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author | David Walter Seikel | 2013-01-13 18:54:10 +1000 |
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committer | David Walter Seikel | 2013-01-13 18:54:10 +1000 |
commit | 959831f4ef5a3e797f576c3de08cd65032c997ad (patch) | |
tree | e7351908be5995f0b325b2ebeaa02d5a34b82583 /libraries/irrlicht-1.8/source/Irrlicht/zlib/crc32.c | |
parent | Add info about changes to Irrlicht. (diff) | |
download | SledjHamr-959831f4ef5a3e797f576c3de08cd65032c997ad.zip SledjHamr-959831f4ef5a3e797f576c3de08cd65032c997ad.tar.gz SledjHamr-959831f4ef5a3e797f576c3de08cd65032c997ad.tar.bz2 SledjHamr-959831f4ef5a3e797f576c3de08cd65032c997ad.tar.xz |
Remove damned ancient DOS line endings from Irrlicht. Hopefully I did not go overboard.
Diffstat (limited to '')
-rw-r--r-- | libraries/irrlicht-1.8/source/Irrlicht/zlib/crc32.c | 850 |
1 files changed, 425 insertions, 425 deletions
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/zlib/crc32.c b/libraries/irrlicht-1.8/source/Irrlicht/zlib/crc32.c index 95a30f1..979a719 100644 --- a/libraries/irrlicht-1.8/source/Irrlicht/zlib/crc32.c +++ b/libraries/irrlicht-1.8/source/Irrlicht/zlib/crc32.c | |||
@@ -1,425 +1,425 @@ | |||
1 | /* crc32.c -- compute the CRC-32 of a data stream | 1 | /* crc32.c -- compute the CRC-32 of a data stream |
2 | * Copyright (C) 1995-2006, 2010, 2011, 2012 Mark Adler | 2 | * Copyright (C) 1995-2006, 2010, 2011, 2012 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 | * Thanks to Rodney Brown <rbrown64@csc.com.au> for his contribution of faster | 5 | * Thanks to Rodney Brown <rbrown64@csc.com.au> for his contribution of faster |
6 | * CRC methods: exclusive-oring 32 bits of data at a time, and pre-computing | 6 | * CRC methods: exclusive-oring 32 bits of data at a time, and pre-computing |
7 | * tables for updating the shift register in one step with three exclusive-ors | 7 | * tables for updating the shift register in one step with three exclusive-ors |
8 | * instead of four steps with four exclusive-ors. This results in about a | 8 | * instead of four steps with four exclusive-ors. This results in about a |
9 | * factor of two increase in speed on a Power PC G4 (PPC7455) using gcc -O3. | 9 | * factor of two increase in speed on a Power PC G4 (PPC7455) using gcc -O3. |
10 | */ | 10 | */ |
11 | 11 | ||
12 | /* @(#) $Id$ */ | 12 | /* @(#) $Id$ */ |
13 | 13 | ||
14 | /* | 14 | /* |
15 | Note on the use of DYNAMIC_CRC_TABLE: there is no mutex or semaphore | 15 | Note on the use of DYNAMIC_CRC_TABLE: there is no mutex or semaphore |
16 | protection on the static variables used to control the first-use generation | 16 | protection on the static variables used to control the first-use generation |
17 | of the crc tables. Therefore, if you #define DYNAMIC_CRC_TABLE, you should | 17 | of the crc tables. Therefore, if you #define DYNAMIC_CRC_TABLE, you should |
18 | first call get_crc_table() to initialize the tables before allowing more than | 18 | first call get_crc_table() to initialize the tables before allowing more than |
19 | one thread to use crc32(). | 19 | one thread to use crc32(). |
20 | 20 | ||
21 | DYNAMIC_CRC_TABLE and MAKECRCH can be #defined to write out crc32.h. | 21 | DYNAMIC_CRC_TABLE and MAKECRCH can be #defined to write out crc32.h. |
22 | */ | 22 | */ |
23 | 23 | ||
24 | #ifdef MAKECRCH | 24 | #ifdef MAKECRCH |
25 | # include <stdio.h> | 25 | # include <stdio.h> |
26 | # ifndef DYNAMIC_CRC_TABLE | 26 | # ifndef DYNAMIC_CRC_TABLE |
27 | # define DYNAMIC_CRC_TABLE | 27 | # define DYNAMIC_CRC_TABLE |
28 | # endif /* !DYNAMIC_CRC_TABLE */ | 28 | # endif /* !DYNAMIC_CRC_TABLE */ |
29 | #endif /* MAKECRCH */ | 29 | #endif /* MAKECRCH */ |
30 | 30 | ||
31 | #include "zutil.h" /* for STDC and FAR definitions */ | 31 | #include "zutil.h" /* for STDC and FAR definitions */ |
