The Tor Browser: rdf/base/src/nsRDFXMLDataSource.cpp@b8a032363ba2 (annotated)

rdf/base/src/nsRDFXMLDataSource.cpp@b8a032363ba2 (annotated)

rdf/base/src/nsRDFXMLDataSource.cpp

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
 /* 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/. */
 /*
   A data source that can read itself from and write itself to an
   RDF/XML stream.
   For more information on the RDF/XML syntax,
   see http://www.w3.org/TR/REC-rdf-syntax/.
   This code is based on the final W3C Recommendation,
   http://www.w3.org/TR/1999/REC-rdf-syntax-19990222.
   TO DO
   -----
 ) Right now, the only kind of stream data sources that are _really_
      writable are "file:" URIs. (In fact, _all_ "file:" URIs are
      writable, modulo file system permissions; this may lead to some
      surprising behavior.) Eventually, it'd be great if we could open
      an arbitrary nsIOutputStream on *any* URL, and Netlib could just
      do the magic.
 ) Implement a more terse output for "typed" nodes; that is, instead
      of "RDF:Description type='ns:foo'", just output "ns:foo".
 ) When re-serializing, we "cheat" for Descriptions that talk about
      inline resources (i.e.., using the `ID' attribute specified in
      [6.21]). Instead of writing an `ID="foo"' for the first instance,
      and then `about="#foo"' for each subsequent instance, we just
      _always_ write `about="#foo"'.
      We do this so that we can handle the case where an RDF container
      has been assigned arbitrary properties: the spec says we can't
      dangle the attributes directly off the container, so we need to
      refer to it. Of course, with a little cleverness, we could fix
      this. But who cares?
 ) When re-serializing containers. We have to cheat on some
      containers, and use an illegal "about=" construct. We do this to
      handle containers that have been assigned URIs outside of the
      local document.
   Logging
   -------
   To turn on logging for this module, set
     NSPR_LOG_MODULES=nsRDFXMLDataSource:5
  */
 #include "nsIFileStreams.h"
 #include "nsIOutputStream.h"
 #include "nsIFile.h"
 #include "nsIFileChannel.h"
 #include "nsIDTD.h"
 #include "nsIRDFPurgeableDataSource.h"
 #include "nsIInputStream.h"
 #include "nsIOutputStream.h"
 #include "nsIRDFContainerUtils.h"
 #include "nsIRDFNode.h"
 #include "nsIRDFRemoteDataSource.h"
 #include "nsIRDFService.h"
 #include "nsIRDFXMLParser.h"
 #include "nsIRDFXMLSerializer.h"
 #include "nsIRDFXMLSink.h"
 #include "nsIRDFXMLSource.h"
 #include "nsIServiceManager.h"
 #include "nsIStreamListener.h"
 #include "nsIURL.h"
 #include "nsIFileURL.h"
 #include "nsNetUtil.h"
 #include "nsIChannel.h"
 #include "nsRDFCID.h"
 #include "nsRDFBaseDataSources.h"
 #include "nsCOMArray.h"
 #include "nsXPIDLString.h"
 #include "plstr.h"
 #include "prio.h"
 #include "prthread.h"
 #include "rdf.h"
 #include "rdfutil.h"
 #include "prlog.h"
 #include "nsNameSpaceMap.h"
 #include "nsCRT.h"
 #include "nsCycleCollectionParticipant.h"
 #include "nsIScriptSecurityManager.h"
 #include "nsIChannelEventSink.h"
 #include "nsIAsyncVerifyRedirectCallback.h"
 #include "nsNetUtil.h"
 #include "rdfIDataSource.h"
 //----------------------------------------------------------------------
 //
 // RDFXMLDataSourceImpl
 //
 class RDFXMLDataSourceImpl : public nsIRDFDataSource,
                              public nsIRDFRemoteDataSource,
                              public nsIRDFXMLSink,
                              public nsIRDFXMLSource,
                              public nsIStreamListener,
                              public rdfIDataSource,
                              public nsIInterfaceRequestor,
                              public nsIChannelEventSink
 {
 protected:
     enum LoadState {
         eLoadState_Unloaded,
         eLoadState_Pending,
         eLoadState_Loading,
         eLoadState_Loaded
     };
     nsCOMPtr<nsIRDFDataSource> mInner;
     bool                mIsWritable;    // true if the document can be written back
     bool                mIsDirty;       // true if the document should be written back
     LoadState           mLoadState;     // what we're doing now
     nsCOMArray<nsIRDFXMLSinkObserver> mObservers;
     nsCOMPtr<nsIURI>    mURL;
     nsCOMPtr<nsIStreamListener> mListener;
     nsNameSpaceMap      mNameSpaces;
     // pseudo-constants
     static int32_t gRefCnt;
     static nsIRDFService* gRDFService;
 #ifdef PR_LOGGING
     static PRLogModuleInfo* gLog;
 #endif
     nsresult Init();
     RDFXMLDataSourceImpl(void);
