diff -r 000000000000 -r 6474c204b198 rdf/tests/rdfpoll/rdfpoll.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/rdf/tests/rdfpoll/rdfpoll.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,270 @@
+/* -*- 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/. */
+
+/*
+
+  A simple test program that reads in RDF/XML into an in-memory data
+  source, then periodically updates it. It prints the messages
+  indicating assert and unassert activity to the console.
+
+  The program takes two parameters: the URL from which to read, and
+  the poll-interval at which to re-load the .
+
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include "nsXPCOM.h"
+#include "nsCOMPtr.h"
+#include "nsIInputStream.h"
+#include "nsIIOService.h"
+#include "nsIRDFCompositeDataSource.h"
+#include "nsIRDFRemoteDataSource.h"
+#include "nsIRDFNode.h"
+#include "nsIRDFService.h"
+#include "nsIRDFXMLSource.h"
+#include "nsIServiceManager.h"
+#include "nsServiceManagerUtils.h"
+#include "nsIStreamListener.h"
+#include "nsIURL.h"
+#include "nsRDFCID.h"
+#include "nsIComponentManager.h"
+#include "nsComponentManagerUtils.h"
+#include "nsThreadUtils.h"
+#include "prthread.h"
+#include "plstr.h"
+#include "nsEmbedString.h"
+#include "nsNetCID.h"
+#include "prtime.h"
+
+////////////////////////////////////////////////////////////////////////
+// CIDs
+
+// rdf
+static NS_DEFINE_CID(kRDFXMLDataSourceCID,  NS_RDFXMLDATASOURCE_CID);
+
+////////////////////////////////////////////////////////////////////////
+// IIDs
+
+
+#include "nsIMemory.h" // for the CID
+
+////////////////////////////////////////////////////////////////////////
+
+class Observer : public nsIRDFObserver
+{
+public:
+    Observer();
+    virtual ~Observer() {}
+
+    // nsISupports interface
+    NS_DECL_ISUPPORTS
+
+    // nsIRDFObserver interface
+    NS_DECL_NSIRDFOBSERVER
+};
+
+Observer::Observer()
+{
+}
+
+NS_IMPL_ISUPPORTS(Observer, nsIRDFObserver)
+
+static nsresult
+rdf_WriteOp(const char* aOp,
+            nsIRDFResource* aSource,
+            nsIRDFResource* aProperty,
+            nsIRDFNode* aTarget)
+{
+    nsresult rv;
+
+    nsCString source;
+    rv = aSource->GetValue(getter_Copies(source));
+    if (NS_FAILED(rv)) return rv;
+
+    nsCString property;
+    rv = aProperty->GetValue(getter_Copies(property));
+    if (NS_FAILED(rv)) return rv;
+
+    nsCOMPtr<nsIRDFResource> resource;
+    nsCOMPtr<nsIRDFLiteral> literal;
+    nsCOMPtr<nsIRDFDate> date;
+    nsCOMPtr<nsIRDFInt> number;
+
+    printf("%.8s [%s]\n", aOp, source.get());
+    printf("       --[%s]--\n", property.get());
+
+    if ((resource = do_QueryInterface(aTarget)) != nullptr) {
+        nsCString target;
+        rv = resource->GetValue(getter_Copies(target));
+        if (NS_FAILED(rv)) return rv;
+
+        printf("       ->[%s]\n", target.get());
+    }
+    else if ((literal = do_QueryInterface(aTarget)) != nullptr) {
+        nsString target;
+        rv = literal->GetValue(getter_Copies(target));
+        if (NS_FAILED(rv)) return rv;
+
+        printf("       ->\"%s\"\n", NS_ConvertUTF16toUTF8(target).get());
+    }
+    else if ((date = do_QueryInterface(aTarget)) != nullptr) {
+        PRTime value;
+        date->GetValue(&value);
+
+        PRExplodedTime t;
+        PR_ExplodeTime(value, PR_GMTParameters, &t);
+
+        printf("       -> %02d/%02d/%04d %02d:%02d:%02d +%06d\n",
+               t.tm_month + 1,
+               t.tm_mday,
+               t.tm_year,
+               t.tm_hour,
+               t.tm_min,
+               t.tm_sec,
+               t.tm_usec);
+    }
+    else if ((number = do_QueryInterface(aTarget)) != nullptr) {
+        int32_t value;
+        number->GetValue(&value);
+
