1 /*
2  * Copyright (c) 2010, Wei Mingzhi <whistler_wmz@users.sf.net>.
3  * All Rights Reserved.
4  *
5  * Based on: Cdrom for Psemu Pro like Emulators
6  * By: linuzappz <linuzappz@hotmail.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, see <http://www.gnu.org/licenses>.
20  */
21 
22 #include "cdr.h"
23 
msf_to_lba(char m,char s,char f)24 unsigned int msf_to_lba(char m, char s, char f) {
25 	return (m * CD_SECS + s) * CD_FRAMES + f - CD_MSF_OFFSET;
26 }
27 
lba_to_msf(unsigned int s,unsigned char * msf)28 void lba_to_msf(unsigned int s, unsigned char *msf) {
29 	s += CD_MSF_OFFSET;
30 
31 	msf[0] = s / CD_FRAMES / CD_SECS;
32 	s = s - msf[0] * CD_FRAMES * CD_SECS;
33 	msf[1] = s / CD_FRAMES;
34 	s = s - msf[1] * CD_FRAMES;
35 	msf[2] = s;
36 }
37 
DecodeRawSubData(unsigned char * subbuffer)38 void DecodeRawSubData(unsigned char *subbuffer) {
39 	unsigned char subQData[12];
40 	int i;
41 
42 	memset(subQData, 0, sizeof(subQData));
43 
44 	for (i = 0; i < 8 * 12; i++) {
45 		if (subbuffer[i] & (1 << 6)) { // only subchannel Q is needed
46 			subQData[i >> 3] |= (1 << (7 - (i & 7)));
47 		}
48 	}
49 
50 	memcpy(&subbuffer[12], subQData, 12);
51 }
52 
53 // lookup table for crc calculation
54 static unsigned short crctab[256] = {
55 	0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50A5, 0x60C6, 0x70E7, 0x8108,
56 	0x9129, 0xA14A, 0xB16B, 0xC18C, 0xD1AD, 0xE1CE, 0xF1EF, 0x1231, 0x0210,
57 	0x3273, 0x2252, 0x52B5, 0x4294, 0x72F7, 0x62D6, 0x9339, 0x8318, 0xB37B,
58 	0xA35A, 0xD3BD, 0xC39C, 0xF3FF, 0xE3DE, 0x2462, 0x3443, 0x0420, 0x1401,
59 	0x64E6, 0x74C7, 0x44A4, 0x5485, 0xA56A, 0xB54B, 0x8528, 0x9509, 0xE5EE,
60 	0xF5CF, 0xC5AC, 0xD58D, 0x3653, 0x2672, 0x1611, 0x0630, 0x76D7, 0x66F6,
61 	0x5695, 0x46B4, 0xB75B, 0xA77A, 0x9719, 0x8738, 0xF7DF, 0xE7FE, 0xD79D,
62 	0xC7BC, 0x48C4, 0x58E5, 0x6886, 0x78A7, 0x0840, 0x1861, 0x2802, 0x3823,
63 	0xC9CC, 0xD9ED, 0xE98E, 0xF9AF, 0x8948, 0x9969, 0xA90A, 0xB92B, 0x5AF5,
64 	0x4AD4, 0x7AB7, 0x6A96, 0x1A71, 0x0A50, 0x3A33, 0x2A12, 0xDBFD, 0xCBDC,
65 	0xFBBF, 0xEB9E, 0x9B79, 0x8B58, 0xBB3B, 0xAB1A, 0x6CA6, 0x7C87, 0x4CE4,
66 	0x5CC5, 0x2C22, 0x3C03, 0x0C60, 0x1C41, 0xEDAE, 0xFD8F, 0xCDEC, 0xDDCD,
67 	0xAD2A, 0xBD0B, 0x8D68, 0x9D49, 0x7E97, 0x6EB6, 0x5ED5, 0x4EF4, 0x3E13,
68 	0x2E32, 0x1E51, 0x0E70, 0xFF9F, 0xEFBE, 0xDFDD, 0xCFFC, 0xBF1B, 0xAF3A,
69 	0x9F59, 0x8F78, 0x9188, 0x81A9, 0xB1CA, 0xA1EB, 0xD10C, 0xC12D, 0xF14E,
70 	0xE16F, 0x1080, 0x00A1, 0x30C2, 0x20E3, 0x5004, 0x4025, 0x7046, 0x6067,
71 	0x83B9, 0x9398, 0xA3FB, 0xB3DA, 0xC33D, 0xD31C, 0xE37F, 0xF35E, 0x02B1,
72 	0x1290, 0x22F3, 0x32D2, 0x4235, 0x5214, 0x6277, 0x7256, 0xB5EA, 0xA5CB,
73 	0x95A8, 0x8589, 0xF56E, 0xE54F, 0xD52C, 0xC50D, 0x34E2, 0x24C3, 0x14A0,
74 	0x0481, 0x7466, 0x6447, 0x5424, 0x4405, 0xA7DB, 0xB7FA, 0x8799, 0x97B8,
75 	0xE75F, 0xF77E, 0xC71D, 0xD73C, 0x26D3, 0x36F2, 0x0691, 0x16B0, 0x6657,
76 	0x7676, 0x4615, 0x5634, 0xD94C, 0xC96D, 0xF90E, 0xE92F, 0x99C8, 0x89E9,
77 	0xB98A, 0xA9AB, 0x5844, 0x4865, 0x7806, 0x6827, 0x18C0, 0x08E1, 0x3882,
78 	0x28A3, 0xCB7D, 0xDB5C, 0xEB3F, 0xFB1E, 0x8BF9, 0x9BD8, 0xABBB, 0xBB9A,
79 	0x4A75, 0x5A54, 0x6A37, 0x7A16, 0x0AF1, 0x1AD0, 0x2AB3, 0x3A92, 0xFD2E,
80 	0xED0F, 0xDD6C, 0xCD4D, 0xBDAA, 0xAD8B, 0x9DE8, 0x8DC9, 0x7C26, 0x6C07,
81 	0x5C64, 0x4C45, 0x3CA2, 0x2C83, 0x1CE0, 0x0CC1, 0xEF1F, 0xFF3E, 0xCF5D,
82 	0xDF7C, 0xAF9B, 0xBFBA, 0x8FD9, 0x9FF8, 0x6E17, 0x7E36, 0x4E55, 0x5E74,
83 	0x2E93, 0x3EB2, 0x0ED1, 0x1EF0
84 };
85 
calcCrc(unsigned char * d,int len)86 unsigned short calcCrc(unsigned char *d, int len) {
87 	unsigned short crc = 0;
88 	int i;
89 
90 	for (i = 0; i < len; i++) {
91 		crc = crctab[(crc >> 8) ^ d[i]] ^ (crc << 8);
92 	}
93 
94 	return ~crc;
95 }
96