     virtual ~RDFXMLDataSourceImpl(void);
     nsresult rdfXMLFlush(nsIURI *aURI);
     friend nsresult
     NS_NewRDFXMLDataSource(nsIRDFDataSource** aResult);
     inline bool IsLoading() {
         return (mLoadState == eLoadState_Pending) ||
                (mLoadState == eLoadState_Loading);
     }
 public:
     // nsISupports
     NS_DECL_CYCLE_COLLECTING_ISUPPORTS
     NS_DECL_CYCLE_COLLECTION_CLASS_AMBIGUOUS(RDFXMLDataSourceImpl,
                                              nsIRDFDataSource)
     // nsIRDFDataSource
     NS_IMETHOD GetURI(char* *uri);
     NS_IMETHOD GetSource(nsIRDFResource* property,
                          nsIRDFNode* target,
                          bool tv,
                          nsIRDFResource** source) {
         return mInner->GetSource(property, target, tv, source);
     }
     NS_IMETHOD GetSources(nsIRDFResource* property,
                           nsIRDFNode* target,
                           bool tv,
                           nsISimpleEnumerator** sources) {
         return mInner->GetSources(property, target, tv, sources);
     }
     NS_IMETHOD GetTarget(nsIRDFResource* source,
                          nsIRDFResource* property,
                          bool tv,
                          nsIRDFNode** target) {
         return mInner->GetTarget(source, property, tv, target);
     }
     NS_IMETHOD GetTargets(nsIRDFResource* source,
                           nsIRDFResource* property,
                           bool tv,
                           nsISimpleEnumerator** targets) {
         return mInner->GetTargets(source, property, tv, targets);
     }
     NS_IMETHOD Assert(nsIRDFResource* aSource,
                       nsIRDFResource* aProperty,
                       nsIRDFNode* aTarget,
                       bool tv);
     NS_IMETHOD Unassert(nsIRDFResource* source,
                         nsIRDFResource* property,
                         nsIRDFNode* target);
     NS_IMETHOD Change(nsIRDFResource* aSource,
                       nsIRDFResource* aProperty,
                       nsIRDFNode* aOldTarget,
                       nsIRDFNode* aNewTarget);
     NS_IMETHOD Move(nsIRDFResource* aOldSource,
                     nsIRDFResource* aNewSource,
                     nsIRDFResource* aProperty,
                     nsIRDFNode* aTarget);
     NS_IMETHOD HasAssertion(nsIRDFResource* source,
                             nsIRDFResource* property,
                             nsIRDFNode* target,
                             bool tv,
                             bool* hasAssertion) {
         return mInner->HasAssertion(source, property, target, tv, hasAssertion);
     }
     NS_IMETHOD AddObserver(nsIRDFObserver* aObserver) {
         return mInner->AddObserver(aObserver);
     }
     NS_IMETHOD RemoveObserver(nsIRDFObserver* aObserver) {
         return mInner->RemoveObserver(aObserver);
     }
     NS_IMETHOD HasArcIn(nsIRDFNode *aNode, nsIRDFResource *aArc, bool *_retval) {
         return mInner->HasArcIn(aNode, aArc, _retval);
     }
     NS_IMETHOD HasArcOut(nsIRDFResource *aSource, nsIRDFResource *aArc, bool *_retval) {
         return mInner->HasArcOut(aSource, aArc, _retval);
     }
     NS_IMETHOD ArcLabelsIn(nsIRDFNode* node,
                            nsISimpleEnumerator** labels) {
         return mInner->ArcLabelsIn(node, labels);
     }
     NS_IMETHOD ArcLabelsOut(nsIRDFResource* source,
                             nsISimpleEnumerator** labels) {
         return mInner->ArcLabelsOut(source, labels);
     }
     NS_IMETHOD GetAllResources(nsISimpleEnumerator** aResult) {
         return mInner->GetAllResources(aResult);
     }
     NS_IMETHOD GetAllCmds(nsIRDFResource* source,
                               nsISimpleEnumerator/*<nsIRDFResource>*/** commands) {
         return mInner->GetAllCmds(source, commands);
     }
     NS_IMETHOD IsCommandEnabled(nsISupportsArray/*<nsIRDFResource>*/* aSources,
                                 nsIRDFResource*   aCommand,
                                 nsISupportsArray/*<nsIRDFResource>*/* aArguments,
                                 bool* aResult) {
         return mInner->IsCommandEnabled(aSources, aCommand, aArguments, aResult);
     }
     NS_IMETHOD DoCommand(nsISupportsArray/*<nsIRDFResource>*/* aSources,
                          nsIRDFResource*   aCommand,
                          nsISupportsArray/*<nsIRDFResource>*/* aArguments) {
         // XXX Uh oh, this could cause problems wrt. the "dirty" flag
         // if it changes the in-memory store's internal state.
