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-rw-r--r--libs/zlib/src/adler32.c213
1 files changed, 110 insertions, 103 deletions
diff --git a/libs/zlib/src/adler32.c b/libs/zlib/src/adler32.c
index ecead35379..d0be4380a3 100644
--- a/libs/zlib/src/adler32.c
+++ b/libs/zlib/src/adler32.c
@@ -1,5 +1,5 @@
/* adler32.c -- compute the Adler-32 checksum of a data stream
- * Copyright (C) 1995-2011 Mark Adler
+ * Copyright (C) 1995-2011, 2016 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
@@ -7,11 +7,9 @@
#include "zutil.h"
-#define local static
-
local uLong adler32_combine_ OF((uLong adler1, uLong adler2, z_off64_t len2));
-#define BASE 65521 /* largest prime smaller than 65536 */
+#define BASE 65521U /* 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 */
@@ -61,119 +59,128 @@ local uLong adler32_combine_ OF((uLong adler1, uLong adler2, z_off64_t len2));
# define MOD63(a) a %= BASE
#endif
- /* ========================================================================= */
+/* ========================================================================= */
+uLong ZEXPORT adler32_z(adler, buf, len)
+ uLong adler;
+ const Bytef *buf;
+ z_size_t 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);
+ }
+
+ /* initial Adler-32 value (deferred check for len == 1 speed) */
+ 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;
+ DO16(buf);
+ buf += 16;
+ }
+ while (len--) {
+ adler += *buf++;
+ sum2 += adler;
+ }
+ MOD(adler);
+ MOD(sum2);
+ }
+
+ /* return recombined sums */
+ return adler | (sum2 << 16);
+}
+
+/* ========================================================================= */
uLong ZEXPORT adler32(adler, buf, len)
-uLong adler;
-const Bytef *buf;
-uInt len;
+ uLong adler;
+ const Bytef *buf;
+ 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);
- }
-
- /* initial Adler-32 value (deferred check for len == 1 speed) */
- 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;
- DO16(buf);
- buf += 16;
- }
- while (len--) {
- adler += *buf++;
- sum2 += adler;
- }
- MOD(adler);
- MOD(sum2);
- }
-
- /* return recombined sums */
- return adler | (sum2 << 16);
+ return adler32_z(adler, buf, len);
}
/* ========================================================================= */
local uLong adler32_combine_(adler1, adler2, len2)
-uLong adler1;
-uLong adler2;
-z_off64_t len2;
+ 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 >= (BASE << 1)) sum2 -= (BASE << 1);
- if (sum2 >= BASE) sum2 -= BASE;
- return sum1 | (sum2 << 16);
+ 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);
}
/* ========================================================================= */
uLong ZEXPORT adler32_combine(adler1, adler2, len2)
-uLong adler1;
-uLong adler2;
-z_off_t len2;
+ uLong adler1;
+ uLong adler2;
+ z_off_t len2;
{
- return adler32_combine_(adler1, adler2, len2);
+ return adler32_combine_(adler1, adler2, len2);
}
uLong ZEXPORT adler32_combine64(adler1, adler2, len2)
-uLong adler1;
-uLong adler2;
-z_off64_t len2;
+ uLong adler1;
+ uLong adler2;
+ z_off64_t len2;
{
- return adler32_combine_(adler1, adler2, len2);
+ return adler32_combine_(adler1, adler2, len2);
}
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