gecko-dev/widget/xpwidgets/nsTransferable.cpp

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Mike Pinkerton (pinkerton@netscape.com)
* Dainis Jonitis (Dainis_Jonitis@swh-t.lv)
* Mats Palmgren <matpal@gmail.com>
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
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* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
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* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
/*
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 nsISupportsArrays.
*/
#include "nsTransferable.h"
#include "nsString.h"
#include "nsReadableUtils.h"
#include "nsTArray.h"
#include "nsIFormatConverter.h"
#include "nsIComponentManager.h"
#include "nsCOMPtr.h"
#include "nsXPCOM.h"
#include "nsISupportsPrimitives.h"
#include "nsMemory.h"
#include "nsPrimitiveHelpers.h"
#include "nsXPIDLString.h"
#include "nsDirectoryServiceDefs.h"
#include "nsDirectoryService.h"
#include "nsCRT.h"
#include "nsNetUtil.h"
#include "nsIOutputStream.h"
#include "nsIInputStream.h"
#include "nsIFile.h"
#include "nsAutoPtr.h"
NS_IMPL_ISUPPORTS1(nsTransferable, nsITransferable)
PRUint32 GetDataForFlavor (const nsTArray<DataStruct>& aArray,
const char* aDataFlavor)
{
for (PRUint32 i = 0 ; i < aArray.Length () ; ++i) {
if (aArray[i].GetFlavor().Equals (aDataFlavor))
return i;
}
return aArray.NoIndex;
}
//-------------------------------------------------------------------------
DataStruct::~DataStruct()
{
if (mCacheFileName) nsCRT::free(mCacheFileName);
//nsIFileSpec * cacheFile = GetFileSpec(mCacheFileName);
//cacheFile->Remove();
}
//-------------------------------------------------------------------------
void
DataStruct::SetData ( nsISupports* aData, PRUint32 aDataLen )
{
// Now, check to see if we consider the data to be "too large"
if (aDataLen > kLargeDatasetSize) {
// if so, cache it to disk instead of memory
if ( NS_SUCCEEDED(WriteCache(aData, aDataLen)) )
return;
else
NS_WARNING("Oh no, couldn't write data to the cache file");
}
mData = aData;
mDataLen = aDataLen;
}
//-------------------------------------------------------------------------
void
DataStruct::GetData ( nsISupports** aData, PRUint32 *aDataLen )
{
// check here to see if the data is cached on disk
if ( !mData && mCacheFileName ) {
// if so, read it in and pass it back
// ReadCache creates memory and copies the data into it.
if ( NS_SUCCEEDED(ReadCache(aData, aDataLen)) )
return;
else {
// oh shit, something went horribly wrong here.
NS_WARNING("Oh no, couldn't read data in from the cache file");
*aData = nsnull;
*aDataLen = 0;
return;
}
}
*aData = mData;
if ( mData )
NS_ADDREF(*aData);
*aDataLen = mDataLen;
}
//-------------------------------------------------------------------------
nsIFile*
DataStruct::GetFileSpec(const char * aFileName)
{
nsIFile* cacheFile;
NS_GetSpecialDirectory(NS_OS_TEMP_DIR, &cacheFile);
if (cacheFile == nsnull)
return nsnull;
// if the param aFileName contains a name we should use that
// because the file probably already exists
// otherwise create a unique name
if (!aFileName) {
cacheFile->AppendNative(NS_LITERAL_CSTRING("clipboardcache"));
cacheFile->CreateUnique(nsIFile::NORMAL_FILE_TYPE, 0600);
} else {
cacheFile->AppendNative(nsDependentCString(aFileName));
}
return cacheFile;
}
//-------------------------------------------------------------------------
nsresult
DataStruct::WriteCache(nsISupports* aData, PRUint32 aDataLen)
{
// Get a new path and file to the temp directory
nsCOMPtr<nsIFile> cacheFile ( getter_AddRefs(GetFileSpec(mCacheFileName)) );
if (cacheFile) {
// remember the file name
if (!mCacheFileName) {
nsXPIDLCString fName;
cacheFile->GetNativeLeafName(fName);