         return mInner->DoCommand(aSources, aCommand, aArguments);
     }
     NS_IMETHOD BeginUpdateBatch() {
         return mInner->BeginUpdateBatch();
     }
     NS_IMETHOD EndUpdateBatch() {
         return mInner->EndUpdateBatch();
     }
     // nsIRDFRemoteDataSource interface
     NS_DECL_NSIRDFREMOTEDATASOURCE
     // nsIRDFXMLSink interface
     NS_DECL_NSIRDFXMLSINK
     // nsIRDFXMLSource interface
     NS_DECL_NSIRDFXMLSOURCE
     // nsIRequestObserver
     NS_DECL_NSIREQUESTOBSERVER
     // nsIStreamListener
     NS_DECL_NSISTREAMLISTENER
     // nsIInterfaceRequestor
     NS_DECL_NSIINTERFACEREQUESTOR
     // nsIChannelEventSink
     NS_DECL_NSICHANNELEVENTSINK
     // rdfIDataSource
     NS_IMETHOD VisitAllSubjects(rdfITripleVisitor *aVisitor) {
         nsresult rv;
         nsCOMPtr<rdfIDataSource> rdfds = do_QueryInterface(mInner, &rv);
         if (NS_FAILED(rv)) return rv;
         return rdfds->VisitAllSubjects(aVisitor);
     }
     NS_IMETHOD VisitAllTriples(rdfITripleVisitor *aVisitor) {
         nsresult rv;
         nsCOMPtr<rdfIDataSource> rdfds = do_QueryInterface(mInner, &rv);
         if (NS_FAILED(rv)) return rv;
         return rdfds->VisitAllTriples(aVisitor);
     }
     // Implementation methods
     bool
     MakeQName(nsIRDFResource* aResource,
               nsString& property,
               nsString& nameSpacePrefix,
               nsString& nameSpaceURI);
     nsresult
     SerializeAssertion(nsIOutputStream* aStream,
                        nsIRDFResource* aResource,
                        nsIRDFResource* aProperty,
                        nsIRDFNode* aValue);
     nsresult
     SerializeProperty(nsIOutputStream* aStream,
                       nsIRDFResource* aResource,
                       nsIRDFResource* aProperty);
     bool
     IsContainerProperty(nsIRDFResource* aProperty);
     nsresult
     SerializeDescription(nsIOutputStream* aStream,
                          nsIRDFResource* aResource);
     nsresult
     SerializeMember(nsIOutputStream* aStream,
                     nsIRDFResource* aContainer,
                     nsIRDFNode* aMember);
     nsresult
     SerializeContainer(nsIOutputStream* aStream,
                        nsIRDFResource* aContainer);
     nsresult
     SerializePrologue(nsIOutputStream* aStream);
     nsresult
     SerializeEpilogue(nsIOutputStream* aStream);
     bool
     IsA(nsIRDFDataSource* aDataSource, nsIRDFResource* aResource, nsIRDFResource* aType);
 protected:
     nsresult
     BlockingParse(nsIURI* aURL, nsIStreamListener* aConsumer);
 };
 int32_t         RDFXMLDataSourceImpl::gRefCnt = 0;
 nsIRDFService*  RDFXMLDataSourceImpl::gRDFService;
 #ifdef PR_LOGGING
 PRLogModuleInfo* RDFXMLDataSourceImpl::gLog;
 #endif
 static const char kFileURIPrefix[] = "file:";
 static const char kResourceURIPrefix[] = "resource:";
 //----------------------------------------------------------------------
 nsresult
 NS_NewRDFXMLDataSource(nsIRDFDataSource** aResult)
 {
     NS_PRECONDITION(aResult != nullptr, "null ptr");
     if (! aResult)
         return NS_ERROR_NULL_POINTER;
     RDFXMLDataSourceImpl* datasource = new RDFXMLDataSourceImpl();
     if (! datasource)
         return NS_ERROR_OUT_OF_MEMORY;
     nsresult rv;
     rv = datasource->Init();
     if (NS_FAILED(rv)) {
         delete datasource;
         return rv;
     }
     NS_ADDREF(datasource);
     *aResult = datasource;
     return NS_OK;
 }
 RDFXMLDataSourceImpl::RDFXMLDataSourceImpl(void)
     : mIsWritable(true),
       mIsDirty(false),
       mLoadState(eLoadState_Unloaded)
 {
 #ifdef PR_LOGGING
     if (! gLog)
         gLog = PR_NewLogModule("nsRDFXMLDataSource");
 #endif
 }
 nsresult
 RDFXMLDataSourceImpl::Init()
 {
     nsresult rv;
     NS_DEFINE_CID(kRDFInMemoryDataSourceCID, NS_RDFINMEMORYDATASOURCE_CID);
     mInner = do_CreateInstance(kRDFInMemoryDataSourceCID, &rv);
     if (NS_FAILED(rv)) return rv;
     if (gRefCnt++ == 0) {
         NS_DEFINE_CID(kRDFServiceCID, NS_RDFSERVICE_CID);
         rv = CallGetService(kRDFServiceCID, &gRDFService);
         NS_ASSERTION(NS_SUCCEEDED(rv), "unable to get RDF service");
         if (NS_FAILED(rv)) return rv;
     }
     return NS_OK;
 }
 RDFXMLDataSourceImpl::~RDFXMLDataSourceImpl(void)
 {
     // Unregister first so that nobody else tries to get us.
