RawOffset can be anything and we expect an empty buffer to be returned along with RawSize = 0 if the offset was out of bounds for the value. (#666)

1 files changed, 23 insertions, 17 deletions

diff --git a/src/zenstore/cache/cacherpc.cpp b/src/zenstore/cache/cacherpc.cpp
index 4c44f43ca..09a3d0afc 100644
--- a/src/zenstore/cache/cacherpc.cpp
+++ b/src/zenstore/cache/cacherpc.cpp
@@ -2004,24 +2004,30 @@ CacheRpcHandler::WriteGetCacheChunksResponse([[maybe_unused]] const CacheRequest
 							}
 						}
 
-						CompressedBuffer PartialValue =
-							Ok ? Request.Value.GetRange(Request.RequestedOffset, Request.RequestedSize) : CompressedBuffer::Null;
-
-						if (PartialValue)
+						if (Ok)
 						{
-							uint64_t FragmentRawLength = PartialValue.DecodeRawSize();
-							ZEN_ASSERT(FragmentRawOffset <= Request.RequestedOffset);
-							ZEN_ASSERT(FragmentRawOffset + FragmentRawLength >= Request.RequestedOffset + Request.RequestedSize);
-
-							IoHashStream FragmentHashStream;
-							FragmentHashStream.Append(Request.Key->ChunkId.Hash, sizeof(Request.Key->ChunkId.Hash));
-							FragmentHashStream.Append(&FragmentRawOffset, sizeof(FragmentRawOffset));
-							FragmentHashStream.Append(&FragmentRawLength, sizeof(FragmentRawLength));
-							IoHash FragmentHash = FragmentHashStream.GetHash();
-
-							Writer.AddHash("FragmentHash", FragmentHash);
-							Writer.AddInteger("FragmentOffset", FragmentRawOffset);
-							RpcResponse.AddAttachment(CbAttachment(PartialValue, FragmentHash));
+							CompressedBuffer PartialValue = Request.Value.GetRange(Request.RequestedOffset, Request.RequestedSize);
+
+							if (PartialValue)
+							{
+								uint64_t FragmentRawLength = PartialValue.DecodeRawSize();
+								ZEN_ASSERT(FragmentRawOffset <= Request.RequestedOffset);
+
+								IoHashStream FragmentHashStream;
+								FragmentHashStream.Append(Request.Key->ChunkId.Hash, sizeof(Request.Key->ChunkId.Hash));
+								FragmentHashStream.Append(&FragmentRawOffset, sizeof(FragmentRawOffset));
+								FragmentHashStream.Append(&FragmentRawLength, sizeof(FragmentRawLength));
+								IoHash FragmentHash = FragmentHashStream.GetHash();
+
+								Writer.AddHash("FragmentHash", FragmentHash);
+								Writer.AddInteger("FragmentOffset", FragmentRawOffset);
+								RpcResponse.AddAttachment(CbAttachment(PartialValue, FragmentHash));
+							}
+							else
+							{
+								Writer.AddInteger("RawSize", 0);
+								Request.Exists = true;
+							}
 						}
 						else
 						{