wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1 | /* |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 2 | * This file is derived from various .h and .c files from the zlib-1.2.3 |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 3 | * distribution by Jean-loup Gailly and Mark Adler, with some additions |
| 4 | * by Paul Mackerras to aid in implementing Deflate compression and |
| 5 | * decompression for PPP packets. See zlib.h for conditions of |
| 6 | * distribution and use. |
| 7 | * |
| 8 | * Changes that have been made include: |
| 9 | * - changed functions not used outside this file to "local" |
| 10 | * - added minCompression parameter to deflateInit2 |
| 11 | * - added Z_PACKET_FLUSH (see zlib.h for details) |
| 12 | * - added inflateIncomp |
| 13 | */ |
| 14 | |
| 15 | /*+++++*/ |
| 16 | /* zutil.h -- internal interface and configuration of the compression library |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 17 | * Copyright (C) 1995-2005 Jean-loup Gailly. |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 18 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 19 | */ |
| 20 | |
| 21 | /* WARNING: this file should *not* be used by applications. It is |
| 22 | part of the implementation of the compression library and is |
| 23 | subject to change. Applications should only use zlib.h. |
| 24 | */ |
| 25 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 26 | #define ZUTIL_H |
| 27 | #define ZLIB_INTERNAL |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 28 | |
Jean-Christophe PLAGNIOL-VILLARD | 6bb9449 | 2009-04-04 12:49:11 +0200 | [diff] [blame] | 29 | #include "u-boot/zlib.h" |
Giuseppe CONDORELLI | 9041654 | 2009-09-03 07:37:46 -0400 | [diff] [blame] | 30 | #include <common.h> |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 31 | /* To avoid a build time warning */ |
| 32 | #ifdef STDC |
| 33 | #include <malloc.h> |
| 34 | #endif |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 35 | |
| 36 | #ifndef local |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 37 | #define local static |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 38 | #endif |
| 39 | /* compile with -Dlocal if your debugger can't find static symbols */ |
| 40 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 41 | typedef unsigned char uch; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 42 | typedef uch FAR uchf; |
| 43 | typedef unsigned short ush; |
| 44 | typedef ush FAR ushf; |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 45 | typedef unsigned long ulg; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 46 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 47 | #define ERR_MSG(err) z_errmsg[Z_NEED_DICT-(err)] |
| 48 | #define ERR_RETURN(strm,err) return (strm->msg = (char*)ERR_MSG(err), (err)) |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 49 | /* To be used only when the state is known to be valid */ |
| 50 | |
| 51 | #ifndef NULL |
| 52 | #define NULL ((void *) 0) |
| 53 | #endif |
| 54 | |
wdenk | 57b2d80 | 2003-06-27 21:31:46 +0000 | [diff] [blame] | 55 | /* common constants */ |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 56 | |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 57 | #ifndef DEF_WBITS |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 58 | #define DEF_WBITS MAX_WBITS |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 59 | #endif |
| 60 | /* default windowBits for decompression. MAX_WBITS is for compression only */ |
| 61 | |
| 62 | #if MAX_MEM_LEVEL >= 8 |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 63 | #define DEF_MEM_LEVEL 8 |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 64 | #else |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 65 | #define DEF_MEM_LEVEL MAX_MEM_LEVEL |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 66 | #endif |
| 67 | /* default memLevel */ |
| 68 | |
| 69 | #define STORED_BLOCK 0 |
| 70 | #define STATIC_TREES 1 |
| 71 | #define DYN_TREES 2 |
| 72 | /* The three kinds of block type */ |
| 73 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 74 | #define MIN_MATCH 3 |
| 75 | #define MAX_MATCH 258 |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 76 | /* The minimum and maximum match lengths */ |
| 77 | |
wdenk | 57b2d80 | 2003-06-27 21:31:46 +0000 | [diff] [blame] | 78 | /* functions */ |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 79 | |
| 80 | #include <linux/string.h> |
| 81 | #define zmemcpy memcpy |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 82 | #define zmemcmp memcmp |
| 83 | #define zmemzero(dest, len) memset(dest, 0, len) |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 84 | |
| 85 | /* Diagnostic functions */ |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 86 | #ifdef DEBUG |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 87 | extern int z_verbose; |
| 88 | extern void z_error OF((char *m)); |
| 89 | #define Assert(cond,msg) {if(!(cond)) z_error(msg);} |
Giuseppe CONDORELLI | 9041654 | 2009-09-03 07:37:46 -0400 | [diff] [blame] | 90 | #define fprintf(fp,...) printf(__VA_ARGS__) |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 91 | #define Trace(x) {if (z_verbose>=0) fprintf x ;} |
| 92 | #define Tracev(x) {if (z_verbose>0) fprintf x ;} |
| 93 | #define Tracevv(x) {if (z_verbose>1) fprintf x ;} |
| 94 | #define Tracec(c,x) {if (z_verbose>0 && (c)) fprintf x ;} |
| 95 | #define Tracecv(c,x) {if (z_verbose>1 && (c)) fprintf x ;} |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 96 | #else |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 97 | #define Assert(cond,msg) |
| 98 | #define Trace(x) |
| 99 | #define Tracev(x) |
| 100 | #define Tracevv(x) |
| 101 | #define Tracec(c,x) |
| 102 | #define Tracecv(c,x) |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 103 | #endif |
| 104 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 105 | voidpf zcalloc OF((voidpf opaque, unsigned items, unsigned size)); |
| 106 | void zcfree OF((voidpf opaque, voidpf ptr, unsigned size)); |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 107 | |
| 108 | #define ZALLOC(strm, items, size) \ |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 109 | (*((strm)->zalloc))((strm)->opaque, (items), (size)) |
| 110 | #define ZFREE(strm, addr) (*((strm)->zfree))((strm)->opaque, (voidpf)(addr), 0) |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 111 | |
| 112 | /*+++++*/ |
| 113 | /* inftrees.h -- header to use inftrees.c |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 114 | * Copyright (C) 1995-2005 Mark Adler |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 115 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 116 | */ |
| 117 | |
| 118 | /* WARNING: this file should *not* be used by applications. It is |
| 119 | part of the implementation of the compression library and is |
| 120 | subject to change. Applications should only use zlib.h. |
| 121 | */ |
| 122 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 123 | /* Structure for decoding tables. Each entry provides either the |
| 124 | information needed to do the operation requested by the code that |
| 125 | indexed that table entry, or it provides a pointer to another |
| 126 | table that indexes more bits of the code. op indicates whether |
| 127 | the entry is a pointer to another table, a literal, a length or |
| 128 | distance, an end-of-block, or an invalid code. For a table |
| 129 | pointer, the low four bits of op is the number of index bits of |
| 130 | that table. For a length or distance, the low four bits of op |
| 131 | is the number of extra bits to get after the code. bits is |
| 132 | the number of bits in this code or part of the code to drop off |
| 133 | of the bit buffer. val is the actual byte to output in the case |
| 134 | of a literal, the base length or distance, or the offset from |
| 135 | the current table to the next table. Each entry is four bytes. */ |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 136 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 137 | typedef struct { |
| 138 | unsigned char op; /* operation, extra bits, table bits */ |
| 139 | unsigned char bits; /* bits in this part of the code */ |
| 140 | unsigned short val; /* offset in table or code value */ |
| 141 | } code; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 142 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 143 | /* Maximum size of dynamic tree. The maximum found in a long but non- |
| 144 | exhaustive search was 1444 code structures (852 for length/literals |
| 145 | and 592 for distances, the latter actually the result of an |
| 146 | exhaustive search). The true maximum is not known, but the value |
| 147 | below is more than safe. */ |
| 148 | #define ENOUGH 2048 |
| 149 | #define MAXD 592 |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 150 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 151 | /* Type of code to build for inftable() */ |
| 152 | typedef enum { |
| 153 | CODES, |
| 154 | LENS, |
| 155 | DISTS |
| 156 | } codetype; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 157 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 158 | extern int inflate_table OF((codetype type, unsigned short FAR *lens, |
| 159 | unsigned codes, code FAR * FAR *table, |
| 160 | unsigned FAR *bits, unsigned short FAR *work)); |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 161 | /*+++++*/ |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 162 | /* inflate.h -- internal inflate state definition |
| 163 | * Copyright (C) 1995-2004 Mark Adler |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 164 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 165 | */ |
| 166 | |
| 167 | /* WARNING: this file should *not* be used by applications. It is |
| 168 | part of the implementation of the compression library and is |
| 169 | subject to change. Applications should only use zlib.h. |
| 170 | */ |
| 171 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 172 | #define GUNZIP |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 173 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 174 | /* Possible inflate modes between inflate() calls */ |
| 175 | typedef enum { |
| 176 | HEAD, /* i: waiting for magic header */ |
| 177 | FLAGS, /* i: waiting for method and flags (gzip) */ |
| 178 | TIME, /* i: waiting for modification time (gzip) */ |
| 179 | OS, /* i: waiting for extra flags and operating system (gzip) */ |
| 180 | EXLEN, /* i: waiting for extra length (gzip) */ |
| 181 | EXTRA, /* i: waiting for extra bytes (gzip) */ |
| 182 | NAME, /* i: waiting for end of file name (gzip) */ |
| 183 | COMMENT, /* i: waiting for end of comment (gzip) */ |
| 184 | HCRC, /* i: waiting for header crc (gzip) */ |
| 185 | DICTID, /* i: waiting for dictionary check value */ |
| 186 | DICT, /* waiting for inflateSetDictionary() call */ |
| 187 | TYPE, /* i: waiting for type bits, including last-flag bit */ |
| 188 | TYPEDO, /* i: same, but skip check to exit inflate on new block */ |
| 189 | STORED, /* i: waiting for stored size (length and complement) */ |
| 190 | COPY, /* i/o: waiting for input or output to copy stored block */ |
| 191 | TABLE, /* i: waiting for dynamic block table lengths */ |
| 192 | LENLENS, /* i: waiting for code length code lengths */ |
| 193 | CODELENS, /* i: waiting for length/lit and distance code lengths */ |
| 194 | LEN, /* i: waiting for length/lit code */ |
| 195 | LENEXT, /* i: waiting for length extra bits */ |
| 196 | DIST, /* i: waiting for distance code */ |
| 197 | DISTEXT, /* i: waiting for distance extra bits */ |
| 198 | MATCH, /* o: waiting for output space to copy string */ |
| 199 | LIT, /* o: waiting for output space to write literal */ |
| 200 | CHECK, /* i: waiting for 32-bit check value */ |
| 201 | LENGTH, /* i: waiting for 32-bit length (gzip) */ |
| 202 | DONE, /* finished check, done -- remain here until reset */ |
| 203 | BAD, /* got a data error -- remain here until reset */ |
| 204 | MEM, /* got an inflate() memory error -- remain here until reset */ |
| 205 | SYNC, /* looking for synchronization bytes to restart inflate() */ |
| 206 | START, |
| 207 | WASH, |
| 208 | END, |
| 209 | BADCODE |
| 210 | } inflate_mode; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 211 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 212 | /* |
| 213 | State transitions between above modes - |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 214 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 215 | (most modes can go to the BAD or MEM mode -- not shown for clarity) |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 216 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 217 | Process header: |
| 218 | HEAD -> (gzip) or (zlib) |
| 219 | (gzip) -> FLAGS -> TIME -> OS -> EXLEN -> EXTRA -> NAME |
| 220 | NAME -> COMMENT -> HCRC -> TYPE |
| 221 | (zlib) -> DICTID or TYPE |
| 222 | DICTID -> DICT -> TYPE |
| 223 | Read deflate blocks: |
| 224 | TYPE -> STORED or TABLE or LEN or CHECK |
| 225 | STORED -> COPY -> TYPE |
| 226 | TABLE -> LENLENS -> CODELENS -> LEN |