     (void) gRDFService->UnregisterDataSource(this);
     // Now flush contents
     (void) Flush();
     // Release RDF/XML sink observers
     mObservers.Clear();
     if (--gRefCnt == 0)
         NS_IF_RELEASE(gRDFService);
 }
 NS_IMPL_CYCLE_COLLECTION_CLASS(RDFXMLDataSourceImpl)
 NS_IMPL_CYCLE_COLLECTION_UNLINK_0(RDFXMLDataSourceImpl)
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(RDFXMLDataSourceImpl)
     NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mInner)
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
 NS_IMPL_CYCLE_COLLECTING_ADDREF(RDFXMLDataSourceImpl)
 NS_IMPL_CYCLE_COLLECTING_RELEASE(RDFXMLDataSourceImpl)
 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(RDFXMLDataSourceImpl)
     NS_INTERFACE_MAP_ENTRY(nsIRDFDataSource)
     NS_INTERFACE_MAP_ENTRY(nsIRDFRemoteDataSource)
     NS_INTERFACE_MAP_ENTRY(nsIRDFXMLSink)
     NS_INTERFACE_MAP_ENTRY(nsIRDFXMLSource)
     NS_INTERFACE_MAP_ENTRY(nsIRequestObserver)
     NS_INTERFACE_MAP_ENTRY(nsIStreamListener)
     NS_INTERFACE_MAP_ENTRY(rdfIDataSource)
     NS_INTERFACE_MAP_ENTRY(nsIInterfaceRequestor)
     NS_INTERFACE_MAP_ENTRY(nsIChannelEventSink)
     NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIRDFDataSource)
 NS_INTERFACE_MAP_END
 // nsIInterfaceRequestor
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::GetInterface(const nsIID& aIID, void** aSink)
 {
   return QueryInterface(aIID, aSink);
 }
 nsresult
 RDFXMLDataSourceImpl::BlockingParse(nsIURI* aURL, nsIStreamListener* aConsumer)
 {
     nsresult rv;
     // XXX I really hate the way that we're spoon-feeding this stuff
     // to the parser: it seems like this is something that netlib
     // should be able to do by itself.
     nsCOMPtr<nsIChannel> channel;
     nsCOMPtr<nsIRequest> request;
     // Null LoadGroup ?
     rv = NS_NewChannel(getter_AddRefs(channel), aURL, nullptr);
     if (NS_FAILED(rv)) return rv;
     nsCOMPtr<nsIInputStream> in;
     rv = channel->Open(getter_AddRefs(in));
     // Report success if the file doesn't exist, but propagate other errors.
     if (rv == NS_ERROR_FILE_NOT_FOUND) return NS_OK;
     if (NS_FAILED(rv)) return rv;
     if (! in) {
         NS_ERROR("no input stream");
         return NS_ERROR_FAILURE;
     }
     // Wrap the channel's input stream in a buffered stream to ensure that
     // ReadSegments is implemented (which OnDataAvailable expects).
     nsCOMPtr<nsIInputStream> bufStream;
     rv = NS_NewBufferedInputStream(getter_AddRefs(bufStream), in,
 /* buffer size */);
     if (NS_FAILED(rv)) return rv;
     // Notify load observers
     int32_t i;
     for (i = mObservers.Count() - 1; i >= 0; --i) {
         // Make sure to hold a strong reference to the observer so
         // that it doesn't go away in this call if it removes itself
         // as an observer
         nsCOMPtr<nsIRDFXMLSinkObserver> obs = mObservers[i];
         if (obs) {
             obs->OnBeginLoad(this);
         }
     }
     rv = aConsumer->OnStartRequest(channel, nullptr);
     uint64_t offset = 0;
     while (NS_SUCCEEDED(rv)) {
         // Skip ODA if the channel is canceled
         channel->GetStatus(&rv);
         if (NS_FAILED(rv))
             break;
         uint64_t avail;
         if (NS_FAILED(rv = bufStream->Available(&avail)))
             break; // error
         if (avail == 0)
             break; // eof
         if (avail > UINT32_MAX)
             avail = UINT32_MAX;
         rv = aConsumer->OnDataAvailable(channel, nullptr, bufStream, offset, (uint32_t)avail);
         if (NS_SUCCEEDED(rv))
             offset += avail;
     }
     if (NS_FAILED(rv))
         channel->Cancel(rv);
     channel->GetStatus(&rv);
     aConsumer->OnStopRequest(channel, nullptr, rv);
     // Notify load observers
     for (i = mObservers.Count() - 1; i >= 0; --i) {
         // Make sure to hold a strong reference to the observer so
         // that it doesn't go away in this call if it removes itself
         // as an observer
         nsCOMPtr<nsIRDFXMLSinkObserver> obs = mObservers[i];
         if (obs) {
             if (NS_FAILED(rv))
                 obs->OnError(this, rv, nullptr);
             obs->OnEndLoad(this);
         }
     }
     return rv;
 }
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::GetLoaded(bool* _result)
 {
     *_result = (mLoadState == eLoadState_Loaded);
     return NS_OK;
 }
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::Init(const char* uri)
 {
     NS_PRECONDITION(mInner != nullptr, "not initialized");
     if (! mInner)
         return NS_ERROR_OUT_OF_MEMORY;
     nsresult rv;
     rv = NS_NewURI(getter_AddRefs(mURL), nsDependentCString(uri));
     if (NS_FAILED(rv)) return rv;
     // XXX this is a hack: any "file:" URI is considered writable. All
     // others are considered read-only.
