import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

dom/xul/templates/nsRDFBinding.cpp

@@ -0,0 +1,265 @@
+/* -*- 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/. */
+
+#include "nsXULTemplateQueryProcessorRDF.h"
+#include "nsXULTemplateResultRDF.h"
+#include "nsRDFBinding.h"
+
+#ifdef DEBUG
+#include "nsXULContentUtils.h"
+#endif
+
+RDFBindingSet::~RDFBindingSet()
+{
+    while (mFirst) {
+        RDFBinding* doomed = mFirst;
+        mFirst = mFirst->mNext;
+        delete doomed;
+    }
+
+    MOZ_COUNT_DTOR(RDFBindingSet);
+}
+
+nsresult
+RDFBindingSet::AddBinding(nsIAtom* aVar, nsIAtom* aRef, nsIRDFResource* aPredicate)
+{
+    RDFBinding* newbinding = new RDFBinding(aRef, aPredicate, aVar);
+    if (mFirst) {
+        RDFBinding* binding = mFirst;
+
+        while (binding) { 
+            // the binding is dependant on the calculation of a previous binding
+            if (binding->mSubjectVariable == aVar)
+                newbinding->mHasDependency = true;
+
+            // if the target variable is already used in a binding, ignore it
+            // since it won't be useful for anything
+            if (binding->mTargetVariable == aVar) {
+                delete newbinding;
+                return NS_OK;
+            }
+
+            // add the binding at the end of the list
+            if (! binding->mNext) {
+                binding->mNext = newbinding;
+                break;
+            }
+
+            binding = binding->mNext;
+        }
+    }
+    else {
+        mFirst = newbinding;
+    }
+
+    mCount++;
+
+    return NS_OK;
+}
+
+bool
+RDFBindingSet::SyncAssignments(nsIRDFResource* aSubject,
+                               nsIRDFResource* aPredicate,
+                               nsIRDFNode* aTarget,
+                               nsIAtom* aMemberVariable,
+                               nsXULTemplateResultRDF* aResult,
+                               nsBindingValues& aBindingValues)
+{
+    NS_ASSERTION(aBindingValues.GetBindingSet() == this,
+                 "nsBindingValues not for this RDFBindingSet");
+    NS_PRECONDITION(aResult, "Must have result");
+
+    bool needSync = false;
+    nsCOMPtr<nsIRDFNode>* valuesArray = aBindingValues.ValuesArray();
+    if (!valuesArray)
+        return false;
+
+    RDFBinding* binding = mFirst;
+    int32_t count = 0;
+
+    // QI for proper comparisons just to be safe
+    nsCOMPtr<nsIRDFNode> subjectnode = do_QueryInterface(aSubject);
+
+    // iterate through the bindings looking for ones that would match the RDF
+    // nodes that were involved in a change
+    nsCOMPtr<nsIRDFNode> value;
+    while (binding) {
+        if (aPredicate == binding->mPredicate) {
+            // if the source of the binding is the member variable, optimize
+            if (binding->mSubjectVariable == aMemberVariable) {
+                valuesArray[count] = aTarget;
+                needSync = true;
+            }
+            else {
+                aResult->GetAssignment(binding->mSubjectVariable, getter_AddRefs(value));
+                if (value == subjectnode) {
+                    valuesArray[count] = aTarget;
+                    needSync = true;
+                }
+            }
+        }
+
+        binding = binding->mNext;
+        count++;
+    }
+
+    return needSync;
+}
+
+void
+RDFBindingSet::AddDependencies(nsIRDFResource* aSubject,
+                               nsXULTemplateResultRDF* aResult)
+{
+    NS_PRECONDITION(aResult, "Must have result");
+
+    // iterate through the bindings and add binding dependencies to the
+    // processor
+
+    nsXULTemplateQueryProcessorRDF* processor = aResult->GetProcessor();
+    if (! processor)
+        return;
+
+    nsCOMPtr<nsIRDFNode> value;
+
+    RDFBinding* binding = mFirst;
+    while (binding) {
