Signed-off-by: Joe Perches <[email protected]>
---
lib/inflate.c | 1265 ---------------------------------------------------------
1 files changed, 0 insertions(+), 1265 deletions(-)
delete mode 100644 lib/inflate.c
diff --git a/lib/inflate.c b/lib/inflate.c
deleted file mode 100644
index 845f91d..0000000
--- a/lib/inflate.c
+++ /dev/null
@@ -1,1265 +0,0 @@
-#define DEBG(x)
-#define DEBG1(x)
-/* inflate.c -- Not copyrighted 1992 by Mark Adler
- version c10p1, 10 January 1993 */
-
-/*
- * Adapted for booting Linux by Hannu Savolainen 1993
- * based on gzip-1.0.3
- *
- * Nicolas Pitre <[email protected]>, 1999/04/14 :
- * Little mods for all variable to reside either into rodata or bss segments
- * by marking constant variables with 'const' and initializing all the others
- * at run-time only. This allows for the kernel uncompressor to run
- * directly from Flash or ROM memory on embedded systems.
- */
-
-/*
- 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 32 K 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 deals with some chunk of data at a time, and
- decides which method to use on a chunk-by-chunk basis. A chunk might
- typically be 32 K or 64 K. If the chunk is incompressible, 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 codes 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.
-
- The Huffman codes themselves are decoded using a multi-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.
- */
-#include <linux/compiler.h>
-
-#ifdef RCSID
-static char rcsid[] = "#Id: inflate.c,v 0.14 1993/06/10 13:27:04 jloup Exp #";
-#endif
-
-#ifndef STATIC
-
-#if defined(STDC_HEADERS) || defined(HAVE_STDLIB_H)
-# include <sys/types.h>
-# include <stdlib.h>
-#endif
-
-#include "gzip.h"
-#define STATIC
-#endif /* !STATIC */
-
-#ifndef INIT
-#define INIT
-#endif
-
-#define slide window
-
-/* 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;
-};
-
-
-/* Function prototypes */
-STATIC int INIT huft_build OF((unsigned *, unsigned, unsigned,
- const ush *, const ush *, struct huft **, int *));
-STATIC int INIT huft_free OF((struct huft *));
-STATIC int INIT inflate_codes OF((struct huft *, struct huft *, int, int));
-STATIC int INIT inflate_stored OF((void));
-STATIC int INIT inflate_fixed OF((void));
-STATIC int INIT inflate_dynamic OF((void));
-STATIC int INIT inflate_block OF((int *));
-STATIC int INIT inflate OF((void));
-
-
-/* The inflate algorithm uses a sliding 32 K byte window on the uncompressed
- stream to find repeated byte strings. This is implemented here as a
- circular buffer. The index is updated simply by incrementing and then
- ANDing with 0x7fff (32K-1). */
-/* It is left to other modules to supply the 32 K area. It is assumed
- to be usable as if it were declared "uch slide[32768];" or as just
- "uch *slide;" and then malloc'ed in the latter case. The definition
- must be in unzip.h, included above. */
-/* unsigned wp; current position in slide */
-#define wp outcnt
-#define flush_output(w) (wp=(w),flush_window())
-
-/* 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};
-
-
-
-/* Macros for inflate() bit peeking and grabbing.
- The usage is:
-
- NEEDBITS(j)
- x = b & mask_bits[j];
- DUMPBITS(j)
-
- where 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.
-
- If we assume that EOB will be the longest code, then we will never
- ask for bits with NEEDBITS that are beyond the end of the stream.
- So, NEEDBITS should not read any more bytes than are needed to
- meet the request. Then no bytes need to be "returned" to the buffer
- at the end of the last block.
-
- However, this assumption is not true for fixed blocks--the EOB code
- is 7 bits, but the other literal/length codes can be 8 or 9 bits.
- (The EOB code is shorter than other codes because fixed blocks are
- generally short. So, while a block always has an EOB, many other
- literal/length codes have a significantly lower probability of
- showing up at all.) However, by making the first table have a
- lookup of seven bits, the EOB code will be found in that first
- lookup, and so will not require that too many bits be pulled from
- the stream.
