X-Git-Url: http://www.aleph1.co.uk/gitweb/?p=yaffs2.git;a=blobdiff_plain;f=yaffs_checkptrw.c;h=2f3f875f75a65e677c6ee24688a3804550746077;hp=c61eaa3db88926e3a1e178d576d42ffbed3a0ba9;hb=b7513bb1b6b84d430d1f1af6ccf2cefe8c2c5ce0;hpb=03f993b7061828ebced8874ca88b06e5354bb325

diff --git a/yaffs_checkptrw.c b/yaffs_checkptrw.c
index c61eaa3..2f3f875 100644
--- a/yaffs_checkptrw.c
+++ b/yaffs_checkptrw.c
@@ -1,6 +1,7 @@
-/* YAFFS: Yet another FFS. A NAND-flash specific file system. 
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
  *
- * 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>
@@ -8,11 +9,10 @@
  * 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.
- *
  */
 
 const char *yaffs_checkptrw_c_version =
-    "$Id: yaffs_checkptrw.c,v 1.11 2006-11-11 23:27:04 charles Exp $";
+    "$Id: yaffs_checkptrw.c,v 1.14 2007-05-15 20:07:40 charles Exp $";
 
 
 #include "yaffs_checkptrw.h"
@@ -32,7 +32,6 @@ static int yaffs_CheckpointSpaceOk(yaffs_Device *dev)
 }
 
 
-
 static int yaffs_CheckpointErase(yaffs_Device *dev)
 {
 	
@@ -153,6 +152,8 @@ int yaffs_CheckpointOpen(yaffs_Device *dev, int forWriting)
 	dev->checkpointOpenForWrite = forWriting;
 	
 	dev->checkpointByteCount = 0;
+	dev->checkpointSum = 0;
+	dev->checkpointXor = 0;
 	dev->checkpointCurrentBlock = -1;
 	dev->checkpointCurrentChunk = -1;
 	dev->checkpointNextBlock = dev->internalStartBlock;
@@ -180,6 +181,14 @@ int yaffs_CheckpointOpen(yaffs_Device *dev, int forWriting)
 	return 1;
 }
 
+int yaffs_GetCheckpointSum(yaffs_Device *dev, __u32 *sum)
+{
+	__u32 compositeSum;
+	compositeSum =  (dev->checkpointSum << 8) | (dev->checkpointXor & 0xFF);
+	*sum = compositeSum;
+	return 1;
+}
+
 static int yaffs_CheckpointFlushBuffer(yaffs_Device *dev)
 {
 
@@ -243,12 +252,18 @@ int yaffs_CheckpointWrite(yaffs_Device *dev,const void *data, int nBytes)
 
 	if(!dev->checkpointBuffer)
 		return 0;
+		
+	if(!dev->checkpointOpenForWrite)
+		return -1;
 
 	while(i < nBytes && ok) {
 		
 
 		
-		 dev->checkpointBuffer[dev->checkpointByteOffset] = *dataBytes ;
+		dev->checkpointBuffer[dev->checkpointByteOffset] = *dataBytes ;
+		dev->checkpointSum += *dataBytes;
+		dev->checkpointXor ^= *dataBytes;
+		 
 		dev->checkpointByteOffset++;
 		i++;
 		dataBytes++;
@@ -279,6 +294,9 @@ int yaffs_CheckpointRead(yaffs_Device *dev, void *data, int nBytes)
 	if(!dev->checkpointBuffer)
 		return 0;
 
+	if(dev->checkpointOpenForWrite)
+		return -1;
+
 	while(i < nBytes && ok) {
 	
 	
@@ -320,6 +338,8 @@ int yaffs_CheckpointRead(yaffs_Device *dev, void *data, int nBytes)
 		
 		if(ok){
 			*dataBytes = dev->checkpointBuffer[dev->checkpointByteOffset];
+			dev->checkpointSum += *dataBytes;
+			dev->checkpointXor ^= *dataBytes;
 			dev->checkpointByteOffset++;
 			i++;
 			dataBytes++;