     if ((PL_strncmp(uri, kFileURIPrefix, sizeof(kFileURIPrefix) - 1) != 0) &&
         (PL_strncmp(uri, kResourceURIPrefix, sizeof(kResourceURIPrefix) - 1) != 0)) {
         mIsWritable = false;
     }
     rv = gRDFService->RegisterDataSource(this, false);
     if (NS_FAILED(rv)) return rv;
     return NS_OK;
 }
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::GetURI(char* *aURI)
 {
     *aURI = nullptr;
     if (!mURL) {
         return NS_OK;
     }
     nsAutoCString spec;
     mURL->GetSpec(spec);
     *aURI = ToNewCString(spec);
     if (!*aURI) {
         return NS_ERROR_OUT_OF_MEMORY;
     }
     return NS_OK;
 }
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::Assert(nsIRDFResource* aSource,
                              nsIRDFResource* aProperty,
                              nsIRDFNode* aTarget,
                              bool aTruthValue)
 {
     // We don't accept assertions unless we're writable (except in the
     // case that we're actually _reading_ the datasource in).
     nsresult rv;
     if (IsLoading()) {
         bool hasAssertion = false;
         nsCOMPtr<nsIRDFPurgeableDataSource> gcable = do_QueryInterface(mInner);
         if (gcable) {
             rv = gcable->Mark(aSource, aProperty, aTarget, aTruthValue, &hasAssertion);
             if (NS_FAILED(rv)) return rv;
         }
         rv = NS_RDF_ASSERTION_ACCEPTED;
         if (! hasAssertion) {
             rv = mInner->Assert(aSource, aProperty, aTarget, aTruthValue);
             if (NS_SUCCEEDED(rv) && gcable) {
                 // Now mark the new assertion, so it doesn't get
                 // removed when we sweep. Ignore rv, because we want
                 // to return what mInner->Assert() gave us.
                 bool didMark;
                 (void) gcable->Mark(aSource, aProperty, aTarget, aTruthValue, &didMark);
             }
             if (NS_FAILED(rv)) return rv;
         }
         return rv;
     }
     else if (mIsWritable) {
         rv = mInner->Assert(aSource, aProperty, aTarget, aTruthValue);
         if (rv == NS_RDF_ASSERTION_ACCEPTED)
             mIsDirty = true;
         return rv;
     }
     else {
         return NS_RDF_ASSERTION_REJECTED;
     }
 }
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::Unassert(nsIRDFResource* source,
                                nsIRDFResource* property,
                                nsIRDFNode* target)
 {
     // We don't accept assertions unless we're writable (except in the
     // case that we're actually _reading_ the datasource in).
     nsresult rv;
     if (IsLoading() || mIsWritable) {
         rv = mInner->Unassert(source, property, target);
         if (!IsLoading() && rv == NS_RDF_ASSERTION_ACCEPTED)
             mIsDirty = true;
     }
     else {
         rv = NS_RDF_ASSERTION_REJECTED;
     }
     return rv;
 }
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::Change(nsIRDFResource* aSource,
                              nsIRDFResource* aProperty,
                              nsIRDFNode* aOldTarget,
                              nsIRDFNode* aNewTarget)
 {
     nsresult rv;
     if (IsLoading() || mIsWritable) {
         rv = mInner->Change(aSource, aProperty, aOldTarget, aNewTarget);
         if (!IsLoading() && rv == NS_RDF_ASSERTION_ACCEPTED)
             mIsDirty = true;
     }
     else {
         rv = NS_RDF_ASSERTION_REJECTED;
     }
     return rv;
 }
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::Move(nsIRDFResource* aOldSource,
                            nsIRDFResource* aNewSource,
                            nsIRDFResource* aProperty,
                            nsIRDFNode* aTarget)
 {
     nsresult rv;
     if (IsLoading() || mIsWritable) {
         rv = mInner->Move(aOldSource, aNewSource, aProperty, aTarget);
         if (!IsLoading() && rv == NS_RDF_ASSERTION_ACCEPTED)
             mIsDirty = true;
     }
     else {
         rv = NS_RDF_ASSERTION_REJECTED;
     }
     return rv;
 }
 nsresult
 RDFXMLDataSourceImpl::rdfXMLFlush(nsIURI *aURI)
 {
     nsresult rv;
     {
         // Quick and dirty check to see if we're in XPCOM shutdown. If
         // we are, we're screwed: it's too late to serialize because
         // many of the services that we'll need to acquire to properly
         // write the file will be unaquirable.
