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Diffstat (limited to 'sys/net/zlib.c')
| -rw-r--r-- | sys/net/zlib.c | 4636 |
1 files changed, 4636 insertions, 0 deletions
diff --git a/sys/net/zlib.c b/sys/net/zlib.c new file mode 100644 index 0000000..b9da5f9 --- /dev/null +++ b/sys/net/zlib.c @@ -0,0 +1,4636 @@ +/* + * This file is derived from various .h and .c files from the zlib-0.95 + * distribution by Jean-loup Gailly and Mark Adler, with some additions + * by Paul Mackerras to aid in implementing Deflate compression and + * decompression for PPP packets. See zlib.h for conditions of + * distribution and use. + * + * Changes that have been made include: + * - changed functions not used outside this file to "local" + * - added minCompression parameter to deflateInit2 + * - added Z_PACKET_FLUSH (see zlib.h for details) + * - added inflateIncomp + * + * $Id: zlib.c,v 1.7 1997/05/22 06:44:39 paulus Exp $ + */ + +/* + * ==FILEVERSION 970501== + * + * This marker is used by the Linux installation script to determine + * whether an up-to-date version of this file is already installed. + */ + +/*+++++*/ +/* zutil.h -- internal interface and configuration of the compression library + * Copyright (C) 1995 Jean-loup Gailly. + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* WARNING: this file should *not* be used by applications. It is + part of the implementation of the compression library and is + subject to change. Applications should only use zlib.h. + */ + +/* From: zutil.h,v 1.9 1995/05/03 17:27:12 jloup Exp */ + +#define _Z_UTIL_H + +#include "zlib.h" + +#ifndef local +# define local static +#endif +/* compile with -Dlocal if your debugger can't find static symbols */ + +#define FAR + +typedef unsigned char uch; +typedef uch FAR uchf; +typedef unsigned short ush; +typedef ush FAR ushf; +typedef unsigned long ulg; + +extern char *z_errmsg[]; /* indexed by 1-zlib_error */ + +#define ERR_RETURN(strm,err) return (strm->msg=z_errmsg[1-err], err) +/* To be used only when the state is known to be valid */ + +#ifndef NULL +#define NULL ((void *) 0) +#endif + + /* common constants */ + +#define DEFLATED 8 + +#ifndef DEF_WBITS +# define DEF_WBITS MAX_WBITS +#endif +/* default windowBits for decompression. MAX_WBITS is for compression only */ + +#if MAX_MEM_LEVEL >= 8 +# define DEF_MEM_LEVEL 8 +#else +# define DEF_MEM_LEVEL MAX_MEM_LEVEL +#endif +/* default memLevel */ + +#define STORED_BLOCK 0 +#define STATIC_TREES 1 +#define DYN_TREES 2 +/* The three kinds of block type */ + +#define MIN_MATCH 3 +#define MAX_MATCH 258 +/* The minimum and maximum match lengths */ + + /* functions */ + +#if defined(KERNEL) || defined(_KERNEL) +#include <sys/types.h> +#include <sys/time.h> +#include <sys/systm.h> +# define zmemcpy(d, s, n) bcopy((s), (d), (n)) +# define zmemzero bzero + +#else +#if defined(__KERNEL__) +/* Assume this is Linux */ +#include <linux/string.h> +#define zmemcpy memcpy +#define zmemzero(dest, len) memset(dest, 0, len) + +#else /* not kernel */ +#if defined(STDC) && !defined(HAVE_MEMCPY) && !defined(NO_MEMCPY) +# define HAVE_MEMCPY +#endif +#ifdef HAVE_MEMCPY +# define zmemcpy memcpy +# define zmemzero(dest, len) memset(dest, 0, len) +#else + extern void zmemcpy OF((Bytef* dest, Bytef* source, uInt len)); + extern void zmemzero OF((Bytef* dest, uInt len)); +#endif +#endif /* __KERNEL__ */ +#endif /* KERNEL */ + +/* Diagnostic functions */ +#ifdef DEBUG_ZLIB +# include <stdio.h> +# ifndef verbose +# define verbose 0 +# endif +# define Assert(cond,msg) {if(!(cond)) z_error(msg);} +# define Trace(x) fprintf x +# define Tracev(x) {if (verbose) fprintf x ;} +# define Tracevv(x) {if (verbose>1) fprintf x ;} +# define Tracec(c,x) {if (verbose && (c)) fprintf x ;} +# define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;} +#else +# define Assert(cond,msg) +# define Trace(x) +# define Tracev(x) +# define Tracevv(x) +# define Tracec(c,x) +# define Tracecv(c,x) +#endif + + +typedef uLong (*check_func) OF((uLong check, Bytef *buf, uInt len)); + +/* voidpf zcalloc OF((voidpf opaque, unsigned items, unsigned size)); */ +/* void zcfree OF((voidpf opaque, voidpf ptr)); */ + +#define ZALLOC(strm, items, size) \ + (*((strm)->zalloc))((strm)->opaque, (items), (size)) +#define ZALLOC_INIT(strm, items, size) \ + (*((strm)->zalloc_init))((strm)->opaque, (items), (size)) +#define ZFREE(strm, addr, size) \ + (*((strm)->zfree))((strm)->opaque, (voidpf)(addr), (size)) +#define TRY_FREE(s, p, n) {if (p) ZFREE(s, p, n);} + +/* deflate.h -- internal compression state + * Copyright (C) 1995 Jean-loup Gailly + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* WARNING: this file should *not* be used by applications. It is + part of the implementation of the compression library and is + subject to change. Applications should only use zlib.h. + */ + + +/*+++++*/ +/* From: deflate.h,v 1.5 1995/05/03 17:27:09 jloup Exp */ + +/* =========================================================================== + * Internal compression state. + */ + +/* Data type */ +#define Z_BINARY 0 +#define ASCII 1 +#define UNKNOWN 2 + +#define LENGTH_CODES 29 +/* number of length codes, not counting the special END_BLOCK code */ + +#define LITERALS 256 +/* number of literal bytes 0..255 */ + +#define L_CODES (LITERALS+1+LENGTH_CODES) +/* number of Literal or Length codes, including the END_BLOCK code */ + +#define D_CODES 30 +/* number of distance codes */ + +#define BL_CODES 19 +/* number of codes used to transfer the bit lengths */ + +#define HEAP_SIZE (2*L_CODES+1) +/* maximum heap size */ + +#define MAX_BITS 15 +/* All codes must not exceed MAX_BITS bits */ + +#define INIT_STATE 42 +#define BUSY_STATE 113 +#define FLUSH_STATE 124 +#define FINISH_STATE 666 +/* Stream status */ + + +/* Data structure describing a single value and its code string. */ +typedef struct ct_data_s { + union { + ush freq; /* frequency count */ + ush code; /* bit string */ + } fc; + union { + ush dad; /* father node in Huffman tree */ + ush len; /* length of bit string */ + } dl; +} FAR ct_data; + +#define Freq fc.freq +#define Code fc.code +#define Dad dl.dad +#define Len dl.len + +typedef struct static_tree_desc_s static_tree_desc; + +typedef struct tree_desc_s { + ct_data *dyn_tree; /* the dynamic tree */ + int max_code; /* largest code with non zero frequency */ + static_tree_desc *stat_desc; /* the corresponding static tree */ +} FAR tree_desc; + +typedef ush Pos; +typedef Pos FAR Posf; +typedef unsigned IPos; + +/* A Pos is an index in the character window. We use short instead of int to + * save space in the various tables. IPos is used only for parameter passing. + */ + +typedef struct deflate_state { + z_stream *strm; /* pointer back to this zlib stream */ + int status; /* as the name implies */ + Bytef *pending_buf; /* output still pending */ + Bytef *pending_out; /* next pending byte to output to the stream */ + int pending; /* nb of bytes in the pending buffer */ + uLong adler; /* adler32 of uncompressed data */ + int noheader; /* suppress zlib header and adler32 */ + Byte data_type; /* UNKNOWN, Z_BINARY or ASCII */ + Byte method; /* STORED (for zip only) or DEFLATED */ + int minCompr; /* min size decrease for Z_FLUSH_NOSTORE */ + + /* used by deflate.c: */ + + uInt w_size; /* LZ77 window size (32K by default) */ + uInt w_bits; /* log2(w_size) (8..16) */ + uInt w_mask; /* w_size - 1 */ + + Bytef *window; + /* Sliding window. Input bytes are read into the second half of the window, + * and move to the first half later to keep a dictionary of at least wSize + * bytes. With this organization, matches are limited to a distance of + * wSize-MAX_MATCH bytes, but this ensures that IO is always + * performed with a length multiple of the block size. Also, it limits + * the window size to 64K, which is quite useful on MSDOS. + * To do: use the user input buffer as sliding window. + */ + + ulg window_size; + /* Actual size of window: 2*wSize, except when the user input buffer + * is directly used as sliding window. + */ + + Posf *prev; + /* Link to older string with same hash index. To limit the size of this + * array to 64K, this link is maintained only for the last 32K strings. + * An index in this array is thus a window index modulo 32K. + */ + + Posf *head; /* Heads of the hash chains or NIL. */ + + uInt ins_h; /* hash index of string to be inserted */ + uInt hash_size; /* number of elements in hash table */ + uInt hash_bits; /* log2(hash_size) */ + uInt hash_mask; /* hash_size-1 */ + + uInt hash_shift; + /* Number of bits by which ins_h must be shifted at each input + * step. It must be such that after MIN_MATCH steps, the oldest + * byte no longer takes part in the hash key, that is: + * hash_shift * MIN_MATCH >= hash_bits + */ + + long block_start; + /* Window position at the beginning of the current output block. Gets + * negative when the window is moved backwards. + */ + + uInt match_length; /* length of best match */ + IPos prev_match; /* previous match */ + int match_available; /* set if previous match exists */ + uInt strstart; /* start of string to insert */ + uInt match_start; /* start of matching string */ + uInt lookahead; /* number of valid bytes ahead in window */ + + uInt prev_length; + /* Length of the best match at previous step. Matches not greater than this + * are discarded. This is used in the lazy match evaluation. + */ + + uInt max_chain_length; + /* To speed up deflation, hash chains are never searched beyond this + * length. A higher limit improves compression ratio but degrades the + * speed. + */ + + uInt max_lazy_match; + /* Attempt to find a better match only when the current match is strictly + * smaller than this value. This mechanism is used only for compression + * levels >= 4. + */ +# define max_insert_length max_lazy_match + /* Insert new strings in the hash table only if the match length is not + * greater than this length. This saves time but degrades compression. + * max_insert_length is used only for compression levels <= 3. + */ + + int level; /* compression level (1..9) */ + int strategy; /* favor or force Huffman coding*/ + + uInt good_match; + /* Use a faster search when the previous match is longer than this */ + + int nice_match; /* Stop searching when current match exceeds this */ + + /* used by trees.c: */ + /* Didn't use ct_data typedef below to supress compiler warning */ + struct ct_data_s dyn_ltree[HEAP_SIZE]; /* literal and length tree */ + struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */ + struct ct_data_s bl_tree[2*BL_CODES+1]; /* Huffman tree for bit lengths */ + + struct tree_desc_s l_desc; /* desc. for literal tree */ + struct tree_desc_s d_desc; /* desc. for distance tree */ + struct tree_desc_s bl_desc; /* desc. for bit length tree */ + + ush bl_count[MAX_BITS+1]; + /* number of codes at each bit length for an optimal tree */ + + int heap[2*L_CODES+1]; /* heap used to build the Huffman trees */ + int heap_len; /* number of elements in the heap */ + int heap_max; /* element of largest frequency */ + /* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used. + * The same heap array is used to build all trees. + */ + + uch depth[2*L_CODES+1]; + /* Depth of each subtree used as tie breaker for trees of equal frequency + */ + + uchf *l_buf; /* buffer for literals or lengths */ + + uInt lit_bufsize; + /* Size of match buffer for literals/lengths. There are 4 reasons for + * limiting lit_bufsize to 64K: + * - frequencies can be kept in 16 bit counters + * - if compression is not successful for the first block, all input + * data is still in the window so we can still emit a stored block even + * when input comes from standard input. (This can also be done for + * all blocks if lit_bufsize is not greater than 32K.) + * - if compression is not successful for a file smaller than 64K, we can + * even emit a stored file instead of a stored block (saving 5 bytes). + * This is applicable only for zip (not gzip or zlib). + * - creating new Huffman trees less frequently may not provide fast + * adaptation to changes in the input data statistics. (Take for + * example a binary file with poorly compressible code followed by + * a highly compressible string table.) Smaller buffer sizes give + * fast adaptation but have of course the overhead of transmitting + * trees more frequently. + * - I can't count above 4 + */ + + uInt last_lit; /* running index in l_buf */ + + ushf *d_buf; + /* Buffer for distances. To simplify the code, d_buf and l_buf have + * the same number of elements. To use different lengths, an extra flag + * array would be necessary. + */ + + ulg opt_len; /* bit length of current block with optimal trees */ + ulg static_len; /* bit length of current block with static trees */ + ulg compressed_len; /* total bit length of compressed file */ + uInt matches; /* number of string matches in current block */ + int last_eob_len; /* bit length of EOB code for last block */ + +#ifdef DEBUG_ZLIB + ulg bits_sent; /* bit length of the compressed data */ +#endif + + ush bi_buf; + /* Output buffer. bits are inserted starting at the bottom (least + * significant bits). + */ + int bi_valid; + /* Number of valid bits in bi_buf. All bits above the last valid bit + * are always zero. + */ + + uInt blocks_in_packet; + /* Number of blocks produced since the last time Z_PACKET_FLUSH + * was used. + */ + +} FAR deflate_state; + +/* Output a byte on the stream. + * IN assertion: there is enough room in pending_buf. + */ +#define put_byte(s, c) {s->pending_buf[s->pending++] = (c);} + + +#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1) +/* Minimum amount of lookahead, except at the end of the input file. + * See deflate.c for comments about the MIN_MATCH+1. + */ + +#define MAX_DIST(s) ((s)->w_size-MIN_LOOKAHEAD) +/* In order to simplify the code, particularly on 16 bit machines, match + * distances are limited to MAX_DIST instead of WSIZE. + */ + + /* in trees.c */ +local void ct_init OF((deflate_state *s)); +local int ct_tally OF((deflate_state *s, int dist, int lc)); +local ulg ct_flush_block OF((deflate_state *s, charf *buf, ulg stored_len, + int flush)); +local void ct_align OF((deflate_state *s)); +local void ct_stored_block OF((deflate_state *s, charf *buf, ulg stored_len, + int eof)); +local void ct_stored_type_only OF((deflate_state *s)); + + +/*+++++*/ +/* deflate.c -- compress data using the deflation algorithm + * Copyright (C) 1995 Jean-loup Gailly. + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* + * ALGORITHM + * + * The "deflation" process depends on being able to identify portions + * of the input text which are identical to earlier input (within a + * sliding window trailing behind the input currently being processed). + * + * The most straightforward technique turns out to be the fastest for + * most input files: try all possible matches and select the longest. + * The key feature of this algorithm is that insertions into the string + * dictionary are very simple and thus fast, and deletions are avoided + * completely. Insertions are performed at each input character, whereas + * string matches are performed only when the previous match ends. So it + * is preferable to spend more time in matches to allow very fast string + * insertions and avoid deletions. The matching algorithm for small + * strings is inspired from that of Rabin & Karp. A brute force approach + * is used to find longer strings when a small match has been found. + * A similar algorithm is used in comic (by Jan-Mark Wams) and freeze + * (by Leonid Broukhis). + * A previous version of this file used a more sophisticated algorithm + * (by Fiala and Greene) which is guaranteed to run in linear amortized + * time, but has a larger average cost, uses more memory and is patented. + * However the F&G algorithm may be faster for some highly redundant + * files if the parameter max_chain_length (described below) is too large. + * + * ACKNOWLEDGEMENTS + * + * The idea of lazy evaluation of matches is due to Jan-Mark Wams, and + * I found it in 'freeze' written by Leonid Broukhis. + * Thanks to many people for bug reports and testing. + * + * REFERENCES + * + * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification". + * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc + * + * A description of the Rabin and Karp algorithm is given in the book + * "Algorithms" by R. Sedgewick, Addison-Wesley, p252. + * + * Fiala,E.R., and Greene,D.H. + * Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595 + * + */ + +/* From: deflate.c,v 1.8 1995/05/03 17:27:08 jloup Exp */ + +local char zlib_copyright[] = " deflate Copyright 1995 Jean-loup Gailly "; +/* + If you use the zlib library in a product, an acknowledgment is welcome + in the documentation of your product. If for some reason you cannot + include such an acknowledgment, I would appreciate that you keep this + copyright string in the executable of your product. + */ + +#define NIL 0 +/* Tail of hash chains */ + +#ifndef TOO_FAR +# define TOO_FAR 4096 +#endif +/* Matches of length 3 are discarded if their distance exceeds TOO_FAR */ + +#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1) +/* Minimum amount of lookahead, except at the end of the input file. + * See deflate.c for comments about the MIN_MATCH+1. + */ + +/* Values for max_lazy_match, good_match and max_chain_length, depending on + * the desired pack level (0..9). The values given below have been tuned to + * exclude worst case performance for pathological files. Better values may be + * found for specific files. + */ + +typedef struct config_s { + ush