- */
-
-STATIC ulg bb; /* bit buffer */
-STATIC unsigned bk; /* bits in bit buffer */
-
-STATIC const ush mask_bits[] = {
- 0x0000,
- 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
- 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
-};
-
-#define NEXTBYTE() ({ int v = get_byte(); if (v < 0) goto underrun; (uch)v; })
-#define NEEDBITS(n) {while(k<(n)){b|=((ulg)NEXTBYTE())<<k;k+=8;}}
-#define DUMPBITS(n) {b>>=(n);k-=(n);}
-
-
-/*
- 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 */
-
-
-STATIC unsigned hufts; /* track memory usage */
-
-
-STATIC int INIT huft_build(
- 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 */
- )
-/* 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. */
-{
- unsigned a; /* counter for codes of length k */
- unsigned f; /* i repeats in table every f entries */
- int g; /* maximum code length */
- int h; /* table level */
- register unsigned i; /* counter, current code */
- register unsigned j; /* counter */
- register int k; /* number of bits in current code */
- int l; /* bits per table (returned in m) */
- register unsigned *p; /* pointer into c[], b[], or v[] */
- register struct huft *q; /* points to current table */
- struct huft r; /* table entry for structure assignment */
- register int w; /* bits before this table == (l * h) */
- unsigned *xp; /* pointer into x */
- int y; /* number of dummy codes added */
- unsigned z; /* number of entries in current table */
- struct {
- unsigned c[BMAX+1]; /* bit length count table */
- struct huft *u[BMAX]; /* table stack */
- unsigned v[N_MAX]; /* values in order of bit length */
- unsigned x[BMAX+1]; /* bit offsets, then code stack */
- } *stk;
- unsigned *c, *v, *x;
- struct huft **u;
- int ret;
-
-DEBG("huft1 ");
-
- stk = malloc(sizeof(*stk));
- if (stk == NULL)
- return 3; /* out of memory */
-
- c = stk->c;
- v = stk->v;
- x = stk->x;
- u = stk->u;
-
- /* Generate counts for each bit length */
- memzero(stk->c, sizeof(stk->c));
- p = b; i = n;
- do {
- Tracecv(*p, (stderr, (n-i >= ' ' && n-i <= '~' ? "%c %d\n" : "0x%x %d\n"),
- n-i, *p));
- c[*p]++; /* assume all entries <= BMAX */
- p++; /* Can't combine with above line (Solaris bug) */
- } while (--i);
- if (c[0] == n) /* null input--all zero length codes */
- {
- *t = (struct huft *)NULL;
- *m = 0;
- ret = 2;
- goto out;
- }
-
-DEBG("huft2 ");
-
- /* Find minimum and maximum length, bound *m by those */
- l = *m;
- for (j = 1; j <= BMAX; j++)
- if (c[j])
- break;
- k = j; /* minimum code length */
- if ((unsigned)l < j)
- l = j;
- for (i = BMAX; i; i--)
- if (c[i])
- break;
- g = i; /* maximum code length */
- if ((unsigned)l > i)
- l = i;
- *m = l;
-
-DEBG("huft3 ");
-
- /* Adjust last length count to fill out codes, if needed */
- for (y = 1 << j; j < i; j++, y <<= 1)
- if ((y -= c[j]) < 0) {
- ret = 2; /* bad input: more codes than bits */
- goto out;
- }
- if ((y -= c[i]) < 0) {
- ret = 2;
- goto out;
- }
- c[i] += y;
-
-DEBG("huft4 ");
-
- /* 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++);
- }
-
-DEBG("huft5 ");
-
- /* 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);
- n = x[g]; /* set n to length of v */
-
-DEBG("h6 ");
-
- /* Generate the Huffman codes and for each, make the table entries */
- x[0] = i = 0; /* first Huffman code is zero */
- p = v; /* grab values in bit order */
