gecko-dev/rdf/base/nsRDFContainerUtils.cpp

514 строки
14 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/. */
/*
Implementation for the RDF container utils.
*/
#include "nsCOMPtr.h"
#include "nsIServiceManager.h"
#include "nsIRDFContainer.h"
#include "nsIRDFContainerUtils.h"
#include "nsIRDFService.h"
#include "nsRDFCID.h"
#include "nsString.h"
#include "plstr.h"
#include "rdf.h"
#include "rdfutil.h"
class RDFContainerUtilsImpl : public nsIRDFContainerUtils
{
public:
// nsISupports interface
NS_DECL_ISUPPORTS
// nsIRDFContainerUtils interface
NS_DECL_NSIRDFCONTAINERUTILS
private:
friend nsresult NS_NewRDFContainerUtils(nsIRDFContainerUtils** aResult);
RDFContainerUtilsImpl();
virtual ~RDFContainerUtilsImpl();
nsresult MakeContainer(nsIRDFDataSource* aDataSource,
nsIRDFResource* aResource,
nsIRDFResource* aType,
nsIRDFContainer** aResult);
bool IsA(nsIRDFDataSource* aDataSource, nsIRDFResource* aResource, nsIRDFResource* aType);
// pseudo constants
static int32_t gRefCnt;
static nsIRDFService* gRDFService;
static nsIRDFResource* kRDF_instanceOf;
static nsIRDFResource* kRDF_nextVal;
static nsIRDFResource* kRDF_Bag;
static nsIRDFResource* kRDF_Seq;
static nsIRDFResource* kRDF_Alt;
static nsIRDFLiteral* kOne;
static const char kRDFNameSpaceURI[];
};
int32_t RDFContainerUtilsImpl::gRefCnt = 0;
nsIRDFService* RDFContainerUtilsImpl::gRDFService;
nsIRDFResource* RDFContainerUtilsImpl::kRDF_instanceOf;
nsIRDFResource* RDFContainerUtilsImpl::kRDF_nextVal;
nsIRDFResource* RDFContainerUtilsImpl::kRDF_Bag;
nsIRDFResource* RDFContainerUtilsImpl::kRDF_Seq;
nsIRDFResource* RDFContainerUtilsImpl::kRDF_Alt;
nsIRDFLiteral* RDFContainerUtilsImpl::kOne;
const char RDFContainerUtilsImpl::kRDFNameSpaceURI[] = RDF_NAMESPACE_URI;
////////////////////////////////////////////////////////////////////////
// nsISupports interface
NS_IMPL_ISUPPORTS(RDFContainerUtilsImpl, nsIRDFContainerUtils)
////////////////////////////////////////////////////////////////////////
// nsIRDFContainerUtils interface
NS_IMETHODIMP
RDFContainerUtilsImpl::IsOrdinalProperty(nsIRDFResource *aProperty, bool *_retval)
{
NS_PRECONDITION(aProperty != nullptr, "null ptr");
if (! aProperty)
return NS_ERROR_NULL_POINTER;
nsresult rv;
const char *propertyStr;
rv = aProperty->GetValueConst( &propertyStr );
if (NS_FAILED(rv)) return rv;
if (PL_strncmp(propertyStr, kRDFNameSpaceURI, sizeof(kRDFNameSpaceURI) - 1) != 0) {
*_retval = false;
return NS_OK;
}
const char* s = propertyStr;
s += sizeof(kRDFNameSpaceURI) - 1;
if (*s != '_') {
*_retval = false;
return NS_OK;
}
++s;
while (*s) {
if (*s < '0' || *s > '9') {
*_retval = false;
return NS_OK;
}
++s;
}
*_retval = true;
return NS_OK;
}
NS_IMETHODIMP
RDFContainerUtilsImpl::IndexToOrdinalResource(int32_t aIndex, nsIRDFResource **aOrdinal)
{
NS_PRECONDITION(aIndex > 0, "illegal value");
if (aIndex <= 0)
return NS_ERROR_ILLEGAL_VALUE;
nsAutoCString uri(kRDFNameSpaceURI);
uri.Append('_');
uri.AppendInt(aIndex);
nsresult rv = gRDFService->GetResource(uri, aOrdinal);
NS_ASSERTION(NS_SUCCEEDED(rv), "unable to get ordinal resource");
if (NS_FAILED(rv)) return rv;
return NS_OK;
}
NS_IMETHODIMP
