gecko-dev/dom/xul/templates/nsInstantiationNode.cpp

84 lines
3.0 KiB
C++

/* -*- 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 "nsInstantiationNode.h"
#include "nsTemplateRule.h"
#include "nsXULTemplateQueryProcessorRDF.h"
#include "mozilla/Logging.h"
extern PRLogModuleInfo* gXULTemplateLog;
nsInstantiationNode::nsInstantiationNode(nsXULTemplateQueryProcessorRDF* aProcessor,
nsRDFQuery* aQuery)
: mProcessor(aProcessor),
mQuery(aQuery)
{
MOZ_LOG(gXULTemplateLog, PR_LOG_DEBUG,
("nsInstantiationNode[%p] query=%p", this, aQuery));
MOZ_COUNT_CTOR(nsInstantiationNode);
}
nsInstantiationNode::~nsInstantiationNode()
{
MOZ_COUNT_DTOR(nsInstantiationNode);
}
nsresult
nsInstantiationNode::Propagate(InstantiationSet& aInstantiations,
bool aIsUpdate, bool& aTakenInstantiations)
{
// In update mode, iterate through the results and call the template
// builder to update them. In non-update mode, cache them in the processor
// to be used during processing. The results are cached in the processor
// so that the simple rules are only computed once. In this situation, all
// data for all queries are calculated at once.
nsresult rv = NS_OK;
aTakenInstantiations = false;
if (aIsUpdate) {
// Iterate through newly added keys to determine which rules fired.
//
// XXXwaterson Unfortunately, this could also lead to retractions;
// e.g., (container ?a ^empty false) could become "unmatched". How
// to track those?
nsCOMPtr<nsIDOMNode> querynode;
mQuery->GetQueryNode(getter_AddRefs(querynode));
InstantiationSet::ConstIterator last = aInstantiations.Last();
for (InstantiationSet::ConstIterator inst = aInstantiations.First(); inst != last; ++inst) {
nsAssignmentSet assignments = inst->mAssignments;
nsCOMPtr<nsIRDFNode> node;
assignments.GetAssignmentFor(mQuery->mMemberVariable,
getter_AddRefs(node));
if (node) {
nsCOMPtr<nsIRDFResource> resource = do_QueryInterface(node);
if (resource) {
nsRefPtr<nsXULTemplateResultRDF> nextresult =
new nsXULTemplateResultRDF(mQuery, *inst, resource);
if (! nextresult)
return NS_ERROR_OUT_OF_MEMORY;
rv = mProcessor->AddMemoryElements(*inst, nextresult);
if (NS_FAILED(rv))
return rv;
mProcessor->GetBuilder()->AddResult(nextresult, querynode);
}
}
}
}
else {
nsresult rv = mQuery->SetCachedResults(mProcessor, aInstantiations);
if (NS_SUCCEEDED(rv))
aTakenInstantiations = true;
}
return rv;
}