good_length; /* reduce lazy search above this match length */ + ush max_lazy; /* do not perform lazy search above this match length */ + ush nice_length; /* quit search above this match length */ + ush max_chain; +} config; + +local config configuration_table[10] = { +/* good lazy nice chain */ +/* 0 */ {0, 0, 0, 0}, /* store only */ +/* 1 */ {4, 4, 8, 4}, /* maximum speed, no lazy matches */ +/* 2 */ {4, 5, 16, 8}, +/* 3 */ {4, 6, 32, 32}, + +/* 4 */ {4, 4, 16, 16}, /* lazy matches */ +/* 5 */ {8, 16, 32, 32}, +/* 6 */ {8, 16, 128, 128}, +/* 7 */ {8, 32, 128, 256}, +/* 8 */ {32, 128, 258, 1024}, +/* 9 */ {32, 258, 258, 4096}}; /* maximum compression */ + +/* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4 + * For deflate_fast() (levels <= 3) good is ignored and lazy has a different + * meaning. + */ + +#define EQUAL 0 +/* result of memcmp for equal strings */ + +/* =========================================================================== + * Prototypes for local functions. + */ + +local void fill_window OF((deflate_state *s)); +local int deflate_fast OF((deflate_state *s, int flush)); +local int deflate_slow OF((deflate_state *s, int flush)); +local void lm_init OF((deflate_state *s)); +local int longest_match OF((deflate_state *s, IPos cur_match)); +local void putShortMSB OF((deflate_state *s, uInt b)); +local void flush_pending OF((z_stream *strm)); +local int read_buf OF((z_stream *strm, charf *buf, unsigned size)); +#ifdef ASMV + void match_init OF((void)); /* asm code initialization */ +#endif + +#ifdef DEBUG_ZLIB +local void check_match OF((deflate_state *s, IPos start, IPos match, + int length)); +#endif + + +/* =========================================================================== + * Update a hash value with the given input byte + * IN assertion: all calls to to UPDATE_HASH are made with consecutive + * input characters, so that a running hash key can be computed from the + * previous key instead of complete recalculation each time. + */ +#define UPDATE_HASH(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask) + + +/* =========================================================================== + * Insert string str in the dictionary and set match_head to the previous head + * of the hash chain (the most recent string with same hash key). Return + * the previous length of the hash chain. + * IN assertion: all calls to to INSERT_STRING are made with consecutive + * input characters and the first MIN_MATCH bytes of str are valid + * (except for the last MIN_MATCH-1 bytes of the input file). + */ +#define INSERT_STRING(s, str, match_head) \ + (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \ + s->prev[(str) & s->w_mask] = match_head = s->head[s->ins_h], \ + s->head[s->ins_h] = (str)) + +/* =========================================================================== + * Initialize the hash table (avoiding 64K overflow for 16 bit systems). + * prev[] will be initialized on the fly. + */ +#define CLEAR_HASH(s) \ + s->head[s->hash_size-1] = NIL; \ + zmemzero((charf *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head)); + +/* ========================================================================= */ +int deflateInit (strm, level) + z_stream *strm; + int level; +{ + return deflateInit2 (strm, level, DEFLATED, MAX_WBITS, DEF_MEM_LEVEL, + 0, 0); + /* To do: ignore strm->next_in if we use it as window */ +} + +/* ========================================================================= */ +int deflateInit2 (strm, level, method, windowBits, memLevel, + strategy, minCompression) + z_stream *strm; + int level; + int method; + int windowBits; + int memLevel; + int strategy; + int minCompression; +{ + deflate_state *s; + int noheader = 0; + + if (strm == Z_NULL) return Z_STREAM_ERROR; + + strm->msg = Z_NULL; +/* if (strm->zalloc == Z_NULL) strm->zalloc = zcalloc; */ +/* if (strm->zfree == Z_NULL) strm->zfree = zcfree; */ + + if (level == Z_DEFAULT_COMPRESSION) level = 6; + + if (windowBits < 0) { /* undocumented feature: suppress zlib header */ + noheader = 1; + windowBits = -windowBits; + } + if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != DEFLATED || + windowBits < 8 || windowBits > 15 || level < 1 || level > 9) { + return Z_STREAM_ERROR; + } + s = (deflate_state *) ZALLOC_INIT(strm, 1, sizeof(deflate_state)); + if (s == Z_NULL) return Z_MEM_ERROR; + strm->state = (struct internal_state FAR *)s; + s->strm = strm; + + s->noheader = noheader; + s->w_bits = windowBits; + s->w_size = 1 << s->w_bits; + s->w_mask = s->w_size - 1; + + s->hash_bits = memLevel + 7; + s->hash_size = 1 << s->hash_bits; + s->hash_mask = s->hash_size - 1; + s->hash_shift = ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH); + + s->window = (Bytef *) ZALLOC_INIT(strm, s->w_size, 2*sizeof(Byte)); + s->prev = (Posf *) ZALLOC_INIT(strm, s->w_size, sizeof(Pos)); + s->head = (Posf *) ZALLOC_INIT(strm, s->hash_size, sizeof(Pos)); + + s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */ + + s->pending_buf = (uchf *) ZALLOC_INIT(strm, s->lit_bufsize, 2*sizeof(ush)); + + if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL || + s->pending_buf == Z_NULL) { + strm->msg = z_errmsg[1-Z_MEM_ERROR]; + deflateEnd (strm); + return Z_MEM_ERROR; + } + s->d_buf = (ushf *) &(s->pending_buf[s->lit_bufsize]); + s->l_buf = (uchf *) &(s->pending_buf[3*s->lit_bufsize]); + /* We overlay pending_buf and d_buf+l_buf. This works since the average + * output size for (length,distance) codes is <= 32 bits (worst case + * is 15+15+13=33). + */ + + s->level = level; + s->strategy = strategy; + s->method = (Byte)method; + s->minCompr = minCompression; + s->blocks_in_packet = 0; + + return deflateReset(strm); +} + +/* ========================================================================= */ +int deflateReset (strm) + z_stream *strm; +{ + deflate_state *s; + + if (strm == Z_NULL || strm->state == Z_NULL || + strm->zalloc == Z_NULL || strm->zfree == Z_NULL || + strm->zalloc_init == Z_NULL) return Z_STREAM_ERROR; + + strm->total_in = strm->total_out = 0; + strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */ + strm->data_type = Z_UNKNOWN; + + s = (deflate_state *)strm->state; + s->pending = 0; + s->pending_out = s->pending_buf; + + if (s->noheader < 0) { + s->noheader = 0; /* was set to -1 by deflate(..., Z_FINISH); */ + } + s->status = s->noheader ? BUSY_STATE : INIT_STATE; + s->adler = 1; + + ct_init(s); + lm_init(s); + + return Z_OK; +} + +/* ========================================================================= + * Put a short in the pending buffer. The 16-bit value is put in MSB order. + * IN assertion: the stream state is correct and there is enough room in + * pending_buf. + */ +local void putShortMSB (s, b) + deflate_state *s; + uInt b; +{ + put_byte(s, (Byte)(b >> 8)); + put_byte(s, (Byte)(b & 0xff)); +} + +/* ========================================================================= + * Flush as much pending output as possible. + */ +local void flush_pending(strm) + z_stream *strm; +{ + deflate_state *state = (deflate_state *) strm->state; + unsigned len = state->pending; + + if (len > strm->avail_out) len = strm->avail_out; + if (len == 0) return; + + if (strm->next_out != NULL) { + zmemcpy(strm->next_out, state->pending_out, len); + strm->next_out += len; + } + state->pending_out += len; + strm->total_out += len; + strm->avail_out -= len; + state->pending -= len; + if (state->pending == 0) { + state->pending_out = state->pending_buf; + } +} + +/* ========================================================================= */ +int deflate (strm, flush) + z_stream *strm; + int flush; +{ + deflate_state *state = (deflate_state *) strm->state; + + if (strm == Z_NULL || state == Z_NULL) return Z_STREAM_ERROR; + + if (strm->next_in == Z_NULL && strm->avail_in != 0) { + ERR_RETURN(strm, Z_STREAM_ERROR); + } + if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR); + + state->strm = strm; /* just in case */ + + /* Write the zlib header */ + if (state->status == INIT_STATE) { + + uInt header = (DEFLATED + ((state->w_bits-8)<<4)) << 8; + uInt level_flags = (state->level-1) >> 1; + + if (level_flags > 3) level_flags = 3; + header |= (level_flags << 6); + header += 31 - (header % 31); + + state->status = BUSY_STATE; + putShortMSB(state, header); + } + + /* Flush as much pending output as possible */ + if (state->pending != 0) { + flush_pending(strm); + if (strm->avail_out == 0) return Z_OK; + } + + /* If we came back in here to get the last output from + * a previous flush, we're done for now. + */ + if (state->status == FLUSH_STATE) { + state->status = BUSY_STATE; + if (flush != Z_NO_FLUSH && flush != Z_FINISH) + return Z_OK; + } + + /* User must not provide more input after the first FINISH: */ + if (state->status == FINISH_STATE && strm->avail_in != 0) { + ERR_RETURN(strm, Z_BUF_ERROR); + } + + /* Start a new block or continue the current one. + */ + if (strm->avail_in != 0 || state->lookahead != 0 || + (flush == Z_FINISH && state->status != FINISH_STATE)) { + int quit; + + if (flush == Z_FINISH) { + state->status = FINISH_STATE; + } + if (state->level <= 3) { + quit = deflate_fast(state, flush); + } else { + quit = deflate_slow(state, flush); + } + if (quit || strm->avail_out == 0) + return Z_OK; + /* If flush != Z_NO_FLUSH && avail_out == 0, the next call + * of deflate should use the same flush parameter to make sure + * that the flush is complete. So we don't have to output an + * empty block here, this will be done at next call. This also + * ensures that for a very small output buffer, we emit at most + * one empty block. + */ + } + + /* If a flush was requested, we have a little more to output now. */ + if (flush != Z_NO_FLUSH && flush != Z_FINISH + && state->status != FINISH_STATE) { + switch (flush) { + case Z_PARTIAL_FLUSH: + ct_align(state); + break; + case Z_PACKET_FLUSH: + /* Output just the 3-bit `stored' block type value, + but not a zero length. */ + ct_stored_type_only(state); + break; + default: + ct_stored_block(state, (char*)0, 0L, 0); + /* For a full flush, this empty block will be recognized + * as a special marker by inflate_sync(). + */ + if (flush == Z_FULL_FLUSH) { + CLEAR_HASH(state); /* forget history */ + } + } + flush_pending(strm); + if (strm->avail_out == 0) { + /* We'll have to come back to get the rest of the output; + * this ensures we don't output a second zero-length stored + * block (or whatever). + */ + state->status = FLUSH_STATE; + return Z_OK; + } + } + + Assert(strm->avail_out > 0, "bug2"); + + if (flush != Z_FINISH) return Z_OK; + if (state->noheader) return Z_STREAM_END; + + /* Write the zlib trailer (adler32) */ + putShortMSB(state, (uInt)(state->adler >> 16)); + putShortMSB(state, (uInt)(state->adler & 0xffff)); + flush_pending(strm); + /* If avail_out is zero, the application will call deflate again + * to flush the rest. + */ + state->noheader = -1; /* write the trailer only once! */ + return state->pending != 0 ? Z_OK : Z_STREAM_END; +} + +/* ========================================================================= */ +int deflateEnd (strm) + z_stream *strm; +{ + deflate_state *state = (deflate_state *) strm->state; + + if (strm == Z_NULL || state == Z_NULL) return Z_STREAM_ERROR; + + TRY_FREE(strm, state->window, state->w_size * 2 * sizeof(Byte)); + TRY_FREE(strm, state->prev, state->w_size * sizeof(Pos)); + TRY_FREE(strm, state->head, state->hash_size * sizeof(Pos)); + TRY_FREE(strm, state->pending_buf, state->lit_bufsize * 2 * sizeof(ush)); + + ZFREE(strm, state, sizeof(deflate_state)); + strm->state = Z_NULL; + + return Z_OK; +} + +/* =========================================================================== + * Read a new buffer from the current input stream, update the adler32 + * and total number of bytes read. + */ +local int read_buf(strm, buf, size) + z_stream *strm; + charf *buf; + unsigned size; +{ + unsigned len = strm->avail_in; + deflate_state *state = (deflate_state *) strm->state; + + if (len > size) len = size; + if (len == 0) return 0; + + strm->avail_in -= len; + + if (!state->noheader) { + state->adler = adler32(state->adler, strm->next_in, len); + } + zmemcpy(buf, strm->next_in, len); + strm->next_in += len; + strm->total_in += len; + + return (int)len; +} + +/* =========================================================================== + * Initialize the "longest match" routines for a new zlib stream + */ +local void lm_init (s) + deflate_state *s; +{ + s->window_size = (ulg)2L*s->w_size; + + CLEAR_HASH(s); + + /* Set the default configuration parameters: + */ + s->max_lazy_match = configuration_table[s->level].max_lazy; + s->good_match = configuration_table[s->level].good_length; + s->nice_match = configuration_table[s->level].nice_length; + s->max_chain_length = configuration_table[s->level].max_chain; + + s->strstart = 0; + s->block_start = 0L; + s->lookahead = 0; + s->match_length = MIN_MATCH-1; + s->match_available = 0; + s->ins_h = 0; +#ifdef ASMV + match_init(); /* initialize the asm code */ +#endif +} + +/* =========================================================================== + * Set match_start to the longest match starting at the given string and + * return its length. Matches shorter or equal to prev_length are discarded, + * in which case the result is equal to prev_length and match_start is + * garbage. + * IN assertions: cur_match is the head of the hash chain for the current + * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1 + */ +#ifndef ASMV +/* For 80x86 and 680x0, an optimized version will be provided in match.asm or + * match.S. The code will be functionally equivalent. + */ +local int longest_match(s, cur_match) + deflate_state *s; + IPos cur_match; /* current match */ +{ + unsigned chain_length = s->max_chain_length;/* max hash chain length */ + register Bytef *scan = s->window + s->strstart; /* current string */ + register Bytef *match; /* matched string */ + register int len; /* length of current match */ + int best_len = s->prev_length; /* best match length so far */ + IPos limit = s->strstart > (IPos)MAX_DIST(s) ? + s->strstart - (IPos)MAX_DIST(s) : NIL; + /* Stop when cur_match becomes <= limit. To simplify the code, + * we prevent matches with the string of window index 0. + */ + Posf *prev = s->prev; + uInt wmask = s->w_mask; + +#ifdef UNALIGNED_OK + /* Compare two bytes at a time. Note: this is not always beneficial. + * Try with and without -DUNALIGNED_OK to check. + */ + register Bytef *strend = s->window + s->strstart + MAX_MATCH - 1; + register ush scan_start = *(ushf*)scan; + register ush scan_end = *(ushf*)(scan+best_len-1); +#else + register Bytef *strend = s->window + s->strstart + MAX_MATCH; + register Byte scan_end1 = scan[best_len-1]; + register Byte scan_end = scan[best_len]; +#endif + + /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16. + * It is easy to get rid of this optimization if necessary. + */ + Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever"); + + /* Do not waste too much time if we already have a good match: */ + if (s->prev_length >= s->good_match) { + chain_length >>= 2; + } + Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead"); + + do { + Assert(cur_match < s->strstart, "no future"); + match = s->window + cur_match; + + /* Skip to next match if the match length cannot increase + * or if the match length is less than 2: + */ +#if (defined(UNALIGNED_OK) && MAX_MATCH == 258) + /* This code assumes sizeof(unsigned short) == 2. Do not use + * UNALIGNED_OK if your compiler uses a different size. + */ + if (*(ushf*)(match+best_len-1) != scan_end || + *(ushf*)match != scan_start) continue; + + /* It is not necessary to compare scan[2] and match[2] since they are + * always equal when the other bytes match, given that the hash keys + * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at + * strstart+3, +5, ... up to strstart+257. We check for insufficient + * lookahead only every 4th comparison; the 128th check will be made + * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is + * necessary to put more guard bytes at the end of the window, or + * to check more often for insufficient lookahead. + */ + Assert(scan[2] == match[2], "scan[2]?"); + scan++, match++; + do { + } while (*(ushf*)(scan+=2) == *(ushf*)(match+=2) && + *(ushf*)(scan+=2) == *(ushf*)(match+=2) && + *(ushf*)(scan+=2) == *(ushf*)(match+=2) && + *(ushf*)(scan+=2) == *(ushf*)(match+=2) && + scan < strend); + /* The funny "do {}" generates better code on most compilers */ + + /* Here, scan <= window+strstart+257 */ + Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan"); + if (*scan == *match) scan++; + + len = (MAX_MATCH - 1) - (int)(strend-scan); + scan = strend - (MAX_MATCH-1); + +#else /* UNALIGNED_OK */ + + if (match[best_len] != scan_end || + match[best_len-1] != scan_end1 || + *match != *scan || + *++match != scan[1]) continue; + + /* The check at best_len-1 can be removed because it will be made + * again later. (This heuristic is not always a win.) + * It is not necessary to compare scan[2] and match[2] since they + * are always equal when the other bytes match, given that + * the hash keys are equal and that HASH_BITS >= 8. + */ + scan += 2, match++; + Assert(*scan == *match, "match[2]?"); + + /* We check for insufficient lookahead only every 8th comparison; + * the 256th check will be made at strstart+258. + */ + do { + } while (*++scan == *++match && *++scan == *++match && + *++scan == *++match && *++scan == *++match && + *++scan == *++match && *++scan == *++match && + *++scan == *++match && *++scan == *++match && + scan < strend); + + Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan"); + + len = MAX_MATCH - (int)(strend - scan); + scan = strend - MAX_MATCH; + +#endif /* UNALIGNED_OK */ + + if (len > best_len) { + s->match_start = cur_match; + best_len = len; + if (len >= s->nice_match) break; +#ifdef UNALIGNED_OK + scan_end = *(ushf*)(scan+best_len-1); +#else + scan_end1 = scan[best_len-1]; + scan_end = scan[best_len]; +#endif + } + } while ((cur_match = prev[cur_match & wmask]) > limit + && --chain_length != 0); + + return best_len; +} +#endif /* ASMV */ + +#ifdef DEBUG_ZLIB +/* =========================================================================== + * Check that the match at match_start is indeed a match. + */ +local void check_match(s, start, match, length) + deflate_state *s; + IPos start, match; + int length; +{ + /* check that the match is indeed a match */ + if (memcmp((charf *)s->window + match, + (charf *)s->window + start, length) != EQUAL) { + fprintf(stderr, + " start %u, match %u, length %d\n", + start, match, length); + do { fprintf(stderr, "%c%c", s->window[match++], + s->window[start++]); } while (--length != 0); + z_error("invalid match"); + } + if (verbose > 1) { + fprintf(stderr,"\\[%d,%d]", start-match, length); + do { putc(s->window[start++], stderr); } while (--length != 0); + } +} +#else +# define check_match(s, start, match, length) +#endif + +/* =========================================================================== + * Fill the window when the lookahead becomes insufficient. + * Updates strstart and lookahead. + * + * IN assertion: lookahead < MIN_LOOKAHEAD + * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD + * At least one byte has been read, or avail_in == 0; reads are + * performed for at least two bytes (required for the zip translate_eol + * option -- not supported here). + */ +local void fill_window(s) + deflate_state *s; +{ + register unsigned n, m; + register Posf *p; + unsigned more; /* Amount of free space at the end of the window. */ + uInt wsize = s->w_size; + + do { + more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart); + + /* Deal with !