1322 lines
		
	
	
		
			43 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			1322 lines
		
	
	
		
			43 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /*
 | ||
|  |  * inflate.c -  inflate decompression routine | ||
|  |  * | ||
|  |  * Version 1.1.2 | ||
|  |  */ | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Copyright (C) 1995, Edward B. Hamrick | ||
|  |  * | ||
|  |  * Permission to use, copy, modify, and distribute this software and | ||
|  |  * its documentation for any purpose and without fee is hereby granted, | ||
|  |  * provided that the above copyright notice appear in all copies and | ||
|  |  * that both that copyright notice and this permission notice appear in | ||
|  |  * supporting documentation, and that the name of the copyright holders | ||
|  |  * not be used in advertising or publicity pertaining to distribution of | ||
|  |  * the software without specific, written prior permission. The copyright | ||
|  |  * holders makes no representations about the suitability of this software | ||
|  |  * for any purpose. It is provided "as is" without express or implied warranty. | ||
|  |  * | ||
|  |  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS | ||
|  |  * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, | ||
|  |  * IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT | ||
|  |  * OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF | ||
|  |  * USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER | ||
|  |  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE | ||
|  |  * OF THIS SOFTWARE. | ||
|  |  */ | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Changes from 1.1 to 1.1.2: | ||
|  |  * Relicensed under the MIT license, with consent of the copyright holders. | ||
|  |  * Claudio Matsuoka (Jan 11 2011) | ||
|  |  */ | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * inflate.c is based on the public-domain (non-copyrighted) version | ||
|  |  * written by Mark Adler, version c14o, 23 August 1994.  It has been  | ||
|  |  * modified to be reentrant, more portable, and to be data driven. | ||
|  |  */ | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * 1) All file i/o is done externally to these routines | ||
|  |  * 2) Routines are symmetrical so inflate can feed into deflate | ||
|  |  * 3) Routines can be easily integrated into wide range of applications | ||
|  |  * 4) Routines are very portable, and use only ANSI C | ||
|  |  * 5) No #defines in inflate.h to conflict with external #defines | ||
|  |  * 6) No external routines need be called by these routines | ||
|  |  * 7) Buffers are owned by the calling routine | ||
|  |  * 8) No static non-constant variables are allowed | ||
|  |  */ | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Note that for each call to InflatePutBuffer, there will be | ||
|  |  * 0 or more calls to (*putbuffer_ptr).  Before InflatePutBuffer | ||
|  |  * returns, it will have output as much uncompressed data as | ||
|  |  * is possible. | ||
|  |  */ | ||
|  | 
 | ||
|  | #ifdef MEMCPY
 | ||
|  | #include <mem.h>
 | ||
|  | #endif
 | ||
|  | 
 | ||
|  | #include "inflate.h"
 | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Macros for constants | ||
|  |  */ | ||
|  | 
 | ||
|  | #ifndef NULL
 | ||
|  | #define NULL ((void *) 0)
 | ||
|  | #endif
 | ||
|  | 
 | ||
|  | #ifndef TRUE
 | ||
|  | #define TRUE 1
 | ||
|  | #endif
 | ||
|  | 
 | ||
|  | #ifndef FALSE
 | ||
|  | #define FALSE 0
 | ||
|  | #endif
 | ||
|  | 
 | ||
|  | #ifndef WINDOWSIZE
 | ||
|  | #define WINDOWSIZE 0x8000
 | ||
|  | #endif
 | ||
|  | 
 | ||
|  | #ifndef WINDOWMASK
 | ||
|  | #define WINDOWMASK 0x7fff
 | ||
|  | #endif
 | ||
|  | 
 | ||
|  | #ifndef BUFFERSIZE
 | ||
|  | #define BUFFERSIZE 0x4000
 | ||
|  | #endif
 | ||
|  | 
 | ||
|  | #ifndef BUFFERMASK
 | ||
|  | #define BUFFERMASK 0x3fff
 | ||
|  | #endif
 | ||
|  | 
 | ||
|  | #ifndef INFLATESTATETYPE
 | ||
|  | #define INFLATESTATETYPE   0xabcdabcdL
 | ||
|  | #endif
 | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * typedefs | ||
|  |  */ | ||
|  | 
 | ||
|  | typedef unsigned long  ulg; | ||
|  | typedef unsigned short ush; | ||
|  | typedef unsigned char  uch; | ||
|  | 
 | ||
|  | /* Structure to hold state for inflating zip files */ | ||
|  | struct InflateState { | ||
|  | 
 | ||
|  |   unsigned long  runtimetypeid1;             /* to detect run-time errors  */ | ||
|  |   int            errorencountered;           /* error encountered flag     */ | ||
|  | 
 | ||
|  |   /* Decoding state */ | ||
|  |   int            state;                      /* -1 -> need block type      */ | ||
|  |                                              /*  0 -> need stored setup    */ | ||
|  |                                              /*  1 -> need fixed setup     */ | ||
|  |                                              /*  2 -> need dynamic setup   */ | ||
|  |                                              /* 10 -> need stored data     */ | ||
|  |                                              /* 11 -> need fixed data      */ | ||
|  |                                              /* 12 -> need dynamic data    */ | ||
|  | 
 | ||
|  | /* State for decoding fixed & dynamic data */ | ||
|  |   struct huft   *tl;                         /* literal/length decoder tbl */ | ||
|  |   struct huft   *td;                         /* distance decoder table     */ | ||
|  |   int            bl;                         /* bits decoded by tl         */ | ||
|  |   int            bd;                         /* bits decoded by td         */ | ||
|  | 
 | ||
|  |   /* State for decoding stored data */ | ||
|  |   unsigned int   storelength; | ||
|  | 
 | ||
|  |   /* State to keep track that last block has been encountered */ | ||
|  |   int            lastblock;                  /* current block is last      */ | ||
|  | 
 | ||
|  |   /* Input buffer state (circular) */ | ||
|  |   ulg            bb;                         /* input buffer bits          */ | ||
|  |   unsigned int   bk;                         /* input buffer count of bits */ | ||
|  |   unsigned int   bp;                         /* input buffer pointer       */ | ||
|  |   unsigned int   bs;                         /* input buffer size          */ | ||
|  |   unsigned char  buffer[BUFFERSIZE];         /* input buffer data          */ | ||
|  | 
 | ||
|  |   /* Storage for try/catch */ | ||
|  |   ulg            catch_bb;                   /* bit buffer                 */ | ||
|  |   unsigned int   catch_bk;                   /* bits in bit buffer         */ | ||
|  |   unsigned int   catch_bp;                   /* buffer pointer             */ | ||
|  |   unsigned int   catch_bs;                   /* buffer size                */ | ||
|  | 
 | ||
|  |   /* Output window state (circular) */ | ||
|  |   unsigned int   wp;                         /* output window pointer      */ | ||
|  |   unsigned int   wf;                         /* output window flush-from   */ | ||
|  |   unsigned char  window[WINDOWSIZE];         /* output window data         */ | ||
|  | 
 | ||
|  |   /* Application state */ | ||
|  |   void          *AppState;                   /* opaque ptr for callout     */ | ||