| 227 | Read deflate codes: |
| 228 | LEN -> LENEXT or LIT or TYPE |
| 229 | LENEXT -> DIST -> DISTEXT -> MATCH -> LEN |
| 230 | LIT -> LEN |
| 231 | Process trailer: |
| 232 | CHECK -> LENGTH -> DONE |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 233 | */ |
| 234 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 235 | /* state maintained between inflate() calls. Approximately 7K bytes. */ |
| 236 | struct inflate_state { |
| 237 | inflate_mode mode; /* current inflate mode */ |
| 238 | int last; /* true if processing last block */ |
| 239 | int wrap; /* bit 0 true for zlib, bit 1 true for gzip */ |
| 240 | int havedict; /* true if dictionary provided */ |
| 241 | int flags; /* gzip header method and flags (0 if zlib) */ |
| 242 | unsigned dmax; /* zlib header max distance (INFLATE_STRICT) */ |
| 243 | unsigned long check; /* protected copy of check value */ |
| 244 | unsigned long total; /* protected copy of output count */ |
| 245 | gz_headerp head; /* where to save gzip header information */ |
| 246 | /* sliding window */ |
| 247 | unsigned wbits; /* log base 2 of requested window size */ |
| 248 | unsigned wsize; /* window size or zero if not using window */ |
| 249 | unsigned whave; /* valid bytes in the window */ |
| 250 | unsigned write; /* window write index */ |
| 251 | unsigned char FAR *window; /* allocated sliding window, if needed */ |
| 252 | /* bit accumulator */ |
| 253 | unsigned long hold; /* input bit accumulator */ |
| 254 | unsigned bits; /* number of bits in "in" */ |
| 255 | /* for string and stored block copying */ |
| 256 | unsigned length; /* literal or length of data to copy */ |
| 257 | unsigned offset; /* distance back to copy string from */ |
| 258 | /* for table and code decoding */ |
| 259 | unsigned extra; /* extra bits needed */ |
| 260 | /* fixed and dynamic code tables */ |
| 261 | code const FAR *lencode; /* starting table for length/literal codes */ |
| 262 | code const FAR *distcode; /* starting table for distance codes */ |
| 263 | unsigned lenbits; /* index bits for lencode */ |
| 264 | unsigned distbits; /* index bits for distcode */ |
| 265 | /* dynamic table building */ |
| 266 | unsigned ncode; /* number of code length code lengths */ |
| 267 | unsigned nlen; /* number of length code lengths */ |
| 268 | unsigned ndist; /* number of distance code lengths */ |
| 269 | unsigned have; /* number of code lengths in lens[] */ |
| 270 | code FAR *next; /* next available space in codes[] */ |
| 271 | unsigned short lens[320]; /* temporary storage for code lengths */ |
| 272 | unsigned short work[288]; /* work area for code table building */ |
| 273 | code codes[ENOUGH]; /* space for code tables */ |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 274 | }; |
| 275 | |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 276 | /*+++++*/ |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 277 | /* inffast.h -- header to use inffast.c |
| 278 | * Copyright (C) 1995-2003 Mark Adler |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 279 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 280 | */ |
| 281 | |
| 282 | /* WARNING: this file should *not* be used by applications. It is |
| 283 | part of the implementation of the compression library and is |
| 284 | subject to change. Applications should only use zlib.h. |
| 285 | */ |
| 286 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 287 | void inflate_fast OF((z_streamp strm, unsigned start)); |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 288 | /*+++++*/ |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 289 | /* inffixed.h -- table for decoding fixed codes |
| 290 | * Generated automatically by makefixed(). |
| 291 | */ |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 292 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 293 | /* WARNING: this file should *not* be used by applications. It |
| 294 | is part of the implementation of the compression library and |
| 295 | is subject to change. Applications should only use zlib.h. |
| 296 | */ |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 297 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 298 | static const code lenfix[512] = { |
| 299 | {96,7,0},{0,8,80},{0,8,16},{20,8,115},{18,7,31},{0,8,112},{0,8,48}, |
| 300 | {0,9,192},{16,7,10},{0,8,96},{0,8,32},{0,9,160},{0,8,0},{0,8,128}, |
| 301 | {0,8,64},{0,9,224},{16,7,6},{0,8,88},{0,8,24},{0,9,144},{19,7,59}, |
| 302 | {0,8,120},{0,8,56},{0,9,208},{17,7,17},{0,8,104},{0,8,40},{0,9,176}, |
| 303 | {0,8,8},{0,8,136},{0,8,72},{0,9,240},{16,7,4},{0,8,84},{0,8,20}, |
| 304 | {21,8,227},{19,7,43},{0,8,116},{0,8,52},{0,9,200},{17,7,13},{0,8,100}, |
| 305 | {0,8,36},{0,9,168},{0,8,4},{0,8,132},{0,8,68},{0,9,232},{16,7,8}, |
| 306 | {0,8,92},{0,8,28},{0,9,152},{20,7,83},{0,8,124},{0,8,60},{0,9,216}, |
| 307 | {18,7,23},{0,8,108},{0,8,44},{0,9,184},{0,8,12},{0,8,140},{0,8,76}, |
| 308 | {0,9,248},{16,7,3},{0,8,82},{0,8,18},{21,8,163},{19,7,35},{0,8,114}, |
| 309 | {0,8,50},{0,9,196},{17,7,11},{0,8,98},{0,8,34},{0,9,164},{0,8,2}, |
| 310 | {0,8,130},{0,8,66},{0,9,228},{16,7,7},{0,8,90},{0,8,26},{0,9,148}, |
| 311 | {20,7,67},{0,8,122},{0,8,58},{0,9,212},{18,7,19},{0,8,106},{0,8,42}, |
| 312 | {0,9,180},{0,8,10},{0,8,138},{0,8,74},{0,9,244},{16,7,5},{0,8,86}, |
| 313 | {0,8,22},{64,8,0},{19,7,51},{0,8,118},{0,8,54},{0,9,204},{17,7,15}, |
| 314 | {0,8,102},{0,8,38},{0,9,172},{0,8,6},{0,8,134},{0,8,70},{0,9,236}, |
| 315 | {16,7,9},{0,8,94},{0,8,30},{0,9,156},{20,7,99},{0,8,126},{0,8,62}, |
| 316 | {0,9,220},{18,7,27},{0,8,110},{0,8,46},{0,9,188},{0,8,14},{0,8,142}, |
| 317 | {0,8,78},{0,9,252},{96,7,0},{0,8,81},{0,8,17},{21,8,131},{18,7,31}, |
| 318 | {0,8,113},{0,8,49},{0,9,194},{16,7,10},{0,8,97},{0,8,33},{0,9,162}, |
| 319 | {0,8,1},{0,8,129},{0,8,65},{0,9,226},{16,7,6},{0,8,89},{0,8,25}, |
| 320 | {0,9,146},{19,7,59},{0,8,121},{0,8,57},{0,9,210},{17,7,17},{0,8,105}, |
| 321 | {0,8,41},{0,9,178},{0,8,9},{0,8,137},{0,8,73},{0,9,242},{16,7,4}, |
| 322 | {0,8,85},{0,8,21},{16,8,258},{19,7,43},{0,8,117},{0,8,53},{0,9,202}, |
| 323 | {17,7,13},{0,8,101},{0,8,37},{0,9,170},{0,8,5},{0,8,133},{0,8,69}, |
| 324 | {0,9,234},{16,7,8},{0,8,93},{0,8,29},{0,9,154},{20,7,83},{0,8,125}, |
| 325 | {0,8,61},{0,9,218},{18,7,23},{0,8,109},{0,8,45},{0,9,186},{0,8,13}, |
| 326 | {0,8,141},{0,8,77},{0,9,250},{16,7,3},{0,8,83},{0,8,19},{21,8,195}, |
| 327 | {19,7,35},{0,8,115},{0,8,51},{0,9,198},{17,7,11},{0,8,99},{0,8,35}, |
| 328 | {0,9,166},{0,8,3},{0,8,131},{0,8,67},{0,9,230},{16,7,7},{0,8,91}, |
| 329 | {0,8,27},{0,9,150},{20,7,67},{0,8,123},{0,8,59},{0,9,214},{18,7,19}, |
| 330 | {0,8,107},{0,8,43},{0,9,182},{0,8,11},{0,8,139},{0,8,75},{0,9,246}, |
| 331 | {16,7,5},{0,8,87},{0,8,23},{64,8,0},{19,7,51},{0,8,119},{0,8,55}, |
| 332 | {0,9,206},{17,7,15},{0,8,103},{0,8,39},{0,9,174},{0,8,7},{0,8,135}, |
| 333 | {0,8,71},{0,9,238},{16,7,9},{0,8,95},{0,8,31},{0,9,158},{20,7,99}, |
| 334 | {0,8,127},{0,8,63},{0,9,222},{18,7,27},{0,8,111},{0,8,47},{0,9,190}, |
| 335 | {0,8,15},{0,8,143},{0,8,79},{0,9,254},{96,7,0},{0,8,80},{0,8,16}, |
| 336 | {20,8,115},{18,7,31},{0,8,112},{0,8,48},{0,9,193},{16,7,10},{0,8,96}, |
| 337 | {0,8,32},{0,9,161},{0,8,0},{0,8,128},{0,8,64},{0,9,225},{16,7,6}, |
| 338 | {0,8,88},{0,8,24},{0,9,145},{19,7,59},{0,8,120},{0,8,56},{0,9,209}, |
| 339 | {17,7,17},{0,8,104},{0,8,40},{0,9,177},{0,8,8},{0,8,136},{0,8,72}, |
| 340 | {0,9,241},{16,7,4},{0,8,84},{0,8,20},{21,8,227},{19,7,43},{0,8,116}, |
| 341 | {0,8,52},{0,9,201},{17,7,13},{0,8,100},{0,8,36},{0,9,169},{0,8,4}, |
| 342 | {0,8,132},{0,8,68},{0,9,233},{16,7,8},{0,8,92},{0,8,28},{0,9,153}, |
| 343 | {20,7,83},{0,8,124},{0,8,60},{0,9,217},{18,7,23},{0,8,108},{0,8,44}, |
| 344 | {0,9,185},{0,8,12},{0,8,140},{0,8,76},{0,9,249},{16,7,3},{0,8,82}, |
| 345 | {0,8,18},{21,8,163},{19,7,35},{0,8,114},{0,8,50},{0,9,197},{17,7,11}, |
| 346 | {0,8,98},{0,8,34},{0,9,165},{0,8,2},{0,8,130},{0,8,66},{0,9,229}, |
| 347 | {16,7,7},{0,8,90},{0,8,26},{0,9,149},{20,7,67},{0,8,122},{0,8,58}, |
| 348 | {0,9,213},{18,7,19},{0,8,106},{0,8,42},{0,9,181},{0,8,10},{0,8,138}, |
| 349 | {0,8,74},{0,9,245},{16,7,5},{0,8,86},{0,8,22},{64,8,0},{19,7,51}, |
| 350 | {0,8,118},{0,8,54},{0,9,205},{17,7,15},{0,8,102},{0,8,38},{0,9,173}, |
| 351 | {0,8,6},{0,8,134},{0,8,70},{0,9,237},{16,7,9},{0,8,94},{0,8,30}, |
| 352 | {0,9,157},{20,7,99},{0,8,126},{0,8,62},{0,9,221},{18,7,27},{0,8,110}, |
| 353 | {0,8,46},{0,9,189},{0,8,14},{0,8,142},{0,8,78},{0,9,253},{96,7,0}, |
| 354 | {0,8,81},{0,8,17},{21,8,131},{18,7,31},{0,8,113},{0,8,49},{0,9,195}, |
| 355 | {16,7,10},{0,8,97},{0,8,33},{0,9,163},{0,8,1},{0,8,129},{0,8,65}, |
| 356 | {0,9,227},{16,7,6},{0,8,89},{0,8,25},{0,9,147},{19,7,59},{0,8,121}, |
| 357 | {0,8,57},{0,9,211},{17,7,17},{0,8,105},{0,8,41},{0,9,179},{0,8,9}, |
| 358 | {0,8,137},{0,8,73},{0,9,243},{16,7,4},{0,8,85},{0,8,21},{16,8,258}, |
| 359 | {19,7,43},{0,8,117},{0,8,53},{0,9,203},{17,7,13},{0,8,101},{0,8,37}, |
| 360 | {0,9,171},{0,8,5},{0,8,133},{0,8,69},{0,9,235},{16,7,8},{0,8,93}, |
| 361 | {0,8,29},{0,9,155},{20,7,83},{0,8,125},{0,8,61},{0,9,219},{18,7,23}, |
| 362 | {0,8,109},{0,8,45},{0,9,187},{0,8,13},{0,8,141},{0,8,77},{0,9,251}, |
| 363 | {16,7,3},{0,8,83},{0,8,19},{21,8,195},{19,7,35},{0,8,115},{0,8,51}, |
| 364 | {0,9,199},{17,7,11},{0,8,99},{0,8,35},{0,9,167},{0,8,3},{0,8,131}, |
| 365 | {0,8,67},{0,9,231},{16,7,7},{0,8,91},{0,8,27},{0,9,151},{20,7,67}, |
| 366 | {0,8,123},{0,8,59},{0,9,215},{18,7,19},{0,8,107},{0,8,43},{0,9,183}, |
| 367 | {0,8,11},{0,8,139},{0,8,75},{0,9,247},{16,7,5},{0,8,87},{0,8,23}, |
| 368 | {64,8,0},{19,7,51},{0,8,119},{0,8,55},{0,9,207},{17,7,15},{0,8,103}, |
| 369 | {0,8,39},{0,9,175},{0,8,7},{0,8,135},{0,8,71},{0,9,239},{16,7,9}, |
| 370 | {0,8,95},{0,8,31},{0,9,159},{20,7,99},{0,8,127},{0,8,63},{0,9,223}, |
| 371 | {18,7,27},{0,8,111},{0,8,47},{0,9,191},{0,8,15},{0,8,143},{0,8,79}, |
| 372 | {0,9,255} |
| 373 | }; |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 374 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 375 | static const code distfix[32] = { |
| 376 | {16,5,1},{23,5,257},{19,5,17},{27,5,4097},{17,5,5},{25,5,1025}, |
| 377 | {21,5,65},{29,5,16385},{16,5,3},{24,5,513},{20,5,33},{28,5,8193}, |
| 378 | {18,5,9},{26,5,2049},{22,5,129},{64,5,0},{16,5,2},{23,5,385}, |
| 379 | {19,5,25},{27,5,6145},{17,5,7},{25,5,1537},{21,5,97},{29,5,24577}, |
| 380 | {16,5,4},{24,5,769},{20,5,49},{28,5,12289},{18,5,13},{26,5,3073}, |
| 381 | {22,5,193},{64,5,0} |
| 382 | }; |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 383 | |
| 384 | /*+++++*/ |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 385 | /* inffast.c -- fast decoding |
| 386 | * Copyright (C) 1995-2004 Mark Adler |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 387 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 388 | */ |
| 389 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 390 | /* Allow machine dependent optimization for post-increment or pre-increment. |
| 391 | Based on testing to date, |
| 392 | Pre-increment preferred for: |
| 393 | - PowerPC G3 (Adler) |
| 394 | - MIPS R5000 (Randers-Pehrson) |
| 395 | Post-increment preferred for: |
| 396 | - none |
| 397 | No measurable difference: |
| 398 | - Pentium III (Anderson) |
| 399 | - M68060 (Nikl) |
| 400 | */ |
| 401 | #define OFF 1 |
| 402 | #define PUP(a) *++(a) |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 403 | |
| 404 | /* |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 405 | Decode literal, length, and distance codes and write out the resulting |
| 406 | literal and match bytes until either not enough input or output is |
| 407 | available, an end-of-block is encountered, or a data error is encountered. |
| 408 | When large enough input and output buffers are supplied to inflate(), for |
| 409 | example, a 16K input buffer and a 64K output buffer, more than 95% of the |
| 410 | inflate execution time is spent in this routine. |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 411 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 412 | Entry assumptions: |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 413 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 414 | state->mode == LEN |
| 415 | strm->avail_in >= 6 |
| 416 | strm->avail_out >= 258 |
| 417 | start >= strm->avail_out |
| 418 | state->bits < 8 |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 419 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 420 | On return, state->mode is one of: |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 421 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 422 | LEN -- ran out of enough output space or enough available input |
| 423 | TYPE -- reached end of block code, inflate() to interpret next block |
| 424 | BAD -- error in block data |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 425 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 426 | Notes: |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 427 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 428 | - The maximum input bits used by a length/distance pair is 15 bits for the |