32 | 32 | ||
33 | #define local static | 33 | #define local static |
34 | 34 | ||
35 | /* Definitions for doing the crc four data bytes at a time. */ | 35 | /* Definitions for doing the crc four data bytes at a time. */ |
36 | #if !defined(NOBYFOUR) && defined(Z_U4) | 36 | #if !defined(NOBYFOUR) && defined(Z_U4) |
37 | # define BYFOUR | 37 | # define BYFOUR |
38 | #endif | 38 | #endif |
39 | #ifdef BYFOUR | 39 | #ifdef BYFOUR |
40 | local unsigned long crc32_little OF((unsigned long, | 40 | local unsigned long crc32_little OF((unsigned long, |
41 | const unsigned char FAR *, unsigned)); | 41 | const unsigned char FAR *, unsigned)); |
42 | local unsigned long crc32_big OF((unsigned long, | 42 | local unsigned long crc32_big OF((unsigned long, |
43 | const unsigned char FAR *, unsigned)); | 43 | const unsigned char FAR *, unsigned)); |
44 | # define TBLS 8 | 44 | # define TBLS 8 |
45 | #else | 45 | #else |
46 | # define TBLS 1 | 46 | # define TBLS 1 |
47 | #endif /* BYFOUR */ | 47 | #endif /* BYFOUR */ |
48 | 48 | ||
49 | /* Local functions for crc concatenation */ | 49 | /* Local functions for crc concatenation */ |
50 | local unsigned long gf2_matrix_times OF((unsigned long *mat, | 50 | local unsigned long gf2_matrix_times OF((unsigned long *mat, |
51 | unsigned long vec)); | 51 | unsigned long vec)); |
52 | local void gf2_matrix_square OF((unsigned long *square, unsigned long *mat)); | 52 | local void gf2_matrix_square OF((unsigned long *square, unsigned long *mat)); |
53 | local uLong crc32_combine_ OF((uLong crc1, uLong crc2, z_off64_t len2)); | 53 | local uLong crc32_combine_ OF((uLong crc1, uLong crc2, z_off64_t len2)); |
54 | 54 | ||
55 | 55 | ||
56 | #ifdef DYNAMIC_CRC_TABLE | 56 | #ifdef DYNAMIC_CRC_TABLE |
57 | 57 | ||
58 | local volatile int crc_table_empty = 1; | 58 | local volatile int crc_table_empty = 1; |
59 | local z_crc_t FAR crc_table[TBLS][256]; | 59 | local z_crc_t FAR crc_table[TBLS][256]; |
60 | local void make_crc_table OF((void)); | 60 | local void make_crc_table OF((void)); |
61 | #ifdef MAKECRCH | 61 | #ifdef MAKECRCH |
62 | local void write_table OF((FILE *, const z_crc_t FAR *)); | 62 | local void write_table OF((FILE *, const z_crc_t FAR *)); |
63 | #endif /* MAKECRCH */ | 63 | #endif /* MAKECRCH */ |
64 | /* | 64 | /* |
65 | Generate tables for a byte-wise 32-bit CRC calculation on the polynomial: | 65 | Generate tables for a byte-wise 32-bit CRC calculation on the polynomial: |
66 | x^32+x^26+x^23+x^22+x^16+x^12+x^11+x^10+x^8+x^7+x^5+x^4+x^2+x+1. | 66 | x^32+x^26+x^23+x^22+x^16+x^12+x^11+x^10+x^8+x^7+x^5+x^4+x^2+x+1. |
67 | 67 | ||
68 | Polynomials over GF(2) are represented in binary, one bit per coefficient, | 68 | Polynomials over GF(2) are represented in binary, one bit per coefficient, |
69 | with the lowest powers in the most significant bit. Then adding polynomials | 69 | with the lowest powers in the most significant bit. Then adding polynomials |
70 | is just exclusive-or, and multiplying a polynomial by x is a right shift by | 70 | is just exclusive-or, and multiplying a polynomial by x is a right shift by |
71 | one. If we call the above polynomial p, and represent a byte as the | 71 | one. If we call the above polynomial p, and represent a byte as the |
72 | polynomial q, also with the lowest power in the most significant bit (so the | 72 | polynomial q, also with the lowest power in the most significant bit (so the |
73 | byte 0xb1 is the polynomial x^7+x^3+x+1), then the CRC is (q*x^32) mod p, | 73 | byte 0xb1 is the polynomial x^7+x^3+x+1), then the CRC is (q*x^32) mod p, |
74 | where a mod b means the remainder after dividing a by b. | 74 | where a mod b means the remainder after dividing a by b. |
75 | 75 | ||