         NS_DEFINE_CID(kRDFServiceCID, NS_RDFSERVICE_CID);
         nsCOMPtr<nsIRDFService> dummy = do_GetService(kRDFServiceCID, &rv);
         if (NS_FAILED(rv)) {
             NS_WARNING("unable to Flush() dirty datasource during XPCOM shutdown");
             return rv;
         }
     }
     // Is it a file? If so, we can write to it. Some day, it'd be nice
     // if we didn't care what kind of stream this was...
     nsCOMPtr<nsIFileURL> fileURL = do_QueryInterface(aURI);
     if (fileURL) {
         nsCOMPtr<nsIFile> file;
         fileURL->GetFile(getter_AddRefs(file));
         if (file) {
             // get a safe output stream, so we don't clobber the datasource file unless
             // all the writes succeeded.
             nsCOMPtr<nsIOutputStream> out;
             rv = NS_NewSafeLocalFileOutputStream(getter_AddRefs(out),
                                                  file,
                                                  PR_WRONLY | PR_CREATE_FILE,
                                                  /*octal*/ 0666,
 );
             if (NS_FAILED(rv)) return rv;
             nsCOMPtr<nsIOutputStream> bufferedOut;
             rv = NS_NewBufferedOutputStream(getter_AddRefs(bufferedOut), out, 4096);
             if (NS_FAILED(rv)) return rv;
             rv = Serialize(bufferedOut);
             if (NS_FAILED(rv)) return rv;
             // All went ok. Maybe except for problems in Write(), but the stream detects
             // that for us
             nsCOMPtr<nsISafeOutputStream> safeStream = do_QueryInterface(bufferedOut, &rv);
             if (NS_FAILED(rv)) return rv;
             rv = safeStream->Finish();
             if (NS_FAILED(rv)) {
                 NS_WARNING("failed to save datasource file! possible dataloss");
                 return rv;
             }
         }
     }
     return NS_OK;
 }
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::FlushTo(const char *aURI)
 {
     NS_PRECONDITION(aURI != nullptr, "not initialized");
     if (!aURI)
         return NS_ERROR_NULL_POINTER;
     // XXX this is a hack: any "file:" URI is considered writable. All
     // others are considered read-only.
     if ((PL_strncmp(aURI, kFileURIPrefix, sizeof(kFileURIPrefix) - 1) != 0) &&
         (PL_strncmp(aURI, kResourceURIPrefix, sizeof(kResourceURIPrefix) - 1) != 0))
     {
         return NS_ERROR_ILLEGAL_VALUE;
     }
     nsCOMPtr<nsIURI>  url;
     nsresult rv = NS_NewURI(getter_AddRefs(url), aURI);
     if (NS_FAILED(rv))
       return rv;
     rv = rdfXMLFlush(url);
     return rv;
 }
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::Flush(void)
 {
     if (!mIsWritable || !mIsDirty)
         return NS_OK;
     // while it is not fatal if mURL is not set,
     // indicate failure since we can't flush back to an unknown origin
     if (! mURL)
         return NS_ERROR_NOT_INITIALIZED;
 #ifdef PR_LOGGING
     nsAutoCString spec;
     mURL->GetSpec(spec);
     PR_LOG(gLog, PR_LOG_NOTICE,
            ("rdfxml[%p] flush(%s)", this, spec.get()));
 #endif
     nsresult rv;
     if (NS_SUCCEEDED(rv = rdfXMLFlush(mURL)))
     {
       mIsDirty = false;
     }
     return rv;
 }
 //----------------------------------------------------------------------
 //
 // nsIRDFXMLDataSource methods
 //
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::GetReadOnly(bool* aIsReadOnly)
 {
     *aIsReadOnly = !mIsWritable;
     return NS_OK;
 }
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::SetReadOnly(bool aIsReadOnly)
 {
     if (mIsWritable && aIsReadOnly)
         mIsWritable = false;
     return NS_OK;
 }
 // nsIChannelEventSink
 // This code is copied from nsSameOriginChecker::OnChannelRedirect. See
 // bug 475940 on providing this code in a shared location.
