gecko-dev/dom/base/nsDOMFileReader.cpp

536 lines
14 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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/. */
#include "nsDOMFileReader.h"
#include "nsContentCID.h"
#include "nsContentUtils.h"
#include "nsDOMClassInfoID.h"
#include "nsError.h"
#include "nsIFile.h"
#include "nsNetCID.h"
#include "nsXPCOM.h"
#include "nsIDOMEventListener.h"
#include "nsJSEnvironment.h"
#include "nsCycleCollectionParticipant.h"
#include "mozilla/Base64.h"
#include "mozilla/dom/EncodingUtils.h"
#include "mozilla/dom/File.h"
#include "mozilla/dom/FileReaderBinding.h"
#include "xpcpublic.h"
#include "nsDOMJSUtils.h"
#include "jsfriendapi.h"
#include "nsITransport.h"
#include "nsIStreamTransportService.h"
using namespace mozilla;
using namespace mozilla::dom;
#define LOAD_STR "load"
#define LOADSTART_STR "loadstart"
#define LOADEND_STR "loadend"
static NS_DEFINE_CID(kStreamTransportServiceCID, NS_STREAMTRANSPORTSERVICE_CID);
NS_IMPL_CYCLE_COLLECTION_CLASS(nsDOMFileReader)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(nsDOMFileReader,
FileIOObject)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mBlob)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(nsDOMFileReader,
FileIOObject)
tmp->mResultArrayBuffer = nullptr;
NS_IMPL_CYCLE_COLLECTION_UNLINK(mBlob)
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN_INHERITED(nsDOMFileReader,
DOMEventTargetHelper)
NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mResultArrayBuffer)
NS_IMPL_CYCLE_COLLECTION_TRACE_END
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION_INHERITED(nsDOMFileReader)
NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
NS_INTERFACE_MAP_ENTRY(nsIDOMFileReader)
NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
NS_INTERFACE_MAP_END_INHERITING(FileIOObject)
NS_IMPL_ADDREF_INHERITED(nsDOMFileReader, FileIOObject)
NS_IMPL_RELEASE_INHERITED(nsDOMFileReader, FileIOObject)
NS_IMPL_EVENT_HANDLER(nsDOMFileReader, load)
NS_IMPL_EVENT_HANDLER(nsDOMFileReader, loadend)
NS_IMPL_EVENT_HANDLER(nsDOMFileReader, loadstart)
NS_IMPL_FORWARD_EVENT_HANDLER(nsDOMFileReader, abort, FileIOObject)
NS_IMPL_FORWARD_EVENT_HANDLER(nsDOMFileReader, progress, FileIOObject)
NS_IMPL_FORWARD_EVENT_HANDLER(nsDOMFileReader, error, FileIOObject)
void
nsDOMFileReader::RootResultArrayBuffer()
{
mozilla::HoldJSObjects(this);
}
//nsDOMFileReader constructors/initializers
nsDOMFileReader::nsDOMFileReader()
: mFileData(nullptr),
mDataLen(0), mDataFormat(FILE_AS_BINARY),
mResultArrayBuffer(nullptr)
{
SetDOMStringToNull(mResult);
}
nsDOMFileReader::~nsDOMFileReader()
{
FreeFileData();
mResultArrayBuffer = nullptr;
mozilla::DropJSObjects(this);
}
/**
* This Init method is called from the factory constructor.
*/
nsresult
nsDOMFileReader::Init()
{
// Instead of grabbing some random global from the context stack,
// let's use the default one (junk scope) for now.
// We should move away from this Init...
