gecko-dev/widget/nsTransferable.h
Tom Schuster 0959f0508c Bug 1499821 - Introduce the FindDataFlavor helper function to nsTransferable. r=froydnj
This combines some of your ideas from D8074, in which I think is quite a big improvement to the overall code.

The code for nsTransferable::GetTransferData, especially nsIFlavorDataProvider is a bit wonky, because I tried to preserve the current behavior.

Differential Revision: https://phabricator.services.mozilla.com/D9599

--HG--
extra : moz-landing-system : lando
2018-10-25 10:04:43 +00:00

95 lines
2.4 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef nsTransferable_h__
#define nsTransferable_h__
#include "nsIFormatConverter.h"
#include "nsITransferable.h"
#include "nsCOMPtr.h"
#include "nsString.h"
#include "nsTArray.h"
#include "nsIPrincipal.h"
#include "prio.h"
#include "mozilla/Maybe.h"
class nsIMutableArray;
//
// DataStruct
//
// Holds a flavor (a mime type) that describes the data and the associated data.
//
struct DataStruct
{
explicit DataStruct ( const char* aFlavor )
: mDataLen(0), mCacheFD(nullptr), mFlavor(aFlavor) { }
DataStruct(DataStruct&& aRHS);
~DataStruct();
const nsCString& GetFlavor() const { return mFlavor; }
void SetData( nsISupports* inData, uint32_t inDataLen, bool aIsPrivateData );
void GetData( nsISupports** outData, uint32_t *outDataLen );
bool IsDataAvailable() const { return mData ? mDataLen > 0 : mCacheFD != nullptr; }
protected:
enum {
// The size of data over which we write the data to disk rather than
// keep it around in memory.
kLargeDatasetSize = 1000000 // 1 million bytes
};
nsresult WriteCache(nsISupports* aData, uint32_t aDataLen );
nsresult ReadCache(nsISupports** aData, uint32_t* aDataLen );
// mData + mDataLen OR mCacheFD should be used, not both.
nsCOMPtr<nsISupports> mData; // OWNER - some varient of primitive wrapper
uint32_t mDataLen;
PRFileDesc* mCacheFD;
const nsCString mFlavor;
private:
DataStruct(const DataStruct&) = delete;
DataStruct& operator=(const DataStruct&) = delete;
};
/**
* XP Transferable wrapper
*/
class nsTransferable : public nsITransferable
{
public:
nsTransferable();
// nsISupports
NS_DECL_ISUPPORTS
NS_DECL_NSITRANSFERABLE
protected:
virtual ~nsTransferable();
// Get flavors w/out converter
void GetTransferDataFlavors(nsTArray<nsCString>& aFlavors);
// Find index for data with the matching flavor in mDataArray.
mozilla::Maybe<size_t> FindDataFlavor(const char* aFlavor);
nsTArray<DataStruct> mDataArray;
nsCOMPtr<nsIFormatConverter> mFormatConv;
bool mPrivateData;
nsCOMPtr<nsIPrincipal> mRequestingPrincipal;
nsContentPolicyType mContentPolicyType;
#if DEBUG
bool mInitialized;
#endif
};
#endif // nsTransferable_h__