| 429 | length code, 5 bits for the length extra, 15 bits for the distance code, |
| 430 | and 13 bits for the distance extra. This totals 48 bits, or six bytes. |
| 431 | Therefore if strm->avail_in >= 6, then there is enough input to avoid |
| 432 | checking for available input while decoding. |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 433 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 434 | - The maximum bytes that a single length/distance pair can output is 258 |
| 435 | bytes, which is the maximum length that can be coded. inflate_fast() |
| 436 | requires strm->avail_out >= 258 for each loop to avoid checking for |
| 437 | output space. |
| 438 | */ |
| 439 | void inflate_fast(strm, start) |
| 440 | z_streamp strm; |
| 441 | unsigned start; /* inflate()'s starting value for strm->avail_out */ |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 442 | { |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 443 | struct inflate_state FAR *state; |
| 444 | unsigned char FAR *in; /* local strm->next_in */ |
| 445 | unsigned char FAR *last; /* while in < last, enough input available */ |
| 446 | unsigned char FAR *out; /* local strm->next_out */ |
| 447 | unsigned char FAR *beg; /* inflate()'s initial strm->next_out */ |
| 448 | unsigned char FAR *end; /* while out < end, enough space available */ |
| 449 | #ifdef INFLATE_STRICT |
| 450 | unsigned dmax; /* maximum distance from zlib header */ |
Giuseppe CONDORELLI | b4a560a | 2009-07-23 04:54:45 -0400 | [diff] [blame] | 451 | #endif |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 452 | unsigned wsize; /* window size or zero if not using window */ |
| 453 | unsigned whave; /* valid bytes in the window */ |
| 454 | unsigned write; /* window write index */ |
| 455 | unsigned char FAR *window; /* allocated sliding window, if wsize != 0 */ |
| 456 | unsigned long hold; /* local strm->hold */ |
| 457 | unsigned bits; /* local strm->bits */ |
| 458 | code const FAR *lcode; /* local strm->lencode */ |
| 459 | code const FAR *dcode; /* local strm->distcode */ |
| 460 | unsigned lmask; /* mask for first level of length codes */ |
| 461 | unsigned dmask; /* mask for first level of distance codes */ |
| 462 | code this; /* retrieved table entry */ |
| 463 | unsigned op; /* code bits, operation, extra bits, or */ |
| 464 | /* window position, window bytes to copy */ |
| 465 | unsigned len; /* match length, unused bytes */ |
| 466 | unsigned dist; /* match distance */ |
| 467 | unsigned char FAR *from; /* where to copy match from */ |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 468 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 469 | /* copy state to local variables */ |
| 470 | state = (struct inflate_state FAR *)strm->state; |
| 471 | in = strm->next_in - OFF; |
| 472 | last = in + (strm->avail_in - 5); |
| 473 | out = strm->next_out - OFF; |
| 474 | beg = out - (start - strm->avail_out); |
| 475 | end = out + (strm->avail_out - 257); |
| 476 | #ifdef INFLATE_STRICT |
| 477 | dmax = state->dmax; |
| 478 | #endif |
| 479 | wsize = state->wsize; |
| 480 | whave = state->whave; |
| 481 | write = state->write; |
| 482 | window = state->window; |
| 483 | hold = state->hold; |
| 484 | bits = state->bits; |
| 485 | lcode = state->lencode; |
| 486 | dcode = state->distcode; |
| 487 | lmask = (1U << state->lenbits) - 1; |
| 488 | dmask = (1U << state->distbits) - 1; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 489 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 490 | /* decode literals and length/distances until end-of-block or not enough |
| 491 | input data or output space */ |
| 492 | do { |
| 493 | if (bits < 15) { |
| 494 | hold += (unsigned long)(PUP(in)) << bits; |
| 495 | bits += 8; |
| 496 | hold += (unsigned long)(PUP(in)) << bits; |
| 497 | bits += 8; |
| 498 | } |
| 499 | this = lcode[hold & lmask]; |
| 500 | dolen: |
| 501 | op = (unsigned)(this.bits); |
| 502 | hold >>= op; |
| 503 | bits -= op; |
| 504 | op = (unsigned)(this.op); |
| 505 | if (op == 0) { /* literal */ |
| 506 | Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ? |
| 507 | "inflate: literal '%c'\n" : |
| 508 | "inflate: literal 0x%02x\n", this.val)); |
| 509 | PUP(out) = (unsigned char)(this.val); |
| 510 | } |
| 511 | else if (op & 16) { /* length base */ |
| 512 | len = (unsigned)(this.val); |
| 513 | op &= 15; /* number of extra bits */ |
| 514 | if (op) { |
| 515 | if (bits < op) { |
| 516 | hold += (unsigned long)(PUP(in)) << bits; |
| 517 | bits += 8; |
| 518 | } |
| 519 | len += (unsigned)hold & ((1U << op) - 1); |
| 520 | hold >>= op; |
| 521 | bits -= op; |
| 522 | } |
| 523 | Tracevv((stderr, "inflate: length %u\n", len)); |
| 524 | if (bits < 15) { |
| 525 | hold += (unsigned long)(PUP(in)) << bits; |
| 526 | bits += 8; |
| 527 | hold += (unsigned long)(PUP(in)) << bits; |
| 528 | bits += 8; |
| 529 | } |
| 530 | this = dcode[hold & dmask]; |
| 531 | dodist: |
| 532 | op = (unsigned)(this.bits); |
| 533 | hold >>= op; |
| 534 | bits -= op; |
| 535 | op = (unsigned)(this.op); |
| 536 | if (op & 16) { /* distance base */ |
| 537 | dist = (unsigned)(this.val); |
| 538 | op &= 15; /* number of extra bits */ |
| 539 | if (bits < op) { |
| 540 | hold += (unsigned long)(PUP(in)) << bits; |
| 541 | bits += 8; |
| 542 | if (bits < op) { |
| 543 | hold += (unsigned long)(PUP(in)) << bits; |
| 544 | bits += 8; |
| 545 | } |
| 546 | } |
| 547 | dist += (unsigned)hold & ((1U << op) - 1); |
| 548 | #ifdef INFLATE_STRICT |
| 549 | if (dist > dmax) { |
| 550 | strm->msg = (char *)"invalid distance too far back"; |
| 551 | state->mode = BAD; |
| 552 | break; |
| 553 | } |
| 554 | #endif |
| 555 | hold >>= op; |
| 556 | bits -= op; |
| 557 | Tracevv((stderr, "inflate: distance %u\n", dist)); |
| 558 | op = (unsigned)(out - beg); /* max distance in output */ |
| 559 | if (dist > op) { /* see if copy from window */ |
| 560 | op = dist - op; /* distance back in window */ |
| 561 | if (op > whave) { |
| 562 | strm->msg = (char *)"invalid distance too far back"; |
| 563 | state->mode = BAD; |
| 564 | break; |
| 565 | } |
| 566 | from = window - OFF; |
| 567 | if (write == 0) { /* very common case */ |
| 568 | from += wsize - op; |
| 569 | if (op < len) { /* some from window */ |
| 570 | len -= op; |
| 571 | do { |
| 572 | PUP(out) = PUP(from); |
| 573 | } while (--op); |
| 574 | from = out - dist; /* rest from output */ |
| 575 | } |
| 576 | } |
| 577 | else if (write < op) { /* wrap around window */ |
| 578 | from += wsize + write - op; |
| 579 | op -= write; |
| 580 | if (op < len) { /* some from end of window */ |
| 581 | len -= op; |
| 582 | do { |
| 583 | PUP(out) = PUP(from); |
| 584 | } while (--op); |
| 585 | from = window - OFF; |
| 586 | if (write < len) { /* some from start of window */ |
| 587 | op = write; |
| 588 | len -= op; |
| 589 | do { |
| 590 | PUP(out) = PUP(from); |
| 591 | } while (--op); |
| 592 | from = out - dist; /* rest from output */ |
| 593 | } |
| 594 | } |
| 595 | } |
| 596 | else { /* contiguous in window */ |
| 597 | from += write - op; |
| 598 | if (op < len) { /* some from window */ |
| 599 | len -= op; |
| 600 | do { |
| 601 | PUP(out) = PUP(from); |
| 602 | } while (--op); |
| 603 | from = out - dist; /* rest from output */ |
| 604 | } |
| 605 | } |
| 606 | while (len > 2) { |
| 607 | PUP(out) = PUP(from); |
| 608 | PUP(out) = PUP(from); |
| 609 | PUP(out) = PUP(from); |
| 610 | len -= 3; |
| 611 | } |
| 612 | if (len) { |
| 613 | PUP(out) = PUP(from); |
| 614 | if (len > 1) |
| 615 | PUP(out) = PUP(from); |
| 616 | } |
| 617 | } |
| 618 | else { |
| 619 | from = out - dist; /* copy direct from output */ |
| 620 | do { /* minimum length is three */ |
| 621 | PUP(out) = PUP(from); |
| 622 | PUP(out) = PUP(from); |
| 623 | PUP(out) = PUP(from); |
| 624 | len -= 3; |
| 625 | } while (len > 2); |
| 626 | if (len) { |
| 627 | PUP(out) = PUP(from); |
| 628 | if (len > 1) |
| 629 | PUP(out) = PUP(from); |
| 630 | } |
| 631 | } |
| 632 | } |
| 633 | else if ((op & 64) == 0) { /* 2nd level distance code */ |
| 634 | this = dcode[this.val + (hold & ((1U << op) - 1))]; |
| 635 | goto dodist; |
| 636 | } |
| 637 | else { |
| 638 | strm->msg = (char *)"invalid distance code"; |
| 639 | state->mode = BAD; |
| 640 | break; |
| 641 | } |
| 642 | } |
| 643 | else if ((op & 64) == 0) { /* 2nd level length code */ |
| 644 | this = lcode[this.val + (hold & ((1U << op) - 1))]; |
| 645 | goto dolen; |
| 646 | } |
| 647 | else if (op & 32) { /* end-of-block */ |
| 648 | Tracevv((stderr, "inflate: end of block\n")); |
| 649 | state->mode = TYPE; |
| 650 | break; |
| 651 | } |
| 652 | else { |
| 653 | strm->msg = (char *)"invalid literal/length code"; |
| 654 | state->mode = BAD; |
| 655 | break; |
| 656 | } |
| 657 | } while (in < last && out < end); |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 658 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 659 | /* return unused bytes (on entry, bits < 8, so in won't go too far back) */ |
| 660 | len = bits >> 3; |
| 661 | in -= len; |
| 662 | bits -= len << 3; |
| 663 | hold &= (1U << bits) - 1; |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 664 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 665 | /* update state and return */ |
| 666 | strm->next_in = in + OFF; |
| 667 | strm->next_out = out + OFF; |
| 668 | strm->avail_in = (unsigned)(in < last ? 5 + (last - in) : 5 - (in - last)); |
| 669 | strm->avail_out = (unsigned)(out < end ? |
| 670 | 257 + (end - out) : 257 - (out - end)); |
| 671 | state->hold = hold; |
| 672 | state->bits = bits; |
| 673 | return; |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 674 | } |
| 675 | |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 676 | /* |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 677 | inflate_fast() speedups that turned out slower (on a PowerPC G3 750CXe): |
| 678 | - Using bit fields for code structure |
| 679 | - Different op definition to avoid & for extra bits (do & for table bits) |
| 680 | - Three separate decoding do-loops for direct, window, and write == 0 |
| 681 | - Special case for distance > 1 copies to do overlapped load and store copy |
| 682 | - Explicit branch predictions (based on measured branch probabilities) |
| 683 | - Deferring match copy and interspersed it with decoding subsequent codes |
| 684 | - Swapping literal/length else |
| 685 | - Swapping window/direct else |
| 686 | - Larger unrolled copy loops (three is about right) |
| 687 | - Moving len -= 3 statement into middle of loop |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 688 | */ |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 689 | |
| 690 | /*+++++*/ |
| 691 | /* inftrees.c -- generate Huffman trees for efficient decoding |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 692 | * Copyright (C) 1995-2005 Mark Adler |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 693 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 694 | */ |
| 695 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 696 | #define MAXBITS 15 |
| 697 | /* |
| 698 | If you use the zlib library in a product, an acknowledgment is welcome |
| 699 | in the documentation of your product. If for some reason you cannot |
| 700 | include such an acknowledgment, I would appreciate that you keep this |
| 701 | copyright string in the executable of your product. |
| 702 | */ |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 703 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 704 | /* |
| 705 | Build a set of tables to decode the provided canonical Huffman code. |
| 706 | The code lengths are lens[0..codes-1]. The result starts at *table, |
| 707 | whose indices are 0..2^bits-1. work is a writable array of at least |
| 708 | lens shorts, which is used as a work area. type is the type of code |
| 709 | to be generated, CODES, LENS, or DISTS. On return, zero is success, |
| 710 | -1 is an invalid code, and +1 means that ENOUGH isn't enough. table |
| 711 | on return points to the next available entry's address. bits is the |
| 712 | requested root table index bits, and on return it is the actual root |
| 713 | table index bits. It will differ if the request is greater than the |
| 714 | longest code or if it is less than the shortest code. |
| 715 | */ |
| 716 | int inflate_table(type, lens, codes, table, bits, work) |
| 717 | codetype type; |
| 718 | unsigned short FAR *lens; |
| 719 | unsigned codes; |
| 720 | code FAR * FAR *table; |
| 721 | unsigned FAR *bits; |
| 722 | unsigned short FAR *work; |
| 723 | { |
| 724 | unsigned len; /* a code's length in bits */ |
| 725 | unsigned sym; /* index of code symbols */ |
| 726 | unsigned min, max; /* minimum and maximum code lengths */ |
| 727 | unsigned root; /* number of index bits for root table */ |
| 728 | unsigned curr; /* number of index bits for current table */ |
| 729 | unsigned drop; /* code bits to drop for sub-table */ |
| 730 | int left; /* number of prefix codes available */ |
| 731 | unsigned used; /* code entries in table used */ |