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::AsyncOnChannelRedirect(nsIChannel *aOldChannel,
                                              nsIChannel *aNewChannel,
                                              uint32_t aFlags,
                                              nsIAsyncVerifyRedirectCallback *cb)
 {
     NS_PRECONDITION(aNewChannel, "Redirecting to null channel?");
     nsresult rv;
     nsCOMPtr<nsIScriptSecurityManager> secMan =
         do_GetService(NS_SCRIPTSECURITYMANAGER_CONTRACTID, &rv);
     NS_ENSURE_SUCCESS(rv, rv);
     nsCOMPtr<nsIPrincipal> oldPrincipal;
     secMan->GetChannelPrincipal(aOldChannel, getter_AddRefs(oldPrincipal));
     nsCOMPtr<nsIURI> newURI;
     aNewChannel->GetURI(getter_AddRefs(newURI));
     nsCOMPtr<nsIURI> newOriginalURI;
     aNewChannel->GetOriginalURI(getter_AddRefs(newOriginalURI));
     NS_ENSURE_STATE(oldPrincipal && newURI && newOriginalURI);
     rv = oldPrincipal->CheckMayLoad(newURI, false, false);
     if (NS_SUCCEEDED(rv) && newOriginalURI != newURI) {
         rv = oldPrincipal->CheckMayLoad(newOriginalURI, false, false);
     }
     if (NS_FAILED(rv))
         return rv;
     cb->OnRedirectVerifyCallback(NS_OK);
     return NS_OK;
 }
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::Refresh(bool aBlocking)
 {
 #ifdef PR_LOGGING
     nsAutoCString spec;
     if (mURL) {
         mURL->GetSpec(spec);
     }
     PR_LOG(gLog, PR_LOG_NOTICE,
            ("rdfxml[%p] refresh(%s) %sblocking", this, spec.get(), (aBlocking ? "" : "non")));
 #endif
     // If an asynchronous load is already pending, then just let it do
     // the honors.
     if (IsLoading()) {
         PR_LOG(gLog, PR_LOG_NOTICE,
                ("rdfxml[%p] refresh(%s) a load was pending", this, spec.get()));
         if (aBlocking) {
             NS_WARNING("blocking load requested when async load pending");
             return NS_ERROR_FAILURE;
         }
         else {
             return NS_OK;
         }
     }
     if (! mURL)
         return NS_ERROR_FAILURE;
     nsCOMPtr<nsIRDFXMLParser> parser = do_CreateInstance("@mozilla.org/rdf/xml-parser;1");
     if (! parser)
         return NS_ERROR_FAILURE;
     nsresult rv = parser->ParseAsync(this, mURL, getter_AddRefs(mListener));
     if (NS_FAILED(rv)) return rv;
     if (aBlocking) {
         rv = BlockingParse(mURL, this);
         mListener = nullptr; // release the parser
         if (NS_FAILED(rv)) return rv;
     }
     else {
         // Null LoadGroup ?
         rv = NS_OpenURI(this, nullptr, mURL, nullptr, nullptr, this);
         if (NS_FAILED(rv)) return rv;
         // So we don't try to issue two asynchronous loads at once.
         mLoadState = eLoadState_Pending;
     }
     return NS_OK;
 }
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::BeginLoad(void)
 {
 #ifdef PR_LOGGING
     nsAutoCString spec;
     if (mURL) {
         mURL->GetSpec(spec);
     }
     PR_LOG(gLog, PR_LOG_NOTICE,
            ("rdfxml[%p] begin-load(%s)", this, spec.get()));
 #endif
     mLoadState = eLoadState_Loading;
     for (int32_t i = mObservers.Count() - 1; i >= 0; --i) {
         // Make sure to hold a strong reference to the observer so
         // that it doesn't go away in this call if it removes itself
         // as an observer
         nsCOMPtr<nsIRDFXMLSinkObserver> obs = mObservers[i];
         if (obs) {
             obs->OnBeginLoad(this);
         }
     }
     return NS_OK;
 }
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::Interrupt(void)
 {
 #ifdef PR_LOGGING
     nsAutoCString spec;
     if (mURL) {
         mURL->GetSpec(spec);
     }
     PR_LOG(gLog, PR_LOG_NOTICE,
            ("rdfxml[%p] interrupt(%s)", this, spec.get()));
 #endif
     for (int32_t i = mObservers.Count() - 1; i >= 0; --i) {
         // Make sure to hold a strong reference to the observer so
         // that it doesn't go away in this call if it removes itself
         // as an observer
         nsCOMPtr<nsIRDFXMLSinkObserver> obs = mObservers[i];
         if (obs) {
             obs->OnInterrupt(this);
         }
     }
     return NS_OK;
 }
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::Resume(void)
 {
 #ifdef PR_LOGGING
     nsAutoCString spec;
     if (mURL) {
         mURL->GetSpec(spec);
     }
     PR_LOG(gLog, PR_LOG_NOTICE,
            ("rdfxml[%p] resume(%s)", this, spec.get()));
 #endif
     for (int32_t i = mObservers.Count() - 1; i >= 0; --i) {
         // Make sure to hold a strong reference to the observer so
         // that it doesn't go away in this call if it removes itself
         // as an observer
         nsCOMPtr<nsIRDFXMLSinkObserver> obs = mObservers[i];
         if (obs) {
             obs->OnResume(this);
         }
     }
     return NS_OK;
 }
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::EndLoad(void)
 {
 #ifdef PR_LOGGING
     nsAutoCString spec;
     if (mURL) {
         mURL->GetSpec(spec);
     }
     PR_LOG(gLog, PR_LOG_NOTICE,
            ("rdfxml[%p] end-load(%s)", this, spec.get()));
 #endif
     mLoadState = eLoadState_Loaded;
     // Clear out any unmarked assertions from the datasource.
