gluster-blockd: implement transaction framework

This patch introduce the transaction locking also, start maintaining
meta data journaling per block

Every request is follows transaction, at the start of any transaction
we take blocking lock on "/block-meta/meta.lock" file and at the end
we unlock.

Meanwhile while, when the transaction is in progress we do
journaling, while performing series of operations, used for future
purposes and roll backing.

A sample journal file looks like:
$ cat  /mnt/block-meta/LUN1
GBID: xyz-abc
SIZE : 5GiB
HA: 3
ENTRYCREATE: INPROGRESS
ENTRYCREATE: SUCCESS
NODE1: INPROGRESS
NODE2: INPROGRESS
NODE3: INPROGRESS
NODE2: SUCCESS
NODE3: FAIL
NODE1: SUCCESS
NODE4: INPROGRESS
NODE4: SUCCESS
NODE3: CLEANUPSUCCESS
<EOF>

Signed-off-by: Prasanna Kumar Kalever <prasanna.kalever@redhat.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/common.h b/common.h
index 46d40ee..4898fe7 100644
--- a/common.h
+++ b/common.h
@@ -14,6 +14,8 @@
 
 # include "utils.h"
 
+# define  LOG_FILE         "/var/log/gluster-block/block.log"
+# define  LOG_LEVEL        7
 
 size_t glusterBlockCreateParseSize(char *value);