From 9d40c679744502a1c82cf5ed94e14a10ec6647a6 Mon Sep 17 00:00:00 2001
From: Jarrod Johnson <jjohnson2@lenovo.com>
Date: Sun, 13 Mar 2016 19:50:02 -0400
Subject: [PATCH] Support walking back through multiple logs

The rollback support and replaydid not follow more than one log back.  Do the work to recurse
into older and older files, until big enough buffer or run out of files.
---
 confluent_server/confluent/log.py | 45 ++++++++++++++++++-------------
 1 file changed, 26 insertions(+), 19 deletions(-)

diff --git a/confluent_server/confluent/log.py b/confluent_server/confluent/log.py
index 6897c95e..5ba577ee 100644
--- a/confluent_server/confluent/log.py
+++ b/confluent_server/confluent/log.py
@@ -1,7 +1,7 @@
 # vim: tabstop=4 shiftwidth=4 softtabstop=4
 
 # Copyright 2014 IBM Corporation
-# Copyright 2015 Lenovo
+# Copyright 2015-2016 Lenovo
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -604,7 +604,6 @@ class Logger(object):
         offsets = []
         termstate = None
         recenttimestamp = 0
-        access_last_rename = False
         flock(textfile, LOCK_SH)
         while binidx > 0 and currsize < size:
             binidx -= 16
@@ -614,23 +613,21 @@ class Logger(object):
                 struct.unpack(">BBIHIBBH", recbytes)
             # rolling events found.
             if ltype == DataTypes.event and evtdata == Events.logrollover:
-                # Now, we can only find the last renamed file which logging
-                # the data.
-                if access_last_rename == False:
-                    access_last_rename = True
-                else:
-                    break
                 textpath, binpath = parse_last_rolling_files(textfile, offset,
                                                              datalen)
                 # Rolling event detected, close the current bin file, then open
                 # the renamed bin file.
                 flock(binfile, LOCK_UN)
+                flock(textfile, LOCK_UN)
                 binfile.close()
+                textfile.close()
                 try:
                     binfile = open(binpath, mode='r')
+                    textfile = open(textpath, mode='r')
                 except IOError:
-                    return '', 0, 0
+                    break
                 flock(binfile, LOCK_SH)
+                flock(textfile, LOCK_SH)
                 binfile.seek(0, 2)
                 binidx = binfile.tell()
                 # things have been set up for next iteration to dig to
@@ -644,22 +641,32 @@ class Logger(object):
             offsets.append((offset, datalen, textpath))
             if termstate is None:
                 termstate = eventaux
-        flock(binfile, LOCK_UN)
-        binfile.close()
+        try:
+            flock(binfile, LOCK_UN)
+            binfile.close()
+        except:
+            pass
         textdata = ''
         while offsets:
             (offset, length, textpath) = offsets.pop()
             if textfile.name != textpath:
-                flock(textfile, LOCK_UN)
-                textfile.close()
                 try:
-                    textfile = open(textpath)
-                except IOError:
-                    return '', 0, 0
-            textfile.seek(offset, 0)
+                    flock(textfile, LOCK_UN)
+                    textfile.close()
+                    textfile = open(textpath, mode='r')
+                except (ValueError, IOError) as e:
+                    break
+            try:
+                textfile.seek(offset, 0)
+            except ValueError:
+                # file was closed, settle with what we have and continue
+                break
             textdata += textfile.read(length)
-        flock(textfile, LOCK_UN)
-        textfile.close()
+        try:
+            flock(textfile, LOCK_UN)
+            textfile.close()
+        except:
+            pass
         if termstate is None:
             termstate = 0
         return textdata, termstate, recenttimestamp