gecko-dev/dom/workers/FileReaderSync.cpp

265 строки
7.5 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 "FileReaderSync.h"
#include "jsfriendapi.h"
#include "mozilla/unused.h"
#include "mozilla/Base64.h"
#include "mozilla/dom/EncodingUtils.h"
#include "mozilla/dom/File.h"
#include "nsContentUtils.h"
#include "mozilla/dom/FileReaderSyncBinding.h"
#include "nsCExternalHandlerService.h"
#include "nsComponentManagerUtils.h"
#include "nsCOMPtr.h"
#include "nsDOMClassInfoID.h"
#include "nsError.h"
#include "nsIConverterInputStream.h"
#include "nsIInputStream.h"
#include "nsISeekableStream.h"
#include "nsISupportsImpl.h"
#include "nsNetUtil.h"
#include "nsServiceManagerUtils.h"
#include "RuntimeService.h"
using namespace mozilla;
using namespace mozilla::dom;
using mozilla::dom::Optional;
using mozilla::dom::GlobalObject;
// static
already_AddRefed<FileReaderSync>
FileReaderSync::Constructor(const GlobalObject& aGlobal, ErrorResult& aRv)
{
RefPtr<FileReaderSync> frs = new FileReaderSync();
return frs.forget();
}
bool
FileReaderSync::WrapObject(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto,
JS::MutableHandle<JSObject*> aReflector)
{
return FileReaderSyncBinding::Wrap(aCx, this, aGivenProto, aReflector);
}
void
FileReaderSync::ReadAsArrayBuffer(JSContext* aCx,
JS::Handle<JSObject*> aScopeObj,
Blob& aBlob,
JS::MutableHandle<JSObject*> aRetval,
ErrorResult& aRv)
{
uint64_t blobSize = aBlob.GetSize(aRv);
if (NS_WARN_IF(aRv.Failed())) {
return;
}
UniquePtr<char[], JS::FreePolicy> bufferData(js_pod_malloc<char>(blobSize));
if (!bufferData) {
aRv.Throw(NS_ERROR_OUT_OF_MEMORY);
return;
}
nsCOMPtr<nsIInputStream> stream;
aBlob.GetInternalStream(getter_AddRefs(stream), aRv);
if (NS_WARN_IF(aRv.Failed())) {
return;
}
uint32_t numRead;
aRv = stream->Read(bufferData.get(), blobSize, &numRead);
if (NS_WARN_IF(aRv.Failed())) {
return;
}
NS_ASSERTION(numRead == blobSize, "failed to read data");
JSObject* arrayBuffer = JS_NewArrayBufferWithContents(aCx, blobSize, bufferData.get());
if (!arrayBuffer) {
aRv.Throw(NS_ERROR_OUT_OF_MEMORY);
return;
}
// arrayBuffer takes the ownership when it is not null. Otherwise we
// need to release it explicitly.
mozilla::Unused << bufferData.release();
aRetval.set(arrayBuffer);
}
void
FileReaderSync::ReadAsBinaryString(Blob& aBlob,
nsAString& aResult,
ErrorResult& aRv)
{
nsCOMPtr<nsIInputStream> stream;
aBlob.GetInternalStream(getter_AddRefs(stream), aRv);
if (NS_WARN_IF(aRv.Failed())) {
return;
}
uint32_t numRead;
do {
char readBuf[4096];
aRv = stream->Read(readBuf, sizeof(readBuf), &numRead);
if (NS_WARN_IF(aRv.Failed())) {
return;
}
uint32_t oldLength = aResult.Length();
AppendASCIItoUTF16(Substring(readBuf, readBuf + numRead), aResult);
if (aResult.Length() - oldLength != numRead) {
aRv.Throw(NS_ERROR_OUT_OF_MEMORY);
return;
}
} while (numRead > 0);
}
void
FileReaderSync::ReadAsText(Blob& aBlob,
const Optional<nsAString>& aEncoding,
nsAString& aResult,
ErrorResult& aRv)
{
nsCOMPtr<nsIInputStream> stream;
aBlob.GetInternalStream(getter_AddRefs(stream), aRv);
if (NS_WARN_IF(aRv.Failed())) {
return;
}
nsAutoCString encoding;
unsigned char sniffBuf[3] = { 0, 0, 0 };
uint32_t numRead;
aRv = stream->Read(reinterpret_cast<char*>(sniffBuf),
sizeof(sniffBuf), &numRead);
if (NS_WARN_IF(aRv.Failed())) {
return;
}
// The BOM sniffing is baked into the "decode" part of the Encoding
// Standard, which the File API references.