@#$% 64K limit: */ + if (more == 0 && s->strstart == 0 && s->lookahead == 0) { + more = wsize; + } else if (more == (unsigned)(-1)) { + /* Very unlikely, but possible on 16 bit machine if strstart == 0 + * and lookahead == 1 (input done one byte at time) + */ + more--; + + /* If the window is almost full and there is insufficient lookahead, + * move the upper half to the lower one to make room in the upper half. + */ + } else if (s->strstart >= wsize+MAX_DIST(s)) { + + /* By the IN assertion, the window is not empty so we can't confuse + * more == 0 with more == 64K on a 16 bit machine. + */ + zmemcpy((charf *)s->window, (charf *)s->window+wsize, + (unsigned)wsize); + s->match_start -= wsize; + s->strstart -= wsize; /* we now have strstart >= MAX_DIST */ + + s->block_start -= (long) wsize; + + /* Slide the hash table (could be avoided with 32 bit values + at the expense of memory usage): + */ + n = s->hash_size; + p = &s->head[n]; + do { + m = *--p; + *p = (Pos)(m >= wsize ? m-wsize : NIL); + } while (--n); + + n = wsize; + p = &s->prev[n]; + do { + m = *--p; + *p = (Pos)(m >= wsize ? m-wsize : NIL); + /* If n is not on any hash chain, prev[n] is garbage but + * its value will never be used. + */ + } while (--n); + + more += wsize; + } + if (s->strm->avail_in == 0) return; + + /* If there was no sliding: + * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 && + * more == window_size - lookahead - strstart + * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1) + * => more >= window_size - 2*WSIZE + 2 + * In the BIG_MEM or MMAP case (not yet supported), + * window_size == input_size + MIN_LOOKAHEAD && + * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD. + * Otherwise, window_size == 2*WSIZE so more >= 2. + * If there was sliding, more >= WSIZE. So in all cases, more >= 2. + */ + Assert(more >= 2, "more < 2"); + + n = read_buf(s->strm, (charf *)s->window + s->strstart + s->lookahead, + more); + s->lookahead += n; + + /* Initialize the hash value now that we have some input: */ + if (s->lookahead >= MIN_MATCH) { + s->ins_h = s->window[s->strstart]; + UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]); +#if MIN_MATCH != 3 + Call UPDATE_HASH() MIN_MATCH-3 more times +#endif + } + /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage, + * but this is not important since only literal bytes will be emitted. + */ + + } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0); +} + +/* =========================================================================== + * Flush the current block, with given end-of-file flag. + * IN assertion: strstart is set to the end of the current match. + */ +#define FLUSH_BLOCK_ONLY(s, flush) { \ + ct_flush_block(s, (s->block_start >= 0L ? \ + (charf *)&s->window[(unsigned)s->block_start] : \ + (charf *)Z_NULL), (long)s->strstart - s->block_start, (flush)); \ + s->block_start = s->strstart; \ + flush_pending(s->strm); \ + Tracev((stderr,"[FLUSH]")); \ +} + +/* Same but force premature exit if necessary. */ +#define FLUSH_BLOCK(s, flush) { \ + FLUSH_BLOCK_ONLY(s, flush); \ + if (s->strm->avail_out == 0) return 1; \ +} + +/* =========================================================================== + * Compress as much as possible from the input stream, return true if + * processing was terminated prematurely (no more input or output space). + * This function does not perform lazy evaluationof matches and inserts + * new strings in the dictionary only for unmatched strings or for short + * matches. It is used only for the fast compression options. + */ +local int deflate_fast(s, flush) + deflate_state *s; + int flush; +{ + IPos hash_head = NIL; /* head of the hash chain */ + int bflush; /* set if current block must be flushed */ + + s->prev_length = MIN_MATCH-1; + + for (;;) { + /* Make sure that we always have enough lookahead, except + * at the end of the input file. We need MAX_MATCH bytes + * for the next match, plus MIN_MATCH bytes to insert the + * string following the next match. + */ + if (s->lookahead < MIN_LOOKAHEAD) { + fill_window(s); + if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) return 1; + + if (s->lookahead == 0) break; /* flush the current block */ + } + + /* Insert the string window[strstart .. strstart+2] in the + * dictionary, and set hash_head to the head of the hash chain: + */ + if (s->lookahead >= MIN_MATCH) { + INSERT_STRING(s, s->strstart, hash_head); + } + + /* Find the longest match, discarding those <= prev_length. + * At this point we have always match_length < MIN_MATCH + */ + if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) { + /* To simplify the code, we prevent matches with the string + * of window index 0 (in particular we have to avoid a match + * of the string with itself at the start of the input file). + */ + if (s->strategy != Z_HUFFMAN_ONLY) { + s->match_length = longest_match (s, hash_head); + } + /* longest_match() sets match_start */ + + if (s->match_length > s->lookahead) s->match_length = s->lookahead; + } + if (s->match_length >= MIN_MATCH) { + check_match(s, s->strstart, s->match_start, s->match_length); + + bflush = ct_tally(s, s->strstart - s->match_start, + s->match_length - MIN_MATCH); + + s->lookahead -= s->match_length; + + /* Insert new strings in the hash table only if the match length + * is not too large. This saves time but degrades compression. + */ + if (s->match_length <= s->max_insert_length && + s->lookahead >= MIN_MATCH) { + s->match_length--; /* string at strstart already in hash table */ + do { + s->strstart++; + INSERT_STRING(s, s->strstart, hash_head); + /* strstart never exceeds WSIZE-MAX_MATCH, so there are + * always MIN_MATCH bytes ahead. + */ + } while (--s->match_length != 0); + s->strstart++; + } else { + s->strstart += s->match_length; + s->match_length = 0; + s->ins_h = s->window[s->strstart]; + UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]); +#if MIN_MATCH != 3 + Call UPDATE_HASH() MIN_MATCH-3 more times +#endif + /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not + * matter since it will be recomputed at next deflate call. + */ + } + } else { + /* No match, output a literal byte */ + Tracevv((stderr,"%c", s->window[s->strstart])); + bflush = ct_tally (s, 0, s->window[s->strstart]); + s->lookahead--; + s->strstart++; + } + if (bflush) FLUSH_BLOCK(s, Z_NO_FLUSH); + } + FLUSH_BLOCK(s, flush); + return 0; /* normal exit */ +} + +/* =========================================================================== + * Same as above, but achieves better compression. We use a lazy + * evaluation for matches: a match is finally adopted only if there is + * no better match at the next window position. + */ +local int deflate_slow(s, flush) + deflate_state *s; + int flush; +{ + IPos hash_head = NIL; /* head of hash chain */ + int bflush; /* set if current block must be flushed */ + + /* Process the input block. */ + for (;;) { + /* Make sure that we always have enough lookahead, except + * at the end of the input file. We need MAX_MATCH bytes + * for the next match, plus MIN_MATCH bytes to insert the + * string following the next match. + */ + if (s->lookahead < MIN_LOOKAHEAD) { + fill_window(s); + if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) return 1; + + if (s->lookahead == 0) break; /* flush the current block */ + } + + /* Insert the string window[strstart .. strstart+2] in the + * dictionary, and set hash_head to the head of the hash chain: + */ + if (s->lookahead >= MIN_MATCH) { + INSERT_STRING(s, s->strstart, hash_head); + } + + /* Find the longest match, discarding those <= prev_length. + */ + s->prev_length = s->match_length, s->prev_match = s->match_start; + s->match_length = MIN_MATCH-1; + + if (hash_head != NIL && s->prev_length < s->max_lazy_match && + s->strstart - hash_head <= MAX_DIST(s)) { + /* To simplify the code, we prevent matches with the string + * of window index 0 (in particular we have to avoid a match + * of the string with itself at the start of the input file). + */ + if (s->strategy != Z_HUFFMAN_ONLY) { + s->match_length = longest_match (s, hash_head); + } + /* longest_match() sets match_start */ + if (s->match_length > s->lookahead) s->match_length = s->lookahead; + + if (s->match_length <= 5 && (s->strategy == Z_FILTERED || + (s->match_length == MIN_MATCH && + s->strstart - s->match_start > TOO_FAR))) { + + /* If prev_match is also MIN_MATCH, match_start is garbage + * but we will ignore the current match anyway. + */ + s->match_length = MIN_MATCH-1; + } + } + /* If there was a match at the previous step and the current + * match is not better, output the previous match: + */ + if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) { + uInt max_insert = s->strstart + s->lookahead - MIN_MATCH; + /* Do not insert strings in hash table beyond this. */ + + check_match(s, s->strstart-1, s->prev_match, s->prev_length); + + bflush = ct_tally(s, s->strstart -1 - s->prev_match, + s->prev_length - MIN_MATCH); + + /* Insert in hash table all strings up to the end of the match. + * strstart-1 and strstart are already inserted. If there is not + * enough lookahead, the last two strings are not inserted in + * the hash table. + */ + s->lookahead -= s->prev_length-1; + s->prev_length -= 2; + do { + if (++s->strstart <= max_insert) { + INSERT_STRING(s, s->strstart, hash_head); + } + } while (--s->prev_length != 0); + s->match_available = 0; + s->match_length = MIN_MATCH-1; + s->strstart++; + + if (bflush) FLUSH_BLOCK(s, Z_NO_FLUSH); + + } else if (s->match_available) { + /* If there was no match at the previous position, output a + * single literal. If there was a match but the current match + * is longer, truncate the previous match to a single literal. + */ + Tracevv((stderr,"%c", s->window[s->strstart-1])); + if (ct_tally (s, 0, s->window[s->strstart-1])) { + FLUSH_BLOCK_ONLY(s, Z_NO_FLUSH); + } + s->strstart++; + s->lookahead--; + if (s->strm->avail_out == 0) return 1; + } else { + /* There is no previous match to compare with, wait for + * the next step to decide. + */ + s->match_available = 1; + s->strstart++; + s->lookahead--; + } + } + Assert (flush != Z_NO_FLUSH, "no flush?"); + if (s->match_available) { + Tracevv((stderr,"%c", s->window[s->strstart-1])); + ct_tally (s, 0, s->window[s->strstart-1]); + s->match_available = 0; + } + FLUSH_BLOCK(s, flush); + return 0; +} + + +/*+++++*/ +/* trees.c -- output deflated data using Huffman coding + * Copyright (C) 1995 Jean-loup Gailly + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* + * ALGORITHM + * + * The "deflation" process uses several Huffman trees. The more + * common source values are represented by shorter bit sequences. + * + * Each code tree is stored in a compressed form which is itself + * a Huffman encoding of the lengths of all the code strings (in + * ascending order by source values). The actual code strings are + * reconstructed from the lengths in the inflate process, as described + * in the deflate specification. + * + * REFERENCES + * + * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification". + * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc + * + * Storer, James A. + * Data Compression: Methods and Theory, pp. 49-50. + * Computer Science Press, 1988. ISBN 0-7167-8156-5. + * + * Sedgewick, R. + * Algorithms, p290. + * Addison-Wesley, 1983. ISBN 0-201-06672-6. + */ + +/* From: trees.c,v 1.5 1995/05/03 17:27:12 jloup Exp */ + +#ifdef DEBUG_ZLIB +# include <ctype.h> +#endif + +/* =========================================================================== + * Constants + */ + +#define MAX_BL_BITS 7 +/* Bit length codes must not exceed MAX_BL_BITS bits */ + +#define END_BLOCK 256 +/* end of block literal code */ + +#define REP_3_6 16 +/* repeat previous bit length 3-6 times (2 bits of repeat count) */ + +#define REPZ_3_10 17 +/* repeat a zero length 3-10 times (3 bits of repeat count) */ + +#define REPZ_11_138 18 +/* repeat a zero length 11-138 times (7 bits of repeat count) */ + +local int extra_lbits[LENGTH_CODES] /* extra bits for each length code */ + = {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}; + +local int extra_dbits[D_CODES] /* extra bits for each distance code */ + = {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}; + +local int extra_blbits[BL_CODES]/* extra bits for each bit length code */ + = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7}; + +local uch bl_order[BL_CODES] + = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15}; +/* The lengths of the bit length codes are sent in order of decreasing + * probability, to avoid transmitting the lengths for unused bit length codes. + */ + +#define Buf_size (8 * 2*sizeof(char)) +/* Number of bits used within bi_buf. (bi_buf might be implemented on + * more than 16 bits on some systems.) + */ + +/* =========================================================================== + * Local data. These are initialized only once. + * To do: initialize at compile time to be completely reentrant. ??? + */ + +local ct_data static_ltree[L_CODES+2]; +/* The static literal tree. Since the bit lengths are imposed, there is no + * need for the L_CODES extra codes used during heap construction. However + * The codes 286 and 287 are needed to build a canonical tree (see ct_init + * below). + */ + +local ct_data static_dtree[D_CODES]; +/* The static distance tree. (Actually a trivial tree since all codes use + * 5 bits.) + */ + +local uch dist_code[512]; +/* distance codes. The first 256 values correspond to the distances + * 3 .. 