MemProtocol.h

#ifndef MEMPROTOCOL_H
#define MEMPROTOCOL_H

EXTERN_C const GUID CLSID_MemProtocol;

class ATL_NO_VTABLE CMemProtocol :
  public CComObjectRoot,
  public CComCoClass<CMemProtocol, &CLSID_MemProtocol>,
  public IInternetProtocol
{
  const	char	  *m_buffer;
  DWORD		  m_bytes;
  _variant_t	  m_data;
  bool		  m_unaccess;
public:
  CMemProtocol() : m_buffer(0), m_bytes(0), m_unaccess(false) { }
  virtual ~CMemProtocol() {
    if (m_unaccess) ::SafeArrayUnaccessData(V_ARRAY(&m_data));
  }

  DECLARE_NO_REGISTRY()

  DECLARE_PROTECT_FINAL_CONSTRUCT()

  BEGIN_COM_MAP(CMemProtocol)
    COM_INTERFACE_ENTRY(IInternetProtocolRoot)
    COM_INTERFACE_ENTRY(IInternetProtocol)
  END_COM_MAP()

  // IInternetProtocolRoot
  STDMETHOD(Abort)(HRESULT hrReason,DWORD dwOptions) { return E_NOTIMPL; }
  STDMETHOD(Continue)(PROTOCOLDATA *pd) { return E_NOTIMPL; }
  STDMETHOD(Resume)() { return E_NOTIMPL; }
  STDMETHOD(Start)(const wchar_t *url, IInternetProtocolSink *sink,
		   IInternetBindInfo *bi,DWORD flags,HANDLE_PTR dwReserved)
  {
    // check if this an embedded image
    const wchar_t   *col=wcschr(url,L':');
    FB::Doc	*doc;
    if (col) {
      //doc=FB::Doc::LocateDocument(col+1);
		doc = FB::Doc::m_active_doc;
      if (doc) {
	//col=wcschr(col+1,L':');
	  if (col && doc->GetBinary(col+1,m_data)) {
	  if (V_VT(&m_data)==(VT_UI1|VT_ARRAY) && ::SafeArrayGetDim(V_ARRAY(&m_data))==1) 
		{
gotit:
	    m_bytes=V_ARRAY(&m_data)->rgsabound[0].cElements;
	    m_unaccess=true;
	    ::SafeArrayAccessData(V_ARRAY(&m_data),(void**)&m_buffer);
okreport:
	    sink->ReportData(BSCF_DATAFULLYAVAILABLE,1,1);
	    sink->ReportResult(S_OK,0,NULL);
	    return S_OK;
	  } else if (V_VT(&m_data)==VT_BSTR) {
	    m_buffer=(const char *)V_BSTR(&m_data);
	    m_bytes=::SysStringByteLen(V_BSTR(&m_data));
	    m_unaccess=false;
	    sink->ReportProgress(BINDSTATUS_VERIFIEDMIMETYPEAVAILABLE,L"text/html");
	    goto okreport;
	  }
	}
	m_data.Clear();
      }
    }

    // fallback to a builtin image
    HRESULT hr=U::LoadFile(U::GetProgDirFile(_T("imgph.png")),&m_data);
    if (SUCCEEDED(hr))
      goto gotit;

    // or fail
    m_bytes=0;
    return hr;
  }
  STDMETHOD(Suspend)() { return E_NOTIMPL; }
  STDMETHOD(Terminate)(DWORD dwOptions) {
    if (m_unaccess) {
      ::SafeArrayUnaccessData(V_ARRAY(&m_data));
      m_unaccess=false;
    }
    if (V_VT(&m_data)!=VT_EMPTY)
      m_data.Clear();
    m_bytes=0;
    return S_OK;
  }

  // IInternetProtocol
  STDMETHOD(LockRequest)(DWORD dwOptions) { return S_OK; }
  STDMETHOD(Read)(void *pv,ULONG cb,ULONG *cbRead) {
    if (m_bytes==0)
      return S_FALSE;
    if (cb>m_bytes)
      cb=m_bytes;
    memcpy(pv,m_buffer,cb);
    *cbRead=cb;
    m_buffer+=cb;
    m_bytes-=cb;
    return S_OK;
  }
  STDMETHOD(Seek)(LARGE_INTEGER off,DWORD org,ULARGE_INTEGER *newoff) { return E_FAIL; }
  STDMETHOD(UnlockRequest)() { return S_OK; }
};

#endif