| 732 | unsigned huff; /* Huffman code */ |
| 733 | unsigned incr; /* for incrementing code, index */ |
| 734 | unsigned fill; /* index for replicating entries */ |
| 735 | unsigned low; /* low bits for current root entry */ |
| 736 | unsigned mask; /* mask for low root bits */ |
| 737 | code this; /* table entry for duplication */ |
| 738 | code FAR *next; /* next available space in table */ |
| 739 | const unsigned short FAR *base; /* base value table to use */ |
| 740 | const unsigned short FAR *extra; /* extra bits table to use */ |
| 741 | int end; /* use base and extra for symbol > end */ |
| 742 | unsigned short count[MAXBITS+1]; /* number of codes of each length */ |
| 743 | unsigned short offs[MAXBITS+1]; /* offsets in table for each length */ |
| 744 | static const unsigned short lbase[31] = { /* Length codes 257..285 base */ |
| 745 | 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, |
| 746 | 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0}; |
| 747 | static const unsigned short lext[31] = { /* Length codes 257..285 extra */ |
| 748 | 16, 16, 16, 16, 16, 16, 16, 16, 17, 17, 17, 17, 18, 18, 18, 18, |
| 749 | 19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 201, 196}; |
| 750 | static const unsigned short dbase[32] = { /* Distance codes 0..29 base */ |
| 751 | 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, |
| 752 | 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, |
| 753 | 8193, 12289, 16385, 24577, 0, 0}; |
| 754 | static const unsigned short dext[32] = { /* Distance codes 0..29 extra */ |
| 755 | 16, 16, 16, 16, 17, 17, 18, 18, 19, 19, 20, 20, 21, 21, 22, 22, |
| 756 | 23, 23, 24, 24, 25, 25, 26, 26, 27, 27, |
| 757 | 28, 28, 29, 29, 64, 64}; |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 758 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 759 | /* |
| 760 | Process a set of code lengths to create a canonical Huffman code. The |
| 761 | code lengths are lens[0..codes-1]. Each length corresponds to the |
| 762 | symbols 0..codes-1. The Huffman code is generated by first sorting the |
| 763 | symbols by length from short to long, and retaining the symbol order |
| 764 | for codes with equal lengths. Then the code starts with all zero bits |
| 765 | for the first code of the shortest length, and the codes are integer |
| 766 | increments for the same length, and zeros are appended as the length |
| 767 | increases. For the deflate format, these bits are stored backwards |
| 768 | from their more natural integer increment ordering, and so when the |
| 769 | decoding tables are built in the large loop below, the integer codes |
| 770 | are incremented backwards. |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 771 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 772 | This routine assumes, but does not check, that all of the entries in |
| 773 | lens[] are in the range 0..MAXBITS. The caller must assure this. |
| 774 | 1..MAXBITS is interpreted as that code length. zero means that that |
| 775 | symbol does not occur in this code. |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 776 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 777 | The codes are sorted by computing a count of codes for each length, |
| 778 | creating from that a table of starting indices for each length in the |
| 779 | sorted table, and then entering the symbols in order in the sorted |
| 780 | table. The sorted table is work[], with that space being provided by |
| 781 | the caller. |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 782 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 783 | The length counts are used for other purposes as well, i.e. finding |
| 784 | the minimum and maximum length codes, determining if there are any |
| 785 | codes at all, checking for a valid set of lengths, and looking ahead |
| 786 | at length counts to determine sub-table sizes when building the |
| 787 | decoding tables. |
| 788 | */ |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 789 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 790 | /* accumulate lengths for codes (assumes lens[] all in 0..MAXBITS) */ |
| 791 | for (len = 0; len <= MAXBITS; len++) |
| 792 | count[len] = 0; |
| 793 | for (sym = 0; sym < codes; sym++) |
| 794 | count[lens[sym]]++; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 795 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 796 | /* bound code lengths, force root to be within code lengths */ |
| 797 | root = *bits; |
| 798 | for (max = MAXBITS; max >= 1; max--) |
| 799 | if (count[max] != 0) break; |
| 800 | if (root > max) root = max; |
| 801 | if (max == 0) { /* no symbols to code at all */ |
| 802 | this.op = (unsigned char)64; /* invalid code marker */ |
| 803 | this.bits = (unsigned char)1; |
| 804 | this.val = (unsigned short)0; |
| 805 | *(*table)++ = this; /* make a table to force an error */ |
| 806 | *(*table)++ = this; |
| 807 | *bits = 1; |
| 808 | return 0; /* no symbols, but wait for decoding to report error */ |
| 809 | } |
| 810 | for (min = 1; min <= MAXBITS; min++) |
| 811 | if (count[min] != 0) break; |
| 812 | if (root < min) root = min; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 813 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 814 | /* check for an over-subscribed or incomplete set of lengths */ |
| 815 | left = 1; |
| 816 | for (len = 1; len <= MAXBITS; len++) { |
| 817 | left <<= 1; |
| 818 | left -= count[len]; |
| 819 | if (left < 0) return -1; /* over-subscribed */ |
| 820 | } |
| 821 | if (left > 0 && (type == CODES || max != 1)) |
| 822 | return -1; /* incomplete set */ |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 823 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 824 | /* generate offsets into symbol table for each length for sorting */ |
| 825 | offs[1] = 0; |
| 826 | for (len = 1; len < MAXBITS; len++) |
| 827 | offs[len + 1] = offs[len] + count[len]; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 828 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 829 | /* sort symbols by length, by symbol order within each length */ |
| 830 | for (sym = 0; sym < codes; sym++) |
| 831 | if (lens[sym] != 0) work[offs[lens[sym]]++] = (unsigned short)sym; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 832 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 833 | /* |
| 834 | Create and fill in decoding tables. In this loop, the table being |
| 835 | filled is at next and has curr index bits. The code being used is huff |
| 836 | with length len. That code is converted to an index by dropping drop |
| 837 | bits off of the bottom. For codes where len is less than drop + curr, |
| 838 | those top drop + curr - len bits are incremented through all values to |
| 839 | fill the table with replicated entries. |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 840 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 841 | root is the number of index bits for the root table. When len exceeds |
| 842 | root, sub-tables are created pointed to by the root entry with an index |
| 843 | of the low root bits of huff. This is saved in low to check for when a |
| 844 | new sub-table should be started. drop is zero when the root table is |
| 845 | being filled, and drop is root when sub-tables are being filled. |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 846 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 847 | When a new sub-table is needed, it is necessary to look ahead in the |
| 848 | code lengths to determine what size sub-table is needed. The length |
| 849 | counts are used for this, and so count[] is decremented as codes are |
| 850 | entered in the tables. |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 851 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 852 | used keeps track of how many table entries have been allocated from the |
| 853 | provided *table space. It is checked when a LENS table is being made |
| 854 | against the space in *table, ENOUGH, minus the maximum space needed by |
| 855 | the worst case distance code, MAXD. This should never happen, but the |
| 856 | sufficiency of ENOUGH has not been proven exhaustively, hence the check. |
| 857 | This assumes that when type == LENS, bits == 9. |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 858 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 859 | sym increments through all symbols, and the loop terminates when |
| 860 | all codes of length max, i.e. all codes, have been processed. This |
| 861 | routine permits incomplete codes, so another loop after this one fills |
| 862 | in the rest of the decoding tables with invalid code markers. |
| 863 | */ |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 864 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 865 | /* set up for code type */ |
| 866 | switch (type) { |
| 867 | case CODES: |
| 868 | base = extra = work; /* dummy value--not used */ |
| 869 | end = 19; |
| 870 | break; |
| 871 | case LENS: |
| 872 | base = lbase; |
| 873 | base -= 257; |
| 874 | extra = lext; |
| 875 | extra -= 257; |
| 876 | end = 256; |
| 877 | break; |
| 878 | default: /* DISTS */ |
| 879 | base = dbase; |
| 880 | extra = dext; |
| 881 | end = -1; |
| 882 | } |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 883 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 884 | /* initialize state for loop */ |
| 885 | huff = 0; /* starting code */ |
| 886 | sym = 0; /* starting code symbol */ |
| 887 | len = min; /* starting code length */ |
| 888 | next = *table; /* current table to fill in */ |
| 889 | curr = root; /* current table index bits */ |
| 890 | drop = 0; /* current bits to drop from code for index */ |
| 891 | low = (unsigned)(-1); /* trigger new sub-table when len > root */ |
| 892 | used = 1U << root; /* use root table entries */ |
| 893 | mask = used - 1; /* mask for comparing low */ |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 894 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 895 | /* check available table space */ |
| 896 | if (type == LENS && used >= ENOUGH - MAXD) |
| 897 | return 1; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 898 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 899 | /* process all codes and make table entries */ |
| 900 | for (;;) { |
| 901 | /* create table entry */ |
| 902 | this.bits = (unsigned char)(len - drop); |
| 903 | if ((int)(work[sym]) < end) { |
| 904 | this.op = (unsigned char)0; |
| 905 | this.val = work[sym]; |
| 906 | } |
| 907 | else if ((int)(work[sym]) > end) { |
| 908 | this.op = (unsigned char)(extra[work[sym]]); |
| 909 | this.val = base[work[sym]]; |
| 910 | } |
| 911 | else { |
| 912 | this.op = (unsigned char)(32 + 64); /* end of block */ |
| 913 | this.val = 0; |
| 914 | } |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 915 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 916 | /* replicate for those indices with low len bits equal to huff */ |
| 917 | incr = 1U << (len - drop); |
| 918 | fill = 1U << curr; |
| 919 | min = fill; /* save offset to next table */ |
| 920 | do { |
| 921 | fill -= incr; |
| 922 | next[(huff >> drop) + fill] = this; |
| 923 | } while (fill != 0); |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 924 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 925 | /* backwards increment the len-bit code huff */ |
| 926 | incr = 1U << (len - 1); |
| 927 | while (huff & incr) |
| 928 | incr >>= 1; |
| 929 | if (incr != 0) { |
| 930 | huff &= incr - 1; |
| 931 | huff += incr; |
| 932 | } |
| 933 | else |
| 934 | huff = 0; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 935 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 936 | /* go to next symbol, update count, len */ |
| 937 | sym++; |
| 938 | if (--(count[len]) == 0) { |
| 939 | if (len == max) break; |
| 940 | len = lens[work[sym]]; |
| 941 | } |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 942 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 943 | /* create new sub-table if needed */ |
| 944 | if (len > root && (huff & mask) != low) { |
| 945 | /* if first time, transition to sub-tables */ |
| 946 | if (drop == 0) |
| 947 | drop = root; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 948 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 949 | /* increment past last table */ |
| 950 | next += min; /* here min is 1 << curr */ |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 951 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 952 | /* determine length of next table */ |
| 953 | curr = len - drop; |
| 954 | left = (int)(1 << curr); |
| 955 | while (curr + drop < max) { |
| 956 | left -= count[curr + drop]; |
| 957 | if (left <= 0) break; |
| 958 | curr++; |
| 959 | left <<= 1; |
| 960 | } |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 961 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 962 | /* check for enough space */ |
| 963 | used += 1U << curr; |
| 964 | if (type == LENS && used >= ENOUGH - MAXD) |
| 965 | return 1; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 966 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 967 | /* point entry in root table to sub-table */ |
