERIES /* Prime/PRIMOS */
178 # define OS_CODE 0x0F
182 # define OS_CODE 0x0a
185 #if defined(_BEOS_) || defined(RISCOS)
186 # define fdopen(fd,mode) NULL /* No fdopen() */
189 /* Common defaults */
192 # define OS_CODE 0x03 /* assume Unix */
196 # define FOPEN(name, mode) fopen((name), (mode))
202 extern char *strerror
OF((int));
203 # define zstrerror(errnum) strerror(errnum)
205 # define zstrerror(errnum) ""
211 #if (defined(M_I86SM) || defined(M_I86MM)) && !defined(_MSC_VER)
212 /* Use our own functions for small and medium model with MSC <= 5.0.
213 * You may have to use the same strategy for Borland C (untested).
217 #if defined(STDC) && !defined(HAVE_MEMCPY) && !defined(NO_MEMCPY)
221 # ifdef SMALL_MEDIUM /* MSDOS small or medium model */
222 # define zmemcpy _fmemcpy
223 # define zmemcmp _fmemcmp
224 # define zmemzero(dest, len) _fmemset(dest, 0, len)
226 # define zmemcpy memcpy
227 # define zmemcmp memcmp
228 # define zmemzero(dest, len) memset(dest, 0, len)
231 extern void zmemcpy
OF((Bytef
* dest
, Bytef
* source
, uInt len
));
232 extern int zmemcmp
OF((Bytef
* s1
, Bytef
* s2
, uInt len
));
233 extern void zmemzero
OF((Bytef
* dest
, uInt len
));
236 /* Diagnostic functions */
242 extern void z_error
OF((char *m
));
243 # define Assert(cond,msg) {if(!(cond)) z_error(msg);}
244 # define Trace(x) fprintf x
245 # define Tracev(x) {if (verbose) fprintf x ;}
246 # define Tracevv(x) {if (verbose>1) fprintf x ;}
247 # define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
248 # define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
250 # define Assert(cond,msg)
255 # define Tracecv(c,x)
259 typedef uLong (*check_func
) OF((uLong check
, const Bytef
*buf
, uInt len
));
261 voidpf zcalloc
OF((voidpf opaque
, unsigned items
, unsigned size
));
262 void zcfree
OF((voidpf opaque
, voidpf ptr
));
264 #define ZALLOC(strm, items, size) \
265 (*((strm)->zalloc))((strm)->opaque, (items), (size))
266 #define ZFREE(strm, addr) (*((strm)->zfree))((strm)->opaque, (voidpf)(addr))
267 #define TRY_FREE(s, p) {if (p) ZFREE(s, p);}
269 #endif /* _Z_UTIL_H */
273 /* deflate.h -- internal compression state
274 * Copyright (C) 1995-1996 Jean-loup Gailly
275 * For conditions of distribution and use, see copyright notice in zlib.h
278 /* WARNING: this file should *not* be used by applications. It is
279 part of the implementation of the compression library and is
280 subject to change. Applications should only use zlib.h.
283 /* From: deflate.h,v 1.10 1996/07/02 12:41:00 me Exp $ */
288 /* #include "zutil.h" */
290 /* ===========================================================================
291 * Internal compression state.
294 #define LENGTH_CODES 29
295 /* number of length codes, not counting the special END_BLOCK code */
298 /* number of literal bytes 0..255 */
300 #define L_CODES (LITERALS+1+LENGTH_CODES)
301 /* number of Literal or Length codes, including the END_BLOCK code */
304 /* number of distance codes */
307 /* number of codes used to transfer the bit lengths */
309 #define HEAP_SIZE (2*L_CODES+1)
310 /* maximum heap size */
313 /* All codes must not exceed MAX_BITS bits */
315 #define INIT_STATE 42
316 #define BUSY_STATE 113
317 #define FINISH_STATE 666
321 /* Data structure describing a single value and its code string. */
322 typedef struct ct_data_s
{
324 ush freq
; /* frequency count */
325 ush code
; /* bit string */
328 ush dad
; /* father node in Huffman tree */
329 ush len
; /* length of bit string */
338 typedef struct static_tree_desc_s static_tree_desc
;
340 typedef struct tree_desc_s
{
341 ct_data
*dyn_tree
; /* the dynamic tree */
342 int max_code
; /* largest code with non zero frequency */
343 static_tree_desc
*stat_desc
; /* the corresponding static tree */
347 typedef Pos FAR Posf
;
348 typedef unsigned IPos
;
350 /* A Pos is an index in the character window. We use short instead of int to
351 * save space in the various tables. IPos is used only for parameter passing.
354 typedef struct deflate_state
{
355 z_streamp strm
; /* pointer back to this zlib stream */
356 int status
; /* as the name implies */
357 Bytef
*pending_buf
; /* output still pending */
358 ulg pending_buf_size
; /* size of pending_buf */
359 Bytef
*pending_out
; /* next pending byte to output to the stream */
360 int pending
; /* nb of bytes in the pending buffer */
361 int noheader
; /* suppress zlib header and adler32 */
362 Byte data_type
; /* UNKNOWN, BINARY or ASCII */
363 Byte method
; /* STORED (for zip only) or DEFLATED */
364 int last_flush
; /* value of flush param for previous deflate call */
366 /* used by deflate.c: */
368 uInt w_size
; /* LZ77 window size (32K by default) */
369 uInt w_bits
; /* log2(w_size) (8..16) */
370 uInt w_mask
; /* w_size - 1 */
373 /* Sliding window. Input bytes are read into the second half of the window,
374 * and move to the first half later to keep a dictionary of at least wSize
375 * bytes. With this organization, matches are limited to a distance of
376 * wSize-MAX_MATCH bytes, but this ensures that IO is always
377 * performed with a length multiple of the block size. Also, it limits
378 * the window size to 64K, which is quite useful on MSDOS.
379 * To do: use the user input buffer as sliding window.
383 /* Actual size of window: 2*wSize, except when the user input buffer
384 * is directly used as sliding window.
388 /* Link to older string with same hash index. To limit the size of this
389 * array to 64K, this link is maintained only for the last 32K strings.
390 * An index in this array is thus a window index modulo 32K.
393 Posf
*head
; /* Heads of the hash chains or NIL. */
395 uInt ins_h
; /* hash index of string to be inserted */
396 uInt hash_size
; /* number of elements in hash table */
397 uInt hash_bits
; /* log2(hash_size) */
398 uInt hash_mask
; /* hash_size-1 */
401 /* Number of bits by which ins_h must be shifted at each input
402 * step. It must be such that after MIN_MATCH steps, the oldest
403 * byte no longer takes part in the hash key, that is:
404 * hash_shift * MIN_MATCH >= hash_bits
408 /* Window position at the beginning of the current output block. Gets
409 * negative when the window is moved backwards.
412 uInt match_length
; /* length of best match */
413 IPos prev_match
; /* previous match */
414 int match_available
; /* set if previous match exists */
415 uInt strstart
; /* start of string to insert */
416 uInt match_start
; /* start of matching string */
417 uInt lookahead
; /* number of valid bytes ahead in window */
420 /* Length of the best match at previous step. Matches not greater than this
421 * are discarded. This is used in the lazy match evaluation.
424 uInt max_chain_length
;
425 /* To speed up deflation, hash chains are never searched beyond this
426 * length. A higher limit improves compression ratio but degrades the
431 /* Attempt to find a better match only when the current match is strictly
432 * smaller than this value. This mechanism is used only for compression
435 # define max_insert_length max_lazy_match
436 /* Insert new strings in the hash table only if the match length is not
437 * greater than this length. This saves time but degrades compression.
438 * max_insert_length is used only for compression levels <= 3.
441 int level
; /* compression level (1..9) */
442 int strategy
; /* favor or force Huffman coding*/
445 /* Use a faster search when the previous match is longer than this */
447 int nice_match
; /* Stop searching when current match exceeds this */
449 /* used by trees.c: */
450 /* Didn't use ct_data typedef below to supress compiler warning */
451 struct ct_data_s dyn_ltree
[HEAP_SIZE
]; /* literal and length tree */
452 struct ct_data_s dyn_dtree
[2*D_CODES
+1]; /* distance tree */
453 struct ct_data_s bl_tree
[2*BL_CODES
+1]; /* Huffman tree for bit lengths */
455 struct tree_desc_s l_desc
; /* desc. for literal tree */
456 struct tree_desc_s d_desc
; /* desc. for distance tree */
457 struct tree_desc_s bl_desc
; /* desc. for bit length tree */
459 ush bl_count
[MAX_BITS
+1];
460 /* number of codes at each bit length for an optimal tree */
462 int heap
[2*L_CODES
+1]; /* heap used to build the Huffman trees */
463 int heap_len
; /* number of elements in the heap */
464 int heap_max
; /* element of largest frequency */
465 /* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used.
466 * The same heap array is used to build all trees.
469 uch depth
[2*L_CODES
+1];
470 /* Depth of each subtree used as tie breaker for trees of equal frequency
473 uchf
*l_buf
; /* buffer for literals or lengths */
476 /* Size of match buffer for literals/lengths. There are 4 reasons for
477 * limiting lit_bufsize to 64K:
478 * - frequencies can be kept in 16 bit counters
479 * - if compression is not successful for the first block, all input
480 * data is still in the window so we can still emit a stored block even
481 * when input comes from standard input. (This can also be done for
482 * all blocks if lit_bufsize is not greater than 32K.)
483 * - if compression is not successful for a file smaller than 64K, we can
484 * even emit a stored file instead of a stored block (saving 5 bytes).
485 * This is applicable only for zip (not gzip or zlib).
486 * - creating new Huffman trees less frequently may not provide fast
487 * adaptation to changes in the input data statistics. (Take for
488 * example a binary file with poorly compressible code followed by
489 * a highly compressible string table.) Smaller buffer sizes give
490 * fast adaptation but have of course the overhead of transmitting
491 * trees more frequently.
492 * - I can't count above 4
495 uInt last_lit
; /* running index in l_buf */
498 /* Buffer for distances. To simplify the code, d_buf and l_buf have
499 * the same number of elements. To use different lengths, an extra flag
500 * array would be necessary.
503 ulg opt_len
; /* bit length of current block with optimal trees */
504 ulg static_len
; /* bit length of current block with static trees */
505 ulg compressed_len
; /* total bit length of compressed file */
506 uInt matches
; /* number of string matches in current block */
507 int last_eob_len
; /* bit length of EOB code for last block */
510 ulg bits_sent
; /* bit length of the compressed data */
514 /* Output buffer. bits are inserted starting at the bottom (least
518 /* Number of valid bits in bi_buf. All bits above the last valid bit
524 /* Output a byte on the stream.
525 * IN assertion: there is enough room in pending_buf.
527 #define put_byte(s, c) {s->pending_buf[s->pending++] = (c);}
530 #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
531 /* Minimum amount of lookahead, except at the end of the input file.
532 * See deflate.c for comments about the MIN_MATCH+1.
535 #define MAX_DIST(s) ((s)->w_size-MIN_LOOKAHEAD)
536 /* In order to simplify the code, particularly on 16 bit machines, match
537 * distances are limited to MAX_DIST instead of WSIZE.
541 void _tr_init
OF((deflate_state
*s
));
542 int _tr_tally
OF((deflate_state
*s
, unsigned dist
, unsigned lc
));
543 ulg _tr_flush_block
OF((deflate_state
*s
, charf
*buf
, ulg stored_len
,
545 void _tr_align
OF((deflate_state
*s
));
546 void _tr_stored_block
OF((deflate_state
*s
, charf
*buf
, ulg stored_len
,
548 void _tr_stored_type_only
OF((deflate_state
*));
554 /* deflate.c -- compress data using the deflation algorithm
555 * Copyright (C) 1995-1996 Jean-loup Gailly.
556 * For conditions of distribution and use, see copyright notice in zlib.h
562 * The "deflation" process depends on being able to identify portions
563 * of the input text which are identical to earlier input (within a
564 * sliding window trailing behind the input currently being processed).
566 * The most straightforward technique turns out to be the fastest for
567 * most input files: try all possible matches and select the longest.
568 * The key feature of this algorithm is that insertions into the string
569 * dictionary are very simple and thus fast, and deletions are avoided
570 * completely. Insertions are performed at each input character, whereas
571 * string matches are performed only when the previous match ends. So it
572 * is preferable to spend more time in matches to allow very fast string
573 * insertions and avoid deletions. The matching algorithm for small
574 * strings is inspired from that of Rabin & Karp. A brute force approach
575 * is used to find longer strings when a small match has been found.
576 * A similar algorithm is used in comic (by Jan-Mark Wams) and freeze
577 * (by Leonid Broukhis).
578 * A previous version of this file used a more sophisticated algorithm
579 * (by Fiala and Greene) which is guaranteed to run in linear amortized
580 * time, but has a larger average cost, uses more memory and is patented.
581 * However the F&G algorithm may be faster for some highly redundant
582 * files if the parameter max_chain_length (described below) is too large.
586 * The idea of lazy evaluation of matches is due to Jan-Mark Wams, and
587 * I found it in 'freeze' written by Leonid Broukhis.
588 * Thanks to many people for bug reports and testing.
592 * Deutsch, L.P.,"DEFLATE Compressed Data Format Specification".
593 * Available in ftp://ds.internic.net/rfc/rfc1951.txt
595 * A description of the Rabin and Karp algorithm is given in the book
596 * "Algorithms" by R. Sedgewick, Addison-Wesley, p252.
598 * Fiala,E.R., and Greene,D.H.
599 * Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595
603 /* From: deflate.c,v 1.15 1996/07/24 13:40:58 me Exp $ */
605 /* #include "deflate.h" */
607 char deflate_copyright
[] = " deflate 1.0.4 Copyright 1995-1996 Jean-loup Gailly ";
609 If you use the zlib library in a product, an acknowledgment is welcome
610 in the documentation of your product. If for some reason you cannot
611 include such an acknowledgment, I would appreciate that you keep this
612 copyright string in the executable of your product.
615 /* ===========================================================================
616 * Function prototypes.
619 need_more
, /* block not completed, need more input or more output */
620 block_done
, /* block flush performed */
621 finish_started
, /* finish started, need only more output at next deflate */
622 finish_done
/* finish done, accept no more input or output */
625 typedef block_state (*compress_func
) OF((deflate_state
*s
, int flush
));
626 /* Compression function. Returns the block state after the call. */
628 local
void fill_window
OF((deflate_state
*s
));
629 local block_state deflate_stored
OF((deflate_state
*s
, int flush
));
630 local block_state deflate_fast
OF((deflate_state
*s
, int flush
));
631 local block_state deflate_slow
OF((deflate_state
*s
, int flush
));
632 local
void lm_init
OF((deflate_state
*s
));
633 local
void putShortMSB
OF((deflate_state
*s
, uInt b
));
634 local
void flush_pending
OF((z_streamp strm
));
635 local
int read_buf
OF((z_streamp strm
, charf
*buf
, unsigned size
));
637 void match_init
OF((void)); /* asm code initialization */
638 uInt longest_match
OF((deflate_state
*s
, IPos cur_match
));
640 local uInt longest_match
OF((deflate_state
*s
, IPos cur_match
));
644 local
void check_match
OF((deflate_state
*s
, IPos start
, IPos match
,
648 /* ===========================================================================
653 /* Tail of hash chains */
656 # define TOO_FAR 4096
658 /* Matches of length 3 are discarded if their distance exceeds TOO_FAR */
660 #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
661 /* Minimum amount of lookahead, except at the end of the input file.
662 * See deflate.c for comments about the MIN_MATCH+1.
665 /* Values for max_lazy_match, good_match and max_chain_length, depending on
666 * the desired pack level (0..9). The values given below have been tuned to
667 * exclude worst case performance for pathological files. Better values may be
668 * found for specific files.
670 typedef struct config_s
{
671 ush good_length
; /* reduce lazy search above this match length */
672 ush max_lazy
; /* do not perform lazy search above this match length */
673 ush nice_length
; /* quit search above this match length */
678 local config configuration_table
[10] = {
679 /* good lazy nice chain */
680 /* 0 */ {0, 0, 0, 0, deflate_stored
}, /* store only */
681 /* 1 */ {4, 4, 8, 4, deflate_fast
}, /* maximum speed, no lazy matches */
682 /* 2 */ {4, 5, 16, 8, deflate_fast
},
683 /* 3 */ {4, 6, 32, 32, deflate_fast
},
685 /* 4 */ {4, 4, 16, 16, deflate_slow
}, /* lazy matches */
686 /* 5 */ {8, 16, 32, 32, deflate_slow
},
687 /* 6 */ {8, 16, 128, 128, deflate_slow
},
688 /* 7 */ {8, 32, 128, 256, deflate_slow
},
689 /* 8 */ {32, 128, 258, 1024, deflate_slow
},
690 /* 9 */ {32, 258, 258, 4096, deflate_slow
}}; /* maximum compression */
692 /* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4
693 * For deflate_fast() (levels <= 3) good is ignored and lazy has a different
698 /* result of memcmp for equal strings */
700 #ifndef NO_DUMMY_DECL
701 struct static_tree_desc_s
{int dummy
;}; /* for buggy compilers */
704 /* ===========================================================================
705 * Update a hash value with the given input byte
706 * IN assertion: all calls to to UPDATE_HASH are made with consecutive
707 * input characters, so that a running hash key can be computed from the
708 * previous key instead of complete recalculation each time.
710 #define UPDATE_HASH(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask)
713 /* ===========================================================================
714 * Insert string str in the dictionary and set match_head to the previous head
715 * of the hash chain (the most recent string with same hash key). Return
716 * the previous length of the hash chain.
717 * IN assertion: all calls to to INSERT_STRING are made with consecutive
718 * input characters and the first MIN_MATCH bytes of str are valid
719 * (except for the last MIN_MATCH-1 bytes of the input file).
721 #define INSERT_STRING(s, str, match_head) \
722 (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
723 s->prev[(str) & s->w_mask] = match_head = s->head[s->ins_h], \
724 s->head[s->ins_h] = (Pos)(str))
726 /* ===========================================================================
727 * Initialize the hash table (avoiding 64K overflow for 16 bit systems).
728 * prev[] will be initialized on the fly.
730 #define CLEAR_HASH(s) \
731 s->head[s->hash_size-1] = NIL; \
732 zmemzero((charf *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head));
734 /* ========================================================================= */
736 deflateInit_(z_streamp strm
, int level
, const char * version
,
739 return deflateInit2_(strm
, level
, Z_DEFLATED
, MAX_WBITS
, DEF_MEM_LEVEL
,
740 Z_DEFAULT_STRATEGY
, version
, stream_size
);
741 /* To do: ignore strm->next_in if we use it as window */
744 /* ========================================================================= */
746 deflateInit2_(z_streamp strm
, int level
, int method
, int windowBits
,
747 int memLevel
, int strategy
, const char *version
,
752 static char* my_version
= ZLIB_VERSION
;
755 /* We overlay pending_buf and d_buf+l_buf. This works since the average
756 * output size for (length,distance) codes is <= 24 bits.
759 if (version
== Z_NULL
|| version
[0] != my_version
[0] ||
760 stream_size
!= sizeof(z_stream
)) {
761 return Z_VERSION_ERROR
;
763 if (strm
== Z_NULL
) return Z_STREAM_ERROR
;
767 if (strm
->zalloc
== Z_NULL
) {
768 strm
->zalloc
= zcalloc
;
769 strm
->opaque
= (voidpf
)0;
771 if (strm
->zfree
== Z_NULL
) strm
->zfree
= zcfree
;
774 if (level
== Z_DEFAULT_COMPRESSION
) level
= 6;
776 if (windowBits
< 0) { /* undocumented feature: suppress zlib header */
778 windowBits
= -windowBits
;
780 if (memLevel
< 1 || memLevel
> MAX_MEM_LEVEL
|| method
!= Z_DEFLATED
||
781 windowBits
< 9 || windowBits
> 15 || level
< 0 || level
> 9 ||
782 strategy
< 0 || strategy
> Z_HUFFMAN_ONLY
) {
783 return Z_STREAM_ERROR
;
785 s
= (deflate_state
*) ZALLOC(strm
, 1, sizeof(deflate_state
));
786 if (s
== Z_NULL
) return Z_MEM_ERROR
;
787 strm
->state
= (struct internal_state FAR
*)s
;
790 s
->noheader
= noheader
;
791 s
->w_bits
= windowBits
;
792 s
->w_size
= 1 << s
->w_bits
;
793 s
->w_mask
= s
->w_size
- 1;
795 s
->hash_bits
= memLevel
+ 7;
796 s
->hash_size
= 1 << s
->hash_bits
;
797 s
->hash_mask
= s
->hash_size
- 1;
798 s
->hash_shift
= ((s
->hash_bits
+MIN_MATCH
-1)/MIN_MATCH
);
800 s
->window
= (Bytef
*) ZALLOC(strm
, s
->w_size
, 2*sizeof(Byte
));
801 s
->prev
= (Posf
*) ZALLOC(strm
, s
->w_size
, sizeof(Pos
));
802 s
->head
= (Posf
*) ZALLOC(strm
, s
->hash_size
, sizeof(Pos
));
804 s
->lit_bufsize
= 1 << (memLevel
+ 6); /* 16K elements by default */
806 overlay
= (ushf
*) ZALLOC(strm
, s
->lit_bufsize
, sizeof(ush
)+2);
807 s
->pending_buf
= (uchf
*) overlay
;
808 s
->pending_buf_size
= (ulg
)s
->lit_bufsize
* (sizeof(ush
)+2L);
810 if (s
->window
== Z_NULL
|| s
->prev
== Z_NULL
|| s
->head
== Z_NULL
||
811 s
->pending_buf
== Z_NULL
) {
812 strm
->msg
= (const char*)ERR_MSG(Z_MEM_ERROR
);
816 s
->d_buf
= overlay
+ s
->lit_bufsize
/sizeof(ush
);
817 s
->l_buf
= s
->pending_buf
+ (1+sizeof(ush
))*s
->lit_bufsize
;
820 s
->strategy
= strategy
;
821 s
->method
= (Byte
)method
;
823 return deflateReset(strm
);
826 /* ========================================================================= */
828 deflateSetDictionary(z_streamp strm
, const Bytef
*dictionary
, uInt dictLength
)
831 uInt length
= dictLength
;
835 if (strm
== Z_NULL
|| strm
->state
== Z_NULL
|| dictionary
== Z_NULL
)
836 return Z_STREAM_ERROR
;
838 s
= (deflate_state
*) strm
->state
;
839 if (s
->status
!= INIT_STATE
) return Z_STREAM_ERROR
;
841 strm
->adler
= adler32(strm
->adler
, dictionary
, dictLength
);
843 if (length
< MIN_MATCH
) return Z_OK
;
844 if (length
> MAX_DIST(s
)) {
845 length
= MAX_DIST(s
);
846 #ifndef USE_DICT_HEAD
847 dictionary
+= dictLength
- length
; /* use the tail of the dictionary */
850 zmemcpy((charf
*)s
->window
, dictionary
, length
);
851 s
->strstart
= length
;
852 s
->block_start
= (long)length
;
854 /* Insert all strings in the hash table (except for the last two bytes).
