widget/nsTransferable.cpp
author Botond Ballo <botond@mozilla.com>
Thu, 25 Apr 2019 14:33:17 +0000
changeset 530341 4f70b98aa8705b6906b6bd2a3de66d374addb177
parent 505383 6f3709b3878117466168c40affa7bca0b60cf75b
permissions -rw-r--r--
Bug 1546139 - Restore the call to AdjustFixedOrStickyLayer() for layers fixed to the RCD-RSF. r=kats This call served two purposes: (1) scroll the fixed layer by the eVisual transform, and (2) adjust it by the fixed margins. The first purpose is now served by applying the eVisual transform to the async zoom container, but we still need the call for the second purpose. Differential Revision: https://phabricator.services.mozilla.com/D28735

/* -*- 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/. */

/*
Notes to self:

- at some point, strings will be accessible from JS, so we won't have to wrap
   flavors in an nsISupportsCString. Until then, we're kinda stuck with
   this crappy API of nsIArrays.

*/

#include "nsTransferable.h"
#include "nsAnonymousTemporaryFile.h"
#include "nsArray.h"
#include "nsArrayUtils.h"
#include "nsString.h"
#include "nsReadableUtils.h"
#include "nsTArray.h"
#include "nsIFormatConverter.h"
#include "nsIContentPolicy.h"
#include "nsIComponentManager.h"
#include "nsCOMPtr.h"
#include "nsXPCOM.h"
#include "nsISupportsPrimitives.h"
#include "nsMemory.h"
#include "nsPrimitiveHelpers.h"
#include "nsDirectoryServiceDefs.h"
#include "nsDirectoryService.h"
#include "nsCRT.h"
#include "nsNetUtil.h"
#include "nsIOutputStream.h"
#include "nsIInputStream.h"
#include "nsILoadContext.h"
#include "nsXULAppAPI.h"
#include "mozilla/UniquePtr.h"

using namespace mozilla;

NS_IMPL_ISUPPORTS(nsTransferable, nsITransferable)

DataStruct::DataStruct(DataStruct&& aRHS)
    : mData(aRHS.mData.forget()),
      mCacheFD(aRHS.mCacheFD),
      mFlavor(aRHS.mFlavor) {
  aRHS.mCacheFD = nullptr;
}

//-------------------------------------------------------------------------
DataStruct::~DataStruct() {
  if (mCacheFD) {
    PR_Close(mCacheFD);
  }
}

//-------------------------------------------------------------------------

void DataStruct::SetData(nsISupports* aData, bool aIsPrivateData) {
  // Now, check to see if we consider the data to be "too large"
  // as well as ensuring that private browsing mode is disabled.
  // File IO is not allowed in content processes.
  if (!aIsPrivateData && XRE_IsParentProcess()) {
    void* data = nullptr;
    uint32_t dataLen = 0;
    nsPrimitiveHelpers::CreateDataFromPrimitive(mFlavor, aData, &data,
                                                &dataLen);

    if (dataLen > kLargeDatasetSize) {
      // Too large, cache it to disk instead of memory.
      if (NS_SUCCEEDED(WriteCache(data, dataLen))) {
        free(data);
        // Clear previously set small data.
        mData = nullptr;
        return;
      }

      NS_WARNING("Oh no, couldn't write data to the cache file");
    }

    free(data);
  }

  if (mCacheFD) {
    // Clear previously set big data.
    PR_Close(mCacheFD);
    mCacheFD = nullptr;
  }

  mData = aData;
}

//-------------------------------------------------------------------------
void DataStruct::GetData(nsISupports** aData) {
  // check here to see if the data is cached on disk
  if (mCacheFD) {
    // if so, read it in and pass it back
    // ReadCache creates memory and copies the data into it.
    if (NS_SUCCEEDED(ReadCache(aData))) {
      return;
    }

