SkPicture::~SkPicture() {
// TODO: move this to ~SkBigPicture() only?
// If the ID is still zero, no one has read it, so no need to send this message.
uint32_t id = sk_atomic_load(&fUniqueID, sk_memory_order_relaxed);
if (id != 0) {
SkPicture::DeletionMessage msg = { (int32_t)id };
SkMessageBus<SkPicture::DeletionMessage>::Post(msg);
}
}
uint32_t SkPicture::uniqueID() const {
static uint32_t gNextID = 1;
uint32_t id = sk_atomic_load(&fUniqueID, sk_memory_order_relaxed);
while (id == 0) {
uint32_t next = sk_atomic_fetch_add(&gNextID, 1u);
if (sk_atomic_compare_exchange(&fUniqueID, &id, next,
sk_memory_order_relaxed,
sk_memory_order_relaxed)) {
id = next;
} else {
// sk_atomic_compare_exchange replaced id with the current value of fUniqueID.
}
}
return id;
}
SkEventTracer* SkEventTracer::GetInstance() {
if (SkEventTracer* tracer = sk_atomic_load(&gUserTracer, sk_memory_order_acquire)) {
return tracer;
}
return gDefaultTracer.get();
}
void SkEventTracer::SetInstance(SkEventTracer* tracer) {
SkASSERT(nullptr == sk_atomic_load(&gUserTracer, sk_memory_order_acquire));
sk_atomic_store(&gUserTracer, tracer, sk_memory_order_release);
// An atomic load during process shutdown is probably overkill, but safe overkill.
atexit([](){ SkDELETE(sk_atomic_load(&gUserTracer, sk_memory_order_acquire)); });
}