| 968 | low = huff & mask; |
| 969 | (*table)[low].op = (unsigned char)curr; |
| 970 | (*table)[low].bits = (unsigned char)root; |
| 971 | (*table)[low].val = (unsigned short)(next - *table); |
| 972 | } |
| 973 | } |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 974 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 975 | /* |
| 976 | Fill in rest of table for incomplete codes. This loop is similar to the |
| 977 | loop above in incrementing huff for table indices. It is assumed that |
| 978 | len is equal to curr + drop, so there is no loop needed to increment |
| 979 | through high index bits. When the current sub-table is filled, the loop |
| 980 | drops back to the root table to fill in any remaining entries there. |
| 981 | */ |
| 982 | this.op = (unsigned char)64; /* invalid code marker */ |
| 983 | this.bits = (unsigned char)(len - drop); |
| 984 | this.val = (unsigned short)0; |
| 985 | while (huff != 0) { |
| 986 | /* when done with sub-table, drop back to root table */ |
| 987 | if (drop != 0 && (huff & mask) != low) { |
| 988 | drop = 0; |
| 989 | len = root; |
| 990 | next = *table; |
| 991 | this.bits = (unsigned char)len; |
| 992 | } |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 993 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 994 | /* put invalid code marker in table */ |
| 995 | next[huff >> drop] = this; |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 996 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 997 | /* backwards increment the len-bit code huff */ |
| 998 | incr = 1U << (len - 1); |
| 999 | while (huff & incr) |
| 1000 | incr >>= 1; |
| 1001 | if (incr != 0) { |
| 1002 | huff &= incr - 1; |
| 1003 | huff += incr; |
| 1004 | } |
| 1005 | else |
| 1006 | huff = 0; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1007 | } |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1008 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1009 | /* set return parameters */ |
| 1010 | *table += used; |
| 1011 | *bits = root; |
| 1012 | return 0; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1013 | } |
| 1014 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1015 | /*+++++*/ |
| 1016 | /* inflate.c -- zlib decompression |
| 1017 | * Copyright (C) 1995-2005 Mark Adler |
| 1018 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 1019 | */ |
| 1020 | local void fixedtables OF((struct inflate_state FAR *state)); |
| 1021 | local int updatewindow OF((z_streamp strm, unsigned out)); |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1022 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1023 | int ZEXPORT inflateReset(strm) |
| 1024 | z_streamp strm; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1025 | { |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1026 | struct inflate_state FAR *state; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1027 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1028 | if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; |
| 1029 | state = (struct inflate_state FAR *)strm->state; |
| 1030 | strm->total_in = strm->total_out = state->total = 0; |
| 1031 | strm->msg = Z_NULL; |
| 1032 | strm->adler = 1; /* to support ill-conceived Java test suite */ |
| 1033 | state->mode = HEAD; |
| 1034 | state->last = 0; |
| 1035 | state->havedict = 0; |
| 1036 | state->dmax = 32768U; |
| 1037 | state->head = Z_NULL; |
| 1038 | state->wsize = 0; |
| 1039 | state->whave = 0; |
| 1040 | state->write = 0; |
| 1041 | state->hold = 0; |
| 1042 | state->bits = 0; |
| 1043 | state->lencode = state->distcode = state->next = state->codes; |
Giuseppe CONDORELLI | 807b9be | 2009-07-29 06:05:20 -0400 | [diff] [blame] | 1044 | if (strm->outcb != Z_NULL) |
| 1045 | (*strm->outcb)(Z_NULL, 0); |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1046 | Tracev((stderr, "inflate: reset\n")); |
| 1047 | return Z_OK; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1048 | } |
| 1049 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1050 | int ZEXPORT inflateInit2_(strm, windowBits, version, stream_size) |
| 1051 | z_streamp strm; |
| 1052 | int windowBits; |
| 1053 | const char *version; |
| 1054 | int stream_size; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1055 | { |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1056 | struct inflate_state FAR *state; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1057 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1058 | if (version == Z_NULL || version[0] != ZLIB_VERSION[0] || |
| 1059 | stream_size != (int)(sizeof(z_stream))) |
| 1060 | return Z_VERSION_ERROR; |
| 1061 | if (strm == Z_NULL) return Z_STREAM_ERROR; |
| 1062 | strm->msg = Z_NULL; /* in case we return an error */ |
| 1063 | if (strm->zalloc == (alloc_func)0) { |
| 1064 | strm->zalloc = zcalloc; |
| 1065 | strm->opaque = (voidpf)0; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1066 | } |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1067 | if (strm->zfree == (free_func)0) strm->zfree = zcfree; |
| 1068 | state = (struct inflate_state FAR *) |
| 1069 | ZALLOC(strm, 1, sizeof(struct inflate_state)); |
| 1070 | if (state == Z_NULL) return Z_MEM_ERROR; |
| 1071 | Tracev((stderr, "inflate: allocated\n")); |
| 1072 | strm->state = (struct internal_state FAR *)state; |
| 1073 | if (windowBits < 0) { |
| 1074 | state->wrap = 0; |
| 1075 | windowBits = -windowBits; |
Giuseppe CONDORELLI | b4a560a | 2009-07-23 04:54:45 -0400 | [diff] [blame] | 1076 | } |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1077 | else { |
| 1078 | state->wrap = (windowBits >> 4) + 1; |
| 1079 | #ifdef GUNZIP |
| 1080 | if (windowBits < 48) windowBits &= 15; |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 1081 | #endif |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1082 | } |
| 1083 | if (windowBits < 8 || windowBits > 15) { |
| 1084 | ZFREE(strm, state); |
| 1085 | strm->state = Z_NULL; |
| 1086 | return Z_STREAM_ERROR; |
| 1087 | } |
| 1088 | state->wbits = (unsigned)windowBits; |
| 1089 | state->window = Z_NULL; |
| 1090 | return inflateReset(strm); |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1091 | } |
| 1092 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1093 | int ZEXPORT inflateInit_(strm, version, stream_size) |
| 1094 | z_streamp strm; |
| 1095 | const char *version; |
| 1096 | int stream_size; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1097 | { |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1098 | return inflateInit2_(strm, DEF_WBITS, version, stream_size); |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1099 | } |
| 1100 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1101 | local void fixedtables(state) |
| 1102 | struct inflate_state FAR *state; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1103 | { |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1104 | state->lencode = lenfix; |
| 1105 | state->lenbits = 9; |
| 1106 | state->distcode = distfix; |
| 1107 | state->distbits = 5; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1108 | } |
| 1109 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1110 | /* |
| 1111 | Update the window with the last wsize (normally 32K) bytes written before |
| 1112 | returning. If window does not exist yet, create it. This is only called |
| 1113 | when a window is already in use, or when output has been written during this |
| 1114 | inflate call, but the end of the deflate stream has not been reached yet. |
| 1115 | It is also called to create a window for dictionary data when a dictionary |
| 1116 | is loaded. |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1117 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1118 | Providing output buffers larger than 32K to inflate() should provide a speed |
| 1119 | advantage, since only the last 32K of output is copied to the sliding window |
| 1120 | upon return from inflate(), and since all distances after the first 32K of |
| 1121 | output will fall in the output data, making match copies simpler and faster. |
| 1122 | The advantage may be dependent on the size of the processor's data caches. |
| 1123 | */ |
| 1124 | local int updatewindow(strm, out) |
| 1125 | z_streamp strm; |
| 1126 | unsigned out; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1127 | { |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1128 | struct inflate_state FAR *state; |
| 1129 | unsigned copy, dist; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1130 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1131 | state = (struct inflate_state FAR *)strm->state; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1132 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1133 | /* if it hasn't been done already, allocate space for the window */ |
| 1134 | if (state->window == Z_NULL) { |
| 1135 | state->window = (unsigned char FAR *) |
| 1136 | ZALLOC(strm, 1U << state->wbits, |
| 1137 | sizeof(unsigned char)); |
| 1138 | if (state->window == Z_NULL) return 1; |
| 1139 | } |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1140 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1141 | /* if window not in use yet, initialize */ |
| 1142 | if (state->wsize == 0) { |
| 1143 | state->wsize = 1U << state->wbits; |
| 1144 | state->write = 0; |
| 1145 | state->whave = 0; |
| 1146 | } |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1147 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1148 | /* copy state->wsize or less output bytes into the circular window */ |
| 1149 | copy = out - strm->avail_out; |
| 1150 | if (copy >= state->wsize) { |
| 1151 | zmemcpy(state->window, strm->next_out - state->wsize, state->wsize); |
| 1152 | state->write = 0; |
| 1153 | state->whave = state->wsize; |
| 1154 | } |
| 1155 | else { |
| 1156 | dist = state->wsize - state->write; |
| 1157 | if (dist > copy) dist = copy; |
| 1158 | zmemcpy(state->window + state->write, strm->next_out - copy, dist); |
| 1159 | copy -= dist; |
| 1160 | if (copy) { |
| 1161 | zmemcpy(state->window, strm->next_out - copy, copy); |
| 1162 | state->write = copy; |
| 1163 | state->whave = state->wsize; |
| 1164 | } |
| 1165 | else { |
| 1166 | state->write += dist; |
| 1167 | if (state->write == state->wsize) state->write = 0; |
| 1168 | if (state->whave < state->wsize) state->whave += dist; |
| 1169 | } |
| 1170 | } |
| 1171 | return 0; |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 1172 | } |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1173 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1174 | /* Macros for inflate(): */ |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1175 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1176 | /* check function to use adler32() for zlib or crc32() for gzip */ |
| 1177 | #define UPDATE(check, buf, len) \ |
| 1178 | (state->flags ? crc32(check, buf, len) : adler32(check, buf, len)) |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1179 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1180 | /* check macros for header crc */ |
| 1181 | #define CRC2(check, word) \ |
| 1182 | do { \ |
| 1183 | hbuf[0] = (unsigned char)(word); \ |
| 1184 | hbuf[1] = (unsigned char)((word) >> 8); \ |
| 1185 | check = crc32(check, hbuf, 2); \ |
| 1186 | } while (0) |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1187 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1188 | #define CRC4(check, word) \ |
| 1189 | do { \ |
| 1190 | hbuf[0] = (unsigned char)(word); \ |
| 1191 | hbuf[1] = (unsigned char)((word) >> 8); \ |
| 1192 | hbuf[2] = (unsigned char)((word) >> 16); \ |
| 1193 | hbuf[3] = (unsigned char)((word) >> 24); \ |
| 1194 | check = crc32(check, hbuf, 4); \ |
| 1195 | } while (0) |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1196 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1197 | /* Load registers with state in inflate() for speed */ |
| 1198 | #define LOAD() \ |
| 1199 | do { \ |
| 1200 | put = strm->next_out; \ |
| 1201 | left = strm->avail_out; \ |
| 1202 | next = strm->next_in; \ |
| 1203 | have = strm->avail_in; \ |
| 1204 | hold = state->hold; \ |
| 1205 | bits = state->bits; \ |
| 1206 | } while (0) |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1207 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1208 | /* Restore state from registers in inflate() */ |
| 1209 | #define RESTORE() \ |
| 1210 | do { \ |
| 1211 | strm->next_out = put; \ |
| 1212 | strm->avail_out = left; \ |
| 1213 | strm->next_in = next; \ |
| 1214 | strm->avail_in = have; \ |
| 1215 | state->hold = hold; \ |
| 1216 | state->bits = bits; \ |
| 1217 | } while (0) |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 1218 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1219 | /* Clear the input bit accumulator */ |
| 1220 | #define INITBITS() \ |
| 1221 | do { \ |
| 1222 | hold = 0; \ |
| 1223 | bits = 0; \ |
| 1224 | } while (0) |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1225 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1226 | /* Get a byte of input into the bit accumulator, or return from inflate() |