mCacheFileName = nsCRT::strdup(fName);
}
// write out the contents of the clipboard
// to the file
//PRUint32 bytes;
nsCOMPtr<nsIOutputStream> outStr;
NS_NewLocalFileOutputStream(getter_AddRefs(outStr),
cacheFile);
if (!outStr) return NS_ERROR_FAILURE;
void* buff = nsnull;
nsPrimitiveHelpers::CreateDataFromPrimitive ( mFlavor.get(), aData, &buff, aDataLen );
if ( buff ) {
PRUint32 ignored;
outStr->Write(reinterpret_cast<char*>(buff), aDataLen, &ignored);
nsMemory::Free(buff);
return NS_OK;
}
}
return NS_ERROR_FAILURE;
}
//-------------------------------------------------------------------------
nsresult
DataStruct::ReadCache(nsISupports** aData, PRUint32* aDataLen)
{
// if we don't have a cache filename we are out of luck
if (!mCacheFileName)
return NS_ERROR_FAILURE;
// get the path and file name
nsCOMPtr<nsIFile> cacheFile ( getter_AddRefs(GetFileSpec(mCacheFileName)) );
bool exists;
if ( cacheFile && NS_SUCCEEDED(cacheFile->Exists(&exists)) && exists ) {
// get the size of the file
PRInt64 fileSize;
PRInt64 max32(LL_INIT(0, 0xFFFFFFFF));
cacheFile->GetFileSize(&fileSize);
if (LL_CMP(fileSize, >, max32))
return NS_ERROR_OUT_OF_MEMORY;
PRUint32 size;
LL_L2UI(size, fileSize);
// create new memory for the large clipboard data
nsAutoArrayPtr<char> data(new char[size]);
if ( !data )
return NS_ERROR_OUT_OF_MEMORY;
// now read it all in
nsCOMPtr<nsIInputStream> inStr;
NS_NewLocalFileInputStream( getter_AddRefs(inStr),
cacheFile);
if (!cacheFile) return NS_ERROR_FAILURE;
nsresult rv = inStr->Read(data, fileSize, aDataLen);
// make sure we got all the data ok
if (NS_SUCCEEDED(rv) && *aDataLen == size) {
nsPrimitiveHelpers::CreatePrimitiveForData ( mFlavor.get(), data, fileSize, aData );
return *aData ? NS_OK : NS_ERROR_FAILURE;
}
// zero the return params
*aData = nsnull;
*aDataLen = 0;
}
return NS_ERROR_FAILURE;
}
//-------------------------------------------------------------------------
//
// Transferable constructor
//
//-------------------------------------------------------------------------
nsTransferable::nsTransferable()
{
}
//-------------------------------------------------------------------------
//
// Transferable destructor
//
//-------------------------------------------------------------------------
nsTransferable::~nsTransferable()
{
}
//
// GetTransferDataFlavors
//
// Returns a copy of the internal list of flavors. This does NOT take into
// account any converter that may be registered. This list consists of
// nsISupportsCString objects so that the flavor list can be accessed from JS.
//
nsresult
nsTransferable::GetTransferDataFlavors(nsISupportsArray ** aDataFlavorList)
{
nsresult rv = NS_NewISupportsArray ( aDataFlavorList );
if (NS_FAILED(rv)) return rv;
for ( PRUint32 i=0; i<mDataArray.Length(); ++i ) {
DataStruct& data = mDataArray.ElementAt(i);
nsCOMPtr<nsISupportsCString> flavorWrapper = do_CreateInstance(NS_SUPPORTS_CSTRING_CONTRACTID);
if ( flavorWrapper ) {
flavorWrapper->SetData ( data.GetFlavor() );
nsCOMPtr<nsISupports> genericWrapper ( do_QueryInterface(flavorWrapper) );
(*aDataFlavorList)->AppendElement( genericWrapper );
}
}
return NS_OK;
}
//
// 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, PRUint32 *aDataLen)
{
NS_ENSURE_ARG_POINTER(aFlavor && aData && aDataLen);
nsresult rv = NS_OK;
nsCOMPtr<nsISupports> savedData;
// first look and see if the data is present in one of the intrinsic flavors
PRUint32 i;
for (i = 0; i < mDataArray.Length(); ++i ) {
DataStruct& data = mDataArray.ElementAt(i);
if ( data.GetFlavor().Equals(aFlavor) ) {
nsCOMPtr<nsISupports> dataBytes;
PRUint32 len;
data.GetData(getter_AddRefs(dataBytes), &len);
if (len == kFlavorHasDataProvider && dataBytes) {
// do we have a data provider?
