![[BACK]](/icons/cvsweb/back.gif){kind=icon}
Return to aitcrc.c CVS log ![[TXT]](/icons/cvsweb/text.gif){kind=icon}
![[DIR]](/icons/cvsweb/dir.gif){kind=icon}
Up to [ELWIX - Embedded LightWeight unIX -] / libaitcrc / src|
Return to aitcrc.c CVS log | Up to [ELWIX - Embedded LightWeight unIX -] / libaitcrc / src |
1.1 misho 1: /*************************************************************************
2: * (C) 2008 AITNET ltd - Sofia/Bulgaria - <misho@aitbg.com>
3: * by Michael Pounov <misho@openbsd-bg.org>
4: *
5: * $Author: misho $
6: * $Id: global.h,v 1.1.1.1.2.2 2008/09/30 20:00:26 misho Exp $
7: *
8: *************************************************************************/
9: #include "global.h"
10:
11:
12: static int crc_Errno;
13: static char crc_Error[MAX_STR + 1];
14:
15: const u_long crc_modAdler = 0xFFF1L;
16:
17: const crcPoly_t crc_Poly[] = {
18: { 1, (u_long) 0x1, "CRC-1-Parity" },
19: { 4, (u_long) 0x3, "CRC-4-ITU" },
20: { 5, (u_long) 0x15, "CRC-5-ITU" },
21: { 6, (u_long) 0x3, "CRC-6-ITU" },
22: { 7, (u_long) 0x9, "CRC-7-MMC" },
23: { 8, (u_long) 0x8D, "CRC-8-CCITT" },
24: { 10, (u_long) 0x233, "CRC-10" },
25: { 11, (u_long) 0x385, "CRC-11-FlexRay" },
26: { 12, (u_long) 0x80F, "CRC-12-Telco" },
27: { 15, (u_long) 0x4599, "CRC-15-CAN" },
28: { 16, (u_long) 0x8005, "CRC-16-IBM" },
29: { 24, (u_long) 0x864CFB, "CRC-24-Radix64" },
30: { 30, (u_long) 0x2030B9C7, "CRC-30-CDMA" },
31: { 32, (u_long) 0x04C11DB7, "CRC-32-802.3" }
32: };
33:
34: // ----------------------------------------------------------
35:
36: inline int crc_GetErrno()
37: {
38: return crc_Errno;
39: }
40:
41: inline const char *crc_GetError()
42: {
43: return crc_Error;
44: }
45:
46: // ----------------------------------------------------------
47:
48: inline u_long crcReflect(u_long crcNum, u_char crcBits)
49: {
50: register u_long i, j, rev;
51:
52: for (i = (u_long) 1 << (crcBits - 1), j = 1, rev ^= rev; i; i >>= 1, j <<= 1)
53: if (crcNum & i)
54: rev |= j;
55:
56: crc_Errno ^= crc_Errno;
57: return rev;
58: }
59:
60: inline u_long crcCalc(u_char * __restrict psBuf, u_int bufLen, u_char crcBits, u_char RevOpts, u_long initCRC, u_long xorCRC)
61: {
62: const u_long bits = sizeof(long) * 8 - crcBits;
63: u_long poly, crchibit, crc;
64: register u_long i, j, b, ch;
65:
66: if (!psBuf) {
67: crc_Errno = 1;
68: strlcpy(crc_Error, "crcCalc(): Invalid parameters!", MAX_STR + 1);
69: return -1;
70: }
71:
72: switch (crcBits) {
73: case 1:
74: poly = crc_Poly[0].poly_num;
75: break;
76: case 4:
77: poly = crc_Poly[1].poly_num;
78: break;
79: case 5:
80: poly = crc_Poly[2].poly_num;
81: break;
82: case 6:
83: poly = crc_Poly[3].poly_num;
84: break;
85: case 7:
86: poly = crc_Poly[4].poly_num;
87: break;
88: case 8:
89: poly = crc_Poly[5].poly_num;
90: break;
91: case 10:
92: poly = crc_Poly[6].poly_num;
93: break;
94: case 11:
95: poly = crc_Poly[7].poly_num;
96: break;
97: case 12:
98: poly = crc_Poly[8].poly_num;
