From 74327613aca056f76da21b2e421b1196d02f84f5 Mon Sep 17 00:00:00 2001
From: Badrish Chandramouli <badrishc@microsoft.com>
Date: Thu, 26 Dec 2019 18:54:03 -0800
Subject: [PATCH] FasterLog iterator fixes. (#222)

Use requestedCompletedUntilAddress correctly.
Expose recovered iterators to user.
---
 cs/src/core/Index/FasterLog/FasterLog.cs             | 6 +++++-
 cs/src/core/Index/FasterLog/FasterLogIterator.cs     | 2 +-
 cs/src/core/Index/FasterLog/FasterLogRecoveryInfo.cs | 4 ++--
 3 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/cs/src/core/Index/FasterLog/FasterLog.cs b/cs/src/core/Index/FasterLog/FasterLog.cs
index f8994a962..832a73b75 100644
--- a/cs/src/core/Index/FasterLog/FasterLog.cs
+++ b/cs/src/core/Index/FasterLog/FasterLog.cs
@@ -25,7 +25,6 @@ public class FasterLog : IDisposable
         private readonly GetMemory getMemory;
         private readonly int headerSize;
         private readonly LogChecksumType logChecksum;
-        private readonly Dictionary<string, long> RecoveredIterators;
         private TaskCompletionSource<LinkedCommitInfo> commitTcs
             = new TaskCompletionSource<LinkedCommitInfo>(TaskCreationOptions.RunContinuationsAsynchronously);
 
@@ -44,6 +43,11 @@ private TaskCompletionSource<LinkedCommitInfo> commitTcs
         /// </summary>
         public long FlushedUntilAddress => allocator.FlushedUntilAddress;
 
+        /// <summary>
+        /// Dictionary of recovered iterators and their committed until addresses
+        /// </summary>
+        public readonly Dictionary<string, long> RecoveredIterators;
+
         /// <summary>
         /// Log committed until address
         /// </summary>
diff --git a/cs/src/core/Index/FasterLog/FasterLogIterator.cs b/cs/src/core/Index/FasterLog/FasterLogIterator.cs
index 8efb1d3fd..d729ca0f2 100644
--- a/cs/src/core/Index/FasterLog/FasterLogIterator.cs
+++ b/cs/src/core/Index/FasterLog/FasterLogIterator.cs
@@ -31,7 +31,7 @@ public class FasterLogScanIterator : IDisposable
         private readonly GetMemory getMemory;
         private readonly int headerSize;
         private bool disposed = false;
-        private long requestedCompletedUntilAddress;
+        internal long requestedCompletedUntilAddress;
 
         /// <summary>
         /// Next address
diff --git a/cs/src/core/Index/FasterLog/FasterLogRecoveryInfo.cs b/cs/src/core/Index/FasterLog/FasterLogRecoveryInfo.cs
index 829beece2..9a2b9f71b 100644
--- a/cs/src/core/Index/FasterLog/FasterLogRecoveryInfo.cs
+++ b/cs/src/core/Index/FasterLog/FasterLogRecoveryInfo.cs
@@ -147,7 +147,7 @@ public void SnapshotIterators(ConcurrentDictionary<string, FasterLogScanIterator
 
                 foreach (var kvp in persistedIterators)
                 {
-                    Iterators.Add(kvp.Key, kvp.Value.CompletedUntilAddress);
+                    Iterators.Add(kvp.Key, kvp.Value.requestedCompletedUntilAddress);
                 }
             }
         }
@@ -162,7 +162,7 @@ public void CommitIterators(ConcurrentDictionary<string, FasterLogScanIterator>
             {
                 foreach (var kvp in Iterators)
                 {
-                    persistedIterators[kvp.Key].CompletedUntilAddress = kvp.Value;
+                    persistedIterators[kvp.Key].UpdateCompletedUntilAddress(kvp.Value);
                 }
             }
         }