258, the last 256 values correspond to the top 8 bits of + * the 15 bit distances. + */ + +local uch length_code[MAX_MATCH-MIN_MATCH+1]; +/* length code for each normalized match length (0 == MIN_MATCH) */ + +local int base_length[LENGTH_CODES]; +/* First normalized length for each code (0 = MIN_MATCH) */ + +local int base_dist[D_CODES]; +/* First normalized distance for each code (0 = distance of 1) */ + +struct static_tree_desc_s { + ct_data *static_tree; /* static tree or NULL */ + intf *extra_bits; /* extra bits for each code or NULL */ + int extra_base; /* base index for extra_bits */ + int elems; /* max number of elements in the tree */ + int max_length; /* max bit length for the codes */ +}; + +local static_tree_desc static_l_desc = +{static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS}; + +local static_tree_desc static_d_desc = +{static_dtree, extra_dbits, 0, D_CODES, MAX_BITS}; + +local static_tree_desc static_bl_desc = +{(ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS}; + +/* =========================================================================== + * Local (static) routines in this file. + */ + +local void ct_static_init OF((void)); +local void init_block OF((deflate_state *s)); +local void pqdownheap OF((deflate_state *s, ct_data *tree, int k)); +local void gen_bitlen OF((deflate_state *s, tree_desc *desc)); +local void gen_codes OF((ct_data *tree, int max_code, ushf *bl_count)); +local void build_tree OF((deflate_state *s, tree_desc *desc)); +local void scan_tree OF((deflate_state *s, ct_data *tree, int max_code)); +local void send_tree OF((deflate_state *s, ct_data *tree, int max_code)); +local int build_bl_tree OF((deflate_state *s)); +local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes, + int blcodes)); +local void compress_block OF((deflate_state *s, ct_data *ltree, + ct_data *dtree)); +local void set_data_type OF((deflate_state *s)); +local unsigned bi_reverse OF((unsigned value, int length)); +local void bi_windup OF((deflate_state *s)); +local void bi_flush OF((deflate_state *s)); +local void copy_block OF((deflate_state *s, charf *buf, unsigned len, + int header)); + +#ifndef DEBUG_ZLIB +# define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len) + /* Send a code of the given tree. c and tree must not have side effects */ + +#else /* DEBUG_ZLIB */ +# define send_code(s, c, tree) \ + { if (verbose>1) fprintf(stderr,"\ncd %3d ",(c)); \ + send_bits(s, tree[c].Code, tree[c].Len); } +#endif + +#define d_code(dist) \ + ((dist) < 256 ? dist_code[dist] : dist_code[256+((dist)>>7)]) +/* Mapping from a distance to a distance code. dist is the distance - 1 and + * must not have side effects. dist_code[256] and dist_code[257] are never + * used. + */ + +/* =========================================================================== + * Output a short LSB first on the stream. + * IN assertion: there is enough room in pendingBuf. + */ +#define put_short(s, w) { \ + put_byte(s, (uch)((w) & 0xff)); \ + put_byte(s, (uch)((ush)(w) >> 8)); \ +} + +/* =========================================================================== + * Send a value on a given number of bits. + * IN assertion: length <= 16 and value fits in length bits. + */ +#ifdef DEBUG_ZLIB +local void send_bits OF((deflate_state *s, int value, int length)); + +local void send_bits(s, value, length) + deflate_state *s; + int value; /* value to send */ + int length; /* number of bits */ +{ + Tracev((stderr," l %2d v %4x ", length, value)); + Assert(length > 0 && length <= 15, "invalid length"); + s->bits_sent += (ulg)length; + + /* If not enough room in bi_buf, use (valid) bits from bi_buf and + * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid)) + * unused bits in value. + */ + if (s->bi_valid > (int)Buf_size - length) { + s->bi_buf |= (value << s->bi_valid); + put_short(s, s->bi_buf); + s->bi_buf = (ush)value >> (Buf_size - s->bi_valid); + s->bi_valid += length - Buf_size; + } else { + s->bi_buf |= value << s->bi_valid; + s->bi_valid += length; + } +} +#else /* !DEBUG_ZLIB */ + +#define send_bits(s, value, length) \ +{ int len = length;\ + if (s->bi_valid > (int)Buf_size - len) {\ + int val = value;\ + s->bi_buf |= (val << s->bi_valid);\ + put_short(s, s->bi_buf);\ + s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\ + s->bi_valid += len - Buf_size;\ + } else {\ + s->bi_buf |= (value) << s->bi_valid;\ + s->bi_valid += len;\ + }\ +} +#endif /* DEBUG_ZLIB */ + + +#define MAX(a,b) (a >= b ? a : b) +/* the arguments must not have side effects */ + +/* =========================================================================== + * Initialize the various 'constant' tables. + * To do: do this at compile time. + */ +local void ct_static_init() +{ + int n; /* iterates over tree elements */ + int bits; /* bit counter */ + int length; /* length value */ + int code; /* code value */ + int dist; /* distance index */ + ush bl_count[MAX_BITS+1]; + /* number of codes at each bit length for an optimal tree */ + + /* Initialize the mapping length (0..255) -> length code (0..28) */ + length = 0; + for (code = 0; code < LENGTH_CODES-1; code++) { + base_length[code] = length; + for (n = 0; n < (1<<extra_lbits[code]); n++) { + length_code[length++] = (uch)code; + } + } + Assert (length == 256, "ct_static_init: length != 256"); + /* Note that the length 255 (match length 258) can be represented + * in two different ways: code 284 + 5 bits or code 285, so we + * overwrite length_code[255] to use the best encoding: + */ + length_code[length-1] = (uch)code; + + /* Initialize the mapping dist (0..32K) -> dist code (0..29) */ + dist = 0; + for (code = 0 ; code < 16; code++) { + base_dist[code] = dist; + for (n = 0; n < (1<<extra_dbits[code]); n++) { + dist_code[dist++] = (uch)code; + } + } + Assert (dist == 256, "ct_static_init: dist != 256"); + dist >>= 7; /* from now on, all distances are divided by 128 */ + for ( ; code < D_CODES; code++) { + base_dist[code] = dist << 7; + for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) { + dist_code[256 + dist++] = (uch)code; + } + } + Assert (dist == 256, "ct_static_init: 256+dist != 512"); + + /* Construct the codes of the static literal tree */ + for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0; + n = 0; + while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++; + while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++; + while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++; + while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++; + /* Codes 286 and 287 do not exist, but we must include them in the + * tree construction to get a canonical Huffman tree (longest code + * all ones) + */ + gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count); + + /* The static distance tree is trivial: */ + for (n = 0; n < D_CODES; n++) { + static_dtree[n].Len = 5; + static_dtree[n].Code = bi_reverse(n, 5); + } +} + +/* =========================================================================== + * Initialize the tree data structures for a new zlib stream. + */ +local void ct_init(s) + deflate_state *s; +{ + if (static_dtree[0].Len == 0) { + ct_static_init(); /* To do: at compile time */ + } + + s->compressed_len = 0L; + + s->l_desc.dyn_tree = s->dyn_ltree; + s->l_desc.stat_desc = &static_l_desc; + + s->d_desc.dyn_tree = s->dyn_dtree; + s->d_desc.stat_desc = &static_d_desc; + + s->bl_desc.dyn_tree = s->bl_tree; + s->bl_desc.stat_desc = &static_bl_desc; + + s->bi_buf = 0; + s->bi_valid = 0; + s->last_eob_len = 8; /* enough lookahead for inflate */ +#ifdef DEBUG_ZLIB + s->bits_sent = 0L; +#endif + s->blocks_in_packet = 0; + + /* Initialize the first block of the first file: */ + init_block(s); +} + +/* =========================================================================== + * Initialize a new block. + */ +local void init_block(s) + deflate_state *s; +{ + int n; /* iterates over tree elements */ + + /* Initialize the trees. */ + for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0; + for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0; + for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0; + + s->dyn_ltree[END_BLOCK].Freq = 1; + s->opt_len = s->static_len = 0L; + s->last_lit = s->matches = 0; +} + +#define SMALLEST 1 +/* Index within the heap array of least frequent node in the Huffman tree */ + + +/* =========================================================================== + * Remove the smallest element from the heap and recreate the heap with + * one less element. Updates heap and heap_len. + */ +#define pqremove(s, tree, top) \ +{\ + top = s->heap[SMALLEST]; \ + s->heap[SMALLEST] = s->heap[s->heap_len--]; \ + pqdownheap(s, tree, SMALLEST); \ +} + +/* =========================================================================== + * Compares to subtrees, using the tree depth as tie breaker when + * the subtrees have equal frequency. This minimizes the worst case length. + */ +#define smaller(tree, n, m, depth) \ + (tree[n].Freq < tree[m].Freq || \ + (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m])) + +/* =========================================================================== + * Restore the heap property by moving down the tree starting at node k, + * exchanging a node with the smallest of its two sons if necessary, stopping + * when the heap property is re-established (each father smaller than its + * two sons). + */ +local void pqdownheap(s, tree, k) + deflate_state *s; + ct_data *tree; /* the tree to restore */ + int k; /* node to move down */ +{ + int v = s->heap[k]; + int j = k << 1; /* left son of k */ + while (j <= s->heap_len) { + /* Set j to the smallest of the two sons: */ + if (j < s->heap_len && + smaller(tree, s->heap[j+1], s->heap[j], s->depth)) { + j++; + } + /* Exit if v is smaller than both sons */ + if (smaller(tree, v, s->heap[j], s->depth)) break; + + /* Exchange v with the smallest son */ + s->heap[k] = s->heap[j]; k = j; + + /* And continue down the tree, setting j to the left son of k */ + j <<= 1; + } + s->heap[k] = v; +} + +/* =========================================================================== + * Compute the optimal bit lengths for a tree and update the total bit length + * for the current block. + * IN assertion: the fields freq and dad are set, heap[heap_max] and + * above are the tree nodes sorted by increasing frequency. + * OUT assertions: the field len is set to the optimal bit length, the + * array bl_count contains the frequencies for each bit length. + * The length opt_len is updated; static_len is also updated if stree is + * not null. + */ +local void gen_bitlen(s, desc) + deflate_state *s; + tree_desc *desc; /* the tree descriptor */ +{ + ct_data *tree = desc->dyn_tree; + int max_code = desc->max_code; + ct_data *stree = desc->stat_desc->static_tree; + intf *extra = desc->stat_desc->extra_bits; + int base = desc->stat_desc->extra_base; + int max_length = desc->stat_desc->max_length; + int h; /* heap index */ + int n, m; /* iterate over the tree elements */ + int bits; /* bit length */ + int xbits; /* extra bits */ + ush f; /* frequency */ + int overflow = 0; /* number of elements with bit length too large */ + + for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0; + + /* In a first pass, compute the optimal bit lengths (which may + * overflow in the case of the bit length tree). + */ + tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */ + + for (h = s->heap_max+1; h < HEAP_SIZE; h++) { + n = s->heap[h]; + bits = tree[tree[n].Dad].Len + 1; + if (bits > max_length) bits = max_length, overflow++; + tree[n].Len = (ush)bits; + /* We overwrite tree[n].Dad which is no longer needed */ + + if (n > max_code) continue; /* not a leaf node */ + + s->bl_count[bits]++; + xbits = 0; + if (n >= base) xbits = extra[n-base]; + f = tree[n].Freq; + s->opt_len += (ulg)f * (bits + xbits); + if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits); + } + if (overflow == 0) return; + + Trace((stderr,"\nbit length overflow\n")); + /* This happens for example on obj2 and pic of the Calgary corpus */ + + /* Find the first bit length which could increase: */ + do { + bits = max_length-1; + while (s->bl_count[bits] == 0) bits--; + s->bl_count[bits]--; /* move one leaf down the tree */ + s->bl_count[bits+1] += 2; /* move one overflow item as its brother */ + s->bl_count[max_length]--; + /* The brother of the overflow item also moves one step up, + * but this does not affect bl_count[max_length] + */ + overflow -= 2; + } while (overflow > 0); + + /* Now recompute all bit lengths, scanning in increasing frequency. + * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all + * lengths instead of fixing only the wrong ones. This idea is taken + * from 'ar' written by Haruhiko Okumura.) + */ + for (bits = max_length; bits != 0; bits--) { + n = s->bl_count[bits]; + while (n != 0) { + m = s->heap[--h]; + if (m > max_code) continue; + if (tree[m].Len != (unsigned) bits) { + Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits)); + s->opt_len += ((long)bits - (long)tree[m].Len) + *(long)tree[m].Freq; + tree[m].Len = (ush)bits; + } + n--; + } + } +} + +/* =========================================================================== + * Generate the codes for a given tree and bit counts (which need not be + * optimal). + * IN assertion: the array bl_count contains the bit length statistics for + * the given tree and the field len is set for all tree elements. + * OUT assertion: the field code is set for all tree elements of non + * zero code length. + */ +local void gen_codes (tree, max_code, bl_count) + ct_data *tree; /* the tree to decorate */ + int max_code; /* largest code with non zero frequency */ + ushf *bl_count; /* number of codes at each bit length */ +{ + ush next_code[MAX_BITS+1]; /* next code value for each bit length */ + ush code = 0; /* running code value */ + int bits; /* bit index */ + int n; /* code index */ + + /* The distribution counts are first used to generate the code values + * without bit reversal. + */ + for (bits = 1; bits <= MAX_BITS; bits++) { + next_code[bits] = code = (code + bl_count[bits-1]) << 1; + } + /* Check that the bit counts in bl_count are consistent. The last code + * must be all ones. + */ + Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1, + "inconsistent bit counts"); + Tracev((stderr,"\ngen_codes: max_code %d ", max_code)); + + for (n = 0; n <= max_code; n++) { + int len = tree[n].Len; + if (len == 0) continue; + /* Now reverse the bits */ + tree[n].Code = bi_reverse(next_code[len]++, len); + + Tracec(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ", + n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1)); + } +} + +/* =========================================================================== + * Construct one Huffman tree and assigns the code bit strings and lengths. + * Update the total bit length for the current block. + * IN assertion: the field freq is set for all tree elements. + * OUT assertions: the fields len and code are set to the optimal bit length + * and corresponding code. The length opt_len is updated; static_len is + * also updated if stree is not null. The field max_code is set. + */ +local void build_tree(s, desc) + deflate_state *s; + tree_desc *desc; /* the tree descriptor */ +{ + ct_data *tree = desc->dyn_tree; + ct_data *stree = desc->stat_desc->static_tree; + int elems = desc->stat_desc->elems; + int n, m; /* iterate over heap elements */ + int max_code = -1; /* largest code with non zero frequency */ + int node; /* new node being created */ + + /* Construct the initial heap, with least frequent element in + * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1]. + * heap[0] is not used. + */ + s->heap_len = 0, s->heap_max = HEAP_SIZE; + + for (n = 0; n < elems; n++) { + if (tree[n].Freq != 0) { + s->heap[++(s->heap_len)] = max_code = n; + s->depth[n] = 0; + } else { + tree[n].Len = 0; + } + } + + /* The pkzip format requires that at least one distance code exists, + * and that at least one bit should be sent even if there is only one + * possible code. So to avoid special checks later on we force at least + * two codes of non zero frequency. + */ + while (s->heap_len < 2) { + node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0); + tree[node].Freq = 1; + s->depth[node] = 0; + s->opt_len--; if (stree) s->static_len -= stree[node].Len; + /* node is 0 or 1 so it does not have extra bits */ + } + desc->max_code = max_code; + + /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree, + * establish sub-heaps of increasing lengths: + */ + for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n); + + /* Construct the Huffman tree by repeatedly combining the least two + * frequent nodes. + */ + node = elems; /* next internal node of the tree */ + do { + pqremove(s, tree, n); /* n = node of least frequency */ + m = s->heap[SMALLEST]; /* m = node of next least frequency */ + + s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */ + s->heap[--(s->heap_max)] = m; + + /* Create a new node father of n and m */ + tree[node].Freq = tree[n].Freq + tree[m].Freq; + s->depth[node] = (uch) (MAX(s->depth[n], s->depth[m]) + 1); + tree[n].Dad = tree[m].Dad = (ush)node; +#ifdef DUMP_BL_TREE + if (tree == s->bl_tree) { + fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)", + node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq); + } +#endif + /* and insert the new node in the heap */ + s->heap[SMALLEST] = node++; + pqdownheap(s, tree, SMALLEST); + + } while (s->heap_len >= 2); + + s->heap[--(s->heap_max)] = s->heap[SMALLEST]; + + /* At this point, the fields freq and dad are set. We can now + * generate the bit lengths. + */ + gen_bitlen(s, (tree_desc *)desc); + + /* The field len is now set, we can generate the bit codes */ + gen_codes ((ct_data *)tree, max_code, s->bl_count); +} + +/* =========================================================================== + * Scan a literal or distance tree to determine the frequencies of the codes + * in the bit length tree. + */ +local void scan_tree (s, tree, max_code) + deflate_state *s; + ct_data *tree; /* the tree to be scanned */ + int max_code; /* and its largest code of non zero frequency */ +{ + int n; /* iterates over all tree elements */ + int prevlen = -1; /* last emitted length */ + int curlen; /* length of current code */ + int nextlen = tree[0].Len; /* length of next code */ + int count = 0; /* repeat count of the current code */ + int max_count = 7; /* max repeat count */ + int min_count = 4; /* min repeat count */ + + if (nextlen == 0) max_count = 138, min_count = 3; + tree[max_code+1].Len = (ush)0xffff; /* guard */ + + for (n = 0; n <= max_code; n++) { + curlen = nextlen; nextlen = tree[n+1].Len; + if (++count < max_count && curlen == nextlen) { + continue; + } else if (count < min_count) { + s->bl_tree[curlen].Freq += count; + } else if (curlen != 0) { + if (curlen != prevlen) s->bl_tree[curlen].Freq++; + s->bl_tree[REP_3_6].Freq++; + } else if (count <= 10) { + s->bl_tree[REPZ_3_10].Freq++; + } else { + s->bl_tree[REPZ_11_138].Freq++; + } + count = 0; prevlen = curlen; + if (nextlen == 0) { + max_count = 138, min_count = 3; + } else if (curlen == nextlen) { + max_count = 6, min_count = 3; + } else { + max_count = 7, min_count = 4; + } + } +} + +/* =========================================================================== + * Send a literal or distance tree in compressed form, using the codes in + * bl_tree. + */ +local void send_tree (s, tree, max_code) + deflate_state *s; + ct_data *tree; /* the tree to be scanned */ + int