nsCOMPtr<nsIFlavorDataProvider> dataProvider = do_QueryInterface(dataBytes);
if (dataProvider) {
rv = dataProvider->GetFlavorData(this, aFlavor,
getter_AddRefs(dataBytes), &len);
if (NS_FAILED(rv))
break; // the provider failed. fall into the converter code below.
}
}
if (dataBytes && len > 0) { // XXXmats why is zero length not ok?
*aDataLen = len;
dataBytes.forget(aData);
return NS_OK;
}
savedData = dataBytes; // return this if format converter fails
break;
}
}
bool found = false;
// if not, try using a format converter to get the requested flavor
if ( mFormatConv ) {
for (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;
PRUint32 len;
data.GetData(getter_AddRefs(dataBytes), &len);
if (len == kFlavorHasDataProvider && dataBytes) {
// do we have a data provider?
nsCOMPtr<nsIFlavorDataProvider> dataProvider = do_QueryInterface(dataBytes);
if (dataProvider) {
rv = dataProvider->GetFlavorData(this, aFlavor,
getter_AddRefs(dataBytes), &len);
if (NS_FAILED(rv))
break; // give up
}
}
mFormatConv->Convert(data.GetFlavor().get(), dataBytes, len, aFlavor, aData, aDataLen);
found = true;
break;
}
}
}
// for backward compatibility
if (!found) {
savedData.forget(aData);
*aDataLen = 0;
}
return found ? NS_OK : NS_ERROR_FAILURE;
}
//
// GetAnyTransferData
//
// Returns the data of the first flavor found. Caller is responsible for deleting the
// flavor string.
//
NS_IMETHODIMP
nsTransferable::GetAnyTransferData(char **aFlavor, nsISupports **aData, PRUint32 *aDataLen)
{
NS_ENSURE_ARG_POINTER(aFlavor && aData && aDataLen);
for ( PRUint32 i=0; i < mDataArray.Length(); ++i ) {
DataStruct& data = mDataArray.ElementAt(i);
if (data.IsDataAvailable()) {
*aFlavor = ToNewCString(data.GetFlavor());
data.GetData(aData, aDataLen);
return NS_OK;
}
}
return NS_ERROR_FAILURE;
}
//
// SetTransferData
//
//
//
NS_IMETHODIMP
nsTransferable::SetTransferData(const char *aFlavor, nsISupports *aData, PRUint32 aDataLen)
{
NS_ENSURE_ARG(aFlavor);
// first check our intrinsic flavors to see if one has been registered.
PRUint32 i = 0;
for (i = 0; i < mDataArray.Length(); ++i) {
DataStruct& data = mDataArray.ElementAt(i);
if ( data.GetFlavor().Equals(aFlavor) ) {
data.SetData ( aData, aDataLen );
return NS_OK;
}
}
// if not, try using a format converter to find a flavor to put the data in
if ( mFormatConv ) {
for (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;
PRUint32 ConvertedLen;
mFormatConv->Convert(aFlavor, aData, aDataLen, data.GetFlavor().get(), getter_AddRefs(ConvertedData), &ConvertedLen);
data.SetData(ConvertedData, ConvertedLen);
return NS_OK;
}
}
}
// Can't set data neither directly nor through converter. Just add this flavor and try again
nsresult result = NS_ERROR_FAILURE;
if ( NS_SUCCEEDED(AddDataFlavor(aFlavor)) )
result = SetTransferData (aFlavor, aData, aDataLen);
return result;
}
//
// AddDataFlavor
//
// Adds a data flavor to our list with no data. Error if it already exists.