76 | This calculation is done using the shift-register method of multiplying and | 76 | This calculation is done using the shift-register method of multiplying and |
77 | taking the remainder. The register is initialized to zero, and for each | 77 | taking the remainder. The register is initialized to zero, and for each |
78 | incoming bit, x^32 is added mod p to the register if the bit is a one (where | 78 | incoming bit, x^32 is added mod p to the register if the bit is a one (where |
79 | x^32 mod p is p+x^32 = x^26+...+1), and the register is multiplied mod p by | 79 | x^32 mod p is p+x^32 = x^26+...+1), and the register is multiplied mod p by |
80 | x (which is shifting right by one and adding x^32 mod p if the bit shifted | 80 | x (which is shifting right by one and adding x^32 mod p if the bit shifted |
81 | out is a one). We start with the highest power (least significant bit) of | 81 | out is a one). We start with the highest power (least significant bit) of |
82 | q and repeat for all eight bits of q. | 82 | q and repeat for all eight bits of q. |
83 | 83 | ||
84 | The first table is simply the CRC of all possible eight bit values. This is | 84 | The first table is simply the CRC of all possible eight bit values. This is |
85 | all the information needed to generate CRCs on data a byte at a time for all | 85 | all the information needed to generate CRCs on data a byte at a time for all |
86 | combinations of CRC register values and incoming bytes. The remaining tables | 86 | combinations of CRC register values and incoming bytes. The remaining tables |
87 | allow for word-at-a-time CRC calculation for both big-endian and little- | 87 | allow for word-at-a-time CRC calculation for both big-endian and little- |
88 | endian machines, where a word is four bytes. | 88 | endian machines, where a word is four bytes. |
89 | */ | 89 | */ |
90 | local void make_crc_table() | 90 | local void make_crc_table() |
91 | { | 91 | { |
92 | z_crc_t c; | 92 | z_crc_t c; |
93 | int n, k; | 93 | int n, k; |
94 | z_crc_t poly; /* polynomial exclusive-or pattern */ | 94 | z_crc_t poly; /* polynomial exclusive-or pattern */ |
95 | /* terms of polynomial defining this crc (except x^32): */ | 95 | /* terms of polynomial defining this crc (except x^32): */ |
96 | static volatile int first = 1; /* flag to limit concurrent making */ | 96 | static volatile int first = 1; /* flag to limit concurrent making */ |
97 | static const unsigned char p[] = {0,1,2,4,5,7,8,10,11,12,16,22,23,26}; | 97 | static const unsigned char p[] = {0,1,2,4,5,7,8,10,11,12,16,22,23,26}; |
98 | 98 | ||
99 | /* See if another task is already doing this (not thread-safe, but better | 99 | /* See if another task is already doing this (not thread-safe, but better |
100 | than nothing -- significantly reduces duration of vulnerability in | 100 | than nothing -- significantly reduces duration of vulnerability in |
101 | case the advice about DYNAMIC_CRC_TABLE is ignored) */ | 101 | case the advice about DYNAMIC_CRC_TABLE is ignored) */ |
102 | if (first) { | 102 | if (first) { |
103 | first = 0; | 103 | first = 0; |
104 | 104 | ||
105 | /* make exclusive-or pattern from polynomial (0xedb88320UL) */ | 105 | /* make exclusive-or pattern from polynomial (0xedb88320UL) */ |
106 | poly = 0; | 106 | poly = 0; |
107 | for (n = 0; n < (int)(sizeof(p)/sizeof(unsigned char)); n++) | 107 | for (n = 0; n < (int)(sizeof(p)/sizeof(unsigned char)); n++) |
108 | poly |= (z_crc_t)1 << (31 - p[n]); | 108 | poly |= (z_crc_t)1 << (31 - p[n]); |
109 | 109 | ||
110 | /* generate a crc for every 8-bit value */ | 110 | /* generate a crc for every 8-bit value */ |
111 | for (n = 0; n < 256; n++) { | 111 | for (n = 0; n < 256; n++) { |
112 | c = (z_crc_t)n; | 112 | c = (z_crc_t)n; |
113 | for (k = 0; k < 8; k++) | 113 | for (k = 0; k < 8; k++) |