| 1227 | if there is no input available. */ |
| 1228 | #define PULLBYTE() \ |
| 1229 | do { \ |
| 1230 | if (have == 0) goto inf_leave; \ |
| 1231 | have--; \ |
| 1232 | hold += (unsigned long)(*next++) << bits; \ |
| 1233 | bits += 8; \ |
| 1234 | } while (0) |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1235 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1236 | /* Assure that there are at least n bits in the bit accumulator. If there is |
| 1237 | not enough available input to do that, then return from inflate(). */ |
| 1238 | #define NEEDBITS(n) \ |
| 1239 | do { \ |
| 1240 | while (bits < (unsigned)(n)) \ |
| 1241 | PULLBYTE(); \ |
| 1242 | } while (0) |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1243 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1244 | /* Return the low n bits of the bit accumulator (n < 16) */ |
| 1245 | #define BITS(n) \ |
| 1246 | ((unsigned)hold & ((1U << (n)) - 1)) |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1247 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1248 | /* Remove n bits from the bit accumulator */ |
| 1249 | #define DROPBITS(n) \ |
| 1250 | do { \ |
| 1251 | hold >>= (n); \ |
| 1252 | bits -= (unsigned)(n); \ |
| 1253 | } while (0) |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1254 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1255 | /* Remove zero to seven bits as needed to go to a byte boundary */ |
| 1256 | #define BYTEBITS() \ |
| 1257 | do { \ |
| 1258 | hold >>= bits & 7; \ |
| 1259 | bits -= bits & 7; \ |
| 1260 | } while (0) |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 1261 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1262 | /* Reverse the bytes in a 32-bit value */ |
| 1263 | #define REVERSE(q) \ |
| 1264 | ((((q) >> 24) & 0xff) + (((q) >> 8) & 0xff00) + \ |
| 1265 | (((q) & 0xff00) << 8) + (((q) & 0xff) << 24)) |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1266 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1267 | /* |
| 1268 | inflate() uses a state machine to process as much input data and generate as |
| 1269 | much output data as possible before returning. The state machine is |
| 1270 | structured roughly as follows: |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1271 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1272 | for (;;) switch (state) { |
| 1273 | ... |
| 1274 | case STATEn: |
| 1275 | if (not enough input data or output space to make progress) |
| 1276 | return; |
| 1277 | ... make progress ... |
| 1278 | state = STATEm; |
| 1279 | break; |
| 1280 | ... |
| 1281 | } |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1282 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1283 | so when inflate() is called again, the same case is attempted again, and |
| 1284 | if the appropriate resources are provided, the machine proceeds to the |
| 1285 | next state. The NEEDBITS() macro is usually the way the state evaluates |
| 1286 | whether it can proceed or should return. NEEDBITS() does the return if |
| 1287 | the requested bits are not available. The typical use of the BITS macros |
| 1288 | is: |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1289 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1290 | NEEDBITS(n); |
| 1291 | ... do something with BITS(n) ... |
| 1292 | DROPBITS(n); |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1293 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1294 | where NEEDBITS(n) either returns from inflate() if there isn't enough |
| 1295 | input left to load n bits into the accumulator, or it continues. BITS(n) |
| 1296 | gives the low n bits in the accumulator. When done, DROPBITS(n) drops |
| 1297 | the low n bits off the accumulator. INITBITS() clears the accumulator |
| 1298 | and sets the number of available bits to zero. BYTEBITS() discards just |
| 1299 | enough bits to put the accumulator on a byte boundary. After BYTEBITS() |
| 1300 | and a NEEDBITS(8), then BITS(8) would return the next byte in the stream. |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1301 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1302 | NEEDBITS(n) uses PULLBYTE() to get an available byte of input, or to return |
| 1303 | if there is no input available. The decoding of variable length codes uses |
| 1304 | PULLBYTE() directly in order to pull just enough bytes to decode the next |
| 1305 | code, and no more. |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1306 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1307 | Some states loop until they get enough input, making sure that enough |
| 1308 | state information is maintained to continue the loop where it left off |
| 1309 | if NEEDBITS() returns in the loop. For example, want, need, and keep |
| 1310 | would all have to actually be part of the saved state in case NEEDBITS() |
| 1311 | returns: |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1312 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1313 | case STATEw: |
| 1314 | while (want < need) { |
| 1315 | NEEDBITS(n); |
| 1316 | keep[want++] = BITS(n); |
| 1317 | DROPBITS(n); |
| 1318 | } |
| 1319 | state = STATEx; |
| 1320 | case STATEx: |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1321 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1322 | As shown above, if the next state is also the next case, then the break |
| 1323 | is omitted. |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1324 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1325 | A state may also return if there is not enough output space available to |
| 1326 | complete that state. Those states are copying stored data, writing a |
| 1327 | literal byte, and copying a matching string. |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1328 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1329 | When returning, a "goto inf_leave" is used to update the total counters, |
| 1330 | update the check value, and determine whether any progress has been made |
| 1331 | during that inflate() call in order to return the proper return code. |
| 1332 | Progress is defined as a change in either strm->avail_in or strm->avail_out. |
| 1333 | When there is a window, goto inf_leave will update the window with the last |
| 1334 | output written. If a goto inf_leave occurs in the middle of decompression |
| 1335 | and there is no window currently, goto inf_leave will create one and copy |
| 1336 | output to the window for the next call of inflate(). |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1337 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1338 | In this implementation, the flush parameter of inflate() only affects the |
| 1339 | return code (per zlib.h). inflate() always writes as much as possible to |
| 1340 | strm->next_out, given the space available and the provided input--the effect |
| 1341 | documented in zlib.h of Z_SYNC_FLUSH. Furthermore, inflate() always defers |
| 1342 | the allocation of and copying into a sliding window until necessary, which |
| 1343 | provides the effect documented in zlib.h for Z_FINISH when the entire input |
| 1344 | stream available. So the only thing the flush parameter actually does is: |
| 1345 | when flush is set to Z_FINISH, inflate() cannot return Z_OK. Instead it |
| 1346 | will return Z_BUF_ERROR if it has not reached the end of the stream. |
| 1347 | */ |
| 1348 | int ZEXPORT inflate(strm, flush) |
| 1349 | z_streamp strm; |
| 1350 | int flush; |
| 1351 | { |
| 1352 | struct inflate_state FAR *state; |
| 1353 | unsigned char FAR *next; /* next input */ |
| 1354 | unsigned char FAR *put; /* next output */ |
| 1355 | unsigned have, left; /* available input and output */ |
| 1356 | unsigned long hold; /* bit buffer */ |
| 1357 | unsigned bits; /* bits in bit buffer */ |
| 1358 | unsigned in, out; /* save starting available input and output */ |
| 1359 | unsigned copy; /* number of stored or match bytes to copy */ |
| 1360 | unsigned char FAR *from; /* where to copy match bytes from */ |
| 1361 | code this; /* current decoding table entry */ |
| 1362 | code last; /* parent table entry */ |
| 1363 | unsigned len; /* length to copy for repeats, bits to drop */ |
| 1364 | int ret; /* return code */ |
| 1365 | #ifdef GUNZIP |
| 1366 | unsigned char hbuf[4]; /* buffer for gzip header crc calculation */ |
| 1367 | #endif |
| 1368 | static const unsigned short order[19] = /* permutation of code lengths */ |
| 1369 | {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1370 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1371 | if (strm == Z_NULL || strm->state == Z_NULL || |
| 1372 | (strm->next_in == Z_NULL && strm->avail_in != 0)) |
| 1373 | return Z_STREAM_ERROR; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1374 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1375 | state = (struct inflate_state FAR *)strm->state; |
| 1376 | if (state->mode == TYPE) state->mode = TYPEDO; /* skip check */ |
| 1377 | LOAD(); |
| 1378 | in = have; |
| 1379 | out = left; |
| 1380 | ret = Z_OK; |
| 1381 | for (;;) |
| 1382 | switch (state->mode) { |
| 1383 | case HEAD: |
| 1384 | if (state->wrap == 0) { |
| 1385 | state->mode = TYPEDO; |
| 1386 | break; |
| 1387 | } |
| 1388 | NEEDBITS(16); |
| 1389 | #ifdef GUNZIP |
| 1390 | if ((state->wrap & 2) && hold == 0x8b1f) { /* gzip header */ |
| 1391 | state->check = crc32(0L, Z_NULL, 0); |
| 1392 | CRC2(state->check, hold); |
| 1393 | INITBITS(); |
| 1394 | state->mode = FLAGS; |
| 1395 | break; |
| 1396 | } |
| 1397 | state->flags = 0; /* expect zlib header */ |
| 1398 | if (state->head != Z_NULL) |
| 1399 | state->head->done = -1; |
| 1400 | if (!(state->wrap & 1) || /* check if zlib header allowed */ |
| 1401 | #else |
| 1402 | if ( |
| 1403 | #endif |
| 1404 | ((BITS(8) << 8) + (hold >> 8)) % 31) { |
| 1405 | strm->msg = (char *)"incorrect header check"; |
| 1406 | state->mode = BAD; |
| 1407 | break; |
| 1408 | } |
| 1409 | if (BITS(4) != Z_DEFLATED) { |
| 1410 | strm->msg = (char *)"unknown compression method"; |
| 1411 | state->mode = BAD; |
| 1412 | break; |
| 1413 | } |
| 1414 | DROPBITS(4); |
| 1415 | len = BITS(4) + 8; |
| 1416 | if (len > state->wbits) { |
| 1417 | strm->msg = (char *)"invalid window size"; |
| 1418 | state->mode = BAD; |
| 1419 | break; |
| 1420 | } |
| 1421 | state->dmax = 1U << len; |
| 1422 | Tracev((stderr, "inflate: zlib header ok\n")); |
| 1423 | strm->adler = state->check = adler32(0L, Z_NULL, 0); |
| 1424 | state->mode = hold & 0x200 ? DICTID : TYPE; |
| 1425 | INITBITS(); |
| 1426 | break; |
| 1427 | #ifdef GUNZIP |
| 1428 | case FLAGS: |
| 1429 | NEEDBITS(16); |
| 1430 | state->flags = (int)(hold); |
| 1431 | if ((state->flags & 0xff) != Z_DEFLATED) { |
| 1432 | strm->msg = (char *)"unknown compression method"; |
| 1433 | state->mode = BAD; |
| 1434 | break; |
| 1435 | } |
| 1436 | if (state->flags & 0xe000) { |
| 1437 | strm->msg = (char *)"unknown header flags set"; |
| 1438 | state->mode = BAD; |
| 1439 | break; |
| 1440 | } |
| 1441 | if (state->head != Z_NULL) |
| 1442 | state->head->text = (int)((hold >> 8) & 1); |
| 1443 | if (state->flags & 0x0200) CRC2(state->check, hold); |
| 1444 | INITBITS(); |
| 1445 | state->mode = TIME; |
| 1446 | case TIME: |
| 1447 | NEEDBITS(32); |
| 1448 | if (state->head != Z_NULL) |
| 1449 | state->head->time = hold; |
| 1450 | if (state->flags & 0x0200) CRC4(state->check, hold); |
| 1451 | INITBITS(); |
| 1452 | state->mode = OS; |
| 1453 | case OS: |
| 1454 | NEEDBITS(16); |
| 1455 | if (state->head != Z_NULL) { |
| 1456 | state->head->xflags = (int)(hold & 0xff); |
| 1457 | state->head->os = (int)(hold >> 8); |
| 1458 | } |
| 1459 | if (state->flags & 0x0200) CRC2(state->check, hold); |
| 1460 | INITBITS(); |
| 1461 | state->mode = EXLEN; |
| 1462 | case EXLEN: |
| 1463 | if (state->flags & 0x0400) { |
| 1464 | NEEDBITS(16); |
| 1465 | state->length = (unsigned)(hold); |
| 1466 | if (state->head != Z_NULL) |
| 1467 | state->head->extra_len = (unsigned)hold; |
| 1468 | if (state->flags & 0x0200) CRC2(state->check, hold); |
| 1469 | INITBITS(); |
| 1470 | } |
| 1471 | else if (state->head != Z_NULL) |
| 1472 | state->head->extra = Z_NULL; |
| 1473 | state->mode = EXTRA; |
| 1474 | case EXTRA: |
| 1475 | if (state->flags & 0x0400) { |
| 1476 | copy = state->length; |
| 1477 | if (copy > have) copy = have; |
| 1478 | if (copy) { |
| 1479 | if (state->head != Z_NULL && |
| 1480 | state->head->extra != Z_NULL) { |
| 1481 | len = state->head->extra_len - state->length; |
| 1482 | zmemcpy(state->head->extra + len, next, |
| 1483 | len + copy > state->head->extra_max ? |
| 1484 | state->head->extra_max - len : copy); |
| 1485 | } |
| 1486 | if (state->flags & 0x0200) |
| 1487 | state->check = crc32(state->check, next, copy); |
| 1488 | have -= copy; |
| 1489 | next += copy; |
| 1490 | state->length -= copy; |
| 1491 | } |
| 1492 | if (state->length) goto inf_leave; |
| 1493 | } |
| 1494 | state->length = 0; |
| 1495 | state->mode = NAME; |
| 1496 | case NAME: |
| 1497 | if (state->flags & 0x0800) { |