RDFContainerUtilsImpl::OrdinalResourceToIndex(nsIRDFResource *aOrdinal, int32_t *aIndex)
{
NS_PRECONDITION(aOrdinal != nullptr, "null ptr");
if (! aOrdinal)
return NS_ERROR_NULL_POINTER;
const char *ordinalStr;
if (NS_FAILED(aOrdinal->GetValueConst( &ordinalStr )))
return NS_ERROR_FAILURE;
const char* s = ordinalStr;
if (PL_strncmp(s, kRDFNameSpaceURI, sizeof(kRDFNameSpaceURI) - 1) != 0) {
NS_ERROR("not an ordinal");
return NS_ERROR_UNEXPECTED;
}
s += sizeof(kRDFNameSpaceURI) - 1;
if (*s != '_') {
NS_ERROR("not an ordinal");
return NS_ERROR_UNEXPECTED;
}
int32_t idx = 0;
++s;
while (*s) {
if (*s < '0' || *s > '9') {
NS_ERROR("not an ordinal");
return NS_ERROR_UNEXPECTED;
}
idx *= 10;
idx += (*s - '0');
++s;
}
*aIndex = idx;
return NS_OK;
}
NS_IMETHODIMP
RDFContainerUtilsImpl::IsContainer(nsIRDFDataSource *aDataSource, nsIRDFResource *aResource, bool *_retval)
{
NS_PRECONDITION(aDataSource != nullptr, "null ptr");
if (! aDataSource)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aResource != nullptr, "null ptr");
if (! aResource)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(_retval != nullptr, "null ptr");
if (! _retval)
return NS_ERROR_NULL_POINTER;
if (IsA(aDataSource, aResource, kRDF_Seq) ||
IsA(aDataSource, aResource, kRDF_Bag) ||
IsA(aDataSource, aResource, kRDF_Alt)) {
*_retval = true;
}
else {
*_retval = false;
}
return NS_OK;
}
NS_IMETHODIMP
RDFContainerUtilsImpl::IsEmpty(nsIRDFDataSource* aDataSource, nsIRDFResource* aResource, bool* _retval)
{
if (! aDataSource)
return NS_ERROR_NULL_POINTER;
nsresult rv;
// By default, say that we're an empty container. Even if we're not
// really even a container.
*_retval = true;
nsCOMPtr<nsIRDFNode> nextValNode;
rv = aDataSource->GetTarget(aResource, kRDF_nextVal, true, getter_AddRefs(nextValNode));
if (NS_FAILED(rv)) return rv;
if (rv == NS_RDF_NO_VALUE)
return NS_OK;
nsCOMPtr<nsIRDFLiteral> nextValLiteral;
rv = nextValNode->QueryInterface(NS_GET_IID(nsIRDFLiteral), getter_AddRefs(nextValLiteral));
if (NS_FAILED(rv)) return rv;
if (nextValLiteral.get() != kOne)
*_retval = false;
return NS_OK;
}
NS_IMETHODIMP
RDFContainerUtilsImpl::IsBag(nsIRDFDataSource *aDataSource, nsIRDFResource *aResource, bool *_retval)
{
NS_PRECONDITION(aDataSource != nullptr, "null ptr");
if (! aDataSource)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aResource != nullptr, "null ptr");
if (! aResource)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(_retval != nullptr, "null ptr");
if (! _retval)
return NS_ERROR_NULL_POINTER;
*_retval = IsA(aDataSource, aResource, kRDF_Bag);
return NS_OK;
}
NS_IMETHODIMP
RDFContainerUtilsImpl::IsSeq(nsIRDFDataSource *aDataSource, nsIRDFResource *aResource, bool *_retval)
{
NS_PRECONDITION(aDataSource != nullptr, "null ptr");
if (! aDataSource)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aResource != nullptr, "null ptr");
if (! aResource)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(_retval != nullptr, "null ptr");
if (! _retval)
return NS_ERROR_NULL_POINTER;
*_retval = IsA(aDataSource, aResource, kRDF_Seq);
return NS_OK;
}
NS_IMETHODIMP
RDFContainerUtilsImpl::IsAlt(nsIRDFDataSource *aDataSource, nsIRDFResource *aResource, bool *_retval)