114 | c = c & 1 ? poly ^ (c >> 1) : c >> 1; | 114 | c = c & 1 ? poly ^ (c >> 1) : c >> 1; |
115 | crc_table[0][n] = c; | 115 | crc_table[0][n] = c; |
116 | } | 116 | } |
117 | 117 | ||
118 | #ifdef BYFOUR | 118 | #ifdef BYFOUR |
119 | /* generate crc for each value followed by one, two, and three zeros, | 119 | /* generate crc for each value followed by one, two, and three zeros, |
120 | and then the byte reversal of those as well as the first table */ | 120 | and then the byte reversal of those as well as the first table */ |
121 | for (n = 0; n < 256; n++) { | 121 | for (n = 0; n < 256; n++) { |
122 | c = crc_table[0][n]; | 122 | c = crc_table[0][n]; |
123 | crc_table[4][n] = ZSWAP32(c); | 123 | crc_table[4][n] = ZSWAP32(c); |
124 | for (k = 1; k < 4; k++) { | 124 | for (k = 1; k < 4; k++) { |
125 | c = crc_table[0][c & 0xff] ^ (c >> 8); | 125 | c = crc_table[0][c & 0xff] ^ (c >> 8); |
126 | crc_table[k][n] = c; | 126 | crc_table[k][n] = c; |
127 | crc_table[k + 4][n] = ZSWAP32(c); | 127 | crc_table[k + 4][n] = ZSWAP32(c); |
128 | } | 128 | } |
129 | } | 129 | } |
130 | #endif /* BYFOUR */ | 130 | #endif /* BYFOUR */ |
131 | 131 | ||
132 | crc_table_empty = 0; | 132 | crc_table_empty = 0; |
133 | } | 133 | } |
134 | else { /* not first */ | 134 | else { /* not first */ |
135 | /* wait for the other guy to finish (not efficient, but rare) */ | 135 | /* wait for the other guy to finish (not efficient, but rare) */ |
136 | while (crc_table_empty) | 136 | while (crc_table_empty) |
137 | ; | 137 | ; |
138 | } | 138 | } |
139 | 139 | ||
140 | #ifdef MAKECRCH | 140 | #ifdef MAKECRCH |
141 | /* write out CRC tables to crc32.h */ | 141 | /* write out CRC tables to crc32.h */ |
142 | { | 142 | { |
143 | FILE *out; | 143 | FILE *out; |
144 | 144 | ||
145 | out = fopen("crc32.h", "w"); | 145 | out = fopen("crc32.h", "w"); |
146 | if (out == NULL) return; | 146 | if (out == NULL) return; |
147 | fprintf(out, "/* crc32.h -- tables for rapid CRC calculation\n"); | 147 | fprintf(out, "/* crc32.h -- tables for rapid CRC calculation\n"); |
148 | fprintf(out, " * Generated automatically by crc32.c\n */\n\n"); | 148 | fprintf(out, " * Generated automatically by crc32.c\n */\n\n"); |
149 | fprintf(out, "local const z_crc_t FAR "); | 149 | fprintf(out, "local const z_crc_t FAR "); |
150 | fprintf(out, "crc_table[TBLS][256] =\n{\n {\n"); | 150 | fprintf(out, "crc_table[TBLS][256] =\n{\n {\n"); |
151 | write_table(out, crc_table[0]); | 151 | write_table(out, crc_table[0]); |
152 | # ifdef BYFOUR | 152 | # ifdef BYFOUR |
153 | fprintf(out, "#ifdef BYFOUR\n"); | 153 | fprintf(out, "#ifdef BYFOUR\n"); |
154 | for (k = 1; k < 8; k++) { | 154 | for (k = 1; k < 8; k++) { |
155 | fprintf(out, " },\n {\n"); | 155 | fprintf(out, " },\n {\n"); |
156 | write_table(out, crc_table[k]); | 156 | write_table(out, crc_table[k]); |
157 | } | 157 | } |
158 | fprintf(out, "#endif\n"); | 158 | fprintf(out, "#endif\n"); |
159 | # endif /* BYFOUR */ | 159 | # endif /* BYFOUR */ |
160 | fprintf(out, " }\n};\n"); | 160 | fprintf(out, " }\n};\n"); |
161 | fclose(out); | 161 | fclose(out); |
162 | } | 162 | } |
163 | #endif /* MAKECRCH */ | 163 | #endif /* MAKECRCH */ |
164 | } | 164 | } |
165 | 165 | ||
166 | #ifdef MAKECRCH | 166 | #ifdef MAKECRCH |
167 | local void write_table(out, table) | 167 | local void write_table(out, table) |
168 | FILE *out; | 168 | FILE *out; |
169 | const z_crc_t FAR *table; | 169 | const z_crc_t FAR *table; |
170 | { | 170 | { |
171 | int n; | 171 | int n; |
172 | 172 | ||
173 | for (n = 0; n < 256; n++) | 173 | for (n = 0; n < 256; n++) |
174 | fprintf(out, "%s0x%08lxUL%s", n % 5 ? "" : " ", | 174 | fprintf(out, "%s0x%08lxUL%s", n % 5 ? "" : " ", |
175 | (unsigned long)(table[n]), | 175 | (unsigned long)(table[n]), |
176 | n == 255 ? "\n" : (n % 5 == 4 ? ",\n" : ", ")); | 176 | n == 255 ? "\n" : (n % 5 == 4 ? ",\n" : ", ")); |
