1 files changed, 79 insertions, 0 deletions
diff --git a/src/inc/sigbuilder.h b/src/inc/sigbuilder.h
new file mode 100644
index 0000000000..6d7cbf27ba
--- /dev/null
+++ b/src/inc/sigbuilder.h
@@ -0,0 +1,79 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+
+#ifndef _SIGBUILDER_H_
+#define _SIGBUILDER_H_
+
+#include "contract.h"
+
+//
+// Simple signature builder
+//
+
+class SigBuilder
+{
+    PBYTE m_pBuffer;
+    DWORD m_dwLength;
+    DWORD m_dwAllocation;
+
+    // Preallocate space for small signatures
+    BYTE m_prealloc[64];
+
+    // Grow the buffer to get at least cbMin of free space
+    void Grow(SIZE_T cbMin);
+
+    // Ensure that the buffer has at least cbMin of free space
+    FORCEINLINE void Ensure(SIZE_T cb)
+    {
+        if (m_dwAllocation - m_dwLength < cb)
+            Grow(cb);
+    }
+
+public:
+    SigBuilder()
+        : m_pBuffer(m_prealloc), m_dwLength(0), m_dwAllocation(sizeof(m_prealloc))
+    {
+        LIMITED_METHOD_CONTRACT;
+    }
+
+    ~SigBuilder();
+    
+    SigBuilder(DWORD cbPreallocationSize);
+    
+    PVOID GetSignature(DWORD * pdwLength)
+    {
+        LIMITED_METHOD_CONTRACT;
+        *pdwLength = m_dwLength;
+        return m_pBuffer;
+    }
+
+    DWORD GetSignatureLength()
+    {
+        LIMITED_METHOD_CONTRACT;
+        return m_dwLength;
+    }
+
+    void AppendByte(BYTE b);
+
+    void AppendData(ULONG data);
+
+    void AppendElementType(CorElementType etype)
+    {
+        WRAPPER_NO_CONTRACT;
+        AppendByte(static_cast<BYTE>(etype));
+    }
+
+    void AppendToken(mdToken tk);
+
+    void AppendPointer(void * ptr)
+    {
+        WRAPPER_NO_CONTRACT;
+        AppendBlob(&ptr, sizeof(ptr));
+    }
+
+    void AppendBlob(const PVOID pBlob, SIZE_T cbBlob);
+};
+
+#endif // _SIGBUILDER_H_