Decompression code now appears to work.
This commit is contained in:
erich
parent
228a5751f2
commit
38e0cfc823
1 changed files with 596 additions and 61 deletions
|
|
@ -146,14 +146,31 @@ static unsigned long gzip_crc;
|
|||
/* internal extra variables for use of inflate code */
|
||||
static int block_type;
|
||||
static int block_len;
|
||||
static int last_block;
|
||||
static int code_state;
|
||||
|
||||
|
||||
/* Function prototypes */
|
||||
static void initialize_tables(void);
|
||||
static int huft_build(unsigned *, unsigned, unsigned, ush *, ush *,
|
||||
struct huft **, int *);
|
||||
static int huft_free(struct huft *);
|
||||
static int inflate_codes(struct huft *, struct huft *, int, int);
|
||||
|
||||
/*
|
||||
* Linear allocator.
|
||||
*/
|
||||
|
||||
static unsigned long linalloc_topaddr;
|
||||
|
||||
static void *
|
||||
linalloc(int size)
|
||||
{
|
||||
linalloc_topaddr = (linalloc_topaddr - size) & ~3;
|
||||
return (void *)linalloc_topaddr;
|
||||
}
|
||||
|
||||
static void
|
||||
reset_linalloc(void)
|
||||
{
|
||||
linalloc_topaddr = (mbi.mem_upper << 10) + 0x100000;
|
||||
}
|
||||
|
||||
|
||||
/* internal variable swap function */
|
||||
|
|
@ -303,9 +320,6 @@ gunzip_test_header(void)
|
|||
}
|
||||
|
||||
|
||||
uch slide[WSIZE];
|
||||
|
||||
|
||||
/* 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
|
||||
|
|
@ -332,9 +346,12 @@ struct huft {
|
|||
"uch *slide;" and then malloc'ed in the latter case. The definition
|
||||
must be in unzip.h, included above. */
|
||||
|
||||
|
||||
/* sliding window in uncompressed data */
|
||||
static uch slide[WSIZE];
|
||||
|
||||
/* current position in slide */
|
||||
unsigned wp;
|
||||
#define flush_output(w) (wp=(w),flush_window())
|
||||
static unsigned wp;
|
||||
|
||||
|
||||
/* Tables for deflate from PKZIP's appnote.txt. */
|
||||
|
|
@ -390,8 +407,8 @@ static ush cpdext[] = { /* Extra bits for distance codes */
|
|||
*/
|
||||
|
||||
|
||||
int lbits = 9; /* bits in base literal/length lookup table */
|
||||
int dbits = 6; /* bits in base distance lookup table */
|
||||
static int lbits = 9; /* bits in base literal/length lookup table */
|
||||
static int dbits = 6; /* bits in base distance lookup table */
|
||||
|
||||
|
||||
/* If BMAX needs to be larger than 16, then h and x[] should be ulg. */
|
||||
|
|
@ -399,12 +416,9 @@ int dbits = 6; /* bits in base distance lookup table */
|
|||
#define N_MAX 288 /* maximum number of codes in any set */
|
||||
|
||||
|
||||
unsigned hufts; /* track memory usage */
|
||||
static unsigned hufts; /* track memory usage */
|
||||
|
||||
|
||||
|
||||
/* XXXXXX */
|
||||
|
||||
/* Macros for inflate() bit peeking and grabbing.
|
||||
The usage is:
|
||||
|
||||
|
|
@ -435,35 +449,361 @@ unsigned hufts; /* track memory usage */
|
|||
the stream.