| 1498 | if (have == 0) goto inf_leave; |
| 1499 | copy = 0; |
| 1500 | do { |
| 1501 | len = (unsigned)(next[copy++]); |
| 1502 | if (state->head != Z_NULL && |
| 1503 | state->head->name != Z_NULL && |
| 1504 | state->length < state->head->name_max) |
| 1505 | state->head->name[state->length++] = len; |
| 1506 | } while (len && copy < have); |
| 1507 | if (state->flags & 0x0200) |
| 1508 | state->check = crc32(state->check, next, copy); |
| 1509 | have -= copy; |
| 1510 | next += copy; |
| 1511 | if (len) goto inf_leave; |
| 1512 | } |
| 1513 | else if (state->head != Z_NULL) |
| 1514 | state->head->name = Z_NULL; |
| 1515 | state->length = 0; |
| 1516 | state->mode = COMMENT; |
| 1517 | case COMMENT: |
| 1518 | if (state->flags & 0x1000) { |
| 1519 | if (have == 0) goto inf_leave; |
| 1520 | copy = 0; |
| 1521 | do { |
| 1522 | len = (unsigned)(next[copy++]); |
| 1523 | if (state->head != Z_NULL && |
| 1524 | state->head->comment != Z_NULL && |
| 1525 | state->length < state->head->comm_max) |
| 1526 | state->head->comment[state->length++] = len; |
| 1527 | } while (len && copy < have); |
| 1528 | if (state->flags & 0x0200) |
| 1529 | state->check = crc32(state->check, next, copy); |
| 1530 | have -= copy; |
| 1531 | next += copy; |
| 1532 | if (len) goto inf_leave; |
| 1533 | } |
| 1534 | else if (state->head != Z_NULL) |
| 1535 | state->head->comment = Z_NULL; |
| 1536 | state->mode = HCRC; |
| 1537 | case HCRC: |
| 1538 | if (state->flags & 0x0200) { |
| 1539 | NEEDBITS(16); |
| 1540 | if (hold != (state->check & 0xffff)) { |
| 1541 | strm->msg = (char *)"header crc mismatch"; |
| 1542 | state->mode = BAD; |
| 1543 | break; |
| 1544 | } |
| 1545 | INITBITS(); |
| 1546 | } |
| 1547 | if (state->head != Z_NULL) { |
| 1548 | state->head->hcrc = (int)((state->flags >> 9) & 1); |
| 1549 | state->head->done = 1; |
| 1550 | } |
| 1551 | strm->adler = state->check = crc32(0L, Z_NULL, 0); |
| 1552 | state->mode = TYPE; |
| 1553 | break; |
| 1554 | #endif |
| 1555 | case DICTID: |
| 1556 | NEEDBITS(32); |
| 1557 | strm->adler = state->check = REVERSE(hold); |
| 1558 | INITBITS(); |
| 1559 | state->mode = DICT; |
| 1560 | case DICT: |
| 1561 | if (state->havedict == 0) { |
| 1562 | RESTORE(); |
| 1563 | return Z_NEED_DICT; |
| 1564 | } |
| 1565 | strm->adler = state->check = adler32(0L, Z_NULL, 0); |
| 1566 | state->mode = TYPE; |
| 1567 | case TYPE: |
| 1568 | if (flush == Z_BLOCK) goto inf_leave; |
| 1569 | case TYPEDO: |
| 1570 | if (state->last) { |
| 1571 | BYTEBITS(); |
| 1572 | state->mode = CHECK; |
| 1573 | break; |
| 1574 | } |
| 1575 | NEEDBITS(3); |
| 1576 | state->last = BITS(1); |
| 1577 | DROPBITS(1); |
| 1578 | switch (BITS(2)) { |
| 1579 | case 0: /* stored block */ |
| 1580 | Tracev((stderr, "inflate: stored block%s\n", |
| 1581 | state->last ? " (last)" : "")); |
| 1582 | state->mode = STORED; |
| 1583 | break; |
| 1584 | case 1: /* fixed block */ |
| 1585 | fixedtables(state); |
| 1586 | Tracev((stderr, "inflate: fixed codes block%s\n", |
| 1587 | state->last ? " (last)" : "")); |
| 1588 | state->mode = LEN; /* decode codes */ |
| 1589 | break; |
| 1590 | case 2: /* dynamic block */ |
| 1591 | Tracev((stderr, "inflate: dynamic codes block%s\n", |
| 1592 | state->last ? " (last)" : "")); |
| 1593 | state->mode = TABLE; |
| 1594 | break; |
| 1595 | case 3: |
| 1596 | strm->msg = (char *)"invalid block type"; |
| 1597 | state->mode = BAD; |
| 1598 | } |
| 1599 | DROPBITS(2); |
| 1600 | break; |
| 1601 | case STORED: |
| 1602 | BYTEBITS(); /* go to byte boundary */ |
| 1603 | NEEDBITS(32); |
| 1604 | if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) { |
| 1605 | strm->msg = (char *)"invalid stored block lengths"; |
| 1606 | state->mode = BAD; |
| 1607 | break; |
| 1608 | } |
| 1609 | state->length = (unsigned)hold & 0xffff; |
| 1610 | Tracev((stderr, "inflate: stored length %u\n", |
| 1611 | state->length)); |
| 1612 | INITBITS(); |
| 1613 | state->mode = COPY; |
| 1614 | case COPY: |
| 1615 | copy = state->length; |
| 1616 | if (copy) { |
| 1617 | if (copy > have) copy = have; |
| 1618 | if (copy > left) copy = left; |
| 1619 | if (copy == 0) goto inf_leave; |
| 1620 | zmemcpy(put, next, copy); |
| 1621 | have -= copy; |
| 1622 | next += copy; |
| 1623 | left -= copy; |
| 1624 | put += copy; |
| 1625 | state->length -= copy; |
| 1626 | break; |
| 1627 | } |
| 1628 | Tracev((stderr, "inflate: stored end\n")); |
| 1629 | state->mode = TYPE; |
| 1630 | break; |
| 1631 | case TABLE: |
| 1632 | NEEDBITS(14); |
| 1633 | state->nlen = BITS(5) + 257; |
| 1634 | DROPBITS(5); |
| 1635 | state->ndist = BITS(5) + 1; |
| 1636 | DROPBITS(5); |
| 1637 | state->ncode = BITS(4) + 4; |
| 1638 | DROPBITS(4); |
| 1639 | #ifndef PKZIP_BUG_WORKAROUND |
| 1640 | if (state->nlen > 286 || state->ndist > 30) { |
| 1641 | strm->msg = (char *)"too many length or distance symbols"; |
| 1642 | state->mode = BAD; |
| 1643 | break; |
| 1644 | } |
| 1645 | #endif |
| 1646 | Tracev((stderr, "inflate: table sizes ok\n")); |
| 1647 | state->have = 0; |
| 1648 | state->mode = LENLENS; |
| 1649 | case LENLENS: |
| 1650 | while (state->have < state->ncode) { |
| 1651 | NEEDBITS(3); |
| 1652 | state->lens[order[state->have++]] = (unsigned short)BITS(3); |
| 1653 | DROPBITS(3); |
| 1654 | } |
| 1655 | while (state->have < 19) |
| 1656 | state->lens[order[state->have++]] = 0; |
| 1657 | state->next = state->codes; |
| 1658 | state->lencode = (code const FAR *)(state->next); |
| 1659 | state->lenbits = 7; |
| 1660 | ret = inflate_table(CODES, state->lens, 19, &(state->next), |
| 1661 | &(state->lenbits), state->work); |
| 1662 | if (ret) { |
| 1663 | strm->msg = (char *)"invalid code lengths set"; |
| 1664 | state->mode = BAD; |
| 1665 | break; |
| 1666 | } |
| 1667 | Tracev((stderr, "inflate: code lengths ok\n")); |
| 1668 | state->have = 0; |
| 1669 | state->mode = CODELENS; |
| 1670 | case CODELENS: |
| 1671 | while (state->have < state->nlen + state->ndist) { |
| 1672 | for (;;) { |
| 1673 | this = state->lencode[BITS(state->lenbits)]; |
| 1674 | if ((unsigned)(this.bits) <= bits) break; |
| 1675 | PULLBYTE(); |
| 1676 | } |
| 1677 | if (this.val < 16) { |
| 1678 | NEEDBITS(this.bits); |
| 1679 | DROPBITS(this.bits); |
| 1680 | state->lens[state->have++] = this.val; |
| 1681 | } |
| 1682 | else { |
| 1683 | if (this.val == 16) { |
| 1684 | NEEDBITS(this.bits + 2); |
| 1685 | DROPBITS(this.bits); |
| 1686 | if (state->have == 0) { |
| 1687 | strm->msg = (char *)"invalid bit length repeat"; |
| 1688 | state->mode = BAD; |
| 1689 | break; |
| 1690 | } |
| 1691 | len = state->lens[state->have - 1]; |
| 1692 | copy = 3 + BITS(2); |
| 1693 | DROPBITS(2); |
| 1694 | } |
| 1695 | else if (this.val == 17) { |
| 1696 | NEEDBITS(this.bits + 3); |
| 1697 | DROPBITS(this.bits); |
| 1698 | len = 0; |
| 1699 | copy = 3 + BITS(3); |
| 1700 | DROPBITS(3); |
| 1701 | } |
| 1702 | else { |
| 1703 | NEEDBITS(this.bits + 7); |
| 1704 | DROPBITS(this.bits); |
| 1705 | len = 0; |
| 1706 | copy = 11 + BITS(7); |
| 1707 | DROPBITS(7); |
| 1708 | } |
| 1709 | if (state->have + copy > state->nlen + state->ndist) { |
| 1710 | strm->msg = (char *)"invalid bit length repeat"; |
| 1711 | state->mode = BAD; |
| 1712 | break; |
| 1713 | } |
| 1714 | while (copy--) |
| 1715 | state->lens[state->have++] = (unsigned short)len; |
| 1716 | } |
| 1717 | } |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1718 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1719 | /* handle error breaks in while */ |
| 1720 | if (state->mode == BAD) break; |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 1721 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1722 | /* build code tables */ |
| 1723 | state->next = state->codes; |
| 1724 | state->lencode = (code const FAR *)(state->next); |
| 1725 | state->lenbits = 9; |
| 1726 | ret = inflate_table(LENS, state->lens, state->nlen, &(state->next), |
| 1727 | &(state->lenbits), state->work); |
| 1728 | if (ret) { |
| 1729 | strm->msg = (char *)"invalid literal/lengths set"; |
| 1730 | state->mode = BAD; |
| 1731 | break; |
| 1732 | } |
| 1733 | state->distcode = (code const FAR *)(state->next); |
| 1734 | state->distbits = 6; |
| 1735 | ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist, |
| 1736 | &(state->next), &(state->distbits), state->work); |
| 1737 | if (ret) { |
| 1738 | strm->msg = (char *)"invalid distances set"; |
| 1739 | state->mode = BAD; |
| 1740 | break; |
| 1741 | } |
| 1742 | Tracev((stderr, "inflate: codes ok\n")); |
| 1743 | state->mode = LEN; |
| 1744 | case LEN: |
| 1745 | if (strm->outcb != Z_NULL) /* for watchdog (U-Boot) */ |
| 1746 | (*strm->outcb)(Z_NULL, 0); |
| 1747 | if (have >= 6 && left >= 258) { |
| 1748 | RESTORE(); |
| 1749 | inflate_fast(strm, out); |
| 1750 | LOAD(); |
| 1751 | break; |
| 1752 | } |
| 1753 | for (;;) { |
| 1754 | this = state->lencode[BITS(state->lenbits)]; |
| 1755 | if ((unsigned)(this.bits) <= bits) break; |
| 1756 | PULLBYTE(); |
| 1757 | } |
| 1758 | if (this.op && (this.op & 0xf0) == 0) { |
| 1759 | last = this; |
| 1760 | for (;;) { |
| 1761 | this = state->lencode[last.val + |
| 1762 | (BITS(last.bits + last.op) >> last.bits)]; |
| 1763 | if ((unsigned)(last.bits + this.bits) <= bits) break; |
| 1764 | PULLBYTE(); |
| 1765 | } |
| 1766 | DROPBITS(last.bits); |
| 1767 | } |
| 1768 | DROPBITS(this.bits); |
| 1769 | state->length = (unsigned)this.val; |
| 1770 | if ((int)(this.op) == 0) { |
| 1771 | Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ? |
| 1772 | "inflate: literal '%c'\n" : |
| 1773 | "inflate: literal 0x%02x\n", this.val)); |
| 1774 | state->mode = LIT; |
| 1775 | break; |
| 1776 | } |
| 1777 | if (this.op & 32) { |
| 1778 | Tracevv((stderr, "inflate: end of block\n")); |
| 1779 | state->mode = TYPE; |
| 1780 | break; |
| 1781 | } |
| 1782 | if (this.op & 64) { |
| 1783 | strm->msg = (char *)"invalid literal/length code"; |
| 1784 | state->mode = BAD; |
| 1785 | break; |
| 1786 | } |
| 1787 | state->extra = (unsigned)(this.op) & 15; |
| 1788 | state->mode = LENEXT; |
| 1789 | case LENEXT: |
| 1790 | if (state->extra) { |
| 1791 | NEEDBITS(state->extra); |
| 1792 | state->length += BITS(state->extra); |
| 1793 | DROPBITS(state->extra); |
| 1794 | } |
| 1795 | Tracevv((stderr, "inflate: length %u\n", state->length)); |
| 1796 | state->mode = DIST; |
| 1797 | case DIST: |
| 1798 | for (;;) { |
| 1799 | this = state->distcode[BITS(state->distbits)]; |
| 1800 | if ((unsigned)(this.bits) <= bits) break; |
| 1801 | PULLBYTE(); |
| 1802 | } |
| 1803 | if ((this.op & 0xf0) == 0) { |
| 1804 | last = this; |
| 1805 | for (;;) { |
| 1806 | this = state->distcode[last.val + |
| 1807 | (BITS(last.bits + last.op) >> last.bits)]; |
| 1808 | if ((unsigned)(last.bits + this.bits) <= bits) break; |
| 1809 | PULLBYTE(); |
| 1810 | } |
| 1811 | DROPBITS(last.bits); |
| 1812 | } |
| 1813 | DROPBITS(this.bits); |
| 1814 | if (this.op & 64) { |
| 1815 | strm->msg = (char *)"invalid distance code"; |
| 1816 | state->mode = BAD; |
| 1817 | break; |
| 1818 | } |
| 1819 | state->offset = (unsigned)this.val; |
| 1820 | state->extra = (unsigned)(this.op) & 15; |
| 1821 | state->mode = DISTEXT; |
| 1822 | case DISTEXT: |
| 1823 | if (state->extra) { |
| 1824 | NEEDBITS(state->extra); |
| 1825 | state->offset += BITS(state->extra); |
| 1826 | DROPBITS(state->extra); |
| 1827 | } |
| 1828 | #ifdef INFLATE_STRICT |
| 1829 | if (state->offset > state->dmax) { |
| 1830 | strm->msg = (char *)"invalid distance too far back"; |
| 1831 | state->mode = BAD; |
| 1832 | break; |
| 1833 | } |
| 1834 | #endif |
| 1835 | if (state->offset > state->whave + out - left) { |
| 1836 | strm->msg = (char *)"invalid distance too far back"; |
| 1837 | state->mode = BAD; |
| 1838 | break; |
| 1839 | } |
| 1840 | Tracevv((stderr, "inflate: distance %u\n", state->offset)); |
| 1841 | state->mode = MATCH; |
| 1842 | case MATCH: |
| 1843 | if (left == 0) goto inf_leave; |
| 1844 | copy = out - left; |
| 1845 | if (state->offset > copy) { /* copy from window */ |
| 1846 | copy = state->offset - copy; |
| 1847 | if (copy > state->write) { |
| 1848 | copy -= state->write; |
| 1849 | from = state->window + (state->wsize - copy); |
| 1850 | } |
| 1851 | else |
| 1852 | from = state->window + (state->write - copy); |
| 1853 | if (copy > state->length) copy = state->length; |
| 1854 | } |
| 1855 | else { /* copy from output */ |
| 1856 | from = put - state->offset; |
| 1857 | copy = state->length; |
| 1858 | } |
| 1859 | if (copy > left) copy = left; |
| 1860 | left -= copy; |
| 1861 | state->length -= copy; |
| 1862 | do { |
| 1863 | *put++ = *from++; |
| 1864 | } while (--copy); |
| 1865 | if (state->length == 0) state->mode = LEN; |
| 1866 | break; |
| 1867 | case LIT: |
| 1868 | if (left == 0) goto inf_leave; |
| 1869 | *put++ = (unsigned char)(state->length); |
| 1870 | left--; |
| 1871 | state->mode = LEN; |
| 1872 | break; |
| 1873 | case CHECK: |
| 1874 | if (state->wrap) { |
| 1875 | NEEDBITS(32); |
| 1876 | out -= left; |
| 1877 | strm->total_out += out; |
| 1878 | state->total += out; |
| 1879 | if (out) |
