📄 app_zlib.c
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}
inflate_blocks_statef *inflate_blocks_new(z_streamp z, check_func c, uInt w)
{
inflate_blocks_statef *s;
if ((s = (inflate_blocks_statef *)ZALLOC
(z,1,sizeof(struct inflate_blocks_state))) == Z_NULL)
return s;
if ((s->hufts =
(inflate_huft *)ZALLOC(z, sizeof(inflate_huft), MANY)) == Z_NULL)
{
ZFREE(z, s);
return Z_NULL;
}
if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL)
{
ZFREE(z, s->hufts);
ZFREE(z, s);
return Z_NULL;
}
s->end = s->window + w;
s->checkfn = c;
s->mode = TYPE;
Tracev((stderr, "inflate: blocks allocated\n"));
inflate_blocks_reset(s, z, Z_NULL);
return s;
}
int inflate_blocks(inflate_blocks_statef *s, z_streamp z, int r)
{
uInt t; /* temporary storage */
uLong b; /* bit buffer */
uInt k; /* bits in bit buffer */
Bytef *p; /* input data pointer */
uInt n; /* bytes available there */
Bytef *q; /* output window write pointer */
uInt m; /* bytes to end of window or read pointer */
/* copy input/output information to locals (UPDATE macro restores) */
LOAD
/* process input based on current state */
while (1) switch (s->mode)
{
case TYPE:
NEEDBITS(3)
t = (uInt)b & 7;
s->last = t & 1;
switch (t >> 1)
{
case 0: /* stored */
Tracev((stderr, "inflate: stored block%s\n",
s->last ? " (last)" : ""));
DUMPBITS(3)
t = k & 7; /* go to byte boundary */
DUMPBITS(t)
s->mode = LENS; /* get length of stored block */
break;
case 1: /* fixed */
Tracev((stderr, "inflate: fixed codes block%s\n",
s->last ? " (last)" : ""));
{
uInt bl, bd;
inflate_huft *tl, *td;
inflate_trees_fixed(&bl, &bd, &tl, &td, z);
s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z);
if (s->sub.decode.codes == Z_NULL)
{
r = Z_MEM_ERROR;
LEAVE
}
}
DUMPBITS(3)
s->mode = CODES;
break;
case 2: /* dynamic */
Tracev((stderr, "inflate: dynamic codes block%s\n",
s->last ? " (last)" : ""));
DUMPBITS(3)
s->mode = TABLE;
break;
case 3: /* illegal */
DUMPBITS(3)
s->mode = BAD;
z->msg = (char*)"invalid block type";
r = Z_DATA_ERROR;
LEAVE
}
break;
case LENS:
NEEDBITS(32)
if ((((~b) >> 16) & 0xffff) != (b & 0xffff))
{
s->mode = BAD;
z->msg = (char*)"invalid stored block lengths";
r = Z_DATA_ERROR;
LEAVE
}
s->sub.left = (uInt)b & 0xffff;
b = k = 0; /* dump bits */
Tracev((stderr, "inflate: stored length %u\n", s->sub.left));
s->mode = s->sub.left ? STORED : (s->last ? DRY : TYPE);
break;
case STORED:
if (n == 0)
LEAVE
NEEDOUT
t = s->sub.left;
if (t > n) t = n;
if (t > m) t = m;
zmemcpy(q, p, t);
p += t; n -= t;
q += t; m -= t;
if ((s->sub.left -= t) != 0)
break;
Tracev((stderr, "inflate: stored end, %lu total out\n",
z->total_out + (q >= s->read ? q - s->read :
(s->end - s->read) + (q - s->window))));
s->mode = s->last ? DRY : TYPE;
break;
case TABLE:
NEEDBITS(14)
s->sub.trees.table = t = (uInt)b & 0x3fff;
#ifndef PKZIP_BUG_WORKAROUND
if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
{
s->mode = BAD;
z->msg = (char*)"too many length or distance symbols";
r = Z_DATA_ERROR;
LEAVE
}
#endif
t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
{
r = Z_MEM_ERROR;
LEAVE
}
DUMPBITS(14)
s->sub.trees.index = 0;
Tracev((stderr, "inflate: table sizes ok\n"));
s->mode = BTREE;
case BTREE:
while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10))
{
NEEDBITS(3)
s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7;
DUMPBITS(3)
}
while (s->sub.trees.index < 19)
s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
s->sub.trees.bb = 7;
t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
&s->sub.trees.tb, s->hufts, z);
if (t != Z_OK)
{
ZFREE(z, s->sub.trees.blens);
r = t;
if (r == Z_DATA_ERROR)
s->mode = BAD;
LEAVE
}
s->sub.trees.index = 0;
Tracev((stderr, "inflate: bits tree ok\n"));
s->mode = DTREE;
case DTREE:
while (t = s->sub.trees.table,
s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
{
inflate_huft *h;
uInt i, j, c;
t = s->sub.trees.bb;
NEEDBITS(t)
h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]);
t = h->bits;
c = h->base;
if (c < 16)
{
DUMPBITS(t)
s->sub.trees.blens[s->sub.trees.index++] = c;
}
else /* c == 16..18 */
{
i = c == 18 ? 7 : c - 14;
j = c == 18 ? 11 : 3;
NEEDBITS(t + i)
DUMPBITS(t)
j += (uInt)b & inflate_mask[i];
DUMPBITS(i)
i = s->sub.trees.index;
t = s->sub.trees.table;