//
NS_IMETHODIMP
nsTransferable::AddDataFlavor(const char *aDataFlavor)
{
if (GetDataForFlavor (mDataArray, aDataFlavor) != mDataArray.NoIndex)
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)
{
PRUint32 idx;
if ((idx = GetDataForFlavor(mDataArray, aDataFlavor)) != mDataArray.NoIndex) {
mDataArray.RemoveElementAt (idx);
return NS_OK;
}
return NS_ERROR_FAILURE;
}
/**
*
*
*/
NS_IMETHODIMP
nsTransferable::IsLargeDataSet(bool *_retval)
{
NS_ENSURE_ARG_POINTER(_retval);
*_retval = false;
return NS_OK;
}
/**
*
*
*/
NS_IMETHODIMP nsTransferable::SetConverter(nsIFormatConverter * aConverter)
{
mFormatConv = aConverter;
return NS_OK;
}
/**
*
*
*/
NS_IMETHODIMP nsTransferable::GetConverter(nsIFormatConverter * *aConverter)
{
NS_ENSURE_ARG_POINTER(aConverter);
*aConverter = mFormatConv;
NS_IF_ADDREF(*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(nsISupportsArray **_retval)
{
NS_ENSURE_ARG_POINTER(_retval);
// 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(_retval); // addrefs
nsCOMPtr<nsIFormatConverter> converter;
GetConverter(getter_AddRefs(converter));
if ( converter ) {
nsCOMPtr<nsISupportsArray> convertedList;
converter->GetInputDataFlavors(getter_AddRefs(convertedList));
if ( convertedList ) {
PRUint32 importListLen;
convertedList->Count(&importListLen);
for ( PRUint32 i=0; i < importListLen; ++i ) {
nsCOMPtr<nsISupports> genericFlavor;
convertedList->GetElementAt ( i, getter_AddRefs(genericFlavor) );
nsCOMPtr<nsISupportsCString> flavorWrapper ( do_QueryInterface (genericFlavor) );
nsCAutoString flavorStr;
flavorWrapper->GetData( flavorStr );
if (GetDataForFlavor (mDataArray, flavorStr.get())
== mDataArray.NoIndex) // Don't append if already in intrinsic list
(*_retval)->AppendElement (genericFlavor);
} // foreach flavor that can be converted to
}
} // if a converter exists
return NS_OK;
} // FlavorsTransferableCanImport
//
// FlavorsTransferableCanExport
//
// Computes a list of flavors that the transferable can export, either through
// intrinsic knowledge or output data converters.
//
NS_IMETHODIMP
nsTransferable::FlavorsTransferableCanExport(nsISupportsArray **_retval)
{
NS_ENSURE_ARG_POINTER(_retval);
// 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(_retval); // addrefs
nsCOMPtr<nsIFormatConverter> converter;
GetConverter(getter_AddRefs(converter));
if ( converter ) {
nsCOMPtr<nsISupportsArray> convertedList;
converter->GetOutputDataFlavors(getter_AddRefs(convertedList));
if ( convertedList ) {
PRUint32 importListLen;
convertedList->Count(&importListLen);
for ( PRUint32 i=0; i < importListLen; ++i ) {
nsCOMPtr<nsISupports> genericFlavor;
convertedList->GetElementAt ( i, getter_AddRefs(genericFlavor) );
nsCOMPtr<nsISupportsCString> flavorWrapper ( do_QueryInterface (genericFlavor) );
nsCAutoString flavorStr;
flavorWrapper->GetData( flavorStr );
if (GetDataForFlavor (mDataArray, flavorStr.get())
== mDataArray.NoIndex) // Don't append if already in intrinsic list
(*_retval)->AppendElement (genericFlavor);
} // foreach flavor that can be converted to
}
} // if a converter exists
return NS_OK;
} // FlavorsTransferableCanExport