855 * s->lookahead stays null, so s->ins_h will be recomputed at the next
856 * call of fill_window.
858 s
->ins_h
= s
->window
[0];
859 UPDATE_HASH(s
, s
->ins_h
, s
->window
[1]);
860 for (n
= 0; n
<= length
- MIN_MATCH
; n
++) {
861 INSERT_STRING(s
, n
, hash_head
);
863 if (hash_head
) hash_head
= 0; /* to make compiler happy */
867 /* ========================================================================= */
869 deflateReset(z_streamp strm
)
873 if (strm
== Z_NULL
|| strm
->state
== Z_NULL
||
874 strm
->zalloc
== Z_NULL
|| strm
->zfree
== Z_NULL
) return Z_STREAM_ERROR
;
876 strm
->total_in
= strm
->total_out
= 0;
877 strm
->msg
= Z_NULL
; /* use zfree if we ever allocate msg dynamically */
878 strm
->data_type
= Z_UNKNOWN
;
880 s
= (deflate_state
*)strm
->state
;
882 s
->pending_out
= s
->pending_buf
;
884 if (s
->noheader
< 0) {
885 s
->noheader
= 0; /* was set to -1 by deflate(..., Z_FINISH); */
887 s
->status
= s
->noheader
? BUSY_STATE
: INIT_STATE
;
889 s
->last_flush
= Z_NO_FLUSH
;
897 /* ========================================================================= */
899 deflateParams(z_streamp strm
, int level
, int strategy
)
905 if (strm
== Z_NULL
|| strm
->state
== Z_NULL
) return Z_STREAM_ERROR
;
906 s
= (deflate_state
*) strm
->state
;
908 if (level
== Z_DEFAULT_COMPRESSION
) {
911 if (level
< 0 || level
> 9 || strategy
< 0 || strategy
> Z_HUFFMAN_ONLY
) {
912 return Z_STREAM_ERROR
;
914 func
= configuration_table
[s
->level
].func
;
916 if (func
!= configuration_table
[level
].func
&& strm
->total_in
!= 0) {
917 /* Flush the last buffer: */
918 err
= deflate(strm
, Z_PARTIAL_FLUSH
);
920 if (s
->level
!= level
) {
922 s
->max_lazy_match
= configuration_table
[level
].max_lazy
;
923 s
->good_match
= configuration_table
[level
].good_length
;
924 s
->nice_match
= configuration_table
[level
].nice_length
;
925 s
->max_chain_length
= configuration_table
[level
].max_chain
;
927 s
->strategy
= strategy
;
931 /* =========================================================================
932 * Put a short in the pending buffer. The 16-bit value is put in MSB order.
933 * IN assertion: the stream state is correct and there is enough room in
937 putShortMSB(deflate_state
*s
, uInt b
)
939 put_byte(s
, (Byte
)(b
>> 8));
940 put_byte(s
, (Byte
)(b
& 0xff));
943 /* =========================================================================
944 * Flush as much pending output as possible. All deflate() output goes
945 * through this function so some applications may wish to modify it
946 * to avoid allocating a large strm->next_out buffer and copying into it.
947 * (See also read_buf()).
950 flush_pending(z_streamp strm
)
952 deflate_state
*s
= (deflate_state
*) strm
->state
;
953 unsigned len
= s
->pending
;
955 if (len
> strm
->avail_out
) len
= strm
->avail_out
;
956 if (len
== 0) return;
958 if (strm
->next_out
!= Z_NULL
) {
959 zmemcpy(strm
->next_out
, s
->pending_out
, len
);
960 strm
->next_out
+= len
;
962 s
->pending_out
+= len
;
963 strm
->total_out
+= len
;
964 strm
->avail_out
-= len
;
966 if (s
->pending
== 0) {
967 s
->pending_out
= s
->pending_buf
;
971 /* ========================================================================= */
973 deflate(z_streamp strm
, int flush
)
975 int old_flush
; /* value of flush param for previous deflate call */
978 if (strm
== Z_NULL
|| strm
->state
== Z_NULL
||
979 flush
> Z_FINISH
|| flush
< 0) {
980 return Z_STREAM_ERROR
;
982 s
= (deflate_state
*) strm
->state
;
984 if ((strm
->next_in
== Z_NULL
&& strm
->avail_in
!= 0) ||
985 (s
->status
== FINISH_STATE
&& flush
!= Z_FINISH
)) {
986 ERR_RETURN(strm
, Z_STREAM_ERROR
);
988 if (strm
->avail_out
== 0) ERR_RETURN(strm
, Z_BUF_ERROR
);
990 s
->strm
= strm
; /* just in case */
991 old_flush
= s
->last_flush
;
992 s
->last_flush
= flush
;
994 /* Write the zlib header */
995 if (s
->status
== INIT_STATE
) {
997 uInt header
= (Z_DEFLATED
+ ((s
->w_bits
-8)<<4)) << 8;
998 uInt level_flags
= (s
->level
-1) >> 1;
1000 if (level_flags
> 3) level_flags
= 3;
1001 header
|= (level_flags
<< 6);
1002 if (s
->strstart
!= 0) header
|= PRESET_DICT
;
1003 header
+= 31 - (header
% 31);
1005 s
->status
= BUSY_STATE
;
1006 putShortMSB(s
, header
);
1008 /* Save the adler32 of the preset dictionary: */
1009 if (s
->strstart
!= 0) {
1010 putShortMSB(s
, (uInt
)(strm
->adler
>> 16));
1011 putShortMSB(s
, (uInt
)(strm
->adler
& 0xffff));
1016 /* Flush as much pending output as possible */
1017 if (s
->pending
!= 0) {
1018 flush_pending(strm
);
1019 if (strm
->avail_out
== 0) {
1020 /* Since avail_out is 0, deflate will be called again with
1021 * more output space, but possibly with both pending and
1022 * avail_in equal to zero. There won't be anything to do,
1023 * but this is not an error situation so make sure we
1024 * return OK instead of BUF_ERROR at next call of deflate:
1030 /* Make sure there is something to do and avoid duplicate consecutive
1031 * flushes. For repeated and useless calls with Z_FINISH, we keep
1032 * returning Z_STREAM_END instead of Z_BUFF_ERROR.
1034 } else if (strm
->avail_in
== 0 && flush
<= old_flush
&&
1035 flush
!= Z_FINISH
) {
1036 ERR_RETURN(strm
, Z_BUF_ERROR
);
1039 /* User must not provide more input after the first FINISH: */
1040 if (s
->status
== FINISH_STATE
&& strm
->avail_in
!= 0) {
1041 ERR_RETURN(strm
, Z_BUF_ERROR
);
1044 /* Start a new block or continue the current one.
1046 if (strm
->avail_in
!= 0 || s
->lookahead
!= 0 ||
1047 (flush
!= Z_NO_FLUSH
&& s
->status
!= FINISH_STATE
)) {
1050 bstate
= (*(configuration_table
[s
->level
].func
))(s
, flush
);
1052 if (bstate
== finish_started
|| bstate
== finish_done
) {
1053 s
->status
= FINISH_STATE
;
1055 if (bstate
== need_more
|| bstate
== finish_started
) {
1056 if (strm
->avail_out
== 0) {
1057 s
->last_flush
= -1; /* avoid BUF_ERROR next call, see above */
1060 /* If flush != Z_NO_FLUSH && avail_out == 0, the next call
1061 * of deflate should use the same flush parameter to make sure
1062 * that the flush is complete. So we don't have to output an
1063 * empty block here, this will be done at next call. This also
1064 * ensures that for a very small output buffer, we emit at most
1068 if (bstate
== block_done
) {
1069 if (flush
== Z_PARTIAL_FLUSH
) {
1071 } else if (flush
== Z_PACKET_FLUSH
) {
1072 /* Output just the 3-bit `stored' block type value,
1073 but not a zero length. */
1074 _tr_stored_type_only(s
);
1075 } else { /* FULL_FLUSH or SYNC_FLUSH */
1076 _tr_stored_block(s
, NULL
, 0L, 0);
1077 /* For a full flush, this empty block will be recognized
1078 * as a special marker by inflate_sync().
1080 if (flush
== Z_FULL_FLUSH
) {
1081 CLEAR_HASH(s
); /* forget history */
1084 flush_pending(strm
);
1085 if (strm
->avail_out
== 0) {
1086 s
->last_flush
= -1; /* avoid BUF_ERROR at next call, see above */
1091 Assert(strm
->avail_out
> 0, "bug2");
1093 if (flush
!= Z_FINISH
) return Z_OK
;
1094 if (s
->noheader
) return Z_STREAM_END
;
1096 /* Write the zlib trailer (adler32) */
1097 putShortMSB(s
, (uInt
)(strm
->adler
>> 16));
1098 putShortMSB(s
, (uInt
)(strm
->adler
& 0xffff));
1099 flush_pending(strm
);
1100 /* If avail_out is zero, the application will call deflate again
1101 * to flush the rest.
1103 s
->noheader
= -1; /* write the trailer only once! */
1104 return s
->pending
!= 0 ? Z_OK
: Z_STREAM_END
;
1107 /* ========================================================================= */
1109 deflateEnd(z_streamp strm
)
1114 if (strm
== Z_NULL
|| strm
->state
== Z_NULL
) return Z_STREAM_ERROR
;
1115 s
= (deflate_state
*) strm
->state
;
1118 if (status
!= INIT_STATE
&& status
!= BUSY_STATE
&&
1119 status
!= FINISH_STATE
) {
1120 return Z_STREAM_ERROR
;
1123 /* Deallocate in reverse order of allocations: */
1124 TRY_FREE(strm
, s
->pending_buf
);
1125 TRY_FREE(strm
, s
->head
);
1126 TRY_FREE(strm
, s
->prev
);
1127 TRY_FREE(strm
, s
->window
);
1130 strm
->state
= Z_NULL
;
1132 return status
== BUSY_STATE
? Z_DATA_ERROR
: Z_OK
;
1135 /* =========================================================================
1136 * Copy the source state to the destination state.
1139 deflateCopy(z_streamp dest
, z_streamp source
)
1145 if (source
== Z_NULL
|| dest
== Z_NULL
|| source
->state
== Z_NULL
)
1146 return Z_STREAM_ERROR
;
1147 ss
= (deflate_state
*) source
->state
;
1149 zmemcpy(dest
, source
, sizeof(*dest
));
1151 ds
= (deflate_state
*) ZALLOC(dest
, 1, sizeof(deflate_state
));
1152 if (ds
== Z_NULL
) return Z_MEM_ERROR
;
1153 dest
->state
= (struct internal_state FAR
*) ds
;
1154 zmemcpy(ds
, ss
, sizeof(*ds
));
1157 ds
->window
= (Bytef
*) ZALLOC(dest
, ds
->w_size
, 2*sizeof(Byte
));
1158 ds
->prev
= (Posf
*) ZALLOC(dest
, ds
->w_size
, sizeof(Pos
));
1159 ds
->head
= (Posf
*) ZALLOC(dest
, ds
->hash_size
, sizeof(Pos
));
1160 overlay
= (ushf
*) ZALLOC(dest
, ds
->lit_bufsize
, sizeof(ush
)+2);
1161 ds
->pending_buf
= (uchf
*) overlay
;
1163 if (ds
->window
== Z_NULL
|| ds
->prev
== Z_NULL
|| ds
->head
== Z_NULL
||
1164 ds
->pending_buf
== Z_NULL
) {
1168 /* ??? following zmemcpy doesn't work for 16-bit MSDOS */
1169 zmemcpy(ds
->window
, ss
->window
, ds
->w_size
* 2 * sizeof(Byte
));
1170 zmemcpy(ds
->prev
, ss
->prev
, ds
->w_size
* sizeof(Pos
));
1171 zmemcpy(ds
->head
, ss
->head
, ds
->hash_size
* sizeof(Pos
));
1172 zmemcpy(ds
->pending_buf
, ss
->pending_buf
, (uInt
)ds
->pending_buf_size
);
1174 ds
->pending_out
= ds
->pending_buf
+ (ss
->pending_out
- ss
->pending_buf
);
1175 ds
->d_buf
= overlay
+ ds
->lit_bufsize
/sizeof(ush
);
1176 ds
->l_buf
= ds
->pending_buf
+ (1+sizeof(ush
))*ds
->lit_bufsize
;
1178 ds
->l_desc
.dyn_tree
= ds
->dyn_ltree
;
1179 ds
->d_desc
.dyn_tree
= ds
->dyn_dtree
;
1180 ds
->bl_desc
.dyn_tree
= ds
->bl_tree
;
1185 /* ===========================================================================
1186 * Return the number of bytes of output which are immediately available
1187 * for output from the decompressor.
1190 deflateOutputPending(z_streamp strm
)
1192 if (strm
== Z_NULL
|| strm
->state
== Z_NULL
) return 0;
1194 return ((deflate_state
*)(strm
->state
))->pending
;
1197 /* ===========================================================================
1198 * Read a new buffer from the current input stream, update the adler32
1199 * and total number of bytes read. All deflate() input goes through
1200 * this function so some applications may wish to modify it to avoid
1201 * allocating a large strm->next_in buffer and copying from it.
1202 * (See also flush_pending()).
1205 read_buf(z_streamp strm
, charf
*buf
, unsigned size
)
1207 unsigned len
= strm
->avail_in
;
1209 if (len
> size
) len
= size
;
1210 if (len
== 0) return 0;
1212 strm
->avail_in
-= len
;
1214 if (!((deflate_state
*)(strm
->state
))->noheader
) {
1215 strm
->adler
= adler32(strm
->adler
, strm
->next_in
, len
);
1217 zmemcpy(buf
, strm
->next_in
, len
);
1218 strm
->next_in
+= len
;
1219 strm
->total_in
+= len
;
1224 /* ===========================================================================
1225 * Initialize the "longest match" routines for a new zlib stream
1228 lm_init(deflate_state
*s
)
1230 s
->window_size
= (ulg
)2L*s
->w_size
;
1234 /* Set the default configuration parameters:
1236 s
->max_lazy_match
= configuration_table
[s
->level
].max_lazy
;
1237 s
->good_match
= configuration_table
[s
->level
].good_length
;
1238 s
->nice_match
= configuration_table
[s
->level
].nice_length
;
1239 s
->max_chain_length
= configuration_table
[s
->level
].max_chain
;
1242 s
->block_start
= 0L;
1244 s
->match_length
= s
->prev_length
= MIN_MATCH
-1;
1245 s
->match_available
= 0;
1248 match_init(); /* initialize the asm code */
1252 /* ===========================================================================
1253 * Set match_start to the longest match starting at the given string and
1254 * return its length. Matches shorter or equal to prev_length are discarded,
1255 * in which case the result is equal to prev_length and match_start is
1257 * IN assertions: cur_match is the head of the hash chain for the current
1258 * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
1259 * OUT assertion: the match length is not greater than s->lookahead.
1262 * cur_match: current match
1265 /* For 80x86 and 680x0, an optimized version will be provided in match.asm or
1266 * match.S. The code will be functionally equivalent.
1269 longest_match(deflate_state
*s
, IPos cur_match
)
1271 unsigned chain_length
= s
->max_chain_length
;/* max hash chain length */
1272 Bytef
*scan
= s
->window
+ s
->strstart
; /* current string */
1273 Bytef
*match
; /* matched string */
1274 int len
; /* length of current match */
1275 int best_len
= s
->prev_length
; /* best match length so far */
1276 int nice_match
= s
->nice_match
; /* stop if match long enough */
1277 IPos limit
= s
->strstart
> (IPos
)MAX_DIST(s
) ?
1278 s
->strstart
- (IPos
)MAX_DIST(s
) : NIL
;
1279 /* Stop when cur_match becomes <= limit. To simplify the code,
1280 * we prevent matches with the string of window index 0.
1282 Posf
*prev
= s
->prev
;
1283 uInt wmask
= s
->w_mask
;
1286 /* Compare two bytes at a time. Note: this is not always beneficial.
1287 * Try with and without -DUNALIGNED_OK to check.
1289 Bytef
*strend
= s
->window
+ s
->strstart
+ MAX_MATCH
- 1;
1290 ush scan_start
= *(ushf
*)scan
;
1291 ush scan_end
= *(ushf
*)(scan
+best_len
-1);
1293 Bytef
*strend
= s
->window
+ s
->strstart
+ MAX_MATCH
;
1294 Byte scan_end1
= scan
[best_len
-1];
1295 Byte scan_end
= scan
[best_len
];
1298 /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
1299 * It is easy to get rid of this optimization if necessary.
1301 Assert(s
->hash_bits
>= 8 && MAX_MATCH
== 258, "Code too clever");
1303 /* Do not waste too much time if we already have a good match: */
1304 if (s
->prev_length
>= s
->good_match
) {
1307 /* Do not look for matches beyond the end of the input. This is necessary
1308 * to make deflate deterministic.
1310 if ((uInt
)nice_match
> s
->lookahead
) nice_match
= s
->lookahead
;
1312 Assert((ulg
)s
->strstart
<= s
->window_size
-MIN_LOOKAHEAD
, "need lookahead");
1315 Assert(cur_match
< s
->strstart
, "no future");
1316 match
= s
->window
+ cur_match
;
1318 /* Skip to next match if the match length cannot increase
1319 * or if the match length is less than 2:
1321 #if (defined(UNALIGNED_OK) && MAX_MATCH == 258)
1322 /* This code assumes sizeof(unsigned short) == 2. Do not use
1323 * UNALIGNED_OK if your compiler uses a different size.
1325 if (*(ushf
*)(match
+best_len
-1) != scan_end
||
1326 *(ushf
*)match
!= scan_start
) continue;
1328 /* It is not necessary to compare scan[2] and match[2] since they are
1329 * always equal when the other bytes match, given that the hash keys
1330 * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at
1331 * strstart+3, +5, ... up to strstart+257. We check for insufficient
1332 * lookahead only every 4th comparison; the 128th check will be made
1333 * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is
1334 * necessary to put more guard bytes at the end of the window, or
1335 * to check more often for insufficient lookahead.
1337 Assert(scan
[2] == match
[2], "scan[2]?");
1340 } while (*(ushf
*)(scan
+=2) == *(ushf
*)(match
+=2) &&
1341 *(ushf
*)(scan
+=2) == *(ushf
*)(match
+=2) &&
1342 *(ushf
*)(scan
+=2) == *(ushf
*)(match
+=2) &&
1343 *(ushf
*)(scan
+=2) == *(ushf
*)(match
+=2) &&
1345 /* The funny "do {}" generates better code on most compilers */
1347 /* Here, scan <= window+strstart+257 */
1348 Assert(scan
<= s
->window
+(unsigned)(s
->window_size
-1), "wild scan");
1349 if (*scan
== *match
) scan
++;
1351 len
= (MAX_MATCH
- 1) - (int)(strend
-scan
);
1352 scan
= strend
- (MAX_MATCH
-1);
1354 #else /* UNALIGNED_OK */
1356 if (match
[best_len
] != scan_end
||
1357 match
[best_len
-1] != scan_end1
||
1359 *++match
!= scan
[1]) continue;
1361 /* The check at best_len-1 can be removed because it will be made
1362 * again later. (This heuristic is not always a win.)
1363 * It is not necessary to compare scan[2] and match[2] since they
1364 * are always equal when the other bytes match, given that
1365 * the hash keys are equal and that HASH_BITS >= 8.
1368 Assert(*scan
== *match
, "match[2]?");
1370 /* We check for insufficient lookahead only every 8th comparison;
1371 * the 256th check will be made at strstart+258.
1374 } while (*++scan
== *++match
&& *++scan
== *++match
&&
1375 *++scan
== *++match
&& *++scan
== *++match
&&
1376 *++scan
== *++match
&& *++scan
== *++match
&&
1377 *++scan
== *++match
&& *++scan
== *++match
&&
1380 Assert(scan
<= s
->window
+(unsigned)(s
->window_size
-1), "wild scan");
1382 len
= MAX_MATCH
- (int)(strend
- scan
);
1383 scan
= strend
- MAX_MATCH
;
1385 #endif /* UNALIGNED_OK */
1387 if (len
> best_len
) {
1388 s
->match_start
= cur_match
;
1390 if (len
>= nice_match
) break;
1392 scan_end
= *(ushf
*)(scan
+best_len
-1);
1394 scan_end1
= scan
[best_len
-1];
1395 scan_end
= scan
[best_len
];
1398 } while ((cur_match
= prev
[cur_match
& wmask
]) > limit
1399 && --chain_length
!= 0);
1401 if ((uInt
)best_len
<= s
->lookahead
) return best_len
;
1402 return s
->lookahead
;
1407 /* ===========================================================================
1408 * Check that the match at match_start is indeed a match.