99: break;
100: case 15:
101: poly = crc_Poly[9].poly_num;
102: break;
103: case 16:
104: poly = crc_Poly[10].poly_num;
105: break;
106: case 24:
107: poly = crc_Poly[11].poly_num;
108: break;
109: case 30:
110: poly = crc_Poly[12].poly_num;
111: break;
112: case 32:
113: poly = crc_Poly[13].poly_num;
114: break;
115: default:
116: crc_Errno = 2;
117: strlcpy(crc_Error, "crcCalc(): Unsupported CRC method!!!", MAX_STR + 1);
118: return -1;
119: }
120: poly <<= bits;
121:
122: crchibit = (u_long) 1 << (crcBits - 1);
123: crchibit <<= bits;
124: crc = initCRC << bits;
125:
126: for (i = 0; i < bufLen; i++) {
127: ch = (u_long) *psBuf++;
128: if (RevOpts & REVOPTS_REVERTBYTE)
129: ch = crcReflect(ch, 8);
130:
131: for (j = 0x80; j; j >>= 1) {
132: b = crc & crchibit;
133: crc <<= 1;
134:
135: if (ch & j)
136: b ^= crchibit;
137: if (b)
138: crc ^= poly;
139: }
140: }
141:
142: if (RevOpts & REVOPTS_REVERTCRC)
143: crc = crcReflect(crc, sizeof(long) * 8);
144: crc ^= xorCRC << bits;
145: crc &= (((crchibit - 1) << 1) | 1);
146: if (!(RevOpts & REVOPTS_REVERTCRC))
147: crc >>= bits;
148:
149: crc_Errno ^= crc_Errno;
150: return crc;
151: }
152:
153: // ----------------------------------------------------------
154:
155: inline u_short crcIP(u_short * __restrict nBuf, int bufLen)
156: {
157: register u_long sum;
158:
159: if (!nBuf) {
160: crc_Errno = 1;
161: strlcpy(crc_Error, "crcIP(): Invalid parameters!", MAX_STR + 1);
162: return -1;
163: }
164:
165: for (sum = 0; bufLen; bufLen--)
166: sum += *nBuf++;
167:
168: sum = (sum >> 16) + (sum & 0xFFFF);
169: sum += sum >> 16;
170:
171: crc_Errno ^= crc_Errno;
172: return (u_short) ~sum;
173: }
174:
175: inline u_long crcFletcher(u_short * __restrict nBuf, int bufLen)
176: {
177: register u_long s1, s2, clen;
178:
179: if (!nBuf) {
180: crc_Errno = 1;
181: strlcpy(crc_Error, "crcFletcher(): Invalid parameters!", MAX_STR + 1);
182: return -1;
183: }
184:
185: s1 = s2 = 0xFFFF;
186: while (bufLen) {
187: clen = bufLen > MAX_FLETCHER_DIGEST ? MAX_FLETCHER_DIGEST : bufLen;
188: bufLen -= clen;
189:
190: do {
191: s1 += (u_long) *nBuf++;
192: s2 += s1;
193: } while (--clen);
194:
195: s1 = (s1 >> 16) + (s1 & 0xFFFF);
196: s2 = (s2 >> 16) + (s2 & 0xFFFF);
197: }
198:
199: crc_Errno ^= crc_Errno;
200: return (s2 << 16) | s1;
201: }
202:
203: inline u_long crcAdler(u_char * __restrict psBuf, int bufLen)
204: {
205: register u_long s1, s2, clen;
206:
207: if (!psBuf) {
208: crc_Errno = 1;
209: strlcpy(crc_Error, "crcAdler(): Invalid parameters!", MAX_STR + 1);
210: return -1;
211: }
212:
213: s1 = 1L;
214: s2 ^= s2;
215: while (bufLen) {
216: clen = bufLen > MAX_ADLER_DIGEST ? MAX_ADLER_DIGEST : bufLen;
217: bufLen -= clen;
218:
219: do {
220: s1 += (u_long) *psBuf++;
221: s2 += s1;
222: } while (--clen);
223:
224: s1 %= crc_modAdler;
225: s2 %= crc_modAdler;
226: }
227:
228: crc_Errno ^= crc_Errno;
229: return (s2 << 16) | s1;
230: }