already_AddRefed<nsITransferable>
DataTransfer::GetTransferable(uint32_t aIndex, nsILoadContext* aLoadContext)
{
if (aIndex >= mItems.Length()) {
return nullptr;
}
nsTArray<TransferItem>& item = mItems[aIndex];
uint32_t count = item.Length();
if (!count) {
return nullptr;
}
nsCOMPtr<nsITransferable> transferable =
do_CreateInstance("@mozilla.org/widget/transferable;1");
if (!transferable) {
return nullptr;
}
transferable->Init(aLoadContext);
nsCOMPtr<nsIStorageStream> storageStream;
nsCOMPtr<nsIBinaryOutputStream> stream;
bool added = false;
bool handlingCustomFormats = true;
uint32_t totalCustomLength = 0;
const char* knownFormats[] = { kTextMime, kHTMLMime, kNativeHTMLMime, kRTFMime,
kURLMime, kURLDataMime, kURLDescriptionMime, kURLPrivateMime,
kPNGImageMime, kJPEGImageMime, kGIFImageMime, kNativeImageMime,
kFileMime, kFilePromiseMime, kFilePromiseDirectoryMime,
kMozTextInternal, kHTMLContext, kHTMLInfo };
/*
* Two passes are made here to iterate over all of the types. First, look for
* any types that are not in the list of known types. For this pass, handlingCustomFormats
* will be true. Data that corresponds to unknown types will be pulled out and
* inserted into a single type (kCustomTypesMime) by writing the data into a stream.
*
* The second pass will iterate over the formats looking for known types. These are
* added as is. The unknown types are all then inserted as a single type (kCustomTypesMime)
* in the same position of the first custom type. This model is used to maintain the
* format order as best as possible.
*
* The format of the kCustomTypesMime type is one or more of the following stored sequentially:
* <32-bit> type (only none or string is supported)
* <32-bit> length of format
* <wide string> format
* <32-bit> length of data
* <wide string> data
* A type of eCustomClipboardTypeId_None ends the list, without any following data.
*/
do {
for (uint32_t f = 0; f < count; f++) {
const TransferItem& formatitem = item[f];
if (!formatitem.mData) { // skip empty items
continue;
}
// If the data is of one of the well-known formats, use it directly.
bool isCustomFormat = true;
for (uint32_t f = 0; f < ArrayLength(knownFormats); f++) {
if (formatitem.mFormat.EqualsASCII(knownFormats[f])) {
isCustomFormat = false;
break;
}
}
uint32_t lengthInBytes;
nsCOMPtr<nsISupports> convertedData;
if (handlingCustomFormats) {
if (!ConvertFromVariant(formatitem.mData, getter_AddRefs(convertedData), &lengthInBytes)) {
continue;
}
// When handling custom types, add the data to the stream if this is a
// custom type.
if (isCustomFormat) {
// If it isn't a string, just ignore it. The dataTransfer is cached in the
// drag sesion during drag-and-drop, so non-strings will be available when
// dragging locally.
nsCOMPtr<nsISupportsString> str(do_QueryInterface(convertedData));
if (str) {
nsAutoString data;
str->GetData(data);
if (!stream) {
// Create a storage stream to write to.
NS_NewStorageStream(1024, UINT32_MAX, getter_AddRefs(storageStream));
nsCOMPtr<nsIOutputStream> outputStream;
storageStream->GetOutputStream(0, getter_AddRefs(outputStream));
stream = do_CreateInstance("@mozilla.org/binaryoutputstream;1");
stream->SetOutputStream(outputStream);
}
int32_t formatLength = formatitem.mFormat.Length() * sizeof(nsString::char_type);
stream->Write32(eCustomClipboardTypeId_String);
stream->Write32(formatLength);
stream->WriteBytes((const char *)formatitem.mFormat.get(), formatLength);
stream->Write32(lengthInBytes);
stream->WriteBytes((const char *)data.get(), lengthInBytes);
// The total size of the stream is the format length, the data length,
// two integers to hold the lengths and one integer for the string flag.
totalCustomLength += formatLength + lengthInBytes + (sizeof(uint32_t) * 3);
}
}
} else if (isCustomFormat && stream) {
// This is the second pass of the loop (handlingCustomFormats is false).
// When encountering the first custom format, append all of the stream
// at this position.