+        aResult->GetAssignment(binding->mSubjectVariable, getter_AddRefs(value));
+
+        nsCOMPtr<nsIRDFResource> valueres = do_QueryInterface(value);
+        if (valueres)
+            processor->AddBindingDependency(aResult, valueres);
+
+        binding = binding->mNext;
+    }
+}
+
+void
+RDFBindingSet::RemoveDependencies(nsIRDFResource* aSubject,
+                                  nsXULTemplateResultRDF* aResult)
+{
+    NS_PRECONDITION(aResult, "Must have result");
+
+    // iterate through the bindings and remove binding dependencies from the
+    // processor
+
+    nsXULTemplateQueryProcessorRDF* processor = aResult->GetProcessor();
+    if (! processor)
+        return;
+
+    nsCOMPtr<nsIRDFNode> value;
+
+    RDFBinding* binding = mFirst;
+    while (binding) {
+        aResult->GetAssignment(binding->mSubjectVariable, getter_AddRefs(value));
+
+        nsCOMPtr<nsIRDFResource> valueres = do_QueryInterface(value);
+        if (valueres)
+            processor->RemoveBindingDependency(aResult, valueres);
+
+        binding = binding->mNext;
+    }
+}
+
+int32_t
+RDFBindingSet::LookupTargetIndex(nsIAtom* aTargetVariable, RDFBinding** aBinding)
+{
+    int32_t idx = 0;
+    RDFBinding* binding = mFirst;
+
+    while (binding) {
+        if (binding->mTargetVariable == aTargetVariable) {
+            *aBinding = binding;
+            return idx;
+        }
+        idx++;
+        binding = binding->mNext;
+    }
+
+    return -1;
+}
+
+nsBindingValues::~nsBindingValues()
+{
+    ClearBindingSet();
+    MOZ_COUNT_DTOR(nsBindingValues);
+}
+
+void
+nsBindingValues::ClearBindingSet()
+{
+    if (mBindings && mValues) {
+        delete [] mValues;
+        mValues = nullptr;
+    }
+
+    mBindings = nullptr;
+}
+
+nsresult
+nsBindingValues::SetBindingSet(RDFBindingSet* aBindings)
+{
+    ClearBindingSet();
+
+    int32_t count = aBindings->Count();
+    if (count) {
+        mValues = new nsCOMPtr<nsIRDFNode>[count];
+        mBindings = aBindings;
+    }
+    else {
+        mValues = nullptr;
+    }
+
+    return NS_OK;
+}
+
+void
+nsBindingValues::GetAssignmentFor(nsXULTemplateResultRDF* aResult,
+                                  nsIAtom* aVar,
+                                  nsIRDFNode** aValue)
+{
+    *aValue = nullptr;
+
+    // assignments are calculated lazily when asked for. The only issue is
+    // when a binding has no value in the RDF graph, it will be checked again
+    // every time.
+
+    if (mBindings && mValues) {
+        RDFBinding* binding;
+        int32_t idx = mBindings->LookupTargetIndex(aVar, &binding);
+        if (idx >= 0) {
+            *aValue = mValues[idx];
+            if (*aValue) {
+                NS_ADDREF(*aValue);
+            }
+            else {
+                nsXULTemplateQueryProcessorRDF* processor = aResult->GetProcessor();
+                if (! processor)
+                    return;
+
+                nsIRDFDataSource* ds = processor->GetDataSource();
+                if (! ds)
+                    return;
+
+                nsCOMPtr<nsIRDFNode> subjectValue;
+                aResult->GetAssignment(binding->mSubjectVariable,
+                                       getter_AddRefs(subjectValue));
+                if (subjectValue) {
+                    nsCOMPtr<nsIRDFResource> subject = do_QueryInterface(subjectValue);
+                    ds->GetTarget(subject, binding->mPredicate, true, aValue);
+                    if (*aValue)
+                        mValues[idx] = *aValue;
+                }
+            }
+        }
+    }
+}
+
+void
+nsBindingValues::RemoveDependencies(nsIRDFResource* aSubject,
+                                    nsXULTemplateResultRDF* aResult)
+{
+    if (mBindings)
+        mBindings->RemoveDependencies(aSubject, aResult);
+}