Add a symlink option to the patching script

[yaffs2.git] / yaffs_ecc.c

diff --git a/yaffs_ecc.c b/yaffs_ecc.c
index 59f3ed9cd118cffb98371b827605f282ac79b40a..be860d01a6f3853695efb2a9184bb43ffe728927 100644 (file)
--- a/yaffs_ecc.c
+++ b/yaffs_ecc.c
@@ -1,27 +1,25 @@
 /*
- * YAFFS: Yet another FFS. A NAND-flash specific file system. 
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
  *
- * yaffs_ecc.c: ECC generation/correction algorithms.
- *
- * Copyright (C) 2002 Aleph One Ltd.
+ * Copyright (C) 2002-2007 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
  *
  * Created by Charles Manning <charles@aleph1.co.uk>
  *
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public License
- * version 2.1 as published by the Free Software Foundation.
+ * 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 code implements the ECC algorithm used in SmartMedia.
-  *
-  * The ECC comprises 22 bits of parity information and is stuffed into 3 bytes. 
-  * The two unused bit are set to 1.
-  * The ECC can correct single bit errors in a 256-byte page of data. Thus, two such ECC 
-  * blocks are used on a 512-byte NAND page.
-  *
-  */
+/*
+ * This code implements the ECC algorithm used in SmartMedia.
+ *
+ * The ECC comprises 22 bits of parity information and is stuffed into 3 bytes. 
+ * The two unused bit are set to 1.
+ * The ECC can correct single bit errors in a 256-byte page of data. Thus, two such ECC 
+ * blocks are used on a 512-byte NAND page.
+ *
+ */
 
 /* Table generated by gen-ecc.c
  * Using a table means we do not have to calculate p1..p4 and p1'..p4'
@@ -31,7 +29,7 @@
  */
 
 const char *yaffs_ecc_c_version =
-    "$Id: yaffs_ecc.c,v 1.6 2005-08-11 02:51:49 charles Exp $";
+    "$Id: yaffs_ecc.c,v 1.9 2007-02-14 01:09:06 wookey Exp $";
 
 #include "yportenv.h"
 
@@ -295,7 +293,8 @@ int yaffs_ECCCorrectOther(unsigned char *data, unsigned nBytes,
        if ((cDelta | lDelta | lDeltaPrime) == 0)
                return 0; /* no error */
 
-       if (lDelta == ~lDeltaPrime && (((cDelta ^ (cDelta >> 1)) & 0x15) == 0x15))
+       if (lDelta == ~lDeltaPrime && 
+           (((cDelta ^ (cDelta >> 1)) & 0x15) == 0x15))
        {
                /* Single bit (recoverable) error in data */
 
@@ -308,6 +307,9 @@ int yaffs_ECCCorrectOther(unsigned char *data, unsigned nBytes,
                if (cDelta & 0x02)
                        bit |= 0x01;
 
+               if(lDelta >= nBytes)
+                       return -1;
+                       
                data[lDelta] ^= (1 << bit);
 
                return 1; /* corrected */