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zlib 0.93

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This commit is contained in:
Mark Adler
2011-09-09 23:08:28 -07:00
parent bdde4e09d2
commit 6b834a58bd
16 changed files with 253 additions and 203 deletions
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155
inffast.c
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@@ -17,10 +17,6 @@ struct inflate_codes_state {int dummy;}; /* for buggy compilers */
#define bits word.what.Bits
/* macros for bit input with no checking and for returning unused bytes */
#ifdef DEBUG
# undef NEXTBYTE
# define NEXTBYTE (n--?0:fprintf(stderr,"inffast underrun\n"),*p++)
#endif
#define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}}
#define UNGRAB {n+=(c=k>>3);p-=c;k&=7;}
@@ -36,7 +32,7 @@ struct inflate_blocks_state *s;
z_stream *z;
{
inflate_huft *t; /* temporary pointer */
int e; /* extra bits or operation */
uInt e; /* extra bits or operation */
uLong b; /* bit buffer */
uInt k; /* bits in bit buffer */
Byte *p; /* input data pointer */
@@ -52,7 +48,7 @@ z_stream *z;
/* load input, output, bit values */
LOAD
/* initialize masks in registers */
/* initialize masks */
ml = inflate_mask[bl];
md = inflate_mask[bd];
@@ -60,93 +56,106 @@ z_stream *z;
do { /* assume called with m >= 258 && n >= 10 */
/* get literal/length code */
GRABBITS(20) /* max bits for literal/length code */
if ((e = (t = tl + ((uInt)b & ml))->exop) < 0)
do {
if (e == -128)
{
z->msg = "invalid literal/length code";
UNGRAB
UPDATE
return Z_DATA_ERROR;
}
DUMPBITS(t->bits)
e = -e;
if (e & 64) /* end of block */
{
Tracevv((stderr, "inflate: * end of block\n"));
UNGRAB
UPDATE
return Z_STREAM_END;
}
} while ((e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop) < 0);
DUMPBITS(t->bits)
/* process literal or length (end of block already trapped) */
if (e & 16) /* then it's a literal */
if ((e = (t = tl + ((uInt)b & ml))->exop) == 0)
{
DUMPBITS(t->bits)
Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
"inflate: * literal '%c'\n" :
"inflate: * literal 0x%02x\n", t->base));
*q++ = (Byte)t->base;
m--;
continue;
}
else /* it's a length */
{
/* get length of block to copy (already have extra bits) */
c = t->base + ((uInt)b & inflate_mask[e]);
DUMPBITS(e);
Tracevv((stderr, "inflate: * length %u\n", c));
do {
DUMPBITS(t->bits)
if (e & 16)
{
/* get extra bits for length */
e &= 15;
c = t->base + ((uInt)b & inflate_mask[e]);
DUMPBITS(e)
Tracevv((stderr, "inflate: * length %u\n", c));
/* decode distance base of block to copy */
GRABBITS(15); /* max bits for distance code */
if ((e = (t = td + ((uInt)b & md))->exop) < 0)
/* decode distance base of block to copy */
GRABBITS(15); /* max bits for distance code */
e = (t = td + ((uInt)b & md))->exop;
do {
if (e == -128)
DUMPBITS(t->bits)
if (e & 16)
{
/* get extra bits to add to distance base */
e &= 15;
GRABBITS(e) /* get extra bits (up to 13) */
d = t->base + ((uInt)b & inflate_mask[e]);
DUMPBITS(e)
Tracevv((stderr, "inflate: * distance %u\n", d));
/* do the copy */
m -= c;
if ((uInt)(q - s->window) >= d) /* offset before dest */
{ /* just copy */
r = q - d;
*q++ = *r++; c--; /* minimum count is three, */
*q++ = *r++; c--; /* so unroll loop a little */
}
else /* else offset after destination */
{
e = d - (q - s->window); /* bytes from offset to end */
r = s->end - e; /* pointer to offset */
if (c > e) /* if source crosses, */
{
c -= e; /* copy to end of window */
do {
*q++ = *r++;
} while (--e);
r = s->window; /* copy rest from start of window */
}
}
do { /* copy all or what's left */
*q++ = *r++;
} while (--c);
break;
}
else if ((e & 64) == 0)
e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop;
else
{
z->msg = "invalid distance code";
UNGRAB
UPDATE
return Z_DATA_ERROR;
}
DUMPBITS(t->bits)
e = -e;
} while ((e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop) < 0);
DUMPBITS(t->bits)
/* get extra bits to add to distance base */
GRABBITS((uInt)e) /* get extra bits (up to 13) */
d = t->base + ((uInt)b & inflate_mask[e]);
DUMPBITS(e)
Tracevv((stderr, "inflate: * distance %u\n", d));
/* do the copy */
m -= c;
if ((uInt)(q - s->window) >= d) /* if offset before destination, */
{ /* just copy */
r = q - d;
*q++ = *r++; c--; /* minimum count is three, */
*q++ = *r++; c--; /* so unroll loop a little */
do {
*q++ = *r++;
} while (--c);
} while (1);
break;
}
else /* else offset after destination */
if ((e & 64) == 0)
{
e = d - (q - s->window); /* bytes from offset to end */
r = s->end - e; /* pointer to offset */
if (c > (uInt)e) /* if source crosses, */
if ((e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop) == 0)
{
c -= e; /* copy to end of window */
do {
*q++ = *r++;
} while (--e);
r = s->window; /* copy rest from start of window */
DUMPBITS(t->bits)
Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
"inflate: * literal '%c'\n" :
"inflate: * literal 0x%02x\n", t->base));
*q++ = (Byte)t->base;
m--;
break;
}
do { /* copy all or what's left */
*q++ = *r++;
} while (--c);
}
}
else if (e & 32)
{
Tracevv((stderr, "inflate: * end of block\n"));
UNGRAB
UPDATE
return Z_STREAM_END;
}
else
{
z->msg = "invalid literal/length code";
UNGRAB
UPDATE
return Z_DATA_ERROR;
}
} while (1);
} while (m >= 258 && n >= 10);
/* not enough input or output--restore pointers and return */