177 | } | 177 | } |
178 | #endif /* MAKECRCH */ | 178 | #endif /* MAKECRCH */ |
179 | 179 | ||
180 | #else /* !DYNAMIC_CRC_TABLE */ | 180 | #else /* !DYNAMIC_CRC_TABLE */ |
181 | /* ======================================================================== | 181 | /* ======================================================================== |
182 | * Tables of CRC-32s of all single-byte values, made by make_crc_table(). | 182 | * Tables of CRC-32s of all single-byte values, made by make_crc_table(). |
183 | */ | 183 | */ |
184 | #include "crc32.h" | 184 | #include "crc32.h" |
185 | #endif /* DYNAMIC_CRC_TABLE */ | 185 | #endif /* DYNAMIC_CRC_TABLE */ |
186 | 186 | ||
187 | /* ========================================================================= | 187 | /* ========================================================================= |
188 | * This function can be used by asm versions of crc32() | 188 | * This function can be used by asm versions of crc32() |
189 | */ | 189 | */ |
190 | const z_crc_t FAR * ZEXPORT get_crc_table() | 190 | const z_crc_t FAR * ZEXPORT get_crc_table() |
191 | { | 191 | { |
192 | #ifdef DYNAMIC_CRC_TABLE | 192 | #ifdef DYNAMIC_CRC_TABLE |
193 | if (crc_table_empty) | 193 | if (crc_table_empty) |
194 | make_crc_table(); | 194 | make_crc_table(); |
195 | #endif /* DYNAMIC_CRC_TABLE */ | 195 | #endif /* DYNAMIC_CRC_TABLE */ |
196 | return (const z_crc_t FAR *)crc_table; | 196 | return (const z_crc_t FAR *)crc_table; |
197 | } | 197 | } |
198 | 198 | ||
199 | /* ========================================================================= */ | 199 | /* ========================================================================= */ |
200 | #define DO1 crc = crc_table[0][((int)crc ^ (*buf++)) & 0xff] ^ (crc >> 8) | 200 | #define DO1 crc = crc_table[0][((int)crc ^ (*buf++)) & 0xff] ^ (crc >> 8) |
201 | #define DO8 DO1; DO1; DO1; DO1; DO1; DO1; DO1; DO1 | 201 | #define DO8 DO1; DO1; DO1; DO1; DO1; DO1; DO1; DO1 |
202 | 202 | ||
203 | /* ========================================================================= */ | 203 | /* ========================================================================= */ |
204 | unsigned long ZEXPORT crc32(crc, buf, len) | 204 | unsigned long ZEXPORT crc32(crc, buf, len) |
205 | unsigned long crc; | 205 | unsigned long crc; |
206 | const unsigned char FAR *buf; | 206 | const unsigned char FAR *buf; |
207 | uInt len; | 207 | uInt len; |
208 | { | 208 | { |
209 | if (buf == Z_NULL) return 0UL; | 209 | if (buf == Z_NULL) return 0UL; |
210 | 210 | ||
211 | #ifdef DYNAMIC_CRC_TABLE | 211 | #ifdef DYNAMIC_CRC_TABLE |
212 | if (crc_table_empty) | 212 | if (crc_table_empty) |
213 | make_crc_table(); | 213 | make_crc_table(); |
214 | #endif /* DYNAMIC_CRC_TABLE */ | 214 | #endif /* DYNAMIC_CRC_TABLE */ |
215 | 215 | ||
216 | #ifdef BYFOUR | 216 | #ifdef BYFOUR |
217 | if (sizeof(void *) == sizeof(ptrdiff_t)) { | 217 | if (sizeof(void *) == sizeof(ptrdiff_t)) { |
218 | z_crc_t endian; | 218 | z_crc_t endian; |
219 | 219 | ||
220 | endian = 1; | 220 | endian = 1; |
221 | if (*((unsigned char *)(&endian))) | 221 | if (*((unsigned char *)(&endian))) |
222 | return crc32_little(crc, buf, len); | 222 | return crc32_little(crc, buf, len); |
223 | else | 223 | else |
224 | return crc32_big(crc, buf, len); | 224 | return crc32_big(crc, buf, len); |
225 | } | 225 | } |
226 | #endif /* BYFOUR */ | 226 | #endif /* BYFOUR */ |
227 | crc = crc ^ 0xffffffffUL; | 227 | crc = crc ^ 0xffffffffUL; |
228 | while (len >= 8) { | 228 | while (len >= 8) { |
229 | DO8; | 229 | DO8; |
230 | len -= 8; | 230 | len -= 8; |
231 | } | 231 | } |
232 | if (len) do { | 232 | if (len) do { |
233 | DO1; | 233 | DO1; |
234 | } while (--len); | 234 | } while (--len); |
235 | return crc ^ 0xffffffffUL; | 235 | return crc ^ 0xffffffffUL; |