     nsCOMPtr<nsIRDFPurgeableDataSource> gcable = do_QueryInterface(mInner);
     if (gcable) {
         gcable->Sweep();
     }
     // Notify load observers
     for (int32_t i = mObservers.Count() - 1; i >= 0; --i) {
         // Make sure to hold a strong reference to the observer so
         // that it doesn't go away in this call if it removes itself
         // as an observer
         nsCOMPtr<nsIRDFXMLSinkObserver> obs = mObservers[i];
         if (obs) {
             obs->OnEndLoad(this);
         }
     }
     return NS_OK;
 }
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::AddNameSpace(nsIAtom* aPrefix, const nsString& aURI)
 {
     mNameSpaces.Put(aURI, aPrefix);
     return NS_OK;
 }
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::AddXMLSinkObserver(nsIRDFXMLSinkObserver* aObserver)
 {
     if (! aObserver)
         return NS_ERROR_NULL_POINTER;
     mObservers.AppendObject(aObserver);
     return NS_OK;
 }
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::RemoveXMLSinkObserver(nsIRDFXMLSinkObserver* aObserver)
 {
     if (! aObserver)
         return NS_ERROR_NULL_POINTER;
     mObservers.RemoveObject(aObserver);
     return NS_OK;
 }
 //----------------------------------------------------------------------
 //
 // nsIRequestObserver
 //
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::OnStartRequest(nsIRequest *request, nsISupports *ctxt)
 {
     return mListener->OnStartRequest(request, ctxt);
 }
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::OnStopRequest(nsIRequest *request,
                                     nsISupports *ctxt,
                                     nsresult status)
 {
     if (NS_FAILED(status)) {
         for (int32_t i = mObservers.Count() - 1; i >= 0; --i) {
             // Make sure to hold a strong reference to the observer so
             // that it doesn't go away in this call if it removes
             // itself as an observer
             nsCOMPtr<nsIRDFXMLSinkObserver> obs = mObservers[i];
             if (obs) {
                 obs->OnError(this, status, nullptr);
             }
         }
     }
     nsresult rv;
     rv = mListener->OnStopRequest(request, ctxt, status);
     mListener = nullptr; // release the parser
     return rv;
 }
 //----------------------------------------------------------------------
 //
 // nsIStreamListener
 //
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::OnDataAvailable(nsIRequest *request,
                                       nsISupports *ctxt,
                                       nsIInputStream *inStr,
                                       uint64_t sourceOffset,
                                       uint32_t count)
 {
     return mListener->OnDataAvailable(request, ctxt, inStr, sourceOffset, count);
 }
 //----------------------------------------------------------------------
 //
 // nsIRDFXMLSource
 //
 NS_IMETHODIMP
 RDFXMLDataSourceImpl::Serialize(nsIOutputStream* aStream)
 {
     nsresult rv;
     nsCOMPtr<nsIRDFXMLSerializer> serializer
         = do_CreateInstance("@mozilla.org/rdf/xml-serializer;1", &rv);
     if (! serializer)
         return rv;
     rv = serializer->Init(this);
     if (NS_FAILED(rv)) return rv;
     // Add any namespace information that we picked up when reading
     // the RDF/XML
     nsNameSpaceMap::const_iterator last = mNameSpaces.last();
     for (nsNameSpaceMap::const_iterator iter = mNameSpaces.first();
          iter != last; ++iter) {
         // We might wanna change nsIRDFXMLSerializer to nsACString and
         // use a heap allocated buffer here in the future.
         NS_ConvertUTF8toUTF16 uri(iter->mURI);
         serializer->AddNameSpace(iter->mPrefix, uri);
     }
     // Serialize!
     nsCOMPtr<nsIRDFXMLSource> source = do_QueryInterface(serializer);
     if (! source)
         return NS_ERROR_FAILURE;
     return source->Serialize(aStream);
 }

The Tor Browser / annotate

rdf/base/src/nsRDFXMLDataSource.cpp@b8a032363ba2 (annotated)

rdf/base/src/nsRDFXMLDataSource.cpp