    // oh shit, something went horribly wrong here.
    NS_WARNING("Oh no, couldn't read data in from the cache file");
    *aData = nullptr;
    PR_Close(mCacheFD);
    mCacheFD = nullptr;
    return;
  }

  nsCOMPtr<nsISupports> data = mData;
  data.forget(aData);
}

//-------------------------------------------------------------------------
nsresult DataStruct::WriteCache(void* aData, uint32_t aDataLen) {
  MOZ_ASSERT(aData && aDataLen);
  MOZ_ASSERT(aDataLen <= uint32_t(std::numeric_limits<int32_t>::max()),
             "too large size for PR_Write");

  nsresult rv;
  if (!mCacheFD) {
    rv = NS_OpenAnonymousTemporaryFile(&mCacheFD);
    if (NS_FAILED(rv)) {
      return NS_ERROR_FAILURE;
    }
  } else if (PR_Seek64(mCacheFD, 0, PR_SEEK_SET) == -1) {
    return NS_ERROR_FAILURE;
  }

  // Write out the contents of the clipboard to the file.
  int32_t written = PR_Write(mCacheFD, aData, aDataLen);
  if (written == int32_t(aDataLen)) {
    return NS_OK;
  }

  PR_Close(mCacheFD);
  mCacheFD = nullptr;
  return NS_ERROR_FAILURE;
}

//-------------------------------------------------------------------------
nsresult DataStruct::ReadCache(nsISupports** aData) {
  if (!mCacheFD) {
    return NS_ERROR_FAILURE;
  }

  PRFileInfo fileInfo;
  if (PR_GetOpenFileInfo(mCacheFD, &fileInfo) != PR_SUCCESS) {
    return NS_ERROR_FAILURE;
  }
  if (PR_Seek64(mCacheFD, 0, PR_SEEK_SET) == -1) {
    return NS_ERROR_FAILURE;
  }
  uint32_t fileSize = fileInfo.size;

  auto data = MakeUnique<char[]>(fileSize);
  if (!data) {
    return NS_ERROR_OUT_OF_MEMORY;
  }

  uint32_t actual = PR_Read(mCacheFD, data.get(), fileSize);
  if (actual != fileSize) {
    return NS_ERROR_FAILURE;
  }

  nsPrimitiveHelpers::CreatePrimitiveForData(mFlavor, data.get(), fileSize,
                                             aData);
  return NS_OK;
}

//-------------------------------------------------------------------------
//
// Transferable constructor
//
//-------------------------------------------------------------------------
nsTransferable::nsTransferable()
    : mPrivateData(false),
      mContentPolicyType(nsIContentPolicy::TYPE_OTHER)
#ifdef DEBUG
      ,
      mInitialized(false)
#endif
{
}

//-------------------------------------------------------------------------
//
// Transferable destructor
//
//-------------------------------------------------------------------------
nsTransferable::~nsTransferable() {}

NS_IMETHODIMP
nsTransferable::Init(nsILoadContext* aContext) {
  MOZ_ASSERT(!mInitialized);

  if (aContext) {
    mPrivateData = aContext->UsePrivateBrowsing();
  }
#ifdef DEBUG
  mInitialized = true;
#endif
  return NS_OK;
}

//
// GetTransferDataFlavors
//
// Returns a copy of the internal list of flavors. This does NOT take into
// account any converter that may be registered.
//
void nsTransferable::GetTransferDataFlavors(nsTArray<nsCString>& aFlavors) {
  MOZ_ASSERT(mInitialized);

  for (size_t i = 0; i < mDataArray.Length(); ++i) {
    DataStruct& data = mDataArray.ElementAt(i);
    aFlavors.AppendElement(data.GetFlavor());
  }
}

Maybe<size_t> nsTransferable::FindDataFlavor(const char* aFlavor) {
  nsDependentCString flavor(aFlavor);

  for (size_t i = 0; i < mDataArray.Length(); ++i) {
    if (mDataArray[i].GetFlavor().Equals(flavor)) {
      return Some(i);
    }
  }

  return Nothing();
}

//
// GetTransferData
//
// Returns the data of the requested flavor, obtained from either having the
// data on hand or using a converter to get it. The data is wrapped in a
// nsISupports primitive so that it is accessible from JS.
//
NS_IMETHODIMP
nsTransferable::GetTransferData(const char* aFlavor, nsISupports** aData) {
  MOZ_ASSERT(mInitialized);

  *aData = nullptr;

  nsresult rv = NS_OK;

