The Tor Browser: comparison content/xul/templates/src/nsRDFBinding.h

--1:000000000000
+:aaa9dcdaa45d
+/* -*- 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/. */
+#ifndef nsRDFBinding_h__
+#define nsRDFBinding_h__
+#include "nsAutoPtr.h"
+#include "nsIAtom.h"
+#include "nsIRDFResource.h"
+#include "nsISupportsImpl.h"
+class nsXULTemplateResultRDF;
+class nsBindingValues;
+/*
+* Classes related to storing bindings for RDF handling.
+*/
+/*
+* a  <binding> descriptors
+*/
+class RDFBinding {
+public:
+nsCOMPtr<nsIAtom>        mSubjectVariable;
+nsCOMPtr<nsIRDFResource> mPredicate;
+nsCOMPtr<nsIAtom>        mTargetVariable;
+// indicates whether a binding is dependant on the result from a
+// previous binding
+bool                     mHasDependency;
+RDFBinding*              mNext;
+private:
+friend class RDFBindingSet;
+RDFBinding(nsIAtom* aSubjectVariable,
+nsIRDFResource* aPredicate,
+nsIAtom* aTargetVariable)
+: mSubjectVariable(aSubjectVariable),
+mPredicate(aPredicate),
+mTargetVariable(aTargetVariable),
+mHasDependency(false),
+mNext(nullptr)
+{
+MOZ_COUNT_CTOR(RDFBinding);
+}
+~RDFBinding()
+{
+MOZ_COUNT_DTOR(RDFBinding);
+}
+};
+/*
+* a collection of <binding> descriptors. This object is refcounted by
+* nsBindingValues objects and the query processor.
+*/
+class RDFBindingSet MOZ_FINAL
+{
+private:
+// Private destructor, to discourage deletion outside of Release():
+~RDFBindingSet();
+// the number of bindings
+int32_t mCount;
+// pointer to the first binding in a linked list
+RDFBinding* mFirst;
+public:
+RDFBindingSet()
+: mCount(0),
+mFirst(nullptr)
+{
+MOZ_COUNT_CTOR(RDFBindingSet);
+}
+NS_INLINE_DECL_REFCOUNTING(RDFBindingSet)
+int32_t Count() const { return mCount; }
+/*
+* Add a binding (aRef -> aPredicate -> aVar) to the set
+*/
+nsresult
+AddBinding(nsIAtom* aVar, nsIAtom* aRef, nsIRDFResource* aPredicate);
+/*
+* Return true if the binding set contains a binding which would cause
+* the result to need resynchronizing for an RDF triple. The member
+* variable may be supplied as an optimization since bindings most
+* commonly use the member variable as the subject. If aMemberVariable
+* is set, aSubject must be the value of the member variable for the
+* result. The supplied binding values aBindingValues must be values
+* using this binding set (that is aBindingValues->GetBindingSet() == this)
+*
+* @param aSubject subject of the RDF triple
+* @param aPredicate predicate of the RDF triple
+* @param aTarget target of the RDF triple
+* @param aMemberVariable member variable for the query for the binding
+* @param aResult result to synchronize
+* @param aBindingValues the values for the bindings for the result
+*/
+bool
+SyncAssignments(nsIRDFResource* aSubject,
+nsIRDFResource* aPredicate,
+nsIRDFNode* aTarget,
+nsIAtom* aMemberVariable,
+nsXULTemplateResultRDF* aResult,
+nsBindingValues& aBindingValues);
+/*
+* The query processor maintains a map of subjects to an array of results.
+* This is used such that when a new assertion is added to the RDF graph,
+* the results associated with the subject of that triple may be checked
+* to see if their bindings have changed. The AddDependencies method adds
+* these subject dependencies to the map.
+*/
+void
+AddDependencies(nsIRDFResource* aSubject,
+nsXULTemplateResultRDF* aResult);
+/*
+* Remove the results from the dependencies map when results are deleted.
+*/
+void
+RemoveDependencies(nsIRDFResource* aSubject,
+nsXULTemplateResultRDF* aResult);
+/*
+* The nsBindingValues classes stores an array of values, one for each
+* target symbol that could be set by the bindings in the set.
+* LookupTargetIndex determines the index into the array for a given
+* target symbol.
+*/
+int32_t
+LookupTargetIndex(nsIAtom* aTargetVariable, RDFBinding** aBinding);
+};
+/*
+* A set of values of bindings. This object is used once per result.
+* This stores a reference to the binding set and an array of node values.
+* Since the binding set is used once per query and the values are
+* used once per result, we reduce size by only storing the value array's
+* length in the binding set. This is possible since the array is always
+* a fixed length for a particular binding set.
+*
+* XXX ndeakin We may want to revisit this later since it makes the code
+*             more complicated.
+*/
+class nsBindingValues
+{
+protected:
+// the binding set
+nsRefPtr<RDFBindingSet> mBindings;
+/*
+* A set of values for variable bindings. To look up a binding value,
+* scan through the binding set in mBindings for the right target atom.
+* Its index will correspond to the index in this array. The size of this
+* array is determined by the RDFBindingSet's Count().
+*/
+nsCOMPtr<nsIRDFNode>* mValues;
+public:
+nsBindingValues()
+: mBindings(nullptr),
+mValues(nullptr)
+{
+MOZ_COUNT_CTOR(nsBindingValues);
+}
+~nsBindingValues();
+/**
+* Clear the binding set, to be called when the nsBindingValues is deleted
+* or a new binding set is being set.
+*/
+void ClearBindingSet();
+RDFBindingSet* GetBindingSet() { return mBindings; }
+/**
+* Set the binding set to use. This needs to be called once a rule matches
+* since it is then known which bindings will apply.
+*/
+nsresult SetBindingSet(RDFBindingSet* aBindings);
+nsCOMPtr<nsIRDFNode>* ValuesArray() { return mValues; }
+/*
+* Retrieve the assignment for a particular variable
+*/
+void
+GetAssignmentFor(nsXULTemplateResultRDF* aResult,
+nsIAtom* aVar,
+nsIRDFNode** aValue);
+/*
+* Remove depenedencies the bindings have on particular resources
+*/
+void
+RemoveDependencies(nsIRDFResource* aSubject,
+nsXULTemplateResultRDF* aResult);
+};
+#endif // nsRDFBinding_h__

The Tor Browser / file comparison

comparison: content/xul/templates/src/nsRDFBinding.h

content/xul/templates/src/nsRDFBinding.h