The Tor Browser: content/base/src/nsDOMFileReader.cpp@6474c204b198 (annotated)

content/base/src/nsDOMFileReader.cpp@6474c204b198 (annotated)

content/base/src/nsDOMFileReader.cpp

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* 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 "nsDOMFile.h"
 #include "nsError.h"
 #include "nsIConverterInputStream.h"
 #include "nsIDocument.h"
 #include "nsIFile.h"
 #include "nsIFileStreams.h"
 #include "nsIInputStream.h"
 #include "nsIMIMEService.h"
 #include "nsIUnicodeDecoder.h"
 #include "nsNetCID.h"
 #include "nsNetUtil.h"
 #include "nsLayoutCID.h"
 #include "nsXPIDLString.h"
 #include "nsReadableUtils.h"
 #include "nsIURI.h"
 #include "nsStreamUtils.h"
 #include "nsXPCOM.h"
 #include "nsIDOMEventListener.h"
 #include "nsJSEnvironment.h"
 #include "nsIScriptGlobalObject.h"
 #include "nsCExternalHandlerService.h"
 #include "nsIStreamConverterService.h"
 #include "nsCycleCollectionParticipant.h"
 #include "nsIScriptObjectPrincipal.h"
 #include "nsHostObjectProtocolHandler.h"
 #include "mozilla/Base64.h"
 #include "mozilla/DOMEventTargetHelper.h"
 #include "mozilla/Preferences.h"
 #include "mozilla/dom/EncodingUtils.h"
 #include "mozilla/dom/FileReaderBinding.h"
 #include "xpcpublic.h"
 #include "nsIScriptSecurityManager.h"
 #include "nsDOMJSUtils.h"
 #include "jsfriendapi.h"
 using namespace mozilla;
 using namespace mozilla::dom;
 #define LOAD_STR "load"
 #define LOADSTART_STR "loadstart"
 #define LOADEND_STR "loadend"
 NS_IMPL_CYCLE_COLLECTION_CLASS(nsDOMFileReader)
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(nsDOMFileReader,
                                                   FileIOObject)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mFile)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPrincipal)
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
 NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(nsDOMFileReader,
                                                 FileIOObject)
   tmp->mResultArrayBuffer = nullptr;
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mFile)
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mPrincipal)
 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(nsIInterfaceRequestor)
   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);
   SetIsDOMBinding();
 }
 nsDOMFileReader::~nsDOMFileReader()
 {
   FreeFileData();
   mResultArrayBuffer = nullptr;
   mozilla::DropJSObjects(this);
 }
 /**
  * This Init method is called from the factory constructor.
  */
 nsresult
 nsDOMFileReader::Init()
 {
   nsIScriptSecurityManager* secMan = nsContentUtils::GetSecurityManager();
   nsCOMPtr<nsIPrincipal> principal;
   if (secMan) {
     secMan->GetSystemPrincipal(getter_AddRefs(principal));
   }
   NS_ENSURE_STATE(principal);
   mPrincipal.swap(principal);
   // 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...
   nsCOMPtr<nsIGlobalObject> global = xpc::GetJunkScopeGlobal();
   NS_ENSURE_TRUE(global, NS_ERROR_FAILURE);
   BindToOwner(global);
   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 nsIJSNativeInitializer owner");
     aRv.Throw(NS_ERROR_FAILURE);
     return nullptr;
   }
   fileReader->BindToOwner(owner);
   // This object is bound to a |window|,
   // so reset the principal.
   nsCOMPtr<nsIScriptObjectPrincipal> scriptPrincipal = do_QueryInterface(owner);
   if (!scriptPrincipal) {
     aRv.Throw(NS_ERROR_FAILURE);
     return nullptr;
   }
   fileReader->mPrincipal = scriptPrincipal->GetPrincipal();
   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* aFile, JSContext* aCx)
 {
   NS_ENSURE_TRUE(aFile, NS_ERROR_NULL_POINTER);
   ErrorResult rv;