max_code; /* and its largest code of non zero frequency */ +{ + int n; /* iterates over all tree elements */ + int prevlen = -1; /* last emitted length */ + int curlen; /* length of current code */ + int nextlen = tree[0].Len; /* length of next code */ + int count = 0; /* repeat count of the current code */ + int max_count = 7; /* max repeat count */ + int min_count = 4; /* min repeat count */ + + /* tree[max_code+1].Len = -1; */ /* guard already set */ + if (nextlen == 0) max_count = 138, min_count = 3; + + for (n = 0; n <= max_code; n++) { + curlen = nextlen; nextlen = tree[n+1].Len; + if (++count < max_count && curlen == nextlen) { + continue; + } else if (count < min_count) { + do { send_code(s, curlen, s->bl_tree); } while (--count != 0); + + } else if (curlen != 0) { + if (curlen != prevlen) { + send_code(s, curlen, s->bl_tree); count--; + } + Assert(count >= 3 && count <= 6, " 3_6?"); + send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2); + + } else if (count <= 10) { + send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3); + + } else { + send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7); + } + count = 0; prevlen = curlen; + if (nextlen == 0) { + max_count = 138, min_count = 3; + } else if (curlen == nextlen) { + max_count = 6, min_count = 3; + } else { + max_count = 7, min_count = 4; + } + } +} + +/* =========================================================================== + * Construct the Huffman tree for the bit lengths and return the index in + * bl_order of the last bit length code to send. + */ +local int build_bl_tree(s) + deflate_state *s; +{ + int max_blindex; /* index of last bit length code of non zero freq */ + + /* Determine the bit length frequencies for literal and distance trees */ + scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code); + scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code); + + /* Build the bit length tree: */ + build_tree(s, (tree_desc *)(&(s->bl_desc))); + /* opt_len now includes the length of the tree representations, except + * the lengths of the bit lengths codes and the 5+5+4 bits for the counts. + */ + + /* Determine the number of bit length codes to send. The pkzip format + * requires that at least 4 bit length codes be sent. (appnote.txt says + * 3 but the actual value used is 4.) + */ + for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) { + if (s->bl_tree[bl_order[max_blindex]].Len != 0) break; + } + /* Update opt_len to include the bit length tree and counts */ + s->opt_len += 3*(max_blindex+1) + 5+5+4; + Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld", + s->opt_len, s->static_len)); + + return max_blindex; +} + +/* =========================================================================== + * Send the header for a block using dynamic Huffman trees: the counts, the + * lengths of the bit length codes, the literal tree and the distance tree. + * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4. + */ +local void send_all_trees(s, lcodes, dcodes, blcodes) + deflate_state *s; + int lcodes, dcodes, blcodes; /* number of codes for each tree */ +{ + int rank; /* index in bl_order */ + + Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes"); + Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES, + "too many codes"); + Tracev((stderr, "\nbl counts: ")); + send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */ + send_bits(s, dcodes-1, 5); + send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */ + for (rank = 0; rank < blcodes; rank++) { + Tracev((stderr, "\nbl code %2d ", bl_order[rank])); + send_bits(s, s->bl_tree[bl_order[rank]].Len, 3); + } + Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent)); + + send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */ + Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent)); + + send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */ + Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent)); +} + +/* =========================================================================== + * Send a stored block + */ +local void ct_stored_block(s, buf, stored_len, eof) + deflate_state *s; + charf *buf; /* input block */ + ulg stored_len; /* length of input block */ + int eof; /* true if this is the last block for a file */ +{ + send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */ + s->compressed_len = (s->compressed_len + 3 + 7) & ~7L; + s->compressed_len += (stored_len + 4) << 3; + + copy_block(s, buf, (unsigned)stored_len, 1); /* with header */ +} + +/* Send just the `stored block' type code without any length bytes or data. + */ +local void ct_stored_type_only(s) + deflate_state *s; +{ + send_bits(s, (STORED_BLOCK << 1), 3); + bi_windup(s); + s->compressed_len = (s->compressed_len + 3) & ~7L; +} + + +/* =========================================================================== + * Send one empty static block to give enough lookahead for inflate. + * This takes 10 bits, of which 7 may remain in the bit buffer. + * The current inflate code requires 9 bits of lookahead. If the EOB + * code for the previous block was coded on 5 bits or less, inflate + * may have only 5+3 bits of lookahead to decode this EOB. + * (There are no problems if the previous block is stored or fixed.) + */ +local void ct_align(s) + deflate_state *s; +{ + send_bits(s, STATIC_TREES<<1, 3); + send_code(s, END_BLOCK, static_ltree); + s->compressed_len += 10L; /* 3 for block type, 7 for EOB */ + bi_flush(s); + /* Of the 10 bits for the empty block, we have already sent + * (10 - bi_valid) bits. The lookahead for the EOB of the previous + * block was thus its length plus what we have just sent. + */ + if (s->last_eob_len + 10 - s->bi_valid < 9) { + send_bits(s, STATIC_TREES<<1, 3); + send_code(s, END_BLOCK, static_ltree); + s->compressed_len += 10L; + bi_flush(s); + } + s->last_eob_len = 7; +} + +/* =========================================================================== + * Determine the best encoding for the current block: dynamic trees, static + * trees or store, and output the encoded block to the zip file. This function + * returns the total compressed length for the file so far. + */ +local ulg ct_flush_block(s, buf, stored_len, flush) + deflate_state *s; + charf *buf; /* input block, or NULL if too old */ + ulg stored_len; /* length of input block */ + int flush; /* Z_FINISH if this is the last block for a file */ +{ + ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */ + int max_blindex; /* index of last bit length code of non zero freq */ + int eof = flush == Z_FINISH; + + ++s->blocks_in_packet; + + /* Check if the file is ascii or binary */ + if (s->data_type == UNKNOWN) set_data_type(s); + + /* Construct the literal and distance trees */ + build_tree(s, (tree_desc *)(&(s->l_desc))); + Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len, + s->static_len)); + + build_tree(s, (tree_desc *)(&(s->d_desc))); + Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len, + s->static_len)); + /* At this point, opt_len and static_len are the total bit lengths of + * the compressed block data, excluding the tree representations. + */ + + /* Build the bit length tree for the above two trees, and get the index + * in bl_order of the last bit length code to send. + */ + max_blindex = build_bl_tree(s); + + /* Determine the best encoding. Compute first the block length in bytes */ + opt_lenb = (s->opt_len+3+7)>>3; + static_lenb = (s->static_len+3+7)>>3; + + Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ", + opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len, + s->last_lit)); + + if (static_lenb <= opt_lenb) opt_lenb = static_lenb; + + /* If compression failed and this is the first and last block, + * and if the .zip file can be seeked (to rewrite the local header), + * the whole file is transformed into a stored file: + */ +#ifdef STORED_FILE_OK +# ifdef FORCE_STORED_FILE + if (eof && compressed_len == 0L) /* force stored file */ +# else + if (stored_len <= opt_lenb && eof && s->compressed_len==0L && seekable()) +# endif + { + /* Since LIT_BUFSIZE <= 2*WSIZE, the input data must be there: */ + if (buf == (charf*)0) error ("block vanished"); + + copy_block(buf, (unsigned)stored_len, 0); /* without header */ + s->compressed_len = stored_len << 3; + s->method = STORED; + } else +#endif /* STORED_FILE_OK */ + + /* For Z_PACKET_FLUSH, if we don't achieve the required minimum + * compression, and this block contains all the data since the last + * time we used Z_PACKET_FLUSH, then just omit this block completely + * from the output. + */ + if (flush == Z_PACKET_FLUSH && s->blocks_in_packet == 1 + && opt_lenb > stored_len - s->minCompr) { + s->blocks_in_packet = 0; + /* output nothing */ + } else + +#ifdef FORCE_STORED + if (buf != (char*)0) /* force stored block */ +#else + if (stored_len+4 <= opt_lenb && buf != (char*)0) + /* 4: two words for the lengths */ +#endif + { + /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE. + * Otherwise we can't have processed more than WSIZE input bytes since + * the last block flush, because compression would have been + * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to + * transform a block into a stored block. + */ + ct_stored_block(s, buf, stored_len, eof); + } else + +#ifdef FORCE_STATIC + if (static_lenb >= 0) /* force static trees */ +#else + if (static_lenb == opt_lenb) +#endif + { + send_bits(s, (STATIC_TREES<<1)+eof, 3); + compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree); + s->compressed_len += 3 + s->static_len; + } else { + send_bits(s, (DYN_TREES<<1)+eof, 3); + send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1, + max_blindex+1); + compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree); + s->compressed_len += 3 + s->opt_len; + } + Assert (s->compressed_len == s->bits_sent, "bad compressed size"); + init_block(s); + + if (eof) { + bi_windup(s); + s->compressed_len += 7; /* align on byte boundary */ + } + Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3, + s->compressed_len-7*eof)); + + return s->compressed_len >> 3; +} + +/* =========================================================================== + * Save the match info and tally the frequency counts. Return true if + * the current block must be flushed. + */ +local int ct_tally (s, dist, lc) + deflate_state *s; + int dist; /* distance of matched string */ + int lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */ +{ + s->d_buf[s->last_lit] = (ush)dist; + s->l_buf[s->last_lit++] = (uch)lc; + if (dist == 0) { + /* lc is the unmatched char */ + s->dyn_ltree[lc].Freq++; + } else { + s->matches++; + /* Here, lc is the match length - MIN_MATCH */ + dist--; /* dist = match distance - 1 */ + Assert((ush)dist < (ush)MAX_DIST(s) && + (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) && + (ush)d_code(dist) < (ush)D_CODES, "ct_tally: bad match"); + + s->dyn_ltree[length_code[lc]+LITERALS+1].Freq++; + s->dyn_dtree[d_code(dist)].Freq++; + } + + /* Try to guess if it is profitable to stop the current block here */ + if (s->level > 2 && (s->last_lit & 0xfff) == 0) { + /* Compute an upper bound for the compressed length */ + ulg out_length = (ulg)s->last_lit*8L; + ulg in_length = (ulg)s->strstart - s->block_start; + int dcode; + for (dcode = 0; dcode < D_CODES; dcode++) { + out_length += (ulg)s->dyn_dtree[dcode].Freq * + (5L+extra_dbits[dcode]); + } + out_length >>= 3; + Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ", + s->last_lit, in_length, out_length, + 100L - out_length*100L/in_length)); + if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1; + } + return (s->last_lit == s->lit_bufsize-1); + /* We avoid equality with lit_bufsize because of wraparound at 64K + * on 16 bit machines and because stored blocks are restricted to + * 64K-1 bytes. + */ +} + +/* =========================================================================== + * Send the block data compressed using the given Huffman trees + */ +local void compress_block(s, ltree, dtree) + deflate_state *s; + ct_data *ltree; /* literal tree */ + ct_data *dtree; /* distance tree */ +{ + unsigned dist; /* distance of matched string */ + int lc; /* match length or unmatched char (if dist == 0) */ + unsigned lx = 0; /* running index in l_buf */ + unsigned code; /* the code to send */ + int extra; /* number of extra bits to send */ + + if (s->last_lit != 0) do { + dist = s->d_buf[lx]; + lc = s->l_buf[lx++]; + if (dist == 0) { + send_code(s, lc, ltree); /* send a literal byte */ + Tracecv(isgraph(lc), (stderr," '%c' ", lc)); + } else { + /* Here, lc is the match length - MIN_MATCH */ + code = length_code[lc]; + send_code(s, code+LITERALS+1, ltree); /* send the length code */ + extra = extra_lbits[code]; + if (extra != 0) { + lc -= base_length[code]; + send_bits(s, lc, extra); /* send the extra length bits */ + } + dist--; /* dist is now the match distance - 1 */ + code = d_code(dist); + Assert (code < D_CODES, "bad d_code"); + + send_code(s, code, dtree); /* send the distance code */ + extra = extra_dbits[code]; + if (extra != 0) { + dist -= base_dist[code]; + send_bits(s, dist, extra); /* send the extra distance bits */ + } + } /* literal or match pair ? */ + + /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */ + Assert(s->pending < s->lit_bufsize + 2*lx, "pendingBuf overflow"); + + } while (lx < s->last_lit); + + send_code(s, END_BLOCK, ltree); + s->last_eob_len = ltree[END_BLOCK].Len; +} + +/* =========================================================================== + * Set the data type to ASCII or Z_BINARY, using a crude approximation: + * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise. + * IN assertion: the fields freq of dyn_ltree are set and the total of all + * frequencies does not exceed 64K (to fit in an int on 16 bit machines). + */ +local void set_data_type(s) + deflate_state *s; +{ + int n = 0; + unsigned ascii_freq = 0; + unsigned bin_freq = 0; + while (n < 7) bin_freq += s->dyn_ltree[n++].Freq; + while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq; + while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq; + s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? Z_BINARY : ASCII); +} + +/* =========================================================================== + * Reverse the first len bits of a code, using straightforward code (a faster + * method would use a table) + * IN assertion: 1 <= len <= 15 + */ +local unsigned bi_reverse(code, len) + unsigned code; /* the value to invert */ + int len; /* its bit length */ +{ + register unsigned res = 0; + do { + res |= code & 1; + code >>= 1, res <<= 1; + } while (--len > 0); + return res >> 1; +} + +/* =========================================================================== + * Flush the bit buffer, keeping at most 7 bits in it. + */ +local void bi_flush(s) + deflate_state *s; +{ + if (s->bi_valid == 16) { + put_short(s, s->bi_buf); + s->bi_buf = 0; + s->bi_valid = 0; + } else if (s->bi_valid >= 8) { + put_byte(s, (Byte)s->bi_buf); + s->bi_buf >>= 8; + s->bi_valid -= 8; + } +} + +/* =========================================================================== + * Flush the bit buffer and align the output on a byte boundary + */ +local void bi_windup(s) + deflate_state *s; +{ + if (s->bi_valid > 8) { + put_short(s, s->bi_buf); + } else if (s->bi_valid > 0) { + put_byte(s, (Byte)s->bi_buf); + } + s->bi_buf = 0; + s->bi_valid = 0; +#ifdef DEBUG_ZLIB + s->bits_sent = (s->bits_sent+7) & ~7; +#endif +} + +/* =========================================================================== + * Copy a stored block, storing first the length and its + * one's complement if requested. + */ +local void copy_block(s, buf, len, header) + deflate_state *s; + charf *buf; /* the input data */ + unsigned len; /* its length */ + int header; /* true if block header must be written */ +{ + bi_windup(s); /* align on byte boundary */ + s->last_eob_len = 8; /* enough lookahead for inflate */ + + if (header) { + put_short(s, (ush)len); + put_short(s, (ush)~len); +#ifdef DEBUG_ZLIB + s->bits_sent += 2*16; +#endif + } +#ifdef DEBUG_ZLIB + s->bits_sent += (ulg)len<<3; +#endif + while (len--) { + put_byte(s, *buf++); + } +} + + +/*+++++*/ +/* infblock.h -- header to use infblock.c + * Copyright (C) 1995 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* WARNING: this file should *not* be used by applications. It is + part of the implementation of the compression library and is + subject to change. Applications should only use zlib.h. + */ + +struct inflate_blocks_state; +typedef struct inflate_blocks_state FAR inflate_blocks_statef; + +local inflate_blocks_statef * inflate_blocks_new OF(( + z_stream *z, + check_func c, /* check function */ + uInt w)); /* window size */ + +local int inflate_blocks OF(( + inflate_blocks_statef *, + z_stream *, + int)); /* initial return code */ + +local void inflate_blocks_reset OF(( + inflate_blocks_statef *, + z_stream *, + uLongf *)); /* check value on output */ + +local int inflate_blocks_free OF(( + inflate_blocks_statef *, + z_stream *, + uLongf *)); /* check value on output */ + +local int inflate_addhistory OF(( + inflate_blocks_statef *, + z_stream *)); + +local int inflate_packet_flush OF(( + inflate_blocks_statef *)); + +/*+++++*/ +/* inftrees.h -- header to use inftrees.c + * Copyright (C) 1995 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* WARNING: this file should *not* be used by applications. It is + part of the implementation of the compression library and is + subject to change. Applications should only use zlib.h. + */ + +/* Huffman code lookup table entry--this entry is four bytes for