|
||||
*/
|
||||
|
||||
ulg bb; /* bit buffer */
|
||||
unsigned bk; /* bits in bit buffer */
|
||||
static ulg bb; /* bit buffer */
|
||||
static unsigned bk; /* bits in bit buffer */
|
||||
|
||||
ush mask_bits[] = {
|
||||
static ush mask_bits[] = {
|
||||
0x0000,
|
||||
0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
|
||||
0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
|
||||
};
|
||||
|
||||
#define NEEDBITS(n) {while(k<(n)){b|=((ulg)get_byte())<<k;k+=8;}}
|
||||
#define DUMPBITS(n) {b>>=(n);k-=(n);}
|
||||
#define NEEDBITS(n) do {while(k<(n)){b|=((ulg)get_byte())<<k;k+=8;}} while (0)
|
||||
#define DUMPBITS(n) do {b>>=(n);k-=(n);} while (0)
|
||||
|
||||
static void
|
||||
needbits(int n)
|
||||
#define INBUFSIZ 0x2000
|
||||
|
||||
static uch inbuf[INBUFSIZ];
|
||||
static int bufloc;
|
||||
|
||||
static int
|
||||
get_byte(void)
|
||||
{
|
||||
register k = bk;
|
||||
|
||||
while (k < n)
|
||||
if (filepos == gzip_data_offset || bufloc == INBUFSIZ)
|
||||
{
|
||||
bb |= ((ulg) get_byte()) << k;
|
||||
k += 8;
|
||||
bufloc = 0;
|
||||
read((int)inbuf, INBUFSIZ);
|
||||
}
|
||||
|
||||
bk = k;
|
||||
return inbuf[bufloc++];
|
||||
}
|
||||
|
||||
#define dumpbits(n) {bb>>=(n);bk-=(n);}
|
||||
/* decompression global pointers */
|
||||
static struct huft *tl; /* literal/length code table */
|
||||
static struct huft *td; /* distance code table */
|
||||
static int bl; /* lookup bits for tl */
|
||||
static int bd; /* lookup bits for td */
|
||||
|
||||
|
||||
/* more function prototypes */
|
||||
static int huft_build(unsigned *, unsigned, unsigned, ush *, ush *,
|
||||
struct huft **, int *);
|
||||
static int inflate_codes_in_window(void);
|
||||
|
||||
|
||||
/* 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. */
|
||||
|
||||
static int
|
||||
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) */
|
||||
ush *d, /* list of base values for non-simple codes */
|
||||
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 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 */
|
||||
struct huft *u[BMAX]; /* table stack */
|
||||
unsigned v[N_MAX]; /* values in order of bit length */
|
||||
register 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 */
|
||||
|
||||
/* Generate counts for each bit length */
|
||||
bzero((char *)c, sizeof(c));
|
||||
p = b; i = n;
|
||||
do {
|
||||
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;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* 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;
|
||||
|
||||
/* 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; /* bits decoded == (l * h) */
|
||||
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; /* 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 */
|
||||
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 */
|
||||
}
|
||||
}
|
||||
z = 1 << j; /* table entries for j-bit table */
|
||||
|
||||
/* allocate and link in new table */
|
||||
q = (struct huft *)linalloc((z + 1)*sizeof(struct huft));
|
||||
|
||||
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 */
|
||||
|
||||
/* 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 */
|
||||
}
|
||||
}
|
||||
|
||||
/* 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];
|
||||
}
|
||||
|
||||
/* fill code-like entries with r */
|
||||
f = 1 << (k - w);
|
||||
for (j = i >> w; j < z; j += f)
|
||||
q[j] = r;
|
||||
|
||||
/* backwards increment the k-bit code i */
|
||||
for (j = 1 << (k - 1); i & j; j >>= 1)
|
||||
i ^= j;
|
||||
i ^= j;
|
||||
|
||||
/* backup over finished tables */
|
||||
while ((i & ((1 << w) - 1)) != x[h])
|
||||
{
|
||||
h--; /* don't need to update q */
|
||||
w -= l;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/* Return true (1) if we were given an incomplete table */
|
||||
return y != 0 && g != 1;
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* inflate (decompress) the codes in a deflated (compressed) block.
|
||||
* Return an error code or zero if it all goes ok.
|
||||
*/
|
||||
|
||||
static unsigned inflate_n, inflate_d;
|
||||
|
||||
static int
|
||||
inflate_codes_in_window(void)
|
||||
{
|
||||
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 */
|