| 1880 | strm->adler = state->check = |
| 1881 | UPDATE(state->check, put - out, out); |
| 1882 | out = left; |
| 1883 | if (( |
| 1884 | #ifdef GUNZIP |
| 1885 | state->flags ? hold : |
| 1886 | #endif |
| 1887 | REVERSE(hold)) != state->check) { |
| 1888 | strm->msg = (char *)"incorrect data check"; |
| 1889 | state->mode = BAD; |
| 1890 | break; |
| 1891 | } |
| 1892 | INITBITS(); |
| 1893 | Tracev((stderr, "inflate: check matches trailer\n")); |
| 1894 | } |
| 1895 | #ifdef GUNZIP |
| 1896 | state->mode = LENGTH; |
| 1897 | case LENGTH: |
| 1898 | if (state->wrap && state->flags) { |
| 1899 | NEEDBITS(32); |
| 1900 | if (hold != (state->total & 0xffffffffUL)) { |
| 1901 | strm->msg = (char *)"incorrect length check"; |
| 1902 | state->mode = BAD; |
| 1903 | break; |
| 1904 | } |
| 1905 | INITBITS(); |
| 1906 | Tracev((stderr, "inflate: length matches trailer\n")); |
| 1907 | } |
| 1908 | #endif |
| 1909 | state->mode = DONE; |
| 1910 | case DONE: |
| 1911 | ret = Z_STREAM_END; |
| 1912 | goto inf_leave; |
| 1913 | case BAD: |
| 1914 | ret = Z_DATA_ERROR; |
| 1915 | goto inf_leave; |
| 1916 | case MEM: |
| 1917 | return Z_MEM_ERROR; |
| 1918 | case SYNC: |
| 1919 | default: |
| 1920 | return Z_STREAM_ERROR; |
| 1921 | } |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 1922 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1923 | /* |
| 1924 | Return from inflate(), updating the total counts and the check value. |
| 1925 | If there was no progress during the inflate() call, return a buffer |
| 1926 | error. Call updatewindow() to create and/or update the window state. |
| 1927 | Note: a memory error from inflate() is non-recoverable. |
| 1928 | */ |
| 1929 | inf_leave: |
| 1930 | RESTORE(); |
| 1931 | if (state->wsize || (state->mode < CHECK && out != strm->avail_out)) |
| 1932 | if (updatewindow(strm, out)) { |
| 1933 | state->mode = MEM; |
| 1934 | return Z_MEM_ERROR; |
| 1935 | } |
| 1936 | in -= strm->avail_in; |
| 1937 | out -= strm->avail_out; |
| 1938 | strm->total_in += in; |
| 1939 | strm->total_out += out; |
| 1940 | state->total += out; |
| 1941 | if (state->wrap && out) |
| 1942 | strm->adler = state->check = |
| 1943 | UPDATE(state->check, strm->next_out - out, out); |
| 1944 | strm->data_type = state->bits + (state->last ? 64 : 0) + |
| 1945 | (state->mode == TYPE ? 128 : 0); |
| 1946 | if (((in == 0 && out == 0) || flush == Z_FINISH) && ret == Z_OK) |
| 1947 | ret = Z_BUF_ERROR; |
| 1948 | return ret; |
Giuseppe CONDORELLI | b4a560a | 2009-07-23 04:54:45 -0400 | [diff] [blame] | 1949 | } |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1950 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1951 | int ZEXPORT inflateEnd(strm) |
| 1952 | z_streamp strm; |
| 1953 | { |
| 1954 | struct inflate_state FAR *state; |
| 1955 | if (strm == Z_NULL || strm->state == Z_NULL || strm->zfree == (free_func)0) |
| 1956 | return Z_STREAM_ERROR; |
| 1957 | state = (struct inflate_state FAR *)strm->state; |
Giuseppe CONDORELLI | 807b9be | 2009-07-29 06:05:20 -0400 | [diff] [blame] | 1958 | if (state->window != Z_NULL) { |
| 1959 | if (strm->outcb != Z_NULL) |
| 1960 | (*strm->outcb)(Z_NULL, 0); |
| 1961 | ZFREE(strm, state->window); |
| 1962 | } |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1963 | ZFREE(strm, strm->state); |
| 1964 | strm->state = Z_NULL; |
| 1965 | Tracev((stderr, "inflate: end\n")); |
| 1966 | return Z_OK; |
| 1967 | } |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 1968 | |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1969 | /*+++++*/ |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1970 | /* zutil.c -- target dependent utility functions for the compression library |
| 1971 | * Copyright (C) 1995-2005 Jean-loup Gailly. |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1972 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 1973 | */ |
| 1974 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1975 | /* @(#) $Id$ */ |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1976 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1977 | #ifndef NO_DUMMY_DECL |
| 1978 | struct internal_state {int dummy;}; /* for buggy compilers */ |
| 1979 | #endif |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 1980 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1981 | const char * const z_errmsg[10] = { |
| 1982 | "need dictionary", /* Z_NEED_DICT 2 */ |
| 1983 | "stream end", /* Z_STREAM_END 1 */ |
| 1984 | "", /* Z_OK 0 */ |
| 1985 | "file error", /* Z_ERRNO (-1) */ |
| 1986 | "stream error", /* Z_STREAM_ERROR (-2) */ |
| 1987 | "data error", /* Z_DATA_ERROR (-3) */ |
| 1988 | "insufficient memory", /* Z_MEM_ERROR (-4) */ |
| 1989 | "buffer error", /* Z_BUF_ERROR (-5) */ |
| 1990 | "incompatible version",/* Z_VERSION_ERROR (-6) */ |
| 1991 | ""}; |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 1992 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1993 | #ifdef DEBUG |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 1994 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 1995 | #ifndef verbose |
| 1996 | #define verbose 0 |
| 1997 | #endif |
| 1998 | int z_verbose = verbose; |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 1999 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 2000 | void z_error (m) |
| 2001 | char *m; |
| 2002 | { |
| 2003 | fprintf(stderr, "%s\n", m); |
Giuseppe CONDORELLI | 9041654 | 2009-09-03 07:37:46 -0400 | [diff] [blame] | 2004 | hang (); |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 2005 | } |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 2006 | #endif |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 2007 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 2008 | /* exported to allow conversion of error code to string for compress() and |
| 2009 | * uncompress() |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 2010 | */ |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 2011 | #ifndef MY_ZCALLOC /* Any system without a special alloc function */ |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 2012 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 2013 | #ifndef STDC |
| 2014 | extern voidp malloc OF((uInt size)); |
| 2015 | extern voidp calloc OF((uInt items, uInt size)); |
| 2016 | extern void free OF((voidpf ptr)); |
| 2017 | #endif |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 2018 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 2019 | voidpf zcalloc (opaque, items, size) |
| 2020 | voidpf opaque; |
| 2021 | unsigned items; |
| 2022 | unsigned size; |
| 2023 | { |
| 2024 | if (opaque) |
| 2025 | items += size - size; /* make compiler happy */ |
| 2026 | return sizeof(uInt) > 2 ? (voidpf)malloc(items * size) : |
| 2027 | (voidpf)calloc(items, size); |
| 2028 | } |
Wolfgang Denk | 72d0bca | 2009-07-24 14:24:07 +0200 | [diff] [blame] | 2029 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 2030 | void zcfree (opaque, ptr, nb) |
| 2031 | voidpf opaque; |
| 2032 | voidpf ptr; |
| 2033 | unsigned nb; |
| 2034 | { |
| 2035 | free(ptr); |
| 2036 | if (opaque) |
| 2037 | return; /* make compiler happy */ |
| 2038 | } |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 2039 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 2040 | #endif /* MY_ZCALLOC */ |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 2041 | /*+++++*/ |
| 2042 | /* adler32.c -- compute the Adler-32 checksum of a data stream |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 2043 | * Copyright (C) 1995-2004 Mark Adler |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 2044 | * For conditions of distribution and use, see copyright notice in zlib.h |
| 2045 | */ |
| 2046 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 2047 | /* @(#) $Id$ */ |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 2048 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 2049 | #define BASE 65521UL /* largest prime smaller than 65536 */ |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 2050 | #define NMAX 5552 |
| 2051 | /* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */ |
| 2052 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 2053 | #define DO1(buf,i) {adler += (buf)[i]; sum2 += adler;} |
| 2054 | #define DO2(buf,i) DO1(buf,i); DO1(buf,i+1); |
| 2055 | #define DO4(buf,i) DO2(buf,i); DO2(buf,i+2); |
| 2056 | #define DO8(buf,i) DO4(buf,i); DO4(buf,i+4); |
| 2057 | #define DO16(buf) DO8(buf,0); DO8(buf,8); |
| 2058 | |
| 2059 | /* use NO_DIVIDE if your processor does not do division in hardware */ |
| 2060 | #ifdef NO_DIVIDE |
| 2061 | #define MOD(a) \ |
| 2062 | do { \ |
| 2063 | if (a >= (BASE << 16)) \ |
| 2064 | a -= (BASE << 16); \ |
| 2065 | if (a >= (BASE << 15)) \ |
| 2066 | a -= (BASE << 15); \ |
| 2067 | if (a >= (BASE << 14)) \ |
| 2068 | a -= (BASE << 14); \ |
| 2069 | if (a >= (BASE << 13)) \ |
| 2070 | a -= (BASE << 13); \ |
| 2071 | if (a >= (BASE << 12)) \ |
| 2072 | a -= (BASE << 12); \ |
| 2073 | if (a >= (BASE << 11)) \ |
| 2074 | a -= (BASE << 11); \ |
| 2075 | if (a >= (BASE << 10)) \ |
| 2076 | a -= (BASE << 10); \ |
| 2077 | if (a >= (BASE << 9)) \ |
| 2078 | a -= (BASE << 9); \ |
| 2079 | if (a >= (BASE << 8)) \ |
| 2080 | a -= (BASE << 8); \ |
| 2081 | if (a >= (BASE << 7)) \ |
| 2082 | a -= (BASE << 7); \ |
| 2083 | if (a >= (BASE << 6)) \ |
| 2084 | a -= (BASE << 6); \ |
| 2085 | if (a >= (BASE << 5)) \ |
| 2086 | a -= (BASE << 5); \ |
| 2087 | if (a >= (BASE << 4)) \ |
| 2088 | a -= (BASE << 4); \ |
| 2089 | if (a >= (BASE << 3)) \ |
| 2090 | a -= (BASE << 3); \ |
| 2091 | if (a >= (BASE << 2)) \ |
| 2092 | a -= (BASE << 2); \ |
| 2093 | if (a >= (BASE << 1)) \ |
| 2094 | a -= (BASE << 1); \ |
| 2095 | if (a >= BASE) \ |
| 2096 | a -= BASE; \ |
| 2097 | } while (0) |
| 2098 | #define MOD4(a) \ |
| 2099 | do { \ |
| 2100 | if (a >= (BASE << 4)) \ |
| 2101 | a -= (BASE << 4); \ |
| 2102 | if (a >= (BASE << 3)) \ |
| 2103 | a -= (BASE << 3); \ |
| 2104 | if (a >= (BASE << 2)) \ |
| 2105 | a -= (BASE << 2); \ |
| 2106 | if (a >= (BASE << 1)) \ |
| 2107 | a -= (BASE << 1); \ |
| 2108 | if (a >= BASE) \ |
| 2109 | a -= BASE; \ |
| 2110 | } while (0) |
| 2111 | #else |
| 2112 | #define MOD(a) a %= BASE |
| 2113 | #define MOD4(a) a %= BASE |
| 2114 | #endif |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 2115 | |
| 2116 | /* ========================================================================= */ |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 2117 | uLong ZEXPORT adler32(adler, buf, len) |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 2118 | uLong adler; |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 2119 | const Bytef *buf; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 2120 | uInt len; |
| 2121 | { |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 2122 | unsigned long sum2; |
| 2123 | unsigned n; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 2124 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 2125 | /* split Adler-32 into component sums */ |
| 2126 | sum2 = (adler >> 16) & 0xffff; |
| 2127 | adler &= 0xffff; |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 2128 | |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 2129 | /* in case user likes doing a byte at a time, keep it fast */ |
| 2130 | if (len == 1) { |
| 2131 | adler += buf[0]; |
| 2132 | if (adler >= BASE) |
| 2133 | adler -= BASE; |
| 2134 | sum2 += adler; |
| 2135 | if (sum2 >= BASE) |
| 2136 | sum2 -= BASE; |
| 2137 | return adler | (sum2 << 16); |
Giuseppe CONDORELLI | b4a560a | 2009-07-23 04:54:45 -0400 | [diff] [blame] | 2138 | } |
Giuseppe CONDORELLI | 5e7e8e8 | 2009-07-29 08:05:08 -0400 | [diff] [blame] | 2139 | |
| 2140 | /* initial Adler-32 value (deferred check for len == 1 speed) */ |
| 2141 | if (buf == Z_NULL) |
| 2142 | return 1L; |
| 2143 | |
| 2144 | /* in case short lengths are provided, keep it somewhat fast */ |
| 2145 | if (len < 16) { |
| 2146 | while (len--) { |
| 2147 | adler += *buf++; |
| 2148 | sum2 += adler; |
| 2149 | } |
| 2150 | if (adler >= BASE) |
| 2151 | adler -= BASE; |
| 2152 | MOD4(sum2); /* only added so many BASE's */ |
| 2153 | return adler | (sum2 << 16); |
| 2154 | } |
| 2155 | |
| 2156 | /* do length NMAX blocks -- requires just one modulo operation */ |
| 2157 | while (len >= NMAX) { |
| 2158 | len -= NMAX; |
| 2159 | n = NMAX / 16; /* NMAX is divisible by 16 */ |
| 2160 | do { |
| 2161 | DO16(buf); /* 16 sums unrolled */ |
| 2162 | buf += 16; |
| 2163 | } while (--n); |
| 2164 | MOD(adler); |
| 2165 | MOD(sum2); |
| 2166 | } |
| 2167 | |
| 2168 | /* do remaining bytes (less than NMAX, still just one modulo) */ |
| 2169 | if (len) { /* avoid modulos if none remaining */ |
| 2170 | while (len >= 16) { |
| 2171 | len -= 16; |
| 2172 | DO16(buf); |
| 2173 | buf += 16; |
| 2174 | } |
| 2175 | while (len--) { |
| 2176 | adler += *buf++; |
| 2177 | sum2 += adler; |
| 2178 | } |
| 2179 | MOD(adler); |
| 2180 | MOD(sum2); |
| 2181 | } |
| 2182 | |
| 2183 | /* return recombined sums */ |
| 2184 | return adler | (sum2 << 16); |
wdenk | 4a5b6a3 | 2001-04-28 17:59:11 +0000 | [diff] [blame] | 2185 | } |