236 | } | 236 | } |
237 | 237 | ||
238 | #ifdef BYFOUR | 238 | #ifdef BYFOUR |
239 | 239 | ||
240 | /* ========================================================================= */ | 240 | /* ========================================================================= */ |
241 | #define DOLIT4 c ^= *buf4++; \ | 241 | #define DOLIT4 c ^= *buf4++; \ |
242 | c = crc_table[3][c & 0xff] ^ crc_table[2][(c >> 8) & 0xff] ^ \ | 242 | c = crc_table[3][c & 0xff] ^ crc_table[2][(c >> 8) & 0xff] ^ \ |
243 | crc_table[1][(c >> 16) & 0xff] ^ crc_table[0][c >> 24] | 243 | crc_table[1][(c >> 16) & 0xff] ^ crc_table[0][c >> 24] |
244 | #define DOLIT32 DOLIT4; DOLIT4; DOLIT4; DOLIT4; DOLIT4; DOLIT4; DOLIT4; DOLIT4 | 244 | #define DOLIT32 DOLIT4; DOLIT4; DOLIT4; DOLIT4; DOLIT4; DOLIT4; DOLIT4; DOLIT4 |
245 | 245 | ||
246 | /* ========================================================================= */ | 246 | /* ========================================================================= */ |
247 | local unsigned long crc32_little(crc, buf, len) | 247 | local unsigned long crc32_little(crc, buf, len) |
248 | unsigned long crc; | 248 | unsigned long crc; |
249 | const unsigned char FAR *buf; | 249 | const unsigned char FAR *buf; |
250 | unsigned len; | 250 | unsigned len; |
251 | { | 251 | { |
252 | register z_crc_t c; | 252 | register z_crc_t c; |
253 | register const z_crc_t FAR *buf4; | 253 | register const z_crc_t FAR *buf4; |
254 | 254 | ||
255 | c = (z_crc_t)crc; | 255 | c = (z_crc_t)crc; |
256 | c = ~c; | 256 | c = ~c; |
257 | while (len && ((ptrdiff_t)buf & 3)) { | 257 | while (len && ((ptrdiff_t)buf & 3)) { |
258 | c = crc_table[0][(c ^ *buf++) & 0xff] ^ (c >> 8); | 258 | c = crc_table[0][(c ^ *buf++) & 0xff] ^ (c >> 8); |
259 | len--; | 259 | len--; |
260 | } | 260 | } |
261 | 261 | ||
262 | buf4 = (const z_crc_t FAR *)(const void FAR *)buf; | 262 | buf4 = (const z_crc_t FAR *)(const void FAR *)buf; |
263 | while (len >= 32) { | 263 | while (len >= 32) { |
264 | DOLIT32; | 264 | DOLIT32; |
265 | len -= 32; | 265 | len -= 32; |
266 | } | 266 | } |
267 | while (len >= 4) { | 267 | while (len >= 4) { |
268 | DOLIT4; | 268 | DOLIT4; |
269 | len -= 4; | 269 | len -= 4; |
270 | } | 270 | } |
271 | buf = (const unsigned char FAR *)buf4; | 271 | buf = (const unsigned char FAR *)buf4; |
272 | 272 | ||
273 | if (len) do { | 273 | if (len) do { |
274 | c = crc_table[0][(c ^ *buf++) & 0xff] ^ (c >> 8); | 274 | c = crc_table[0][(c ^ *buf++) & 0xff] ^ (c >> 8); |
275 | } while (--len); | 275 | } while (--len); |
276 | c = ~c; | 276 | c = ~c; |
277 | return (unsigned long)c; | 277 | return (unsigned long)c; |
278 | } | 278 | } |
279 | 279 | ||
280 | /* ========================================================================= */ | 280 | /* ========================================================================= */ |
281 | #define DOBIG4 c ^= *++buf4; \ | 281 | #define DOBIG4 c ^= *++buf4; \ |
282 | c = crc_table[4][c & 0xff] ^ crc_table[5][(c >> 8) & 0xff] ^ \ | 282 | c = crc_table[4][c & 0xff] ^ crc_table[5][(c >> 8) & 0xff] ^ \ |
283 | crc_table[6][(c >> 16) & 0xff] ^ crc_table[7][c >> 24] | 283 | crc_table[6][(c >> 16) & 0xff] ^ crc_table[7][c >> 24] |
284 | #define DOBIG32 DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4 | 284 | #define DOBIG32 DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4; DOBIG4 |
285 | 285 | ||
286 | /* ========================================================================= */ | 286 | /* ========================================================================= */ |
287 | local unsigned long crc32_big(crc, buf, len) | 287 | local unsigned long crc32_big(crc, buf, len) |
288 | unsigned long crc; | 288 | unsigned long crc; |
289 | const unsigned char FAR *buf; | 289 | const unsigned char FAR *buf; |
290 | unsigned len; | 290 | unsigned len; |