|  | 
 | ||
|  |   /* pointers to call-outs */ | ||
|  |   int (*putbuffer_ptr)(                      /* returns 0 on success       */ | ||
|  |     void *AppState,                          /* opaque ptr from Initialize */ | ||
|  |     unsigned char *buffer,                   /* buffer to put              */ | ||
|  |     long length                              /* length of buffer           */ | ||
|  |   ); | ||
|  | 
 | ||
|  |   void *(*malloc_ptr)(long length);          /* utility routine            */ | ||
|  | 
 | ||
|  |   void (*free_ptr)(void *buffer);            /* utility routine            */ | ||
|  | 
 | ||
|  |   unsigned long  runtimetypeid2;             /* to detect run-time errors  */ | ||
|  | }; | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Error handling macro | ||
|  |  */ | ||
|  | 
 | ||
|  | #define ERROREXIT(is) {(is)->errorencountered = TRUE; return TRUE;}
 | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Macros for handling data in the input buffer | ||
|  |  * | ||
|  |  * Note that the NEEDBITS and DUMPBITS macros | ||
|  |  * need to be bracketed by the TRY/CATCH macros | ||
|  |  * | ||
|  |  * The usage is: | ||
|  |  * | ||
|  |  *      TRY | ||
|  |  *      { | ||
|  |  *        NEEDBITS(j) | ||
|  |  *        x = b & mask_bits[j]; | ||
|  |  *        DUMPBITS(j) | ||
|  |  *      } | ||
|  |  *      CATCH_BEGIN | ||
|  |  *        cleanup code | ||
|  |  *      CATCH_END | ||
|  |  * | ||
|  |  * Note that there can only be one TRY/CATCH pair per routine | ||
|  |  * because of the use of goto in the implementation of the macros. | ||
|  |  * | ||
|  |  * NEEDBITS makes sure that b has at least j bits in it, and | ||
|  |  * DUMPBITS removes the bits from b.  The macros use the variable k | ||
|  |  * for the number of bits in b.  Normally, b and k are register | ||
|  |  * variables for speed, and are initialized at the beginning of a | ||
|  |  * routine that uses these macros from a global bit buffer and count. | ||
|  |  * | ||
|  |  * In order to not ask for more bits than there are in the compressed | ||
|  |  * stream, the Huffman tables are constructed to only ask for just | ||
|  |  * enough bits to make up the end-of-block code (value 256).  Then no | ||
|  |  * bytes need to be "returned" to the buffer at the end of the last | ||
|  |  * block.  See the huft_build() routine. | ||
|  |  */ | ||
|  | 
 | ||
|  | #define TRY              \
 | ||
|  |   is->catch_bb = b;      \ | ||
|  |   is->catch_bk = k;      \ | ||
|  |   is->catch_bp = is->bp; \ | ||
|  |   is->catch_bs = is->bs; | ||
|  | 
 | ||
|  | #define CATCH_BEGIN      \
 | ||
|  |   goto cleanup_done;     \ | ||
|  |   cleanup:               \ | ||
|  |   b      = is->catch_bb; \ | ||
|  |   k      = is->catch_bk; \ | ||
|  |   is->bb = b;            \ | ||
|  |   is->bk = k;            \ | ||
|  |   is->bp = is->catch_bp; \ | ||
|  |   is->bs = is->catch_bs; | ||
|  | 
 | ||
|  | #define CATCH_END \
 | ||
|  |   cleanup_done: ; | ||
|  | 
 | ||
|  | #define NEEDBITS(n)                                      \
 | ||
|  | {                                                        \ | ||
|  |   while (k < (n))                                        \ | ||
|  |   {                                                      \ | ||
|  |     if (is->bs <= 0)                                     \ | ||
|  |     {                                                    \ | ||
|  |       goto cleanup;                                      \ | ||
|  |     }                                                    \ | ||
|  |     b |= ((ulg) (is->buffer[is->bp & BUFFERMASK])) << k; \ | ||
|  |     is->bs--;                                            \ | ||
|  |     is->bp++;                                            \ | ||
|  |     k += 8;                                              \ | ||
|  |   }                                                      \ | ||
|  | } | ||
|  | 
 | ||
|  | #define DUMPBITS(n) \
 | ||
|  | {                   \ | ||
|  |   b >>= (n);        \ | ||
|  |   k -= (n);         \ | ||
|  | } | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Macro for flushing the output window to the putbuffer callout. | ||
|  |  * | ||
|  |  * Note that the window is always flushed when it fills to 32K, | ||
|  |  * and before returning to the application. | ||
|  |  */ | ||
|  | 
 | ||
|  | #define FLUSHWINDOW(w, now)                               \
 | ||
|  | if ((now && (is->wp > is->wf)) || ((w) >= WINDOWSIZE))    \ | ||
|  | {                                                         \ | ||
|  |   is->wp = (w);                                           \ | ||
|  |   if ((*(is->putbuffer_ptr))                              \ | ||
|  |         (is->AppState, is->window+is->wf, is->wp-is->wf)) \ | ||
|  |     ERROREXIT(is);                                        \ | ||
|  |   is->wp &= WINDOWMASK;                                   \ | ||
|  |   is->wf  = is->wp;                                       \ | ||
|  |   (w) = is->wp;                                           \ | ||
|  | } | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Inflate deflated (PKZIP's method 8 compressed) data.  The compression | ||
|  |  * method searches for as much of the current string of bytes (up to a | ||
|  |  * length of 258) in the previous 32K bytes.  If it doesn't find any | ||
|  |  * matches (of at least length 3), it codes the next byte.  Otherwise, it | ||
|  |  * codes the length of the matched string and its distance backwards from | ||
|  |  * the current position.  There is a single Huffman code that codes both | ||
|  |  * single bytes (called "literals") and match lengths.  A second Huffman | ||
|  |  * code codes the distance information, which follows a length code.  Each | ||
|  |  * length or distance code actually represents a base value and a number | ||
|  |  * of "extra" (sometimes zero) bits to get to add to the base value.  At | ||
|  |  * the end of each deflated block is a special end-of-block (EOB) literal/ | ||
|  |  * length code.  The decoding process is basically: get a literal/length | ||
|  |  * code; if EOB then done; if a literal, emit the decoded byte; if a | ||
|  |  * length then get the distance and emit the referred-to bytes from the | ||
|  |  * sliding window of previously emitted data. | ||
|  |  * | ||
|  |  * There are (currently) three kinds of inflate blocks: stored, fixed, and | ||
|  |  * dynamic.  The compressor outputs a chunk of data at a time and decides | ||
|  |  * which method to use on a chunk-by-chunk basis.  A chunk might typically | ||
|  |  * be 32K to 64K, uncompressed.  If the chunk is uncompressible, then the | ||
|  |  * "stored" method is used.  In this case, the bytes are simply stored as | ||
|  |  * is, eight bits per byte, with none of the above coding.  The bytes are | ||
|  |  * preceded by a count, since there is no longer an EOB code. | ||
|  |  * | ||
|  |  * If the data is compressible, then either the fixed or dynamic methods | ||
|  |  * are used.  In the dynamic method, the compressed data is preceded by | ||
|  |  * an encoding of the literal/length and distance Huffman codes that are | ||