machines + that have 16-bit pointers (e.g. PC's in the small or medium model). */ + +typedef struct inflate_huft_s FAR inflate_huft; + +struct inflate_huft_s { + union { + struct { + Byte Exop; /* number of extra bits or operation */ + Byte Bits; /* number of bits in this code or subcode */ + } what; + uInt Nalloc; /* number of these allocated here */ + Bytef *pad; /* pad structure to a power of 2 (4 bytes for */ + } word; /* 16-bit, 8 bytes for 32-bit machines) */ + union { + uInt Base; /* literal, length base, or distance base */ + inflate_huft *Next; /* pointer to next level of table */ + } more; +}; + +#ifdef DEBUG_ZLIB + local uInt inflate_hufts; +#endif + +local int inflate_trees_bits OF(( + uIntf *, /* 19 code lengths */ + uIntf *, /* bits tree desired/actual depth */ + inflate_huft * FAR *, /* bits tree result */ + z_stream *)); /* for zalloc, zfree functions */ + +local int inflate_trees_dynamic OF(( + uInt, /* number of literal/length codes */ + uInt, /* number of distance codes */ + uIntf *, /* that many (total) code lengths */ + uIntf *, /* literal desired/actual bit depth */ + uIntf *, /* distance desired/actual bit depth */ + inflate_huft * FAR *, /* literal/length tree result */ + inflate_huft * FAR *, /* distance tree result */ + z_stream *)); /* for zalloc, zfree functions */ + +local int inflate_trees_fixed OF(( + uIntf *, /* literal desired/actual bit depth */ + uIntf *, /* distance desired/actual bit depth */ + inflate_huft * FAR *, /* literal/length tree result */ + inflate_huft * FAR *)); /* distance tree result */ + +local int inflate_trees_free OF(( + inflate_huft *, /* tables to free */ + z_stream *)); /* for zfree function */ + + +/*+++++*/ +/* infcodes.h -- header to use infcodes.c + * Copyright (C) 1995 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* WARNING: this file should *not* be used by applications. It is + part of the implementation of the compression library and is + subject to change. Applications should only use zlib.h. + */ + +struct inflate_codes_state; +typedef struct inflate_codes_state FAR inflate_codes_statef; + +local inflate_codes_statef *inflate_codes_new OF(( + uInt, uInt, + inflate_huft *, inflate_huft *, + z_stream *)); + +local int inflate_codes OF(( + inflate_blocks_statef *, + z_stream *, + int)); + +local void inflate_codes_free OF(( + inflate_codes_statef *, + z_stream *)); + + +/*+++++*/ +/* inflate.c -- zlib interface to inflate modules + * Copyright (C) 1995 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* inflate private state */ +struct internal_state { + + /* mode */ + enum { + METHOD, /* waiting for method byte */ + FLAG, /* waiting for flag byte */ + BLOCKS, /* decompressing blocks */ + CHECK4, /* four check bytes to go */ + CHECK3, /* three check bytes to go */ + CHECK2, /* two check bytes to go */ + CHECK1, /* one check byte to go */ + DONE, /* finished check, done */ + BAD} /* got an error--stay here */ + mode; /* current inflate mode */ + + /* mode dependent information */ + union { + uInt method; /* if FLAGS, method byte */ + struct { + uLong was; /* computed check value */ + uLong need; /* stream check value */ + } check; /* if CHECK, check values to compare */ + uInt marker; /* if BAD, inflateSync's marker bytes count */ + } sub; /* submode */ + + /* mode independent information */ + int nowrap; /* flag for no wrapper */ + uInt wbits; /* log2(window size) (8..15, defaults to 15) */ + inflate_blocks_statef + *blocks; /* current inflate_blocks state */ + +}; + + +int inflateReset(z) +z_stream *z; +{ + uLong c; + + if (z == Z_NULL || z->state == Z_NULL) + return Z_STREAM_ERROR; + z->total_in = z->total_out = 0; + z->msg = Z_NULL; + z->state->mode = z->state->nowrap ? BLOCKS : METHOD; + inflate_blocks_reset(z->state->blocks, z, &c); + Trace((stderr, "inflate: reset\n")); + return Z_OK; +} + + +int inflateEnd(z) +z_stream *z; +{ + uLong c; + + if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL) + return Z_STREAM_ERROR; + if (z->state->blocks != Z_NULL) + inflate_blocks_free(z->state->blocks, z, &c); + ZFREE(z, z->state, sizeof(struct internal_state)); + z->state = Z_NULL; + Trace((stderr, "inflate: end\n")); + return Z_OK; +} + + +int inflateInit2(z, w) +z_stream *z; +int w; +{ + /* initialize state */ + if (z == Z_NULL) + return Z_STREAM_ERROR; +/* if (z->zalloc == Z_NULL) z->zalloc = zcalloc; */ +/* if (z->zfree == Z_NULL) z->zfree = zcfree; */ + if ((z->state = (struct internal_state FAR *) + ZALLOC_INIT(z,1,sizeof(struct internal_state))) == Z_NULL) + return Z_MEM_ERROR; + z->state->blocks = Z_NULL; + + /* handle undocumented nowrap option (no zlib header or check) */ + z->state->nowrap = 0; + if (w < 0) + { + w = - w; + z->state->nowrap = 1; + } + + /* set window size */ + if (w < 8 || w > 15) + { + inflateEnd(z); + return Z_STREAM_ERROR; + } + z->state->wbits = (uInt)w; + + /* create inflate_blocks state */ + if ((z->state->blocks = + inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, 1 << w)) + == Z_NULL) + { + inflateEnd(z); + return Z_MEM_ERROR; + } + Trace((stderr, "inflate: allocated\n")); + + /* reset state */ + inflateReset(z); + return Z_OK; +} + + +int inflateInit(z) +z_stream *z; +{ + return inflateInit2(z, DEF_WBITS); +} + + +#define NEEDBYTE {if(z->avail_in==0)goto empty;r=Z_OK;} +#define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++) + +int inflate(z, f) +z_stream *z; +int f; +{ + int r; + uInt b; + + if (z == Z_NULL || z->next_in == Z_NULL) + return Z_STREAM_ERROR; + r = Z_BUF_ERROR; + while (1) switch (z->state->mode) + { + case METHOD: + NEEDBYTE + if (((z->state->sub.method = NEXTBYTE) & 0xf) != DEFLATED) + { + z->state->mode = BAD; + z->msg = "unknown compression method"; + z->state->sub.marker = 5; /* can't try inflateSync */ + break; + } + if ((z->state->sub.method >> 4) + 8 > z->state->wbits) + { + z->state->mode = BAD; + z->msg = "invalid window size"; + z->state->sub.marker = 5; /* can't try inflateSync */ + break; + } + z->state->mode = FLAG; + case FLAG: + NEEDBYTE + if ((b = NEXTBYTE) & 0x20) + { + z->state->mode = BAD; + z->msg = "invalid reserved bit"; + z->state->sub.marker = 5; /* can't try inflateSync */ + break; + } + if (((z->state->sub.method << 8) + b) % 31) + { + z->state->mode = BAD; + z->msg = "incorrect header check"; + z->state->sub.marker = 5; /* can't try inflateSync */ + break; + } + Trace((stderr, "inflate: zlib header ok\n")); + z->state->mode = BLOCKS; + case BLOCKS: + r = inflate_blocks(z->state->blocks, z, r); + if (f == Z_PACKET_FLUSH && z->avail_in == 0 && z->avail_out != 0) + r = inflate_packet_flush(z->state->blocks); + if (r == Z_DATA_ERROR) + { + z->state->mode = BAD; + z->state->sub.marker = 0; /* can try inflateSync */ + break; + } + if (r != Z_STREAM_END) + return r; + r = Z_OK; + inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was); + if (z->state->nowrap) + { + z->state->mode = DONE; + break; + } + z->state->mode = CHECK4; + case CHECK4: + NEEDBYTE + z->state->sub.check.need = (uLong)NEXTBYTE << 24; + z->state->mode = CHECK3; + case CHECK3: + NEEDBYTE + z->state->sub.check.need += (uLong)NEXTBYTE << 16; + z->state->mode = CHECK2; + case CHECK2: + NEEDBYTE + z->state->sub.check.need += (uLong)NEXTBYTE << 8; + z->state->mode = CHECK1; + case CHECK1: + NEEDBYTE + z->state->sub.check.need += (uLong)NEXTBYTE; + + if (z->state->sub.check.was != z->state->sub.check.need) + { + z->state->mode = BAD; + z->msg = "incorrect data check"; + z->state->sub.marker = 5; /* can't try inflateSync */ + break; + } + Trace((stderr, "inflate: zlib check ok\n")); + z->state->mode = DONE; + case DONE: + return Z_STREAM_END; + case BAD: + return Z_DATA_ERROR; + default: + return Z_STREAM_ERROR; + } + + empty: + if (f != Z_PACKET_FLUSH) + return r; + z->state->mode = BAD; + z->state->sub.marker = 0; /* can try inflateSync */ + return Z_DATA_ERROR; +} + +/* + * This subroutine adds the data at next_in/avail_in to the output history + * without performing any output. The output buffer must be "caught up"; + * i.e. no pending output (hence s->read equals s->write), and the state must + * be BLOCKS (i.e. we should be willing to see the start of a series of + * BLOCKS). On exit, the output will also be caught up, and the checksum + * will have been updated if need be. + */ + +int inflateIncomp(z) +z_stream *z; +{ + if (z->state->mode != BLOCKS) + return Z_DATA_ERROR; + return inflate_addhistory(z->state->blocks, z); +} + + +int inflateSync(z) +z_stream *z; +{ + uInt n; /* number of bytes to look at */ + Bytef *p; /* pointer to bytes */ + uInt m; /* number of marker bytes found in a row */ + uLong r, w; /* temporaries to save total_in and total_out */ + + /* set up */ + if (z == Z_NULL || z->state == Z_NULL) + return Z_STREAM_ERROR; + if (z->state->mode != BAD) + { + z->state->mode = BAD; + z->state->sub.marker = 0; + } + if ((n = z->avail_in) == 0) + return Z_BUF_ERROR; + p = z->next_in; + m = z->state->sub.marker; + + /* search */ + while (n && m < 4) + { + if (*p == (Byte)(m < 2 ? 0 : 0xff)) + m++; + else if (*p) + m = 0; + else + m = 4 - m; + p++, n--; + } + + /* restore */ + z->total_in += p - z->next_in; + z->next_in = p; + z->avail_in = n; + z->state->sub.marker = m; + + /* return no joy or set up to restart on a new block */ + if (m != 4) + return Z_DATA_ERROR; + r = z->total_in; w = z->total_out; + inflateReset(z); + z->total_in = r; z->total_out = w; + z->state->mode = BLOCKS; + return Z_OK; +} + +#undef NEEDBYTE +#undef NEXTBYTE + +/*+++++*/ +/* infutil.h -- types and macros common to blocks and codes + * Copyright (C) 1995 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* WARNING: this file should *not* be used by applications. It is + part of the implementation of the compression library and is + subject to change. Applications should only use zlib.h. + */ + +/* inflate blocks semi-private state */ +struct inflate_blocks_state { + + /* mode */ + enum { + TYPE, /* get type bits (3, including end bit) */ + LENS, /* get lengths for stored */ + STORED, /* processing stored block */ + TABLE, /* get table lengths */ + BTREE, /* get bit lengths tree for a dynamic block */ + DTREE, /* get length, distance trees for a dynamic block */ + CODES, /* processing fixed or dynamic block */ + DRY, /* output remaining window bytes */ + DONEB, /* finished last block, done */ + BADB} /* got a data error--stuck here */ + mode; /* current inflate_block mode */ + + /* mode dependent information */ + union { + uInt left; /* if STORED, bytes left to copy */ + struct { + uInt table; /* table lengths (14 bits) */ + uInt index; /* index into blens (or border) */ + uIntf *blens; /* bit lengths of codes */ + uInt bb; /* bit length tree depth */ + inflate_huft *tb; /* bit length decoding tree */ + int nblens; /* # elements allocated at blens */ + } trees; /* if DTREE, decoding info for trees */ + struct { + inflate_huft *tl, *td; /* trees to free */ + inflate_codes_statef + *codes; + } decode; /* if CODES, current state */ + } sub; /* submode */ + uInt last; /* true if this block is the last block */ + + /* mode independent information */ + uInt bitk; /* bits in bit buffer */ + uLong bitb; /* bit buffer */ + Bytef *window; /* sliding window */ + Bytef *end; /* one byte after sliding window */ + Bytef *read; /* window read pointer */ + Bytef *write; /* window write pointer */ + check_func checkfn; /* check function */ + uLong check; /* check on output */ + +}; + + +/* defines for inflate input/output */ +/* update pointers and return */ +#define UPDBITS {s->bitb=b;s->bitk=k;} +#define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;} +#define UPDOUT {s->write=q;} +#define UPDATE {UPDBITS UPDIN UPDOUT} +#define LEAVE {UPDATE return inflate_flush(s,z,r);} +/* get bytes and bits */ +#define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;} +#define NEEDBYTE {if(n)r=Z_OK;else LEAVE} +#define NEXTBYTE (n--,*p++) +#define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}} +#define DUMPBITS(j) {b>>=(j);k-=(j);} +/* output bytes */ +#define WAVAIL (q<s->read?s->read-q-1:s->end-q) +#define LOADOUT {q=s->write;m=WAVAIL;} +#define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=WAVAIL;}} +#define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT} +#define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;} +#define OUTBYTE(a) {*q++=(Byte)(a);m--;} +/* load local pointers */ +#define LOAD {LOADIN LOADOUT} + +/* And'ing with mask[n] masks the lower n bits */ +local uInt inflate_mask[] = { + 0x0000, + 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff, + 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff +}; + +/* copy as much as possible from the sliding window to the output area */ +local int inflate_flush OF(( + inflate_blocks_statef *, + z_stream *, + int)); + +/*+++++*/ +/* inffast.h -- header to use inffast.c + * Copyright (C) 1995 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* WARNING: this file should *not* be used by applications. It is + part of the implementation of the compression library and is + subject to change. Applications should only use zlib.h. + */ + +local int inflate_fast OF(( + uInt, + uInt, + inflate_huft *, + inflate_huft *, + inflate_blocks_statef *, + z_stream *)); + + +/*+++++*/ +/* infblock.c -- interpret and process block types to last block + * Copyright (C) 1995 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* Table for deflate from PKZIP's appnote.txt. */ +local uInt border[] = { /* Order of the bit length code lengths */ + 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; + +/* + Notes beyond the 1.93a appnote.txt: + + 1. Distance pointers never point before the beginning of the output + stream. + 2. Distance pointers can point back across blocks, up to 32k away. + 3. There is an implied maximum of 7 bits for the bit length table and + 15 bits for the actual data. + 4. If only one code exists, then it is encoded using one bit. (Zero + would be more efficient, but perhaps a little confusing.) If two + codes exist, they are coded using one bit each (0 and 1). + 5. There is no way of sending zero distance codes--a dummy must be + sent if there are none. (History: a pre 2.0 version of PKZIP would + store blocks with no distance codes, but this was discovered to be + too harsh a criterion.) Valid only for 1.93a. 2.04c does allow + zero distance codes, which is sent as one code of zero bits in + length. + 6. There are up to 286 literal/length codes. Code 256 represents the + end-of-block. Note however that the static length tree defines + 288 codes just to fill out the Huffman codes. Codes 286 and 287 + cannot be used though, since there is no length base or extra bits + defined for them. Similarily, there are up to 30 distance codes. + However, static trees define 32 codes (all 5 bits) to fill out the + Huffman codes, but the last two had better not show up in the data. + 7. Unzip can check dynamic Huffman blocks for complete code sets. + The exception is that a single code would not be complete (see #4). + 8. The five bits following the block type is really the number of + literal codes sent minus 257. + 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits + (1+6+6). Therefore, to output three times the length, you output + three codes (1+1+1), whereas to output four times the same length, + you only need two codes (1+3). Hmm. + 10. In the tree reconstruction algorithm, Code = Code + Increment + only if BitLength(i) is not zero. (Pretty obvious.) + 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19) + 12. Note: length code 284 can represent 227-258, but length code 285 + really is 258. The last length deserves its own, short code + since it gets used a lot in very redundant files. The length + 258 is special since 258 - 3 (the min match length) is 255. + 13. The literal/length and distance code bit lengths are read as a + single stream of lengths. It is possible (and advantageous) for + a repeat code (16, 17, or 18) to go across the boundary between + the two sets of lengths. + */ + + +local void inflate_blocks_reset(s, z, c) +inflate_blocks_statef *s; +z_stream *z; +uLongf *c; +{ + if (s->checkfn != Z_NULL) + *c = s->check; + if (s->mode == BTREE || s->mode == DTREE) + ZFREE(z, s->sub.trees.blens, s->sub.trees.nblens * sizeof(uInt)); + if (s->mode == CODES) + { + inflate_codes_free(s->sub.decode.codes, z); + inflate_trees_free(s->sub.decode.td, z); + inflate_trees_free(s->sub.decode.tl, z); + } + s->mode = TYPE; + s->bitk = 0; + s->bitb = 0; + s->read = s->write = s->window; + if (s->checkfn != Z_NULL) + s->check = (*s->checkfn)(0L, Z_NULL, 0); + Trace((stderr, "inflate: blocks reset\n")); +} + + +local inflate_blocks_statef *inflate_blocks_new(z, c, w) +z_stream *z; +check_func c; +uInt w; +{ + inflate_blocks_statef *s; + + if ((s = (inflate_blocks_statef *)ZALLOC_INIT + (z,1,sizeof(struct inflate_blocks_state))) == Z_NULL) + return s; + if ((s->window = (Bytef *)ZALLOC_INIT(z, 1, w)) == Z_NULL) + { + ZFREE(z, s, sizeof(struct inflate_blocks_state)); + return Z_NULL; + } + s->end = s->window + w; + s->checkfn = c; + s->mode = TYPE; + Trace((stderr, "inflate: blocks allocated\n")); + inflate_blocks_reset(s, z, &s->check); + return s; +} + + +local int inflate_blocks(s, z, r) +inflate_blocks_statef *s; +z_stream *z; +int r; +{ + uInt t; /* temporary storage */ + uLong b; /* bit buffer */ + uInt k; /* bits in bit buffer */ + Bytef *p; /* input data pointer */ + uInt n; /* bytes available there */ + Bytef *q; /* output window write pointer */ + uInt m; /* bytes to end of window or read pointer */ + + /* copy input/output information to locals (UPDATE macro