private void startTraversal(SMGObject pObject) {
if (candidates.containsKey(pObject)) {
// Processed already in continueTraversal
return;
}
candidates.put(pObject, new HashMap<Integer, SMGSingleLinkedListCandidate>());
for (SMGEdgeHasValue hv : smg.getHVEdges(SMGEdgeHasValueFilter.objectFilter(pObject))) {
if (smg.isPointer(hv.getValue())) {
SMGSingleLinkedListCandidate candidate =
new SMGSingleLinkedListCandidate(pObject, hv.getOffset(), 1);
candidates.get(pObject).put(hv.getOffset(), candidate);
continueTraversal(hv.getValue(), candidate);
}
}
}
@Test
public void simpleListTest() {
CLangSMG smg = new CLangSMG(MachineModel.LINUX64);
SMGEdgeHasValue root = TestHelpers.createGlobalList(smg, 5, 16, 8, "pointer");
SMGSingleLinkedListFinder finder = new SMGSingleLinkedListFinder(1);
Set<SMGAbstractionCandidate> candidates = finder.traverse(smg);
Assert.assertEquals(1, candidates.size());
SMGAbstractionCandidate candidate = Iterables.getOnlyElement(candidates);
Assert.assertTrue(candidate instanceof SMGSingleLinkedListCandidate);
SMGSingleLinkedListCandidate sllCandidate = (SMGSingleLinkedListCandidate) candidate;
Assert.assertEquals(5, sllCandidate.getLength());
Assert.assertEquals(8, sllCandidate.getOffset());
SMGRegion expectedStart = (SMGRegion) smg.getPointer(root.getValue()).getObject();
Assert.assertSame(expectedStart, sllCandidate.getStart());
}
@Test
public void listWithInboundPointersTest() {
CLangSMG smg = new CLangSMG(MachineModel.LINUX64);
Integer tail = TestHelpers.createList(smg, 4, 16, 8, "tail");
SMGEdgeHasValue head = TestHelpers.createGlobalList(smg, 3, 16, 8, "head");
SMGObject inside = new SMGRegion(16, "pointed_at");
SMGEdgeHasValue tailConnection =
new SMGEdgeHasValue(AnonymousTypes.dummyPointer, 8, inside, tail);
Integer addressOfInside = SMGValueFactory.getNewValue();
SMGEdgePointsTo insidePT = new SMGEdgePointsTo(addressOfInside, inside, 0);
SMGRegion inboundPointer = new SMGRegion(8, "inbound_pointer");
SMGEdgeHasValue inboundPointerConnection =
new SMGEdgeHasValue(AnonymousTypes.dummyPointer, 0, inboundPointer, addressOfInside);
SMGObject lastFromHead = smg.getPointer(head.getValue()).getObject();
SMGEdgeHasValue connection = null;
do {
SMGEdgeHasValueFilter filter =
SMGEdgeHasValueFilter.objectFilter(lastFromHead).filterAtOffset(8);
Set<SMGEdgeHasValue> connections = smg.getHVEdges(filter);
connection = null;
if (connections.size() > 0) {
connection = Iterables.getOnlyElement(connections);
lastFromHead = smg.getPointer(connection.getValue()).getObject();
}
} while (connection != null);
for (SMGEdgeHasValue hv : smg.getHVEdges(SMGEdgeHasValueFilter.objectFilter(lastFromHead))) {
smg.removeHasValueEdge(hv);
}
SMGEdgeHasValue headConnection =
new SMGEdgeHasValue(AnonymousTypes.dummyPointer, 8, lastFromHead, addressOfInside);
SMGRegion tailPointer = new SMGRegion(8, "tail_pointer");
SMGEdgeHasValue tailPointerConnection =
new SMGEdgeHasValue(AnonymousTypes.dummyPointer, 0, tailPointer, tail);
smg.addGlobalObject(tailPointer);
smg.addHasValueEdge(tailPointerConnection);
smg.addHeapObject(inside);
smg.addValue(addressOfInside);
smg.addPointsToEdge(insidePT);
smg.addGlobalObject(inboundPointer);
smg.addHasValueEdge(inboundPointerConnection);
smg.addHasValueEdge(tailConnection);
smg.addHasValueEdge(headConnection);
SMGSingleLinkedListFinder finder = new SMGSingleLinkedListFinder(1);
Set<SMGAbstractionCandidate> candidates = finder.traverse(smg);
Assert.assertEquals(2, candidates.size());
boolean sawHead = false;
boolean sawTail = false;
for (SMGAbstractionCandidate candidate : candidates) {
SMGSingleLinkedListCandidate sllCandidate = (SMGSingleLinkedListCandidate) candidate;
if (sllCandidate.getLength() == 3) {
Assert.assertSame(smg.getPointer(head.getValue()).getObject(), sllCandidate.getStart());
Assert.assertFalse(sawHead);
sawHead = true;
} else if (sllCandidate.getLength() == 4) {
Assert.assertSame(smg.getPointer(tail).getObject(), sllCandidate.getStart());
Assert.assertFalse(sawTail);
} else {
Assert.fail("We should not see any candidates with length other than 3 or 4");
}
}
}