|  |  * to be used to decode this block.  The representation is itself Huffman | ||
|  |  * coded, and so is preceded by a description of that code.  These code | ||
|  |  * descriptions take up a little space, and so for small blocks, there is | ||
|  |  * a predefined set of codes, called the fixed codes.  The fixed method is | ||
|  |  * used if the block ends up smaller that way (usually for quite small | ||
|  |  * chunks); otherwise the dynamic method is used.  In the latter case, the | ||
|  |  * codes are customized to the probabilities in the current block and so | ||
|  |  * can code it much better than the pre-determined fixed codes can. | ||
|  |  * | ||
|  |  * The Huffman codes themselves are decoded using a mutli-level table | ||
|  |  * lookup, in order to maximize the speed of decoding plus the speed of | ||
|  |  * building the decoding tables.  See the comments below that precede the | ||
|  |  * lbits and dbits tuning parameters. | ||
|  |  */ | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Notes beyond the 1.93a appnote.txt: | ||
|  |  * | ||
|  |  * 1. Distance pointers never point before the beginning of the output | ||
|  |  *    stream. | ||
|  |  * 2. Distance pointers can point back across blocks, up to 32k away. | ||
|  |  * 3. There is an implied maximum of 7 bits for the bit length table and | ||
|  |  *    15 bits for the actual data. | ||
|  |  * 4. If only one code exists, then it is encoded using one bit.  (Zero | ||
|  |  *    would be more efficient, but perhaps a little confusing.)  If two | ||
|  |  *    codes exist, they are coded using one bit each (0 and 1). | ||
|  |  * 5. There is no way of sending zero distance codes--a dummy must be | ||
|  |  *    sent if there are none.  (History: a pre 2.0 version of PKZIP would | ||
|  |  *    store blocks with no distance codes, but this was discovered to be | ||
|  |  *    too harsh a criterion.)  Valid only for 1.93a.  2.04c does allow | ||
|  |  *    zero distance codes, which is sent as one code of zero bits in | ||
|  |  *    length. | ||
|  |  * 6. There are up to 286 literal/length codes.  Code 256 represents the | ||
|  |  *    end-of-block.  Note however that the static length tree defines | ||
|  |  *    288 codes just to fill out the Huffman codes.  Codes 286 and 287 | ||
|  |  *    cannot be used though, since there is no length base or extra bits | ||
|  |  *    defined for them.  Similarly, there are up to 30 distance codes. | ||
|  |  *    However, static trees define 32 codes (all 5 bits) to fill out the | ||
|  |  *    Huffman codes, but the last two had better not show up in the data. | ||
|  |  * 7. Unzip can check dynamic Huffman blocks for complete code sets. | ||
|  |  *    The exception is that a single code would not be complete (see #4). | ||
|  |  * 8. The five bits following the block type is really the number of | ||
|  |  *    literal codes sent minus 257. | ||
|  |  * 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits | ||
|  |  *    (1+6+6).  Therefore, to output three times the length, you output | ||
|  |  *    three codes (1+1+1), whereas to output four times the same length, | ||
|  |  *    you only need two codes (1+3).  Hmm. | ||
|  |  *10. In the tree reconstruction algorithm, Code = Code + Increment | ||
|  |  *    only if BitLength(i) is not zero.  (Pretty obvious.) | ||
|  |  *11. Correction: 4 Bits: # of Bit Length codes - 4     (4 - 19) | ||
|  |  *12. Note: length code 284 can represent 227-258, but length code 285 | ||
|  |  *    really is 258.  The last length deserves its own, short code | ||
|  |  *    since it gets used a lot in very redundant files.  The length | ||
|  |  *    258 is special since 258 - 3 (the min match length) is 255. | ||
|  |  *13. The literal/length and distance code bit lengths are read as a | ||
|  |  *    single stream of lengths.  It is possible (and advantageous) for | ||
|  |  *    a repeat code (16, 17, or 18) to go across the boundary between | ||
|  |  *    the two sets of lengths. | ||
|  |  */ | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Huffman code lookup table entry--this entry is four bytes for machines | ||
|  |  * that have 16-bit pointers (e.g. PC's in the small or medium model). | ||
|  |  * Valid extra bits are 0..13.  e == 15 is EOB (end of block), e == 16 | ||
|  |  * means that v is a literal, 16 < e < 32 means that v is a pointer to | ||
|  |  * the next table, which codes e - 16 bits, and lastly e == 99 indicates | ||
|  |  * an unused code.  If a code with e == 99 is looked up, this implies an | ||
|  |  * error in the data. | ||
|  |  */ | ||
|  | 
 | ||
|  | struct huft { | ||
|  |   uch e;                /* number of extra bits or operation */ | ||
|  |   uch b;                /* number of bits in this code or subcode */ | ||
|  |   union { | ||
|  |     ush n;              /* literal, length base, or distance base */ | ||
|  |     struct huft *t;     /* pointer to next level of table */ | ||
|  |   } v; | ||
|  | }; | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Tables for deflate from PKZIP's appnote.txt. | ||
|  |  */ | ||
|  | 
 | ||
|  | static const unsigned border[] = { /* Order of the bit length code lengths */ | ||
|  |         16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; | ||
|  | 
 | ||
|  | static const ush cplens[] = {      /* Copy lengths for literal codes 257..285 */ | ||
|  |         3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, | ||
|  |         35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0}; | ||
|  |         /* note: see note #13 above about the 258 in this list. */ | ||
|  | 
 | ||
|  | static const ush cplext[] = {      /* Extra bits for literal codes 257..285 */ | ||
|  |         0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, | ||
|  |         3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 99, 99}; /* 99==invalid */ | ||
|  | 
 | ||
|  | static const ush cpdist[] = {      /* Copy offsets for distance codes 0..29 */ | ||
|  |         1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, | ||
|  |         257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, | ||
|  |         8193, 12289, 16385, 24577}; | ||
|  | 
 | ||
|  | static const ush cpdext[] = {      /* Extra bits for distance codes */ | ||
|  |         0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, | ||
|  |         7, 7, 8, 8, 9, 9, 10, 10, 11, 11, | ||
|  |         12, 12, 13, 13}; | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Constants for run-time computation of mask | ||
|  |  */ | ||
|  | 
 | ||
|  | static const ush mask_bits[] = { | ||
|  |     0x0000, | ||
|  |     0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff, | ||
|  |     0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff | ||
|  | }; | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Huffman code decoding is performed using a multi-level table lookup. | ||
|  |  * The fastest way to decode is to simply build a lookup table whose | ||
|  |  * size is determined by the longest code.  However, the time it takes | ||
|  |  * to build this table can also be a factor if the data being decoded | ||
|  |  * is not very long.  The most common codes are necessarily the | ||
