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authorIgor Pashev <pashev.igor@gmail.com>2012-12-31 05:04:42 +0400
committerIgor Pashev <pashev.igor@gmail.com>2012-12-31 05:04:42 +0400
commit71dc8760ff4de5f365330d1bc571d934deb54af9 (patch)
tree7346d42a282562a3937d82307012b5857d642ce6 /wodim/crc16.c
downloadcdrkit-upstream.tar.gz
Imported Upstream version 1.1.11upstream/1.1.11upstream
Diffstat (limited to 'wodim/crc16.c')
-rw-r--r--wodim/crc16.c160
1 files changed, 160 insertions, 0 deletions
diff --git a/wodim/crc16.c b/wodim/crc16.c
new file mode 100644
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+++ b/wodim/crc16.c
@@ -0,0 +1,160 @@
+/*
+ * This file has been modified for the cdrkit suite.
+ *
+ * The behaviour and appearence of the program code below can differ to a major
+ * extent from the version distributed by the original author(s).
+ *
+ * For details, see Changelog file distributed with the cdrkit package. If you
+ * received this file from another source then ask the distributing person for
+ * a log of modifications.
+ *
+ */
+
+/* @(#)crc16.c 1.6 04/03/02 Copyright 1998-2004 J. Schilling */
+/*
+ * Q-subchannel CRC subroutines
+ *
+ * Polynom is: p(x) = x ** 16 + x ** 12 + x ** 5 + 1
+ * If computed over 12 bytes, the result must be zero.
+ * On the disk the CRC bits are inverted.
+ *
+ * Copyright (c) 1998-2003 J. Schilling
+ */
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; see the file COPYING. If not, write to the Free Software
+ * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <mconfig.h>
+#include <standard.h>
+#include <utypes.h>
+#include "crc16.h"
+
+static UInt16_t updcrc(Uint p_crc, UInt8_t *cp, Uint cnt);
+UInt16_t calcCRC(Uchar *buf, Uint bsize);
+UInt16_t fillcrc(Uchar *buf, Uint bsize);
+UInt16_t flip_crc_error_corr(Uchar *b, Uint bsize, Uint p_crc);
+
+
+ /* number of bits in CRC: don't change it. */
+#define BPW 16
+
+ /* this the number of bits per char: don't change it. */
+#define BPB 8
+
+static UInt16_t crctab[1<<BPB] = {
+ 0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
+ 0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
+ 0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
+ 0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
+ 0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485,
+ 0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
+ 0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4,
+ 0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
+ 0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823,
+ 0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
+ 0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12,
+ 0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
+ 0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41,
+ 0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
+ 0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70,
+ 0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
+ 0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f,
+ 0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
+ 0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e,
+ 0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
+ 0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
+ 0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
+ 0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c,
+ 0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
+ 0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab,
+ 0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3,
+ 0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
+ 0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92,
+ 0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9,
+ 0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1,
+ 0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8,
+ 0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0,
+};
+
+#define SUBSIZE 96 /* 12 bytes with 8 bits */
+
+static UInt16_t
+updcrc(Uint p_crc, register UInt8_t *cp, register Uint cnt)
+{
+ register UInt16_t crc = p_crc;
+
+ while (cnt-- > 0) {
+ crc = (crc<<BPB) ^ crctab[(crc>>(BPW-BPB)) ^ (*cp++)];
+ }
+ return (crc);
+}
+
+/*static UInt16_t*/
+UInt16_t
+calcCRC(Uchar *buf, Uint bsize)
+{
+ return (updcrc(0x0000, (UInt8_t *)buf, bsize));
+}
+
+/*
+ * CRC für Q-Sub füllen
+ */
+UInt16_t
+fillcrc(Uchar *buf, Uint bsize)
+{
+ UInt16_t crc = calcCRC(buf, bsize-2);
+
+ /*
+ * Invert CRC bits for RED Book compliance.
+ */
+ crc = crc ^ 0xFFFF;
+
+ buf[bsize-2] = (crc >> 8) & 0xFF;
+ buf[bsize-1] = crc & 0xFF;
+ return (crc);
+}
+
+static UInt8_t fliptab[BPB] = {
+ 0x01,
+ 0x02,
+ 0x04,
+ 0x08,
+ 0x10,
+ 0x20,
+ 0x40,
+ 0x80,
+};
+
+UInt16_t
+flip_crc_error_corr(Uchar *b, Uint bsize, Uint p_crc)
+{
+ register UInt16_t crc = p_crc;
+ register Uint btsize = bsize * BPB;
+
+ if (crc != 0) {
+ int i;
+
+ for (i = 0; i < btsize; i++) {
+ UInt8_t c;
+
+ c = fliptab[i % BPB];
+ b[i / BPB] ^= c;
+ if ((crc = calcCRC(b, bsize)) == 0) {
+ return (crc);
+ }
+ b[i / BPB] ^= c;
+ }
+ }
+ return (crc & 0xffff);
+}