1411 check_match(deflate_state
*s
, IPos start
, IPos match
, int length
)
1413 /* check that the match is indeed a match */
1414 if (zmemcmp((charf
*)s
->window
+ match
,
1415 (charf
*)s
->window
+ start
, length
) != EQUAL
) {
1416 fprintf(stderr
, " start %u, match %u, length %d\n",
1417 start
, match
, length
);
1419 fprintf(stderr
, "%c%c", s
->window
[match
++], s
->window
[start
++]);
1420 } while (--length
!= 0);
1421 z_error("invalid match");
1423 if (z_verbose
> 1) {
1424 fprintf(stderr
,"\\[%d,%d]", start
-match
, length
);
1425 do { putc(s
->window
[start
++], stderr
); } while (--length
!= 0);
1429 # define check_match(s, start, match, length)
1432 /* ===========================================================================
1433 * Fill the window when the lookahead becomes insufficient.
1434 * Updates strstart and lookahead.
1436 * IN assertion: lookahead < MIN_LOOKAHEAD
1437 * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD
1438 * At least one byte has been read, or avail_in == 0; reads are
1439 * performed for at least two bytes (required for the zip translate_eol
1440 * option -- not supported here).
1443 fill_window(deflate_state
*s
)
1447 unsigned more
; /* Amount of free space at the end of the window. */
1448 uInt wsize
= s
->w_size
;
1451 more
= (unsigned)(s
->window_size
-(ulg
)s
->lookahead
-(ulg
)s
->strstart
);
1453 /* Deal with !@#$% 64K limit: */
1454 if (more
== 0 && s
->strstart
== 0 && s
->lookahead
== 0) {
1457 } else if (more
== (unsigned)(-1)) {
1458 /* Very unlikely, but possible on 16 bit machine if strstart == 0
1459 * and lookahead == 1 (input done one byte at time)
1463 /* If the window is almost full and there is insufficient lookahead,
1464 * move the upper half to the lower one to make room in the upper half.
1466 } else if (s
->strstart
>= wsize
+MAX_DIST(s
)) {
1468 zmemcpy((charf
*)s
->window
, (charf
*)s
->window
+wsize
,
1470 s
->match_start
-= wsize
;
1471 s
->strstart
-= wsize
; /* we now have strstart >= MAX_DIST */
1472 s
->block_start
-= (long) wsize
;
1474 /* Slide the hash table (could be avoided with 32 bit values
1475 at the expense of memory usage). We slide even when level == 0
1476 to keep the hash table consistent if we switch back to level > 0
1477 later. (Using level 0 permanently is not an optimal usage of
1478 zlib, so we don't care about this pathological case.)
1484 *p
= (Pos
)(m
>= wsize
? m
-wsize
: NIL
);
1491 *p
= (Pos
)(m
>= wsize
? m
-wsize
: NIL
);
1492 /* If n is not on any hash chain, prev[n] is garbage but
1493 * its value will never be used.
1498 if (s
->strm
->avail_in
== 0) return;
1500 /* If there was no sliding:
1501 * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 &&
1502 * more == window_size - lookahead - strstart
1503 * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1)
1504 * => more >= window_size - 2*WSIZE + 2
1505 * In the BIG_MEM or MMAP case (not yet supported),
1506 * window_size == input_size + MIN_LOOKAHEAD &&
1507 * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD.
1508 * Otherwise, window_size == 2*WSIZE so more >= 2.
1509 * If there was sliding, more >= WSIZE. So in all cases, more >= 2.
1511 Assert(more
>= 2, "more < 2");
1513 n
= read_buf(s
->strm
, (charf
*)s
->window
+ s
->strstart
+ s
->lookahead
,
1517 /* Initialize the hash value now that we have some input: */
1518 if (s
->lookahead
>= MIN_MATCH
) {
1519 s
->ins_h
= s
->window
[s
->strstart
];
1520 UPDATE_HASH(s
, s
->ins_h
, s
->window
[s
->strstart
+1]);
1522 Call
UPDATE_HASH() MIN_MATCH
-3 more times
1525 /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage,
1526 * but this is not important since only literal bytes will be emitted.
1529 } while (s
->lookahead
< MIN_LOOKAHEAD
&& s
->strm
->avail_in
!= 0);
1532 /* ===========================================================================
1533 * Flush the current block, with given end-of-file flag.
1534 * IN assertion: strstart is set to the end of the current match.
1536 #define FLUSH_BLOCK_ONLY(s, eof) { \
1537 _tr_flush_block(s, (s->block_start >= 0L ? \
1538 (charf *)&s->window[(unsigned)s->block_start] : \
1540 (ulg)((long)s->strstart - s->block_start), \
1542 s->block_start = s->strstart; \
1543 flush_pending(s->strm); \
1544 Tracev((stderr,"[FLUSH]")); \
1547 /* Same but force premature exit if necessary. */
1548 #define FLUSH_BLOCK(s, eof) { \
1549 FLUSH_BLOCK_ONLY(s, eof); \
1550 if (s->strm->avail_out == 0) return (eof) ? finish_started : need_more; \
1553 /* ===========================================================================
1554 * Copy without compression as much as possible from the input stream, return
1555 * the current block state.
1556 * This function does not insert new strings in the dictionary since
1557 * uncompressible data is probably not useful. This function is used
1558 * only for the level=0 compression option.
1559 * NOTE: this function should be optimized to avoid extra copying from
1560 * window to pending_buf.
1563 deflate_stored(deflate_state
*s
, int flush
)
1565 /* Stored blocks are limited to 0xffff bytes, pending_buf is limited
1566 * to pending_buf_size, and each stored block has a 5 byte header:
1568 ulg max_block_size
= 0xffff;
1571 if (max_block_size
> s
->pending_buf_size
- 5) {
1572 max_block_size
= s
->pending_buf_size
- 5;
1575 /* Copy as much as possible from input to output: */
1577 /* Fill the window as much as possible: */
1578 if (s
->lookahead
<= 1) {
1580 Assert(s
->strstart
< s
->w_size
+MAX_DIST(s
) ||
1581 s
->block_start
>= (long)s
->w_size
, "slide too late");
1584 if (s
->lookahead
== 0 && flush
== Z_NO_FLUSH
) return need_more
;
1586 if (s
->lookahead
== 0) break; /* flush the current block */
1588 Assert(s
->block_start
>= 0L, "block gone");
1590 s
->strstart
+= s
->lookahead
;
1593 /* Emit a stored block if pending_buf will be full: */
1594 max_start
= s
->block_start
+ max_block_size
;
1595 if (s
->strstart
== 0 || (ulg
)s
->strstart
>= max_start
) {
1596 /* strstart == 0 is possible when wraparound on 16-bit machine */
1597 s
->lookahead
= (uInt
)(s
->strstart
- max_start
);
1598 s
->strstart
= (uInt
)max_start
;
1601 /* Flush if we may have to slide, otherwise block_start may become
1602 * negative and the data will be gone:
1604 if (s
->strstart
- (uInt
)s
->block_start
>= MAX_DIST(s
)) {
1608 FLUSH_BLOCK(s
, flush
== Z_FINISH
);
1609 return flush
== Z_FINISH
? finish_done
: block_done
;
1612 /* ===========================================================================
1613 * Compress as much as possible from the input stream, return the current
1615 * This function does not perform lazy evaluation of matches and inserts
1616 * new strings in the dictionary only for unmatched strings or for short
1617 * matches. It is used only for the fast compression options.
1620 deflate_fast(deflate_state
*s
, int flush
)
1622 IPos hash_head
= NIL
; /* head of the hash chain */
1623 int bflush
; /* set if current block must be flushed */
1626 /* Make sure that we always have enough lookahead, except
1627 * at the end of the input file. We need MAX_MATCH bytes
1628 * for the next match, plus MIN_MATCH bytes to insert the
1629 * string following the next match.
1631 if (s
->lookahead
< MIN_LOOKAHEAD
) {
1633 if (s
->lookahead
< MIN_LOOKAHEAD
&& flush
== Z_NO_FLUSH
) {
1636 if (s
->lookahead
== 0) break; /* flush the current block */
1639 /* Insert the string window[strstart .. strstart+2] in the
1640 * dictionary, and set hash_head to the head of the hash chain:
1642 if (s
->lookahead
>= MIN_MATCH
) {
1643 INSERT_STRING(s
, s
->strstart
, hash_head
);
1646 /* Find the longest match, discarding those <= prev_length.
1647 * At this point we have always match_length < MIN_MATCH
1649 if (hash_head
!= NIL
&& s
->strstart
- hash_head
<= MAX_DIST(s
)) {
1650 /* To simplify the code, we prevent matches with the string
1651 * of window index 0 (in particular we have to avoid a match
1652 * of the string with itself at the start of the input file).
1654 if (s
->strategy
!= Z_HUFFMAN_ONLY
) {
1655 s
->match_length
= longest_match (s
, hash_head
);
1657 /* longest_match() sets match_start */
1659 if (s
->match_length
>= MIN_MATCH
) {
1660 check_match(s
, s
->strstart
, s
->match_start
, s
->match_length
);
1662 bflush
= _tr_tally(s
, s
->strstart
- s
->match_start
,
1663 s
->match_length
- MIN_MATCH
);
1665 s
->lookahead
-= s
->match_length
;
1667 /* Insert new strings in the hash table only if the match length
1668 * is not too large. This saves time but degrades compression.
1670 if (s
->match_length
<= s
->max_insert_length
&&
1671 s
->lookahead
>= MIN_MATCH
) {
1672 s
->match_length
--; /* string at strstart already in hash table */
1675 INSERT_STRING(s
, s
->strstart
, hash_head
);
1676 /* strstart never exceeds WSIZE-MAX_MATCH, so there are
1677 * always MIN_MATCH bytes ahead.
1679 } while (--s
->match_length
!= 0);
1682 s
->strstart
+= s
->match_length
;
1683 s
->match_length
= 0;
1684 s
->ins_h
= s
->window
[s
->strstart
];
1685 UPDATE_HASH(s
, s
->ins_h
, s
->window
[s
->strstart
+1]);
1687 Call
UPDATE_HASH() MIN_MATCH
-3 more times
1689 /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not
1690 * matter since it will be recomputed at next deflate call.
1694 /* No match, output a literal byte */
1695 Tracevv((stderr
,"%c", s
->window
[s
->strstart
]));
1696 bflush
= _tr_tally (s
, 0, s
->window
[s
->strstart
]);
1700 if (bflush
) FLUSH_BLOCK(s
, 0);
1702 FLUSH_BLOCK(s
, flush
== Z_FINISH
);
1703 return flush
== Z_FINISH
? finish_done
: block_done
;
1706 /* ===========================================================================
1707 * Same as above, but achieves better compression. We use a lazy
1708 * evaluation for matches: a match is finally adopted only if there is
1709 * no better match at the next window position.
1712 deflate_slow(deflate_state
*s
, int flush
)
1714 IPos hash_head
= NIL
; /* head of hash chain */
1715 int bflush
; /* set if current block must be flushed */
1717 /* Process the input block. */
1719 /* Make sure that we always have enough lookahead, except
1720 * at the end of the input file. We need MAX_MATCH bytes
1721 * for the next match, plus MIN_MATCH bytes to insert the
1722 * string following the next match.
1724 if (s
->lookahead
< MIN_LOOKAHEAD
) {
1726 if (s
->lookahead
< MIN_LOOKAHEAD
&& flush
== Z_NO_FLUSH
) {
1729 if (s
->lookahead
== 0) break; /* flush the current block */
1732 /* Insert the string window[strstart .. strstart+2] in the
1733 * dictionary, and set hash_head to the head of the hash chain:
1735 if (s
->lookahead
>= MIN_MATCH
) {
1736 INSERT_STRING(s
, s
->strstart
, hash_head
);
1739 /* Find the longest match, discarding those <= prev_length.
1741 s
->prev_length
= s
->match_length
, s
->prev_match
= s
->match_start
;
1742 s
->match_length
= MIN_MATCH
-1;
1744 if (hash_head
!= NIL
&& s
->prev_length
< s
->max_lazy_match
&&
1745 s
->strstart
- hash_head
<= MAX_DIST(s
)) {
1746 /* To simplify the code, we prevent matches with the string
1747 * of window index 0 (in particular we have to avoid a match
1748 * of the string with itself at the start of the input file).
1750 if (s
->strategy
!= Z_HUFFMAN_ONLY
) {
1751 s
->match_length
= longest_match (s
, hash_head
);
1753 /* longest_match() sets match_start */
1755 if (s
->match_length
<= 5 && (s
->strategy
== Z_FILTERED
||
1756 (s
->match_length
== MIN_MATCH
&&
1757 s
->strstart
- s
->match_start
> TOO_FAR
))) {
1759 /* If prev_match is also MIN_MATCH, match_start is garbage
1760 * but we will ignore the current match anyway.
1762 s
->match_length
= MIN_MATCH
-1;
1765 /* If there was a match at the previous step and the current
1766 * match is not better, output the previous match:
1768 if (s
->prev_length
>= MIN_MATCH
&& s
->match_length
<= s
->prev_length
) {
1769 uInt max_insert
= s
->strstart
+ s
->lookahead
- MIN_MATCH
;
1770 /* Do not insert strings in hash table beyond this. */
1772 check_match(s
, s
->strstart
-1, s
->prev_match
, s
->prev_length
);
1774 bflush
= _tr_tally(s
, s
->strstart
-1 - s
->prev_match
,
1775 s
->prev_length
- MIN_MATCH
);
1777 /* Insert in hash table all strings up to the end of the match.
1778 * strstart-1 and strstart are already inserted. If there is not
1779 * enough lookahead, the last two strings are not inserted in
1782 s
->lookahead
-= s
->prev_length
-1;
1783 s
->prev_length
-= 2;
1785 if (++s
->strstart
<= max_insert
) {
1786 INSERT_STRING(s
, s
->strstart
, hash_head
);
1788 } while (--s
->prev_length
!= 0);
1789 s
->match_available
= 0;
1790 s
->match_length
= MIN_MATCH
-1;
1793 if (bflush
) FLUSH_BLOCK(s
, 0);
1795 } else if (s
->match_available
) {
1796 /* If there was no match at the previous position, output a
1797 * single literal. If there was a match but the current match
1798 * is longer, truncate the previous match to a single literal.
1800 Tracevv((stderr
,"%c", s
->window
[s
->strstart
-1]));
1801 if (_tr_tally (s
, 0, s
->window
[s
->strstart
-1])) {
1802 FLUSH_BLOCK_ONLY(s
, 0);
1806 if (s
->strm
->avail_out
== 0) return need_more
;
1808 /* There is no previous match to compare with, wait for
1809 * the next step to decide.
1811 s
->match_available
= 1;
1816 Assert (flush
!= Z_NO_FLUSH
, "no flush?");
1817 if (s
->match_available
) {
1818 Tracevv((stderr
,"%c", s
->window
[s
->strstart
-1]));
1819 _tr_tally (s
, 0, s
->window
[s
->strstart
-1]);
1820 s
->match_available
= 0;
1822 FLUSH_BLOCK(s
, flush
== Z_FINISH
);
1823 return flush
== Z_FINISH
? finish_done
: block_done
;
1828 /* trees.c -- output deflated data using Huffman coding
1829 * Copyright (C) 1995-1996 Jean-loup Gailly
1830 * For conditions of distribution and use, see copyright notice in zlib.h
1836 * The "deflation" process uses several Huffman trees. The more
1837 * common source values are represented by shorter bit sequences.
1839 * Each code tree is stored in a compressed form which is itself
1840 * a Huffman encoding of the lengths of all the code strings (in
1841 * ascending order by source values). The actual code strings are
1842 * reconstructed from the lengths in the inflate process, as described
1843 * in the deflate specification.
1847 * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification".
1848 * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc
1851 * Data Compression: Methods and Theory, pp. 49-50.
1852 * Computer Science Press, 1988. ISBN 0-7167-8156-5.
1856 * Addison-Wesley, 1983. ISBN 0-201-06672-6.
1859 /* From: trees.c,v 1.11 1996/07/24 13:41:06 me Exp $ */
1861 /* #include "deflate.h" */
1867 /* ===========================================================================
1871 #define MAX_BL_BITS 7
1872 /* Bit length codes must not exceed MAX_BL_BITS bits */
1874 #define END_BLOCK 256
1875 /* end of block literal code */
1878 /* repeat previous bit length 3-6 times (2 bits of repeat count) */
1880 #define REPZ_3_10 17
1881 /* repeat a zero length 3-10 times (3 bits of repeat count) */
1883 #define REPZ_11_138 18
1884 /* repeat a zero length 11-138 times (7 bits of repeat count) */
1886 local
int extra_lbits
[LENGTH_CODES
] /* extra bits for each length code */
1887 = {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};
1889 local
int extra_dbits
[D_CODES
] /* extra bits for each distance code */
1890 = {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};
1892 local
int extra_blbits
[BL_CODES
]/* extra bits for each bit length code */
1893 = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};
1895 local uch bl_order
[BL_CODES
]
1896 = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};
1897 /* The lengths of the bit length codes are sent in order of decreasing
1898 * probability, to avoid transmitting the lengths for unused bit length codes.
1901 #define Buf_size (8 * 2*sizeof(char))
1902 /* Number of bits used within bi_buf. (bi_buf might be implemented on
1903 * more than 16 bits on some systems.)
1906 /* ===========================================================================
1907 * Local data. These are initialized only once.
1910 local ct_data static_ltree
[L_CODES
+2];
1911 /* The static literal tree. Since the bit lengths are imposed, there is no
1912 * need for the L_CODES extra codes used during heap construction. However
1913 * The codes 286 and 287 are needed to build a canonical tree (see _tr_init
1917 local ct_data static_dtree
[D_CODES
];
1918 /* The static distance tree. (Actually a trivial tree since all codes use
1922 local uch dist_code
[512];
1923 /* distance codes. The first 256 values correspond to the distances
1924 * 3 .. 258, the last 256 values correspond to the top 8 bits of
1925 * the 15 bit distances.
1928 local uch length_code
[MAX_MATCH
-MIN_MATCH
+1];
1929 /* length code for each normalized match length (0 == MIN_MATCH) */
1931 local
int base_length
[LENGTH_CODES
];
1932 /* First normalized length for each code (0 = MIN_MATCH) */
1934 local
int base_dist
[D_CODES
];
1935 /* First normalized distance for each code (0 = distance of 1) */
1937 struct static_tree_desc_s
{
1938 ct_data
*static_tree
; /* static tree or NULL */
1939 intf
*extra_bits
; /* extra bits for each code or NULL */
1940 int extra_base
; /* base index for extra_bits */
1941 int elems
; /* max number of elements in the tree */
1942 int max_length
; /* max bit length for the codes */
1945 local static_tree_desc static_l_desc
=
1946 {static_ltree
, extra_lbits
, LITERALS
+1, L_CODES
, MAX_BITS
};
1948 local static_tree_desc static_d_desc
=
1949 {static_dtree
, extra_dbits
, 0, D_CODES
, MAX_BITS
};
1951 local static_tree_desc static_bl_desc
=
1952 {NULL
, extra_blbits
, 0, BL_CODES
, MAX_BL_BITS
};
1954 /* ===========================================================================
1955 * Local (static) routines in this file.
1958 local
void tr_static_init
OF((void));
1959 local
void init_block
OF((deflate_state
*s
));
1960 local
void pqdownheap
OF((deflate_state
*s
, ct_data
*tree
, int k
));
1961 local
void gen_bitlen
OF((deflate_state
*s
, tree_desc
*desc
));
1962 local
void gen_codes
OF((ct_data
*tree
, int max_code
, ushf
*bl_count
));
1963 local
void build_tree
OF((deflate_state
*s
, tree_desc
*desc
));
1964 local
void scan_tree
OF((deflate_state
*s
, ct_data
*tree
, int max_code
));
1965 local
void send_tree
OF((deflate_state
*s
, ct_data
*tree
, int max_code
));
1966 local
int build_bl_tree
OF((deflate_state
*s
));
1967 local
void send_all_trees
OF((deflate_state
*s
, int lcodes
, int dcodes
,
1969 local
void compress_block
OF((deflate_state
*s
, ct_data
*ltree
,
1971 local
void set_data_type
OF((deflate_state
*s
));
1972 local
unsigned bi_reverse
OF((unsigned value
, int length
));
1973 local
void bi_windup
OF((deflate_state
*s
));
1974 local
void bi_flush
OF((deflate_state
*s
));
1975 local
void copy_block
OF((deflate_state
*s
, charf
*buf
, unsigned len
,
1979 # define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len)
1980 /* Send a code of the given tree. c and tree must not have side effects */
1982 #else /* DEBUG_ZLIB */
1983 # define send_code(s, c, tree) \
1984 { if (verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \
1985 send_bits(s, tree[c].Code, tree[c].Len); }
1988 #define d_code(dist) \
1989 ((dist) < 256 ? dist_code[dist] : dist_code[256+((dist)>>7)])
1990 /* Mapping from a distance to a distance code. dist is the distance - 1 and
1991 * must not have side effects. dist_code[256] and dist_code[257] are never
1995 /* ===========================================================================
1996 * Output a short LSB first on the stream.
1997 * IN assertion: there is enough room in pendingBuf.
1999 #define put_short(s, w) { \
2000 put_byte(s, (uch)((w) & 0xff)); \
2001 put_byte(s, (uch)((ush)(w) >> 8)); \
2004 /* ===========================================================================
2005 * Send a value on a given number of bits.
