/* -*- 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/. * * * This Original Code has been modified by IBM Corporation. * Modifications made by IBM described herein are * Copyright (c) International Business Machines * Corporation, 2000 * * Modifications to Mozilla code or documentation * identified per MPL Section 3.3 * * Date Modified by Description of modification * 03/27/2000 IBM Corp. Added PR_CALLBACK for Optlink * use in OS2 */ /* Implementation for an in-memory RDF data store. TO DO 1) Instrument this code to gather space and time performance characteristics. 2) Optimize lookups for datasources which have a small number of properties + fanning out to a large number of targets. 3) Complete implementation of thread-safety; specifically, make assertions be reference counted objects (so that a cursor can still refer to an assertion that gets removed from the graph). */ #include "nsAgg.h" #include "nsCOMPtr.h" #include "nscore.h" #include "nsArrayEnumerator.h" #include "nsIOutputStream.h" #include "nsIRDFDataSource.h" #include "nsIRDFLiteral.h" #include "nsIRDFNode.h" #include "nsIRDFObserver.h" #include "nsIRDFInMemoryDataSource.h" #include "nsIRDFPropagatableDataSource.h" #include "nsIRDFPurgeableDataSource.h" #include "nsIRDFService.h" #include "nsIServiceManager.h" #include "nsISupportsArray.h" #include "nsCOMArray.h" #include "nsEnumeratorUtils.h" #include "nsTArray.h" #include "nsCRT.h" #include "nsRDFCID.h" #include "nsRDFBaseDataSources.h" #include "nsString.h" #include "nsReadableUtils.h" #include "nsXPIDLString.h" #include "rdfutil.h" #include "PLDHashTable.h" #include "plstr.h" #include "mozilla/Logging.h" #include "rdf.h" #include "rdfIDataSource.h" #include "rdfITripleVisitor.h" using mozilla::LogLevel; // This struct is used as the slot value in the forward and reverse // arcs hash tables. // // Assertion objects are reference counted, because each Assertion's // ownership is shared between the datasource and any enumerators that // are currently iterating over the datasource. // class Assertion { public: Assertion(nsIRDFResource* aSource, // normal assertion nsIRDFResource* aProperty, nsIRDFNode* aTarget, bool aTruthValue); explicit Assertion(nsIRDFResource* aSource); // PLDHashTable assertion variant private: ~Assertion(); public: void AddRef() { if (mRefCnt == UINT16_MAX) { NS_WARNING("refcount overflow, leaking Assertion"); return; } ++mRefCnt; } void Release() { if (mRefCnt == UINT16_MAX) { NS_WARNING("refcount overflow, leaking Assertion"); return; } if (--mRefCnt == 0) delete this; } // For nsIRDFPurgeableDataSource inline void Mark() { u.as.mMarked = true; } inline bool IsMarked() { return u.as.mMarked; } inline void Unmark() { u.as.mMarked = false; } // public for now, because I'm too lazy to go thru and clean this up. // These are shared between hash/as (see the union below) nsIRDFResource* mSource; Assertion* mNext; union { struct hash { PLDHashTable* mPropertyHash; } hash; struct as { nsIRDFResource* mProperty; nsIRDFNode* mTarget; Assertion* mInvNext; // make sure bool are final elements bool mTruthValue; bool mMarked; } as; } u; // also shared between hash/as (see the union above) // but placed after union definition to ensure that // all 32-bit entries are long aligned uint16_t mRefCnt; bool mHashEntry; }; struct Entry : PLDHashEntryHdr { nsIRDFNode* mNode; Assertion* mAssertions; }; Assertion::Assertion(nsIRDFResource* aSource) : mSource(aSource), mNext(nullptr), mRefCnt(0), mHashEntry(true) { MOZ_COUNT_CTOR(Assertion); NS_ADDREF(mSource); u.hash.mPropertyHash = new PLDHashTable(PLDHashTable::StubOps(), sizeof(Entry)); } Assertion::Assertion(nsIRDFResource* aSource, nsIRDFResource* aProperty, nsIRDFNode* aTarget, bool aTruthValue) : mSource(aSource), mNext(nullptr), mRefCnt(0), mHashEntry(false) { MOZ_COUNT_CTOR(Assertion); u.as.mProperty = aProperty; u.as.mTarget = aTarget; NS_ADDREF(mSource); NS_ADDREF(u.as.mProperty); NS_ADDREF(u.as.mTarget); u.as.mInvNext = nullptr; u.as.mTruthValue = aTruthValue; u.as.mMarked = false; } Assertion::~Assertion() { if (mHashEntry && u.hash.mPropertyHash) { for (auto i = u.hash.mPropertyHash->Iter(); !i.Done(); i.Next()) { auto entry = static_cast(i.Get()); Assertion* as = entry->mAssertions; while (as) { Assertion* doomed = as; as = as->mNext; // Unlink, and release the datasource's reference. doomed->mNext = doomed->u.as.mInvNext = nullptr; doomed->Release(); } } delete u.hash.mPropertyHash; u.hash.mPropertyHash = nullptr; } MOZ_COUNT_DTOR(Assertion); #ifdef DEBUG_REFS --gInstanceCount; fprintf(stdout, "%d - RDF: Assertion\n", gInstanceCount); #endif NS_RELEASE(mSource); if (!mHashEntry) { NS_RELEASE(u.as.mProperty); NS_RELEASE(u.as.mTarget); } } //////////////////////////////////////////////////////////////////////// // InMemoryDataSource class InMemoryArcsEnumeratorImpl; class InMemoryAssertionEnumeratorImpl; class InMemoryResourceEnumeratorImpl; class InMemoryDataSource : public nsIRDFDataSource, public nsIRDFInMemoryDataSource, public nsIRDFPropagatableDataSource, public nsIRDFPurgeableDataSource, public rdfIDataSource { protected: // These hash tables are keyed on pointers to nsIRDFResource // objects (the nsIRDFService ensures that there is only ever one // nsIRDFResource object per unique URI). The value of an entry is // an Assertion struct, which is a linked list of (subject // predicate object) triples. PLDHashTable mForwardArcs; PLDHashTable mReverseArcs; nsCOMArray mObservers; uint32_t mNumObservers; // VisitFoo needs to block writes, [Un]Assert