restores) */ + LOAD + + /* process input based on current state */ + while (1) switch (s->mode) + { + case TYPE: + NEEDBITS(3) + t = (uInt)b & 7; + s->last = t & 1; + switch (t >> 1) + { + case 0: /* stored */ + Trace((stderr, "inflate: stored block%s\n", + s->last ? " (last)" : "")); + DUMPBITS(3) + t = k & 7; /* go to byte boundary */ + DUMPBITS(t) + s->mode = LENS; /* get length of stored block */ + break; + case 1: /* fixed */ + Trace((stderr, "inflate: fixed codes block%s\n", + s->last ? " (last)" : "")); + { + uInt bl, bd; + inflate_huft *tl, *td; + + inflate_trees_fixed(&bl, &bd, &tl, &td); + s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z); + if (s->sub.decode.codes == Z_NULL) + { + r = Z_MEM_ERROR; + LEAVE + } + s->sub.decode.tl = Z_NULL; /* don't try to free these */ + s->sub.decode.td = Z_NULL; + } + DUMPBITS(3) + s->mode = CODES; + break; + case 2: /* dynamic */ + Trace((stderr, "inflate: dynamic codes block%s\n", + s->last ? " (last)" : "")); + DUMPBITS(3) + s->mode = TABLE; + break; + case 3: /* illegal */ + DUMPBITS(3) + s->mode = BADB; + z->msg = "invalid block type"; + r = Z_DATA_ERROR; + LEAVE + } + break; + case LENS: + NEEDBITS(32) + if (((~b) >> 16) != (b & 0xffff)) + { + s->mode = BADB; + z->msg = "invalid stored block lengths"; + r = Z_DATA_ERROR; + LEAVE + } + s->sub.left = (uInt)b & 0xffff; + b = k = 0; /* dump bits */ + Tracev((stderr, "inflate: stored length %u\n", s->sub.left)); + s->mode = s->sub.left ? STORED : TYPE; + break; + case STORED: + if (n == 0) + LEAVE + NEEDOUT + t = s->sub.left; + if (t > n) t = n; + if (t > m) t = m; + zmemcpy(q, p, t); + p += t; n -= t; + q += t; m -= t; + if ((s->sub.left -= t) != 0) + break; + Tracev((stderr, "inflate: stored end, %lu total out\n", + z->total_out + (q >= s->read ? q - s->read : + (s->end - s->read) + (q - s->window)))); + s->mode = s->last ? DRY : TYPE; + break; + case TABLE: + NEEDBITS(14) + s->sub.trees.table = t = (uInt)b & 0x3fff; +#ifndef PKZIP_BUG_WORKAROUND + if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29) + { + s->mode = BADB; + z->msg = "too many length or distance symbols"; + r = Z_DATA_ERROR; + LEAVE + } +#endif + t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f); + if (t < 19) + t = 19; + if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL) + { + r = Z_MEM_ERROR; + LEAVE + } + s->sub.trees.nblens = t; + DUMPBITS(14) + s->sub.trees.index = 0; + Tracev((stderr, "inflate: table sizes ok\n")); + s->mode = BTREE; + case BTREE: + while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10)) + { + NEEDBITS(3) + s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7; + DUMPBITS(3) + } + while (s->sub.trees.index < 19) + s->sub.trees.blens[border[s->sub.trees.index++]] = 0; + s->sub.trees.bb = 7; + t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb, + &s->sub.trees.tb, z); + if (t != Z_OK) + { + r = t; + if (r == Z_DATA_ERROR) + s->mode = BADB; + LEAVE + } + s->sub.trees.index = 0; + Tracev((stderr, "inflate: bits tree ok\n")); + s->mode = DTREE; + case DTREE: + while (t = s->sub.trees.table, + s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f)) + { + inflate_huft *h; + uInt i, j, c; + + t = s->sub.trees.bb; + NEEDBITS(t) + h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]); + t = h->word.what.Bits; + c = h->more.Base; + if (c < 16) + { + DUMPBITS(t) + s->sub.trees.blens[s->sub.trees.index++] = c; + } + else /* c == 16..18 */ + { + i = c == 18 ? 7 : c - 14; + j = c == 18 ? 11 : 3; + NEEDBITS(t + i) + DUMPBITS(t) + j += (uInt)b & inflate_mask[i]; + DUMPBITS(i) + i = s->sub.trees.index; + t = s->sub.trees.table; + if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) || + (c == 16 && i < 1)) + { + s->mode = BADB; + z->msg = "invalid bit length repeat"; + r = Z_DATA_ERROR; + LEAVE + } + c = c == 16 ? s->sub.trees.blens[i - 1] : 0; + do { + s->sub.trees.blens[i++] = c; + } while (--j); + s->sub.trees.index = i; + } + } + inflate_trees_free(s->sub.trees.tb, z); + s->sub.trees.tb = Z_NULL; + { + uInt bl, bd; + inflate_huft *tl, *td; + inflate_codes_statef *c; + + bl = 9; /* must be <= 9 for lookahead assumptions */ + bd = 6; /* must be <= 9 for lookahead assumptions */ + t = s->sub.trees.table; + t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f), + s->sub.trees.blens, &bl, &bd, &tl, &td, z); + if (t != Z_OK) + { + if (t == (uInt)Z_DATA_ERROR) + s->mode = BADB; + r = t; + LEAVE + } + Tracev((stderr, "inflate: trees ok\n")); + if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL) + { + inflate_trees_free(td, z); + inflate_trees_free(tl, z); + r = Z_MEM_ERROR; + LEAVE + } + ZFREE(z, s->sub.trees.blens, s->sub.trees.nblens * sizeof(uInt)); + s->sub.decode.codes = c; + s->sub.decode.tl = tl; + s->sub.decode.td = td; + } + s->mode = CODES; + case CODES: + UPDATE + if ((r = inflate_codes(s, z, r)) != Z_STREAM_END) + return inflate_flush(s, z, r); + r = Z_OK; + inflate_codes_free(s->sub.decode.codes, z); + inflate_trees_free(s->sub.decode.td, z); + inflate_trees_free(s->sub.decode.tl, z); + LOAD + Tracev((stderr, "inflate: codes end, %lu total out\n", + z->total_out + (q >= s->read ? q - s->read : + (s->end - s->read) + (q - s->window)))); + if (!s->last) + { + s->mode = TYPE; + break; + } + if (k > 7) /* return unused byte, if any */ + { + Assert(k < 16, "inflate_codes grabbed too many bytes") + k -= 8; + n++; + p--; /* can always return one */ + } + s->mode = DRY; + case DRY: + FLUSH + if (s->read != s->write) + LEAVE + s->mode = DONEB; + case DONEB: + r = Z_STREAM_END; + LEAVE + case BADB: + r = Z_DATA_ERROR; + LEAVE + default: + r = Z_STREAM_ERROR; + LEAVE + } +} + + +local int inflate_blocks_free(s, z, c) +inflate_blocks_statef *s; +z_stream *z; +uLongf *c; +{ + inflate_blocks_reset(s, z, c); + ZFREE(z, s->window, s->end - s->window); + ZFREE(z, s, sizeof(struct inflate_blocks_state)); + Trace((stderr, "inflate: blocks freed\n")); + return Z_OK; +} + +/* + * This subroutine adds the data at next_in/avail_in to the output history + * without performing any output. The output buffer must be "caught up"; + * i.e. no pending output (hence s->read equals s->write), and the state must + * be BLOCKS (i.e. we should be willing to see the start of a series of + * BLOCKS). On exit, the output will also be caught up, and the checksum + * will have been updated if need be. + */ +local int inflate_addhistory(s, z) +inflate_blocks_statef *s; +z_stream *z; +{ + uLong b; /* bit buffer */ /* NOT USED HERE */ + uInt k; /* bits in bit buffer */ /* NOT USED HERE */ + uInt t; /* temporary storage */ + Bytef *p; /* input data pointer */ + uInt n; /* bytes available there */ + Bytef *q; /* output window write pointer */ + uInt m; /* bytes to end of window or read pointer */ + + if (s->read != s->write) + return Z_STREAM_ERROR; + if (s->mode != TYPE) + return Z_DATA_ERROR; + + /* we're ready to rock */ + LOAD + /* while there is input ready, copy to output buffer, moving + * pointers as needed. + */ + while (n) { + t = n; /* how many to do */ + /* is there room until end of buffer? */ + if (t > m) t = m; + /* update check information */ + if (s->checkfn != Z_NULL) + s->check = (*s->checkfn)(s->check, q, t); + zmemcpy(q, p, t); + q += t; + p += t; + n -= t; + z->total_out += t; + s->read = q; /* drag read pointer forward */ +/* WRAP */ /* expand WRAP macro by hand to handle s->read */ + if (q == s->end) { + s->read = q = s->window; + m = WAVAIL; + } + } + UPDATE + return Z_OK; +} + + +/* + * At the end of a Deflate-compressed PPP packet, we expect to have seen + * a `stored' block type value but not the (zero) length bytes. + */ +local int inflate_packet_flush(s) + inflate_blocks_statef *s; +{ + if (s->mode != LENS) + return Z_DATA_ERROR; + s->mode = TYPE; + return Z_OK; +} + + +/*+++++*/ +/* inftrees.c -- generate Huffman trees for efficient decoding + * Copyright (C) 1995 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* simplify the use of the inflate_huft type with some defines */ +#define base more.Base +#define next more.Next +#define exop word.what.Exop +#define bits word.what.Bits + + +local int huft_build OF(( + uIntf *, /* code lengths in bits */ + uInt, /* number of codes */ + uInt, /* number of "simple" codes */ + uIntf *, /* list of base values for non-simple codes */ + uIntf *, /* list of extra bits for non-simple codes */ + inflate_huft * FAR*,/* result: starting table */ + uIntf *, /* maximum lookup bits (returns actual) */ + z_stream *)); /* for zalloc function */ + +local voidpf falloc OF(( + voidpf, /* opaque pointer (not used) */ + uInt, /* number of items */ + uInt)); /* size of item */ + +local void ffree OF(( + voidpf q, /* opaque pointer (not used) */ + voidpf p, /* what to free (not used) */ + uInt n)); /* number of bytes (not used) */ + +/* Tables for deflate from PKZIP's appnote.txt. */ +local uInt cplens[] = { /* Copy lengths for literal codes 257..285 */ + 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, + 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0}; + /* actually lengths - 2; also see note #13 above about 258 */ +local uInt cplext[] = { /* Extra bits for literal codes 257..285 */ + 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, 192, 192}; /* 192==invalid */ +local uInt cpdist[] = { /* Copy offsets for distance codes 0..29 */ + 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, + 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, + 8193, 12289, 16385, 24577}; +local uInt cpdext[] = { /* Extra bits for distance codes */ + 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}; + +/* + Huffman code decoding is performed using a multi-level table lookup. + The fastest way to decode is to simply build a lookup table whose + size is determined by the longest code. However, the time it takes + to build this table can also be a factor if the data being decoded + is not very long. The most common codes are necessarily the + shortest codes, so those codes dominate the decoding time, and hence + the speed. The idea is you can have a shorter table that decodes the + shorter, more probable codes, and then point to subsidiary tables for + the longer codes. The time it costs to decode the longer codes is + then traded against the time it takes to make longer tables. + + This results of this trade are in the variables lbits and dbits + below. lbits is the number of bits the first level table for literal/ + length codes can decode in one step, and dbits is the same thing for + the distance codes. Subsequent tables are also less than or equal to + those sizes. These values may be adjusted either when all of the + codes are shorter than that, in which case the longest code length in + bits is used, or when the shortest code is *longer* than the requested + table size, in which case the length of the shortest code in bits is + used. + + There are two different values for the two tables, since they code a + different number of possibilities each. The literal/length table + codes 286 possible values, or in a flat code, a little over eight + bits. The distance table codes 30 possible values, or a little less + than five bits, flat. The optimum values for speed end up being + about one bit more than those, so lbits is 8+1 and dbits is 5+1. + The optimum values may differ though from machine to machine, and + possibly even between compilers. Your mileage may vary. + */ + + +/* If BMAX needs to be larger than 16, then h and x[] should be uLong. */ +#define BMAX 15 /* maximum bit length of any code */ +#define N_MAX 288 /* maximum number of codes in any set */ + +#ifdef DEBUG_ZLIB + uInt inflate_hufts; +#endif + +local int huft_build(b, n, s, d, e, t, m, zs) +uIntf *b; /* code lengths in bits (all assumed <= BMAX) */ +uInt n; /* number of codes (assumed <= N_MAX) */ +uInt s; /* number of simple-valued codes (0..s-1) */ +uIntf *d; /* list of base values for non-simple codes */ +uIntf *e; /* list of extra bits for non-simple codes */ +inflate_huft * FAR *t; /* result: starting table */ +uIntf *m; /* maximum lookup bits, returns actual */ +z_stream *zs; /* for zalloc function */ +/* Given a list of code lengths and a maximum table size, make a set of + tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR + if the given code set is incomplete (the tables are still built in this + case), Z_DATA_ERROR if the input is invalid (all zero length codes or an + over-subscribed set of lengths), or Z_MEM_ERROR if not enough memory. */ +{ + + uInt a; /* counter for codes of length k */ + uInt c[BMAX+1]; /* bit length count table */ + uInt f; /* i repeats in table every f entries */ + int g; /* maximum code length */ + int h; /* table level */ + register uInt i; /* counter, current code */ + register uInt j; /* counter */ + register int k; /* number of bits in current code */ + int l; /* bits per table (returned in m) */ + register uIntf *p; /* pointer into c[], b[], or v[] */ + inflate_huft *q; /* points to current table */ + struct inflate_huft_s r; /* table entry for structure assignment */ + inflate_huft *u[BMAX]; /* table stack */ + uInt v[N_MAX]; /* values in order of bit length */ + register int w; /* bits before this table == (l * h) */ + uInt x[BMAX+1]; /* bit offsets, then code stack */ + uIntf *xp; /* pointer into x */ + int y; /* number of dummy codes added */ + uInt z; /* number of entries in current table */ + + + /* Generate counts for each bit length */ + p = c; +#define C0 *p++ = 0; +#define C2 C0 C0 C0 C0 +#define C4 C2 C2 C2 C2 + C4 /* clear c[]--assume BMAX+1 is 16 */ + p = b; i = n; + do { + c[*p++]++; /* assume all entries <= BMAX */ + } while (--i); + if (c[0] == n) /* null input--all zero length codes */ + { + *t = (inflate_huft *)Z_NULL; + *m = 0; + return Z_OK; + } + + + /* Find minimum and maximum length, bound *m by those */ + l = *m; + for (j = 1; j <= BMAX; j++) + if (c[j]) + break; + k = j; /* minimum code length */ + if ((uInt)l < j) + l = j; + for (i = BMAX; i; i--) + if (c[i]) + break; + g = i; /* maximum code length */ + if ((uInt)l > i) + l = i; + *m = l; + + + /* Adjust last length count to fill out codes, if needed */ + for (y = 1 << j; j < i; j++, y <<= 1) + if ((y -= c[j]) < 0) + return Z_DATA_ERROR; + if ((y -= c[i]) < 0) + return Z_DATA_ERROR; + c[i] += y; + + + /* Generate starting offsets into the value table for each length */ + x[1] = j = 0; + p = c + 1; xp = x + 2; + while (--i) { /* note that i == g from above */ + *xp++ = (j += *p++); + } + + + /* Make a table of values in order of bit lengths */ + p = b; i = 0; + do { + if ((j = *p++) != 0) + v[x[j]++] = i; + } while (++i < n); + + + /* Generate the Huffman codes and for each, make the table entries */ + x[0] = i = 0; /* first Huffman code is zero */ + p = v; /* grab values in bit order */ + h = -1; /* no tables yet--level -1 */ + w = -l; /* bits decoded == (l * h) */ + u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */ + q = (inflate_huft *)Z_NULL; /* ditto */ + z = 0; /* ditto */ + + /* go through the bit lengths (k already is bits in shortest code) */ + for (; k <= g; k++) + { + a = c[k]; + while (a--) + { + /* here i is the Huffman code of length k bits for value *p */ + /* make tables up to required level */ + while (k > w + l) + { + h++; + w += l; /* previous table always l bits */ + + /* compute minimum size table less than or equal to l bits */ + z = (z = g - w) > (uInt)l ? l : z; /* table size upper limit */ + if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */ + { /* too few codes for k-w bit table */ + f -= a + 1; /* deduct codes from patterns left */ + xp = c + k; + if (j < z) + while (++j < z) /* try smaller tables up to z bits */ + { + if ((f <<= 1) <= *++xp) + break; /* enough codes to use up j bits */ + f -= *xp; /* else deduct codes from patterns */ + } + } + z = 1 << j; /* table entries for j-bit table */ + + /* allocate and link in new table */ + if ((q = (inflate_huft *)ZALLOC + (zs,z + 1,sizeof(inflate_huft))) == Z_NULL) + { + if (h) + inflate_trees_free(u[0], zs); + return Z_MEM_ERROR; /* not enough memory */ + } + q->word.Nalloc = z + 1; +#ifdef DEBUG_ZLIB + inflate_hufts += z + 1; +#endif + *t = q + 1; /* link to list for huft_free() */ + *(t = &(q->next)) = Z_NULL; + u[h] = ++q; /* table starts after link */ + + /* connect to last table, if there is one */ + if (h) + { + x[h] = i; /* save pattern for backing up */ + r.bits = (Byte)l; /* bits to dump before this table */ + r.exop = (Byte)j; /* bits in this table */ + r.next = q; /* pointer to this table */ + j = i >> (w - l); /* (get around Turbo C bug) */ + u[h-1][j] = r; /* connect to last table */ + } + } + + /* set up table entry in r */ + r.bits = (Byte)(k - w); + if (p >= v + n) + r.exop = 128 + 64; /* out of values--invalid code */ + else if (*p < s) + { + r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */ + r.base = *p++; /* simple code is just the value */ + } + else + { + r.exop = (Byte)e[*p - s] + 16 + 64; /* non-simple--look up in lists */ + r.base = d[*p++ - s]; + } + + /* fill code-like entries with r */ + f = 1 << (k - w); + for (j = i >> w; j < z; j += f) + q[j] = r; + + /* backwards increment the k-bit code i */ + for (j = 1 << (k - 1); i & j; j >>= 1) + i ^= j; + i ^= j; + + /* backup over finished tables */ + while ((i & ((1 << w) - 1)) != x[h]) + { + h--; /* don't need to update q */ + w -= l; + } + } + } + + + /* Return Z_BUF_ERROR if we were given an incomplete table */ + return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK; +} + + +local int inflate_trees_bits(c, bb, tb, z) +uIntf *c; /* 19 code lengths */ +uIntf *bb; /* bits tree desired/actual depth */ +inflate_huft * FAR *tb; /* bits tree