{
NS_PRECONDITION(aDataSource != nullptr, "null ptr");
if (! aDataSource)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aResource != nullptr, "null ptr");
if (! aResource)
return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(_retval != nullptr, "null ptr");
if (! _retval)
return NS_ERROR_NULL_POINTER;
*_retval = IsA(aDataSource, aResource, kRDF_Alt);
return NS_OK;
}
NS_IMETHODIMP
RDFContainerUtilsImpl::MakeBag(nsIRDFDataSource *aDataSource, nsIRDFResource *aResource, nsIRDFContainer **_retval)
{
return MakeContainer(aDataSource, aResource, kRDF_Bag, _retval);
}
NS_IMETHODIMP
RDFContainerUtilsImpl::MakeSeq(nsIRDFDataSource *aDataSource, nsIRDFResource *aResource, nsIRDFContainer **_retval)
{
return MakeContainer(aDataSource, aResource, kRDF_Seq, _retval);
}
NS_IMETHODIMP
RDFContainerUtilsImpl::MakeAlt(nsIRDFDataSource *aDataSource, nsIRDFResource *aResource, nsIRDFContainer **_retval)
{
return MakeContainer(aDataSource, aResource, kRDF_Alt, _retval);
}
////////////////////////////////////////////////////////////////////////
RDFContainerUtilsImpl::RDFContainerUtilsImpl()
{
if (gRefCnt++ == 0) {
nsresult rv;
NS_DEFINE_CID(kRDFServiceCID, NS_RDFSERVICE_CID);
rv = CallGetService(kRDFServiceCID, &gRDFService);
NS_ASSERTION(NS_SUCCEEDED(rv), "unable to get RDF service");
if (NS_SUCCEEDED(rv)) {
gRDFService->GetResource(NS_LITERAL_CSTRING(RDF_NAMESPACE_URI "instanceOf"),
&kRDF_instanceOf);
gRDFService->GetResource(NS_LITERAL_CSTRING(RDF_NAMESPACE_URI "nextVal"),
&kRDF_nextVal);
gRDFService->GetResource(NS_LITERAL_CSTRING(RDF_NAMESPACE_URI "Bag"),
&kRDF_Bag);
gRDFService->GetResource(NS_LITERAL_CSTRING(RDF_NAMESPACE_URI "Seq"),
&kRDF_Seq);
gRDFService->GetResource(NS_LITERAL_CSTRING(RDF_NAMESPACE_URI "Alt"),
&kRDF_Alt);
gRDFService->GetLiteral(u"1", &kOne);
}
}
}
RDFContainerUtilsImpl::~RDFContainerUtilsImpl()
{
#ifdef DEBUG_REFS
--gInstanceCount;
fprintf(stdout, "%d - RDF: RDFContainerUtilsImpl\n", gInstanceCount);
#endif
if (--gRefCnt == 0) {
NS_IF_RELEASE(gRDFService);
NS_IF_RELEASE(kRDF_instanceOf);
NS_IF_RELEASE(kRDF_nextVal);
NS_IF_RELEASE(kRDF_Bag);
NS_IF_RELEASE(kRDF_Seq);
NS_IF_RELEASE(kRDF_Alt);
NS_IF_RELEASE(kOne);
}
}
nsresult
NS_NewRDFContainerUtils(nsIRDFContainerUtils** aResult)
{
NS_PRECONDITION(aResult != nullptr, "null ptr");
if (! aResult)
return NS_ERROR_NULL_POINTER;
RDFContainerUtilsImpl* result =
new RDFContainerUtilsImpl();
if (! result)
return NS_ERROR_OUT_OF_MEMORY;
NS_ADDREF(result);
*aResult = result;
return NS_OK;
}
nsresult
RDFContainerUtilsImpl::MakeContainer(nsIRDFDataSource* aDataSource, nsIRDFResource* aResource, nsIRDFResource* aType, nsIRDFContainer** aResult)
{
NS_PRECONDITION(aDataSource != nullptr, "null ptr");
if (! aDataSource) return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aResource != nullptr, "null ptr");
if (! aResource) return NS_ERROR_NULL_POINTER;
NS_PRECONDITION(aType != nullptr, "null ptr");
if (! aType) return NS_ERROR_NULL_POINTER;
if (aResult) *aResult = nullptr;
nsresult rv;
// Check to see if somebody has already turned it into a container; if so
// don't try to do it again.