if (!nsContentUtils::CheckForBOM(sniffBuf, numRead, encoding)) {
// BOM sniffing failed. Try the API argument.
if (!aEncoding.WasPassed() ||
!EncodingUtils::FindEncodingForLabel(aEncoding.Value(),
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");
}
}
}
nsCOMPtr<nsISeekableStream> seekable = do_QueryInterface(stream);
if (!seekable) {
aRv.Throw(NS_ERROR_FAILURE);
return;
}
// Seek to 0 because to undo the BOM sniffing advance. UTF-8 and UTF-16
// decoders will swallow the BOM.
aRv = seekable->Seek(nsISeekableStream::NS_SEEK_SET, 0);
if (NS_WARN_IF(aRv.Failed())) {
return;
}
aRv = ConvertStream(stream, encoding.get(), aResult);
if (NS_WARN_IF(aRv.Failed())) {
return;
}
}
void
FileReaderSync::ReadAsDataURL(Blob& aBlob, nsAString& aResult,
ErrorResult& aRv)
{
nsAutoString scratchResult;
scratchResult.AssignLiteral("data:");
nsString contentType;
aBlob.GetType(contentType);
if (contentType.IsEmpty()) {
scratchResult.AppendLiteral("application/octet-stream");
} else {
scratchResult.Append(contentType);
}
scratchResult.AppendLiteral(";base64,");
nsCOMPtr<nsIInputStream> stream;
aBlob.GetInternalStream(getter_AddRefs(stream), aRv);
if (NS_WARN_IF(aRv.Failed())){
return;
}
uint64_t size = aBlob.GetSize(aRv);
if (NS_WARN_IF(aRv.Failed())){
return;
}
nsCOMPtr<nsIInputStream> bufferedStream;
aRv = NS_NewBufferedInputStream(getter_AddRefs(bufferedStream), stream, size);
if (NS_WARN_IF(aRv.Failed())){
return;
}
nsAutoString encodedData;
aRv = Base64EncodeInputStream(bufferedStream, encodedData, size);
if (NS_WARN_IF(aRv.Failed())){
return;
}
scratchResult.Append(encodedData);
aResult = scratchResult;
}
nsresult
FileReaderSync::ConvertStream(nsIInputStream *aStream,
const char *aCharset,
nsAString &aResult)
{
nsCOMPtr<nsIConverterInputStream> converterStream =
do_CreateInstance("@mozilla.org/intl/converter-input-stream;1");
NS_ENSURE_TRUE(converterStream, NS_ERROR_FAILURE);
nsresult rv = converterStream->Init(aStream, aCharset, 8192,
nsIConverterInputStream::DEFAULT_REPLACEMENT_CHARACTER);
NS_ENSURE_SUCCESS(rv, rv);
nsCOMPtr<nsIUnicharInputStream> unicharStream =
do_QueryInterface(converterStream);
NS_ENSURE_TRUE(unicharStream, NS_ERROR_FAILURE);
uint32_t numChars;
nsString result;
while (NS_SUCCEEDED(unicharStream->ReadString(8192, result, &numChars)) &&
numChars > 0) {
uint32_t oldLength = aResult.Length();
aResult.Append(result);
if (aResult.Length() - oldLength != result.Length()) {
return NS_ERROR_OUT_OF_MEMORY;
}
}
return rv;
}