   ReadAsArrayBuffer(aCx, aFile, rv);
   return rv.ErrorCode();
 }
 NS_IMETHODIMP
 nsDOMFileReader::ReadAsBinaryString(nsIDOMBlob* aFile)
 {
   NS_ENSURE_TRUE(aFile, NS_ERROR_NULL_POINTER);
   ErrorResult rv;
   ReadAsBinaryString(aFile, rv);
   return rv.ErrorCode();
 }
 NS_IMETHODIMP
 nsDOMFileReader::ReadAsText(nsIDOMBlob* aFile,
                             const nsAString &aCharset)
 {
   NS_ENSURE_TRUE(aFile, NS_ERROR_NULL_POINTER);
   ErrorResult rv;
   ReadAsText(aFile, aCharset, rv);
   return rv.ErrorCode();
 }
 NS_IMETHODIMP
 nsDOMFileReader::ReadAsDataURL(nsIDOMBlob* aFile)
 {
   NS_ENSURE_TRUE(aFile, NS_ERROR_NULL_POINTER);
   ErrorResult rv;
   ReadAsDataURL(aFile, rv);
   return rv.ErrorCode();
 }
 NS_IMETHODIMP
 nsDOMFileReader::Abort()
 {
   ErrorResult rv;
   FileIOObject::Abort(rv);
   return rv.ErrorCode();
 }
 /* virtual */ void
 nsDOMFileReader::DoAbort(nsAString& aEvent)
 {
   // Revert status and result attributes
   SetDOMStringToNull(mResult);
   mResultArrayBuffer = nullptr;
   // Non-null channel indicates a read is currently active
   if (mChannel) {
     // Cancel request requires an error status
     mChannel->Cancel(NS_ERROR_FAILURE);
     mChannel = nullptr;
   }
   mFile = 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::DoOnDataAvailable(nsIRequest *aRequest,
                                    nsISupports *aContext,
                                    nsIInputStream *aInputStream,
                                    uint64_t aOffset,
                                    uint32_t aCount)
 {
   if (mDataFormat == FILE_AS_BINARY) {
     //Continuously update our binary string as data comes in
     NS_ASSERTION(mResult.Length() == aOffset,
                  "unexpected mResult length");
     uint32_t oldLen = 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_t());
     NS_ENSURE_TRUE(buf, NS_ERROR_OUT_OF_MEMORY);
     uint32_t bytesRead = 0;
     aInputStream->ReadSegments(ReadFuncBinaryString, buf + oldLen, aCount,
                                &bytesRead);
     NS_ASSERTION(bytesRead == aCount, "failed to read data");
   }
   else if (mDataFormat == FILE_AS_ARRAYBUFFER) {
     uint32_t bytesRead = 0;
     aInputStream->Read((char*)JS_GetArrayBufferData(mResultArrayBuffer) + aOffset,
                        aCount, &bytesRead);
     NS_ASSERTION(bytesRead == aCount, "failed to read data");
   }
   else {
     //Update memory buffer to reflect the contents of the file
     if (aOffset + aCount > UINT32_MAX) {
       // PR_Realloc doesn't support over 4GB memory size even if 64-bit OS
       return NS_ERROR_OUT_OF_MEMORY;
     }
     mFileData = (char *)moz_realloc(mFileData, aOffset + aCount);
     NS_ENSURE_TRUE(mFileData, NS_ERROR_OUT_OF_MEMORY);
     uint32_t bytesRead = 0;
     aInputStream->Read(mFileData + aOffset, aCount, &bytesRead);
     NS_ASSERTION(bytesRead == aCount, "failed to read data");
     mDataLen += aCount;
   }
   return NS_OK;
 }
 nsresult
 nsDOMFileReader::DoOnStopRequest(nsIRequest *aRequest,
                                  nsISupports *aContext,
                                  nsresult aStatus,
                                  nsAString& aSuccessEvent,
                                  nsAString& aTerminationEvent)
 {
   // Make sure we drop all the objects that could hold files open now.
   nsCOMPtr<nsIChannel> channel;
   mChannel.swap(channel);
   nsCOMPtr<nsIDOMBlob> file;
   mFile.swap(file);
   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:
       break; //Already accumulated mResultArrayBuffer
     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(file, mCharset, "", mDataLen, mResult);
