From be6aaa157f66a1761169b4205c696fdf1be2df10 Mon Sep 17 00:00:00 2001
From: kimchy <kimchy@gmail.com>
Date: Thu, 8 Jul 2010 22:18:26 +0300
Subject: [PATCH] fixed a bug in fs translog where it wasn't seeking correctly,
 and not counting the number of operations

---
 .../java/org/elasticsearch/index/translog/fs/FsSnapshot.java   | 2 ++
 .../java/org/elasticsearch/index/translog/fs/FsTranslog.java   | 3 ++-
 .../elasticsearch/index/translog/memory/MemoryTranslog.java    | 2 +-
 .../index/translog/AbstractSimpleTranslogTests.java            | 3 +++
 4 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/modules/elasticsearch/src/main/java/org/elasticsearch/index/translog/fs/FsSnapshot.java b/modules/elasticsearch/src/main/java/org/elasticsearch/index/translog/fs/FsSnapshot.java
index e2dff0f3de6..6af94ed1d44 100644
--- a/modules/elasticsearch/src/main/java/org/elasticsearch/index/translog/fs/FsSnapshot.java
+++ b/modules/elasticsearch/src/main/java/org/elasticsearch/index/translog/fs/FsSnapshot.java
@@ -78,6 +78,8 @@ public class FsSnapshot implements Translog.Snapshot {
             int opSize = dis.readInt();
             position += 4;
             if ((position + opSize) > length) {
+                // restore the position to before we read the opSize
+                position -= 4;
                 return false;
             }
             position += opSize;
diff --git a/modules/elasticsearch/src/main/java/org/elasticsearch/index/translog/fs/FsTranslog.java b/modules/elasticsearch/src/main/java/org/elasticsearch/index/translog/fs/FsTranslog.java
index 0afecd3ef8b..f24b54ccb84 100644
--- a/modules/elasticsearch/src/main/java/org/elasticsearch/index/translog/fs/FsTranslog.java
+++ b/modules/elasticsearch/src/main/java/org/elasticsearch/index/translog/fs/FsTranslog.java
@@ -108,6 +108,7 @@ public class FsTranslog extends AbstractIndexShardComponent implements Translog
                 bosOs.flush();
                 raf.raf().writeInt(bos.size());
                 raf.raf().write(bos.unsafeByteArray(), 0, bos.size());
+                operationCounter.incrementAndGet();
             } catch (Exception e) {
                 throw new TranslogException(shardId, "Failed to write operation [" + operation + "]", e);
             }
@@ -134,7 +135,7 @@ public class FsTranslog extends AbstractIndexShardComponent implements Translog
                 FsSnapshot fsSnapshot = (FsSnapshot) snapshot;
                 raf.increaseRefCount();
                 FsSnapshot newSnapshot = new FsSnapshot(shardId, id, raf, raf.raf().getFilePointer());
-                newSnapshot.seekForward(fsSnapshot.length());
+                newSnapshot.seekForward(fsSnapshot.position());
                 return newSnapshot;
             } catch (IOException e) {
                 throw new TranslogException(shardId, "Failed to snapshot", e);
diff --git a/modules/elasticsearch/src/main/java/org/elasticsearch/index/translog/memory/MemoryTranslog.java b/modules/elasticsearch/src/main/java/org/elasticsearch/index/translog/memory/MemoryTranslog.java
index 6d6d7e17e73..af0a112e6d1 100644
--- a/modules/elasticsearch/src/main/java/org/elasticsearch/index/translog/memory/MemoryTranslog.java
+++ b/modules/elasticsearch/src/main/java/org/elasticsearch/index/translog/memory/MemoryTranslog.java
@@ -95,7 +95,7 @@ public class MemoryTranslog extends AbstractIndexShardComponent implements Trans
                 return snapshot();
             }
             MemorySnapshot newSnapshot = new MemorySnapshot(currentId(), operations, operationCounter.get());
-            newSnapshot.seekForward(memorySnapshot.length());
+            newSnapshot.seekForward(memorySnapshot.position());
             return newSnapshot;
         }
     }
diff --git a/modules/elasticsearch/src/test/java/org/elasticsearch/index/translog/AbstractSimpleTranslogTests.java b/modules/elasticsearch/src/test/java/org/elasticsearch/index/translog/AbstractSimpleTranslogTests.java
index 861537f9299..15ac5ca2840 100644
--- a/modules/elasticsearch/src/test/java/org/elasticsearch/index/translog/AbstractSimpleTranslogTests.java
+++ b/modules/elasticsearch/src/test/java/org/elasticsearch/index/translog/AbstractSimpleTranslogTests.java
@@ -124,6 +124,9 @@ public abstract class AbstractSimpleTranslogTests {
         snapshot.release();
 
         Translog.Snapshot snapshot1 = translog.snapshot();
+        // we use the translogSize to also navigate to the last position on this snapshot
+        // so snapshot(Snapshot) will work properly
+        assertThat(snapshot1, translogSize(1));
 
         translog.add(new Translog.Index("test", "2", new byte[]{2}));
         snapshot = translog.snapshot(snapshot1);