2006 * IN assertion: length <= 16 and value fits in length bits.
2009 * value: value to send
2010 * length: number of bits
2013 local
void send_bits
OF((deflate_state
*s
, int value
, int length
));
2016 send_bits(deflate_state
*s
, int value
, int length
)
2018 Tracevv((stderr
," l %2d v %4x ", length
, value
));
2019 Assert(length
> 0 && length
<= 15, "invalid length");
2020 s
->bits_sent
+= (ulg
)length
;
2022 /* If not enough room in bi_buf, use (valid) bits from bi_buf and
2023 * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
2024 * unused bits in value.
2026 if (s
->bi_valid
> (int)Buf_size
- length
) {
2027 s
->bi_buf
|= (value
<< s
->bi_valid
);
2028 put_short(s
, s
->bi_buf
);
2029 s
->bi_buf
= (ush
)value
>> (Buf_size
- s
->bi_valid
);
2030 s
->bi_valid
+= length
- Buf_size
;
2032 s
->bi_buf
|= value
<< s
->bi_valid
;
2033 s
->bi_valid
+= length
;
2036 #else /* !DEBUG_ZLIB */
2038 #define send_bits(s, value, length) \
2039 { int len = length;\
2040 if (s->bi_valid > (int)Buf_size - len) {\
2042 s->bi_buf |= (val << s->bi_valid);\
2043 put_short(s, s->bi_buf);\
2044 s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\
2045 s->bi_valid += len - Buf_size;\
2047 s->bi_buf |= (value) << s->bi_valid;\
2048 s->bi_valid += len;\
2051 #endif /* DEBUG_ZLIB */
2053 /* the arguments must not have side effects */
2055 /* ===========================================================================
2056 * Initialize the various 'constant' tables. In a multi-threaded environment,
2057 * this function may be called by two threads concurrently, but this is
2058 * harmless since both invocations do exactly the same thing.
2061 tr_static_init(void)
2063 static int static_init_done
= 0;
2064 int n
; /* iterates over tree elements */
2065 int bits
; /* bit counter */
2066 int length
; /* length value */
2067 int code
; /* code value */
2068 int dist
; /* distance index */
2069 ush bl_count
[MAX_BITS
+1];
2070 /* number of codes at each bit length for an optimal tree */
2072 if (static_init_done
) return;
2074 /* Initialize the mapping length (0..255) -> length code (0..28) */
2076 for (code
= 0; code
< LENGTH_CODES
-1; code
++) {
2077 base_length
[code
] = length
;
2078 for (n
= 0; n
< (1<<extra_lbits
[code
]); n
++) {
2079 length_code
[length
++] = (uch
)code
;
2082 Assert (length
== 256, "tr_static_init: length != 256");
2083 /* Note that the length 255 (match length 258) can be represented
2084 * in two different ways: code 284 + 5 bits or code 285, so we
2085 * overwrite length_code[255] to use the best encoding:
2087 length_code
[length
-1] = (uch
)code
;
2089 /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
2091 for (code
= 0 ; code
< 16; code
++) {
2092 base_dist
[code
] = dist
;
2093 for (n
= 0; n
< (1<<extra_dbits
[code
]); n
++) {
2094 dist_code
[dist
++] = (uch
)code
;
2097 Assert (dist
== 256, "tr_static_init: dist != 256");
2098 dist
>>= 7; /* from now on, all distances are divided by 128 */
2099 for ( ; code
< D_CODES
; code
++) {
2100 base_dist
[code
] = dist
<< 7;
2101 for (n
= 0; n
< (1<<(extra_dbits
[code
]-7)); n
++) {
2102 dist_code
[256 + dist
++] = (uch
)code
;
2105 Assert (dist
== 256, "tr_static_init: 256+dist != 512");
2107 /* Construct the codes of the static literal tree */
2108 for (bits
= 0; bits
<= MAX_BITS
; bits
++) bl_count
[bits
] = 0;
2110 while (n
<= 143) static_ltree
[n
++].Len
= 8, bl_count
[8]++;
2111 while (n
<= 255) static_ltree
[n
++].Len
= 9, bl_count
[9]++;
2112 while (n
<= 279) static_ltree
[n
++].Len
= 7, bl_count
[7]++;
2113 while (n
<= 287) static_ltree
[n
++].Len
= 8, bl_count
[8]++;
2114 /* Codes 286 and 287 do not exist, but we must include them in the
2115 * tree construction to get a canonical Huffman tree (longest code
2118 gen_codes((ct_data
*)static_ltree
, L_CODES
+1, bl_count
);
2120 /* The static distance tree is trivial: */
2121 for (n
= 0; n
< D_CODES
; n
++) {
2122 static_dtree
[n
].Len
= 5;
2123 static_dtree
[n
].Code
= bi_reverse((unsigned)n
, 5);
2125 static_init_done
= 1;
2128 /* ===========================================================================
2129 * Initialize the tree data structures for a new zlib stream.
2132 _tr_init(deflate_state
*s
)
2136 s
->compressed_len
= 0L;
2138 s
->l_desc
.dyn_tree
= s
->dyn_ltree
;
2139 s
->l_desc
.stat_desc
= &static_l_desc
;
2141 s
->d_desc
.dyn_tree
= s
->dyn_dtree
;
2142 s
->d_desc
.stat_desc
= &static_d_desc
;
2144 s
->bl_desc
.dyn_tree
= s
->bl_tree
;
2145 s
->bl_desc
.stat_desc
= &static_bl_desc
;
2149 s
->last_eob_len
= 8; /* enough lookahead for inflate */
2154 /* Initialize the first block of the first file: */
2158 /* ===========================================================================
2159 * Initialize a new block.
2162 init_block(deflate_state
*s
)
2164 int n
; /* iterates over tree elements */
2166 /* Initialize the trees. */
2167 for (n
= 0; n
< L_CODES
; n
++) s
->dyn_ltree
[n
].Freq
= 0;
2168 for (n
= 0; n
< D_CODES
; n
++) s
->dyn_dtree
[n
].Freq
= 0;
2169 for (n
= 0; n
< BL_CODES
; n
++) s
->bl_tree
[n
].Freq
= 0;
2171 s
->dyn_ltree
[END_BLOCK
].Freq
= 1;
2172 s
->opt_len
= s
->static_len
= 0L;
2173 s
->last_lit
= s
->matches
= 0;
2177 /* Index within the heap array of least frequent node in the Huffman tree */
2180 /* ===========================================================================
2181 * Remove the smallest element from the heap and recreate the heap with
2182 * one less element. Updates heap and heap_len.
2184 #define pqremove(s, tree, top) \
2186 top = s->heap[SMALLEST]; \
2187 s->heap[SMALLEST] = s->heap[s->heap_len--]; \
2188 pqdownheap(s, tree, SMALLEST); \
2191 /* ===========================================================================
2192 * Compares to subtrees, using the tree depth as tie breaker when
2193 * the subtrees have equal frequency. This minimizes the worst case length.
2195 #define smaller(tree, n, m, depth) \
2196 (tree[n].Freq < tree[m].Freq || \
2197 (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m]))
2199 /* ===========================================================================
2200 * Restore the heap property by moving down the tree starting at node k,
2201 * exchanging a node with the smallest of its two sons if necessary, stopping
2202 * when the heap property is re-established (each father smaller than its
2206 * tree: the tree to restore
2207 * k: node to move down
2210 pqdownheap(deflate_state
*s
, ct_data
*tree
, int k
)
2213 int j
= k
<< 1; /* left son of k */
2214 while (j
<= s
->heap_len
) {
2215 /* Set j to the smallest of the two sons: */
2216 if (j
< s
->heap_len
&&
2217 smaller(tree
, s
->heap
[j
+1], s
->heap
[j
], s
->depth
)) {
2220 /* Exit if v is smaller than both sons */
2221 if (smaller(tree
, v
, s
->heap
[j
], s
->depth
)) break;
2223 /* Exchange v with the smallest son */
2224 s
->heap
[k
] = s
->heap
[j
]; k
= j
;
2226 /* And continue down the tree, setting j to the left son of k */
2232 /* ===========================================================================
2233 * Compute the optimal bit lengths for a tree and update the total bit length
2234 * for the current block.
2235 * IN assertion: the fields freq and dad are set, heap[heap_max] and
2236 * above are the tree nodes sorted by increasing frequency.
2237 * OUT assertions: the field len is set to the optimal bit length, the
2238 * array bl_count contains the frequencies for each bit length.
2239 * The length opt_len is updated; static_len is also updated if stree is
2243 * desc: the tree descriptor
2246 gen_bitlen(deflate_state
*s
, tree_desc
*desc
)
2248 ct_data
*tree
= desc
->dyn_tree
;
2249 int max_code
= desc
->max_code
;
2250 ct_data
*stree
= desc
->stat_desc
->static_tree
;
2251 intf
*extra
= desc
->stat_desc
->extra_bits
;
2252 int base
= desc
->stat_desc
->extra_base
;
2253 int max_length
= desc
->stat_desc
->max_length
;
2254 int h
; /* heap index */
2255 int n
, m
; /* iterate over the tree elements */
2256 int bits
; /* bit length */
2257 int xbits
; /* extra bits */
2258 ush f
; /* frequency */
2259 int overflow
= 0; /* number of elements with bit length too large */
2261 for (bits
= 0; bits
<= MAX_BITS
; bits
++) s
->bl_count
[bits
] = 0;
2263 /* In a first pass, compute the optimal bit lengths (which may
2264 * overflow in the case of the bit length tree).
2266 tree
[s
->heap
[s
->heap_max
]].Len
= 0; /* root of the heap */
2268 for (h
= s
->heap_max
+1; h
< HEAP_SIZE
; h
++) {
2270 bits
= tree
[tree
[n
].Dad
].Len
+ 1;
2271 if (bits
> max_length
) bits
= max_length
, overflow
++;
2272 tree
[n
].Len
= (ush
)bits
;
2273 /* We overwrite tree[n].Dad which is no longer needed */
2275 if (n
> max_code
) continue; /* not a leaf node */
2277 s
->bl_count
[bits
]++;
2279 if (n
>= base
) xbits
= extra
[n
-base
];
2281 s
->opt_len
+= (ulg
)f
* (bits
+ xbits
);
2282 if (stree
) s
->static_len
+= (ulg
)f
* (stree
[n
].Len
+ xbits
);
2284 if (overflow
== 0) return;
2286 Trace((stderr
,"\nbit length overflow\n"));
2287 /* This happens for example on obj2 and pic of the Calgary corpus */
2289 /* Find the first bit length which could increase: */
2291 bits
= max_length
-1;
2292 while (s
->bl_count
[bits
] == 0) bits
--;
2293 s
->bl_count
[bits
]--; /* move one leaf down the tree */
2294 s
->bl_count
[bits
+1] += 2; /* move one overflow item as its brother */
2295 s
->bl_count
[max_length
]--;
2296 /* The brother of the overflow item also moves one step up,
2297 * but this does not affect bl_count[max_length]
2300 } while (overflow
> 0);
2302 /* Now recompute all bit lengths, scanning in increasing frequency.
2303 * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
2304 * lengths instead of fixing only the wrong ones. This idea is taken
2305 * from 'ar' written by Haruhiko Okumura.)
2307 for (bits
= max_length
; bits
!= 0; bits
--) {
2308 n
= s
->bl_count
[bits
];
2311 if (m
> max_code
) continue;
2312 if (tree
[m
].Len
!= (unsigned) bits
) {
2313 Trace((stderr
,"code %d bits %d->%d\n", m
, tree
[m
].Len
, bits
));
2314 s
->opt_len
+= ((long)bits
- (long)tree
[m
].Len
)
2315 *(long)tree
[m
].Freq
;
2316 tree
[m
].Len
= (ush
)bits
;
2323 /* ===========================================================================
2324 * Generate the codes for a given tree and bit counts (which need not be
2326 * IN assertion: the array bl_count contains the bit length statistics for
2327 * the given tree and the field len is set for all tree elements.
2328 * OUT assertion: the field code is set for all tree elements of non
2332 * tree: the tree to decorate
2333 * max_code: largest code with non zero frequency
2334 * bl_count: number of codes at each bit length
2337 gen_codes(ct_data
*tree
, int max_code
, ushf
*bl_count
)
2339 ush next_code
[MAX_BITS
+1]; /* next code value for each bit length */
2340 ush code
= 0; /* running code value */
2341 int bits
; /* bit index */
2342 int n
; /* code index */
2344 /* The distribution counts are first used to generate the code values
2345 * without bit reversal.
2347 for (bits
= 1; bits
<= MAX_BITS
; bits
++) {
2348 next_code
[bits
] = code
= (code
+ bl_count
[bits
-1]) << 1;
2350 /* Check that the bit counts in bl_count are consistent. The last code
2353 Assert (code
+ bl_count
[MAX_BITS
]-1 == (1<<MAX_BITS
)-1,
2354 "inconsistent bit counts");
2355 Tracev((stderr
,"\ngen_codes: max_code %d ", max_code
));
2357 for (n
= 0; n
<= max_code
; n
++) {
2358 int len
= tree
[n
].Len
;
2359 if (len
== 0) continue;
2360 /* Now reverse the bits */
2361 tree
[n
].Code
= bi_reverse(next_code
[len
]++, len
);
2363 Tracecv(tree
!= static_ltree
, (stderr
,"\nn %3d %c l %2d c %4x (%x) ",
2364 n
, (isgraph(n
) ? n
: ' '), len
, tree
[n
].Code
, next_code
[len
]-1));
2368 /* ===========================================================================
2369 * Construct one Huffman tree and assigns the code bit strings and lengths.
2370 * Update the total bit length for the current block.
2371 * IN assertion: the field freq is set for all tree elements.
2372 * OUT assertions: the fields len and code are set to the optimal bit length
2373 * and corresponding code. The length opt_len is updated; static_len is
2374 * also updated if stree is not null. The field max_code is set.
2377 * desc: the tree descriptor
2380 build_tree(deflate_state
*s
, tree_desc
*desc
)
2382 ct_data
*tree
= desc
->dyn_tree
;
2383 ct_data
*stree
= desc
->stat_desc
->static_tree
;
2384 int elems
= desc
->stat_desc
->elems
;
2385 int n
, m
; /* iterate over heap elements */
2386 int max_code
= -1; /* largest code with non zero frequency */
2387 int node
; /* new node being created */
2389 /* Construct the initial heap, with least frequent element in
2390 * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
2391 * heap[0] is not used.
2393 s
->heap_len
= 0, s
->heap_max
= HEAP_SIZE
;
2395 for (n
= 0; n
< elems
; n
++) {
2396 if (tree
[n
].Freq
!= 0) {
2397 s
->heap
[++(s
->heap_len
)] = max_code
= n
;
2404 /* The pkzip format requires that at least one distance code exists,
2405 * and that at least one bit should be sent even if there is only one
2406 * possible code. So to avoid special checks later on we force at least
2407 * two codes of non zero frequency.
2409 while (s
->heap_len
< 2) {
2410 node
= s
->heap
[++(s
->heap_len
)] = (max_code
< 2 ? ++max_code
: 0);
2411 tree
[node
].Freq
= 1;
2413 s
->opt_len
--; if (stree
) s
->static_len
-= stree
[node
].Len
;
2414 /* node is 0 or 1 so it does not have extra bits */
2416 desc
->max_code
= max_code
;
2418 /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
2419 * establish sub-heaps of increasing lengths:
2421 for (n
= s
->heap_len
/2; n
>= 1; n
--) pqdownheap(s
, tree
, n
);
2423 /* Construct the Huffman tree by repeatedly combining the least two
2426 node
= elems
; /* next internal node of the tree */
2428 pqremove(s
, tree
, n
); /* n = node of least frequency */
2429 m
= s
->heap
[SMALLEST
]; /* m = node of next least frequency */
2431 s
->heap
[--(s
->heap_max
)] = n
; /* keep the nodes sorted by frequency */
2432 s
->heap
[--(s
->heap_max
)] = m
;
2434 /* Create a new node father of n and m */
2435 tree
[node
].Freq
= tree
[n
].Freq
+ tree
[m
].Freq
;
2436 s
->depth
[node
] = (uch
) (MAX(s
->depth
[n
], s
->depth
[m
]) + 1);
2437 tree
[n
].Dad
= tree
[m
].Dad
= (ush
)node
;
2439 if (tree
== s
->bl_tree
) {
2440 fprintf(stderr
,"\nnode %d(%d), sons %d(%d) %d(%d)",
2441 node
, tree
[node
].Freq
, n
, tree
[n
].Freq
, m
, tree
[m
].Freq
);
2444 /* and insert the new node in the heap */
2445 s
->heap
[SMALLEST
] = node
++;
2446 pqdownheap(s
, tree
, SMALLEST
);
2448 } while (s
->heap_len
>= 2);
2450 s
->heap
[--(s
->heap_max
)] = s
->heap
[SMALLEST
];
2452 /* At this point, the fields freq and dad are set. We can now
2453 * generate the bit lengths.
2455 gen_bitlen(s
, (tree_desc
*)desc
);
2457 /* The field len is now set, we can generate the bit codes */
2458 gen_codes ((ct_data
*)tree
, max_code
, s
->bl_count
);
2461 /* ===========================================================================
2462 * Scan a literal or distance tree to determine the frequencies of the codes
2463 * in the bit length tree.
2466 * tree: the tree to be scanned
2467 * max_code: and its largest code of non zero frequency
2470 scan_tree (deflate_state
*s
, ct_data
*tree
, int max_code
)
2472 int n
; /* iterates over all tree elements */
2473 int prevlen
= -1; /* last emitted length */
2474 int curlen
; /* length of current code */
2475 int nextlen
= tree
[0].Len
; /* length of next code */
2476 int count
= 0; /* repeat count of the current code */
2477 int max_count
= 7; /* max repeat count */
2478 int min_count
= 4; /* min repeat count */
2480 if (nextlen
== 0) max_count
= 138, min_count
= 3;
2481 tree
[max_code
+1].Len
= (ush
)0xffff; /* guard */
2483 for (n
= 0; n
<= max_code
; n
++) {
2484 curlen
= nextlen
; nextlen
= tree
[n
+1].Len
;
2485 if (++count
< max_count
&& curlen
== nextlen
) {
2487 } else if (count
< min_count
) {
2488 s
->bl_tree
[curlen
].Freq
+= count
;
2489 } else if (curlen
!= 0) {
2490 if (curlen
!= prevlen
) s
->bl_tree
[curlen
].Freq
++;
2491 s
->bl_tree
[REP_3_6
].Freq
++;
2492 } else if (count
<= 10) {
2493 s
->bl_tree
[REPZ_3_10
].Freq
++;
2495 s
->bl_tree
[REPZ_11_138
].Freq
++;
2497 count
= 0; prevlen
= curlen
;
2499 max_count
= 138, min_count
= 3;
2500 } else if (curlen
== nextlen
) {
2501 max_count
= 6, min_count
= 3;
2503 max_count
= 7, min_count
= 4;
2508 /* ===========================================================================
2509 * Send a literal or distance tree in compressed form, using the codes in
2513 * tree: the tree to be scanned
2514 * max_code: and its largest code of non zero frequency
2517 send_tree(deflate_state
*s
, ct_data
*tree
, int max_code
)
2519 int n
; /* iterates over all tree elements */
2520 int prevlen
= -1; /* last emitted length */
2521 int curlen
; /* length of current code */
2522 int nextlen
= tree
[0].Len
; /* length of next code */
2523 int count
= 0; /* repeat count of the current code */
2524 int max_count
= 7; /* max repeat count */
2525 int min_count
= 4; /* min repeat count */
2527 /* tree[max_code+1].Len = -1; */ /* guard already set */
2528 if (nextlen
== 0) max_count
= 138, min_count
= 3;
2530 for (n
= 0; n
<= max_code
; n
++) {
2531 curlen
= nextlen
; nextlen
= tree
[n
+1].Len
;
2532 if (++count
< max_count
&& curlen
== nextlen
) {
2534 } else if (count
< min_count
) {
2535 do { send_code(s
, curlen
, s
->bl_tree
); } while (--count
!= 0);
2537 } else if (curlen
!= 0) {
2538 if (curlen
!= prevlen
) {
2539 send_code(s
, curlen
, s
->bl_tree
); count
--;
2541 Assert(count
>= 3 && count
<= 6, " 3_6?");
2542 send_code(s
, REP_3_6
, s
->bl_tree
); send_bits(s
, count
-3, 2);
2544 } else if (count
<= 10) {
2545 send_code(s
, REPZ_3_10
, s
->bl_tree
); send_bits(s
, count
-3, 3);
2548 send_code(s
, REPZ_11_138
, s
->bl_tree
); send_bits(s
, count
-11, 7);
2550 count
= 0; prevlen
= curlen
;
2552 max_count
= 138, min_count
= 3;
2553 } else if (curlen
== nextlen
) {
2554 max_count
= 6, min_count
= 3;
2556 max_count
= 7, min_count
= 4;
2561 /* ===========================================================================
2562 * Construct the Huffman tree for the bit lengths and return the index in
2563 * bl_order of the last bit length code to send.
2566 build_bl_tree(deflate_state
*s
)
2568 int max_blindex
; /* index of last bit length code of non zero freq */
2570 /* Determine the bit length frequencies for literal and distance trees */
2571 scan_tree(s
, (ct_data
*)s
->dyn_ltree
, s
->l_desc
.max_code
);
2572 scan_tree(s
, (ct_data
*)s
->dyn_dtree
, s
->d_desc
.max_code
);
2574 /* Build the bit length tree: */
2575 build_tree(s
, (tree_desc
*)(&(s
->bl_desc
)));
2576 /* opt_len now includes the length of the tree representations, except
2577 * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
2580 /* Determine the number of bit length codes to send. The pkzip format
2581 * requires that at least 4 bit length codes be sent. (appnote.txt says
2582 * 3 but the actual value used is 4.)