// Write out a terminator.
totalCustomLength += sizeof(uint32_t);
stream->Write32(eCustomClipboardTypeId_None);
nsCOMPtr<nsIInputStream> inputStream;
storageStream->NewInputStream(0, getter_AddRefs(inputStream));
RefPtr<nsStringBuffer> stringBuffer = nsStringBuffer::Alloc(totalCustomLength + 1);
// Read the data from the string and add a null-terminator as ToString needs it.
uint32_t amountRead;
inputStream->Read(static_cast<char*>(stringBuffer->Data()), totalCustomLength, &amountRead);
static_cast<char*>(stringBuffer->Data())[amountRead] = 0;
nsCString str;
stringBuffer->ToString(totalCustomLength, str);
nsCOMPtr<nsISupportsCString> strSupports(do_CreateInstance(NS_SUPPORTS_CSTRING_CONTRACTID));
strSupports->SetData(str);
nsresult rv = transferable->SetTransferData(kCustomTypesMime, strSupports, totalCustomLength);
if (NS_FAILED(rv)) {
return nullptr;
}
added = true;
// Clear the stream so it doesn't get used again.
stream = nullptr;
} else {
// This is the second pass of the loop and a known type is encountered.
// Add it as is.
if (!ConvertFromVariant(formatitem.mData, getter_AddRefs(convertedData), &lengthInBytes)) {
continue;
}
// The underlying drag code uses text/unicode, so use that instead of text/plain
const char* format;
NS_ConvertUTF16toUTF8 utf8format(formatitem.mFormat);
if (utf8format.EqualsLiteral(kTextMime)) {
format = kUnicodeMime;
} else {
format = utf8format.get();
}
// If a converter is set for a format, set the converter for the
// transferable and don't add the item
nsCOMPtr<nsIFormatConverter> converter = do_QueryInterface(convertedData);
if (converter) {
transferable->AddDataFlavor(format);
transferable->SetConverter(converter);
continue;
}
nsresult rv = transferable->SetTransferData(format, convertedData, lengthInBytes);
if (NS_FAILED(rv)) {
return nullptr;
}
added = true;
}
}
handlingCustomFormats = !handlingCustomFormats;
} while (!handlingCustomFormats);
// only return the transferable if data was successfully added to it
if (added) {
return transferable.forget();
}
return nullptr;
}
bool
DataTransfer::ConvertFromVariant(nsIVariant* aVariant,
nsISupports** aSupports,
uint32_t* aLength)
{
*aSupports = nullptr;
*aLength = 0;
uint16_t type;
aVariant->GetDataType(&type);
if (type == nsIDataType::VTYPE_INTERFACE ||
type == nsIDataType::VTYPE_INTERFACE_IS) {
nsCOMPtr<nsISupports> data;
if (NS_FAILED(aVariant->GetAsISupports(getter_AddRefs(data))))
return false;
nsCOMPtr<nsIFlavorDataProvider> fdp = do_QueryInterface(data);
if (fdp) {
// for flavour data providers, use kFlavorHasDataProvider (which has the
// value 0) as the length.
NS_ADDREF(*aSupports = fdp);
*aLength = nsITransferable::kFlavorHasDataProvider;
}
else {
// wrap the item in an nsISupportsInterfacePointer
nsCOMPtr<nsISupportsInterfacePointer> ptrSupports =
do_CreateInstance(NS_SUPPORTS_INTERFACE_POINTER_CONTRACTID);
if (!ptrSupports)
return false;
ptrSupports->SetData(data);
NS_ADDREF(*aSupports = ptrSupports);
*aLength = sizeof(nsISupportsInterfacePointer *);
}
return true;
}
char16_t* chrs;
uint32_t len = 0;
nsresult rv = aVariant->GetAsWStringWithSize(&len, &chrs);
if (NS_FAILED(rv))
return false;
nsAutoString str;
str.Adopt(chrs, len);
nsCOMPtr<nsISupportsString>
strSupports(do_CreateInstance(NS_SUPPORTS_STRING_CONTRACTID));
if (!strSupports)
return false;
strSupports->SetData(str);
*aSupports = strSupports;
NS_ADDREF(*aSupports);
// each character is two bytes
*aLength = str.Length() << 1;
return true;
}
already_AddRefed<nsITransferable>
DataTransfer::GetTransferable(uint32_t aIndex, nsILoadContext* aLoadContext)
{
if (aIndex >= MozItemCount()) {
return nullptr;
}
const nsTArray<RefPtr<DataTransferItem>>& item = *mItems->MozItemsAt(aIndex);
uint32_t count = item.Length();
if (!count) {
return nullptr;
}
nsCOMPtr<nsITransferable> transferable =
do_CreateInstance("@mozilla.org/widget/transferable;1");
if (!transferable) {
return nullptr;
}
transferable->Init(aLoadContext);
nsCOMPtr<nsIStorageStream> storageStream;
nsCOMPtr<nsIBinaryOutputStream> stream;
bool added = false;
bool handlingCustomFormats = true;
// When writing the custom data, we need to ensure that there is sufficient
// space for a (uint32_t) data ending type, and the null byte character at
// the end of the nsCString. We claim that space upfront and store it in
// baseLength. This value will be set to zero if a write error occurs
// indicating that the data and length are no longer valid.