- h = -1; /* no tables yet--level -1 */
- w = -l; /* bits decoded == (l * h) */
- u[0] = (struct huft *)NULL; /* just to keep compilers happy */
- q = (struct huft *)NULL; /* ditto */
- z = 0; /* ditto */
-DEBG("h6a ");
-
- /* go through the bit lengths (k already is bits in shortest code) */
- for (; k <= g; k++)
- {
-DEBG("h6b ");
- a = c[k];
- while (a--)
- {
-DEBG("h6b1 ");
- /* here i is the Huffman code of length k bits for value *p */
- /* make tables up to required level */
- while (k > w + l)
- {
-DEBG1("1 ");
- h++;
- w += l; /* previous table always l bits */
-
- /* compute minimum size table less than or equal to l bits */
- z = (z = g - w) > (unsigned)l ? l : z; /* upper limit on table size */
- if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
- { /* too few codes for k-w bit table */
-DEBG1("2 ");
- f -= a + 1; /* deduct codes from patterns left */
- xp = c + k;
- if (j < z)
- while (++j < z) /* try smaller tables up to z bits */
- {
- if ((f <<= 1) <= *++xp)
- break; /* enough codes to use up j bits */
- f -= *xp; /* else deduct codes from patterns */
- }
- }
-DEBG1("3 ");
- z = 1 << j; /* table entries for j-bit table */
-
- /* allocate and link in new table */
- if ((q = (struct huft *)malloc((z + 1)*sizeof(struct huft))) ==
- (struct huft *)NULL)
- {
- if (h)
- huft_free(u[0]);
- ret = 3; /* not enough memory */
- goto out;
- }
-DEBG1("4 ");
- hufts += z + 1; /* track memory usage */
- *t = q + 1; /* link to list for huft_free() */
- *(t = &(q->v.t)) = (struct huft *)NULL;
- u[h] = ++q; /* table starts after link */
-
-DEBG1("5 ");
- /* connect to last table, if there is one */
- if (h)
- {
- x[h] = i; /* save pattern for backing up */
- r.b = (uch)l; /* 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 >> (w - l); /* (get around Turbo C bug) */
- u[h-1][j] = r; /* connect to last table */
- }
-DEBG1("6 ");
- }
-DEBG("h6c ");
-
- /* 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 */
- p++; /* one compiler does not like *p++ */
- }
- else
- {
- r.e = (uch)e[*p - s]; /* non-simple--look up in lists */
- r.v.n = d[*p++ - s];
- }
-DEBG("h6d ");
-
- /* fill code-like entries with r */
- f = 1 << (k - w);
- for (j = i >> w; j < z; j += f)
- q[j] = r;
-
- /* backwards increment the k-bit code i */
- for (j = 1 << (k - 1); i & j; j >>= 1)
- i ^= j;
- i ^= j;
-
- /* backup over finished tables */
- while ((i & ((1 << w) - 1)) != x[h])
- {
- h--; /* don't need to update q */
- w -= l;
- }
-DEBG("h6e ");
- }
-DEBG("h6f ");
- }
-
-DEBG("huft7 ");
-
- /* Return true (1) if we were given an incomplete table */
- ret = y != 0 && g != 1;
-
- out:
- free(stk);
- return ret;
-}
-
-
-
-STATIC int INIT huft_free(
- struct huft *t /* table to free */
- )
-/* Free the malloc'ed tables built by huft_build(), which makes a linked
- list of the tables it made, with the links in a dummy first entry of
- each table. */
-{
- register 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;
- free((char*)p);
- p = q;
- }
- return 0;
-}
-
-
-STATIC int INIT inflate_codes(
- struct huft *tl, /* literal/length decoder tables */
- struct huft *td, /* distance decoder tables */
- int bl, /* number of bits decoded by tl[] */
- int bd /* number of bits decoded by td[] */
- )
-/* inflate (decompress) the codes in a deflated (compressed) block.