|  |  * shortest codes, so those codes dominate the decoding time, and hence | ||
|  |  * the speed.  The idea is you can have a shorter table that decodes the | ||
|  |  * shorter, more probable codes, and then point to subsidiary tables for | ||
|  |  * the longer codes.  The time it costs to decode the longer codes is | ||
|  |  * then traded against the time it takes to make longer tables. | ||
|  |  * | ||
|  |  * This results of this trade are in the variables lbits and dbits | ||
|  |  * below.  lbits is the number of bits the first level table for literal/ | ||
|  |  * length codes can decode in one step, and dbits is the same thing for | ||
|  |  * the distance codes.  Subsequent tables are also less than or equal to | ||
|  |  * those sizes.  These values may be adjusted either when all of the | ||
|  |  * codes are shorter than that, in which case the longest code length in | ||
|  |  * bits is used, or when the shortest code is *longer* than the requested | ||
|  |  * table size, in which case the length of the shortest code in bits is | ||
|  |  * used. | ||
|  |  * | ||
|  |  * There are two different values for the two tables, since they code a | ||
|  |  * different number of possibilities each.  The literal/length table | ||
|  |  * codes 286 possible values, or in a flat code, a little over eight | ||
|  |  * bits.  The distance table codes 30 possible values, or a little less | ||
|  |  * than five bits, flat.  The optimum values for speed end up being | ||
|  |  * about one bit more than those, so lbits is 8+1 and dbits is 5+1. | ||
|  |  * The optimum values may differ though from machine to machine, and | ||
|  |  * possibly even between compilers.  Your mileage may vary. | ||
|  |  */ | ||
|  | 
 | ||
|  | static const int lbits = 9;  /* bits in base literal/length lookup table */ | ||
|  | static const int dbits = 6;  /* bits in base distance lookup table */ | ||
|  | 
 | ||
|  | /* If BMAX needs to be larger than 16, then h and x[] should be ulg. */ | ||
|  | #define BMAX 16         /* maximum bit length of any code (16 for explode) */
 | ||
|  | #define N_MAX 288       /* maximum number of codes in any set */
 | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Free the malloc'ed tables built by huft_build(), which makes a linked | ||
|  |  * list of the tables it made, with the links in a dummy first entry of | ||
|  |  * each table. | ||
|  |  */ | ||
|  | 
 | ||
|  | static int huft_free( | ||
|  |   struct InflateState *is, /* Inflate state */ | ||
|  |   struct huft *t           /* table to free */ | ||
|  | ) | ||
|  | { | ||
|  |   struct huft *p, *q; | ||
|  | 
 | ||
|  |   /* Go through linked list, freeing from the malloced (t[-1]) address. */ | ||
|  |   p = t; | ||
|  |   while (p != (struct huft *)NULL) | ||
|  |   { | ||
|  |     q = (--p)->v.t; | ||
|  |     (*is->free_ptr)((char*)p); | ||
|  |     p = q; | ||
|  |   } | ||
|  |   return 0; | ||
|  | } | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Given a list of code lengths and a maximum table size, make a set of | ||
|  |  * tables to decode that set of codes.  Return zero on success, one if | ||
|  |  * the given code set is incomplete (the tables are still built in this | ||
|  |  * case), two if the input is invalid (all zero length codes or an | ||
|  |  * oversubscribed set of lengths), and three if not enough memory. | ||
|  |  * The code with value 256 is special, and the tables are constructed | ||
|  |  * so that no bits beyond that code are fetched when that code is | ||
|  |  * decoded. | ||
|  |  */ | ||
|  | 
 | ||
|  | static int huft_build( | ||
|  |   struct InflateState *is, /* Inflate state */ | ||
|  |   unsigned *b,             /* code lengths in bits (all assumed <= BMAX) */ | ||
|  |   unsigned n,              /* number of codes (assumed <= N_MAX) */ | ||
|  |   unsigned s,              /* number of simple-valued codes (0..s-1) */ | ||
|  |   const ush *d,            /* list of base values for non-simple codes */ | ||
|  |   const ush *e,            /* list of extra bits for non-simple codes */ | ||
|  |   struct huft **t,         /* result: starting table */ | ||
|  |   int *m                   /* maximum lookup bits, returns actual */ | ||
|  | ) | ||
|  | { | ||
|  |   unsigned a;                   /* counter for codes of length k */ | ||
|  |   unsigned c[BMAX+1];           /* bit length count table */ | ||
|  |   unsigned el;                  /* length of EOB code (value 256) */ | ||
|  |   unsigned f;                   /* i repeats in table every f entries */ | ||
|  |   int g;                        /* maximum code length */ | ||
|  |   int h;                        /* table level */ | ||
|  |   unsigned i;                   /* counter, current code */ | ||
|  |   unsigned j;                   /* counter */ | ||
|  |   int k;                        /* number of bits in current code */ | ||
|  |   int lx[BMAX+1];               /* memory for l[-1..BMAX-1] */ | ||
|  |   int *l = lx+1;                /* stack of bits per table */ | ||
|  |   unsigned *p;                  /* pointer into c[], b[], or v[] */ | ||
|  |   struct huft *q;               /* points to current table */ | ||
|  |   struct huft r;                /* table entry for structure assignment */ | ||
|  |   struct huft *u[BMAX];         /* table stack */ | ||
|  |   unsigned v[N_MAX];            /* values in order of bit length */ | ||
|  |   int w;                        /* bits before this table == (l * h) */ | ||
|  |   unsigned x[BMAX+1];           /* bit offsets, then code stack */ | ||
|  |   unsigned *xp;                 /* pointer into x */ | ||
|  |   int y;                        /* number of dummy codes added */ | ||
|  |   unsigned z;                   /* number of entries in current table */ | ||
|  | 
 | ||
|  |   /* clear the bit length count table */ | ||
|  |   for (i=0; i<(BMAX+1); i++) | ||
|  |   { | ||
|  |     c[i] = 0; | ||
|  |   } | ||
|  | 
 | ||
|  |   /* Generate counts for each bit length */ | ||
|  |   el = n > 256 ? b[256] : BMAX; /* set length of EOB code, if any */ | ||
|  |   p = b;  i = n; | ||
|  |   do { | ||
|  |     c[*p]++; p++;               /* assume all entries <= BMAX */ | ||
|  |   } while (--i); | ||
|  |   if (c[0] == n)                /* null input--all zero length codes */ | ||
|  |   { | ||
|  |     *t = (struct huft *)NULL; | ||
|  |     *m = 0; | ||
|  |     return 0; | ||
|  |   } | ||
|  | 
 | ||
|  |   /* Find minimum and maximum length, bound *m by those */ | ||
|  |   for (j = 1; j <= BMAX; j++) | ||
|  |     if (c[j]) | ||
|  |       break; | ||
|  |   k = j;                        /* minimum code length */ | ||
|  |   if ((unsigned)*m < j) | ||
|  |     *m = j; | ||
|  |   for (i = BMAX; i; i--) | ||
|  |     if (c[i]) | ||
|  |       break; | ||
|  |   g = i;                        /* maximum code length */ | ||
|  |   if ((unsigned)*m > i) | ||
|  |     *m = i; | ||
|  | 
 | ||
|  |   /* Adjust last length count to fill out codes, if needed */ | ||
|  |   for (y = 1 << j; j < i; j++, y <<= 1) | ||
|  |     if ((y -= c[j]) < 0) | ||
|  |       return 2;                 /* bad input: more codes than bits */ | ||