+        printf("       -> %d\n", value);
+    }
+    else {
+        printf("       -> (unknown node type)\n");
+    }
+
+    printf("\n");
+    return NS_OK;
+}
+
+NS_IMETHODIMP
+Observer::OnAssert(nsIRDFDataSource* aDataSource,
+                   nsIRDFResource* aSource,
+                   nsIRDFResource* aProperty,
+                   nsIRDFNode* aTarget)
+{
+    return rdf_WriteOp("assert", aSource, aProperty, aTarget);
+}
+
+
+NS_IMETHODIMP
+Observer::OnUnassert(nsIRDFDataSource* aDataSource,
+                     nsIRDFResource* aSource,
+                     nsIRDFResource* aProperty,
+                     nsIRDFNode* aTarget)
+{
+    return rdf_WriteOp("unassert", aSource, aProperty, aTarget);
+}
+
+
+NS_IMETHODIMP
+Observer::OnChange(nsIRDFDataSource* aDataSource,
+                   nsIRDFResource* aSource,
+                   nsIRDFResource* aProperty,
+                   nsIRDFNode* aOldTarget,
+                   nsIRDFNode* aNewTarget)
+{
+    nsresult rv;
+    rv = rdf_WriteOp("chg-from", aSource, aProperty, aOldTarget);
+    if (NS_FAILED(rv)) return rv;
+
+    rv = rdf_WriteOp("chg-to", aSource, aProperty, aNewTarget);
+    if (NS_FAILED(rv)) return rv;
+
+    return NS_OK;
+}
+
+NS_IMETHODIMP
+Observer::OnMove(nsIRDFDataSource* aDataSource,
+                 nsIRDFResource* aOldSource,
+                 nsIRDFResource* aNewSource,
+                 nsIRDFResource* aProperty,
+                 nsIRDFNode* aTarget)
+{
+    nsresult rv;
+    rv = rdf_WriteOp("mv-from", aOldSource, aProperty, aTarget);
+    if (NS_FAILED(rv)) return rv;
+
+    rv = rdf_WriteOp("mv-to", aNewSource, aProperty, aTarget);
+    if (NS_FAILED(rv)) return rv;
+
+    return NS_OK;
+}
+
+NS_IMETHODIMP
+Observer::OnBeginUpdateBatch(nsIRDFDataSource* aDataSource)
+{
+    return NS_OK;
+}
+
+NS_IMETHODIMP
+Observer::OnEndUpdateBatch(nsIRDFDataSource* aDataSource)
+{
+    return NS_OK;
+}
+
+////////////////////////////////////////////////////////////////////////
+
+int
+main(int argc, char** argv)
+{
+    nsresult rv;
+
+    if (argc < 2) {
+        fprintf(stderr, "usage: %s <url> [<poll-interval>]\n", argv[0]);
+        return 1;
+    }
+
+    rv = NS_InitXPCOM2(nullptr, nullptr, nullptr);
+    if (NS_FAILED(rv)) {
+        fprintf(stderr, "NS_InitXPCOM2 failed\n");
+        return 1;
+    }
+
+    // Create a stream data source and initialize it on argv[1], which
+    // is hopefully a "file:" URL. (Actually, we can do _any_ kind of
+    // URL, but only a "file:" URL will be written back to disk.)
+    nsCOMPtr<nsIRDFDataSource> ds = do_CreateInstance(kRDFXMLDataSourceCID, &rv);
+    if (NS_FAILED(rv)) {
+        NS_ERROR("unable to create RDF/XML data source");
+        return 1;
+    }
+
+    nsCOMPtr<nsIRDFRemoteDataSource> remote = do_QueryInterface(ds);
+    if (! remote)
+        return 1;
+
+    rv = remote->Init(argv[1]);
+    NS_ASSERTION(NS_SUCCEEDED(rv), "unable to initialize data source");
+    if (NS_FAILED(rv)) return 1;
+
+    // The do_QI() on the pointer is a hack to make sure that the new
+    // object gets AddRef()-ed.
+    nsCOMPtr<nsIRDFObserver> observer = do_QueryInterface(new Observer);
+    if (! observer)
+        return 1;
+
+    rv = ds->AddObserver(observer);
+    if (NS_FAILED(rv)) return 1;
+
+    while (1) {
+        // Okay, this should load the XML file...
+        rv = remote->Refresh(true);
+        NS_ASSERTION(NS_SUCCEEDED(rv), "unable to open datasource");
+        if (NS_FAILED(rv)) return 1;
+
+        if (argc <= 2)
+            break;
+
+        int32_t pollinterval = atol(argv[2]);
+        if (! pollinterval)
+            break;
+
+        PR_Sleep(PR_SecondsToInterval(pollinterval));
+    }
+
+    return 0;
+}