const uint32_t baseLength = sizeof(uint32_t) + 1;
uint32_t totalCustomLength = baseLength;
const char* knownFormats[] = {
kTextMime, kHTMLMime, kNativeHTMLMime, kRTFMime,
kURLMime, kURLDataMime, kURLDescriptionMime, kURLPrivateMime,
kPNGImageMime, kJPEGImageMime, kGIFImageMime, kNativeImageMime,
kFileMime, kFilePromiseMime, kFilePromiseURLMime,
kFilePromiseDestFilename, kFilePromiseDirectoryMime,
kMozTextInternal, kHTMLContext, kHTMLInfo };
/*
* Two passes are made here to iterate over all of the types. First, look for
* any types that are not in the list of known types. For this pass,
* handlingCustomFormats will be true. Data that corresponds to unknown types
* will be pulled out and inserted into a single type (kCustomTypesMime) by
* writing the data into a stream.
*
* The second pass will iterate over the formats looking for known types.
* These are added as is. The unknown types are all then inserted as a single
* type (kCustomTypesMime) in the same position of the first custom type. This
* model is used to maintain the format order as best as possible.
*
* The format of the kCustomTypesMime type is one or more of the following
* stored sequentially:
* <32-bit> type (only none or string is supported)
* <32-bit> length of format
* <wide string> format
* <32-bit> length of data
* <wide string> data
* A type of eCustomClipboardTypeId_None ends the list, without any following
* data.
*/
do {
for (uint32_t f = 0; f < count; f++) {
RefPtr<DataTransferItem> formatitem = item[f];
nsCOMPtr<nsIVariant> variant = formatitem->DataNoSecurityCheck();
if (!variant) { // skip empty items
continue;
}
nsAutoString type;
formatitem->GetInternalType(type);
// If the data is of one of the well-known formats, use it directly.
bool isCustomFormat = true;
for (uint32_t f = 0; f < ArrayLength(knownFormats); f++) {
if (type.EqualsASCII(knownFormats[f])) {
isCustomFormat = false;
break;
}
}
uint32_t lengthInBytes;
nsCOMPtr<nsISupports> convertedData;
if (handlingCustomFormats) {
if (!ConvertFromVariant(variant, getter_AddRefs(convertedData),
&lengthInBytes)) {
continue;
}
// When handling custom types, add the data to the stream if this is a
// custom type. If totalCustomLength is 0, then a write error occurred
// on a previous item, so ignore any others.
if (isCustomFormat && totalCustomLength > 0) {
// If it isn't a string, just ignore it. The dataTransfer is cached in
// the drag sesion during drag-and-drop, so non-strings will be
// available when dragging locally.
nsCOMPtr<nsISupportsString> str(do_QueryInterface(convertedData));
if (str) {
nsAutoString data;
str->GetData(data);
if (!stream) {
// Create a storage stream to write to.
NS_NewStorageStream(1024, UINT32_MAX, getter_AddRefs(storageStream));
nsCOMPtr<nsIOutputStream> outputStream;
storageStream->GetOutputStream(0, getter_AddRefs(outputStream));
stream = do_CreateInstance("@mozilla.org/binaryoutputstream;1");
stream->SetOutputStream(outputStream);
}
CheckedInt<uint32_t> formatLength =
CheckedInt<uint32_t>(type.Length()) * sizeof(nsString::char_type);
// The total size of the stream is the format length, the data
// length, two integers to hold the lengths and one integer for
// the string flag. Guard against large data by ignoring any that
// don't fit.