|  |   if ((y -= c[i]) < 0) | ||
|  |     return 2; | ||
|  |   c[i] += y; | ||
|  | 
 | ||
|  |   /* Generate starting offsets into the value table for each length */ | ||
|  |   x[1] = j = 0; | ||
|  |   p = c + 1;  xp = x + 2; | ||
|  |   while (--i) {                 /* note that i == g from above */ | ||
|  |     *xp++ = (j += *p++); | ||
|  |   } | ||
|  | 
 | ||
|  |   /* Make a table of values in order of bit lengths */ | ||
|  |   p = b;  i = 0; | ||
|  |   do { | ||
|  |     if ((j = *p++) != 0) | ||
|  |       v[x[j]++] = i; | ||
|  |   } while (++i < n); | ||
|  | 
 | ||
|  |   /* Generate the Huffman codes and for each, make the table entries */ | ||
|  |   x[0] = i = 0;                 /* first Huffman code is zero */ | ||
|  |   p = v;                        /* grab values in bit order */ | ||
|  |   h = -1;                       /* no tables yet--level -1 */ | ||
|  |   w = l[-1] = 0;                /* no bits decoded yet */ | ||
|  |   u[0] = (struct huft *)NULL;   /* just to keep compilers happy */ | ||
|  |   q = (struct huft *)NULL;      /* ditto */ | ||
|  |   z = 0;                        /* ditto */ | ||
|  | 
 | ||
|  |   /* go through the bit lengths (k already is bits in shortest code) */ | ||
|  |   for (; k <= g; k++) | ||
|  |   { | ||
|  |     a = c[k]; | ||
|  |     while (a--) | ||
|  |     { | ||
|  |       /* here i is the Huffman code of length k bits for value *p */ | ||
|  |       /* make tables up to required level */ | ||
|  |       while (k > w + l[h]) | ||
|  |       { | ||
|  |         w += l[h++];            /* add bits already decoded */ | ||
|  | 
 | ||
|  |         /* compute minimum size table less than or equal to *m bits */ | ||
|  |         z = (z = g - w) > (unsigned)*m ? *m : z;        /* upper limit */ | ||
|  |         if ((f = 1 << (j = k - w)) > a + 1)     /* try a k-w bit table */ | ||
|  |         {                       /* too few codes for k-w bit table */ | ||
|  |           f -= a + 1;           /* deduct codes from patterns left */ | ||
|  |           xp = c + k; | ||
|  |           while (++j < z)       /* try smaller tables up to z bits */ | ||
|  |           { | ||
|  |             if ((f <<= 1) <= *++xp) | ||
|  |               break;            /* enough codes to use up j bits */ | ||
|  |             f -= *xp;           /* else deduct codes from patterns */ | ||
|  |           } | ||
|  |         } | ||
|  |         if ((unsigned)w + j > el && (unsigned)w < el) | ||
|  |           j = el - w;           /* make EOB code end at table */ | ||
|  |         z = 1 << j;             /* table entries for j-bit table */ | ||
|  |         l[h] = j;               /* set table size in stack */ | ||
|  | 
 | ||
|  |         /* allocate and link in new table */ | ||
|  |         if ((q = (struct huft *) | ||
|  |                    ((*is->malloc_ptr)((z + 1)*sizeof(struct huft)))) == | ||
|  |                  (struct huft *)NULL) | ||
|  |         { | ||
|  |           if (h) | ||
|  |             huft_free(is, u[0]); | ||
|  |           return 3;             /* not enough memory */ | ||
|  |         } | ||
|  |         *t = q + 1;             /* link to list for huft_free() */ | ||
|  |         *(t = &(q->v.t)) = (struct huft *)NULL; | ||
|  |         u[h] = ++q;             /* table starts after link */ | ||
|  | 
 | ||
|  |         /* connect to last table, if there is one */ | ||
|  |         if (h) | ||
|  |         { | ||
|  |           x[h] = i;             /* save pattern for backing up */ | ||
|  |           r.b = (uch)l[h-1];    /* bits to dump before this table */ | ||
|  |           r.e = (uch)(16 + j);  /* bits in this table */ | ||
|  |           r.v.t = q;            /* pointer to this table */ | ||
|  |           j = (i & ((1 << w) - 1)) >> (w - l[h-1]); | ||
|  |           u[h-1][j] = r;        /* connect to last table */ | ||
|  |         } | ||
|  |       } | ||
|  | 
 | ||
|  |       /* set up table entry in r */ | ||
|  |       r.b = (uch)(k - w); | ||
|  |       if (p >= v + n) | ||
|  |         r.e = 99;               /* out of values--invalid code */ | ||
|  |       else if (*p < s) | ||
|  |       { | ||
|  |         r.e = (uch)(*p < 256 ? 16 : 15);    /* 256 is end-of-block code */ | ||
|  |         r.v.n = (ush) *p++;                 /* simple code is just the value */ | ||
|  |       } | ||
|  |       else | ||
|  |       { | ||
|  |         r.e = (uch)e[*p - s];   /* non-simple--look up in lists */ | ||
|  |         r.v.n = d[*p++ - s]; | ||
|  |       } | ||
|  | 
 | ||
|  |       /* fill code-like entries with r */ | ||
|  |       f = 1 << (k - w); | ||
|  |       for (j = i >> w; j < z; j += f) | ||
|  |         q[j] = r; | ||
|  | 
 | ||
|  |       /* backwards increment the k-bit code i */ | ||
|  |       for (j = 1 << (k - 1); i & j; j >>= 1) | ||
|  |         i ^= j; | ||
|  |       i ^= j; | ||
|  | 
 | ||
|  |       /* backup over finished tables */ | ||
|  |       while ((i & ((1 << w) - 1)) != x[h]) | ||
|  |         w -= l[--h];            /* don't need to update q */ | ||
|  |     } | ||
|  |   } | ||
|  | 
 | ||
|  |   /* return actual size of base table */ | ||
|  |   *m = l[0]; | ||
|  | 
 | ||
|  |   /* Return true (1) if we were given an incomplete table */ | ||
|  |   return y != 0 && g != 1; | ||
|  | } | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * inflate (decompress) the codes in a stored (uncompressed) block. | ||
|  |  * Return an error code or zero if it all goes ok. | ||
|  |  */ | ||
|  | 
 | ||
|  | static int inflate_stored( | ||
|  |   struct InflateState *is  /* Inflate state */ | ||
|  | ) | ||
|  | { | ||
|  |   ulg b;                /* bit buffer */ | ||
|  |   unsigned k;           /* number of bits in bit buffer */ | ||
|  |   unsigned w;           /* current window position */ | ||
|  | 
 | ||
|  |   /* make local copies of state */ | ||
|  |   b = is->bb;           /* initialize bit buffer */ | ||
|  |   k = is->bk;           /* initialize bit count */ | ||
|  |   w = is->wp;           /* initialize window position */ | ||
|  | 
 | ||
|  |   /*
 | ||
|  |    * Note that this code knows that NEEDBITS jumps to cleanup | ||
|  |    */ | ||
|  | 
 | ||
|  |   while (is->storelength > 0)  /* do until end of block */ | ||
|  |   { | ||
|  |     NEEDBITS(8) | ||
|  |     is->window[w++] = (uch) b; | ||
|  |     DUMPBITS(8) | ||
|  |     FLUSHWINDOW(w, FALSE); | ||
|  |     is->storelength--; | ||
|  |   } | ||
|  | 
 | ||
|  |   cleanup: | ||
|  | 
 | ||
|  |   /* restore the state from the locals */ | ||
|  |   is->bb = b;              /* restore bit buffer */ | ||
|  |   is->bk = k;              /* restore bit count */ | ||
|  |   is->wp = w;              /* restore window pointer */ | ||
|  | 
 | ||
|  |   if (is->storelength > 0) | ||
|  |     return -1; | ||
|  |   else | ||
|  |     return 0; | ||
|  | } | ||
|  | 
 | ||
|  | static int inflate_codes( | ||
|  |   struct InflateState *is, /* Inflate state */ | ||
|  |   struct huft *tl,         /* literal/length decoder table */ | ||
|  |   struct huft *td,         /* distance decoder table */ | ||
|  |   int bl,                  /* number of bits decoded by tl[] */ | ||
