gecko/dom/workers/FileReaderSyncPrivate.cpp

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
2012-05-21 04:12:37 -07:00
/* 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 "FileReaderSyncPrivate.h"
#include "nsCExternalHandlerService.h"
#include "nsComponentManagerUtils.h"
#include "nsCOMPtr.h"
#include "nsDOMClassInfoID.h"
#include "nsDOMError.h"
#include "nsIDOMFile.h"
#include "nsCharsetAlias.h"
#include "nsICharsetDetector.h"
#include "nsIConverterInputStream.h"
#include "nsIInputStream.h"
#include "nsIPlatformCharset.h"
#include "nsISeekableStream.h"
#include "nsISupportsImpl.h"
#include "nsISupportsImpl.h"
#include "nsNetUtil.h"
#include "nsServiceManagerUtils.h"
#include "RuntimeService.h"
#include "mozilla/Base64.h"
USING_WORKERS_NAMESPACE
NS_IMPL_ISUPPORTS1(FileReaderSyncPrivate, nsICharsetDetectionObserver)
FileReaderSyncPrivate::FileReaderSyncPrivate()
{
MOZ_COUNT_CTOR(mozilla::dom::workers::FileReaderSyncPrivate);
}
FileReaderSyncPrivate::~FileReaderSyncPrivate()
{
MOZ_COUNT_DTOR(mozilla::dom::workers::FileReaderSyncPrivate);
}
nsresult
FileReaderSyncPrivate::ReadAsArrayBuffer(nsIDOMBlob* aBlob, PRUint32 aLength,
uint8* aBuffer)
{
nsCOMPtr<nsIInputStream> stream;
nsresult rv = aBlob->GetInternalStream(getter_AddRefs(stream));
NS_ENSURE_SUCCESS(rv, rv);
PRUint32 numRead;
rv = stream->Read((char*)aBuffer, aLength, &numRead);
NS_ENSURE_SUCCESS(rv, rv);
NS_ASSERTION(numRead == aLength, "failed to read data");
return NS_OK;
}
nsresult
FileReaderSyncPrivate::ReadAsBinaryString(nsIDOMBlob* aBlob, nsAString& aResult)
{
nsCOMPtr<nsIInputStream> stream;
nsresult rv = aBlob->GetInternalStream(getter_AddRefs(stream));
NS_ENSURE_SUCCESS(rv, rv);
PRUint32 numRead;
do {
char readBuf[4096];
rv = stream->Read(readBuf, sizeof(readBuf), &numRead);
NS_ENSURE_SUCCESS(rv, rv);
PRUint32 oldLength = aResult.Length();
AppendASCIItoUTF16(Substring(readBuf, readBuf + numRead), aResult);
if (aResult.Length() - oldLength != numRead) {
return NS_ERROR_OUT_OF_MEMORY;
}
} while (numRead > 0);
return NS_OK;
}
nsresult
FileReaderSyncPrivate::ReadAsText(nsIDOMBlob* aBlob,
const nsAString& aEncoding, nsAString& aResult)
{
nsCOMPtr<nsIInputStream> stream;
nsresult rv = aBlob->GetInternalStream(getter_AddRefs(stream));
NS_ENSURE_SUCCESS(rv, rv);
nsCString charsetGuess;
if (aEncoding.IsEmpty()) {
rv = GuessCharset(stream, charsetGuess);
NS_ENSURE_SUCCESS(rv, rv);
nsCOMPtr<nsISeekableStream> seekable = do_QueryInterface(stream);
NS_ENSURE_TRUE(seekable, NS_ERROR_FAILURE);
// Seek to 0 because guessing the charset advances the stream.