- Return an error code or zero if it all goes ok. */
-{
- register 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 */
- register ulg b; /* bit buffer */
- register unsigned k; /* number of bits in bit buffer */
-
-
- /* make local copies of globals */
- b = bb; /* initialize bit buffer */
- k = bk;
- w = 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 */
- {
- 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) /* then it's a literal */
- {
- slide[w++] = (uch)t->v.n;
- Tracevv((stderr, "%c", slide[w-1]));
- if (w == WSIZE)
- {
- flush_output(w);
- w = 0;
- }
- }
- else /* it's an EOB or a length */
- {
- /* exit if end of block */
- if (e == 15)
- break;
-
- /* 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)
- Tracevv((stderr,"\\[%d,%d]", w-d, n));
-
- /* do the copy */
- do {
- n -= (e = (e = WSIZE - ((d &= WSIZE-1) > w ? d : w)) > n ? n : e);
-#if !defined(NOMEMCPY) && !defined(DEBUG)
- if (w - d >= e) /* (this test assumes unsigned comparison) */
- {
- memcpy(slide + w, slide + d, e);
- w += e;
- d += e;
- }
- else /* do it slow to avoid memcpy() overlap */
-#endif /* !NOMEMCPY */
- do {
- slide[w++] = slide[d++];
- Tracevv((stderr, "%c", slide[w-1]));
- } while (--e);
- if (w == WSIZE)
- {
- flush_output(w);
- w = 0;
- }
- } while (n);
- }
- }
-
-
- /* restore the globals from the locals */
- wp = w; /* restore global window pointer */
- bb = b; /* restore global bit buffer */
- bk = k;
-
- /* done */
- return 0;
-
- underrun:
- return 4; /* Input underrun */
-}
-
-
-
-STATIC int INIT inflate_stored(void)
-/* "decompress" an inflated type 0 (stored) block. */
-{
- unsigned n; /* number of bytes in block */
- unsigned w; /* current window position */
- register ulg b; /* bit buffer */
- register unsigned k; /* number of bits in bit buffer */
-
-DEBG("<stor");
-
- /* make local copies of globals */
- b = bb; /* initialize bit buffer */
- k = bk;
- w = wp; /* initialize window position */
-
-
- /* 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)
-
-
- /* read and output the compressed data */
- while (n--)
- {
- NEEDBITS(8)
- slide[w++] = (uch)b;
- if (w == WSIZE)
- {
- flush_output(w);
- w = 0;
- }
- DUMPBITS(8)
- }
-
-
- /* restore the globals from the locals */
- wp = w; /* restore global window pointer */
- bb = b; /* restore global bit buffer */
- bk = k;
-
- DEBG(">");
- return 0;
-
- underrun:
- return 4; /* Input underrun */
-}
-
-
-/*
- * We use `noinline' here to prevent gcc-3.5 from using too much stack space
- */
-STATIC int noinline INIT inflate_fixed(void)
-/* 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. */
-{
- 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; /* length list for huft_build */
-
-DEBG("<fix");
-
- l = malloc(sizeof(*l) * 288);
- if (l == NULL)
- return 3; /* out of memory */
-
- /* 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(l, 288, 257, cplens, cplext, &tl, &bl)) != 0) {
- free(l);
- 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(l, 30, 0, cpdist, cpdext, &td, &bd)) > 1)
- {
- huft_free(tl);
- free(l);
-
- DEBG(">");
- return i;
- }
-
-
- /* decompress until an end-of-block code */
- if (inflate_codes(tl, td, bl, bd)) {
- free(l);
- return 1;
- }
-
- /* free the decoding tables, return */
- free(l);
- huft_free(tl);
- huft_free(td);
- return 0;
-}
-
-
-/*
- * We use `noinline' here to prevent gcc-3.5 from using too much stack space
- */
-STATIC int noinline INIT inflate_dynamic(void)
-/* decompress an inflated type 2 (dynamic Huffman codes) block. */
-{
- 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 */
- unsigned *ll; /* literal/length and distance code lengths */
- register ulg b; /* bit buffer */
- register unsigned k; /* number of bits in bit buffer */
- int ret;
-
-DEBG("<dyn");
-
-#ifdef PKZIP_BUG_WORKAROUND
- ll = malloc(sizeof(*ll) * (288+32)); /* literal/length and distance code lengths */
-#else
- ll = malloc(sizeof(*ll) * (286+30)); /* literal/length and distance code lengths */
-#endif
-
- /* make local bit buffer */
- b = bb;