BindToOwner(xpc::NativeGlobal(xpc::PrivilegedJunkScope()));
return NS_OK;
}
/* static */ already_AddRefed<nsDOMFileReader>
nsDOMFileReader::Constructor(const GlobalObject& aGlobal, ErrorResult& aRv)
{
nsRefPtr<nsDOMFileReader> fileReader = new nsDOMFileReader();
nsCOMPtr<nsPIDOMWindow> owner = do_QueryInterface(aGlobal.GetAsSupports());
if (!owner) {
NS_WARNING("Unexpected owner");
aRv.Throw(NS_ERROR_FAILURE);
return nullptr;
}
fileReader->BindToOwner(owner);
return fileReader.forget();
}
// nsIInterfaceRequestor
NS_IMETHODIMP
nsDOMFileReader::GetInterface(const nsIID & aIID, void **aResult)
{
return QueryInterface(aIID, aResult);
}
// nsIDOMFileReader
NS_IMETHODIMP
nsDOMFileReader::GetReadyState(uint16_t *aReadyState)
{
*aReadyState = ReadyState();
return NS_OK;
}
void
nsDOMFileReader::GetResult(JSContext* aCx, JS::MutableHandle<JS::Value> aResult,
ErrorResult& aRv)
{
aRv = GetResult(aCx, aResult);
}
NS_IMETHODIMP
nsDOMFileReader::GetResult(JSContext* aCx, JS::MutableHandle<JS::Value> aResult)
{
JS::Rooted<JS::Value> result(aCx);
if (mDataFormat == FILE_AS_ARRAYBUFFER) {
if (mReadyState == nsIDOMFileReader::DONE && mResultArrayBuffer) {
result.setObject(*mResultArrayBuffer);
} else {
result.setNull();
}
if (!JS_WrapValue(aCx, &result)) {
return NS_ERROR_FAILURE;
}
aResult.set(result);
return NS_OK;
}
nsString tmpResult = mResult;
if (!xpc::StringToJsval(aCx, tmpResult, aResult)) {
return NS_ERROR_FAILURE;
}
return NS_OK;
}
NS_IMETHODIMP
nsDOMFileReader::GetError(nsISupports** aError)
{
NS_IF_ADDREF(*aError = GetError());
return NS_OK;
}
NS_IMETHODIMP
nsDOMFileReader::ReadAsArrayBuffer(nsIDOMBlob* aBlob, JSContext* aCx)
{
NS_ENSURE_TRUE(aBlob, NS_ERROR_NULL_POINTER);
ErrorResult rv;
nsRefPtr<Blob> blob = static_cast<Blob*>(aBlob);
ReadAsArrayBuffer(aCx, *blob, rv);
return rv.StealNSResult();
}
NS_IMETHODIMP
nsDOMFileReader::ReadAsBinaryString(nsIDOMBlob* aBlob)
{
NS_ENSURE_TRUE(aBlob, NS_ERROR_NULL_POINTER);
ErrorResult rv;
nsRefPtr<Blob> blob = static_cast<Blob*>(aBlob);
ReadAsBinaryString(*blob, rv);
return rv.StealNSResult();
}
NS_IMETHODIMP
nsDOMFileReader::ReadAsText(nsIDOMBlob* aBlob,
const nsAString &aCharset)
{
NS_ENSURE_TRUE(aBlob, NS_ERROR_NULL_POINTER);
ErrorResult rv;
nsRefPtr<Blob> blob = static_cast<Blob*>(aBlob);
ReadAsText(*blob, aCharset, rv);
return rv.StealNSResult();
}
NS_IMETHODIMP
nsDOMFileReader::ReadAsDataURL(nsIDOMBlob* aBlob)
{
NS_ENSURE_TRUE(aBlob, NS_ERROR_NULL_POINTER);
ErrorResult rv;
nsRefPtr<Blob> blob = static_cast<Blob*>(aBlob);
ReadAsDataURL(*blob, rv);
return rv.StealNSResult();
}
NS_IMETHODIMP
nsDOMFileReader::Abort()
{
ErrorResult rv;
FileIOObject::Abort(rv);
return rv.StealNSResult();
}
/* virtual */ void
nsDOMFileReader::DoAbort(nsAString& aEvent)
{
// Revert status and result attributes
SetDOMStringToNull(mResult);
mResultArrayBuffer = nullptr;
mAsyncStream = nullptr;
mBlob = nullptr;
//Clean up memory buffer
FreeFileData();
// Tell the base class which event to dispatch
aEvent = NS_LITERAL_STRING(LOADEND_STR);
}
static
NS_METHOD
ReadFuncBinaryString(nsIInputStream* in,
void* closure,
const char* fromRawSegment,
uint32_t toOffset,
uint32_t count,
uint32_t *writeCount)
{
char16_t* dest = static_cast<char16_t*>(closure) + toOffset;
char16_t* end = dest + count;
const unsigned char* source = (const unsigned char*)fromRawSegment;
while (dest != end) {
*dest = *source;
++dest;
++source;
}
*writeCount = count;
return NS_OK;
}
nsresult
nsDOMFileReader::DoOnLoadEnd(nsresult aStatus,
nsAString& aSuccessEvent,
nsAString& aTerminationEvent)
{
// Make sure we drop all the objects that could hold files open now.
