19e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project/* inflate.h -- internal inflate state definition 2381716e9396b55b1adb8235b020c37344f60ab07Elliott Hughes * Copyright (C) 1995-2009 Mark Adler 39e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project * For conditions of distribution and use, see copyright notice in zlib.h 49e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project */ 59e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project 69e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project/* WARNING: this file should *not* be used by applications. It is 79e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project part of the implementation of the compression library and is 89e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project subject to change. Applications should only use zlib.h. 99e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project */ 109e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project 119e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project/* define NO_GZIP when compiling if you want to disable gzip header and 129e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project trailer decoding by inflate(). NO_GZIP would be used to avoid linking in 139e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project the crc code when it is not needed. For shared libraries, gzip decoding 149e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project should be left enabled. */ 159e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project#ifndef NO_GZIP 169e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project# define GUNZIP 179e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project#endif 189e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project 199e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project/* Possible inflate modes between inflate() calls */ 209e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Projecttypedef enum { 219e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project HEAD, /* i: waiting for magic header */ 229e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project FLAGS, /* i: waiting for method and flags (gzip) */ 239e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project TIME, /* i: waiting for modification time (gzip) */ 249e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project OS, /* i: waiting for extra flags and operating system (gzip) */ 259e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project EXLEN, /* i: waiting for extra length (gzip) */ 269e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project EXTRA, /* i: waiting for extra bytes (gzip) */ 279e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project NAME, /* i: waiting for end of file name (gzip) */ 289e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project COMMENT, /* i: waiting for end of comment (gzip) */ 299e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project HCRC, /* i: waiting for header crc (gzip) */ 309e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project DICTID, /* i: waiting for dictionary check value */ 319e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project DICT, /* waiting for inflateSetDictionary() call */ 329e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project TYPE, /* i: waiting for type bits, including last-flag bit */ 339e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project TYPEDO, /* i: same, but skip check to exit inflate on new block */ 349e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project STORED, /* i: waiting for stored size (length and complement) */ 35381716e9396b55b1adb8235b020c37344f60ab07Elliott Hughes COPY_, /* i/o: same as COPY below, but only first time in */ 369e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project COPY, /* i/o: waiting for input or output to copy stored block */ 379e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project TABLE, /* i: waiting for dynamic block table lengths */ 389e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project LENLENS, /* i: waiting for code length code lengths */ 399e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project CODELENS, /* i: waiting for length/lit and distance code lengths */ 40381716e9396b55b1adb8235b020c37344f60ab07Elliott Hughes LEN_, /* i: same as LEN below, but only first time in */ 41381716e9396b55b1adb8235b020c37344f60ab07Elliott Hughes LEN, /* i: waiting for length/lit/eob code */ 429e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project LENEXT, /* i: waiting for length extra bits */ 439e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project DIST, /* i: waiting for distance code */ 449e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project DISTEXT, /* i: waiting for distance extra bits */ 459e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project MATCH, /* o: waiting for output space to copy string */ 469e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project LIT, /* o: waiting for output space to write literal */ 479e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project CHECK, /* i: waiting for 32-bit check value */ 489e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project LENGTH, /* i: waiting for 32-bit length (gzip) */ 499e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project DONE, /* finished check, done -- remain here until reset */ 509e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project BAD, /* got a data error -- remain here until reset */ 519e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project MEM, /* got an inflate() memory error -- remain here until reset */ 529e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project SYNC /* looking for synchronization bytes to restart inflate() */ 539e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project} inflate_mode; 549e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project 559e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project/* 569e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project State transitions between above modes - 579e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project 58381716e9396b55b1adb8235b020c37344f60ab07Elliott Hughes (most modes can go to BAD or MEM on error -- not shown for clarity) 599e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project 609e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project