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-rw-r--r--Build/source/libs/freetype2/freetype-src/src/gzip/adler32.c188
1 files changed, 22 insertions, 166 deletions
diff --git a/Build/source/libs/freetype2/freetype-src/src/gzip/adler32.c b/Build/source/libs/freetype2/freetype-src/src/gzip/adler32.c
index aa032e1ddf6..c53f9dd125d 100644
--- a/Build/source/libs/freetype2/freetype-src/src/gzip/adler32.c
+++ b/Build/source/libs/freetype2/freetype-src/src/gzip/adler32.c
@@ -1,192 +1,48 @@
/* adler32.c -- compute the Adler-32 checksum of a data stream
- * Copyright (C) 1995-2011, 2016 Mark Adler
+ * Copyright (C) 1995-2002 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* @(#) $Id$ */
-#include "zutil.h"
+#include "zlib.h"
-#ifndef Z_FREETYPE
-local uLong adler32_combine_ OF((uLong adler1, uLong adler2, z_off64_t len2));
-#endif
-
-#define BASE 65521U /* largest prime smaller than 65536 */
+#define BASE 65521L /* largest prime smaller than 65536 */
#define NMAX 5552
/* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
-#define DO1(buf,i) {adler += (buf)[i]; sum2 += adler;}
+#define DO1(buf,i) {s1 += buf[i]; s2 += s1;}
#define DO2(buf,i) DO1(buf,i); DO1(buf,i+1);
#define DO4(buf,i) DO2(buf,i); DO2(buf,i+2);
#define DO8(buf,i) DO4(buf,i); DO4(buf,i+4);
#define DO16(buf) DO8(buf,0); DO8(buf,8);
-/* use NO_DIVIDE if your processor does not do division in hardware --
- try it both ways to see which is faster */
-#ifdef NO_DIVIDE
-/* note that this assumes BASE is 65521, where 65536 % 65521 == 15
- (thank you to John Reiser for pointing this out) */
-# define CHOP(a) \
- do { \
- unsigned long tmp = a >> 16; \
- a &= 0xffffUL; \
- a += (tmp << 4) - tmp; \
- } while (0)
-# define MOD28(a) \
- do { \
- CHOP(a); \
- if (a >= BASE) a -= BASE; \
- } while (0)
-# define MOD(a) \
- do { \
- CHOP(a); \
- MOD28(a); \
- } while (0)
-# define MOD63(a) \
- do { /* this assumes a is not negative */ \
- z_off64_t tmp = a >> 32; \
- a &= 0xffffffffL; \
- a += (tmp << 8) - (tmp << 5) + tmp; \
- tmp = a >> 16; \
- a &= 0xffffL; \
- a += (tmp << 4) - tmp; \
- tmp = a >> 16; \
- a &= 0xffffL; \
- a += (tmp << 4) - tmp; \
- if (a >= BASE) a -= BASE; \
- } while (0)
-#else
-# define MOD(a) a %= BASE
-# define MOD28(a) a %= BASE
-# define MOD63(a) a %= BASE
-#endif
-
/* ========================================================================= */
-uLong ZEXPORT adler32_z(
+ZEXPORT(uLong) adler32( /* adler, buf, len) */
uLong adler,
const Bytef *buf,
- z_size_t len)
+ uInt len )
{
- unsigned long sum2;
- unsigned n;
-
- /* split Adler-32 into component sums */
- sum2 = (adler >> 16) & 0xffff;
- adler &= 0xffff;
-
- /* in case user likes doing a byte at a time, keep it fast */
- if (len == 1) {
- adler += buf[0];
- if (adler >= BASE)
- adler -= BASE;
- sum2 += adler;
- if (sum2 >= BASE)
- sum2 -= BASE;
- return adler | (sum2 << 16);
- }
+ unsigned long s1 = adler & 0xffff;
+ unsigned long s2 = (adler >> 16) & 0xffff;
+ int k;
- /* initial Adler-32 value (deferred check for len == 1 speed) */
- if (buf == Z_NULL)
- return 1L;
+ if (buf == Z_NULL) return 1L;
- /* in case short lengths are provided, keep it somewhat fast */
- if (len < 16) {
- while (len--) {
- adler += *buf++;
- sum2 += adler;
- }
- if (adler >= BASE)
- adler -= BASE;
- MOD28(sum2); /* only added so many BASE's */
- return adler | (sum2 << 16);
- }
-
- /* do length NMAX blocks -- requires just one modulo operation */
- while (len >= NMAX) {
- len -= NMAX;
- n = NMAX / 16; /* NMAX is divisible by 16 */
- do {
- DO16(buf); /* 16 sums unrolled */
- buf += 16;
- } while (--n);
- MOD(adler);
- MOD(sum2);
- }
-
- /* do remaining bytes (less than NMAX, still just one modulo) */
- if (len) { /* avoid modulos if none remaining */
- while (len >= 16) {
- len -= 16;
+ while (len > 0) {
+ k = len < NMAX ? len : NMAX;
+ len -= k;
+ while (k >= 16) {
DO16(buf);
buf += 16;
+ k -= 16;
}
- while (len--) {
- adler += *buf++;
- sum2 += adler;
- }
- MOD(adler);
- MOD(sum2);
+ if (k != 0) do {
+ s1 += *buf++;
+ s2 += s1;
+ } while (--k);
+ s1 %= BASE;
+ s2 %= BASE;
}
-
- /* return recombined sums */
- return adler | (sum2 << 16);
-}
-
-/* ========================================================================= */
-uLong ZEXPORT adler32(
- uLong adler,
- const Bytef *buf,
- uInt len)
-{
- return adler32_z(adler, buf, len);
-}
-
-#ifndef Z_FREETYPE
-
-/* ========================================================================= */
-local uLong adler32_combine_(
- uLong adler1,
- uLong adler2,
- z_off64_t len2)
-{
- unsigned long sum1;
- unsigned long sum2;
- unsigned rem;
-
- /* for negative len, return invalid adler32 as a clue for debugging */
- if (len2 < 0)
- return 0xffffffffUL;
-
- /* the derivation of this formula is left as an exercise for the reader */
- MOD63(len2); /* assumes len2 >= 0 */
- rem = (unsigned)len2;
- sum1 = adler1 & 0xffff;
- sum2 = rem * sum1;
- MOD(sum2);
- sum1 += (adler2 & 0xffff) + BASE - 1;
- sum2 += ((adler1 >> 16) & 0xffff) + ((adler2 >> 16) & 0xffff) + BASE - rem;
- if (sum1 >= BASE) sum1 -= BASE;
- if (sum1 >= BASE) sum1 -= BASE;
- if (sum2 >= ((unsigned long)BASE << 1)) sum2 -= ((unsigned long)BASE << 1);
- if (sum2 >= BASE) sum2 -= BASE;
- return sum1 | (sum2 << 16);
+ return (s2 << 16) | s1;
}
-
-/* ========================================================================= */
-uLong ZEXPORT adler32_combine(
- uLong adler1,
- uLong adler2,
- z_off_t len2)
-{
- return adler32_combine_(adler1, adler2, len2);
-}
-
-uLong ZEXPORT adler32_combine64(
- uLong adler1,
- uLong adler2,
- z_off64_t len2)
-{
- return adler32_combine_(adler1, adler2, len2);
-}
-
-#endif /* !Z_FREETYPE */