  // First look and see if the data is present in one of the intrinsic flavors.
  if (Maybe<size_t> index = FindDataFlavor(aFlavor)) {
    nsCOMPtr<nsISupports> dataBytes;
    mDataArray[index.value()].GetData(getter_AddRefs(dataBytes));

    // Do we have a (lazy) data provider?
    if (nsCOMPtr<nsIFlavorDataProvider> dataProvider =
            do_QueryInterface(dataBytes)) {
      rv =
          dataProvider->GetFlavorData(this, aFlavor, getter_AddRefs(dataBytes));
      if (NS_FAILED(rv)) {
        dataBytes = nullptr;
        // The provider failed, fall into the converter code below.
      }
    }

    if (dataBytes) {
      dataBytes.forget(aData);
      return NS_OK;
    }

    // Empty data
  }

  // If not, try using a format converter to get the requested flavor.
  if (mFormatConv) {
    for (size_t i = 0; i < mDataArray.Length(); ++i) {
      DataStruct& data = mDataArray.ElementAt(i);
      bool canConvert = false;
      mFormatConv->CanConvert(data.GetFlavor().get(), aFlavor, &canConvert);
      if (canConvert) {
        nsCOMPtr<nsISupports> dataBytes;
        data.GetData(getter_AddRefs(dataBytes));

        // Do we have a (lazy) data provider?
        if (nsCOMPtr<nsIFlavorDataProvider> dataProvider =
                do_QueryInterface(dataBytes)) {
          rv = dataProvider->GetFlavorData(this, aFlavor,
                                           getter_AddRefs(dataBytes));
          if (NS_FAILED(rv)) {
            // Give up.
            return rv;
          }
        }

        return mFormatConv->Convert(data.GetFlavor().get(), dataBytes, aFlavor,
                                    aData);
      }
    }
  }

  return NS_ERROR_FAILURE;
}

//
// GetAnyTransferData
//
// Returns the data of the first flavor found. Caller is responsible for
// deleting the flavor string.
//
NS_IMETHODIMP
nsTransferable::GetAnyTransferData(nsACString& aFlavor, nsISupports** aData) {
  MOZ_ASSERT(mInitialized);

  for (size_t i = 0; i < mDataArray.Length(); ++i) {
    DataStruct& data = mDataArray.ElementAt(i);
    if (data.IsDataAvailable()) {
      aFlavor.Assign(data.GetFlavor());
      data.GetData(aData);
      return NS_OK;
    }
  }

  return NS_ERROR_FAILURE;
}

//
// SetTransferData
//
//
//
NS_IMETHODIMP
nsTransferable::SetTransferData(const char* aFlavor, nsISupports* aData) {
  MOZ_ASSERT(mInitialized);

  // first check our intrinsic flavors to see if one has been registered.
  if (Maybe<size_t> index = FindDataFlavor(aFlavor)) {
    DataStruct& data = mDataArray.ElementAt(index.value());
    data.SetData(aData, mPrivateData);
    return NS_OK;
  }

  // if not, try using a format converter to find a flavor to put the data in
  if (mFormatConv) {
    for (size_t i = 0; i < mDataArray.Length(); ++i) {
      DataStruct& data = mDataArray.ElementAt(i);
      bool canConvert = false;
      mFormatConv->CanConvert(aFlavor, data.GetFlavor().get(), &canConvert);

      if (canConvert) {
        nsCOMPtr<nsISupports> ConvertedData;
        mFormatConv->Convert(aFlavor, aData, data.GetFlavor().get(),
                             getter_AddRefs(ConvertedData));
        data.SetData(ConvertedData, mPrivateData);
        return NS_OK;
      }
    }
  }

  // Can't set data neither directly nor through converter. Just add this flavor
  // and try again
  if (NS_SUCCEEDED(AddDataFlavor(aFlavor))) {
    return SetTransferData(aFlavor, aData);
  }

  return NS_ERROR_FAILURE;
}

//
// AddDataFlavor
//
// Adds a data flavor to our list with no data. Error if it already exists.
//
NS_IMETHODIMP
nsTransferable::AddDataFlavor(const char* aDataFlavor) {
  MOZ_ASSERT(mInitialized);

  if (FindDataFlavor(aDataFlavor).isSome()) {
    return NS_ERROR_FAILURE;
  }

  // Create a new "slot" for the data
  mDataArray.AppendElement(DataStruct(aDataFlavor));
  return NS_OK;
}