nsCOMPtr<nsIAsyncInputStream> stream;
mAsyncStream.swap(stream);
nsRefPtr<Blob> blob;
mBlob.swap(blob);
aSuccessEvent = NS_LITERAL_STRING(LOAD_STR);
aTerminationEvent = NS_LITERAL_STRING(LOADEND_STR);
// Clear out the data if necessary
if (NS_FAILED(aStatus)) {
FreeFileData();
return NS_OK;
}
nsresult rv = NS_OK;
switch (mDataFormat) {
case FILE_AS_ARRAYBUFFER: {
AutoJSAPI jsapi;
if (NS_WARN_IF(!jsapi.Init(mozilla::DOMEventTargetHelper::GetParentObject()))) {
return NS_ERROR_FAILURE;
}
RootResultArrayBuffer();
mResultArrayBuffer = JS_NewArrayBufferWithContents(jsapi.cx(), mTotal, mFileData);
if (!mResultArrayBuffer) {
JS_ClearPendingException(jsapi.cx());
rv = NS_ERROR_OUT_OF_MEMORY;
} else {
mFileData = nullptr; // Transfer ownership
}
break;
}
case FILE_AS_BINARY:
break; //Already accumulated mResult
case FILE_AS_TEXT:
if (!mFileData) {
if (mDataLen) {
rv = NS_ERROR_OUT_OF_MEMORY;
break;
}
rv = GetAsText(blob, mCharset, "", mDataLen, mResult);
break;
}
rv = GetAsText(blob, mCharset, mFileData, mDataLen, mResult);
break;
case FILE_AS_DATAURL:
rv = GetAsDataURL(blob, mFileData, mDataLen, mResult);
break;
}
mResult.SetIsVoid(false);
FreeFileData();
return rv;
}
nsresult
nsDOMFileReader::DoReadData(nsIAsyncInputStream* aStream, uint64_t aCount)
{
MOZ_ASSERT(aStream);
if (mDataFormat == FILE_AS_BINARY) {
//Continuously update our binary string as data comes in
uint32_t oldLen = mResult.Length();
NS_ASSERTION(mResult.Length() == mDataLen,
"unexpected mResult length");
if (uint64_t(oldLen) + aCount > UINT32_MAX)
return NS_ERROR_OUT_OF_MEMORY;
char16_t *buf = nullptr;
mResult.GetMutableData(&buf, oldLen + aCount, fallible);
NS_ENSURE_TRUE(buf, NS_ERROR_OUT_OF_MEMORY);
uint32_t bytesRead = 0;
aStream->ReadSegments(ReadFuncBinaryString, buf + oldLen, aCount,
&bytesRead);
NS_ASSERTION(bytesRead == aCount, "failed to read data");
}
else {
//Update memory buffer to reflect the contents of the file
if (mDataLen + aCount > UINT32_MAX) {
// PR_Realloc doesn't support over 4GB memory size even if 64-bit OS
return NS_ERROR_OUT_OF_MEMORY;
}
if (mDataFormat != FILE_AS_ARRAYBUFFER) {
mFileData = (char *) realloc(mFileData, mDataLen + aCount);
NS_ENSURE_TRUE(mFileData, NS_ERROR_OUT_OF_MEMORY);
}
uint32_t bytesRead = 0;
aStream->Read(mFileData + mDataLen, aCount, &bytesRead);
NS_ASSERTION(bytesRead == aCount, "failed to read data");
}
mDataLen += aCount;
return NS_OK;
}
// Helper methods
void
nsDOMFileReader::ReadFileContent(Blob& aBlob,
const nsAString &aCharset,
eDataFormat aDataFormat,
ErrorResult& aRv)
{
//Implicit abort to clear any other activity going on
Abort();
mError = nullptr;
SetDOMStringToNull(mResult);
mTransferred = 0;
mTotal = 0;
mReadyState = nsIDOMFileReader::EMPTY;
FreeFileData();
mBlob = &aBlob;
mDataFormat = aDataFormat;
CopyUTF16toUTF8(aCharset, mCharset);
nsresult rv;
nsCOMPtr<nsIStreamTransportService> sts =
do_GetService(kStreamTransportServiceCID, &rv);
if (NS_WARN_IF(NS_FAILED(rv))) {
aRv.Throw(rv);
return;
}
