Added some argument validation

1 files changed, 17 insertions, 3 deletions

diff --git a/zencore/iobuffer.cpp b/zencore/iobuffer.cpp
index 54f0d8fa4..9c7781663 100644
--- a/zencore/iobuffer.cpp
+++ b/zencore/iobuffer.cpp
@@ -47,9 +47,11 @@ IoBufferCore::FreeBuffer()
 
 //////////////////////////////////////////////////////////////////////////
 
+static_assert(sizeof(IoBufferCore) == 32);
+
 IoBufferCore::IoBufferCore(size_t InSize)
 {
-	static_assert(sizeof(IoBufferCore) == 32);
+	ZEN_ASSERT(InSize);
 
 	m_DataPtr	= AllocateBuffer(InSize, sizeof(void*));
 	m_DataBytes = InSize;
@@ -59,6 +61,8 @@ IoBufferCore::IoBufferCore(size_t InSize)
 
 IoBufferCore::IoBufferCore(size_t InSize, size_t Alignment)
 {
+	ZEN_ASSERT(InSize);
+
 	m_DataPtr	= AllocateBuffer(InSize, Alignment);
 	m_DataBytes = InSize;
 
@@ -322,9 +326,11 @@ IoBufferBuilder::MakeFromFile(const wchar_t* FileName, uint64_t Offset, uint64_t
 		ULONGLONG FileSize;
 		DataFile.GetSize(FileSize);
 
+		// TODO: should validate that offset is in range
+
 		if (Size == ~0ull)
 		{
-			Size = FileSize;
+			Size = FileSize - Offset;
 		}
 		else
 		{
@@ -335,7 +341,15 @@ IoBufferBuilder::MakeFromFile(const wchar_t* FileName, uint64_t Offset, uint64_t
 			}
 		}
 
-		return IoBuffer(IoBuffer::File, DataFile.Detach(), Offset, Size);
+		if (Size)
+		{
+			return IoBuffer(IoBuffer::File, DataFile.Detach(), Offset, Size);
+		}
+		else
+		{
+			// For an empty file, we may as well just return an empty memory IoBuffer
+			return IoBuffer(IoBuffer::Wrap, "", 0);
+		}
 	}
 
 	return {};