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-rw-r--r--[-rwxr-xr-x]utils/zenutils/libraries/zlib123/zlib/adler32.c298
1 files changed, 149 insertions, 149 deletions
diff --git a/utils/zenutils/libraries/zlib123/zlib/adler32.c b/utils/zenutils/libraries/zlib123/zlib/adler32.c
index f201d6701e..007ba26277 100755..100644
--- a/utils/zenutils/libraries/zlib123/zlib/adler32.c
+++ b/utils/zenutils/libraries/zlib123/zlib/adler32.c
@@ -1,149 +1,149 @@
1/* adler32.c -- compute the Adler-32 checksum of a data stream 1/* adler32.c -- compute the Adler-32 checksum of a data stream
2 * Copyright (C) 1995-2004 Mark Adler 2 * Copyright (C) 1995-2004 Mark Adler
3 * For conditions of distribution and use, see copyright notice in zlib.h 3 * For conditions of distribution and use, see copyright notice in zlib.h
4 */ 4 */
5 5
6/* @(#) $Id$ */ 6/* @(#) $Id$ */
7 7
8#define ZLIB_INTERNAL 8#define ZLIB_INTERNAL
9#include "zlib.h" 9#include "zlib.h"
10 10
11#define BASE 65521UL /* largest prime smaller than 65536 */ 11#define BASE 65521UL /* largest prime smaller than 65536 */
12#define NMAX 5552 12#define NMAX 5552
13/* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */ 13/* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
14 14
15#define DO1(buf,i) {adler += (buf)[i]; sum2 += adler;} 15#define DO1(buf,i) {adler += (buf)[i]; sum2 += adler;}
16#define DO2(buf,i) DO1(buf,i); DO1(buf,i+1); 16#define DO2(buf,i) DO1(buf,i); DO1(buf,i+1);
17#define DO4(buf,i) DO2(buf,i); DO2(buf,i+2); 17#define DO4(buf,i) DO2(buf,i); DO2(buf,i+2);
18#define DO8(buf,i) DO4(buf,i); DO4(buf,i+4); 18#define DO8(buf,i) DO4(buf,i); DO4(buf,i+4);
19#define DO16(buf) DO8(buf,0); DO8(buf,8); 19#define DO16(buf) DO8(buf,0); DO8(buf,8);
20 20
21/* use NO_DIVIDE if your processor does not do division in hardware */ 21/* use NO_DIVIDE if your processor does not do division in hardware */
22#ifdef NO_DIVIDE 22#ifdef NO_DIVIDE
23# define MOD(a) \ 23# define MOD(a) \
24 do { \ 24 do { \
25 if (a >= (BASE << 16)) a -= (BASE << 16); \ 25 if (a >= (BASE << 16)) a -= (BASE << 16); \
26 if (a >= (BASE << 15)) a -= (BASE << 15); \ 26 if (a >= (BASE << 15)) a -= (BASE << 15); \
27 if (a >= (BASE << 14)) a -= (BASE << 14); \ 27 if (a >= (BASE << 14)) a -= (BASE << 14); \
28 if (a >= (BASE << 13)) a -= (BASE << 13); \ 28 if (a >= (BASE << 13)) a -= (BASE << 13); \
29 if (a >= (BASE << 12)) a -= (BASE << 12); \ 29 if (a >= (BASE << 12)) a -= (BASE << 12); \
30 if (a >= (BASE << 11)) a -= (BASE << 11); \ 30 if (a >= (BASE << 11)) a -= (BASE << 11); \
31 if (a >= (BASE << 10)) a -= (BASE << 10); \ 31 if (a >= (BASE << 10)) a -= (BASE << 10); \
32 if (a >= (BASE << 9)) a -= (BASE << 9); \ 32 if (a >= (BASE << 9)) a -= (BASE << 9); \
33 if (a >= (BASE << 8)) a -= (BASE << 8); \ 33 if (a >= (BASE << 8)) a -= (BASE << 8); \
34 if (a >= (BASE << 7)) a -= (BASE << 7); \ 34 if (a >= (BASE << 7)) a -= (BASE << 7); \
35 if (a >= (BASE << 6)) a -= (BASE << 6); \ 35 if (a >= (BASE << 6)) a -= (BASE << 6); \
