fix block store file appender (#658)

* fix bug where we write buffered data instead of provided data in BlockStoreFileAppender

1 files changed, 43 insertions, 3 deletions

diff --git a/src/zenstore/blockstore.cpp b/src/zenstore/blockstore.cpp
index d94643fa7..6c5b50f58 100644
--- a/src/zenstore/blockstore.cpp
+++ b/src/zenstore/blockstore.cpp
@@ -249,8 +249,8 @@ public:
 		{
 			Flush();
 
+			m_BlockFile.Write(Data, Size, m_WritePos);
 			const uint64_t WrittenPos = m_WritePos;
-			m_BlockFile.Write(m_Buffer, Size, m_BufferStart);
 			m_WritePos += Size;
 			m_BufferStart = m_WritePos;
 			return WrittenPos;
@@ -265,9 +265,9 @@ public:
 		}
 
 		ZEN_ASSERT((m_WritePos - m_BufferStart) + Size <= m_BufferSize);
-
-		const uint64_t WrittenPos = m_WritePos;
+		ZEN_ASSERT_SLOW(RoundUp(m_WritePos, Alignment) == m_WritePos);
 		memmove(&m_Buffer[m_WritePos - m_BufferStart], Data, Size);
+		const uint64_t WrittenPos = m_WritePos;
 		m_WritePos += Size;
 		return WrittenPos;
 	}
@@ -2374,6 +2374,46 @@ TEST_CASE("blockstore.compact.blocks")
 	}
 }
 
+TEST_CASE("blockstore.BlockStoreFileAppender")
+{
+	const uint64_t kMaxChunkSize = 32u * 1024u;
+	const size_t   kBlobCount	 = 753u;
+	const size_t   kAlignment	 = 32u;
+
+	ScopedTemporaryDirectory Tmp;
+	BlockStoreFile			 Block(Tmp.Path() / "block.0");
+	Block.Create(kMaxChunkSize * kBlobCount);
+
+	std::vector<IoHash>						   BlobHashes;
+	std::vector<std::pair<uint64_t, uint64_t>> BlobOffsetAndSize;
+	BlobHashes.reserve(kBlobCount);
+	BlobOffsetAndSize.reserve(kBlobCount);
+	{
+		BlockStoreFileAppender Appender(Block, 16u * 1024u);
+
+		FastRandom Random;
+		for (size_t Index = 0; Index < kBlobCount; Index++)
+		{
+			IoBuffer Blob	  = CreateRandomBlob(Random, Random.Next() % 32u * 1024u + 64u);
+			IoHash	 BlobHash = IoHash::HashBuffer(Blob);
+			BlobHashes.push_back(BlobHash);
+			uint64_t Offset = Appender.Append(Blob.GetData(), Blob.GetSize(), kAlignment);
+			BlobOffsetAndSize.push_back({Offset, Blob.GetSize()});
+		}
+	}
+
+	for (size_t Index = 0; Index < kBlobCount; Index++)
+	{
+		const IoHash& BlobHash		 = BlobHashes[Index];
+		uint64_t	  Offset		 = BlobOffsetAndSize[Index].first;
+		uint64_t	  Size			 = BlobOffsetAndSize[Index].second;
+		IoBuffer	  Blob			 = Block.GetChunk(Offset, Size);
+		IoHash		  VerifyBlobHash = IoHash::HashBuffer(Blob);
+		CHECK(BlobHash == VerifyBlobHash);
+		BlobOffsetAndSize.push_back({Offset, Blob.GetSize()});
+	}
+}
+
 #endif
 
 void