improved lock file handling (#50)

- Feature: `zen down`
  - --`data-dir` to specify a data directory to deduce which zen instance to bring down
- Feature: `zen attach`
  - --`data-dir` to specify a data directory to deduce which zen instance to attach to222
  
- Feature: `zen status`
  -  --`port` filter running zen instances based on port
  - --`data-dir` filter running zen instances based on information in the data directory

- Improvement: Trying to load a compact binary object from an empty file no longer causes access violation

1 files changed, 20 insertions, 2 deletions

diff --git a/src/zencore/compactbinary.cpp b/src/zencore/compactbinary.cpp
index 0907f8a2e..029889e85 100644
--- a/src/zencore/compactbinary.cpp
+++ b/src/zencore/compactbinary.cpp
@@ -1421,25 +1421,43 @@ LoadCompactBinary(BinaryReader& Ar, BufferAllocator Allocator)
 CbObject
 LoadCompactBinaryObject(IoBuffer&& Payload)
 {
+	if (Payload.GetSize() == 0)
+	{
+		return CbObject();
+	}
 	return CbObject{SharedBuffer(std::move(Payload))};
 }
 
 CbObject
 LoadCompactBinaryObject(const IoBuffer& Payload)
 {
+	if (Payload.GetSize() == 0)
+	{
+		return CbObject();
+	}
 	return CbObject{SharedBuffer(Payload)};
 }
 
 CbObject
 LoadCompactBinaryObject(CompressedBuffer&& Payload)
 {
-	return CbObject{SharedBuffer(Payload.DecompressToComposite().Flatten())};
+	CompositeBuffer Decompressed = std::move(Payload).DecompressToComposite();
+	if (Decompressed.GetSize() == 0)
+	{
+		return CbObject();
+	}
+	return CbObject{std::move(Decompressed).Flatten()};
 }
 
 CbObject
 LoadCompactBinaryObject(const CompressedBuffer& Payload)
 {
-	return CbObject{SharedBuffer(Payload.DecompressToComposite().Flatten())};
+	CompositeBuffer Decompressed = Payload.DecompressToComposite();
+	if (Decompressed.GetSize() == 0)
+	{
+		return CbObject();
+	}
+	return CbObject{std::move(Decompressed).Flatten()};
 }
 
 //////////////////////////////////////////////////////////////////////////