CheckedInt<uint32_t> newSize = formatLength + totalCustomLength +
lengthInBytes + (sizeof(uint32_t) * 3);
if (newSize.isValid()) {
// If a write error occurs, set totalCustomLength to 0 so that
// further processing gets ignored.
nsresult rv = stream->Write32(eCustomClipboardTypeId_String);
if (NS_WARN_IF(NS_FAILED(rv))) {
totalCustomLength = 0;
continue;
}
rv = stream->Write32(formatLength.value());
if (NS_WARN_IF(NS_FAILED(rv))) {
totalCustomLength = 0;
continue;
}
rv = stream->WriteBytes((const char *)type.get(), formatLength.value());
if (NS_WARN_IF(NS_FAILED(rv))) {
totalCustomLength = 0;
continue;
}
rv = stream->Write32(lengthInBytes);
if (NS_WARN_IF(NS_FAILED(rv))) {
totalCustomLength = 0;
continue;
}
rv = stream->WriteBytes((const char *)data.get(), lengthInBytes);
if (NS_WARN_IF(NS_FAILED(rv))) {
totalCustomLength = 0;
continue;
}
totalCustomLength = newSize.value();
}
}
}
} else if (isCustomFormat && stream) {
// This is the second pass of the loop (handlingCustomFormats is false).
// When encountering the first custom format, append all of the stream
// at this position. If totalCustomLength is 0 indicating a write error
// occurred, or no data has been added to it, don't output anything,
if (totalCustomLength > baseLength) {
// Write out an end of data terminator.
nsresult rv = stream->Write32(eCustomClipboardTypeId_None);
if (NS_SUCCEEDED(rv)) {
nsCOMPtr<nsIInputStream> inputStream;
storageStream->NewInputStream(0, getter_AddRefs(inputStream));
RefPtr<nsStringBuffer> stringBuffer =
nsStringBuffer::Alloc(totalCustomLength);
// Subtract off the null terminator when reading.
totalCustomLength--;
// Read the data from the stream and add a null-terminator as
// ToString needs it.
uint32_t amountRead;
rv = inputStream->Read(static_cast<char*>(stringBuffer->Data()),
totalCustomLength, &amountRead);
if (NS_SUCCEEDED(rv)) {
static_cast<char*>(stringBuffer->Data())[amountRead] = 0;
nsCString str;
stringBuffer->ToString(totalCustomLength, str);
nsCOMPtr<nsISupportsCString>
strSupports(do_CreateInstance(NS_SUPPORTS_CSTRING_CONTRACTID));
strSupports->SetData(str);
nsresult rv = transferable->SetTransferData(kCustomTypesMime,
strSupports,
totalCustomLength);
if (NS_FAILED(rv)) {
return nullptr;
}
added = true;
}
}
}
// Clear the stream so it doesn't get used again.
stream = nullptr;
} else {
// This is the second pass of the loop and a known type is encountered.
// Add it as is.
if (!ConvertFromVariant(variant, getter_AddRefs(convertedData),
&lengthInBytes)) {
continue;
}
// The underlying drag code uses text/unicode, so use that instead of
// text/plain
const char* format;
NS_ConvertUTF16toUTF8 utf8format(type);
if (utf8format.EqualsLiteral(kTextMime)) {
format = kUnicodeMime;
} else {
format = utf8format.get();
}
// If a converter is set for a format, set the converter for the
// transferable and don't add the item
nsCOMPtr<nsIFormatConverter> converter =
do_QueryInterface(convertedData);
if (converter) {
transferable->AddDataFlavor(format);
transferable->SetConverter(converter);
continue;
}
nsresult rv = transferable->SetTransferData(format, convertedData,
lengthInBytes);
if (NS_FAILED(rv)) {
return nullptr;
}
added = true;
}
}
handlingCustomFormats = !handlingCustomFormats;
} while (!handlingCustomFormats);
// only return the transferable if data was successfully added to it
if (added) {
return transferable.forget();
}
return nullptr;
}