|  |   int bd                   /* number of bits decoded by td[] */ | ||
|  | ) | ||
|  | { | ||
|  |   unsigned e;           /* table entry flag/number of extra bits */ | ||
|  |   unsigned n, d;        /* length and index for copy */ | ||
|  |   unsigned w;           /* current window position */ | ||
|  |   struct huft *t;       /* pointer to table entry */ | ||
|  |   unsigned ml, md;      /* masks for bl and bd bits */ | ||
|  |   ulg b;                /* bit buffer */ | ||
|  |   unsigned k;           /* number of bits in bit buffer */ | ||
|  | 
 | ||
|  |   /* make local copies of state */ | ||
|  |   b = is->bb;           /* initialize bit buffer */ | ||
|  |   k = is->bk;           /* initialize bit count */ | ||
|  |   w = is->wp;           /* initialize window position */ | ||
|  | 
 | ||
|  |   /* inflate the coded data */ | ||
|  |   ml = mask_bits[bl];           /* precompute masks for speed */ | ||
|  |   md = mask_bits[bd]; | ||
|  |   for (;;)                      /* do until end of block */ | ||
|  |   { | ||
|  |     TRY | ||
|  |     { | ||
|  |       NEEDBITS((unsigned)bl) | ||
|  |       if ((e = (t = tl + ((unsigned)b & ml))->e) > 16) | ||
|  |         do { | ||
|  |           if (e == 99) | ||
|  |             return 1; | ||
|  |           DUMPBITS(t->b) | ||
|  |           e -= 16; | ||
|  |           NEEDBITS(e) | ||
|  |         } while ((e = (t = t->v.t + ((unsigned)b & mask_bits[e]))->e) > 16); | ||
|  |       DUMPBITS(t->b) | ||
|  | 
 | ||
|  |       if (e == 16)                /* it's a literal */ | ||
|  |       { | ||
|  |         is->window[w++] = (uch)t->v.n; | ||
|  |         FLUSHWINDOW(w, FALSE); | ||
|  |       } | ||
|  |       else if (e == 15)           /* it's an EOB */ | ||
|  |       { | ||
|  |         break; | ||
|  |       } | ||
|  |       else                        /* it's a length */ | ||
|  |       { | ||
|  |         /* get length of block to copy */ | ||
|  |         NEEDBITS(e) | ||
|  |         n = t->v.n + ((unsigned)b & mask_bits[e]); | ||
|  |         DUMPBITS(e); | ||
|  | 
 | ||
|  |         /* decode distance of block to copy */ | ||
|  |         NEEDBITS((unsigned)bd) | ||
|  |         if ((e = (t = td + ((unsigned)b & md))->e) > 16) | ||
|  |           do { | ||
|  |             if (e == 99) | ||
|  |               return 1; | ||
|  |             DUMPBITS(t->b) | ||
|  |             e -= 16; | ||
|  |             NEEDBITS(e) | ||
|  |           } while ((e = (t = t->v.t + ((unsigned)b & mask_bits[e]))->e) > 16); | ||
|  |         DUMPBITS(t->b) | ||
|  |         NEEDBITS(e) | ||
|  |         d = w - t->v.n - ((unsigned)b & mask_bits[e]); | ||
|  |         DUMPBITS(e) | ||
|  | 
 | ||
|  |         /* do the copy */ | ||
|  |         do { | ||
|  |           n -= (e = ((e = WINDOWSIZE - ((d &= WINDOWMASK) > w ? d : w)) > n) | ||
|  |                     ? n : e | ||
|  |                ); | ||
|  | #if defined(MEMCPY)
 | ||
|  |           if (w - d >= e)         /* (this test assumes unsigned comparison) */ | ||
|  |           { | ||
|  |             memcpy(is->window + w, is->window + d, e); | ||
|  |             w += e; | ||
|  |             d += e; | ||
|  |           } | ||
|  |           else                      /* do it slow to avoid memcpy() overlap */ | ||
|  | #endif /* MEMCPY */
 | ||
|  |             do { | ||
|  |               is->window[w++] = is->window[d++]; | ||
|  |             } while (--e); | ||
|  |           FLUSHWINDOW(w, FALSE); | ||
|  |         } while (n); | ||
|  |       } | ||
|  |     } | ||
|  |     CATCH_BEGIN | ||
|  |       is->wp = w;          /* restore window pointer */ | ||
|  |       return -1; | ||
|  |     CATCH_END | ||
|  |   } | ||
|  | 
 | ||
|  |   /* restore the state from the locals */ | ||
|  |   is->bb = b;              /* restore bit buffer */ | ||
|  |   is->bk = k;              /* restore bit count */ | ||
|  |   is->wp = w;              /* restore window pointer */ | ||
|  | 
 | ||
|  |   /* done */ | ||
|  |   return 0; | ||
|  | } | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * "decompress" an inflated type 0 (stored) block. | ||
|  |  */ | ||
|  | 
 | ||
|  | static int inflate_stored_setup( | ||
|  |   struct InflateState *is  /* Inflate state */ | ||
|  | ) | ||
|  | { | ||
|  |   unsigned n;           /* number of bytes in block */ | ||
|  |   ulg b;                /* bit buffer */ | ||
|  |   unsigned k;           /* number of bits in bit buffer */ | ||
|  | 
 | ||
|  |   /* make local copies of state */ | ||
|  |   b = is->bb;           /* initialize bit buffer */ | ||
|  |   k = is->bk;           /* initialize bit count */ | ||
|  | 
 | ||
|  |   TRY | ||
|  |   { | ||
|  |     /* go to byte boundary */ | ||
|  |     n = k & 7; | ||
|  |     DUMPBITS(n); | ||
|  | 
 | ||
|  |     /* get the length and its complement */ | ||
|  |     NEEDBITS(16) | ||
|  |     n = ((unsigned)b & 0xffff); | ||
|  |     DUMPBITS(16) | ||
|  |     NEEDBITS(16) | ||
|  |     if (n != (unsigned)((~b) & 0xffff)) | ||
|  |       return 1;                   /* error in compressed data */ | ||
|  |     DUMPBITS(16) | ||
|  |   } | ||
|  |   CATCH_BEGIN | ||
|  |     return -1; | ||
|  |   CATCH_END | ||
|  | 
 | ||
|  |   /* Save store state for this block */ | ||
|  |   is->storelength = n; | ||
|  | 
 | ||
|  |   /* restore the state from the locals */ | ||
|  |   is->bb = b;              /* restore bit buffer */ | ||
|  |   is->bk = k;              /* restore bit count */ | ||
|  |    | ||
|  |   return 0; | ||
|  | } | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * decompress an inflated type 1 (fixed Huffman codes) block.  We should | ||
|  |  * either replace this with a custom decoder, or at least precompute the | ||
|  |  * Huffman tables. | ||
|  |  */ | ||
|  | 
 | ||
|  | static int inflate_fixed_setup( | ||
|  |   struct InflateState *is  /* Inflate state */ | ||
|  | ) | ||
|  | { | ||
|  |   int i;                /* temporary variable */ | ||
|  |   struct huft *tl;      /* literal/length code table */ | ||
|  |   struct huft *td;      /* distance code table */ | ||
|  |   int bl;               /* lookup bits for tl */ | ||
|  |   int bd;               /* lookup bits for td */ | ||
|  |   unsigned l[288];      /* length list for huft_build */ | ||
|  | 
 | ||
|  |   /* set up literal table */ | ||
|  |   for (i = 0; i < 144; i++) | ||
|  |     l[i] = 8; | ||
|  |   for (; i < 256; i++) | ||
|  |     l[i] = 9; | ||
|  |   for (; i < 280; i++) | ||
|  |     l[i] = 7; | ||
|  |   for (; i < 288; i++)          /* make a complete, but wrong code set */ | ||
|  |     l[i] = 8; | ||
|  |   bl = 7; | ||
|  |   if ((i = huft_build(is, l, 288, 257, cplens, cplext, &tl, &bl)) != 0) | ||
|  |     return i; | ||
|  | 
 | ||
|  |   /* set up distance table */ | ||
|  |   for (i = 0; i < 30; i++)      /* make an incomplete code set */ | ||
|  |     l[i] = 5; | ||
|  |   bd = 5; | ||
|  |   if ((i = huft_build(is, l, 30, 0, cpdist, cpdext, &td, &bd)) > 1) | ||
|  |   { | ||
|  |     huft_free(is, tl); | ||
|  |     return i; | ||
|  |   } | ||
|  | 
 | ||
|  |   /* Save inflate state for this block */ | ||
|  |   is->tl = tl; | ||
|  |   is->td = td; | ||
|  |   is->bl = bl; | ||
|  |   is->bd = bd; | ||