if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) ||
(c == 16 && i < 1))
{
ZFREE(z, s->sub.trees.blens);
s->mode = BAD;
z->msg = (char*)"invalid bit length repeat";
r = Z_DATA_ERROR;
LEAVE
}
c = c == 16 ? s->sub.trees.blens[i - 1] : 0;
do {
s->sub.trees.blens[i++] = c;
} while (--j);
s->sub.trees.index = i;
}
}
s->sub.trees.tb = Z_NULL;
{
uInt bl, bd;
inflate_huft *tl, *td;
inflate_codes_statef *c;
bl = 9; /* must be <= 9 for lookahead assumptions */
bd = 6; /* must be <= 9 for lookahead assumptions */
t = s->sub.trees.table;
t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
s->sub.trees.blens, &bl, &bd, &tl, &td,
s->hufts, z);
ZFREE(z, s->sub.trees.blens);
if (t != Z_OK)
{
if (t == (uInt)Z_DATA_ERROR)
s->mode = BAD;
r = t;
LEAVE
}
Tracev((stderr, "inflate: trees ok\n"));
if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
{
r = Z_MEM_ERROR;
LEAVE
}
s->sub.decode.codes = c;
}
s->mode = CODES;
case CODES:
UPDATE
if ((r = inflate_codes(s, z, r)) != Z_STREAM_END)
return inflate_flush(s, z, r);
r = Z_OK;
inflate_codes_free(s->sub.decode.codes, z);
LOAD
Tracev((stderr, "inflate: codes end, %lu total out\n",
z->total_out + (q >= s->read ? q - s->read :
(s->end - s->read) + (q - s->window))));
if (!s->last)
{
s->mode = TYPE;
break;
}
s->mode = DRY;
case DRY:
FLUSH
if (s->read != s->write)
LEAVE
s->mode = DONE;
case DONE:
r = Z_STREAM_END;
LEAVE
case BAD:
r = Z_DATA_ERROR;
LEAVE
default:
r = Z_STREAM_ERROR;
LEAVE
}
}
int inflate_blocks_free(inflate_blocks_statef *s, z_streamp z)
{
inflate_blocks_reset(s, z, Z_NULL);
ZFREE(z, s->window);
ZFREE(z, s->hufts);
ZFREE(z, s);
Tracev((stderr, "inflate: blocks freed\n"));
return Z_OK;
}
/* Returns true if inflate is currently at the end of a block generated
* by Z_SYNC_FLUSH or Z_FULL_FLUSH.
* IN assertion: s != Z_NULL
*/
int inflate_blocks_sync_point(inflate_blocks_statef *s)
{
return s->mode == LENS;
}
/* infcodes.c -- process literals and length/distance pairs
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* simplify the use of the inflate_huft type with some defines */
#define exop word.what.Exop
#define bits word.what.Bits
typedef enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
START, /* x: set up for LEN */
LEN, /* i: get length/literal/eob next */
LENEXT, /* i: getting length extra (have base) */
DIST, /* i: get distance next */
DISTEXT, /* i: getting distance extra */
COPY, /* o: copying bytes in window, waiting for space */
LIT, /* o: got literal, waiting for output space */
WASH, /* o: got eob, possibly still output waiting */
END, /* x: got eob and all data flushed */
BADCODE} /* x: got error */
inflate_codes_mode;
/* inflate codes private state */
struct inflate_codes_state {
/* mode */
inflate_codes_mode mode; /* current inflate_codes mode */
/* mode dependent information */
uInt len;
union {
struct {
inflate_huft *tree; /* pointer into tree */
uInt need; /* bits needed */
} code; /* if LEN or DIST, where in tree */
uInt lit; /* if LIT, literal */
struct {
uInt get; /* bits to get for extra */
uInt dist; /* distance back to copy from */
} copy; /* if EXT or COPY, where and how much */
} sub; /* submode */
/* mode independent information */
Byte lbits; /* ltree bits decoded per branch */
Byte dbits; /* dtree bits decoder per branch */
inflate_huft *ltree; /* literal/length/eob tree */
inflate_huft *dtree; /* distance tree */
};
inflate_codes_statef *inflate_codes_new(
uInt bl,
uInt bd,
inflate_huft *tl,
inflate_huft *td, /* need separate declaration for Borland C++ */
z_streamp z)
{
inflate_codes_statef *c;
if ((c = (inflate_codes_statef *)
ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL)
{
c->mode = START;
c->lbits = (Byte)bl;
c->dbits = (Byte)bd;
c->ltree = tl;
c->dtree = td;
Tracev((stderr, "inflate: codes new\n"));
}
return c;
}
int inflate_codes(inflate_blocks_statef *s, z_streamp z, int r)
{
uInt j; /* temporary storage */
inflate_huft *t; /* temporary pointer */
uInt e; /* extra bits or operation */
uLong b; /* bit buffer */
uInt k; /* bits in bit buffer */
Bytef *p; /* input data pointer */
uInt n; /* bytes available there */
Bytef *q; /* output window write pointer */
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