         break;
       }
       rv = GetAsText(file, mCharset, mFileData, mDataLen, mResult);
       break;
     case FILE_AS_DATAURL:
       rv = GetAsDataURL(file, mFileData, mDataLen, mResult);
       break;
   }
   mResult.SetIsVoid(false);
   FreeFileData();
   return rv;
 }
 // Helper methods
 void
 nsDOMFileReader::ReadFileContent(JSContext* aCx,
                                  nsIDOMBlob* aFile,
                                  const nsAString &aCharset,
                                  eDataFormat aDataFormat,
                                  ErrorResult& aRv)
 {
   MOZ_ASSERT(aFile);
   //Implicit abort to clear any other activity going on
   Abort();
   mError = nullptr;
   SetDOMStringToNull(mResult);
   mTransferred = 0;
   mTotal = 0;
   mReadyState = nsIDOMFileReader::EMPTY;
   FreeFileData();
   mFile = aFile;
   mDataFormat = aDataFormat;
   CopyUTF16toUTF8(aCharset, mCharset);
   //Establish a channel with our file
   {
     // Hold the internal URL alive only as long as necessary
     // After the channel is created it will own whatever is backing
     // the DOMFile.
     nsDOMFileInternalUrlHolder urlHolder(mFile, mPrincipal);
     nsCOMPtr<nsIURI> uri;
     aRv = NS_NewURI(getter_AddRefs(uri), urlHolder.mUrl);
     NS_ENSURE_SUCCESS_VOID(aRv.ErrorCode());
     nsCOMPtr<nsILoadGroup> loadGroup;
     if (HasOrHasHadOwner()) {
       if (!GetOwner()) {
         aRv.Throw(NS_ERROR_FAILURE);
         return;
       }
       nsIDocument* doc = GetOwner()->GetExtantDoc();
       if (doc) {
         loadGroup = doc->GetDocumentLoadGroup();
       }
     }
     aRv = NS_NewChannel(getter_AddRefs(mChannel), uri, nullptr, loadGroup,
                         nullptr, nsIRequest::LOAD_BACKGROUND);
     NS_ENSURE_SUCCESS_VOID(aRv.ErrorCode());
   }
   //Obtain the total size of the file before reading
   mTotal = mozilla::dom::kUnknownSize;
   mFile->GetSize(&mTotal);
   aRv = mChannel->AsyncOpen(this, nullptr);
   NS_ENSURE_SUCCESS_VOID(aRv.ErrorCode());
   //FileReader should be in loading state here
   mReadyState = nsIDOMFileReader::LOADING;
   DispatchProgressEvent(NS_LITERAL_STRING(LOADSTART_STR));
   if (mDataFormat == FILE_AS_ARRAYBUFFER) {
     RootResultArrayBuffer();
     mResultArrayBuffer = JS_NewArrayBuffer(aCx, mTotal);
     if (!mResultArrayBuffer) {
       NS_WARNING("Failed to create JS array buffer");
       aRv.Throw(NS_ERROR_FAILURE);
     }
   }
 }
 nsresult
 nsDOMFileReader::GetAsText(nsIDOMBlob *aFile,
                            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;
       aFile->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(nsIDOMBlob *aFile,
                               const char *aFileData,
                               uint32_t aDataLen,
                               nsAString& aResult)
 {
   aResult.AssignLiteral("data:");
   nsresult rv;
   nsString contentType;
   rv = aFile->GetType(contentType);
   if (NS_SUCCEEDED(rv) && !contentType.IsEmpty()) {
     aResult.Append(contentType);
   } else {
     aResult.AppendLiteral("application/octet-stream");
   }
   aResult.AppendLiteral(";base64,");
   nsCString encodedData;
   rv = Base64Encode(Substring(aFileData, aDataLen), encodedData);
   NS_ENSURE_SUCCESS(rv, rv);
   if (!AppendASCIItoUTF16(encodedData, aResult, fallible_t())) {
     return NS_ERROR_OUT_OF_MEMORY;
   }
   return NS_OK;
 }
 /* virtual */ JSObject*
 nsDOMFileReader::WrapObject(JSContext* aCx)
 {
   return FileReaderBinding::Wrap(aCx, this);
 }

The Tor Browser / annotate

content/base/src/nsDOMFileReader.cpp@6474c204b198 (annotated)

content/base/src/nsDOMFileReader.cpp