2584 for (max_blindex
= BL_CODES
-1; max_blindex
>= 3; max_blindex
--) {
2585 if (s
->bl_tree
[bl_order
[max_blindex
]].Len
!= 0) break;
2587 /* Update opt_len to include the bit length tree and counts */
2588 s
->opt_len
+= 3*(max_blindex
+1) + 5+5+4;
2589 Tracev((stderr
, "\ndyn trees: dyn %ld, stat %ld",
2590 s
->opt_len
, s
->static_len
));
2595 /* ===========================================================================
2596 * Send the header for a block using dynamic Huffman trees: the counts, the
2597 * lengths of the bit length codes, the literal tree and the distance tree.
2598 * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
2601 * lcodes, dcodes, blcodes: number of codes for each tree
2604 send_all_trees(deflate_state
*s
, int lcodes
, int dcodes
, int blcodes
)
2606 int rank
; /* index in bl_order */
2608 Assert (lcodes
>= 257 && dcodes
>= 1 && blcodes
>= 4, "not enough codes");
2609 Assert (lcodes
<= L_CODES
&& dcodes
<= D_CODES
&& blcodes
<= BL_CODES
,
2611 Tracev((stderr
, "\nbl counts: "));
2612 send_bits(s
, lcodes
-257, 5); /* not +255 as stated in appnote.txt */
2613 send_bits(s
, dcodes
-1, 5);
2614 send_bits(s
, blcodes
-4, 4); /* not -3 as stated in appnote.txt */
2615 for (rank
= 0; rank
< blcodes
; rank
++) {
2616 Tracev((stderr
, "\nbl code %2d ", bl_order
[rank
]));
2617 send_bits(s
, s
->bl_tree
[bl_order
[rank
]].Len
, 3);
2619 Tracev((stderr
, "\nbl tree: sent %ld", s
->bits_sent
));
2621 send_tree(s
, (ct_data
*)s
->dyn_ltree
, lcodes
-1); /* literal tree */
2622 Tracev((stderr
, "\nlit tree: sent %ld", s
->bits_sent
));
2624 send_tree(s
, (ct_data
*)s
->dyn_dtree
, dcodes
-1); /* distance tree */
2625 Tracev((stderr
, "\ndist tree: sent %ld", s
->bits_sent
));
2628 /* ===========================================================================
2629 * Send a stored block
2633 * stored_len: length of input block
2634 * eof: true if this is the last block for a file
2637 _tr_stored_block(deflate_state
*s
, charf
*buf
, ulg stored_len
, int eof
)
2639 send_bits(s
, (STORED_BLOCK
<<1)+eof
, 3); /* send block type */
2640 s
->compressed_len
= (s
->compressed_len
+ 3 + 7) & (ulg
)~7L;
2641 s
->compressed_len
+= (stored_len
+ 4) << 3;
2643 copy_block(s
, buf
, (unsigned)stored_len
, 1); /* with header */
2646 /* Send just the `stored block' type code without any length bytes or data.
2649 _tr_stored_type_only(deflate_state
*s
)
2651 send_bits(s
, (STORED_BLOCK
<< 1), 3);
2653 s
->compressed_len
= (s
->compressed_len
+ 3) & ~7L;
2657 /* ===========================================================================
2658 * Send one empty static block to give enough lookahead for inflate.
2659 * This takes 10 bits, of which 7 may remain in the bit buffer.
2660 * The current inflate code requires 9 bits of lookahead. If the
2661 * last two codes for the previous block (real code plus EOB) were coded
2662 * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode
2663 * the last real code. In this case we send two empty static blocks instead
2664 * of one. (There are no problems if the previous block is stored or fixed.)
2665 * To simplify the code, we assume the worst case of last real code encoded
2669 _tr_align(deflate_state
*s
)
2671 send_bits(s
, STATIC_TREES
<<1, 3);
2672 send_code(s
, END_BLOCK
, static_ltree
);
2673 s
->compressed_len
+= 10L; /* 3 for block type, 7 for EOB */
2675 /* Of the 10 bits for the empty block, we have already sent
2676 * (10 - bi_valid) bits. The lookahead for the last real code (before
2677 * the EOB of the previous block) was thus at least one plus the length
2678 * of the EOB plus what we have just sent of the empty static block.
2680 if (1 + s
->last_eob_len
+ 10 - s
->bi_valid
< 9) {
2681 send_bits(s
, STATIC_TREES
<<1, 3);
2682 send_code(s
, END_BLOCK
, static_ltree
);
2683 s
->compressed_len
+= 10L;
2686 s
->last_eob_len
= 7;
2689 /* ===========================================================================
2690 * Determine the best encoding for the current block: dynamic trees, static
2691 * trees or store, and output the encoded block to the zip file. This function
2692 * returns the total compressed length for the file so far.
2695 * buf: input block, or NULL if too old
2696 * stored_len: length of input block
2697 * eof: true if this is the last block for a file
2700 _tr_flush_block(deflate_state
*s
, charf
*buf
, ulg stored_len
, int eof
)
2702 ulg opt_lenb
, static_lenb
; /* opt_len and static_len in bytes */
2703 int max_blindex
= 0; /* index of last bit length code of non zero freq */
2705 /* Build the Huffman trees unless a stored block is forced */
2708 /* Check if the file is ascii or binary */
2709 if (s
->data_type
== Z_UNKNOWN
) set_data_type(s
);
2711 /* Construct the literal and distance trees */
2712 build_tree(s
, (tree_desc
*)(&(s
->l_desc
)));
2713 Tracev((stderr
, "\nlit data: dyn %ld, stat %ld", s
->opt_len
,
2716 build_tree(s
, (tree_desc
*)(&(s
->d_desc
)));
2717 Tracev((stderr
, "\ndist data: dyn %ld, stat %ld", s
->opt_len
,
2719 /* At this point, opt_len and static_len are the total bit lengths of
2720 * the compressed block data, excluding the tree representations.
2723 /* Build the bit length tree for the above two trees, and get the index
2724 * in bl_order of the last bit length code to send.
2726 max_blindex
= build_bl_tree(s
);
2728 /* Determine the best encoding. Compute first the block length in bytes*/
2729 opt_lenb
= (s
->opt_len
+3+7)>>3;
2730 static_lenb
= (s
->static_len
+3+7)>>3;
2732 Tracev((stderr
, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
2733 opt_lenb
, s
->opt_len
, static_lenb
, s
->static_len
, stored_len
,
2736 if (static_lenb
<= opt_lenb
) opt_lenb
= static_lenb
;
2739 Assert(buf
!= NULL
, "lost buf");
2740 opt_lenb
= static_lenb
= stored_len
+ 5; /* force a stored block */
2743 /* If compression failed and this is the first and last block,
2744 * and if the .zip file can be seeked (to rewrite the local header),
2745 * the whole file is transformed into a stored file:
2747 #ifdef STORED_FILE_OK
2748 # ifdef FORCE_STORED_FILE
2749 if (eof
&& s
->compressed_len
== 0L) { /* force stored file */
2751 if (stored_len
<= opt_lenb
&& eof
&& s
->compressed_len
==0L && seekable()) {
2753 /* Since LIT_BUFSIZE <= 2*WSIZE, the input data must be there: */
2754 if (buf
== NULL
) error ("block vanished");
2756 copy_block(s
, buf
, (unsigned)stored_len
, 0); /* without header */
2757 s
->compressed_len
= stored_len
<< 3;
2760 #endif /* STORED_FILE_OK */
2763 if (buf
!= NULL
) { /* force stored block */
2765 if (stored_len
+4 <= opt_lenb
&& buf
!= NULL
) {
2766 /* 4: two words for the lengths */
2768 /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
2769 * Otherwise we can't have processed more than WSIZE input bytes since
2770 * the last block flush, because compression would have been
2771 * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
2772 * transform a block into a stored block.
2774 _tr_stored_block(s
, buf
, stored_len
, eof
);
2777 } else if (static_lenb
>= 0) { /* force static trees */
2779 } else if (static_lenb
== opt_lenb
) {
2781 send_bits(s
, (STATIC_TREES
<<1)+eof
, 3);
2782 compress_block(s
, (ct_data
*)static_ltree
, (ct_data
*)static_dtree
);
2783 s
->compressed_len
+= 3 + s
->static_len
;
2785 send_bits(s
, (DYN_TREES
<<1)+eof
, 3);
2786 send_all_trees(s
, s
->l_desc
.max_code
+1, s
->d_desc
.max_code
+1,
2788 compress_block(s
, (ct_data
*)s
->dyn_ltree
, (ct_data
*)s
->dyn_dtree
);
2789 s
->compressed_len
+= 3 + s
->opt_len
;
2791 Assert (s
->compressed_len
== s
->bits_sent
, "bad compressed size");
2796 s
->compressed_len
+= 7; /* align on byte boundary */
2798 Tracev((stderr
,"\ncomprlen %lu(%lu) ", s
->compressed_len
>>3,
2799 s
->compressed_len
-7*eof
));
2801 return s
->compressed_len
>> 3;
2804 /* ===========================================================================
2805 * Save the match info and tally the frequency counts. Return true if
2806 * the current block must be flushed.
2809 * dist: distance of matched string
2810 * lc: match length-MIN_MATCH or unmatched char (if dist==0)
2813 _tr_tally(deflate_state
*s
, unsigned dist
, unsigned lc
)
2815 s
->d_buf
[s
->last_lit
] = (ush
)dist
;
2816 s
->l_buf
[s
->last_lit
++] = (uch
)lc
;
2818 /* lc is the unmatched char */
2819 s
->dyn_ltree
[lc
].Freq
++;
2822 /* Here, lc is the match length - MIN_MATCH */
2823 dist
--; /* dist = match distance - 1 */
2824 Assert((ush
)dist
< (ush
)MAX_DIST(s
) &&
2825 (ush
)lc
<= (ush
)(MAX_MATCH
-MIN_MATCH
) &&
2826 (ush
)d_code(dist
) < (ush
)D_CODES
, "_tr_tally: bad match");
2828 s
->dyn_ltree
[length_code
[lc
]+LITERALS
+1].Freq
++;
2829 s
->dyn_dtree
[d_code(dist
)].Freq
++;
2832 /* Try to guess if it is profitable to stop the current block here */
2833 if (s
->level
> 2 && (s
->last_lit
& 0xfff) == 0) {
2834 /* Compute an upper bound for the compressed length */
2835 ulg out_length
= (ulg
)s
->last_lit
*8L;
2836 ulg in_length
= (ulg
)((long)s
->strstart
- s
->block_start
);
2838 for (dcode
= 0; dcode
< D_CODES
; dcode
++) {
2839 out_length
+= (ulg
)s
->dyn_dtree
[dcode
].Freq
*
2840 (5L+extra_dbits
[dcode
]);
2843 Tracev((stderr
,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ",
2844 s
->last_lit
, in_length
, out_length
,
2845 100L - out_length
*100L/in_length
));
2846 if (s
->matches
< s
->last_lit
/2 && out_length
< in_length
/2) return 1;
2848 return (s
->last_lit
== s
->lit_bufsize
-1);
2849 /* We avoid equality with lit_bufsize because of wraparound at 64K
2850 * on 16 bit machines and because stored blocks are restricted to
2855 /* ===========================================================================
2856 * Send the block data compressed using the given Huffman trees
2859 * ltree: literal tree
2860 * dtree: distance tree
2863 compress_block(deflate_state
*s
, ct_data
*ltree
, ct_data
*dtree
)
2865 unsigned dist
; /* distance of matched string */
2866 int lc
; /* match length or unmatched char (if dist == 0) */
2867 unsigned lx
= 0; /* running index in l_buf */
2868 unsigned code
; /* the code to send */
2869 int extra
; /* number of extra bits to send */
2871 if (s
->last_lit
!= 0) do {
2872 dist
= s
->d_buf
[lx
];
2873 lc
= s
->l_buf
[lx
++];
2875 send_code(s
, lc
, ltree
); /* send a literal byte */
2876 Tracecv(isgraph(lc
), (stderr
," '%c' ", lc
));
2878 /* Here, lc is the match length - MIN_MATCH */
2879 code
= length_code
[lc
];
2880 send_code(s
, code
+LITERALS
+1, ltree
); /* send the length code */
2881 extra
= extra_lbits
[code
];
2883 lc
-= base_length
[code
];
2884 send_bits(s
, lc
, extra
); /* send the extra length bits */
2886 dist
--; /* dist is now the match distance - 1 */
2887 code
= d_code(dist
);
2888 Assert (code
< D_CODES
, "bad d_code");
2890 send_code(s
, code
, dtree
); /* send the distance code */
2891 extra
= extra_dbits
[code
];
2893 dist
-= base_dist
[code
];
2894 send_bits(s
, dist
, extra
); /* send the extra distance bits */
2896 } /* literal or match pair ? */
2898 /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */
2899 Assert(s
->pending
< s
->lit_bufsize
+ 2*lx
, "pendingBuf overflow");
2901 } while (lx
< s
->last_lit
);
2903 send_code(s
, END_BLOCK
, ltree
);
2904 s
->last_eob_len
= ltree
[END_BLOCK
].Len
;
2907 /* ===========================================================================
2908 * Set the data type to ASCII or BINARY, using a crude approximation:
2909 * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise.
2910 * IN assertion: the fields freq of dyn_ltree are set and the total of all
2911 * frequencies does not exceed 64K (to fit in an int on 16 bit machines).
2914 set_data_type(deflate_state
*s
)
2917 unsigned ascii_freq
= 0;
2918 unsigned bin_freq
= 0;
2919 while (n
< 7) bin_freq
+= s
->dyn_ltree
[n
++].Freq
;
2920 while (n
< 128) ascii_freq
+= s
->dyn_ltree
[n
++].Freq
;
2921 while (n
< LITERALS
) bin_freq
+= s
->dyn_ltree
[n
++].Freq
;
2922 s
->data_type
= (Byte
)(bin_freq
> (ascii_freq
>> 2) ? Z_BINARY
: Z_ASCII
);
2925 /* ===========================================================================
2926 * Reverse the first len bits of a code, using straightforward code (a faster
2927 * method would use a table)
2928 * IN assertion: 1 <= len <= 15
2931 * code: the value to invert
2932 * len: its bit length
2935 bi_reverse(unsigned code
, int len
)
2940 code
>>= 1, res
<<= 1;
2941 } while (--len
> 0);
2945 /* ===========================================================================
2946 * Flush the bit buffer, keeping at most 7 bits in it.
2949 bi_flush(deflate_state
*s
)
2951 if (s
->bi_valid
== 16) {
2952 put_short(s
, s
->bi_buf
);
2955 } else if (s
->bi_valid
>= 8) {
2956 put_byte(s
, (Byte
)s
->bi_buf
);
2962 /* ===========================================================================
2963 * Flush the bit buffer and align the output on a byte boundary
2966 bi_windup(deflate_state
*s
)
2968 if (s
->bi_valid
> 8) {
2969 put_short(s
, s
->bi_buf
);
2970 } else if (s
->bi_valid
> 0) {
2971 put_byte(s
, (Byte
)s
->bi_buf
);
2976 s
->bits_sent
= (s
->bits_sent
+7) & ~7;
2980 /* ===========================================================================
2981 * Copy a stored block, storing first the length and its
2982 * one's complement if requested.
2985 * buf: the input data
2987 * header: true if block header must be written
2990 copy_block(deflate_state
*s
, charf
*buf
, unsigned len
, int header
)
2992 bi_windup(s
); /* align on byte boundary */
2993 s
->last_eob_len
= 8; /* enough lookahead for inflate */
2996 put_short(s
, (ush
)len
);
2997 put_short(s
, (ush
)~len
);
2999 s
->bits_sent
+= 2*16;
3003 s
->bits_sent
+= (ulg
)len
<<3;
3005 /* bundle up the put_byte(s, *buf++) calls */
3006 zmemcpy(&s
->pending_buf
[s
->pending
], buf
, len
);
3012 /* inflate.c -- zlib interface to inflate modules
3013 * Copyright (C) 1995-1996 Mark Adler
3014 * For conditions of distribution and use, see copyright notice in zlib.h
3017 /* #include "zutil.h" */
3019 /* +++ infblock.h */
3020 /* infblock.h -- header to use infblock.c
3021 * Copyright (C) 1995-1996 Mark Adler
3022 * For conditions of distribution and use, see copyright notice in zlib.h
3025 /* WARNING: this file should *not* be used by applications. It is
3026 part of the implementation of the compression library and is
3027 subject to change. Applications should only use zlib.h.