Process header: 61381716e9396b55b1adb8235b020c37344f60ab07Elliott Hughes HEAD -> (gzip) or (zlib) or (raw) 62381716e9396b55b1adb8235b020c37344f60ab07Elliott Hughes (gzip) -> FLAGS -> TIME -> OS -> EXLEN -> EXTRA -> NAME -> COMMENT -> 63381716e9396b55b1adb8235b020c37344f60ab07Elliott Hughes HCRC -> TYPE 649e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project (zlib) -> DICTID or TYPE 659e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project DICTID -> DICT -> TYPE 66381716e9396b55b1adb8235b020c37344f60ab07Elliott Hughes (raw) -> TYPEDO 679e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project Read deflate blocks: 68381716e9396b55b1adb8235b020c37344f60ab07Elliott Hughes TYPE -> TYPEDO -> STORED or TABLE or LEN_ or CHECK 69381716e9396b55b1adb8235b020c37344f60ab07Elliott Hughes STORED -> COPY_ -> COPY -> TYPE 70381716e9396b55b1adb8235b020c37344f60ab07Elliott Hughes TABLE -> LENLENS -> CODELENS -> LEN_ 71381716e9396b55b1adb8235b020c37344f60ab07Elliott Hughes LEN_ -> LEN 72381716e9396b55b1adb8235b020c37344f60ab07Elliott Hughes Read deflate codes in fixed or dynamic block: 739e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project LEN -> LENEXT or LIT or TYPE 749e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project LENEXT -> DIST -> DISTEXT -> MATCH -> LEN 759e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project LIT -> LEN 769e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project Process trailer: 779e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project CHECK -> LENGTH -> DONE 789e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project */ 799e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project 80381716e9396b55b1adb8235b020c37344f60ab07Elliott Hughes/* state maintained between inflate() calls. Approximately 10K bytes. */ 819e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Projectstruct inflate_state { 829e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project inflate_mode mode; /* current inflate mode */ 839e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project int last; /* true if processing last block */ 849e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project int wrap; /* bit 0 true for zlib, bit 1 true for gzip */ 859e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project int havedict; /* true if dictionary provided */ 869e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project int flags; /* gzip header method and flags (0 if zlib) */ 879e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned dmax; /* zlib header max distance (INFLATE_STRICT) */ 889e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned long check; /* protected copy of check value */ 899e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned long total; /* protected copy of output count */ 909e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project gz_headerp head; /* where to save gzip header information */ 919e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project /* sliding window */ 929e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned wbits; /* log base 2 of requested window size */ 939e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned wsize; /* window size or zero if not using window */ 949e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned whave; /* valid bytes in the window */ 95381716e9396b55b1adb8235b020c37344f60ab07Elliott Hughes unsigned wnext; /* window write index */ 969e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned char FAR *window; /* allocated sliding window, if needed */ 979e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project /* bit accumulator */ 989e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned long hold; /* input bit accumulator */ 999e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned bits; /* number of bits in "in" */ 1009e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project /* for string and stored block copying */ 1019e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned length; /* literal or length of data to copy */ 1029e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned offset; /* distance back to copy string from */ 1039e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project /* for table and code decoding */ 1049e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned extra; /* extra bits needed */ 1059e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project /* fixed and dynamic code tables */ 1069e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project code const FAR *lencode; /* starting table for length/literal codes */ 1079e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project code const FAR *distcode; /* starting table for distance codes */ 1089e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned lenbits; /* index bits for lencode */ 1099e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned distbits; /* index bits for distcode */ 1109e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project /* dynamic table building */ 1119e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned ncode; /* number of code length code lengths */ 1129e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned nlen; /* number of length code lengths */ 1139e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned ndist; /* number of distance code lengths */ 1149e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned have; /* number of code lengths in lens[] */ 1159e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project code FAR *next; /* next available space in codes[] */ 1169e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned short lens[320]; /* temporary storage for code lengths */ 1179e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project unsigned short work[288]; /* work area for code table building */ 1189e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project code codes[ENOUGH]; /* space for code tables */ 119381716e9396b55b1adb8235b020c37344f60ab07Elliott Hughes int sane; /* if false, allow invalid distance too far */ 120381716e9396b55b1adb8235b020c37344f60ab07Elliott Hughes int back; /* bits back of last unprocessed length/lit */ 121381716e9396b55b1adb8235b020c37344f60ab07Elliott Hughes unsigned was; /* initial length of match */ 1229e38dfa2f95fce609707a0941f10af9a785288deThe Android Open Source Project}; 123