Implement lsn_to_bytes bytes_to_lsn functions

helpers/utils.py

@@ -6,6 +6,32 @@ import time
 received_sigchld = False
 
 
+def lsn_to_bytes(value):
+    """
+    >>> lsn_to_bytes('1/66000060')
+    6006243424
+    >>> lsn_to_bytes('j/66000060')
+    0
+    """
+    try:
+        e = value.split('/')
+        if len(e) == 2 and len(e[0]) > 0 and len(e[1]) > 0:
+            return (int(e[0], 16) << 32) | int(e[1], 16)
+    except ValueError:
+        pass
+    return 0
+
+
+def bytes_to_lsn(value):
+    """
+    >>> bytes_to_lsn(6006243424)
+    '1/66000060'
+    """
+    id = value >> 32
+    off = value & 0xffffffff
+    return '%x/%x' % (id, off)
+
+
 def sigterm_handler(signo, stack_frame):
     sys.exit()