result */ +z_stream *z; /* for zfree function */ +{ + int r; + + r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL, tb, bb, z); + if (r == Z_DATA_ERROR) + z->msg = "oversubscribed dynamic bit lengths tree"; + else if (r == Z_BUF_ERROR) + { + inflate_trees_free(*tb, z); + z->msg = "incomplete dynamic bit lengths tree"; + r = Z_DATA_ERROR; + } + return r; +} + + +local int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, z) +uInt nl; /* number of literal/length codes */ +uInt nd; /* number of distance codes */ +uIntf *c; /* that many (total) code lengths */ +uIntf *bl; /* literal desired/actual bit depth */ +uIntf *bd; /* distance desired/actual bit depth */ +inflate_huft * FAR *tl; /* literal/length tree result */ +inflate_huft * FAR *td; /* distance tree result */ +z_stream *z; /* for zfree function */ +{ + int r; + + /* build literal/length tree */ + if ((r = huft_build(c, nl, 257, cplens, cplext, tl, bl, z)) != Z_OK) + { + if (r == Z_DATA_ERROR) + z->msg = "oversubscribed literal/length tree"; + else if (r == Z_BUF_ERROR) + { + inflate_trees_free(*tl, z); + z->msg = "incomplete literal/length tree"; + r = Z_DATA_ERROR; + } + return r; + } + + /* build distance tree */ + if ((r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, z)) != Z_OK) + { + if (r == Z_DATA_ERROR) + z->msg = "oversubscribed literal/length tree"; + else if (r == Z_BUF_ERROR) { +#ifdef PKZIP_BUG_WORKAROUND + r = Z_OK; + } +#else + inflate_trees_free(*td, z); + z->msg = "incomplete literal/length tree"; + r = Z_DATA_ERROR; + } + inflate_trees_free(*tl, z); + return r; +#endif + } + + /* done */ + return Z_OK; +} + + +/* build fixed tables only once--keep them here */ +local int fixed_lock = 0; +local int fixed_built = 0; +#define FIXEDH 530 /* number of hufts used by fixed tables */ +local uInt fixed_left = FIXEDH; +local inflate_huft fixed_mem[FIXEDH]; +local uInt fixed_bl; +local uInt fixed_bd; +local inflate_huft *fixed_tl; +local inflate_huft *fixed_td; + + +local voidpf falloc(q, n, s) +voidpf q; /* opaque pointer (not used) */ +uInt n; /* number of items */ +uInt s; /* size of item */ +{ + Assert(s == sizeof(inflate_huft) && n <= fixed_left, + "inflate_trees falloc overflow"); + if (q) s++; /* to make some compilers happy */ + fixed_left -= n; + return (voidpf)(fixed_mem + fixed_left); +} + + +local void ffree(q, p, n) +voidpf q; +voidpf p; +uInt n; +{ + Assert(0, "inflate_trees ffree called!"); + if (q) q = p; /* to make some compilers happy */ +} + + +local int inflate_trees_fixed(bl, bd, tl, td) +uIntf *bl; /* literal desired/actual bit depth */ +uIntf *bd; /* distance desired/actual bit depth */ +inflate_huft * FAR *tl; /* literal/length tree result */ +inflate_huft * FAR *td; /* distance tree result */ +{ + /* build fixed tables if not built already--lock out other instances */ + while (++fixed_lock > 1) + fixed_lock--; + if (!fixed_built) + { + int k; /* temporary variable */ + unsigned c[288]; /* length list for huft_build */ + z_stream z; /* for falloc function */ + + /* set up fake z_stream for memory routines */ + z.zalloc = falloc; + z.zfree = ffree; + z.opaque = Z_NULL; + + /* literal table */ + for (k = 0; k < 144; k++) + c[k] = 8; + for (; k < 256; k++) + c[k] = 9; + for (; k < 280; k++) + c[k] = 7; + for (; k < 288; k++) + c[k] = 8; + fixed_bl = 7; + huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl, &z); + + /* distance table */ + for (k = 0; k < 30; k++) + c[k] = 5; + fixed_bd = 5; + huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd, &z); + + /* done */ + fixed_built = 1; + } + fixed_lock--; + *bl = fixed_bl; + *bd = fixed_bd; + *tl = fixed_tl; + *td = fixed_td; + return Z_OK; +} + + +local int inflate_trees_free(t, z) +inflate_huft *t; /* table to free */ +z_stream *z; /* for zfree function */ +/* Free the malloc'ed tables built by huft_build(), which makes a linked + list of the tables it made, with the links in a dummy first entry of + each table. */ +{ + register inflate_huft *p, *q; + + /* Go through linked list, freeing from the malloced (t[-1]) address. */ + p = t; + while (p != Z_NULL) + { + q = (--p)->next; + ZFREE(z, p, p->word.Nalloc * sizeof(inflate_huft)); + p = q; + } + return Z_OK; +} + +/*+++++*/ +/* infcodes.c -- process literals and length/distance pairs + * Copyright (C) 1995 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* simplify the use of the inflate_huft type with some defines */ +#define base more.Base +#define next more.Next +#define exop word.what.Exop +#define bits word.what.Bits + +/* inflate codes private state */ +struct inflate_codes_state { + + /* mode */ + enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */ + START, /* x: set up for LEN */ + LEN, /* i: get length/literal/eob next */ + LENEXT, /* i: getting length extra (have base) */ + DIST, /* i: get distance next */ + DISTEXT, /* i: getting distance extra */ + COPY, /* o: copying bytes in window, waiting for space */ + LIT, /* o: got literal, waiting for output space */ + WASH, /* o: got eob, possibly still output waiting */ + END, /* x: got eob and all data flushed */ + BADCODE} /* x: got error */ + mode; /* current inflate_codes mode */ + + /* mode dependent information */ + uInt len; + union { + struct { + inflate_huft *tree; /* pointer into tree */ + uInt need; /* bits needed */ + } code; /* if LEN or DIST, where in tree */ + uInt lit; /* if LIT, literal */ + struct { + uInt get; /* bits to get for extra */ + uInt dist; /* distance back to copy from */ + } copy; /* if EXT or COPY, where and how much */ + } sub; /* submode */ + + /* mode independent information */ + Byte lbits; /* ltree bits decoded per branch */ + Byte dbits; /* dtree bits decoder per branch */ + inflate_huft *ltree; /* literal/length/eob tree */ + inflate_huft *dtree; /* distance tree */ + +}; + + +local inflate_codes_statef *inflate_codes_new(bl, bd, tl, td, z) +uInt bl, bd; +inflate_huft *tl, *td; +z_stream *z; +{ + inflate_codes_statef *c; + + if ((c = (inflate_codes_statef *) + ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL) + { + c->mode = START; + c->lbits = (Byte)bl; + c->dbits = (Byte)bd; + c->ltree = tl; + c->dtree = td; + Tracev((stderr, "inflate: codes new\n")); + } + return c; +} + + +local int inflate_codes(s, z, r) +inflate_blocks_statef *s; +z_stream *z; +int r; +{ + uInt j; /* temporary storage */ + inflate_huft *t; /* temporary pointer */ + uInt e; /* extra bits or operation */ + uLong b; /* bit buffer */ + uInt k; /* bits in bit buffer */ + Bytef *p; /* input data pointer */ + uInt n; /* bytes available there */ + Bytef *q; /* output window write pointer */ + uInt m; /* bytes to end of window or read pointer */ + Bytef *f; /* pointer to copy strings from */ + inflate_codes_statef *c = s->sub.decode.codes; /* codes state */ + + /* copy input/output information to locals (UPDATE macro restores) */ + LOAD + + /* process input and output based on current state */ + while (1) switch (c->mode) + { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */ + case START: /* x: set up for LEN */ +#ifndef SLOW + if (m >= 258 && n >= 10) + { + UPDATE + r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z); + LOAD + if (r != Z_OK) + { + c->mode = r == Z_STREAM_END ? WASH : BADCODE; + break; + } + } +#endif /* !SLOW */ + c->sub.code.need = c->lbits; + c->sub.code.tree = c->ltree; + c->mode = LEN; + case LEN: /* i: get length/literal/eob next */ + j = c->sub.code.need; + NEEDBITS(j) + t = c->sub.code.tree + ((uInt)b & inflate_mask[j]); + DUMPBITS(t->bits) + e = (uInt)(t->exop); + if (e == 0) /* literal */ + { + c->sub.lit = t->base; + Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ? + "inflate: literal '%c'\n" : + "inflate: literal 0x%02x\n", t->base)); + c->mode = LIT; + break; + } + if (e & 16) /* length */ + { + c->sub.copy.get = e & 15; + c->len = t->base; + c->mode = LENEXT; + break; + } + if ((e & 64) == 0) /* next table */ + { + c->sub.code.need = e; + c->sub.code.tree = t->next; + break; + } + if (e & 32) /* end of block */ + { + Tracevv((stderr, "inflate: end of block\n")); + c->mode = WASH; + break; + } + c->mode = BADCODE; /* invalid code */ + z->msg = "invalid literal/length code"; + r = Z_DATA_ERROR; + LEAVE + case LENEXT: /* i: getting length extra (have base) */ + j = c->sub.copy.get; + NEEDBITS(j) + c->len += (uInt)b & inflate_mask[j]; + DUMPBITS(j) + c->sub.code.need = c->dbits; + c->sub.code.tree = c->dtree; + Tracevv((stderr, "inflate: length %u\n", c->len)); + c->mode = DIST; + case DIST: /* i: get distance next */ + j = c->sub.code.need; + NEEDBITS(j) + t = c->sub.code.tree + ((uInt)b & inflate_mask[j]); + DUMPBITS(t->bits) + e = (uInt)(t->exop); + if (e & 16) /* distance */ + { + c->sub.copy.get = e & 15; + c->sub.copy.dist = t->base; + c->mode = DISTEXT; + break; + } + if ((e & 64) == 0) /* next table */ + { + c->sub.code.need = e; + c->sub.code.tree = t->next; + break; + } + c->mode = BADCODE; /* invalid code */ + z->msg = "invalid distance code"; + r = Z_DATA_ERROR; + LEAVE + case DISTEXT: /* i: getting distance extra */ + j = c->sub.copy.get; + NEEDBITS(j) + c->sub.copy.dist += (uInt)b & inflate_mask[j]; + DUMPBITS(j) + Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist)); + c->mode = COPY; + case COPY: /* o: copying bytes in window, waiting for space */ +#ifndef __TURBOC__ /* Turbo C bug for following expression */ + f = (uInt)(q - s->window) < c->sub.copy.dist ? + s->end - (c->sub.copy.dist - (q - s->window)) : + q - c->sub.copy.dist; +#else + f = q - c->sub.copy.dist; + if ((uInt)(q - s->window) < c->sub.copy.dist) + f = s->end - (c->sub.copy.dist - (q - s->window)); +#endif + while (c->len) + { + NEEDOUT + OUTBYTE(*f++) + if (f == s->end) + f = s->window; + c->len--; + } + c->mode = START; + break; + case LIT: /* o: got literal, waiting for output space */ + NEEDOUT + OUTBYTE(c->sub.lit) + c->mode = START; + break; + case WASH: /* o: got eob, possibly more output */ + FLUSH + if (s->read != s->write) + LEAVE + c->mode = END; + case END: + r = Z_STREAM_END; + LEAVE + case BADCODE: /* x: got error */ + r = Z_DATA_ERROR; + LEAVE + default: + r = Z_STREAM_ERROR; + LEAVE + } +} + + +local void inflate_codes_free(c, z) +inflate_codes_statef *c; +z_stream *z; +{ + ZFREE(z, c, sizeof(struct inflate_codes_state)); + Tracev((stderr, "inflate: codes free\n")); +} + +/*+++++*/ +/* inflate_util.c -- data and routines common to blocks and codes + * Copyright (C) 1995 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* copy as much as possible from the sliding window to the output area */ +local int inflate_flush(s, z, r) +inflate_blocks_statef *s; +z_stream *z; +int r; +{ + uInt n; + Bytef *p, *q; + + /* local copies of source and destination pointers */ + p = z->next_out; + q = s->read; + + /* compute number of bytes to copy as far as end of window */ + n = (uInt)((q <= s->write ? s->write : s->end) - q); + if (n > z->avail_out) n = z->avail_out; + if (n && r == Z_BUF_ERROR) r = Z_OK; + + /* update counters */ + z->avail_out -= n; + z->total_out += n; + + /* update check information */ + if (s->checkfn != Z_NULL) + s->check = (*s->checkfn)(s->check, q, n); + + /* copy as far as end of window */ + if (p != NULL) { + zmemcpy(p, q, n); + p += n; + } + q += n; + + /* see if more to copy at beginning of window */ + if (q == s->end) + { + /* wrap pointers */ + q = s->window; + if (s->write == s->end) + s->write = s->window; + + /* compute bytes to copy */ + n = (uInt)(s->write - q); + if (n > z->avail_out) n = z->avail_out; + if (n && r == Z_BUF_ERROR) r = Z_OK; + + /* update counters */ + z->avail_out -= n; + z->total_out += n; + + /* update check information */ + if (s->checkfn != Z_NULL) + s->check = (*s->checkfn)(s->check, q, n); + + /* copy */ + if (p != NULL) { + zmemcpy(p, q, n); + p += n; + } + q += n; + } + + /* update pointers */ + z->next_out = p; + s->read = q; + + /* done */ + return r; +} + + +/*+++++*/ +/* inffast.c -- process literals and length/distance pairs fast + * Copyright (C) 1995 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* simplify the use of the inflate_huft type with some defines */ +#define base more.Base +#define next more.Next +#define exop word.what.Exop +#define bits word.what.Bits + +/* macros for bit input with no checking and for returning unused bytes */ +#define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}} +#define UNGRAB {n+=(c=k>>3);p-=c;k&=7;} + +/* Called with number of bytes left to write in window at least 258 + (the maximum string length) and number of input bytes available + at least ten. The ten bytes are six bytes for the longest length/ + distance pair plus four bytes for overloading the bit buffer. */ + +local int inflate_fast(bl, bd, tl, td, s, z) +uInt bl, bd; +inflate_huft *tl, *td; +inflate_blocks_statef *s; +z_stream *z; +{ + inflate_huft *t; /* temporary pointer */ + uInt e; /* extra bits or operation */ + uLong b; /* bit buffer */ + uInt k; /* bits in bit buffer */ + Bytef *p; /* input data pointer */ + uInt n; /* bytes available there */ + Bytef *q; /* output window write pointer */ + uInt m; /* bytes to end of window or read pointer */ + uInt ml; /* mask for literal/length tree */ + uInt md; /* mask for distance tree */ + uInt c; /* bytes to copy */ + uInt d; /* distance back to copy from */ + Bytef *r; /* copy source pointer */ + + /* load input, output, bit values */ + LOAD + + /* initialize masks */ + ml = inflate_mask[bl]; + md = inflate_mask[bd]; + + /* do until not enough input or output space for fast loop */ + do { /* assume called with m >= 258 && n >= 10 */ + /* get literal/length code */ + GRABBITS(20) /* max bits for literal/length code */ + if ((e = (t = tl + ((uInt)b & ml))->exop) == 0) + { + DUMPBITS(t->bits) + Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ? + "inflate: * literal '%c'\n" : + "inflate: * literal 0x%02x\n", t->base)); + *q++ = (Byte)t->base; + m--; + continue; + } + do { + DUMPBITS(t->bits) + if (e & 16) + { + /* get extra bits for length */ + e &= 15; + c = t->base + ((uInt)b & inflate_mask[e]); + DUMPBITS(e) + Tracevv((stderr, "inflate: * length %u\n", c)); + + /* decode distance base of block to copy */ + GRABBITS(15); /* max bits for distance code */ + e = (t = td + ((uInt)b & md))->exop; + do { + DUMPBITS(t->bits) + if (e & 16) + { + /* get extra bits to add to distance base */ + e &= 15; + GRABBITS(e) /* get extra bits (up to 13) */ + d = t->base + ((uInt)b & inflate_mask[e]); + DUMPBITS(e) + Tracevv((stderr, "inflate: * distance %u\n", d)); + + /* do the copy */ + m -= c; + if ((uInt)(q - s->window) >= d) /* offset before dest */ + { /* just copy */ + r = q - d; + *q++ = *r++; c--; /* minimum count is three, */ + *q++ = *r++; c--; /* so unroll loop a little */ + } + else /* else offset after destination */ + { + e = d - (q - s->window); /* bytes from offset to end */ + r = s->end - e; /* pointer to offset */ + if (c > e) /* if source crosses, */ + { + c -= e; /* copy to end of window */ + do { + *q++ = *r++; + } while (--e); + r = s->window; /* copy rest from start of window */ + } + } + do { /* copy all or what's left */ + *q++ = *r++; + } while (--c); + break; + } + else if ((e & 64) == 0) + e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop; + else + { + z->msg = "invalid distance code"; + UNGRAB + UPDATE + return Z_DATA_ERROR; + } + } while (1); + break; + } + if ((e & 64) == 0) + { + if ((e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop) == 0) + { + DUMPBITS(t->bits) + Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ? + "inflate: * literal '%c'\n" : + "inflate: * literal 0x%02x\n", t->base)); + *q++ = (Byte)t->base; + m--; + break; + } + } + else if (e & 32) + { + Tracevv((stderr, "inflate: * end of block\n")); + UNGRAB + UPDATE + return Z_STREAM_END; + } + else + { + z->msg = "invalid literal/length code"; + UNGRAB + UPDATE + return Z_DATA_ERROR; + } + } while (1); + } while (m >= 258 && n >= 10); + + /* not enough input or output--restore pointers and return */ + UNGRAB + UPDATE + return Z_OK; +} + + +/*+++++*/ +/* zutil.c -- target dependent utility functions for the compression library + * Copyright (C) 1995 Jean-loup Gailly. + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* From: zutil.c,v 1.8 1995/05/03 17:27:12 jloup Exp */ + +char *zlib_version = ZLIB_VERSION; + +char *z_errmsg[] = { +"stream end", /* Z_STREAM_END 1 */ +"", /* Z_OK 0 */ +"file error", /* Z_ERRNO (-1) */ +"stream error", /* Z_STREAM_ERROR (-2) */ +"data error", /* Z_DATA_ERROR (-3) */ +"insufficient memory", /* Z_MEM_ERROR (-4) */ +"buffer error", /* Z_BUF_ERROR (-5) */ +""}; + + +/*+++++*/ +/* adler32.c -- compute the Adler-32 checksum of a data stream + * Copyright (C) 1995 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* From: adler32.c,v 1.6 1995/05/03 17:27:08 jloup Exp */ + +#define BASE 65521L /* largest prime smaller than 65536 */ +#define NMAX 5552 +/* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */ + +#define DO1(buf) {s1 += *buf++; s2 += s1;} +#define DO2(buf) DO1(buf); DO1(buf); +#define DO4(buf) DO2(buf); DO2(buf); +#define DO8(buf) DO4(buf); DO4(buf); +#define DO16(buf) DO8(buf); DO8(buf); + +/* ========================================================================= */ +uLong adler32(adler, buf, len) + uLong adler; + Bytef *buf; + uInt len; +{ + unsigned long s1 = adler & 0xffff; + unsigned long s2 = (adler >> 16) & 0xffff; + int k; + + if (buf == Z_NULL) return 1L; + + while (len > 0) { + k = len < NMAX ? len : NMAX; + len -= k; + while (k >= 16) { + DO16(buf); + k -= 16; + } + if (k != 0) do { + DO1(buf); + } while (--k); + s1 %= BASE; + s2 %= BASE; + } + return (s2 << 16) | s1; +} |
