minor zenstore/blockstore fixes (#821)

- Fix clang-format error accidentally introduced by recent PR
- Fix `FileSize()` CAS race that repeatedly invalidated the cache when concurrent callers both missed; remove `store(0)` on CAS failure
- Fix `WriteChunks` not accounting for initial alignment padding in `m_TotalSize`, causing drift vs `WriteChunk`'s correct accounting
- Fix Create retry sleep computing negative values (100 - N*100 instead of 100 + N*100), matching the Open retry pattern
- Fix `~BlockStore` error log missing format placeholder for `Ex.what()`
- Fix `GetFreeBlockIndex` infinite loop when all indexes have orphan files on disk but aren't in `m_ChunkBlocks`; bound probe to `m_MaxBlockCount`
- Fix `IterateBlock` ignoring `SmallSizeCallback` return value for single out-of-bounds chunks, preventing early termination
- Fix `BlockStoreCompactState::IterateBlocks` iterating map by value instead of const reference

1 files changed, 12 insertions, 12 deletions

diff --git a/src/zenstore/blockstore.cpp b/src/zenstore/blockstore.cpp
index 6197c7f24..6528fcb2f 100644
--- a/src/zenstore/blockstore.cpp
+++ b/src/zenstore/blockstore.cpp
@@ -98,7 +98,7 @@ BlockStoreFile::Create(uint64_t InitialSize)
 			return false;
 		}
 		ZEN_WARN("Failed to create cas block '{}', reason: '{}', retries left: {}.", m_Path, Ec.message(), RetriesLeft);
-		Sleep(100 - (3 - RetriesLeft) * 100);  // Total 600 ms
+		Sleep(100 + (3 - RetriesLeft) * 100);  // Total 600 ms
 		RetriesLeft--;
 		return true;
 	});
@@ -125,11 +125,7 @@ BlockStoreFile::FileSize() const
 			return 0;
 		}
 		uint64_t Expected = 0;
-		if (!m_CachedFileSize.compare_exchange_strong(Expected, Size))
-		{
-			// Force a new check next time file size is fetched
-			m_CachedFileSize.store(0);
-		}
+		m_CachedFileSize.compare_exchange_strong(Expected, Size);
 		return Size;
 	}
 	return CachedSize;
@@ -388,7 +384,7 @@ BlockStore::~BlockStore()
 	}
 	catch (const std::exception& Ex)
 	{
-		ZEN_ERROR("~BlockStore() failed with: ", Ex.what());
+		ZEN_ERROR("~BlockStore() failed with: {}", Ex.what());
 	}
 }
 
@@ -624,7 +620,7 @@ BlockStore::GetFreeBlockIndex(uint32_t ProbeIndex, RwLock::ExclusiveLockScope&,
 		return (uint32_t)m_MaxBlockCount;
 	}
 
-	while (true)
+	for (uint64_t ProbeCount = 0; ProbeCount < m_MaxBlockCount; ++ProbeCount)
 	{
 		if (!m_ChunkBlocks.contains(ProbeIndex))
 		{
@@ -645,7 +641,7 @@ BlockStore::GetFreeBlockIndex(uint32_t ProbeIndex, RwLock::ExclusiveLockScope&,
 		}
 		ProbeIndex = (ProbeIndex + 1) & (m_MaxBlockCount - 1);
 	}
-	return ProbeIndex;
+	return (uint32_t)m_MaxBlockCount;
 }
 
 void
@@ -808,6 +804,7 @@ BlockStore::WriteChunks(std::span<const IoBuffer> Datas, uint32_t Alignment, con
 			Count++;
 			RangeSize = NextRangeSize;
 		}
+		uint32_t AlignmentPadding	   = AlignedInsertOffset - m_CurrentInsertOffset;
 		m_CurrentInsertOffset		   = AlignedInsertOffset + RangeSize;
 		Ref<BlockStoreFile> WriteBlock = m_WriteBlock;
 		AddActiveWriteBlock(InsertLock, WriteBlockIndex);
@@ -829,13 +826,13 @@ BlockStore::WriteChunks(std::span<const IoBuffer> Datas, uint32_t Alignment, con
 				WriteBuffer.MidInline(RoundUp(SourceBuffer.GetSize(), Alignment));
 			}
 			WriteBlock->Write(Buffer.data(), RangeSize, AlignedInsertOffset);
-			m_TotalSize.fetch_add(RangeSize, std::memory_order::relaxed);
+			m_TotalSize.fetch_add(AlignmentPadding + RangeSize, std::memory_order::relaxed);
 		}
 		else
 		{
 			MemoryView SourceBuffer = Datas[Offset];
 			WriteBlock->Write(SourceBuffer.GetData(), SourceBuffer.GetSize(), AlignedInsertOffset);
-			m_TotalSize.fetch_add(SourceBuffer.GetSize(), std::memory_order::relaxed);
+			m_TotalSize.fetch_add(AlignmentPadding + SourceBuffer.GetSize(), std::memory_order::relaxed);
 		}
 
 		uint32_t						ChunkOffset = AlignedInsertOffset;
@@ -1087,7 +1084,10 @@ BlockStore::IterateBlock(std::span<const BlockStoreLocation>   ChunkLocations,
 							  BlockIndex,
 							  BlockSize);
 
-				SmallSizeCallback(ChunkIndex, nullptr, 0);
+				if (!SmallSizeCallback(ChunkIndex, nullptr, 0))
+				{
+					return false;
+				}
 				LocationIndexOffset++;
 				continue;
 			}