- k = bk;
-
-
- /* 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
- {
- ret = 1; /* bad lengths */
- goto out;
- }
-
-DEBG("dyn1 ");
-
- /* read in bit-length-code lengths */
- for (j = 0; j < nb; j++)
- {
- NEEDBITS(3)
- ll[border[j]] = (unsigned)b & 7;
- DUMPBITS(3)
- }
- for (; j < 19; j++)
- ll[border[j]] = 0;
-
-DEBG("dyn2 ");
-
- /* build decoding table for trees--single level, 7 bit lookup */
- bl = 7;
- if ((i = huft_build(ll, 19, 19, NULL, NULL, &tl, &bl)) != 0)
- {
- if (i == 1)
- huft_free(tl);
- ret = i; /* incomplete code set */
- goto out;
- }
-
-DEBG("dyn3 ");
-
- /* 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) {
- ret = 1;
- goto out;
- }
- 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) {
- ret = 1;
- goto out;
- }
- 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) {
- ret = 1;
- goto out;
- }
- while (j--)
- ll[i++] = 0;
- l = 0;
- }
- }
-
-DEBG("dyn4 ");
-
- /* free decoding table for trees */
- huft_free(tl);
-
-DEBG("dyn5 ");
-
- /* restore the global bit buffer */
- bb = b;
- bk = k;
-
-DEBG("dyn5a ");
-
- /* build the decoding tables for literal/length and distance codes */
- bl = lbits;
- if ((i = huft_build(ll, nl, 257, cplens, cplext, &tl, &bl)) != 0)
- {
-DEBG("dyn5b ");
- if (i == 1) {
- error("incomplete literal tree");
- huft_free(tl);
- }
- ret = i; /* incomplete code set */
- goto out;
- }
-DEBG("dyn5c ");
- bd = dbits;
- if ((i = huft_build(ll + nl, nd, 0, cpdist, cpdext, &td, &bd)) != 0)
- {
-DEBG("dyn5d ");
- if (i == 1) {
- error("incomplete distance tree");
-#ifdef PKZIP_BUG_WORKAROUND
- i = 0;
- }
-#else
- huft_free(td);
- }
- huft_free(tl);
- ret = i; /* incomplete code set */
- goto out;
-#endif
- }
-
-DEBG("dyn6 ");
-
- /* decompress until an end-of-block code */
- if (inflate_codes(tl, td, bl, bd)) {
- ret = 1;
- goto out;
- }
-
-DEBG("dyn7 ");
-
- /* free the decoding tables, return */
- huft_free(tl);
- huft_free(td);
-
- DEBG(">");
- ret = 0;
-out:
- free(ll);
- return ret;
-
-underrun:
- ret = 4; /* Input underrun */
- goto out;
-}
-
-
-
-STATIC int INIT inflate_block(
- int *e /* last block flag */
- )
-/* decompress an inflated block */
-{
- unsigned t; /* block type */
- register ulg b; /* bit buffer */
- register unsigned k; /* number of bits in bit buffer */
-
- DEBG("<blk");
-
- /* make local bit buffer */
- b = bb;
- k = bk;
-
-
- /* 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)
-
-
- /* restore the global bit buffer */
- bb = b;
- bk = k;
-
- /* inflate that block type */
- if (t == 2)
- return inflate_dynamic();
- if (t == 0)
- return inflate_stored();
- if (t == 1)
- return inflate_fixed();
-
- DEBG(">");
-
- /* bad block type */
- return 2;
-
- underrun:
- return 4; /* Input underrun */
-}
-
-
-
-STATIC int INIT inflate(void)
-/* decompress an inflated entry */
-{
- int e; /* last block flag */
- int r; /* result code */
- unsigned h; /* maximum struct huft's malloc'ed */
- void *ptr;
-
- /* initialize window, bit buffer */
- wp = 0;
- bk = 0;
- bb = 0;
-
-
- /* decompress until the last block */
- h = 0;
- do {
- hufts = 0;
- gzip_mark(&ptr);
- if ((r = inflate_block(&e)) != 0) {
- gzip_release(&ptr);
- return r;
- }
- gzip_release(&ptr);
- if (hufts > h)
- h = hufts;
- } while (!e);
-
- /* Undo too much lookahead. The next read will be byte aligned so we
- * can discard unused bits in the last meaningful byte.
- */
- while (bk >= 8) {
- bk -= 8;
- inptr--;
- }
-
- /* flush out slide */
- flush_output(wp);
-
-
- /* return success */
-#ifdef DEBUG
- fprintf(stderr, "<%u> ", h);
-#endif /* DEBUG */
- return 0;
-}
-
-/**********************************************************************
- *
- * The following are support routines for inflate.c
- *
- **********************************************************************/
-
-static ulg crc_32_tab[256];
-static ulg crc; /* initialized in makecrc() so it'll reside in bss */
-#define CRC_VALUE (crc ^ 0xffffffffUL)
-
-/*
- * Code to compute the CRC-32 table. Borrowed from
- * gzip-1.0.3/makecrc.c.