only allowed // during mReadCount == 0 uint32_t mReadCount; friend class InMemoryArcsEnumeratorImpl; friend class InMemoryAssertionEnumeratorImpl; friend class InMemoryResourceEnumeratorImpl; // b/c it needs to enumerate mForwardArcs // Thread-safe writer implementation methods. nsresult LockedAssert(nsIRDFResource* source, nsIRDFResource* property, nsIRDFNode* target, bool tv); nsresult LockedUnassert(nsIRDFResource* source, nsIRDFResource* property, nsIRDFNode* target); explicit InMemoryDataSource(nsISupports* aOuter); virtual ~InMemoryDataSource(); friend nsresult NS_NewRDFInMemoryDataSource(nsISupports* aOuter, const nsIID& aIID, void** aResult); public: NS_DECL_CYCLE_COLLECTING_AGGREGATED NS_DECL_AGGREGATED_CYCLE_COLLECTION_CLASS(InMemoryDataSource) // nsIRDFDataSource methods NS_DECL_NSIRDFDATASOURCE // nsIRDFInMemoryDataSource methods NS_DECL_NSIRDFINMEMORYDATASOURCE // nsIRDFPropagatableDataSource methods NS_DECL_NSIRDFPROPAGATABLEDATASOURCE // nsIRDFPurgeableDataSource methods NS_DECL_NSIRDFPURGEABLEDATASOURCE // rdfIDataSource methods NS_DECL_RDFIDATASOURCE protected: struct SweepInfo { Assertion* mUnassertList; PLDHashTable* mReverseArcs; }; static void SweepForwardArcsEntries(PLDHashTable* aTable, SweepInfo* aArg); public: // Implementation methods Assertion* GetForwardArcs(nsIRDFResource* u) { PLDHashEntryHdr* hdr = mForwardArcs.Search(u); return hdr ? static_cast(hdr)->mAssertions : nullptr; } Assertion* GetReverseArcs(nsIRDFNode* v) { PLDHashEntryHdr* hdr = mReverseArcs.Search(v); return hdr ? static_cast(hdr)->mAssertions : nullptr; } void SetForwardArcs(nsIRDFResource* u, Assertion* as) { if (as) { auto entry = static_cast(mForwardArcs.Add(u, mozilla::fallible)); if (entry) { entry->mNode = u; entry->mAssertions = as; } } else { mForwardArcs.Remove(u); } } void SetReverseArcs(nsIRDFNode* v, Assertion* as) { if (as) { auto entry = static_cast(mReverseArcs.Add(v, mozilla::fallible)); if (entry) { entry->mNode = v; entry->mAssertions = as; } } else { mReverseArcs.Remove(v); } } void LogOperation(const char* aOperation, nsIRDFResource* asource, nsIRDFResource* aProperty, nsIRDFNode* aTarget, bool aTruthValue = true); bool mPropagateChanges; private: static PRLogModuleInfo* gLog; }; PRLogModuleInfo* InMemoryDataSource::gLog; //---------------------------------------------------------------------- // // InMemoryAssertionEnumeratorImpl // /** * InMemoryAssertionEnumeratorImpl */ class InMemoryAssertionEnumeratorImpl : public nsISimpleEnumerator { private: InMemoryDataSource* mDataSource; nsIRDFResource* mSource; nsIRDFResource* mProperty; nsIRDFNode* mTarget; nsIRDFNode* mValue; bool mTruthValue; Assertion* mNextAssertion; nsCOMPtr mHashArcs; virtual ~InMemoryAssertionEnumeratorImpl(); public: InMemoryAssertionEnumeratorImpl(InMemoryDataSource* aDataSource, nsIRDFResource* aSource, nsIRDFResource* aProperty, nsIRDFNode* aTarget, bool aTruthValue); // nsISupports interface NS_DECL_ISUPPORTS // nsISimpleEnumerator interface NS_DECL_NSISIMPLEENUMERATOR }; //////////////////////////////////////////////////////////////////////// InMemoryAssertionEnumeratorImpl::InMemoryAssertionEnumeratorImpl( InMemoryDataSource* aDataSource, nsIRDFResource* aSource, nsIRDFResource* aProperty, nsIRDFNode* aTarget, bool aTruthValue) : mDataSource(aDataSource), mSource(aSource), mProperty(aProperty), mTarget(aTarget), mValue(nullptr), mTruthValue(aTruthValue), mNextAssertion(nullptr) { NS_ADDREF(mDataSource); NS_IF_ADDREF(mSource); NS_ADDREF(mProperty); NS_IF_ADDREF(mTarget); if (mSource) { mNextAssertion = mDataSource->GetForwardArcs(mSource); if (mNextAssertion && mNextAssertion->mHashEntry) { // its our magical HASH_ENTRY forward hash for assertions PLDHashEntryHdr* hdr = mNextAssertion->u.hash.mPropertyHash->Search(aProperty); mNextAssertion = hdr ? static_cast(hdr)->mAssertions : nullptr; } } else { mNextAssertion = mDataSource->GetReverseArcs(mTarget); } // Add an owning reference from the enumerator if (mNextAssertion) mNextAssertion->AddRef(); } InMemoryAssertionEnumeratorImpl::~InMemoryAssertionEnumeratorImpl() { #ifdef DEBUG_REFS --gInstanceCount; fprintf(stdout, "%d - RDF: InMemoryAssertionEnumeratorImpl\n", gInstanceCount); #endif if (mNextAssertion) mNextAssertion->Release(); NS_IF_RELEASE(mDataSource); NS_IF_RELEASE(mSource); NS_IF_RELEASE(mProperty); NS_IF_RELEASE(mTarget); NS_IF_RELEASE(mValue); } NS_IMPL_ADDREF(InMemoryAssertionEnumeratorImpl) NS_IMPL_RELEASE(InMemoryAssertionEnumeratorImpl) NS_IMPL_QUERY_INTERFACE(InMemoryAssertionEnumeratorImpl, nsISimpleEnumerator) NS_IMETHODIMP InMemoryAssertionEnumeratorImpl::HasMoreElements(bool* aResult) { if (mValue) { *aResult = true; return NS_OK; } while (mNextAssertion) { bool foundIt = false; if ((mProperty == mNextAssertion->u.as.mProperty) && (mTruthValue == mNextAssertion->u.as.mTruthValue)) { if (mSource) { mValue = mNextAssertion->u.as.mTarget; NS_ADDREF(mValue); } else { mValue = mNextAssertion->mSource; NS_ADDREF(mValue); } foundIt = true; } // Remember the last assertion we were holding on to Assertion* as = mNextAssertion; // iterate mNextAssertion = (mSource) ? mNextAssertion->mNext : mNextAssertion->u.as.mInvNext; // grab an owning reference from the enumerator to the next assertion if (mNextAssertion) mNextAssertion->AddRef(); // ...and release the reference from the enumerator to the old one. as->Release(); if (foundIt) { *aResult = true; return NS_OK; } } *aResult = false; return NS_OK; } NS_IMETHODIMP InMemoryAssertionEnumeratorImpl::GetNext(nsISupports** aResult) { nsresult