//
// RemoveDataFlavor
//
// Removes a data flavor (and causes the data to be destroyed). Error if
// the requested flavor is not present.
//
NS_IMETHODIMP
nsTransferable::RemoveDataFlavor(const char* aDataFlavor) {
  MOZ_ASSERT(mInitialized);

  if (Maybe<size_t> index = FindDataFlavor(aDataFlavor)) {
    mDataArray.RemoveElementAt(index.value());
    return NS_OK;
  }

  return NS_ERROR_FAILURE;
}

NS_IMETHODIMP
nsTransferable::SetConverter(nsIFormatConverter* aConverter) {
  MOZ_ASSERT(mInitialized);

  mFormatConv = aConverter;
  return NS_OK;
}

NS_IMETHODIMP
nsTransferable::GetConverter(nsIFormatConverter** aConverter) {
  MOZ_ASSERT(mInitialized);

  nsCOMPtr<nsIFormatConverter> converter = mFormatConv;
  converter.forget(aConverter);
  return NS_OK;
}

//
// FlavorsTransferableCanImport
//
// Computes a list of flavors that the transferable can accept into it, either
// through intrinsic knowledge or input data converters.
//
NS_IMETHODIMP
nsTransferable::FlavorsTransferableCanImport(nsTArray<nsCString>& aFlavors) {
  MOZ_ASSERT(mInitialized);

  // Get the flavor list, and on to the end of it, append the list of flavors we
  // can also get to through a converter. This is so that we can just walk the
  // list in one go, looking for the desired flavor.
  GetTransferDataFlavors(aFlavors);

  if (mFormatConv) {
    nsTArray<nsCString> convertedList;
    mFormatConv->GetInputDataFlavors(convertedList);

    for (uint32_t i = 0; i < convertedList.Length(); ++i) {
      nsCString& flavorStr = convertedList[i];

      // Don't append if already in intrinsic list
      if (!aFlavors.Contains(flavorStr)) {
        aFlavors.AppendElement(flavorStr);
      }
    }
  }

  return NS_OK;
}

//
// FlavorsTransferableCanExport
//
// Computes a list of flavors that the transferable can export, either through
// intrinsic knowledge or output data converters.
//
NS_IMETHODIMP
nsTransferable::FlavorsTransferableCanExport(nsTArray<nsCString>& aFlavors) {
  MOZ_ASSERT(mInitialized);

  // Get the flavor list, and on to the end of it, append the list of flavors we
  // can also get to through a converter. This is so that we can just walk the
  // list in one go, looking for the desired flavor.
  GetTransferDataFlavors(aFlavors);

  if (mFormatConv) {
    nsTArray<nsCString> convertedList;
    mFormatConv->GetOutputDataFlavors(convertedList);

    for (uint32_t i = 0; i < convertedList.Length(); ++i) {
      nsCString& flavorStr = convertedList[i];

      // Don't append if already in intrinsic list
      if (!aFlavors.Contains(flavorStr)) {
        aFlavors.AppendElement(flavorStr);
      }
    }
  }

  return NS_OK;
}

bool nsTransferable::GetIsPrivateData() {
  MOZ_ASSERT(mInitialized);

  return mPrivateData;
}

void nsTransferable::SetIsPrivateData(bool aIsPrivateData) {
  MOZ_ASSERT(mInitialized);

  mPrivateData = aIsPrivateData;
}

nsIPrincipal* nsTransferable::GetRequestingPrincipal() {
  MOZ_ASSERT(mInitialized);

  return mRequestingPrincipal;
}

void nsTransferable::SetRequestingPrincipal(
    nsIPrincipal* aRequestingPrincipal) {
  MOZ_ASSERT(mInitialized);

  mRequestingPrincipal = aRequestingPrincipal;
}

nsContentPolicyType nsTransferable::GetContentPolicyType() {
  MOZ_ASSERT(mInitialized);

  return mContentPolicyType;
}

void nsTransferable::SetContentPolicyType(
    nsContentPolicyType aContentPolicyType) {
  MOZ_ASSERT(mInitialized);

  mContentPolicyType = aContentPolicyType;
}