291 | { | 291 | { |
292 | register z_crc_t c; | 292 | register z_crc_t c; |
293 | register const z_crc_t FAR *buf4; | 293 | register const z_crc_t FAR *buf4; |
294 | 294 | ||
295 | c = ZSWAP32((z_crc_t)crc); | 295 | c = ZSWAP32((z_crc_t)crc); |
296 | c = ~c; | 296 | c = ~c; |
297 | while (len && ((ptrdiff_t)buf & 3)) { | 297 | while (len && ((ptrdiff_t)buf & 3)) { |
298 | c = crc_table[4][(c >> 24) ^ *buf++] ^ (c << 8); | 298 | c = crc_table[4][(c >> 24) ^ *buf++] ^ (c << 8); |
299 | len--; | 299 | len--; |
300 | } | 300 | } |
301 | 301 | ||
302 | buf4 = (const z_crc_t FAR *)(const void FAR *)buf; | 302 | buf4 = (const z_crc_t FAR *)(const void FAR *)buf; |
303 | buf4--; | 303 | buf4--; |
304 | while (len >= 32) { | 304 | while (len >= 32) { |
305 | DOBIG32; | 305 | DOBIG32; |
306 | len -= 32; | 306 | len -= 32; |
307 | } | 307 | } |
308 | while (len >= 4) { | 308 | while (len >= 4) { |
309 | DOBIG4; | 309 | DOBIG4; |
310 | len -= 4; | 310 | len -= 4; |
311 | } | 311 | } |
312 | buf4++; | 312 | buf4++; |
313 | buf = (const unsigned char FAR *)buf4; | 313 | buf = (const unsigned char FAR *)buf4; |
314 | 314 | ||
315 | if (len) do { | 315 | if (len) do { |
316 | c = crc_table[4][(c >> 24) ^ *buf++] ^ (c << 8); | 316 | c = crc_table[4][(c >> 24) ^ *buf++] ^ (c << 8); |
317 | } while (--len); | 317 | } while (--len); |
318 | c = ~c; | 318 | c = ~c; |
319 | return (unsigned long)(ZSWAP32(c)); | 319 | return (unsigned long)(ZSWAP32(c)); |
320 | } | 320 | } |
321 | 321 | ||
322 | #endif /* BYFOUR */ | 322 | #endif /* BYFOUR */ |
323 | 323 | ||
324 | #define GF2_DIM 32 /* dimension of GF(2) vectors (length of CRC) */ | 324 | #define GF2_DIM 32 /* dimension of GF(2) vectors (length of CRC) */ |
325 | 325 | ||
326 | /* ========================================================================= */ | 326 | /* ========================================================================= */ |
327 | local unsigned long gf2_matrix_times(mat, vec) | 327 | local unsigned long gf2_matrix_times(mat, vec) |
328 | unsigned long *mat; | 328 | unsigned long *mat; |
329 | unsigned long vec; | 329 | unsigned long vec; |
330 | { | 330 | { |
331 | unsigned long sum; | 331 | unsigned long sum; |
332 | 332 | ||
333 | sum = 0; | 333 | sum = 0; |
334 | while (vec) { | 334 | while (vec) { |
335 | if (vec & 1) | 335 | if (vec & 1) |
336 | sum ^= *mat; | 336 | sum ^= *mat; |
337 | vec >>= 1; | 337 | vec >>= 1; |
338 | mat++; | 338 | mat++; |
339 | } | 339 | } |
340 | return sum; | 340 | return sum; |
341 | } | 341 | } |
342 | 342 | ||
343 | /* ========================================================================= */ | 343 | /* ========================================================================= */ |
344 | local void gf2_matrix_square(square, mat) | 344 | local void gf2_matrix_square(square, mat) |
345 | unsigned long *square; | 345 | unsigned long *square; |
346 | unsigned long *mat; | 346 | unsigned long *mat; |
347 | { | 347 | { |
348 | int n; | 348 | int n; |
349 | 349 | ||
350 | for (n = 0; n < GF2_DIM; n++) | 350 | for (n = 0; n < GF2_DIM; n++) |
351 | square[n] = gf2_matrix_times(mat, mat[n]); | 351 | square[n] = gf2_matrix_times(mat, mat[n]); |
352 | } | 352 | } |
353 | 353 | ||
354 | /* ========================================================================= */ | 354 | /* ========================================================================= */ |
355 | local uLong crc32_combine_(crc1, crc2, len2) | 355 | local uLong crc32_combine_(crc1, crc2, len2) |
356 | uLong crc1; | 356 | uLong crc1; |
357 | uLong crc2; | 357 | uLong crc2; |
358 | z_off64_t len2; | 358 | z_off64_t len2; |
359 | { | 359 | { |
360 | int n; | 360 | int n; |
361 | unsigned long row; | 361 | unsigned long row; |
362 | unsigned long even[GF2_DIM]; /* even-power-of-two zeros operator */ | 362 | unsigned long even[GF2_DIM]; /* even-power-of-two zeros operator */ |