3030 struct inflate_blocks_state
;
3031 typedef struct inflate_blocks_state FAR inflate_blocks_statef
;
3033 extern inflate_blocks_statef
* inflate_blocks_new
OF((
3035 check_func c
, /* check function */
3036 uInt w
)); /* window size */
3038 extern int inflate_blocks
OF((
3039 inflate_blocks_statef
*,
3041 int)); /* initial return code */
3043 extern void inflate_blocks_reset
OF((
3044 inflate_blocks_statef
*,
3046 uLongf
*)); /* check value on output */
3048 extern int inflate_blocks_free
OF((
3049 inflate_blocks_statef
*,
3051 uLongf
*)); /* check value on output */
3053 extern void inflate_set_dictionary
OF((
3054 inflate_blocks_statef
*s
,
3055 const Bytef
*d
, /* dictionary */
3056 uInt n
)); /* dictionary length */
3058 extern int inflate_addhistory
OF((
3059 inflate_blocks_statef
*,
3062 extern int inflate_packet_flush
OF((
3063 inflate_blocks_statef
*));
3064 /* --- infblock.h */
3066 #ifndef NO_DUMMY_DECL
3067 struct inflate_blocks_state
{int dummy
;}; /* for buggy compilers */
3070 /* inflate private state */
3071 struct internal_state
{
3075 METHOD
, /* waiting for method byte */
3076 FLAG
, /* waiting for flag byte */
3077 DICT4
, /* four dictionary check bytes to go */
3078 DICT3
, /* three dictionary check bytes to go */
3079 DICT2
, /* two dictionary check bytes to go */
3080 DICT1
, /* one dictionary check byte to go */
3081 DICT0
, /* waiting for inflateSetDictionary */
3082 BLOCKS
, /* decompressing blocks */
3083 CHECK4
, /* four check bytes to go */
3084 CHECK3
, /* three check bytes to go */
3085 CHECK2
, /* two check bytes to go */
3086 CHECK1
, /* one check byte to go */
3087 DONE
, /* finished check, done */
3088 BAD
} /* got an error--stay here */
3089 mode
; /* current inflate mode */
3091 /* mode dependent information */
3093 uInt method
; /* if FLAGS, method byte */
3095 uLong was
; /* computed check value */
3096 uLong need
; /* stream check value */
3097 } check
; /* if CHECK, check values to compare */
3098 uInt marker
; /* if BAD, inflateSync's marker bytes count */
3099 } sub
; /* submode */
3101 /* mode independent information */
3102 int nowrap
; /* flag for no wrapper */
3103 uInt wbits
; /* log2(window size) (8..15, defaults to 15) */
3104 inflate_blocks_statef
3105 *blocks
; /* current inflate_blocks state */
3111 inflateReset(z_streamp z
)
3115 if (z
== Z_NULL
|| z
->state
== Z_NULL
)
3116 return Z_STREAM_ERROR
;
3117 z
->total_in
= z
->total_out
= 0;
3119 z
->state
->mode
= z
->state
->nowrap
? BLOCKS
: METHOD
;
3120 inflate_blocks_reset(z
->state
->blocks
, z
, &c
);
3121 Trace((stderr
, "inflate: reset\n"));
3127 inflateEnd(z_streamp z
)
3131 if (z
== Z_NULL
|| z
->state
== Z_NULL
|| z
->zfree
== Z_NULL
)
3132 return Z_STREAM_ERROR
;
3133 if (z
->state
->blocks
!= Z_NULL
)
3134 inflate_blocks_free(z
->state
->blocks
, z
, &c
);
3137 Trace((stderr
, "inflate: end\n"));
3143 inflateInit2_(z_streamp z
, int w
, const char *version
, int stream_size
)
3145 if (version
== Z_NULL
|| version
[0] != ZLIB_VERSION
[0] ||
3146 stream_size
!= sizeof(z_stream
))
3147 return Z_VERSION_ERROR
;
3149 /* initialize state */
3151 return Z_STREAM_ERROR
;
3154 if (z
->zalloc
== Z_NULL
)
3156 z
->zalloc
= zcalloc
;
3157 z
->opaque
= (voidpf
)0;
3159 if (z
->zfree
== Z_NULL
) z
->zfree
= zcfree
;
3161 if ((z
->state
= (struct internal_state FAR
*)
3162 ZALLOC(z
,1,sizeof(struct internal_state
))) == Z_NULL
)
3164 z
->state
->blocks
= Z_NULL
;
3166 /* handle undocumented nowrap option (no zlib header or check) */
3167 z
->state
->nowrap
= 0;
3171 z
->state
->nowrap
= 1;
3174 /* set window size */
3175 if (w
< 8 || w
> 15)
3178 return Z_STREAM_ERROR
;
3180 z
->state
->wbits
= (uInt
)w
;
3182 /* create inflate_blocks state */
3183 if ((z
->state
->blocks
=
3184 inflate_blocks_new(z
, z
->state
->nowrap
? Z_NULL
: adler32
, (uInt
)1 << w
))
3190 Trace((stderr
, "inflate: allocated\n"));
3199 inflateInit_(z_streamp z
, const char *version
, int stream_size
)
3201 return inflateInit2_(z
, DEF_WBITS
, version
, stream_size
);
3205 #define NEEDBYTE {if(z->avail_in==0)goto empty;r=Z_OK;}
3206 #define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
3209 inflate(z_streamp z
, int f
)
3214 if (z
== Z_NULL
|| z
->state
== Z_NULL
|| z
->next_in
== Z_NULL
|| f
< 0)
3215 return Z_STREAM_ERROR
;
3217 while (1) switch (z
->state
->mode
)
3221 if (((z
->state
->sub
.method
= NEXTBYTE
) & 0xf) != Z_DEFLATED
)
3223 z
->state
->mode
= BAD
;
3224 z
->msg
= (char*)"unknown compression method";
3225 z
->state
->sub
.marker
= 5; /* can't try inflateSync */
3228 if ((z
->state
->sub
.method
>> 4) + 8 > z
->state
->wbits
)
3230 z
->state
->mode
= BAD
;
3231 z
->msg
= (char*)"invalid window size";
3232 z
->state
->sub
.marker
= 5; /* can't try inflateSync */
3235 z
->state
->mode
= FLAG
;
3239 if (((z
->state
->sub
.method
<< 8) + b
) % 31)
3241 z
->state
->mode
= BAD
;
3242 z
->msg
= (char*)"incorrect header check";
3243 z
->state
->sub
.marker
= 5; /* can't try inflateSync */
3246 Trace((stderr
, "inflate: zlib header ok\n"));
3247 if (!(b
& PRESET_DICT
))
3249 z
->state
->mode
= BLOCKS
;
3252 z
->state
->mode
= DICT4
;
3255 z
->state
->sub
.check
.need
= (uLong
)NEXTBYTE
<< 24;
3256 z
->state
->mode
= DICT3
;
3259 z
->state
->sub
.check
.need
+= (uLong
)NEXTBYTE
<< 16;
3260 z
->state
->mode
= DICT2
;
3263 z
->state
->sub
.check
.need
+= (uLong
)NEXTBYTE
<< 8;
3264 z
->state
->mode
= DICT1
;
3267 z
->state
->sub
.check
.need
+= (uLong
)NEXTBYTE
;
3268 z
->adler
= z
->state
->sub
.check
.need
;
3269 z
->state
->mode
= DICT0
;
3272 z
->state
->mode
= BAD
;
3273 z
->msg
= (char*)"need dictionary";
3274 z
->state
->sub
.marker
= 0; /* can try inflateSync */
3275 return Z_STREAM_ERROR
;
3277 r
= inflate_blocks(z
->state
->blocks
, z
, r
);
3278 if (f
== Z_PACKET_FLUSH
&& z
->avail_in
== 0 && z
->avail_out
!= 0)
3279 r
= inflate_packet_flush(z
->state
->blocks
);
3280 if (r
== Z_DATA_ERROR
)
3282 z
->state
->mode
= BAD
;
3283 z
->state
->sub
.marker
= 0; /* can try inflateSync */
3286 if (r
!= Z_STREAM_END
)
3289 inflate_blocks_reset(z
->state
->blocks
, z
, &z
->state
->sub
.check
.was
);
3290 if (z
->state
->nowrap
)
3292 z
->state
->mode
= DONE
;
3295 z
->state
->mode
= CHECK4
;
3298 z
->state
->sub
.check
.need
= (uLong
)NEXTBYTE
<< 24;
3299 z
->state
->mode
= CHECK3
;
3302 z
->state
->sub
.check
.need
+= (uLong
)NEXTBYTE
<< 16;
3303 z
->state
->mode
= CHECK2
;
3306 z
->state
->sub
.check
.need
+= (uLong
)NEXTBYTE
<< 8;
3307 z
->state
->mode
= CHECK1
;
3310 z
->state
->sub
.check
.need
+= (uLong
)NEXTBYTE
;
3312 if (z
->state
->sub
.check
.was
!= z
->state
->sub
.check
.need
)
3314 z
->state
->mode
= BAD
;
3315 z
->msg
= (char*)"incorrect data check";
3316 z
->state
->sub
.marker
= 5; /* can't try inflateSync */
3319 Trace((stderr
, "inflate: zlib check ok\n"));
3320 z
->state
->mode
= DONE
;
3322 return Z_STREAM_END
;
3324 return Z_DATA_ERROR
;
3326 return Z_STREAM_ERROR
;
3330 if (f
!= Z_PACKET_FLUSH
)
3332 z
->state
->mode
= BAD
;
3333 z
->msg
= (char *)"need more for packet flush";
3334 z
->state
->sub
.marker
= 0; /* can try inflateSync */
3335 return Z_DATA_ERROR
;
3340 inflateSetDictionary(z_streamp z
, const Bytef
*dictionary
, uInt dictLength
)
3342 uInt length
= dictLength
;
3344 if (z
== Z_NULL
|| z
->state
== Z_NULL
|| z
->state
->mode
!= DICT0
)
3345 return Z_STREAM_ERROR
;
3347 if (adler32(1L, dictionary
, dictLength
) != z
->adler
) return Z_DATA_ERROR
;
3350 if (length
>= ((uInt
)1<<z
->state
->wbits
))
3352 length
= (1<<z
->state
->wbits
)-1;
3353 dictionary
+= dictLength
- length
;
3355 inflate_set_dictionary(z
->state
->blocks
, dictionary
, length
);
3356 z
->state
->mode
= BLOCKS
;
3361 * This subroutine adds the data at next_in/avail_in to the output history
3362 * without performing any output. The output buffer must be "caught up";
3363 * i.e. no pending output (hence s->read equals s->write), and the state must
3364 * be BLOCKS (i.e. we should be willing to see the start of a series of
3365 * BLOCKS). On exit, the output will also be caught up, and the checksum
3366 * will have been updated if need be.
3370 inflateIncomp(z_stream
*z
)
3372 if (z
->state
->mode
!= BLOCKS
)
3373 return Z_DATA_ERROR
;
3374 return inflate_addhistory(z
->state
->blocks
, z
);
3379 inflateSync(z_streamp z
)
3381 uInt n
; /* number of bytes to look at */
3382 Bytef
*p
; /* pointer to bytes */
3383 uInt m
; /* number of marker bytes found in a row */
3384 uLong r
, w
; /* temporaries to save total_in and total_out */
3387 if (z
== Z_NULL
|| z
->state
== Z_NULL
)
3388 return Z_STREAM_ERROR
;
3389 if (z
->state
->mode
!= BAD
)
3391 z
->state
->mode
= BAD
;
3392 z
->state
->sub
.marker
= 0;
3394 if ((n
= z
->avail_in
) == 0)
3397 m
= z
->state
->sub
.marker
;
3402 if (*p
== (Byte
)(m
< 2 ? 0 : 0xff))
3412 z
->total_in
+= p
- z
->next_in
;
3415 z
->state
->sub
.marker
= m
;
3417 /* return no joy or set up to restart on a new block */
3419 return Z_DATA_ERROR
;
3420 r
= z
->total_in
; w
= z
->total_out
;
3422 z
->total_in
= r
; z
->total_out
= w
;
3423 z
->state
->mode
= BLOCKS
;
3431 /* +++ infblock.c */
3432 /* infblock.c -- interpret and process block types to last block
3433 * Copyright (C) 1995-1996 Mark Adler
3434 * For conditions of distribution and use, see copyright notice in zlib.h
3437 /* #include "zutil.h" */
3438 /* #include "infblock.h" */
3440 /* +++ inftrees.h */
3441 /* inftrees.h -- header to use inftrees.c
3442 * Copyright (C) 1995-1996 Mark Adler
3443 * For conditions of distribution and use, see copyright notice in zlib.h
3446 /* WARNING: this file should *not* be used by applications. It is
3447 part of the implementation of the compression library and is
3448 subject to change. Applications should only use zlib.h.
3451 /* Huffman code lookup table entry--this entry is four bytes for machines
3452 that have 16-bit pointers (e.g. PC's in the small or medium model). */
3454 typedef struct inflate_huft_s FAR inflate_huft
;
3456 struct inflate_huft_s
{
3459 Byte Exop
; /* number of extra bits or operation */
3460 Byte Bits
; /* number of bits in this code or subcode */
3462 Bytef
*pad
; /* pad structure to a power of 2 (4 bytes for */
3463 } word
; /* 16-bit, 8 bytes for 32-bit machines) */
3465 uInt Base
; /* literal, length base, or distance base */
3466 inflate_huft
*Next
; /* pointer to next level of table */
3471 extern uInt inflate_hufts
;
3474 extern int inflate_trees_bits
OF((
3475 uIntf
*, /* 19 code lengths */
3476 uIntf
*, /* bits tree desired/actual depth */
3477 inflate_huft
* FAR
*, /* bits tree result */
3478 z_streamp
)); /* for zalloc, zfree functions */
3480 extern int inflate_trees_dynamic
OF((
3481 uInt
, /* number of literal/length codes */
3482 uInt
, /* number of distance codes */
3483 uIntf
*, /* that many (total) code lengths */
3484 uIntf
*, /* literal desired/actual bit depth */
3485 uIntf
*, /* distance desired/actual bit depth */
3486 inflate_huft
* FAR
*, /* literal/length tree result */
3487 inflate_huft
* FAR
*, /* distance tree result */
3488 z_streamp
)); /* for zalloc, zfree functions */
3490 extern int inflate_trees_fixed
OF((
3491 uIntf
*, /* literal desired/actual bit depth */
3492 uIntf
*, /* distance desired/actual bit depth */
3493 inflate_huft
* FAR
*, /* literal/length tree result */
3494 inflate_huft
* FAR
*)); /* distance tree result */
3496 extern int inflate_trees_free
OF((
3497 inflate_huft
*, /* tables to free */
3498 z_streamp
)); /* for zfree function */
3500 /* --- inftrees.h */
3502 /* +++ infcodes.h */
3503 /* infcodes.h -- header to use infcodes.c
3504 * Copyright (C) 1995-1996 Mark Adler
3505 * For conditions of distribution and use, see copyright notice in zlib.h
3508 /* WARNING: this file should *not* be used by applications. It is
3509 part of the implementation of the compression library and is
3510 subject to change. Applications should only use zlib.h.
3513 struct inflate_codes_state
;
3514 typedef struct inflate_codes_state FAR inflate_codes_statef
;
3516 extern inflate_codes_statef
*inflate_codes_new
OF((
3518 inflate_huft
*, inflate_huft
*,
3521 extern int inflate_codes
OF((
3522 inflate_blocks_statef
*,
3526 extern void inflate_codes_free
OF((
3527 inflate_codes_statef
*,
3530 /* --- infcodes.h */
3533 /* infutil.h -- types and macros common to blocks and codes
3534 * Copyright (C) 1995-1996 Mark Adler
3535 * For conditions of distribution and use, see copyright notice in zlib.h
3538 /* WARNING: this file should *not* be used by applications. It is
3539 part of the implementation of the compression library and is
3540 subject to change. Applications should only use zlib.h.
3547 TYPE
, /* get type bits (3, including end bit) */
3548 LENS
, /* get lengths for stored */
3549 STORED
, /* processing stored block */
3550 TABLE
, /* get table lengths */
3551 BTREE
, /* get bit lengths tree for a dynamic block */
3552 DTREE
, /* get length, distance trees for a dynamic block */
3553 CODES
, /* processing fixed or dynamic block */
3554 DRY
, /* output remaining window bytes */
3555 DONEB
, /* finished last block, done */
3556 BADB
} /* got a data error--stuck here */
3559 /* inflate blocks semi-private state */
3560 struct inflate_blocks_state
{
3563 inflate_block_mode mode
; /* current inflate_block mode */
3565 /* mode dependent information */
3567 uInt left
; /* if STORED, bytes left to copy */
3569 uInt table
; /* table lengths (14 bits) */
3570 uInt index
; /* index into blens (or border) */
3571 uIntf
*blens
; /* bit lengths of codes */
3572 uInt bb
; /* bit length tree depth */
3573 inflate_huft
*tb
; /* bit length decoding tree */
3574 } trees
; /* if DTREE, decoding info for trees */
3577 inflate_huft
*td
; /* trees to free */
3578 inflate_codes_statef
3580 } decode
; /* if CODES, current state */
3581 } sub
; /* submode */
3582 uInt last
; /* true if this block is the last block */
3584 /* mode independent information */
3585 uInt bitk
; /* bits in bit buffer */
3586 uLong bitb
; /* bit buffer */
3587 Bytef
*window
; /* sliding window */
3588 Bytef
*end
; /* one byte after sliding window */
3589 Bytef
*read
; /* window read pointer */
3590 Bytef
*write
; /* window write pointer */
3591 check_func checkfn
; /* check function */
3592 uLong check
; /* check on output */
3597 /* defines for inflate input/output */
3598 /* update pointers and return */
3599 #define UPDBITS {s->bitb=b;s->bitk=k;}
3600 #define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
3601 #define UPDOUT {s->write=q;}
3602 #define UPDATE {UPDBITS UPDIN UPDOUT}
3603 #define LEAVE {UPDATE return inflate_flush(s,z,r);}
3604 /* get bytes and bits */
3605 #define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
3606 #define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
3607 #define NEXTBYTE (n--,*p++)
3608 #define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
3609 #define DUMPBITS(j) {b>>=(j);k-=(j);}
3611 #define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q)
3612 #define LOADOUT {q=s->write;m=(uInt)WAVAIL;}
3613 #define WWRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}}
3614 #define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
3615 #define NEEDOUT {if(m==0){WWRAP if(m==0){FLUSH WWRAP if(m==0) LEAVE}}r=Z_OK;}
3616 #define OUTBYTE(a) {*q++=(Byte)(a);m--;}
3617 /* load local pointers */
3618 #define LOAD {LOADIN LOADOUT}
3620 /* masks for lower bits (size given to avoid silly warnings with Visual C++) */
3621 extern uInt inflate_mask
[17];
3623 /* copy as much as possible from the sliding window to the output area */
3624 extern int inflate_flush
OF((
3625 inflate_blocks_statef
*,
3629 #ifndef NO_DUMMY_DECL
3630 struct internal_state
{int dummy
;}; /* for buggy compilers */
3636 #ifndef NO_DUMMY_DECL
3637 struct inflate_codes_state
{int dummy
;}; /* for buggy compilers */
3640 /* Table for deflate from PKZIP's appnote.txt. */
3641 local
const uInt border
[] = { /* Order of the bit length code lengths */
3642 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
3645 Notes beyond the 1.93a appnote.txt:
3647 1. Distance pointers never point before the beginning of the output
3649 2. Distance pointers can point back across blocks, up to 32k away.
3650 3. There is an implied maximum of 7 bits for the bit length table and
3651 15 bits for the actual data.
3652 4. If only one code exists, then it is encoded using one bit. (Zero
3653 would be more efficient, but perhaps a little confusing.) If two
3654 codes exist, they are coded using one bit each (0 and 1).
3655 5. There is no way of sending zero distance codes--a dummy must be
3656 sent if there are none. (History: a pre 2.0 version of PKZIP would
3657 store blocks with no distance codes, but this was discovered to be
3658 too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
3659 zero distance codes, which is sent as one code of zero bits in
3661 6. There are up to 286 literal/length codes. Code 256 represents the
3662 end-of-block. Note however that the static length tree defines
3663 288 codes just to fill out the Huffman codes. Codes 286 and 287
3664 cannot be used though, since there is no length base or extra bits
3665 defined for them. Similarily, there are up to 30 distance codes.
3666 However, static trees define 32 codes (all 5 bits) to fill out the
3667 Huffman codes, but the last two had better not show up in the data.
3668 7. Unzip can check dynamic Huffman blocks for complete code sets.
3669 The exception is that a single code would not be complete (see #4).
3670 8. The five bits following the block type is really the number of
3671 literal codes sent minus 257.
3672 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
3673 (1+6+6). Therefore, to output three times the length, you output
3674 three codes (1+1+1), whereas to output four times the same length,
3675 you only need two codes (1+3). Hmm.
3676 10. In the tree reconstruction algorithm, Code = Code + Increment
3677 only if BitLength(i) is not zero. (Pretty obvious.)
3678 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
3679 12. Note: length code 284 can represent 227-258, but length code 285
3680 really is 258. The last length deserves its own, short code
3681 since it gets used a lot in very redundant files. The length
3682 258 is special since 258 - 3 (the min match length) is 255.
3683 13. The literal/length and distance code bit lengths are read as a
3684 single stream of lengths. It is possible (and advantageous) for
3685 a repeat code (16, 17, or 18) to go across the boundary between
3686 the two sets of lengths.
3691 inflate_blocks_reset(inflate_blocks_statef
*s
, z_streamp z
, uLongf
*c
)
3693 if (s
->checkfn
!= Z_NULL
)
3695 if (s
->mode
== BTREE
|| s
->mode
== DTREE
)
3696 ZFREE(z
, s
->sub
.trees
.blens
);
3697 if (s
->mode
== CODES
)
3699 inflate_codes_free(s
->sub
.decode
.codes
, z
);
3700 inflate_trees_free(s
->sub
.decode
.td
, z
);
3701 inflate_trees_free(s
->sub
.decode
.tl
, z
);
3706 s
->read
= s
->write
= s
->window
;
3707 if (s
->checkfn
!= Z_NULL
)
3708 z
->adler
= s
->check
= (*s
->checkfn
)(0L, Z_NULL
, 0);
3709 Trace((stderr
, "inflate: blocks reset\n"));
3713 inflate_blocks_statef
*
3714 inflate_blocks_new(z_streamp z
, check_func c
, uInt w
)
3716 inflate_blocks_statef
*s
;
3718 if ((s
= (inflate_blocks_statef
*)ZALLOC
3719 (z
,1,sizeof(struct inflate_blocks_state
))) == Z_NULL
)
3721 if ((s
->window
= (Bytef
*)ZALLOC(z
, 1, w
)) == Z_NULL
)
3726 s
->end
= s
->window
+ w
;
3729 Trace((stderr
, "inflate: blocks allocated\n"));
3730 inflate_blocks_reset(s
, z
, &s
->check
);
3736 extern uInt inflate_hufts
;
3740 inflate_blocks(inflate_blocks_statef
*s
, z_streamp z
, int r
)
3742 uInt t
; /* temporary storage */
3743 uLong b
; /* bit buffer */
3744 uInt k
; /* bits in bit buffer */
3745 Bytef
*p
; /* input data pointer */
3746 uInt n
; /* bytes available there */
3747 Bytef
*q
; /* output window write pointer */
3748 uInt m
; /* bytes to end of window or read pointer */
3750 /* copy input/output information to locals (UPDATE macro restores) */
3753 /* process input based on current state */
3754 while (1) switch (s
->mode
)
3762 case 0: /* stored */
3763 Trace((stderr
, "inflate: stored block%s\n",
3764 s
->last
? " (last)" : ""));
3766 t
= k
& 7; /* go to byte boundary */
3768 s
->mode
= LENS
; /* get length of stored block */
3771 Trace((stderr
, "inflate: fixed codes block%s\n",
3772 s
->last
? " (last)" : ""));
3775 inflate_huft
*tl
, *td
;
3777 inflate_trees_fixed(&bl
, &bd
, &tl
, &td
);
3778 s
->sub
.decode
.codes
= inflate_codes_new(bl
, bd
, tl
, td
, z
);
3779 if (s
->sub
.decode
.codes
== Z_NULL
)
3784 s
->sub
.decode
.tl
= Z_NULL
; /* don't try to free these */
3785 s
->sub
.decode
.td
= Z_NULL
;
3790 case 2: /* dynamic */
3791 Trace((stderr
, "inflate: dynamic codes block%s\n",
3792 s
->last
? " (last)" : ""));
3796 case 3: /* illegal */
3799 z
->msg
= (char*)"invalid block type";
3806 if ((((~b
) >> 16) & 0xffff) != (b
& 0xffff))
3809 z
->msg
= (char*)"invalid stored block lengths";
3813 s
->sub
.left
= (uInt
)b
& 0xffff;
3814 b
= k
= 0; /* dump bits */
3815 Tracev((stderr
, "inflate: stored length %u\n", s
->sub
.left
));
3816 s
->mode
= s
->sub
.left
? STORED
: (s
->last
? DRY
: TYPE
);
3828 if ((s
->sub
.left
-= t
) != 0)
3830 Tracev((stderr
, "inflate: stored end, %lu total out\n",
3831 z
->total_out
+ (q
>= s
->read
? q
- s
->read
:
3832 (s
->end
- s
->read
) + (q
- s
->window
))));
3833 s
->mode
= s
->last
? DRY
: TYPE
;
3837 s
->sub
.trees
.table
= t
= (uInt
)b
& 0x3fff;
3838 #ifndef PKZIP_BUG_WORKAROUND
3839 if ((t
& 0x1f) > 29 || ((t
>> 5) & 0x1f) > 29)
3842 z
->msg
= (char*)"too many length or distance symbols";
3847 t
= 258 + (t
& 0x1f) + ((t
>> 5) & 0x1f);
3850 if ((s
->sub
.trees
.blens
= (uIntf
*)ZALLOC(z
, t
, sizeof(uInt
))) == Z_NULL
)
3856 s
->sub
.trees
.index
= 0;
3857 Tracev((stderr
, "inflate: table sizes ok\n"));
3860 while (s
->sub
.trees
.index
< 4 + (s
->sub
.trees
.table
>> 10))
3863 s
->sub
.trees
.blens
[border
[s
->sub
.trees
.index
++]] = (uInt
)b
& 7;
3866 while (s
->sub
.trees
.index
< 19)
3867 s
->sub
.trees
.blens
[border
[s
->sub
.trees
.index
++]] = 0;
3868 s
->sub
.trees
.bb
= 7;
3869 t
= inflate_trees_bits(s
->sub
.trees
.blens
, &s
->sub
.trees
.bb
,
3870 &s
->sub
.trees
.tb
, z
);
3874 if (r
== Z_DATA_ERROR
) {
3875 ZFREE(z
, s
->sub
.trees
.blens
);
3880 s
->sub
.trees
.index
= 0;
3881 Tracev((stderr
, "inflate: bits tree ok\n"));
3884 while (t
= s
->sub
.trees
.table
,
3885 s
->sub
.trees
.index
< 258 + (t
& 0x1f) + ((t
>> 5) & 0x1f))
3890 t
= s
->sub
.trees
.bb
;
3892 h
= s
->sub
.trees
.tb
+ ((uInt
)b
& inflate_mask
[t
]);
3893 t
= h
->word
.what
.Bits
;
3898 s
->sub
.trees
.blens
[s
->sub
.trees
.index
++] = c
;
3900 else /* c == 16..18 */
3902 i
= c
== 18 ? 7 : c
- 14;
3903 j
= c
== 18 ? 11 : 3;
3906 j
+= (uInt
)b
& inflate_mask
[i
];
3908 i
= s
->sub
.trees
.index
;
3909 t
= s
->sub
.trees
.table
;
3910 if (i
+ j
> 258 + (t
& 0x1f) + ((t
>> 5) & 0x1f) ||
3913 inflate_trees_free(s
->sub
.trees
.tb
, z
);
3914 ZFREE(z
, s
->sub
.trees
.blens
);
3916 z
->msg
= (char*)"invalid bit length repeat";
3920 c
= c
== 16 ? s
->sub
.trees
.blens
[i
- 1] : 0;
3922 s
->sub
.trees
.blens
[i
++] = c
;
3924 s
->sub
.trees
.index
= i
;
3927 inflate_trees_free(s
->sub
.trees
.tb
, z
);
3928 s
->sub
.trees
.tb
= Z_NULL
;
3931 inflate_huft
*tl
, *td
;
3932 inflate_codes_statef
*c
;
3934 bl
= 9; /* must be <= 9 for lookahead assumptions */
3935 bd
= 6; /* must be <= 9 for lookahead assumptions */
3936 t
= s
->sub
.trees
.table
;
3940 t
= inflate_trees_dynamic(257 + (t
& 0x1f), 1 + ((t
>> 5) & 0x1f),
3941 s
->sub
.trees
.blens
, &bl
, &bd
, &tl
, &td
, z
);
3944 if (t
== (uInt
)Z_DATA_ERROR
) {
3945 ZFREE(z
, s
->sub
.trees
.blens
);
3951 Tracev((stderr
, "inflate: trees ok, %d * %d bytes used\n",
3952 inflate_hufts
, sizeof(inflate_huft
)));
3953 if ((c
= inflate_codes_new(bl
, bd
, tl
, td
, z
)) == Z_NULL
)
3955 inflate_trees_free(td
, z
);
3956 inflate_trees_free(tl
, z
);
3961 * this ZFREE must occur *BEFORE* we mess with sub.decode, because
3962 * sub.trees is union'd with sub.decode.
