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zlib 1.2.2.1

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This commit is contained in:
Mark Adler
2011-09-09 23:24:24 -07:00
parent 79fbcdc939
commit 9811b53dd9
36 changed files with 1334 additions and 429 deletions
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24
adler32.c
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@@ -1,5 +1,5 @@
/* adler32.c -- compute the Adler-32 checksum of a data stream
* Copyright (C) 1995-2003 Mark Adler
* Copyright (C) 1995-2004 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
@@ -72,3 +72,25 @@ uLong ZEXPORT adler32(adler, buf, len)
}
return (s2 << 16) | s1;
}
/* ========================================================================= */
uLong ZEXPORT adler32_combine(adler1, adler2, len2)
uLong adler1;
uLong adler2;
uLong len2;
{
unsigned long s1;
unsigned long s2;
len2 %= BASE;
s1 = adler1 & 0xffff;
s2 = len2 * s1;
MOD(s2);
s1 += (adler2 & 0xffff) + BASE - 1;
s2 += ((adler1 >> 16) & 0xffff) + ((adler2 >> 16) & 0xffff) + BASE - len2;
if (s1 > BASE) s1 -= BASE;
if (s1 > BASE) s1 -= BASE;
if (s2 > (BASE << 1)) s2 -= (BASE << 1);
if (s2 > BASE) s2 -= BASE;
return (s2 << 16) | s1;
}