|  | 
 | ||
|  |   return 0; | ||
|  | } | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * decompress an inflated type 2 (dynamic Huffman codes) block. | ||
|  |  */ | ||
|  | 
 | ||
|  | #define PKZIP_BUG_WORKAROUND
 | ||
|  | 
 | ||
|  | static int inflate_dynamic_setup( | ||
|  |   struct InflateState *is  /* Inflate state */ | ||
|  | ) | ||
|  | { | ||
|  |   int i;                /* temporary variables */ | ||
|  |   unsigned j; | ||
|  |   unsigned l;           /* last length */ | ||
|  |   unsigned m;           /* mask for bit lengths table */ | ||
|  |   unsigned n;           /* number of lengths to get */ | ||
|  |   struct huft *tl;      /* literal/length code table */ | ||
|  |   struct huft *td;      /* distance code table */ | ||
|  |   int bl;               /* lookup bits for tl */ | ||
|  |   int bd;               /* lookup bits for td */ | ||
|  |   unsigned nb;          /* number of bit length codes */ | ||
|  |   unsigned nl;          /* number of literal/length codes */ | ||
|  |   unsigned nd;          /* number of distance codes */ | ||
|  | #ifdef PKZIP_BUG_WORKAROUND
 | ||
|  |   unsigned ll[288+32];  /* literal/length and distance code lengths */ | ||
|  | #else
 | ||
|  |   unsigned ll[286+30];  /* literal/length and distance code lengths */ | ||
|  | #endif
 | ||
|  |   ulg b;                /* bit buffer */ | ||
|  |   unsigned k;           /* number of bits in bit buffer */ | ||
|  | 
 | ||
|  |   /* make local copies of state */ | ||
|  |   b = is->bb;           /* initialize bit buffer */ | ||
|  |   k = is->bk;           /* initialize bit count */ | ||
|  | 
 | ||
|  |   /* initialize tl for cleanup */ | ||
|  |   tl = NULL; | ||
|  | 
 | ||
|  |   TRY | ||
|  |   { | ||
|  |     /* read in table lengths */ | ||
|  |     NEEDBITS(5) | ||
|  |     nl = 257 + ((unsigned)b & 0x1f);      /* number of literal/length codes */ | ||
|  |     DUMPBITS(5) | ||
|  |     NEEDBITS(5) | ||
|  |     nd = 1 + ((unsigned)b & 0x1f);        /* number of distance codes */ | ||
|  |     DUMPBITS(5) | ||
|  |     NEEDBITS(4) | ||
|  |     nb = 4 + ((unsigned)b & 0xf);         /* number of bit length codes */ | ||
|  |     DUMPBITS(4) | ||
|  | #ifdef PKZIP_BUG_WORKAROUND
 | ||
|  |     if (nl > 288 || nd > 32) | ||
|  | #else
 | ||
|  |     if (nl > 286 || nd > 30) | ||
|  | #endif
 | ||
|  |       return 1;                   /* bad lengths */ | ||
|  | 
 | ||
|  |     /* read in bit-length-code lengths */ | ||
|  |     for (j = 0; j < 19; j++) ll[j] = 0; | ||
|  |     for (j = 0; j < nb; j++) | ||
|  |     { | ||
|  |       NEEDBITS(3) | ||
|  |       ll[border[j]] = (unsigned)b & 7; | ||
|  |       DUMPBITS(3) | ||
|  |     } | ||
|  | 
 | ||
|  |     /* build decoding table for trees--single level, 7 bit lookup */ | ||
|  |     bl = 7; | ||
|  |     if ((i = huft_build(is, ll, 19, 19, NULL, NULL, &tl, &bl)) != 0) | ||
|  |     { | ||
|  |       if (i == 1) | ||
|  |         huft_free(is, tl); | ||
|  |       return i;                   /* incomplete code set */ | ||
|  |     } | ||
|  | 
 | ||
|  |     /* read in literal and distance code lengths */ | ||
|  |     n = nl + nd; | ||
|  |     m = mask_bits[bl]; | ||
|  |     i = l = 0; | ||
|  |     while ((unsigned)i < n) | ||
|  |     { | ||
|  |       NEEDBITS((unsigned)bl) | ||
|  |       j = (td = tl + ((unsigned)b & m))->b; | ||
|  |       DUMPBITS(j) | ||
|  |       j = td->v.n; | ||
|  |       if (j < 16)                 /* length of code in bits (0..15) */ | ||
|  |         ll[i++] = l = j;          /* save last length in l */ | ||
|  |       else if (j == 16)           /* repeat last length 3 to 6 times */ | ||
|  |       { | ||
|  |         NEEDBITS(2) | ||
|  |         j = 3 + ((unsigned)b & 3); | ||
|  |         DUMPBITS(2) | ||
|  |         if ((unsigned)i + j > n) | ||
|  |           return 1; | ||
|  |         while (j--) | ||
|  |           ll[i++] = l; | ||
|  |       } | ||
|  |       else if (j == 17)           /* 3 to 10 zero length codes */ | ||
|  |       { | ||
|  |         NEEDBITS(3) | ||
|  |         j = 3 + ((unsigned)b & 7); | ||
|  |         DUMPBITS(3) | ||
|  |         if ((unsigned)i + j > n) | ||
|  |           return 1; | ||
|  |         while (j--) | ||
|  |           ll[i++] = 0; | ||
|  |         l = 0; | ||
|  |       } | ||
|  |       else                        /* j == 18: 11 to 138 zero length codes */ | ||
|  |       { | ||
|  |         NEEDBITS(7) | ||
|  |         j = 11 + ((unsigned)b & 0x7f); | ||
|  |         DUMPBITS(7) | ||
|  |         if ((unsigned)i + j > n) | ||
|  |           return 1; | ||
|  |         while (j--) | ||
|  |           ll[i++] = 0; | ||
|  |         l = 0; | ||
|  |       } | ||
|  |     } | ||
|  | 
 | ||
|  |     /* free decoding table for trees */ | ||
|  |     huft_free(is, tl); | ||
|  |   } | ||
|  |   CATCH_BEGIN | ||
|  |     if (tl) huft_free(is, tl); | ||
|  |     return -1; | ||
|  |   CATCH_END | ||
|  | 
 | ||
|  |   /* restore the state from the locals */ | ||
|  |   is->bb = b;              /* restore bit buffer */ | ||
|  |   is->bk = k;              /* restore bit count */ | ||
|  | 
 | ||
|  |   /* build the decoding tables for literal/length and distance codes */ | ||
|  |   bl = lbits; | ||
|  |   if ((i = huft_build(is, ll, nl, 257, cplens, cplext, &tl, &bl)) != 0) | ||
|  |   { | ||
|  |     if (i == 1) { | ||
|  |       /* incomplete literal tree */ | ||
|  |       huft_free(is, tl); | ||
|  |     } | ||
|  |     return i;                   /* incomplete code set */ | ||
|  |   } | ||
|  |   bd = dbits; | ||
|  |   if ((i = huft_build(is, ll + nl, nd, 0, cpdist, cpdext, &td, &bd)) != 0) | ||
|  |   { | ||
|  |     if (i == 1) { | ||
|  |       /* incomplete distance tree */ | ||
|  | #ifdef PKZIP_BUG_WORKAROUND
 | ||
|  |     } | ||
|  | #else
 | ||
|  |       huft_free(is, td); | ||
|  |     } | ||
|  |     huft_free(is, tl); | ||
|  |     return i;                   /* incomplete code set */ | ||
|  | #endif
 | ||
|  |   } | ||
|  | 
 | ||
|  |   /* Save inflate state for this block */ | ||
|  |   is->tl = tl; | ||
|  |   is->td = td; | ||
|  |   is->bl = bl; | ||
|  |   is->bd = bd; | ||
|  | 
 | ||
|  |   return 0; | ||
|  | } | ||
|  | 
 | ||
|  | /* Routine to initialize inflate decompression */ | ||
|  | void *InflateInitialize(                      /* returns InflateState       */ | ||
|  |   void *AppState,                             /* for passing to putbuffer   */ | ||
|  |   int (*putbuffer_ptr)(                       /* returns 0 on success       */ | ||
|  |     void *AppState,                           /* opaque ptr from Initialize */ | ||
|  |     unsigned char *buffer,                    /* buffer to put              */ | ||
|  |     long length                               /* length of buffer           */ | ||
|  |   ), | ||
|  |   void *(*malloc_ptr)(long length),           /* utility routine            */ | ||
|  |   void (*free_ptr)(void *buffer)              /* utility routine            */ | ||
|  | ) | ||
|  | { | ||
|  |   struct InflateState *is; | ||
|  | 
 | ||
|  |   /* Do some argument checking */ | ||
|  |   if ((!putbuffer_ptr) || (!malloc_ptr) || (!free_ptr)) return NULL; | ||