||||
d = inflate_d;
|
||||
n = inflate_n;
|
||||
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 */
|
||||
{
|
||||
if (!code_state)
|
||||
{
|
||||
NEEDBITS((unsigned)bl);
|
||||
if ((e = (t = tl + ((unsigned)b & ml))->e) > 16)
|
||||
do {
|
||||
if (e == 99)
|
||||
{
|
||||
errnum = ERR_BAD_GZIP_DATA;
|
||||
return 0;
|
||||
}
|
||||
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;
|
||||
if (w == WSIZE)
|
||||
break;
|
||||
}
|
||||
else /* it's an EOB or a length */
|
||||
{
|
||||
/* exit if end of block */
|
||||
if (e == 15)
|
||||
{
|
||||
block_len = 0;
|
||||
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)
|
||||
{
|
||||
errnum = ERR_BAD_GZIP_DATA;
|
||||
return 0;
|
||||
}
|
||||
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);
|
||||
code_state++;
|
||||
}
|
||||
}
|
||||
|
||||
if (code_state)
|
||||
{
|
||||
/* do the copy */
|
||||
do {
|
||||
n -= (e = (e = WSIZE - ((d &= WSIZE-1) > w ? d : w)) > n ? n : e);
|
||||
if (w - d >= e)
|
||||
{
|
||||
bcopy(slide + d, slide + w, e);
|
||||
w += e;
|
||||
d += e;
|
||||
}
|
||||
else /* purposefully use the overlap for extra copies here!! */
|
||||
{
|
||||
while (e--)
|
||||
slide[w++] = slide[d++];
|
||||
}
|
||||
if (w == WSIZE)
|
||||
break;
|
||||
} while (n);
|
||||
|
||||
if (!n)
|
||||
code_state--;
|
||||
|
||||
/* did we break from the loop too soon? */
|
||||
if (w == WSIZE)
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
/* restore the globals from the locals */
|
||||
inflate_d = d;
|
||||
inflate_n = n;
|
||||
wp = w; /* restore global window pointer */
|
||||
bb = b; /* restore global bit buffer */
|
||||
bk = k;
|
||||
|
||||
return !block_len;
|
||||
}
|
||||
|
||||
|
||||
/* get header for an inflated type 0 (stored) block. */
|
||||
|
||||
static void
|
||||
init_stored_block(void)
|
||||
{
|
||||
|
|
@ -474,8 +814,6 @@ init_stored_block(void)
|
|||
b = bb; /* initialize bit buffer */
|
||||
k = bk;
|
||||
|
||||
new_block = 0;
|
||||
|
||||
/* go to byte boundary */
|
||||
DUMPBITS(k & 7);
|
||||
|
||||
|
|
@ -494,6 +832,195 @@ init_stored_block(void)
|
|||
}
|
||||
|
||||
|
||||
/* get header for 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 void
|
||||
init_fixed_block()
|
||||
{
|
||||
int i; /* temporary variable */
|
||||
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(l, 288, 257, cplens, cplext, &tl, &bl)) != 0)
|
||||
{
|
||||
errnum = ERR_BAD_GZIP_DATA;
|
||||
return;
|
||||
}
|
||||
|
||||
/* 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)
|
||||
{
|
||||
errnum = ERR_BAD_GZIP_DATA;
|
||||
return;
|
||||
}
|
||||
|
||||
/* indicate we're now working on a block */
|
||||
code_state = 0;
|
||||
block_len++;
|
||||
}
|
||||
|
||||
|
||||
/* get header for an inflated type 2 (dynamic Huffman codes) block. */
|
||||
|
||||
static void
|
||||
init_dynamic_block(void)
|
||||
{
|
||||
int i; /* temporary variables */
|
||||
unsigned j;
|
||||
unsigned l; /* last length */
|
||||
unsigned m; /* mask for bit lengths table */
|
||||
unsigned n; /* number of lengths to get */
|
||||
unsigned nb; /* number of bit length codes */
|
||||
unsigned nl; /* number of literal/length codes */
|
||||
unsigned nd; /* number of distance codes */
|
||||
unsigned ll[286+30]; /* literal/length and distance code lengths */
|
||||
register ulg b; /* bit buffer */
|
||||
register unsigned k; /* number of bits in bit buffer */
|
||||
|
||||
/* 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);
|
||||
if (nl > 286 || nd > 30)
|
||||
{
|
||||
errnum = ERR_BAD_GZIP_DATA;
|
||||
return;
|
||||
}
|
||||
|
||||
/* 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;
|
||||
|
||||
/* build decoding table for trees--single level, 7 bit lookup */
|
||||
bl = 7;
|
||||
if ((i = huft_build(ll, 19, 19, NULL, NULL, &tl, &bl)) != 0)
|
||||
{
|
||||
errnum = ERR_BAD_GZIP_DATA;
|
||||
return;
|
||||
}
|
||||
|
||||
/* 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)
|
||||
{
|
||||
errnum = ERR_BAD_GZIP_DATA;
|
||||
return;
|
||||
}
|
||||
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)
|
||||
{
|
||||
errnum = ERR_BAD_GZIP_DATA;
|
||||
return;
|
||||
}
|
||||
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)