363 | unsigned long odd[GF2_DIM]; /* odd-power-of-two zeros operator */ | 363 | unsigned long odd[GF2_DIM]; /* odd-power-of-two zeros operator */ |
364 | 364 | ||
365 | /* degenerate case (also disallow negative lengths) */ | 365 | /* degenerate case (also disallow negative lengths) */ |
366 | if (len2 <= 0) | 366 | if (len2 <= 0) |
367 | return crc1; | 367 | return crc1; |
368 | 368 | ||
369 | /* put operator for one zero bit in odd */ | 369 | /* put operator for one zero bit in odd */ |
370 | odd[0] = 0xedb88320UL; /* CRC-32 polynomial */ | 370 | odd[0] = 0xedb88320UL; /* CRC-32 polynomial */ |
371 | row = 1; | 371 | row = 1; |
372 | for (n = 1; n < GF2_DIM; n++) { | 372 | for (n = 1; n < GF2_DIM; n++) { |
373 | odd[n] = row; | 373 | odd[n] = row; |
374 | row <<= 1; | 374 | row <<= 1; |
375 | } | 375 | } |
376 | 376 | ||
377 | /* put operator for two zero bits in even */ | 377 | /* put operator for two zero bits in even */ |
378 | gf2_matrix_square(even, odd); | 378 | gf2_matrix_square(even, odd); |
379 | 379 | ||
380 | /* put operator for four zero bits in odd */ | 380 | /* put operator for four zero bits in odd */ |
381 | gf2_matrix_square(odd, even); | 381 | gf2_matrix_square(odd, even); |
382 | 382 | ||
383 | /* apply len2 zeros to crc1 (first square will put the operator for one | 383 | /* apply len2 zeros to crc1 (first square will put the operator for one |
384 | zero byte, eight zero bits, in even) */ | 384 | zero byte, eight zero bits, in even) */ |
385 | do { | 385 | do { |
386 | /* apply zeros operator for this bit of len2 */ | 386 | /* apply zeros operator for this bit of len2 */ |
387 | gf2_matrix_square(even, odd); | 387 | gf2_matrix_square(even, odd); |
388 | if (len2 & 1) | 388 | if (len2 & 1) |
389 | crc1 = gf2_matrix_times(even, crc1); | 389 | crc1 = gf2_matrix_times(even, crc1); |
390 | len2 >>= 1; | 390 | len2 >>= 1; |
391 | 391 | ||
392 | /* if no more bits set, then done */ | 392 | /* if no more bits set, then done */ |
393 | if (len2 == 0) | 393 | if (len2 == 0) |
394 | break; | 394 | break; |
395 | 395 | ||
396 | /* another iteration of the loop with odd and even swapped */ | 396 | /* another iteration of the loop with odd and even swapped */ |
397 | gf2_matrix_square(odd, even); | 397 | gf2_matrix_square(odd, even); |
398 | if (len2 & 1) | 398 | if (len2 & 1) |
399 | crc1 = gf2_matrix_times(odd, crc1); | 399 | crc1 = gf2_matrix_times(odd, crc1); |
400 | len2 >>= 1; | 400 | len2 >>= 1; |
401 | 401 | ||
402 | /* if no more bits set, then done */ | 402 | /* if no more bits set, then done */ |
403 | } while (len2 != 0); | 403 | } while (len2 != 0); |
404 | 404 | ||
405 | /* return combined crc */ | 405 | /* return combined crc */ |
406 | crc1 ^= crc2; | 406 | crc1 ^= crc2; |
407 | return crc1; | 407 | return crc1; |
408 | } | 408 | } |
409 | 409 | ||
410 | /* ========================================================================= */ | 410 | /* ========================================================================= */ |
411 | uLong ZEXPORT crc32_combine(crc1, crc2, len2) | 411 | uLong ZEXPORT crc32_combine(crc1, crc2, len2) |
412 | uLong crc1; | 412 | uLong crc1; |
413 | uLong crc2; | 413 | uLong crc2; |
414 | z_off_t len2; | 414 | z_off_t len2; |
415 | { | 415 | { |
416 | return crc32_combine_(crc1, crc2, len2); | 416 | return crc32_combine_(crc1, crc2, len2); |
417 | } | 417 | } |
418 | 418 | ||
419 | uLong ZEXPORT crc32_combine64(crc1, crc2, len2) | 419 | uLong ZEXPORT crc32_combine64(crc1, crc2, len2) |
420 | uLong crc1; | 420 | uLong crc1; |
421 | uLong crc2; | 421 | uLong crc2; |
422 | z_off64_t len2; | 422 | z_off64_t len2; |
423 | { | 423 | { |
424 | return crc32_combine_(crc1, crc2, len2); | 424 | return crc32_combine_(crc1, crc2, len2); |
425 | } | 425 | } |