|  | 
 | ||
|  |   /* Allocate the InflateState memory area */ | ||
|  |   is = (struct InflateState *) (*malloc_ptr)(sizeof(struct InflateState)); | ||
|  |   if (!is) return NULL; | ||
|  | 
 | ||
|  |   /* Set up the initial values of the inflate state */ | ||
|  |   is->runtimetypeid1   = INFLATESTATETYPE; | ||
|  |   is->errorencountered = FALSE; | ||
|  | 
 | ||
|  |   is->bb               = 0; | ||
|  |   is->bk               = 0; | ||
|  |   is->bp               = 0; | ||
|  |   is->bs               = 0; | ||
|  | 
 | ||
|  |   is->wp               = 0; | ||
|  |   is->wf               = 0; | ||
|  | 
 | ||
|  |   is->state            = -1; | ||
|  |   is->lastblock        = FALSE; | ||
|  | 
 | ||
|  |   is->AppState         = AppState; | ||
|  | 
 | ||
|  |   is->putbuffer_ptr    = putbuffer_ptr; | ||
|  |   is->malloc_ptr       = malloc_ptr; | ||
|  |   is->free_ptr         = free_ptr; | ||
|  | 
 | ||
|  |   is->runtimetypeid2   = INFLATESTATETYPE; | ||
|  | 
 | ||
|  |   /* Return this state info to the caller */ | ||
|  |   return is; | ||
|  | } | ||
|  | 
 | ||
|  | /* Call-in routine to put a buffer into inflate decompression */ | ||
|  | int InflatePutBuffer(                         /* returns 0 on success       */ | ||
|  |   void *InflateState,                         /* opaque ptr from Initialize */ | ||
|  |   unsigned char *buffer,                      /* buffer to put              */ | ||
|  |   long length                                 /* length of buffer           */ | ||
|  | ) | ||
|  | { | ||
|  |   struct InflateState *is; | ||
|  | 
 | ||
|  |   int beginstate; | ||
|  | 
 | ||
|  |   /* Get (and check) the InflateState structure */ | ||
|  |   is = (struct InflateState *) InflateState; | ||
|  |   if (!is || (is->runtimetypeid1 != INFLATESTATETYPE) | ||
|  |           || (is->runtimetypeid2 != INFLATESTATETYPE)) return TRUE; | ||
|  |   if (is->errorencountered) return TRUE; | ||
|  | 
 | ||
|  |   do | ||
|  |   { | ||
|  |     int size, i; | ||
|  |      | ||
|  | 
 | ||
|  |     if ((is->state == -1) && (is->lastblock)) break; | ||
|  | 
 | ||
|  |     /* Save the beginning state */ | ||
|  |     beginstate = is->state; | ||
|  | 
 | ||
|  |     /* Push as much as possible into input buffer */ | ||
|  |     size = BUFFERSIZE - is->bs; | ||
|  |     if (size > length) size = (int) length; | ||
|  |     i = is->bp + is->bs; | ||
|  | 
 | ||
|  |     while (size-- > 0) | ||
|  |     { | ||
|  |       is->buffer[i++ & BUFFERMASK] = *buffer; | ||
|  |       is->bs++; | ||
|  |       buffer++; | ||
|  |       length--; | ||
|  |     } | ||
|  | 
 | ||
|  |     /* Process some more data */ | ||
|  |     if (is->state == -1) | ||
|  |     { | ||
|  |       int e;                /* last block flag */ | ||
|  |       unsigned t;           /* block type */ | ||
|  | 
 | ||
|  |       ulg b;                /* bit buffer */ | ||
|  |       unsigned k;           /* number of bits in bit buffer */ | ||
|  | 
 | ||
|  |       /* make local copies of state */ | ||
|  |       b = is->bb;           /* initialize bit buffer */ | ||
|  |       k = is->bk;           /* initialize bit count */ | ||
|  | 
 | ||
|  |       TRY | ||
|  |       { | ||
|  |         /* read in last block bit */ | ||
|  |         NEEDBITS(1) | ||
|  |         e = (int)b & 1; | ||
|  |         DUMPBITS(1) | ||
|  | 
 | ||
|  |         /* read in block type */ | ||
|  |         NEEDBITS(2) | ||
|  |         t = (unsigned)b & 3; | ||
|  |         DUMPBITS(2) | ||
|  | 
 | ||
|  |         if (t <= 2) | ||
|  |         { | ||
|  |           is->state     = t; | ||
|  |           is->lastblock = e; | ||
|  |         } | ||
|  |         else | ||
|  |         { | ||
|  |           ERROREXIT(is); | ||
|  |         } | ||
|  |       } | ||
|  |       CATCH_BEGIN | ||
|  |       CATCH_END | ||
|  |          | ||
|  |       /* restore the state from the locals */ | ||
|  |       is->bb = b;              /* restore bit buffer */ | ||
|  |       is->bk = k;              /* restore bit count */ | ||
|  |     } | ||
|  |     else if (is->state == 0) | ||
|  |     { | ||
|  |       int ret; | ||
|  | 
 | ||
|  |       ret = inflate_stored_setup(is); | ||
|  | 
 | ||
|  |       if (ret > 0) | ||
|  |         ERROREXIT(is); | ||
|  | 
 | ||
|  |       if (ret == 0) is->state += 10; | ||
|  |     } | ||
|  |     else if (is->state == 1) | ||
|  |     { | ||
|  |       int ret; | ||
|  | 
 | ||
|  |       ret = inflate_fixed_setup(is); | ||
|  | 
 | ||
|  |       if (ret > 0) | ||
|  |         ERROREXIT(is); | ||
|  | 
 | ||
|  |       if (ret == 0) is->state += 10; | ||
|  |     } | ||
|  |     else if (is->state == 2) | ||
|  |     { | ||
|  |       int ret; | ||
|  | 
 | ||
|  |       ret = inflate_dynamic_setup(is); | ||
|  |        | ||
|  |       if (ret > 0) | ||
|  |         ERROREXIT(is); | ||
|  | 
 | ||
|  |       if (ret == 0) is->state += 10; | ||
|  |     } | ||
|  |     else if (is->state == 10) | ||
|  |     { | ||
|  |       int ret; | ||
|  | 
 | ||
|  |       ret = inflate_stored(is); | ||
|  | 
 | ||
|  |       if (ret > 0) | ||
|  |         ERROREXIT(is); | ||
|  | 
 | ||
|  |       if (ret == 0) | ||
|  |       { | ||
|  |         is->state = -1; | ||
|  |       } | ||
|  |     } | ||
|  |     else if ((is->state == 11) || | ||
|  |              (is->state == 12)    ) | ||
|  |     { | ||
|  |       int ret; | ||
|  | 
 | ||
|  |       ret = inflate_codes(is, is->tl, is->td, is->bl, is->bd); | ||
|  | 
 | ||
|  |       if (ret > 0) | ||
|  |         ERROREXIT(is); | ||
|  | 
 | ||
|  |       if (ret == 0) | ||
|  |       { | ||
|  |         /* free the decoding tables */ | ||
|  |         huft_free(is, is->tl); | ||
|  |         huft_free(is, is->td); | ||
|  |         is->state = -1; | ||
|  |       } | ||
|  |     } | ||
|  |     else | ||
|  |     { | ||
|  |       ERROREXIT(is); | ||
|  |     } | ||
|  |   } | ||
|  |   while (length || (is->state != beginstate)); | ||
|  |    | ||
|  |   FLUSHWINDOW(is->wp, TRUE); | ||
|  | 
 | ||
|  |   return is->errorencountered; | ||
|  | } | ||
|  | 
 | ||
|  | /* Routine to terminate inflate decompression */ | ||
|  | int InflateTerminate(                         /* returns 0 on success       */ | ||
|  |   void *InflateState                          /* opaque ptr from Initialize */ | ||
|  | ) | ||
|  | { | ||
|  |   int err; | ||
|  |   void (*free_ptr)(void *buffer); | ||
|  | 
 | ||
|  |   struct InflateState *is; | ||
|  | 
 | ||
|  |   /* Get (and check) the InflateState structure */ | ||
|  |   is = (struct InflateState *) InflateState; | ||
|  |   if (!is || (is->runtimetypeid1 != INFLATESTATETYPE) | ||
|  |           || (is->runtimetypeid2 != INFLATESTATETYPE)) return TRUE; | ||
|  | 
 | ||
|  |   /* save the error return */ | ||
|  |   err = is->errorencountered || (is->bs > 0) | ||
|  |                              || (is->state != -1) | ||
|  |                              || (!is->lastblock); | ||
|  | 
 | ||
|  |   /* save the address of the free routine */ | ||
|  |   free_ptr = is->free_ptr; | ||
|  | 
 | ||
|  |   /* Deallocate everything */ | ||
|  |   (*free_ptr)(is); | ||
|  | 
 | ||
|  |   return err; | ||
|  | } |