|
||||
{
|
||||
errnum = ERR_BAD_GZIP_DATA;
|
||||
return;
|
||||
}
|
||||
while (j--)
|
||||
ll[i++] = 0;
|
||||
l = 0;
|
||||
}
|
||||
}
|
||||
|
||||
/* free decoding table for trees */
|
||||
reset_linalloc();
|
||||
|
||||
/* restore the global bit buffer */
|
||||
bb = b;
|
||||
bk = k;
|
||||
|
||||
/* build the decoding tables for literal/length and distance codes */
|
||||
bl = lbits;
|
||||
if ((i = huft_build(ll, nl, 257, cplens, cplext, &tl, &bl)) != 0)
|
||||
{
|
||||
#if 0
|
||||
if (i == 1)
|
||||
printf("gunzip: incomplete literal tree\n");
|
||||
#endif
|
||||
|
||||
errnum = ERR_BAD_GZIP_DATA;
|
||||
return;
|
||||
}
|
||||
bd = dbits;
|
||||
if ((i = huft_build(ll + nl, nd, 0, cpdist, cpdext, &td, &bd)) != 0)
|
||||
{
|
||||
#if 0
|
||||
if (i == 1)
|
||||
printf("gunzip: incomplete distance tree\n");
|
||||
#endif
|
||||
|
||||
errnum = ERR_BAD_GZIP_DATA;
|
||||
return;
|
||||
}
|
||||
|
||||
/* indicate we're now working on a block */
|
||||
code_state = 0;
|
||||
block_len++;
|
||||
}
|
||||
|
||||
|
||||
static void
|
||||
get_new_block(void)
|
||||
{
|
||||
|
|
@ -519,6 +1046,13 @@ get_new_block(void)
|
|||
/* restore the global bit buffer */
|
||||
bb = b;
|
||||
bk = k;
|
||||
|
||||
if (block_type == INFLATE_STORED)
|
||||
init_stored_block();
|
||||
if (block_type == INFLATE_FIXED)
|
||||
init_fixed_block();
|
||||
if (block_type == INFLATE_DYNAMIC)
|
||||
init_dynamic_block();
|
||||
}
|
||||
|
||||
|
||||
|
|
@ -535,57 +1069,52 @@ inflate_window(void)
|
|||
while (wp < WSIZE && !errnum)
|
||||
{
|
||||
if (!block_len)
|
||||
get_new_block();
|
||||
|
||||
if (block_type > INFLATE_DYNAMIC)
|
||||
{
|
||||
errnum = ERR_BAD_GZIP_DATA;
|
||||
continue;
|
||||
if (last_block)
|
||||
break;
|
||||
|
||||
get_new_block();
|
||||
}
|
||||
|
||||
if (block_type > INFLATE_DYNAMIC)
|
||||
errnum = ERR_BAD_GZIP_DATA;
|
||||
|
||||
if (errnum)
|
||||
return;
|
||||
|
||||
/*
|
||||
* Expand stored block here.
|
||||
*/
|
||||
if (block_type == INFLATE_STORED)
|
||||
{
|
||||
int w = wp;
|
||||
|
||||
/*
|
||||
* This is basically a glorified pass-through
|
||||
*/
|
||||
|
||||
if (!block_len)
|
||||
init_stored_block();
|
||||
|
||||
while (block_len && wp < WSIZE && !errnum)
|
||||
while (block_len && w < WSIZE && !errnum)
|
||||
{
|
||||
slide[wp++] = get_byte();
|
||||
slide[w++] = get_byte();
|
||||
block_len--;
|
||||
}
|
||||
|
||||
wp = w;
|
||||
|
||||
continue;
|
||||
}
|
||||
|
||||
/*
|
||||
* Init other kind of block.
|
||||
*/
|
||||
|
||||
if (!block_len)
|
||||
{
|
||||
if (block_type == INFLATE_FIXED)
|
||||
init_fixed_block();
|
||||
if (block_type == INFLATE_DYNAMIC)
|
||||
init_dynamic_block();
|
||||
}
|
||||
|
||||
/*
|
||||
* Expand other kind of block.
|
||||
*/
|
||||
|
||||
if (inflate_codes() && !block_len)
|
||||
{
|
||||
/* we're done with the block, so free data structures */
|
||||
huft_free(tl);
|
||||
huft_free(td);
|
||||
}
|
||||
if (inflate_codes_in_window())
|
||||
reset_linalloc();
|
||||
}
|
||||
|
||||
saved_filepos += WSIZE;
|
||||
|
||||
/* XXX do CRC calculation here! */
|
||||
}
|
||||
|
||||
|
||||
|
|
@ -601,13 +1130,17 @@ initialize_tables(void)
|
|||
|
||||
/* reset partial decompression code */
|
||||
last_block = 0;
|
||||
block_len = 0;
|
||||
|
||||
/* reset memory allocation stuff */
|
||||
reset_linalloc();
|
||||
}
|
||||
|
||||
|
||||
int
|
||||
gunzip_read(int addr, int len)
|
||||
{
|
||||
int last_block, size; /* last block flag */
|
||||
int size; /* last block flag */
|
||||
int ret = 0;
|
||||
|
||||
compressed_file = 0;
|
||||
|
|
@ -629,15 +1162,17 @@ gunzip_read(int addr, int len)
|
|||
while (len > 0 && !errnum)
|
||||
{
|
||||
register int size;
|
||||
register char *srcaddr;
|
||||
|
||||
while (gzip_filepos >= saved_filepos)
|
||||
inflate_window();
|
||||
|
||||
srcaddr = (char *)((gzip_filepos & (WSIZE - 1)) + slide);
|
||||
size = saved_filepos - gzip_filepos;
|
||||
if (size > len)
|
||||
size = len;
|
||||
|
||||
bcopy((char *)slide, (char *)addr, size);
|
||||
bcopy(srcaddr, (char *)addr, size);
|
||||
|
||||
addr += size;
|
||||
len -= size;
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue