// The takeCensus function works in three phases:
//
// 1) We examine the 'breakdown' property of our 'options' argument, and
// use that to build a CountType tree.
//
// 2) We create a count node for the root of our CountType tree, and then walk
// the heap, counting each node we find, expanding our tree of counts as we
// go.
//
// 3) We walk the tree of counts and produce JavaScript objects reporting the
// accumulated results.
bool
DebuggerMemory::takeCensus(JSContext* cx, unsigned argc, Value* vp)
{
THIS_DEBUGGER_MEMORY(cx, argc, vp, "Debugger.Memory.prototype.census", args, memory);
Census census(cx);
if (!census.init())
return false;
CountTypePtr rootType;
RootedObject options(cx);
if (args.get(0).isObject())
options = &args[0].toObject();
if (!JS::ubi::ParseCensusOptions(cx, census, options, rootType))
return false;
JS::ubi::RootedCount rootCount(cx, rootType->makeCount());
if (!rootCount)
return false;
JS::ubi::CensusHandler handler(census, rootCount, cx->runtime()->debuggerMallocSizeOf);
Debugger* dbg = memory->getDebugger();
RootedObject dbgObj(cx, dbg->object);
// Populate our target set of debuggee zones.
for (WeakGlobalObjectSet::Range r = dbg->allDebuggees(); !r.empty(); r.popFront()) {
if (!census.targetZones.put(r.front()->zone()))
return false;
}
{
Maybe<JS::AutoCheckCannotGC> maybeNoGC;
JS::ubi::RootList rootList(cx->runtime(), maybeNoGC);
if (!rootList.init(dbgObj)) {
ReportOutOfMemory(cx);
return false;
}
JS::ubi::CensusTraversal traversal(cx->runtime(), handler, maybeNoGC.ref());
if (!traversal.init()) {
ReportOutOfMemory(cx);
return false;
}
traversal.wantNames = false;
if (!traversal.addStart(JS::ubi::Node(&rootList)) ||
!traversal.traverse())
{
ReportOutOfMemory(cx);
return false;
}
}
return handler.report(cx, args.rval());
}
