special treatment large oplog attachments v2 (#5)

- Bugfix: Install Ctrl+C handler earlier when doing `zen oplog-export` and `zen oplog-export` to properly cancel jobs
- Improvement: Add ability to block a set of CAS entries from GC in project store
- Improvement: Large attachments and loose files are now split into smaller chunks and stored in blocks during oplog export

1 files changed, 54 insertions, 0 deletions

diff --git a/src/zenstore/include/zenstore/chunkedfile.h b/src/zenstore/include/zenstore/chunkedfile.h
new file mode 100644
index 000000000..c6330bdbd
--- /dev/null
+++ b/src/zenstore/include/zenstore/chunkedfile.h
@@ -0,0 +1,54 @@
+// Copyright Epic Games, Inc. All Rights Reserved.
+
+#pragma once
+
+#include <zencore/iobuffer.h>
+#include <zencore/iohash.h>
+#include <zencore/zencore.h>
+
+#include <functional>
+#include <vector>
+
+namespace zen {
+
+class BasicFile;
+
+struct ChunkedInfo
+{
+	uint64_t			  RawSize = 0;
+	IoHash				  RawHash;
+	std::vector<uint32_t> ChunkSequence;
+	std::vector<IoHash>	  ChunkHashes;
+};
+
+struct ChunkSource
+{
+	uint64_t Offset;  // 8
+	uint32_t Size;	  // 4
+};
+
+struct ChunkedInfoWithSource
+{
+	ChunkedInfo				 Info;
+	std::vector<ChunkSource> ChunkSources;
+};
+
+struct ChunkedParams
+{
+	bool   UseThreshold = true;
+	size_t MinSize		= (2u * 1024u) - 128u;
+	size_t MaxSize		= (16u * 1024u);
+	size_t AvgSize		= (3u * 1024u);
+};
+
+static const ChunkedParams UShaderByteCodeParams = {.UseThreshold = true, .MinSize = 17280, .MaxSize = 139264, .AvgSize = 36340};
+
+ChunkedInfoWithSource ChunkData(BasicFile& RawData, uint64_t Offset, uint64_t Size, ChunkedParams Params = {});
+void				  Reconstruct(const ChunkedInfo&							   Info,
+								  const std::filesystem::path&					   TargetPath,
+								  std::function<IoBuffer(const IoHash& ChunkHash)> GetChunk);
+IoBuffer			  SerializeChunkedInfo(const ChunkedInfo& Info);
+ChunkedInfo			  DeserializeChunkedInfo(IoBuffer& Buffer);
+
+void chunkedfile_forcelink();
+}  // namespace zen