OrcLib: ByteStream: add Clone() method to select Streams

src/OrcLib/ByteStream.h

@@ -69,10 +69,11 @@ class ORCLIB_API ByteStream
     STDMETHOD_(ULONG64, GetSize)() PURE;
     STDMETHOD(SetSize)(ULONG64) PURE;
 
+    STDMETHOD(Clone)(std::shared_ptr<ByteStream>& clone) { return E_NOTIMPL; }
+
     STDMETHOD(Close)() PURE;
 
     static std::shared_ptr<ByteStream> GetStream(const OutputSpec& output);
-
     static std::shared_ptr<ByteStream> GetHashStream(const std::shared_ptr<ByteStream>& aStream);
 
     static HRESULT Get_IInStream(const std::shared_ptr<ByteStream>& aStream, ::IInStream** pInStream);

src/OrcLib/FileStream.cpp

@@ -16,6 +16,24 @@
 
 using namespace Orc;
 
+STDMETHODIMP Orc::FileStream::Clone(std::shared_ptr<ByteStream>& clone)
+{
+    auto new_stream = std::make_shared<Orc::FileStream>();
+    if (auto hr = new_stream->Duplicate(*this); FAILED(hr))
+        return hr;
+
+    ULONG64 ullCurPos = 0LLU;
+    if (auto hr = SetFilePointer(0LL, FILE_CURRENT, &ullCurPos); FAILED(hr))
+        return hr;
+
+    ULONG64 ullDupCurPos = 0LLU;
+    if (auto hr = new_stream->SetFilePointer(ullCurPos, FILE_BEGIN, &ullDupCurPos); FAILED(hr))
+        return hr;
+
+    clone = new_stream;
+    return S_OK;
+}
+
 /*
     CFileStream::Close
 

src/OrcLib/FileStream.h

@@ -96,6 +96,7 @@ class ORCLIB_API FileStream : public ByteStream
 
     const std::wstring& Path() const { return m_strPath; }
 
+    STDMETHOD(Clone)(std::shared_ptr<ByteStream>& clone);
     STDMETHOD(Close)();
 
 protected:

src/OrcLib/MemoryStream.cpp

@@ -31,6 +31,25 @@ static const size_t MEMORY_STREAM_THRESHOLD_INCREMENT = (1024 * 1024 * 16);
 
 static const size_t MEMORY_STREAM_RESERVE_MAX = (1024 * 1024 * 200);
 
+STDMETHODIMP Orc::MemoryStream::Clone(std::shared_ptr<ByteStream>& clone)
+{
+    auto new_stream = std::make_shared<MemoryStream>();
+
+    if (auto hr = new_stream->Duplicate(*this); FAILED(hr))
+        return hr;
+
+    ULONG64 ullCurPos = 0LLU;
+    if (auto hr = SetFilePointer(0LL, FILE_CURRENT, &ullCurPos); FAILED(hr))
+        return hr;
+
+    ULONG64 ullDupCurPos = 0LLU;
+    if (auto hr = new_stream->SetFilePointer(ullCurPos, FILE_BEGIN, &ullDupCurPos); FAILED(hr))
+        return hr;
+
+    clone = new_stream;
+    return S_OK;
+}
+
 HRESULT MemoryStream::Close()
 {
     return S_OK;

src/OrcLib/MemoryStream.h

@@ -73,6 +73,7 @@ class ORCLIB_API MemoryStream : public ByteStream
     STDMETHOD_(ULONG64, GetSize)();
     STDMETHOD(SetSize)(ULONG64 ullSize);
 
+    STDMETHOD(Clone)(std::shared_ptr<ByteStream>& clone);
     STDMETHOD(Close)();
 
     HRESULT Duplicate(const MemoryStream& other);

src/OrcLib/ResourceStream.cpp

@@ -74,6 +74,7 @@ HRESULT ResourceStream::OpenForReadOnly(__in const HINSTANCE hInstance, __in WOR
     }
     {
         ScopedLock sl(m_cs);
+        m_hInstance = hInstance;
         std::swap(m_hFileResource, hFileResource);
         std::swap(m_hResource, hResource);
     }
@@ -84,12 +85,9 @@ HRESULT ResourceStream::OpenForReadOnly(__in const HINSTANCE hInstance, __in WOR
 HRESULT ResourceStream::OpenForReadOnly(__in const HINSTANCE hInstance, __in HRSRC hRes)
 {
     HGLOBAL hFileResource = NULL;
-    HRSRC hResource = NULL;
 
     // First find and load the required resource
-    hResource = hRes;
-
-    if ((hFileResource = LoadResource(hInstance, hResource)) == NULL)
+    if ((hFileResource = LoadResource(hInstance, hRes)) == NULL)
     {
         HRESULT hr = HRESULT_FROM_WIN32(GetLastError());
         Log::Debug("Failed LoadResource [{}]", SystemError(hr));
@@ -107,16 +105,17 @@ HRESULT ResourceStream::OpenForReadOnly(__in const HINSTANCE hInstance, __in HRS
 
     DWORD dwSize = 0L;
 
-    if ((dwSize = SizeofResource(hInstance, hResource)) == 0)
+    if ((dwSize = SizeofResource(hInstance, hRes)) == 0)
     {
         HRESULT hr = HRESULT_FROM_WIN32(GetLastError());
         Log::Debug("Failed SizeofResource [{}]", SystemError(hr));
         return hr;
     }
     {
         ScopedLock sl(m_cs);
+        m_hInstance = hInstance;
         std::swap(m_hFileResource, hFileResource);
-        std::swap(m_hResource, hResource);
+        std::swap(m_hResource, hRes);
     }
 
     return MemoryStream::OpenForReadOnly(lpFile, dwSize);
@@ -158,6 +157,30 @@ HRESULT Orc::ResourceStream::OpenForReadOnly(const std::wstring& strResourceSpec
     return S_OK;
 }
 
+STDMETHODIMP Orc::ResourceStream::Clone(std::shared_ptr<ByteStream>& clone)
+{
+    auto new_stream = std::make_shared<ResourceStream>();
+
+    if (IsOpen() == S_FALSE)
+    {
+        clone = new_stream;
+        return S_OK;
+    }
+
+    if (auto hr = new_stream->OpenForReadOnly(m_hInstance, m_hResource); FAILED(hr))
+        return hr;
+
+    ULONG64 ullCurPos = 0LLU;
+    if (auto hr = SetFilePointer(0LL, FILE_CURRENT, &ullCurPos); FAILED(hr))
+        return hr;
+
+    ULONG64 ullDupCurPos = 0LLU;
+    if (auto hr = new_stream->SetFilePointer(ullCurPos, FILE_BEGIN, &ullDupCurPos); FAILED(hr))
+        return hr;
+    clone = new_stream;
+    return S_OK;
+}
+
 HRESULT ResourceStream::Close()
 {
     HGLOBAL hFileResource = NULL;

src/OrcLib/ResourceStream.h

@@ -42,10 +42,12 @@ class ORCLIB_API ResourceStream : public MemoryStream
     STDMETHOD(OpenForReadOnly)(__in const HINSTANCE hInstance, __in HRSRC hRes);
     STDMETHOD(OpenForReadOnly)(__in const std::wstring& strResourceSpec);
 
+    STDMETHOD(Clone)(std::shared_ptr<ByteStream>& clone);
     STDMETHOD(Close)();
 
 protected:
     CriticalSection m_cs;
+    HINSTANCE m_hInstance = NULL;
     HGLOBAL m_hFileResource = NULL;
     HRSRC m_hResource = NULL;
 };