- */
-
-static void INIT
-makecrc(void)
-{
-/* Not copyrighted 1990 Mark Adler */
-
- unsigned long c; /* crc shift register */
- unsigned long e; /* polynomial exclusive-or pattern */
- int i; /* counter for all possible eight bit values */
- int k; /* byte being shifted into crc apparatus */
-
- /* terms of polynomial defining this crc (except x^32): */
- static const int p[] = {0,1,2,4,5,7,8,10,11,12,16,22,23,26};
-
- /* Make exclusive-or pattern from polynomial */
- e = 0;
- for (i = 0; i < sizeof(p)/sizeof(int); i++)
- e |= 1L << (31 - p[i]);
-
- crc_32_tab[0] = 0;
-
- for (i = 1; i < 256; i++)
- {
- c = 0;
- for (k = i | 256; k != 1; k >>= 1)
- {
- c = c & 1 ? (c >> 1) ^ e : c >> 1;
- if (k & 1)
- c ^= e;
- }
- crc_32_tab[i] = c;
- }
-
- /* this is initialized here so this code could reside in ROM */
- crc = (ulg)0xffffffffUL; /* shift register contents */
-}
-
-/* gzip flag byte */
-#define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */
-#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
-#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
-#define ORIG_NAME 0x08 /* bit 3 set: original file name present */
-#define COMMENT 0x10 /* bit 4 set: file comment present */
-#define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */
-#define RESERVED 0xC0 /* bit 6,7: reserved */
-
-/*
- * Do the uncompression!
- */
-static int INIT gunzip(void)
-{
- uch flags;
- unsigned char magic[2]; /* magic header */
- char method;
- ulg orig_crc = 0; /* original crc */
- ulg orig_len = 0; /* original uncompressed length */
- int res;
-
- magic[0] = NEXTBYTE();
- magic[1] = NEXTBYTE();
- method = NEXTBYTE();
-
- if (magic[0] != 037 ||
- ((magic[1] != 0213) && (magic[1] != 0236))) {
- error("bad gzip magic numbers");
- return -1;
- }
-
- /* We only support method #8, DEFLATED */
- if (method != 8) {
- error("internal error, invalid method");
- return -1;
- }
-
- flags = (uch)get_byte();
- if ((flags & ENCRYPTED) != 0) {
- error("Input is encrypted");
- return -1;
- }
- if ((flags & CONTINUATION) != 0) {
- error("Multi part input");
- return -1;
- }
- if ((flags & RESERVED) != 0) {
- error("Input has invalid flags");
- return -1;
- }
- NEXTBYTE(); /* Get timestamp */
- NEXTBYTE();
- NEXTBYTE();
- NEXTBYTE();
-
- (void)NEXTBYTE(); /* Ignore extra flags for the moment */
- (void)NEXTBYTE(); /* Ignore OS type for the moment */
-
- if ((flags & EXTRA_FIELD) != 0) {
- unsigned len = (unsigned)NEXTBYTE();
- len |= ((unsigned)NEXTBYTE())<<8;
- while (len--) (void)NEXTBYTE();
- }
-
- /* Get original file name if it was truncated */
- if ((flags & ORIG_NAME) != 0) {
- /* Discard the old name */
- while (NEXTBYTE() != 0) /* null */ ;
- }
-
- /* Discard file comment if any */
- if ((flags & COMMENT) != 0) {
- while (NEXTBYTE() != 0) /* null */ ;
- }
-
- /* Decompress */
- if ((res = inflate())) {
- switch (res) {
- case 0:
- break;
- case 1:
- error("invalid compressed format (err=1)");
- break;
- case 2:
- error("invalid compressed format (err=2)");
- break;
- case 3:
- error("out of memory");
- break;
- case 4:
- error("out of input data");
- break;
- default:
- error("invalid compressed format (other)");
- }
- return -1;
- }
-
- /* Get the crc and original length */
- /* crc32 (see algorithm.doc)
- * uncompressed input size modulo 2^32
- */
- orig_crc = (ulg) NEXTBYTE();
- orig_crc |= (ulg) NEXTBYTE() << 8;
- orig_crc |= (ulg) NEXTBYTE() << 16;
- orig_crc |= (ulg) NEXTBYTE() << 24;
-
- orig_len = (ulg) NEXTBYTE();
- orig_len |= (ulg) NEXTBYTE() << 8;
- orig_len |= (ulg) NEXTBYTE() << 16;
- orig_len |= (ulg) NEXTBYTE() << 24;
-
- /* Validate decompression */
- if (orig_crc != CRC_VALUE) {
- error("crc error");
- return -1;
- }
- if (orig_len != bytes_out) {
- error("length error");
- return -1;
- }
- return 0;
-
- underrun: /* NEXTBYTE() goto's here if needed */
- error("out of input data");
- return -1;
-}
-
-
--
1.5.3.7.949.g2221a6
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