[Linux-NTFS-cvs] CVS: linux-ntfs/libntfs volume.c,1.52,1.53

[? <sz...@us...>]

Changes by: szaka

Update of /cvsroot/linux-ntfs/linux-ntfs/libntfs
In directory usw-pr-cvs1:/tmp/cvs-serv11567/libntfs

Modified Files:
	volume.c 
Log Message:
Rewrote $LogFile reset using new inode API and moved it from ntfsfix to
libntfs as ntfs_reset_logfile(). ntfsresize also resets log file.


Index: volume.c
===================================================================
RCS file: /cvsroot/linux-ntfs/linux-ntfs/libntfs/volume.c,v
retrieving revision 1.52
retrieving revision 1.53
diff -U2 -r1.52 -r1.53
--- volume.c	12 Jul 2002 08:18:15 -0000	1.52
+++ volume.c	12 Jul 2002 12:38:54 -0000	1.53
@@ -917,2 +917,93 @@
 	return -1;
 }
+
+/**
+ * ntfs_reset_logfile - "empty" $LogFile data attribute value
+ * @vol:	ntfs volume whose $LogFile we intend to reset.
+ *
+ * Fill the value of the $LogFile data attribute, i.e. the contents of
+ * the file, with 0xff's, thus marking the journal as empty.
+ * FIXME(?): We might need to zero the LSN field of every single mft
+ * record as well. (But, first try without doing that and see what
+ * happens, since chkdsk might pickup the pieces and do it for us...)
+ *
+ * On success return 0.
+ *
+ * On error, return -1 with errno set to the error code.
+ */
+int ntfs_reset_logfile(ntfs_volume *vol)
+{
+	ntfs_inode *ni;
+	ntfs_attr *na;
+	s64 len, pos, count;
+	char buf[NTFS_BUF_SIZE];
+
+	if ((ni = ntfs_open_inode(vol, FILE_LogFile)) == NULL) {
+		Dperror("Failed to open inode FILE_LogFile.\n");
+		return -1;
+	}
+
+	if ((na = ntfs_attr_open(ni, AT_DATA, AT_NONAME, 0)) == NULL) {
+		Dperror("Failed to open $FILE_LogFile/$DATA\n");
+		return -1;
+	}
+	
+	/* The $DATA attribute of the $LogFile has to be non-resident. */
+	if (!NAttrNonResident(na)) {
+		Dprintf("$LogFile $DATA attribute is resident!?!\n");
+		errno = EIO;
+		return -1;
+	}
+
+	/* Get length of $LogFile contents. */
+	len = na->data_size;
+	if (!len) {
+		Dprintf("$LogFile has zero length, no disk write needed.\n");
+		return 0;
+	}
+	
+	/* Read $LogFile until its end. We do this as a check for correct 
+	   length thus making sure we are decompressing the mapping pairs 
+	   array correctly and hence writing below is safe as well. */
+	pos = 0;
+	while (1) {
+		count = ntfs_attr_pread(na, pos, NTFS_BUF_SIZE, buf);
+		if (count == -1)
+			break;
+		
+		pos += count;
+		if (count != NTFS_BUF_SIZE || !count)
+			break;
+	}
+
+	if (count == -1 || pos != len) {
+		Dprintf("Amount of $LogFile data read does not "
+			"correspond to expected length!");
+		if (count != -1)
+			errno = EIO;
+		return -1;
+	}
+
+	/* Fill the buffer with 0xff's. */
+	memset(buf, -1, NTFS_BUF_SIZE);
+
+	/* Set the $DATA attribute. */
+	pos = 0;
+	while ((count = len - pos) > 0) {
+		if (count > NTFS_BUF_SIZE)
+			count = NTFS_BUF_SIZE;
+		
+		if (count != ntfs_attr_pwrite(na, pos, count, buf)) {
+			Dprintf("Failed to set the $LogFile attribute value.");
+			if (count != -1)
+				errno = EIO;
+			return -1;
+		}
+		pos += count;
+	}
+	
+	ntfs_attr_close(na);
+	
+	return ntfs_close_inode(ni);
+}
+