3964 ZFREE(z
, s
->sub
.trees
.blens
);
3965 s
->sub
.decode
.codes
= c
;
3966 s
->sub
.decode
.tl
= tl
;
3967 s
->sub
.decode
.td
= td
;
3972 if ((r
= inflate_codes(s
, z
, r
)) != Z_STREAM_END
)
3973 return inflate_flush(s
, z
, r
);
3975 inflate_codes_free(s
->sub
.decode
.codes
, z
);
3976 inflate_trees_free(s
->sub
.decode
.td
, z
);
3977 inflate_trees_free(s
->sub
.decode
.tl
, z
);
3979 Tracev((stderr
, "inflate: codes end, %lu total out\n",
3980 z
->total_out
+ (q
>= s
->read
? q
- s
->read
:
3981 (s
->end
- s
->read
) + (q
- s
->window
))));
3987 if (k
> 7) /* return unused byte, if any */
3989 Assert(k
< 16, "inflate_codes grabbed too many bytes")
3992 p
--; /* can always return one */
3997 if (s
->read
!= s
->write
)
4014 inflate_blocks_free(inflate_blocks_statef
*s
, z_streamp z
, uLongf
*c
)
4016 inflate_blocks_reset(s
, z
, c
);
4017 ZFREE(z
, s
->window
);
4019 Trace((stderr
, "inflate: blocks freed\n"));
4025 inflate_set_dictionary(inflate_blocks_statef
*s
, const Bytef
*d
, uInt n
)
4027 zmemcpy((charf
*)s
->window
, d
, n
);
4028 s
->read
= s
->write
= s
->window
+ n
;
4032 * This subroutine adds the data at next_in/avail_in to the output history
4033 * without performing any output. The output buffer must be "caught up";
4034 * i.e. no pending output (hence s->read equals s->write), and the state must
4035 * be BLOCKS (i.e. we should be willing to see the start of a series of
4036 * BLOCKS). On exit, the output will also be caught up, and the checksum
4037 * will have been updated if need be.
4040 inflate_addhistory(inflate_blocks_statef
*s
, z_stream
*z
)
4042 uLong b
; /* bit buffer */ /* NOT USED HERE */
4043 uInt k
; /* bits in bit buffer */ /* NOT USED HERE */
4044 uInt t
; /* temporary storage */
4045 Bytef
*p
; /* input data pointer */
4046 uInt n
; /* bytes available there */
4047 Bytef
*q
; /* output window write pointer */
4048 uInt m
; /* bytes to end of window or read pointer */
4050 if (s
->read
!= s
->write
)
4051 return Z_STREAM_ERROR
;
4052 if (s
->mode
!= TYPE
)
4053 return Z_DATA_ERROR
;
4055 /* we're ready to rock */
4057 /* while there is input ready, copy to output buffer, moving
4058 * pointers as needed.
4061 t
= n
; /* how many to do */
4062 /* is there room until end of buffer? */
4064 /* update check information */
4065 if (s
->checkfn
!= Z_NULL
)
4066 s
->check
= (*s
->checkfn
)(s
->check
, q
, t
);
4072 s
->read
= q
; /* drag read pointer forward */
4073 /* WWRAP */ /* expand WWRAP macro by hand to handle s->read */
4075 s
->read
= q
= s
->window
;
4085 * At the end of a Deflate-compressed PPP packet, we expect to have seen
4086 * a `stored' block type value but not the (zero) length bytes.
4089 inflate_packet_flush(inflate_blocks_statef
*s
)
4091 if (s
->mode
!= LENS
)
4092 return Z_DATA_ERROR
;
4096 /* --- infblock.c */
4098 /* +++ inftrees.c */
4099 /* inftrees.c -- generate Huffman trees for efficient decoding
4100 * Copyright (C) 1995-1996 Mark Adler
4101 * For conditions of distribution and use, see copyright notice in zlib.h
4104 /* #include "zutil.h" */
4105 /* #include "inftrees.h" */
4107 char inflate_copyright
[] = " inflate 1.0.4 Copyright 1995-1996 Mark Adler ";
4109 If you use the zlib library in a product, an acknowledgment is welcome
4110 in the documentation of your product. If for some reason you cannot
4111 include such an acknowledgment, I would appreciate that you keep this
4112 copyright string in the executable of your product.
4115 #ifndef NO_DUMMY_DECL
4116 struct internal_state
{int dummy
;}; /* for buggy compilers */
4119 /* simplify the use of the inflate_huft type with some defines */
4120 #define base more.Base
4121 #define next more.Next
4122 #define exop word.what.Exop
4123 #define bits word.what.Bits
4126 local
int huft_build
OF((
4127 uIntf
*, /* code lengths in bits */
4128 uInt
, /* number of codes */
4129 uInt
, /* number of "simple" codes */
4130 const uIntf
*, /* list of base values for non-simple codes */
4131 const uIntf
*, /* list of extra bits for non-simple codes */
4132 inflate_huft
* FAR
*,/* result: starting table */
4133 uIntf
*, /* maximum lookup bits (returns actual) */
4134 z_streamp
)); /* for zalloc function */
4136 local voidpf zfalloc
OF((
4137 voidpf
, /* opaque pointer (not used) */
4138 uInt
, /* number of items */
4139 uInt
)); /* size of item */
4141 /* Tables for deflate from PKZIP's appnote.txt. */
4142 local
const uInt cplens
[31] = { /* Copy lengths for literal codes 257..285 */
4143 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
4144 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
4145 /* see note #13 above about 258 */
4146 local
const uInt cplext
[31] = { /* Extra bits for literal codes 257..285 */
4147 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
4148 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 112, 112}; /* 112==invalid */
4149 local
const uInt cpdist
[30] = { /* Copy offsets for distance codes 0..29 */
4150 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
4151 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
4152 8193, 12289, 16385, 24577};
4153 local
const uInt cpdext
[30] = { /* Extra bits for distance codes */
4154 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
4155 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
4159 Huffman code decoding is performed using a multi-level table lookup.
4160 The fastest way to decode is to simply build a lookup table whose
4161 size is determined by the longest code. However, the time it takes
4162 to build this table can also be a factor if the data being decoded
4163 is not very long. The most common codes are necessarily the
4164 shortest codes, so those codes dominate the decoding time, and hence
4165 the speed. The idea is you can have a shorter table that decodes the
4166 shorter, more probable codes, and then point to subsidiary tables for
4167 the longer codes. The time it costs to decode the longer codes is
4168 then traded against the time it takes to make longer tables.
4170 This results of this trade are in the variables lbits and dbits
4171 below. lbits is the number of bits the first level table for literal/
4172 length codes can decode in one step, and dbits is the same thing for
4173 the distance codes. Subsequent tables are also less than or equal to
4174 those sizes. These values may be adjusted either when all of the
4175 codes are shorter than that, in which case the longest code length in
4176 bits is used, or when the shortest code is *longer* than the requested
4177 table size, in which case the length of the shortest code in bits is
4180 There are two different values for the two tables, since they code a
4181 different number of possibilities each. The literal/length table
4182 codes 286 possible values, or in a flat code, a little over eight
4183 bits. The distance table codes 30 possible values, or a little less
4184 than five bits, flat. The optimum values for speed end up being
4185 about one bit more than those, so lbits is 8+1 and dbits is 5+1.
4186 The optimum values may differ though from machine to machine, and
4187 possibly even between compilers. Your mileage may vary.
4191 /* If BMAX needs to be larger than 16, then h and x[] should be uLong. */
4192 #define BMAX 15 /* maximum bit length of any code */
4193 #define N_MAX 288 /* maximum number of codes in any set */
4201 * b: code lengths in bits (all assumed <= BMAX)
4202 * n: number of codes (assumed <= N_MAX)
4203 * s: number of simple-valued codes (0..s-1)
4204 * d: list of base values for non-simple codes
4205 * e: list of extra bits for non-simple codes
4206 * t: result: starting table
4207 * m: maximum lookup bits, returns actual
4208 * zs: for zalloc function
4210 * Given a list of code lengths and a maximum table size, make a set of
4211 * tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR
4212 * if the given code set is incomplete (the tables are still built in this
4213 * case), Z_DATA_ERROR if the input is invalid (an over-subscribed set of
4214 * lengths), or Z_MEM_ERROR if not enough memory.
4217 huft_build(uIntf
*b
, uInt n
, uInt s
, const uIntf
*d
, const uIntf
*e
,
4218 inflate_huft
* FAR
*t
, uIntf
*m
, z_streamp zs
)
4221 uInt a
; /* counter for codes of length k */
4222 uInt c
[BMAX
+1]; /* bit length count table */
4223 uInt f
; /* i repeats in table every f entries */
4224 int g
; /* maximum code length */
4225 int h
; /* table level */
4226 uInt i
; /* counter, current code */
4227 uInt j
; /* counter */
4228 int k
; /* number of bits in current code */
4229 int l
; /* bits per table (returned in m) */
4230 uIntf
*p
; /* pointer into c[], b[], or v[] */
4231 inflate_huft
*q
; /* points to current table */
4232 struct inflate_huft_s r
; /* table entry for structure assignment */
4233 inflate_huft
*u
[BMAX
]; /* table stack */
4234 uInt v
[N_MAX
]; /* values in order of bit length */
4235 int w
; /* bits before this table == (l * h) */
4236 uInt x
[BMAX
+1]; /* bit offsets, then code stack */
4237 uIntf
*xp
; /* pointer into x */
4238 int y
; /* number of dummy codes added */
4239 uInt z
; /* number of entries in current table */
4242 /* Generate counts for each bit length */
4244 #define C0 *p++ = 0;
4245 #define C2 C0 C0 C0 C0
4246 #define C4 C2 C2 C2 C2
4247 C4
/* clear c[]--assume BMAX+1 is 16 */
4250 c
[*p
++]++; /* assume all entries <= BMAX */
4252 if (c
[0] == n
) /* null input--all zero length codes */
4254 *t
= (inflate_huft
*)Z_NULL
;
4260 /* Find minimum and maximum length, bound *m by those */
4262 for (j
= 1; j
<= BMAX
; j
++)
4265 k
= j
; /* minimum code length */
4268 for (i
= BMAX
; i
; i
--)
4271 g
= i
; /* maximum code length */
4277 /* Adjust last length count to fill out codes, if needed */
4278 for (y
= 1 << j
; j
< i
; j
++, y
<<= 1)
4279 if ((y
-= c
[j
]) < 0)
4280 return Z_DATA_ERROR
;
4281 if ((y
-= c
[i
]) < 0)
4282 return Z_DATA_ERROR
;
4286 /* Generate starting offsets into the value table for each length */
4288 p
= c
+ 1; xp
= x
+ 2;
4289 while (--i
) { /* note that i == g from above */
4290 *xp
++ = (j
+= *p
++);
4294 /* Make a table of values in order of bit lengths */
4297 if ((j
= *p
++) != 0)
4300 n
= x
[g
]; /* set n to length of v */
4303 /* Generate the Huffman codes and for each, make the table entries */
4304 x
[0] = i
= 0; /* first Huffman code is zero */
4305 p
= v
; /* grab values in bit order */
4306 h
= -1; /* no tables yet--level -1 */
4307 w
= -l
; /* bits decoded == (l * h) */
4308 u
[0] = (inflate_huft
*)Z_NULL
; /* just to keep compilers happy */
4309 q
= (inflate_huft
*)Z_NULL
; /* ditto */
4312 /* go through the bit lengths (k already is bits in shortest code) */
4318 /* here i is the Huffman code of length k bits for value *p */
4319 /* make tables up to required level */
4323 w
+= l
; /* previous table always l bits */
4325 /* compute minimum size table less than or equal to l bits */
4327 z
= z
> (uInt
)l
? l
: z
; /* table size upper limit */
4328 if ((f
= 1 << (j
= k
- w
)) > a
+ 1) /* try a k-w bit table */
4329 { /* too few codes for k-w bit table */
4330 f
-= a
+ 1; /* deduct codes from patterns left */
4333 while (++j
< z
) /* try smaller tables up to z bits */
4335 if ((f
<<= 1) <= *++xp
)
4336 break; /* enough codes to use up j bits */
4337 f
-= *xp
; /* else deduct codes from patterns */
4340 z
= 1 << j
; /* table entries for j-bit table */
4342 /* allocate and link in new table */
4343 if ((q
= (inflate_huft
*)ZALLOC
4344 (zs
,z
+ 1,sizeof(inflate_huft
))) == Z_NULL
)
4347 inflate_trees_free(u
[0], zs
);
4348 return Z_MEM_ERROR
; /* not enough memory */
4351 inflate_hufts
+= z
+ 1;
4353 *t
= q
+ 1; /* link to list for huft_free() */
4354 *(t
= &(q
->next
)) = Z_NULL
;
4355 u
[h
] = ++q
; /* table starts after link */
4357 /* connect to last table, if there is one */
4360 x
[h
] = i
; /* save pattern for backing up */
4361 r
.bits
= (Byte
)l
; /* bits to dump before this table */
4362 r
.exop
= (Byte
)j
; /* bits in this table */
4363 r
.next
= q
; /* pointer to this table */
4364 j
= i
>> (w
- l
); /* (get around Turbo C bug) */
4365 u
[h
-1][j
] = r
; /* connect to last table */
4369 /* set up table entry in r */
4370 r
.bits
= (Byte
)(k
- w
);
4372 r
.exop
= 128 + 64; /* out of values--invalid code */
4375 r
.exop
= (Byte
)(*p
< 256 ? 0 : 32 + 64); /* 256 is end-of-block */
4376 r
.base
= *p
++; /* simple code is just the value */
4380 r
.exop
= (Byte
)(e
[*p
- s
] + 16 + 64);/* non-simple--look up in lists */
4381 r
.base
= d
[*p
++ - s
];
4384 /* fill code-like entries with r */
4386 for (j
= i
>> w
; j
< z
; j
+= f
)
4389 /* backwards increment the k-bit code i */
4390 for (j
= 1 << (k
- 1); i
& j
; j
>>= 1)
4394 /* backup over finished tables */
4395 while ((i
& ((1 << w
) - 1)) != x
[h
])
4397 h
--; /* don't need to update q */
4404 /* Return Z_BUF_ERROR if we were given an incomplete table */
4405 return y
!= 0 && g
!= 1 ? Z_BUF_ERROR
: Z_OK
;
4410 * c: 19 code lengths
4411 * bb: bits tree desired/actual depth
4412 * tb: bits tree result
4413 * z: for zfree function
4416 inflate_trees_bits(uIntf
*c
, uIntf
*bb
, inflate_huft
* FAR
*tb
, z_streamp z
)
4420 r
= huft_build(c
, 19, 19, (uIntf
*)Z_NULL
, (uIntf
*)Z_NULL
, tb
, bb
, z
);
4421 if (r
== Z_DATA_ERROR
)
4422 z
->msg
= (char*)"oversubscribed dynamic bit lengths tree";
4423 else if (r
== Z_BUF_ERROR
|| *bb
== 0)
4425 inflate_trees_free(*tb
, z
);
4426 z
->msg
= (char*)"incomplete dynamic bit lengths tree";
4434 * nl: number of literal/length codes
4435 * nd: number of distance codes
4436 * c: that many (total) code lengths
4437 * bl: literal desired/actual bit depth
4438 * bd: distance desired/actual bit depth
4439 * tl: literal/length tree result
4440 * td: distance tree result
4441 * z: for zfree function
4444 inflate_trees_dynamic(uInt nl
, uInt nd
, uIntf
*c
, uIntf
*bl
, uIntf
*bd
,
4445 inflate_huft
* FAR
*tl
, inflate_huft
* FAR
*td
,
4450 /* build literal/length tree */
4451 r
= huft_build(c
, nl
, 257, cplens
, cplext
, tl
, bl
, z
);
4452 if (r
!= Z_OK
|| *bl
== 0)
4454 if (r
== Z_DATA_ERROR
)
4455 z
->msg
= (char*)"oversubscribed literal/length tree";
4456 else if (r
!= Z_MEM_ERROR
)
4458 inflate_trees_free(*tl
, z
);
4459 z
->msg
= (char*)"incomplete literal/length tree";
4465 /* build distance tree */
4466 r
= huft_build(c
+ nl
, nd
, 0, cpdist
, cpdext
, td
, bd
, z
);
4467 if (r
!= Z_OK
|| (*bd
== 0 && nl
> 257))
4469 if (r
== Z_DATA_ERROR
)
4470 z
->msg
= (char*)"oversubscribed distance tree";
4471 else if (r
== Z_BUF_ERROR
) {
4472 #ifdef PKZIP_BUG_WORKAROUND
4476 inflate_trees_free(*td
, z
);
4477 z
->msg
= (char*)"incomplete distance tree";
4480 else if (r
!= Z_MEM_ERROR
)
4482 z
->msg
= (char*)"empty distance tree with lengths";
4485 inflate_trees_free(*tl
, z
);
4495 /* build fixed tables only once--keep them here */
4496 local
int fixed_built
= 0;
4497 #define FIXEDH 530 /* number of hufts used by fixed tables */
4498 local inflate_huft fixed_mem
[FIXEDH
];
4499 local uInt fixed_bl
;
4500 local uInt fixed_bd
;
4501 local inflate_huft
*fixed_tl
;
4502 local inflate_huft
*fixed_td
;
4507 * n: number of items
4511 zfalloc(voidpf q
, uInt n
, uInt s
)
4513 Assert(s
== sizeof(inflate_huft
) && n
<= *(intf
*)q
,
4514 "inflate_trees zfalloc overflow");
4515 *(intf
*)q
-= n
+s
-s
; /* s-s to avoid warning */
4516 return (voidpf
)(fixed_mem
+ *(intf
*)q
);
4521 * bl: literal desired/actual bit depth
4522 * bd: distance desired/actual bit depth
4523 * tl: literal/length tree result
4524 * td: distance tree result
4527 inflate_trees_fixed(uIntf
*bl
, uIntf
*bd
, inflate_huft
* FAR
*tl
,
4528 inflate_huft
* FAR
*td
)
4530 /* build fixed tables if not already (multiple overlapped executions ok) */
4533 int k
; /* temporary variable */
4534 unsigned c
[288]; /* length list for huft_build */
4535 z_stream z
; /* for zfalloc function */
4536 int f
= FIXEDH
; /* number of hufts left in fixed_mem */
4538 /* set up fake z_stream for memory routines */
4541 z
.opaque
= (voidpf
)&f
;
4544 for (k
= 0; k
< 144; k
++)
4546 for (; k
< 256; k
++)
4548 for (; k
< 280; k
++)
4550 for (; k
< 288; k
++)
4553 huft_build(c
, 288, 257, cplens
, cplext
, &fixed_tl
, &fixed_bl
, &z
);
4555 /* distance table */
4556 for (k
= 0; k
< 30; k
++)
4559 huft_build(c
, 30, 0, cpdist
, cpdext
, &fixed_td
, &fixed_bd
, &z
);
4562 Assert(f
== 0, "invalid build of fixed tables");
4575 * z: for zfree function
4576 * Free the malloc'ed tables built by huft_build(), which makes a linked
4577 * list of the tables it made, with the links in a dummy first entry of
4581 inflate_trees_free(inflate_huft
*t
, z_streamp z
)
4583 inflate_huft
*p
, *q
, *r
;
4585 /* Reverse linked list */
4595 /* Go through linked list, freeing from the malloced (t[-1]) address. */
4604 /* --- inftrees.c */
4606 /* +++ infcodes.c */
4607 /* infcodes.c -- process literals and length/distance pairs
4608 * Copyright (C) 1995-1996 Mark Adler
4609 * For conditions of distribution and use, see copyright notice in zlib.h
4612 /* #include "zutil.h" */
4613 /* #include "inftrees.h" */
4614 /* #include "infblock.h" */
4615 /* #include "infcodes.h" */
4616 /* #include "infutil.h" */
4619 /* inffast.h -- header to use inffast.c
4620 * Copyright (C) 1995-1996 Mark Adler
4621 * For conditions of distribution and use, see copyright notice in zlib.h
4624 /* WARNING: this file should *not* be used by applications. It is
4625 part of the implementation of the compression library and is
4626 subject to change. Applications should only use zlib.h.