rv = seekable->Seek(nsISeekableStream::NS_SEEK_SET, 0);
NS_ENSURE_SUCCESS(rv, rv);
} else {
CopyUTF16toUTF8(aEncoding, charsetGuess);
}
nsCString charset;
rv = nsCharsetAlias::GetPreferred(charsetGuess, charset);
NS_ENSURE_SUCCESS(rv, rv);
return ConvertStream(stream, charset.get(), aResult);
}
nsresult
FileReaderSyncPrivate::ReadAsDataURL(nsIDOMBlob* aBlob, nsAString& aResult)
{
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;
nsresult rv = aBlob->GetInternalStream(getter_AddRefs(stream));
NS_ENSURE_SUCCESS(rv, rv);
PRUint64 size;
rv = aBlob->GetSize(&size);
NS_ENSURE_SUCCESS(rv, rv);
nsCOMPtr<nsIInputStream> bufferedStream;
rv = NS_NewBufferedInputStream(getter_AddRefs(bufferedStream), stream, size);
NS_ENSURE_SUCCESS(rv, rv);
nsAutoString encodedData;
rv = Base64EncodeInputStream(bufferedStream, encodedData, size);
NS_ENSURE_SUCCESS(rv, rv);
scratchResult.Append(encodedData);
aResult = scratchResult;
return NS_OK;
}
nsresult
FileReaderSyncPrivate::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);
PRUint32 numChars;
nsString result;
while (NS_SUCCEEDED(unicharStream->ReadString(8192, result, &numChars)) &&
numChars > 0) {
PRUint32 oldLength = aResult.Length();
aResult.Append(result);
if (aResult.Length() - oldLength != result.Length()) {
return NS_ERROR_OUT_OF_MEMORY;
}
}
return rv;
}
nsresult
FileReaderSyncPrivate::GuessCharset(nsIInputStream *aStream,
nsACString &aCharset)
{
// First try the universal charset detector
nsCOMPtr<nsICharsetDetector> detector
= do_CreateInstance(NS_CHARSET_DETECTOR_CONTRACTID_BASE
"universal_charset_detector");
if (!detector) {
RuntimeService* runtime = RuntimeService::GetService();
NS_ASSERTION(runtime, "This should never be null!");
// No universal charset detector, try the default charset detector
const nsACString& detectorName = runtime->GetDetectorName();
if (!detectorName.IsEmpty()) {
nsCAutoString detectorContractID;
detectorContractID.AssignLiteral(NS_CHARSET_DETECTOR_CONTRACTID_BASE);
detectorContractID += detectorName;
detector = do_CreateInstance(detectorContractID.get());
}
}
nsresult rv;
if (detector) {
detector->Init(this);
bool done;
PRUint32 numRead;
do {
char readBuf[4096];
rv = aStream->Read(readBuf, sizeof(readBuf), &numRead);
NS_ENSURE_SUCCESS(rv, rv);
if (numRead <= 0) {
break;
}
rv = detector->DoIt(readBuf, numRead, &done);
NS_ENSURE_SUCCESS(rv, rv);
} while (!done);
rv = detector->Done();
NS_ENSURE_SUCCESS(rv, rv);
} else {
// no charset detector available, check the BOM
unsigned char sniffBuf[4];
PRUint32 numRead;
rv = aStream->Read(reinterpret_cast<char*>(sniffBuf),
sizeof(sniffBuf), &numRead);
NS_ENSURE_SUCCESS(rv, rv);
if (numRead >= 4 &&
sniffBuf[0] == 0x00 &&
sniffBuf[1] == 0x00 &&
sniffBuf[2] == 0xfe &&
sniffBuf[3] == 0xff) {
mCharset = "UTF-32BE";
} else if (numRead >= 4 &&
sniffBuf[0] == 0xff &&
sniffBuf[1] == 0xfe &&
sniffBuf[2] == 0x00 &&
sniffBuf[3] == 0x00) {
mCharset = "UTF-32LE";
} else if (numRead >= 2 &&
sniffBuf[0] == 0xfe &&
sniffBuf[1] == 0xff) {
mCharset = "UTF-16BE";
} else if (numRead >= 2 &&
sniffBuf[0] == 0xff &&
sniffBuf[1] == 0xfe) {
mCharset = "UTF-16LE";
} else if (numRead >= 3 &&
sniffBuf[0] == 0xef &&
sniffBuf[1] == 0xbb &&
sniffBuf[2] == 0xbf) {
mCharset = "UTF-8";
}
}
if (mCharset.IsEmpty()) {
RuntimeService* runtime = RuntimeService::GetService();
mCharset = runtime->GetSystemCharset();
}
if (mCharset.IsEmpty()) {
// no sniffed or default charset, try UTF-8
mCharset.AssignLiteral("UTF-8");
}
aCharset = mCharset;
mCharset.Truncate();
return NS_OK;
}
NS_IMETHODIMP
FileReaderSyncPrivate::Notify(const char* aCharset, nsDetectionConfident aConf)
{
mCharset.Assign(aCharset);
return NS_OK;
}