patch-1.3.72 linux/drivers/char/ftape/ecc.h

• Lines: 86
• Date: Wed Mar 6 15:07:19 1996
• Orig file: v1.3.71/linux/drivers/char/ftape/ecc.h
• Orig date: Thu Jan 1 02:00:00 1970

diff -u --recursive --new-file v1.3.71/linux/drivers/char/ftape/ecc.h linux/drivers/char/ftape/ecc.h
@@ -0,0 +1,85 @@
+/*
+ *      Copyright (C) 1993 Ning and David Mosberger.
+ *      Original:
+ *      Copyright (C) 1993 Bas Laarhoven.
+ *      Copyright (C) 1992 David L. Brown, Jr.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2, or (at
+ * your option) any later version.
+ *
+ * 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, 675 Mass Ave, Cambridge, MA 02139,
+ * USA.
+ *
+ *
+ * $Source: /home/bas/distr/ftape-2.03b/RCS/ecc.h,v $
+ * $Author: bas $
+ *
+ * $Revision: 1.20 $
+ * $Date: 1995/01/08 14:16:21 $
+ * $State: Beta $
+ *
+ *      This file contains the definitions for the
+ *      Reed-Solomon error correction code 
+ *      for the QIC-40/80 tape streamer device driver.
+ */
+#ifndef _ecc_h_
+#define _ecc_h_
+
+typedef unsigned long BAD_SECTOR;
+#define BAD_CLEAR(entry) ((entry)=0)
+#define BAD_SET(entry,sector) ((entry)|=(1<<(sector)))
+#define BAD_CHECK(entry,sector) ((entry)&(1<<(sector)))
+
+/*
+ * Return values for ecc_correct_data:
+ */
+enum {
+	ECC_OK,			/* Data was correct. */
+	ECC_CORRECTED,		/* Correctable error in data. */
+	ECC_FAILED,		/* Could not correct data. */
+};
+
+/*
+ * Representation of an in memory segment.  MARKED_BAD lists the
+ * sectors that were marked bad during formatting.  If the N-th sector
+ * in a segment is marked bad, bit 1<<N will be set in MARKED_BAD.
+ * The sectors should be read in from the disk and packed, as if the
+ * bad sectors were not there, and the segment just contained fewer
+ * sectors.  READ_SECTORS is a bitmap of errors encountered while
+ * reading the data.  These offsets are relative to the packed data.
+ * BLOCKS is a count of the sectors not marked bad.  This is just to
+ * prevent having to count the zero bits in MARKED_BAD each time this
+ * is needed.  DATA is the actual sector packed data from (or to) the
+ * tape.
+ */
+struct memory_segment {
+	BAD_SECTOR marked_bad;
+	BAD_SECTOR read_bad;
+	int blocks;
+	unsigned char *data;
+	BAD_SECTOR corrected;
+};
+
+/*
+ * ecc.c defined global variables:
+ */
+#ifdef TEST
+extern int ftape_ecc_tracing;
+#endif
+
+/*
+ * ecc.c defined global functions:
+ */
+extern int ecc_correct_data(struct memory_segment *data);
+extern int ecc_set_segment_parity(struct memory_segment *data);
+
+#endif	/* _ecc_h_ */