4629 extern int inflate_fast
OF((
4634 inflate_blocks_statef
*,
4638 /* simplify the use of the inflate_huft type with some defines */
4639 #define base more.Base
4640 #define next more.Next
4641 #define exop word.what.Exop
4642 #define bits word.what.Bits
4644 /* inflate codes private state */
4645 struct inflate_codes_state
{
4648 enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
4649 START
, /* x: set up for LEN */
4650 LEN
, /* i: get length/literal/eob next */
4651 LENEXT
, /* i: getting length extra (have base) */
4652 DIST
, /* i: get distance next */
4653 DISTEXT
, /* i: getting distance extra */
4654 COPY
, /* o: copying bytes in window, waiting for space */
4655 LIT
, /* o: got literal, waiting for output space */
4656 WASH
, /* o: got eob, possibly still output waiting */
4657 END
, /* x: got eob and all data flushed */
4658 BADCODE
} /* x: got error */
4659 mode
; /* current inflate_codes mode */
4661 /* mode dependent information */
4665 inflate_huft
*tree
; /* pointer into tree */
4666 uInt need
; /* bits needed */
4667 } code
; /* if LEN or DIST, where in tree */
4668 uInt lit
; /* if LIT, literal */
4670 uInt get
; /* bits to get for extra */
4671 uInt dist
; /* distance back to copy from */
4672 } copy
; /* if EXT or COPY, where and how much */
4673 } sub
; /* submode */
4675 /* mode independent information */
4676 Byte lbits
; /* ltree bits decoded per branch */
4677 Byte dbits
; /* dtree bits decoder per branch */
4678 inflate_huft
*ltree
; /* literal/length/eob tree */
4679 inflate_huft
*dtree
; /* distance tree */
4685 * td: need separate declaration for Borland C++
4687 inflate_codes_statef
*
4688 inflate_codes_new(uInt bl
, uInt bd
, inflate_huft
*tl
, inflate_huft
*td
,
4691 inflate_codes_statef
*c
;
4693 if ((c
= (inflate_codes_statef
*)
4694 ZALLOC(z
,1,sizeof(struct inflate_codes_state
))) != Z_NULL
)
4697 c
->lbits
= (Byte
)bl
;
4698 c
->dbits
= (Byte
)bd
;
4701 Tracev((stderr
, "inflate: codes new\n"));
4708 inflate_codes(inflate_blocks_statef
*s
, z_streamp z
, int r
)
4710 uInt j
; /* temporary storage */
4711 inflate_huft
*t
; /* temporary pointer */
4712 uInt e
; /* extra bits or operation */
4713 uLong b
; /* bit buffer */
4714 uInt k
; /* bits in bit buffer */
4715 Bytef
*p
; /* input data pointer */
4716 uInt n
; /* bytes available there */
4717 Bytef
*q
; /* output window write pointer */
4718 uInt m
; /* bytes to end of window or read pointer */
4719 Bytef
*f
; /* pointer to copy strings from */
4720 inflate_codes_statef
*c
= s
->sub
.decode
.codes
; /* codes state */
4722 /* copy input/output information to locals (UPDATE macro restores) */
4725 /* process input and output based on current state */
4726 while (1) switch (c
->mode
)
4727 { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
4728 case START
: /* x: set up for LEN */
4730 if (m
>= 258 && n
>= 10)
4733 r
= inflate_fast(c
->lbits
, c
->dbits
, c
->ltree
, c
->dtree
, s
, z
);
4737 c
->mode
= r
== Z_STREAM_END
? WASH
: BADCODE
;
4742 c
->sub
.code
.need
= c
->lbits
;
4743 c
->sub
.code
.tree
= c
->ltree
;
4745 case LEN
: /* i: get length/literal/eob next */
4746 j
= c
->sub
.code
.need
;
4748 t
= c
->sub
.code
.tree
+ ((uInt
)b
& inflate_mask
[j
]);
4750 e
= (uInt
)(t
->exop
);
4751 if (e
== 0) /* literal */
4753 c
->sub
.lit
= t
->base
;
4754 Tracevv((stderr
, t
->base
>= 0x20 && t
->base
< 0x7f ?
4755 "inflate: literal '%c'\n" :
4756 "inflate: literal 0x%02x\n", t
->base
));
4760 if (e
& 16) /* length */
4762 c
->sub
.copy
.get
= e
& 15;
4767 if ((e
& 64) == 0) /* next table */
4769 c
->sub
.code
.need
= e
;
4770 c
->sub
.code
.tree
= t
->next
;
4773 if (e
& 32) /* end of block */
4775 Tracevv((stderr
, "inflate: end of block\n"));
4779 c
->mode
= BADCODE
; /* invalid code */
4780 z
->msg
= (char*)"invalid literal/length code";
4783 case LENEXT
: /* i: getting length extra (have base) */
4784 j
= c
->sub
.copy
.get
;
4786 c
->len
+= (uInt
)b
& inflate_mask
[j
];
4788 c
->sub
.code
.need
= c
->dbits
;
4789 c
->sub
.code
.tree
= c
->dtree
;
4790 Tracevv((stderr
, "inflate: length %u\n", c
->len
));
4792 case DIST
: /* i: get distance next */
4793 j
= c
->sub
.code
.need
;
4795 t
= c
->sub
.code
.tree
+ ((uInt
)b
& inflate_mask
[j
]);
4797 e
= (uInt
)(t
->exop
);
4798 if (e
& 16) /* distance */
4800 c
->sub
.copy
.get
= e
& 15;
4801 c
->sub
.copy
.dist
= t
->base
;
4805 if ((e
& 64) == 0) /* next table */
4807 c
->sub
.code
.need
= e
;
4808 c
->sub
.code
.tree
= t
->next
;
4811 c
->mode
= BADCODE
; /* invalid code */
4812 z
->msg
= (char*)"invalid distance code";
4815 case DISTEXT
: /* i: getting distance extra */
4816 j
= c
->sub
.copy
.get
;
4818 c
->sub
.copy
.dist
+= (uInt
)b
& inflate_mask
[j
];
4820 Tracevv((stderr
, "inflate: distance %u\n", c
->sub
.copy
.dist
));
4822 case COPY
: /* o: copying bytes in window, waiting for space */
4823 #ifndef __TURBOC__ /* Turbo C bug for following expression */
4824 f
= (uInt
)(q
- s
->window
) < c
->sub
.copy
.dist
?
4825 s
->end
- (c
->sub
.copy
.dist
- (q
- s
->window
)) :
4826 q
- c
->sub
.copy
.dist
;
4828 f
= q
- c
->sub
.copy
.dist
;
4829 if ((uInt
)(q
- s
->window
) < c
->sub
.copy
.dist
)
4830 f
= s
->end
- (c
->sub
.copy
.dist
- (uInt
)(q
- s
->window
));
4842 case LIT
: /* o: got literal, waiting for output space */
4847 case WASH
: /* o: got eob, possibly more output */
4849 if (s
->read
!= s
->write
)
4855 case BADCODE
: /* x: got error */
4866 inflate_codes_free(inflate_codes_statef
*c
, z_streamp z
)
4869 Tracev((stderr
, "inflate: codes free\n"));
4871 /* --- infcodes.c */
4874 /* inflate_util.c -- data and routines common to blocks and codes
4875 * Copyright (C) 1995-1996 Mark Adler
4876 * For conditions of distribution and use, see copyright notice in zlib.h
4879 /* #include "zutil.h" */
4880 /* #include "infblock.h" */
4881 /* #include "inftrees.h" */
4882 /* #include "infcodes.h" */
4883 /* #include "infutil.h" */
4885 #ifndef NO_DUMMY_DECL
4886 struct inflate_codes_state
{int dummy
;}; /* for buggy compilers */
4889 /* And'ing with mask[n] masks the lower n bits */
4890 uInt inflate_mask
[17] = {
4892 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
4893 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
4897 /* copy as much as possible from the sliding window to the output area */
4899 inflate_flush(inflate_blocks_statef
*s
, z_streamp z
, int r
)
4905 /* local copies of source and destination pointers */
4909 /* compute number of bytes to copy as far as end of window */
4910 n
= (uInt
)((q
<= s
->write
? s
->write
: s
->end
) - q
);
4911 if (n
> z
->avail_out
) n
= z
->avail_out
;
4912 if (n
&& r
== Z_BUF_ERROR
) r
= Z_OK
;
4914 /* update counters */
4918 /* update check information */
4919 if (s
->checkfn
!= Z_NULL
)
4920 z
->adler
= s
->check
= (*s
->checkfn
)(s
->check
, q
, n
);
4922 /* copy as far as end of window */
4929 /* see if more to copy at beginning of window */
4934 if (s
->write
== s
->end
)
4935 s
->write
= s
->window
;
4937 /* compute bytes to copy */
4938 n
= (uInt
)(s
->write
- q
);
4939 if (n
> z
->avail_out
) n
= z
->avail_out
;
4940 if (n
&& r
== Z_BUF_ERROR
) r
= Z_OK
;
4942 /* update counters */
4946 /* update check information */
4947 if (s
->checkfn
!= Z_NULL
)
4948 z
->adler
= s
->check
= (*s
->checkfn
)(s
->check
, q
, n
);
4958 /* update pointers */
4968 /* inffast.c -- process literals and length/distance pairs fast
4969 * Copyright (C) 1995-1996 Mark Adler
4970 * For conditions of distribution and use, see copyright notice in zlib.h
4973 /* #include "zutil.h" */
4974 /* #include "inftrees.h" */
4975 /* #include "infblock.h" */
4976 /* #include "infcodes.h" */
4977 /* #include "infutil.h" */
4978 /* #include "inffast.h" */
4980 #ifndef NO_DUMMY_DECL
4981 struct inflate_codes_state
{int dummy
;}; /* for buggy compilers */
4984 /* simplify the use of the inflate_huft type with some defines */
4985 #define base more.Base
4986 #define next more.Next
4987 #define exop word.what.Exop
4988 #define bits word.what.Bits
4990 /* macros for bit input with no checking and for returning unused bytes */
4991 #define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}}
4992 #define UNGRAB {n+=(c=k>>3);p-=c;k&=7;}
4994 /* Called with number of bytes left to write in window at least 258
4995 * (the maximum string length) and number of input bytes available
4996 * at least ten. The ten bytes are six bytes for the longest length/
4997 * distance pair plus four bytes for overloading the bit buffer.
5000 * td: need separate declaration for Borland C++
5003 inflate_fast(uInt bl
, uInt bd
, inflate_huft
*tl
, inflate_huft
*td
,
5004 inflate_blocks_statef
*s
, z_streamp z
)
5006 inflate_huft
*t
; /* temporary pointer */
5007 uInt e
; /* extra bits or operation */
5008 uLong b
; /* bit buffer */
5009 uInt k
; /* bits in bit buffer */
5010 Bytef
*p
; /* input data pointer */
5011 uInt n
; /* bytes available there */
5012 Bytef
*q
; /* output window write pointer */
5013 uInt m
; /* bytes to end of window or read pointer */
5014 uInt ml
; /* mask for literal/length tree */
5015 uInt md
; /* mask for distance tree */
5016 uInt c
; /* bytes to copy */
5017 uInt d
; /* distance back to copy from */
5018 Bytef
*r
; /* copy source pointer */
5020 /* load input, output, bit values */
5023 /* initialize masks */
5024 ml
= inflate_mask
[bl
];
5025 md
= inflate_mask
[bd
];
5027 /* do until not enough input or output space for fast loop */
5028 do { /* assume called with m >= 258 && n >= 10 */
5029 /* get literal/length code */
5030 GRABBITS(20) /* max bits for literal/length code */
5031 if ((e
= (t
= tl
+ ((uInt
)b
& ml
))->exop
) == 0)
5034 Tracevv((stderr
, t
->base
>= 0x20 && t
->base
< 0x7f ?
5035 "inflate: * literal '%c'\n" :
5036 "inflate: * literal 0x%02x\n", t
->base
));
5037 *q
++ = (Byte
)t
->base
;
5045 /* get extra bits for length */
5047 c
= t
->base
+ ((uInt
)b
& inflate_mask
[e
]);
5049 Tracevv((stderr
, "inflate: * length %u\n", c
));
5051 /* decode distance base of block to copy */
5052 GRABBITS(15); /* max bits for distance code */
5053 e
= (t
= td
+ ((uInt
)b
& md
))->exop
;
5058 /* get extra bits to add to distance base */
5060 GRABBITS(e
) /* get extra bits (up to 13) */
5061 d
= t
->base
+ ((uInt
)b
& inflate_mask
[e
]);
5063 Tracevv((stderr
, "inflate: * distance %u\n", d
));
5067 if ((uInt
)(q
- s
->window
) >= d
) /* offset before dest */
5070 *q
++ = *r
++; c
--; /* minimum count is three, */
5071 *q
++ = *r
++; c
--; /* so unroll loop a little */
5073 else /* else offset after destination */
5075 e
= d
- (uInt
)(q
- s
->window
); /* bytes from offset to end */
5076 r
= s
->end
- e
; /* pointer to offset */
5077 if (c
> e
) /* if source crosses, */
5079 c
-= e
; /* copy to end of window */
5083 r
= s
->window
; /* copy rest from start of window */
5086 do { /* copy all or what's left */
5091 else if ((e
& 64) == 0)
5092 e
= (t
= t
->next
+ ((uInt
)b
& inflate_mask
[e
]))->exop
;
5095 z
->msg
= (char*)"invalid distance code";
5098 return Z_DATA_ERROR
;
5105 if ((e
= (t
= t
->next
+ ((uInt
)b
& inflate_mask
[e
]))->exop
) == 0)
5108 Tracevv((stderr
, t
->base
>= 0x20 && t
->base
< 0x7f ?
5109 "inflate: * literal '%c'\n" :
5110 "inflate: * literal 0x%02x\n", t
->base
));
5111 *q
++ = (Byte
)t
->base
;
5118 Tracevv((stderr
, "inflate: * end of block\n"));
5121 return Z_STREAM_END
;
5125 z
->msg
= (char*)"invalid literal/length code";
5128 return Z_DATA_ERROR
;
5131 } while (m
>= 258 && n
>= 10);
5133 /* not enough input or output--restore pointers and return */
5141 /* zutil.c -- target dependent utility functions for the compression library
5142 * Copyright (C) 1995-1996 Jean-loup Gailly.
5143 * For conditions of distribution and use, see copyright notice in zlib.h
5146 /* From: zutil.c,v 1.17 1996/07/24 13:41:12 me Exp $ */
5152 /* #include "zutil.h" */
5154 #ifndef NO_DUMMY_DECL
5155 struct internal_state
{int dummy
;}; /* for buggy compilers */
5159 extern void exit
OF((int));
5165 return ZLIB_VERSION
;
5172 fprintf(stderr
, "%s\n", m
);
5180 zmemcpy(Bytef
*dest
, Bytef
*source
, uInt len
)
5182 if (len
== 0) return;
5184 *dest
++ = *source
++; /* ??? to be unrolled */
5185 } while (--len
!= 0);
5189 zmemcmp(Bytef
*s1
, Bytef
*s2
, uInt len
)
5193 for (j
= 0; j
< len
; j
++) {
5194 if (s1
[j
] != s2
[j
]) return 2*(s1
[j
] > s2
[j
])-1;
5200 zmemzero(Bytef
*dest
, uInt len
)
5202 if (len
== 0) return;
5204 *dest
++ = 0; /* ??? to be unrolled */
5205 } while (--len
!= 0);
5210 #if (defined( __BORLANDC__) || !defined(SMALL_MEDIUM)) && !defined(__32BIT__)
5211 /* Small and medium model in Turbo C are for now limited to near allocation
5212 * with reduced MAX_WBITS and MAX_MEM_LEVEL
5216 /* Turbo C malloc() does not allow dynamic allocation of 64K bytes
5217 * and farmalloc(64K) returns a pointer with an offset of 8, so we
5218 * must fix the pointer. Warning: the pointer must be put back to its
5219 * original form in order to free it, use zcfree().
5225 local
int next_ptr
= 0;
5227 typedef struct ptr_table_s
{
5232 local ptr_table table
[MAX_PTR
];
5233 /* This table is used to remember the original form of pointers
5234 * to large buffers (64K). Such pointers are normalized with a zero offset.
5235 * Since MSDOS is not a preemptive multitasking OS, this table is not
5236 * protected from concurrent access. This hack doesn't work anyway on
5237 * a protected system like OS/2. Use Microsoft C instead.
5241 zcalloc(voidpf opaque
, unsigned items
, unsigned size
)
5243 voidpf buf
= opaque
; /* just to make some compilers happy */
5244 ulg bsize
= (ulg
)items
*size
;
5246 /* If we allocate less than 65520 bytes, we assume that farmalloc
5247 * will return a usable pointer which doesn't have to be normalized.
5249 if (bsize
< 65520L) {
5250 buf
= farmalloc(bsize
);
5251 if (*(ush
*)&buf
!= 0) return buf
;
5253 buf
= farmalloc(bsize
+ 16L);
5255 if (buf
== NULL
|| next_ptr
>= MAX_PTR
) return NULL
;
5256 table
[next_ptr
].org_ptr
= buf
;
5258 /* Normalize the pointer to seg:0 */
5259 *((ush
*)&buf
+1) += ((ush
)((uch
*)buf
-0) + 15) >> 4;
5261 table
[next_ptr
++].new_ptr
= buf
;
5266 zcfree(voidpf opaque
, voidpf ptr
)
5269 if (*(ush
*)&ptr
!= 0) { /* object < 64K */
5273 /* Find the original pointer */
5274 for (n
= 0; n
< next_ptr
; n
++) {
5275 if (ptr
!= table
[n
].new_ptr
) continue;
5277 farfree(table
[n
].org_ptr
);
5278 while (++n
< next_ptr
) {
5279 table
[n
-1] = table
[n
];
5284 ptr
= opaque
; /* just to make some compilers happy */
5285 Assert(0, "zcfree: ptr not found");
5288 #endif /* __TURBOC__ */
5291 #if defined(M_I86) && !defined(__32BIT__)
5292 /* Microsoft C in 16-bit mode */
5296 #if (!defined(_MSC_VER) || (_MSC_VER < 600))
5297 # define _halloc halloc
5298 # define _hfree hfree
5302 zcalloc(voidpf opaque
, unsigned items
, unsigned size
)
5304 if (opaque
) opaque
= 0; /* to make compiler happy */
5305 return _halloc((long)items
, size
);
5309 zcfree(voidpf opaque
, voidpf ptr
)
5311 if (opaque
) opaque
= 0; /* to make compiler happy */
5318 #ifndef MY_ZCALLOC /* Any system without a special alloc function */
5321 extern voidp calloc
OF((uInt items
, uInt size
));
5322 extern void free
OF((voidpf ptr
));
5326 zcalloc(voidpf opaque
, unsigned items
, unsigned size
)
5328 if (opaque
) items
+= size
- size
; /* make compiler happy */
5329 return (voidpf
)calloc(items
, size
);
5333 zcfree(voidpf opaque
, voidpf ptr
)
5336 if (opaque
) return; /* make compiler happy */
5339 #endif /* MY_ZCALLOC */
5343 /* adler32.c -- compute the Adler-32 checksum of a data stream
5344 * Copyright (C) 1995-1996 Mark Adler
5345 * For conditions of distribution and use, see copyright notice in zlib.h
5348 /* From: adler32.c,v 1.10 1996/05/22 11:52:18 me Exp $ */
5350 /* #include "zlib.h" */
5352 #define BASE 65521L /* largest prime smaller than 65536 */
5354 /* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
5356 #define DO1(buf,i) {s1 += buf[i]; s2 += s1;}
5357 #define DO2(buf,i) DO1(buf,i); DO1(buf,i+1);
5358 #define DO4(buf,i) DO2(buf,i); DO2(buf,i+2);
5359 #define DO8(buf,i) DO4(buf,i); DO4(buf,i+4);
5360 #define DO16(buf) DO8(buf,0); DO8(buf,8);
5362 /* ========================================================================= */
5364 adler32(uLong adler
, const Bytef
*buf
, uInt len
)
5366 unsigned long s1
= adler
& 0xffff;
5367 unsigned long s2
= (adler
>> 16) & 0xffff;
5370 if (buf
== Z_NULL
) return 1L;
5373 k
= len
< NMAX
? len
: NMAX
;
5387 return (s2
<< 16) | s1
;
5391 MODULE_VERSION(zlib
, 1);