cef/libcef_dll/ctocpp/ctocpp.h

123 lines
3.3 KiB
C++

// Copyright (c) 2009 The Chromium Embedded Framework Authors. All rights
// reserved. Use of this source code is governed by a BSD-style license that
// can be found in the LICENSE file.
#ifndef _CTOCPP_H
#define _CTOCPP_H
#include "include/cef.h"
#include "include/cef_capi.h"
#include "libcef_dll/cef_logging.h"
// Wrap a C structure with a C++ class. This is used when the implementation
// exists on the other side of the DLL boundary but will have methods called on
// this side of the DLL boundary.
template <class ClassName, class BaseName, class StructName>
class CefCToCpp : public BaseName
{
public:
// Use this method to create a wrapper class instance for a structure
// received from the other side.
static CefRefPtr<BaseName> Wrap(StructName* s)
{
if (!s)
return NULL;
// Wrap their structure with the CefCToCpp object.
ClassName* wrapper = new ClassName(s);
// Put the wrapper object in a smart pointer.
CefRefPtr<BaseName> wrapperPtr(wrapper);
// Release the reference that was added to the CefCppToC wrapper object on
// the other side before their structure was passed to us.
wrapper->UnderlyingRelease();
// Return the smart pointer.
return wrapperPtr;
}
// Use this method to retrieve the underlying structure from a wrapper class
// instance for return back to the other side.
static StructName* Unwrap(CefRefPtr<BaseName> c)
{
if (!c.get())
return NULL;
// Cast the object to our wrapper class type.
ClassName* wrapper = static_cast<ClassName*>(c.get());
// Add a reference to the CefCppToC wrapper object on the other side that
// will be released once the structure is received.
wrapper->UnderlyingAddRef();
// Return their original structure.
return wrapper->GetStruct();
}
CefCToCpp(StructName* str)
: struct_(str)
{
DCHECK(str);
#ifndef NDEBUG
CefAtomicIncrement(&DebugObjCt);
#endif
}
virtual ~CefCToCpp()
{
#ifndef NDEBUG
CefAtomicDecrement(&DebugObjCt);
#endif
}
// If returning the structure across the DLL boundary you should call
// UnderlyingAddRef() on this wrapping CefCToCpp object. On the other side of
// the DLL boundary, call Release() on the CefCppToC object.
StructName* GetStruct() { return struct_; }
// CefBase methods increment/decrement reference counts on both this object
// and the underlying wrapped structure.
int AddRef()
{
UnderlyingAddRef();
return refct_.AddRef();
}
int Release()
{
UnderlyingRelease();
int retval = refct_.Release();
if (retval == 0)
delete this;
return retval;
}
int GetRefCt() { return refct_.GetRefCt(); }
// Increment/decrement reference counts on only the underlying class.
int UnderlyingAddRef()
{
if(!struct_->base.add_ref)
return 0;
return struct_->base.add_ref(&struct_->base);
}
int UnderlyingRelease()
{
if(!struct_->base.release)
return 0;
return struct_->base.release(&struct_->base);
}
int UnderlyingGetRefCt()
{
if(!struct_->base.get_refct)
return 0;
return struct_->base.get_refct(&struct_->base);
}
#ifndef NDEBUG
// Simple tracking of allocated objects.
static long DebugObjCt;
#endif
protected:
CefRefCount refct_;
StructName* struct_;
};
#endif // _CTOCPP_H