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, 21 insertions, 9 deletions

diff --git a/src/zencore/compress.cpp b/src/zencore/compress.cpp
index c41bdac42..a8e8a79f4 100644
--- a/src/zencore/compress.cpp
+++ b/src/zencore/compress.cpp
@@ -193,15 +193,7 @@ class NoneEncoder final : public BaseEncoder
 public:
 	[[nodiscard]] CompositeBuffer Compress(const CompositeBuffer& RawData, uint64_t /* BlockSize */) const final
 	{
-		BufferHeader Header;
-		Header.Method			   = CompressionMethod::None;
-		Header.BlockCount		   = 1;
-		Header.TotalRawSize		   = RawData.GetSize();
-		Header.TotalCompressedSize = Header.TotalRawSize + sizeof(BufferHeader);
-		Header.RawHash			   = BLAKE3::HashBuffer(RawData);
-
-		UniqueBuffer HeaderData = UniqueBuffer::Alloc(sizeof(BufferHeader));
-		Header.Write(HeaderData);
+		UniqueBuffer HeaderData = CompressedBuffer::CreateHeaderForNoneEncoder(RawData.GetSize(), BLAKE3::HashBuffer(RawData));
 		return CompositeBuffer(HeaderData.MoveToShared(), RawData.MakeOwned());
 	}
 };
@@ -1301,6 +1293,26 @@ CompressedBuffer::ValidateCompressedHeader(const IoBuffer& CompressedData, IoHas
 	return detail::BufferHeader::IsValid(SharedBuffer(CompressedData), OutRawHash, OutRawSize);
 }
 
+size_t
+CompressedBuffer::GetHeaderSizeForNoneEncoder()
+{
+	return sizeof(detail::BufferHeader);
+}
+
+UniqueBuffer
+CompressedBuffer::CreateHeaderForNoneEncoder(uint64_t RawSize, const BLAKE3& RawHash)
+{
+	detail::BufferHeader Header;
+	Header.Method			   = detail::CompressionMethod::None;
+	Header.BlockCount		   = 1;
+	Header.TotalRawSize		   = RawSize;
+	Header.TotalCompressedSize = Header.TotalRawSize + sizeof(detail::BufferHeader);
+	Header.RawHash			   = RawHash;
+	UniqueBuffer HeaderData	   = UniqueBuffer::Alloc(sizeof(detail::BufferHeader));
+	Header.Write(HeaderData);
+	return HeaderData;
+}
+
 uint64_t
 CompressedBuffer::DecodeRawSize() const
 {