nsCOMPtr<nsIInputStream> stream;
mBlob->GetInternalStream(getter_AddRefs(stream), aRv);
if (NS_WARN_IF(aRv.Failed())) {
return;
}
nsCOMPtr<nsITransport> transport;
rv = sts->CreateInputTransport(stream,
/* aStartOffset */ 0,
/* aReadLimit */ -1,
/* aCloseWhenDone */ true,
getter_AddRefs(transport));
if (NS_WARN_IF(NS_FAILED(rv))) {
aRv.Throw(rv);
return;
}
nsCOMPtr<nsIInputStream> wrapper;
rv = transport->OpenInputStream(/* aFlags */ 0,
/* aSegmentSize */ 0,
/* aSegmentCount */ 0,
getter_AddRefs(wrapper));
if (NS_WARN_IF(NS_FAILED(rv))) {
aRv.Throw(rv);
return;
}
MOZ_ASSERT(!mAsyncStream);
mAsyncStream = do_QueryInterface(wrapper);
MOZ_ASSERT(mAsyncStream);
mTotal = mBlob->GetSize(aRv);
if (NS_WARN_IF(aRv.Failed())) {
return;
}
rv = DoAsyncWait(mAsyncStream);
if (NS_WARN_IF(NS_FAILED(rv))) {
aRv.Throw(rv);
return;
}
//FileReader should be in loading state here
mReadyState = nsIDOMFileReader::LOADING;
DispatchProgressEvent(NS_LITERAL_STRING(LOADSTART_STR));
if (mDataFormat == FILE_AS_ARRAYBUFFER) {
mFileData = js_pod_malloc<char>(mTotal);
if (!mFileData) {
NS_WARNING("Preallocation failed for ReadFileData");
aRv.Throw(NS_ERROR_OUT_OF_MEMORY);
}
}
}
nsresult
nsDOMFileReader::GetAsText(Blob *aBlob,
const nsACString &aCharset,
const char *aFileData,
uint32_t aDataLen,
nsAString& aResult)
{
// The BOM sniffing is baked into the "decode" part of the Encoding
// Standard, which the File API references.
nsAutoCString encoding;
if (!nsContentUtils::CheckForBOM(
reinterpret_cast<const unsigned char *>(aFileData),
aDataLen,
encoding)) {
// BOM sniffing failed. Try the API argument.
if (!EncodingUtils::FindEncodingForLabel(aCharset,
encoding)) {
// API argument failed. Try the type property of the blob.
nsAutoString type16;
aBlob->GetType(type16);
NS_ConvertUTF16toUTF8 type(type16);
nsAutoCString specifiedCharset;
bool haveCharset;
int32_t charsetStart, charsetEnd;
NS_ExtractCharsetFromContentType(type,
specifiedCharset,
&haveCharset,
&charsetStart,
&charsetEnd);
if (!EncodingUtils::FindEncodingForLabel(specifiedCharset, encoding)) {
// Type property failed. Use UTF-8.
encoding.AssignLiteral("UTF-8");
}
}
}
nsDependentCSubstring data(aFileData, aDataLen);
return nsContentUtils::ConvertStringFromEncoding(encoding, data, aResult);
}
nsresult
nsDOMFileReader::GetAsDataURL(Blob *aBlob,
const char *aFileData,
uint32_t aDataLen,
nsAString& aResult)
{
aResult.AssignLiteral("data:");
nsString contentType;
aBlob->GetType(contentType);
if (!contentType.IsEmpty()) {
aResult.Append(contentType);
} else {
aResult.AppendLiteral("application/octet-stream");
}
aResult.AppendLiteral(";base64,");
nsCString encodedData;
nsresult rv = Base64Encode(Substring(aFileData, aDataLen), encodedData);
NS_ENSURE_SUCCESS(rv, rv);
if (!AppendASCIItoUTF16(encodedData, aResult, fallible)) {
return NS_ERROR_OUT_OF_MEMORY;
}
return NS_OK;
}
/* virtual */ JSObject*
nsDOMFileReader::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto)
{
return FileReaderBinding::Wrap(aCx, this, aGivenProto);
}