36 if (a >= (BASE << 5)) a -= (BASE << 5); \ 36 if (a >= (BASE << 5)) a -= (BASE << 5); \
37 if (a >= (BASE << 4)) a -= (BASE << 4); \ 37 if (a >= (BASE << 4)) a -= (BASE << 4); \
38 if (a >= (BASE << 3)) a -= (BASE << 3); \ 38 if (a >= (BASE << 3)) a -= (BASE << 3); \
39 if (a >= (BASE << 2)) a -= (BASE << 2); \ 39 if (a >= (BASE << 2)) a -= (BASE << 2); \
40 if (a >= (BASE << 1)) a -= (BASE << 1); \ 40 if (a >= (BASE << 1)) a -= (BASE << 1); \
41 if (a >= BASE) a -= BASE; \ 41 if (a >= BASE) a -= BASE; \
42 } while (0) 42 } while (0)
43# define MOD4(a) \ 43# define MOD4(a) \
44 do { \ 44 do { \
45 if (a >= (BASE << 4)) a -= (BASE << 4); \ 45 if (a >= (BASE << 4)) a -= (BASE << 4); \
46 if (a >= (BASE << 3)) a -= (BASE << 3); \ 46 if (a >= (BASE << 3)) a -= (BASE << 3); \
47 if (a >= (BASE << 2)) a -= (BASE << 2); \ 47 if (a >= (BASE << 2)) a -= (BASE << 2); \
48 if (a >= (BASE << 1)) a -= (BASE << 1); \ 48 if (a >= (BASE << 1)) a -= (BASE << 1); \
49 if (a >= BASE) a -= BASE; \ 49 if (a >= BASE) a -= BASE; \
50 } while (0) 50 } while (0)
51#else 51#else
52# define MOD(a) a %= BASE 52# define MOD(a) a %= BASE
53# define MOD4(a) a %= BASE 53# define MOD4(a) a %= BASE
54#endif 54#endif
55 55
56/* ========================================================================= */ 56/* ========================================================================= */
57uLong ZEXPORT adler32(adler, buf, len) 57uLong ZEXPORT adler32(adler, buf, len)
58 uLong adler; 58 uLong adler;
59 const Bytef *buf; 59 const Bytef *buf;
60 uInt len; 60 uInt len;
61{ 61{
62 unsigned long sum2; 62 unsigned long sum2;
63 unsigned n; 63 unsigned n;
64 64
65 /* split Adler-32 into component sums */ 65 /* split Adler-32 into component sums */
66 sum2 = (adler >> 16) & 0xffff; 66 sum2 = (adler >> 16) & 0xffff;
67 adler &= 0xffff; 67 adler &= 0xffff;
68 68
69 /* in case user likes doing a byte at a time, keep it fast */ 69 /* in case user likes doing a byte at a time, keep it fast */
70 if (len == 1) { 70 if (len == 1) {
71 adler += buf[0]; 71 adler += buf[0];
72 if (adler >= BASE) 72 if (adler >= BASE)
73 adler -= BASE; 73 adler -= BASE;
74 sum2 += adler; 74 sum2 += adler;
75 if (sum2 >= BASE) 75 if (sum2 >= BASE)
76 sum2 -= BASE; 76 sum2 -= BASE;
77 return adler | (sum2 << 16); 77 return adler | (sum2 << 16);
78 } 78 }
79 79
80 /* initial Adler-32 value (deferred check for len == 1 speed) */ 80 /* initial Adler-32 value (deferred check for len == 1 speed) */
81 if (buf == Z_NULL) 81 if (buf == Z_NULL)
82 return 1L; 82 return 1L;
83 83
84 /* in case short lengths are provided, keep it somewhat fast */ 84 /* in case short lengths are provided, keep it somewhat fast */
85 if (len < 16) { 85 if (len < 16) {
86 while (len--) { 86 while (len--) {
87 adler += *buf++; 87 adler += *buf++;
88 sum2 += adler; 88 sum2 += adler;
89 } 89 }
90 if (adler >= BASE) 90 if (adler >= BASE)
91 adler -= BASE; 91 adler -= BASE;
92 MOD4(sum2); /* only added so many BASE's */ 92 MOD4(sum2); /* only added so many BASE's */