rv; bool hasMore; rv = HasMoreElements(&hasMore); if (NS_FAILED(rv)) return rv; if (! hasMore) return NS_ERROR_UNEXPECTED; // Don't AddRef: we "transfer" ownership to the caller *aResult = mValue; mValue = nullptr; return NS_OK; } //////////////////////////////////////////////////////////////////////// // /** * This class is a little bit bizarre in that it implements both the * nsIRDFArcsOutCursor and nsIRDFArcsInCursor interfaces. * Because the structure of the in-memory graph is pretty flexible, it's * fairly easy to parameterize this class. The only funky thing to watch * out for is the multiple inheritance clashes. */ class InMemoryArcsEnumeratorImpl : public nsISimpleEnumerator { private: InMemoryDataSource* mDataSource; nsIRDFResource* mSource; nsIRDFNode* mTarget; nsAutoTArray, 8> mAlreadyReturned; nsIRDFResource* mCurrent; Assertion* mAssertion; nsCOMPtr mHashArcs; virtual ~InMemoryArcsEnumeratorImpl(); public: InMemoryArcsEnumeratorImpl(InMemoryDataSource* aDataSource, nsIRDFResource* aSource, nsIRDFNode* aTarget); // nsISupports interface NS_DECL_ISUPPORTS // nsISimpleEnumerator interface NS_DECL_NSISIMPLEENUMERATOR }; InMemoryArcsEnumeratorImpl::InMemoryArcsEnumeratorImpl(InMemoryDataSource* aDataSource, nsIRDFResource* aSource, nsIRDFNode* aTarget) : mDataSource(aDataSource), mSource(aSource), mTarget(aTarget), mCurrent(nullptr) { NS_ADDREF(mDataSource); NS_IF_ADDREF(mSource); NS_IF_ADDREF(mTarget); if (mSource) { // cast okay because it's a closed system mAssertion = mDataSource->GetForwardArcs(mSource); if (mAssertion && mAssertion->mHashEntry) { // its our magical HASH_ENTRY forward hash for assertions nsresult rv = NS_NewISupportsArray(getter_AddRefs(mHashArcs)); if (NS_SUCCEEDED(rv)) { nsISupportsArray* resources = mHashArcs.get(); for (auto i = mAssertion->u.hash.mPropertyHash->Iter(); !i.Done(); i.Next()) { auto entry = static_cast(i.Get()); resources->AppendElement(entry->mNode); } } mAssertion = nullptr; } } else { mAssertion = mDataSource->GetReverseArcs(mTarget); } } InMemoryArcsEnumeratorImpl::~InMemoryArcsEnumeratorImpl() { #ifdef DEBUG_REFS --gInstanceCount; fprintf(stdout, "%d - RDF: InMemoryArcsEnumeratorImpl\n", gInstanceCount); #endif NS_RELEASE(mDataSource); NS_IF_RELEASE(mSource); NS_IF_RELEASE(mTarget); NS_IF_RELEASE(mCurrent); } NS_IMPL_ADDREF(InMemoryArcsEnumeratorImpl) NS_IMPL_RELEASE(InMemoryArcsEnumeratorImpl) NS_IMPL_QUERY_INTERFACE(InMemoryArcsEnumeratorImpl, nsISimpleEnumerator) NS_IMETHODIMP InMemoryArcsEnumeratorImpl::HasMoreElements(bool* aResult) { NS_PRECONDITION(aResult != nullptr, "null ptr"); if (! aResult) return NS_ERROR_NULL_POINTER; if (mCurrent) { *aResult = true; return NS_OK; } if (mHashArcs) { uint32_t itemCount; nsresult rv; if (NS_FAILED(rv = mHashArcs->Count(&itemCount))) return(rv); if (itemCount > 0) { --itemCount; nsCOMPtr tmp = do_QueryElementAt(mHashArcs, itemCount); tmp.forget(&mCurrent); mHashArcs->RemoveElementAt(itemCount); *aResult = true; return NS_OK; } } else while (mAssertion) { nsIRDFResource* next = mAssertion->u.as.mProperty; // "next" is the property arc we are tentatively going to return // in a subsequent GetNext() call. It is important to do two // things, however, before that can happen: // 1) Make sure it's not an arc we've already returned. // 2) Make sure that |mAssertion| is not left pointing to // another assertion that has the same property as this one. // The first is a practical concern; the second a defense against // an obscure crash and other erratic behavior. To ensure the // second condition, skip down the chain until we find the next // assertion with a property that doesn't match the current one. // (All these assertions would be skipped via mAlreadyReturned // checks anyways; this is even a bit faster.) do { mAssertion = (mSource ? mAssertion->mNext : mAssertion->u.as.mInvNext); } while (mAssertion && (next == mAssertion->u.as.mProperty)); bool alreadyReturned = false; for (int32_t i = mAlreadyReturned.Length() - 1; i >= 0; --i) { if (mAlreadyReturned[i] == next) { alreadyReturned = true; break; } } if (! alreadyReturned) { mCurrent = next; NS_ADDREF(mCurrent); *aResult = true; return NS_OK; } } *aResult = false; return NS_OK; } NS_IMETHODIMP InMemoryArcsEnumeratorImpl::GetNext(nsISupports** aResult) { nsresult rv; bool hasMore; rv = HasMoreElements(&hasMore); if (NS_FAILED(rv)) return rv; if (! hasMore) return NS_ERROR_UNEXPECTED; // Add this to the set of things we've already returned so that we // can ensure uniqueness mAlreadyReturned.AppendElement(mCurrent); // Don't AddRef: we "transfer" ownership to the caller *aResult = mCurrent; mCurrent = nullptr; return NS_OK; } //////////////////////////////////////////////////////////////////////// // InMemoryDataSource nsresult NS_NewRDFInMemoryDataSource(nsISupports* aOuter, const nsIID& aIID, void** aResult) { NS_PRECONDITION(aResult != nullptr, "null ptr"); if (! aResult) return NS_ERROR_NULL_POINTER; *aResult = nullptr; if (aOuter && !aIID.Equals(NS_GET_IID(nsISupports))) { NS_ERROR("aggregation requires nsISupports"); return NS_ERROR_ILLEGAL_VALUE; } InMemoryDataSource* datasource = new InMemoryDataSource(aOuter); NS_ADDREF(datasource); datasource->fAggregated.AddRef(); nsresult rv = datasource->AggregatedQueryInterface(aIID, aResult); // This'll AddRef() datasource->fAggregated.Release(); NS_RELEASE(datasource); return rv; } InMemoryDataSource::InMemoryDataSource(nsISupports* aOuter) : mForwardArcs(PLDHashTable::StubOps(), sizeof(Entry)) , mReverseArcs(PLDHashTable::StubOps(), sizeof(Entry)) , mNumObservers(0) , mReadCount(0) { NS_INIT_AGGREGATED(aOuter); mPropagateChanges = true; MOZ_COUNT_CTOR(InMemoryDataSource); if (! gLog) gLog = PR_NewLogModule("InMemoryDataSource"); } InMemoryDataSource::~InMemoryDataSource() { #ifdef DEBUG_REFS --gInstanceCount; fprintf(stdout, "%d - RDF: InMemoryDataSource\n", gInstanceCount); #endif if (mForwardArcs.EntryCount() > 0) { // This'll release all of the Assertion objects that are // associated with this data source. We only need to do this // for the forward arcs, because the reverse arcs table // indexes the exact same set of resources. for (auto iter = mForwardArcs.Iter(); !iter.Done(); iter.Next()) { auto entry = static_cast(iter.Get()); Assertion* as = entry->mAssertions; while (as) { Assertion* doomed = as; as = as->mNext; // Unlink, and release the datasource's reference. doomed->mNext = doomed->u.as.mInvNext = nullptr; doomed->Release(); } } } MOZ_LOG(gLog, LogLevel::Debug, ("InMemoryDataSource(%p): destroyed.", this)); MOZ_COUNT_DTOR(InMemoryDataSource); } //////////////////////////////////////////////////////////////////////// NS_IMPL_CYCLE_COLLECTION_CLASS(InMemoryDataSource) NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(InMemoryDataSource) NS_IMPL_CYCLE_COLLECTION_UNLINK(mObservers) NS_IMPL_CYCLE_COLLECTION_UNLINK_END NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_AGGREGATED(InMemoryDataSource) NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mObservers) NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END NS_IMPL_CYCLE_COLLECTING_AGGREGATED(InMemoryDataSource) NS_INTERFACE_MAP_BEGIN_AGGREGATED(InMemoryDataSource) NS_INTERFACE_MAP_ENTRIES_CYCLE_COLLECTION_AGGREGATED(InMemoryDataSource) NS_INTERFACE_MAP_ENTRY(nsIRDFDataSource) NS_INTERFACE_MAP_ENTRY(nsIRDFInMemoryDataSource) NS_INTERFACE_MAP_ENTRY(nsIRDFPropagatableDataSource) NS_INTERFACE_MAP_ENTRY(nsIRDFPurgeableDataSource) NS_INTERFACE_MAP_ENTRY(rdfIDataSource) NS_INTERFACE_MAP_END //////////////////////////////////////////////////////////////////////// void InMemoryDataSource::LogOperation(const char* aOperation, nsIRDFResource* aSource, nsIRDFResource* aProperty, nsIRDFNode* aTarget, bool aTruthValue) { if (! MOZ_LOG_TEST(gLog, LogLevel::Debug)) return; nsXPIDLCString uri; aSource->GetValue(getter_Copies(uri)); PR_LogPrint ("InMemoryDataSource(%p): %s", this, aOperation); PR_LogPrint (" [(%p)%s]--", aSource, (const char*) uri); aProperty->GetValue(getter_Copies(uri)); char tv = (aTruthValue ? '-' : '!'); PR_LogPrint (" --%c[(%p)%s]--", tv, aProperty, (const char*) uri); nsCOMPtr resource; nsCOMPtr literal; if ((resource = do_QueryInterface(aTarget)) != nullptr) { resource->GetValue(getter_Copies(uri)); PR_LogPrint (" -->[(%p)%s]", aTarget, (const char*) uri); } else if ((literal = do_QueryInterface(aTarget)) != nullptr) { nsXPIDLString value; literal->GetValue(getter_Copies(value)); nsAutoString valueStr(value); char* valueCStr = ToNewCString(valueStr); PR_LogPrint (" -->(\"%s\")\n", valueCStr); free(valueCStr); } else { PR_LogPrint (" -->(unknown-type)\n"); } } NS_IMETHODIMP InMemoryDataSource::GetURI(char* *uri) { NS_PRECONDITION(uri != nullptr, "null ptr"); if (! uri) return NS_ERROR_NULL_POINTER; *uri = nullptr; return NS_OK; } NS_IMETHODIMP InMemoryDataSource::GetSource(nsIRDFResource* property, nsIRDFNode* target, bool tv, nsIRDFResource** source) { NS_PRECONDITION(source != nullptr, "null ptr"); if (! source) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(property != nullptr, "null ptr"); if (! property) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(target != nullptr, "null ptr"); if (! target) return NS_ERROR_NULL_POINTER; for (Assertion* as = GetReverseArcs(target); as; as = as->u.as.mInvNext) { if ((property == as->u.as.mProperty) && (tv == as->u.as.mTruthValue)) { *source = as->mSource; NS_ADDREF(*source); return NS_OK; } } *source = nullptr; return NS_RDF_NO_VALUE; } NS_IMETHODIMP InMemoryDataSource::GetTarget(nsIRDFResource* source, nsIRDFResource* property, bool tv, nsIRDFNode** target) { NS_PRECONDITION(source != nullptr, "null ptr"); if (! source) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(property != nullptr, "null ptr"); if (! property) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(target != nullptr, "null ptr"); if (! target) return NS_ERROR_NULL_POINTER; Assertion *as = GetForwardArcs(source); if (as && as->mHashEntry) { PLDHashEntryHdr* hdr = as->u.hash.mPropertyHash->Search(property); Assertion* val = hdr ? static_cast(hdr)->mAssertions : nullptr; while (val) { if (tv == val->u.as.mTruthValue) { *target = val->u.as.mTarget; NS_IF_ADDREF(*target); return NS_OK; } val = val->mNext; } } else for (; as != nullptr; as = as->mNext) { if ((property == as->u.as.mProperty) && (tv == (as->u.as.mTruthValue))) { *target = as->u.as.mTarget; NS_ADDREF(*target); return NS_OK; } } // If we get here, then there was no target with for the specified // property & truth value. *target = nullptr; return NS_RDF_NO_VALUE; } NS_IMETHODIMP InMemoryDataSource::HasAssertion(nsIRDFResource* source, nsIRDFResource* property, nsIRDFNode* target, bool tv, bool* hasAssertion) { if (! source) return NS_ERROR_NULL_POINTER; if (! property) return NS_ERROR_NULL_POINTER; if (! target) return NS_ERROR_NULL_POINTER; Assertion *as = GetForwardArcs(source); if (as && as->mHashEntry) { PLDHashEntryHdr* hdr = as->u.hash.mPropertyHash->Search(property); Assertion* val = hdr ? static_cast(hdr)->mAssertions : nullptr; while (val) { if ((val->u.as.mTarget == target) && (tv == (val->u.as.mTruthValue))) { *hasAssertion = true; return NS_OK; } val = val->mNext; } } else for (; as != nullptr; as = as->mNext) { // check target first as its most unique if (target != as->u.as.mTarget) continue; if (property != as->u.as.mProperty) continue; if (tv != (as->u.as.mTruthValue)) continue; // found it! *hasAssertion = true; return NS_OK; } // If we get here, we couldn't find the assertion *hasAssertion = false; return NS_OK; } NS_IMETHODIMP InMemoryDataSource::GetSources(nsIRDFResource* aProperty, nsIRDFNode* aTarget, bool aTruthValue, nsISimpleEnumerator** aResult) { NS_PRECONDITION(aProperty != nullptr, "null ptr"); if (! aProperty) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(aTarget != nullptr, "null ptr"); if (! aTarget) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(aResult != nullptr, "null ptr"); if (! aResult) return NS_ERROR_NULL_POINTER; InMemoryAssertionEnumeratorImpl* result = new InMemoryAssertionEnumeratorImpl(this, nullptr, aProperty, aTarget, aTruthValue); if (! result) return NS_ERROR_OUT_OF_MEMORY; NS_ADDREF(result); *aResult = result; return NS_OK; } NS_IMETHODIMP InMemoryDataSource::GetTargets(nsIRDFResource* aSource, nsIRDFResource* aProperty, bool aTruthValue, nsISimpleEnumerator** aResult) { NS_PRECONDITION(aSource != nullptr, "null ptr"); if (! aSource) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(aProperty != nullptr, "null ptr"); if (! aProperty) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(aResult != nullptr, "null ptr"); if (! aResult) return NS_ERROR_NULL_POINTER; InMemoryAssertionEnumeratorImpl* result = new InMemoryAssertionEnumeratorImpl(this, aSource, aProperty, nullptr, aTruthValue); if (! result) return NS_ERROR_OUT_OF_MEMORY; NS_ADDREF(result); *aResult = result; return NS_OK; } nsresult InMemoryDataSource::LockedAssert(nsIRDFResource* aSource, nsIRDFResource* aProperty, nsIRDFNode* aTarget, bool aTruthValue) { LogOperation("ASSERT", aSource, aProperty, aTarget, aTruthValue); Assertion* next = GetForwardArcs(aSource); Assertion* prev = next; Assertion* as = nullptr; bool haveHash = (next) ? next->mHashEntry : false; if (haveHash) { PLDHashEntryHdr* hdr = next->u.hash.mPropertyHash->Search(aProperty); Assertion* val = hdr ? static_cast(hdr)->mAssertions : nullptr; while (val) { if (val->u.as.mTarget == aTarget) { // Wow, we already had the assertion. Make sure that the // truth values are correct and bail. val->u.as.mTruthValue = aTruthValue; return NS_OK; } val = val->mNext; } } else { while (next) { // check target first as its most unique if (aTarget == next->u.as.mTarget) { if (aProperty == next->u.as.mProperty) { // Wow, we already had the assertion. Make sure that the // truth values are correct and bail. next->u.as.mTruthValue = aTruthValue; return NS_OK; } } prev = next; next = next->mNext; } } as = new Assertion(aSource, aProperty, aTarget, aTruthValue); if (! as) return NS_ERROR_OUT_OF_MEMORY; // Add the datasource's owning reference. as->AddRef(); if (haveHash) { PLDHashEntryHdr* hdr = next->u.hash.mPropertyHash->Search(aProperty); Assertion *asRef = hdr ? static_cast(hdr)->mAssertions : nullptr; if (asRef) { as->mNext = asRef->mNext; asRef->mNext = as; } else { hdr = next->u.hash.mPropertyHash->Add(aProperty, mozilla::fallible); if (hdr) { Entry* entry = static_cast(hdr); entry->mNode = aProperty; entry->mAssertions = as; } } } else { // Link it in to the "forward arcs" table if (!prev) { SetForwardArcs(aSource, as); } else { prev->mNext = as; } } // Link it in to the "reverse arcs" table next = GetReverseArcs(aTarget); as->u.as.mInvNext = next; next = as; SetReverseArcs(aTarget, next); return NS_OK; } NS_IMETHODIMP InMemoryDataSource::Assert(nsIRDFResource* aSource, nsIRDFResource* aProperty, nsIRDFNode* aTarget, bool aTruthValue) { NS_PRECONDITION(aSource != nullptr, "null ptr"); if (! aSource) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(aProperty != nullptr, "null ptr"); if (! aProperty) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(aTarget != nullptr, "null ptr"); if (! aTarget) return NS_ERROR_NULL_POINTER; if (mReadCount) { NS_WARNING("Writing to InMemoryDataSource during read\n"); return NS_RDF_ASSERTION_REJECTED; } nsresult rv; rv = LockedAssert(aSource, aProperty, aTarget, aTruthValue); if (NS_FAILED(rv)) return rv; // notify observers for (int32_t i = (int32_t)mNumObservers - 1; mPropagateChanges && i >= 0; --i) { nsIRDFObserver* obs = mObservers[i]; // XXX this should never happen, but it does, and we can't figure out why. NS_ASSERTION(obs, "observer array corrupted!"); if (! obs) continue; obs->OnAssert(this, aSource, aProperty, aTarget); // XXX ignore return value? } return NS_RDF_ASSERTION_ACCEPTED; } nsresult InMemoryDataSource::LockedUnassert(nsIRDFResource* aSource, nsIRDFResource* aProperty, nsIRDFNode* aTarget) { LogOperation("UNASSERT", aSource, aProperty, aTarget); Assertion* next = GetForwardArcs(aSource); Assertion* prev = next; Assertion* root = next; Assertion* as = nullptr; bool haveHash = (next) ? next->mHashEntry : false; if (haveHash) { PLDHashEntryHdr* hdr = next->u.hash.mPropertyHash->Search(aProperty); prev = next = hdr ? static_cast(hdr)->mAssertions : nullptr; bool first = true; while (next) { if (aTarget == next->u.as.mTarget) { break; } first = false; prev = next; next = next->mNext; } // We don't even have the assertion, so just bail. if (!next) return NS_OK; as = next; if (first) { root->u.hash.mPropertyHash->RawRemove(hdr); if (next && next->mNext) { PLDHashEntryHdr* hdr = root->u.hash.mPropertyHash->Add(aProperty, mozilla::fallible); if (hdr) { Entry* entry = static_cast(hdr); entry->mNode = aProperty; entry->mAssertions = next->mNext; } } else { // If this second-level hash empties out, clean it up. if (!root->u.hash.mPropertyHash->EntryCount()) { root->Release(); SetForwardArcs(aSource, nullptr); } } } else { prev->mNext = next->mNext; } } else { while (next) { // check target first as its most unique if (aTarget == next->u.as.mTarget) { if (aProperty == next->u.as.mProperty) { if (prev == next) { SetForwardArcs(aSource, next->mNext); } else { prev->mNext = next->mNext; } as = next; break; } } prev = next; next = next->mNext; } } // We don't even have the assertion, so just bail. if (!as) return NS_OK; #ifdef DEBUG bool foundReverseArc = false; #endif next = prev = GetReverseArcs(aTarget); while (next) { if (next == as) { if (prev == next) { SetReverseArcs(aTarget, next->u.as.mInvNext); } else { prev->u.as.mInvNext = next->u.as.mInvNext; } #ifdef DEBUG foundReverseArc = true; #endif break; } prev = next; next = next->u.as.mInvNext; } #ifdef DEBUG NS_ASSERTION(foundReverseArc, "in-memory db corrupted: unable to find reverse arc"); #endif // Unlink, and release the datasource's reference as->mNext = as->u.as.mInvNext = nullptr; as->Release(); return NS_OK; } NS_IMETHODIMP InMemoryDataSource::Unassert(nsIRDFResource* aSource, nsIRDFResource* aProperty, nsIRDFNode* aTarget) { NS_PRECONDITION(aSource != nullptr, "null ptr"); if (! aSource) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(aProperty != nullptr, "null ptr"); if (! aProperty) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(aTarget != nullptr, "null ptr"); if (! aTarget) return NS_ERROR_NULL_POINTER; if (mReadCount) { NS_WARNING("Writing to InMemoryDataSource during read\n"); return NS_RDF_ASSERTION_REJECTED; } nsresult rv; rv = LockedUnassert(aSource, aProperty, aTarget); if (NS_FAILED(rv)) return rv; // Notify the world for (int32_t i = int32_t(mNumObservers) - 1; mPropagateChanges && i >= 0; --i) { nsIRDFObserver* obs = mObservers[i]; // XXX this should never happen, but it does, and we can't figure out why. NS_ASSERTION(obs, "observer array corrupted!"); if (! obs) continue; obs->OnUnassert(this, aSource, aProperty, aTarget); // XXX ignore return value? } return NS_RDF_ASSERTION_ACCEPTED; } NS_IMETHODIMP InMemoryDataSource::Change(nsIRDFResource* aSource, nsIRDFResource* aProperty, nsIRDFNode* aOldTarget, nsIRDFNode* aNewTarget) { NS_PRECONDITION(aSource != nullptr, "null ptr"); if (! aSource) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(aProperty != nullptr, "null ptr"); if (! aProperty) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(aOldTarget != nullptr, "null ptr"); if (! aOldTarget) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(aNewTarget != nullptr, "null ptr"); if (! aNewTarget) return NS_ERROR_NULL_POINTER; if (mReadCount) { NS_WARNING("Writing to InMemoryDataSource during read\n"); return NS_RDF_ASSERTION_REJECTED; } nsresult rv; // XXX We can implement LockedChange() if we decide that this // is a performance bottleneck. rv = LockedUnassert(aSource, aProperty, aOldTarget); if (NS_FAILED(rv)) return rv; rv = LockedAssert(aSource, aProperty, aNewTarget, true); if (NS_FAILED(rv)) return rv; // Notify the world for (int32_t i = int32_t(mNumObservers) - 1; mPropagateChanges && i >= 0; --i) { nsIRDFObserver* obs = mObservers[i]; // XXX this should never happen, but it does, and we can't figure out why. NS_ASSERTION(obs, "observer array corrupted!"); if (! obs) continue; obs->OnChange(this, aSource, aProperty, aOldTarget, aNewTarget); // XXX ignore return value? } return NS_RDF_ASSERTION_ACCEPTED; } NS_IMETHODIMP InMemoryDataSource::Move(nsIRDFResource* aOldSource, nsIRDFResource* aNewSource, nsIRDFResource* aProperty, nsIRDFNode* aTarget) { NS_PRECONDITION(aOldSource != nullptr, "null ptr"); if (! aOldSource) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(aNewSource != nullptr, "null ptr"); if (! aNewSource) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(aProperty != nullptr, "null ptr"); if (! aProperty) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(aTarget != nullptr, "null ptr"); if (! aTarget) return NS_ERROR_NULL_POINTER; if (mReadCount) { NS_WARNING("Writing to InMemoryDataSource during read\n"); return NS_RDF_ASSERTION_REJECTED; } nsresult rv; // XXX We can implement LockedMove() if we decide that this // is a performance bottleneck. rv = LockedUnassert(aOldSource, aProperty, aTarget); if (NS_FAILED(rv)) return rv; rv = LockedAssert(aNewSource, aProperty, aTarget, true); if (NS_FAILED(rv)) return rv; // Notify the world for (int32_t i = int32_t(mNumObservers) - 1; mPropagateChanges && i >= 0; --i) { nsIRDFObserver* obs = mObservers[i]; // XXX this should never happen, but it does, and we can't figure out why. NS_ASSERTION(obs, "observer array corrupted!"); if (! obs) continue; obs->OnMove(this, aOldSource, aNewSource, aProperty, aTarget); // XXX ignore return value? } return NS_RDF_ASSERTION_ACCEPTED; } NS_IMETHODIMP InMemoryDataSource::AddObserver(nsIRDFObserver* aObserver) { NS_PRECONDITION(aObserver != nullptr, "null ptr"); if (! aObserver) return NS_ERROR_NULL_POINTER; mObservers.AppendObject(aObserver); mNumObservers = mObservers.Count(); return NS_OK; } NS_IMETHODIMP InMemoryDataSource::RemoveObserver(nsIRDFObserver* aObserver) { NS_PRECONDITION(aObserver != nullptr, "null ptr"); if (! aObserver) return NS_ERROR_NULL_POINTER; mObservers.RemoveObject(aObserver); // note: use Count() instead of just decrementing // in case aObserver wasn't in list, for example mNumObservers = mObservers.Count(); return NS_OK; } NS_IMETHODIMP InMemoryDataSource::HasArcIn(nsIRDFNode *aNode, nsIRDFResource *aArc, bool *result) { Assertion* ass = GetReverseArcs(aNode); while (ass) { nsIRDFResource* elbow = ass->u.as.mProperty; if (elbow == aArc) { *result = true; return NS_OK; } ass = ass->u.as.mInvNext; } *result = false; return NS_OK; } NS_IMETHODIMP InMemoryDataSource::HasArcOut(nsIRDFResource *aSource, nsIRDFResource *aArc, bool *result) { Assertion* ass = GetForwardArcs(aSource); if (ass && ass->mHashEntry) { PLDHashEntryHdr* hdr = ass->u.hash.mPropertyHash->Search(aArc); Assertion* val = hdr ? static_cast(hdr)->mAssertions : nullptr; if (val) { *result = true; return NS_OK; } ass = ass->mNext; } while (ass) { nsIRDFResource* elbow = ass->u.as.mProperty; if (elbow == aArc) { *result = true; return NS_OK; } ass = ass->mNext; } *result = false; return NS_OK; } NS_IMETHODIMP InMemoryDataSource::ArcLabelsIn(nsIRDFNode* aTarget, nsISimpleEnumerator** aResult) { NS_PRECONDITION(aTarget != nullptr, "null ptr"); if (! aTarget) return NS_ERROR_NULL_POINTER; InMemoryArcsEnumeratorImpl* result = new InMemoryArcsEnumeratorImpl(this, nullptr, aTarget); if (! result) return NS_ERROR_OUT_OF_MEMORY; NS_ADDREF(result); *aResult = result; return NS_OK; } NS_IMETHODIMP InMemoryDataSource::ArcLabelsOut(nsIRDFResource* aSource, nsISimpleEnumerator** aResult) { NS_PRECONDITION(aSource != nullptr, "null ptr"); if (! aSource) return NS_ERROR_NULL_POINTER; InMemoryArcsEnumeratorImpl* result = new InMemoryArcsEnumeratorImpl(this, aSource, nullptr); if (! result) return NS_ERROR_OUT_OF_MEMORY; NS_ADDREF(result); *aResult = result; return NS_OK; } NS_IMETHODIMP InMemoryDataSource::GetAllResources(nsISimpleEnumerator** aResult) { nsCOMArray nodes; nodes.SetCapacity(mForwardArcs.EntryCount()); // Get all of our entries into an nsCOMArray for (auto iter = mForwardArcs.Iter(); !iter.Done(); iter.Next()) { auto entry = static_cast(iter.Get()); nodes.AppendObject(entry->mNode); } return NS_NewArrayEnumerator(aResult, nodes); } NS_IMETHODIMP InMemoryDataSource::GetAllCmds(nsIRDFResource* source, nsISimpleEnumerator/**/** commands) { return(NS_NewEmptyEnumerator(commands)); } NS_IMETHODIMP InMemoryDataSource::IsCommandEnabled(nsISupportsArray/**/* aSources, nsIRDFResource* aCommand, nsISupportsArray/**/* aArguments, bool* aResult) { *aResult = false; return NS_OK; } NS_IMETHODIMP InMemoryDataSource::DoCommand(nsISupportsArray/**/* aSources, nsIRDFResource* aCommand, nsISupportsArray/**/* aArguments) { return NS_OK; } NS_IMETHODIMP InMemoryDataSource::BeginUpdateBatch() { for (int32_t i = int32_t(mNumObservers) - 1; mPropagateChanges && i >= 0; --i) { nsIRDFObserver* obs = mObservers[i]; obs->OnBeginUpdateBatch(this); } return NS_OK; } NS_IMETHODIMP InMemoryDataSource::EndUpdateBatch() { for (int32_t i = int32_t(mNumObservers) - 1; mPropagateChanges && i >= 0; --i) { nsIRDFObserver* obs = mObservers[i]; obs->OnEndUpdateBatch(this); } return NS_OK; } //////////////////////////////////////////////////////////////////////// // nsIRDFInMemoryDataSource methods NS_IMETHODIMP InMemoryDataSource::EnsureFastContainment(nsIRDFResource* aSource) { Assertion *as = GetForwardArcs(aSource); bool haveHash = (as) ? as->mHashEntry : false; // if its already a hash, then nothing to do if (haveHash) return(NS_OK); // convert aSource in forward hash into a hash Assertion *hashAssertion = new Assertion(aSource); NS_ASSERTION(hashAssertion, "unable to create Assertion"); if (!hashAssertion) return(NS_ERROR_OUT_OF_MEMORY); // Add the datasource's owning reference. hashAssertion->AddRef(); Assertion *first = GetForwardArcs(aSource); SetForwardArcs(aSource, hashAssertion); // mutate references of existing forward assertions into this hash PLDHashTable *table = hashAssertion->u.hash.mPropertyHash; Assertion *nextRef; while(first) { nextRef = first->mNext; nsIRDFResource *prop = first->u.as.mProperty; PLDHashEntryHdr* hdr = table->Search(prop); Assertion* val = hdr ? static_cast(hdr)->mAssertions : nullptr; if (val) { first->mNext = val->mNext; val->mNext = first; } else { PLDHashEntryHdr* hdr = table->Add(prop, mozilla::fallible); if (hdr) { Entry* entry = static_cast(hdr); entry->mNode = prop; entry->mAssertions = first; first->mNext = nullptr; } } first = nextRef; } return(NS_OK); } //////////////////////////////////////////////////////////////////////// // nsIRDFPropagatableDataSource methods NS_IMETHODIMP InMemoryDataSource::GetPropagateChanges(bool* aPropagateChanges) { *aPropagateChanges = mPropagateChanges; return NS_OK; } NS_IMETHODIMP InMemoryDataSource::SetPropagateChanges(bool aPropagateChanges) { mPropagateChanges = aPropagateChanges; return NS_OK; } //////////////////////////////////////////////////////////////////////// // nsIRDFPurgeableDataSource methods NS_IMETHODIMP InMemoryDataSource::Mark(nsIRDFResource* aSource, nsIRDFResource* aProperty, nsIRDFNode* aTarget, bool aTruthValue, bool* aDidMark) { NS_PRECONDITION(aSource != nullptr, "null ptr"); if (! aSource) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(aProperty != nullptr, "null ptr"); if (! aProperty) return NS_ERROR_NULL_POINTER; NS_PRECONDITION(aTarget != nullptr, "null ptr"); if (! aTarget) return NS_ERROR_NULL_POINTER; Assertion *as = GetForwardArcs(aSource); if (as && as->mHashEntry) { PLDHashEntryHdr* hdr = as->u.hash.mPropertyHash->Search(aProperty); Assertion* val = hdr ? static_cast(hdr)->mAssertions : nullptr; while (val) { if ((val->u.as.mTarget == aTarget) && (aTruthValue == (val->u.as.mTruthValue))) { // found it! so mark it. as->Mark(); *aDidMark = true; LogOperation("MARK", aSource, aProperty, aTarget, aTruthValue); return NS_OK; } val = val->mNext; } } else for (; as != nullptr; as = as->mNext) { // check target first as its most unique if (aTarget != as->u.as.mTarget) continue; if (aProperty != as->u.as.mProperty) continue; if (aTruthValue != (as->u.as.mTruthValue)) continue; // found it! so mark it. as->Mark(); *aDidMark = true; LogOperation("MARK", aSource, aProperty, aTarget, aTruthValue); return NS_OK; } // If we get here, we couldn't find the assertion *aDidMark = false; return NS_OK; } NS_IMETHODIMP InMemoryDataSource::Sweep() { SweepInfo info = { nullptr, &mReverseArcs }; // Remove all the assertions, but don't notify anyone. SweepForwardArcsEntries(&mForwardArcs, &info); // Now do the notification. Assertion* as = info.mUnassertList; while (as) { LogOperation("SWEEP", as->mSource, as->u.as.mProperty, as->u.as.mTarget, as->u.as.mTruthValue); if (!(as->mHashEntry)) { for (int32_t i = int32_t(mNumObservers) - 1; mPropagateChanges && i >= 0; --i) { nsIRDFObserver* obs = mObservers[i]; // XXXbz other loops over mObservers null-check |obs| here! obs->OnUnassert(this, as->mSource, as->u.as.mProperty, as->u.as.mTarget); // XXX ignore return value? } } Assertion* doomed = as; as = as->mNext; // Unlink, and release the datasource's reference doomed->mNext = doomed->u.as.mInvNext = nullptr; doomed->Release(); } return NS_OK; } void InMemoryDataSource::SweepForwardArcsEntries(PLDHashTable* aTable, SweepInfo* aInfo) { for (auto iter = aTable->Iter(); !iter.Done(); iter.Next()) { auto entry = static_cast(iter.Get()); Assertion* as = entry->mAssertions; if (as && (as->mHashEntry)) { // Stuff in sub-hashes must be swept recursively (max depth: 1) SweepForwardArcsEntries(as->u.hash.mPropertyHash, aInfo); // If the sub-hash is now empty, clean it up. if (!as->u.hash.mPropertyHash->EntryCount()) { as->Release(); iter.Remove(); } continue; } Assertion* prev = nullptr; while (as) { if (as->IsMarked()) { prev = as; as->Unmark(); as = as->mNext; } else { // remove from the list of assertions in the datasource Assertion* next = as->mNext; if (prev) { prev->mNext = next; } else { // it's the first one. update the hashtable entry. entry->mAssertions = next; } // remove from the reverse arcs PLDHashEntryHdr* hdr = aInfo->mReverseArcs->Search(as->u.as.mTarget); NS_ASSERTION(hdr, "no assertion in reverse arcs"); Entry* rentry = static_cast(hdr); Assertion* ras = rentry->mAssertions; Assertion* rprev = nullptr; while (ras) { if (ras == as) { if (rprev) { rprev->u.as.mInvNext = ras->u.as.mInvNext; } else { // it's the first one. update the hashtable entry. rentry->mAssertions = ras->u.as.mInvNext; } as->u.as.mInvNext = nullptr; // for my sanity. break; } rprev = ras; ras = ras->u.as.mInvNext; } // Wow, it was the _only_ one. Unhash it. if (! rentry->mAssertions) { aInfo->mReverseArcs->RawRemove(hdr); } // add to the list of assertions to unassert as->mNext = aInfo->mUnassertList; aInfo->mUnassertList = as; // Advance to the next assertion as = next; } } // if no more assertions exist for this resource, then unhash it. if (! entry->mAssertions) { iter.Remove(); } } } //////////////////////////////////////////////////////////////////////// // rdfIDataSource methods NS_IMETHODIMP InMemoryDataSource::VisitAllSubjects(rdfITripleVisitor *aVisitor) { // Lock datasource against writes ++mReadCount; // Enumerate all of our entries into an nsISupportsArray. nsresult rv = NS_OK; for (auto iter = mForwardArcs.Iter(); !iter.Done(); iter.Next()) { auto entry = static_cast(iter.Get()); nsresult rv2; nsCOMPtr subject = do_QueryInterface(entry->mNode, &rv2); if (NS_FAILED(rv2)) { NS_WARNING("QI to nsIRDFNode failed"); continue; } rv = aVisitor->Visit(subject, nullptr, nullptr, true); if (NS_FAILED(rv) || rv == NS_RDF_STOP_VISIT) { break; } } // Unlock datasource --mReadCount; return rv; } NS_IMETHODIMP InMemoryDataSource::VisitAllTriples(rdfITripleVisitor *aVisitor) { // Lock datasource against writes ++mReadCount; // Enumerate all of our entries into an nsISupportsArray. nsresult rv = NS_OK; for (auto iter = mForwardArcs.Iter(); !iter.Done(); iter.Next()) { auto entry = static_cast(iter.Get()); nsresult rv2; nsCOMPtr subject = do_QueryInterface(entry->mNode, &rv2); if (NS_FAILED(rv2)) { NS_WARNING("QI to nsIRDFNode failed"); } else if (entry->mAssertions->mHashEntry) { for (auto iter = entry->mAssertions->u.hash.mPropertyHash->Iter(); !iter.Done(); iter.Next()) { auto entry = static_cast(iter.Get()); Assertion* assertion = entry->mAssertions; while (assertion) { NS_ASSERTION(!assertion->mHashEntry, "shouldn't have to hashes"); rv = aVisitor->Visit(subject, assertion->u.as.mProperty, assertion->u.as.mTarget, assertion->u.as.mTruthValue); if (NS_FAILED(rv)) { goto end; } if (rv == NS_RDF_STOP_VISIT) { goto inner_end; } assertion = assertion->mNext; } } } else { Assertion* assertion = entry->mAssertions; while (assertion) { NS_ASSERTION(!assertion->mHashEntry, "shouldn't have to hashes"); rv = aVisitor->Visit(subject, assertion->u.as.mProperty, assertion->u.as.mTarget, assertion->u.as.mTruthValue); if (NS_FAILED(rv) || rv == NS_RDF_STOP_VISIT) { goto end; } assertion = assertion->mNext; } } inner_end: (void) 0; } end: // Unlock datasource --mReadCount; return rv; } ////////////////////////////////////////////////////////////////////////