bool isContainer;
rv = IsContainer(aDataSource, aResource, &isContainer);
if (NS_FAILED(rv)) return rv;
if (!isContainer)
{
rv = aDataSource->Assert(aResource, kRDF_instanceOf, aType, true);
if (NS_FAILED(rv)) return rv;
rv = aDataSource->Assert(aResource, kRDF_nextVal, kOne, true);
if (NS_FAILED(rv)) return rv;
}
if (aResult) {
rv = NS_NewRDFContainer(aResult);
if (NS_FAILED(rv)) return rv;
rv = (*aResult)->Init(aDataSource, aResource);
if (NS_FAILED(rv)) return rv;
}
return NS_OK;
}
bool
RDFContainerUtilsImpl::IsA(nsIRDFDataSource* aDataSource, nsIRDFResource* aResource, nsIRDFResource* aType)
{
if (!aDataSource || !aResource || !aType) {
NS_WARNING("Unexpected null argument");
return false;
}
nsresult rv;
bool result;
rv = aDataSource->HasAssertion(aResource, kRDF_instanceOf, aType, true, &result);
if (NS_FAILED(rv))
return false;
return result;
}
NS_IMETHODIMP
RDFContainerUtilsImpl::IndexOf(nsIRDFDataSource* aDataSource, nsIRDFResource* aContainer, nsIRDFNode* aElement, int32_t* aIndex)
{
if (!aDataSource || !aContainer)
return NS_ERROR_NULL_POINTER;
// Assume we can't find it.
*aIndex = -1;
// If the resource is null, bail quietly
if (! aElement)
return NS_OK;
// We'll assume that fan-out is much higher than fan-in, so grovel
// through the inbound arcs, look for an ordinal resource, and
// decode it.
nsCOMPtr<nsISimpleEnumerator> arcsIn;
aDataSource->ArcLabelsIn(aElement, getter_AddRefs(arcsIn));
if (! arcsIn)
return NS_OK;
while (1) {
bool hasMoreArcs = false;
arcsIn->HasMoreElements(&hasMoreArcs);
if (! hasMoreArcs)
break;
nsCOMPtr<nsISupports> isupports;
arcsIn->GetNext(getter_AddRefs(isupports));
if (! isupports)
break;
nsCOMPtr<nsIRDFResource> property =
do_QueryInterface(isupports);
if (! property)
continue;
bool isOrdinal;
IsOrdinalProperty(property, &isOrdinal);
if (! isOrdinal)
continue;
nsCOMPtr<nsISimpleEnumerator> sources;
aDataSource->GetSources(property, aElement, true, getter_AddRefs(sources));
if (! sources)
continue;
while (1) {
bool hasMoreSources = false;
sources->HasMoreElements(&hasMoreSources);
if (! hasMoreSources)
break;
nsCOMPtr<nsISupports> isupports2;
sources->GetNext(getter_AddRefs(isupports2));
if (! isupports2)
break;
nsCOMPtr<nsIRDFResource> source =
do_QueryInterface(isupports2);
if (source == aContainer)
// Found it.
return OrdinalResourceToIndex(property, aIndex);
}
}
return NS_OK;
}