93 return adler | (sum2 << 16); 93 return adler | (sum2 << 16);
94 } 94 }
95 95
96 /* do length NMAX blocks -- requires just one modulo operation */ 96 /* do length NMAX blocks -- requires just one modulo operation */
97 while (len >= NMAX) { 97 while (len >= NMAX) {
98 len -= NMAX; 98 len -= NMAX;
99 n = NMAX / 16; /* NMAX is divisible by 16 */ 99 n = NMAX / 16; /* NMAX is divisible by 16 */
100 do { 100 do {
101 DO16(buf); /* 16 sums unrolled */ 101 DO16(buf); /* 16 sums unrolled */
102 buf += 16; 102 buf += 16;
103 } while (--n); 103 } while (--n);
104 MOD(adler); 104 MOD(adler);
105 MOD(sum2); 105 MOD(sum2);
106 } 106 }
107 107
108 /* do remaining bytes (less than NMAX, still just one modulo) */ 108 /* do remaining bytes (less than NMAX, still just one modulo) */
109 if (len) { /* avoid modulos if none remaining */ 109 if (len) { /* avoid modulos if none remaining */
110 while (len >= 16) { 110 while (len >= 16) {
111 len -= 16; 111 len -= 16;
112 DO16(buf); 112 DO16(buf);
113 buf += 16; 113 buf += 16;
114 } 114 }
115 while (len--) { 115 while (len--) {
116 adler += *buf++; 116 adler += *buf++;
117 sum2 += adler; 117 sum2 += adler;
118 } 118 }
119 MOD(adler); 119 MOD(adler);
120 MOD(sum2); 120 MOD(sum2);
121 } 121 }
122 122
123 /* return recombined sums */ 123 /* return recombined sums */
124 return adler | (sum2 << 16); 124 return adler | (sum2 << 16);
125} 125}
126 126
127/* ========================================================================= */ 127/* ========================================================================= */
128uLong ZEXPORT adler32_combine(adler1, adler2, len2) 128uLong ZEXPORT adler32_combine(adler1, adler2, len2)
129 uLong adler1; 129 uLong adler1;
130 uLong adler2; 130 uLong adler2;
131 z_off_t len2; 131 z_off_t len2;
132{ 132{
133 unsigned long sum1; 133 unsigned long sum1;
134 unsigned long sum2; 134 unsigned long sum2;
135 unsigned rem; 135 unsigned rem;
136 136
137 /* the derivation of this formula is left as an exercise for the reader */ 137 /* the derivation of this formula is left as an exercise for the reader */
138 rem = (unsigned)(len2 % BASE); 138 rem = (unsigned)(len2 % BASE);
139 sum1 = adler1 & 0xffff; 139 sum1 = adler1 & 0xffff;
140 sum2 = rem * sum1; 140 sum2 = rem * sum1;
141 MOD(sum2); 141 MOD(sum2);
142 sum1 += (adler2 & 0xffff) + BASE - 1; 142 sum1 += (adler2 & 0xffff) + BASE - 1;
143 sum2 += ((adler1 >> 16) & 0xffff) + ((adler2 >> 16) & 0xffff) + BASE - rem; 143 sum2 += ((adler1 >> 16) & 0xffff) + ((adler2 >> 16) & 0xffff) + BASE - rem;
144 if (sum1 > BASE) sum1 -= BASE; 144 if (sum1 > BASE) sum1 -= BASE;
145 if (sum1 > BASE) sum1 -= BASE; 145 if (sum1 > BASE) sum1 -= BASE;
146 if (sum2 > (BASE << 1)) sum2 -= (BASE << 1); 146 if (sum2 > (BASE << 1)) sum2 -= (BASE << 1);
147 if (sum2 > BASE) sum2 -= BASE; 147 if (sum2 > BASE) sum2 -= BASE;
148 return sum1 | (sum2 << 16); 148 return sum1 | (sum2 << 16);
149} 149}
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