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use super::*;
use error::*;
impl Slab {
pub fn new_memo ( &self, subject_id: Option<SubjectId>, parents: MemoRefHead, body: MemoBody) -> MemoRef {
let mut counters = self.counters.write().unwrap();
counters.last_memo_id += 1;
let memo_id = (self.id as u64).rotate_left(32) | counters.last_memo_id as u64;
//println!("# Slab({}).new_memo(id: {},subject_id: {:?}, parents: {:?}, body: {:?})", self.id, memo_id, subject_id, parents.memo_ids(), body );
let memo = Memo::new(MemoInner {
id: memo_id,
owning_slab_id: self.id,
subject_id: subject_id,
parents: parents,
body: body
});
let (memoref, _had_memoref) = self.assert_memoref(memo.id, memo.subject_id, MemoPeerList(Vec::new()), Some(memo) );
self.consider_emit_memo(&memoref);
memoref
}
pub fn reconstitute_memo ( &self, memo_id: MemoId, subject_id: Option<SubjectId>, parents: MemoRefHead, body: MemoBody, origin_slabref: &SlabRef, peerlist: &MemoPeerList ) -> (Memo,MemoRef,bool){
//println!("Slab({}).reconstitute_memo({})", self.id, memo_id );
// TODO: find a way to merge this with assert_memoref to avoid doing duplicative work with regard to peerlist application
let memo = Memo::new(MemoInner {
id: memo_id,
owning_slab_id: self.id,
subject_id: subject_id,
parents: parents,
body: body
});
let (memoref, had_memoref) = self.assert_memoref(memo.id, memo.subject_id, peerlist.clone(), Some(memo.clone()) );
{
let mut counters = self.counters.write().unwrap();
counters.memos_received += 1;
if had_memoref {
counters.memos_redundantly_received += 1;
}
}
//println!("Slab({}).reconstitute_memo({}) B -> {:?}", self.id, memo_id, memoref );
self.consider_emit_memo(&memoref);
if let Some(ref memo) = memoref.get_memo_if_resident() {
self.check_memo_waiters(memo);
//TODO1 - figure out eventual consistency index update behavior. Think fairly hard about blockchain fan-in / block-tree
// NOTE: this might be a correct place to employ selective hearing. Highest liklihood if the subject is in any of our contexts,
// otherwise
self.handle_memo_from_other_slab(memo, &memoref, &origin_slabref);
self.do_peering(&memoref, &origin_slabref);
}
if let Some(ref tx_mutex) = self.memoref_dispatch_tx_channel {
tx_mutex.lock().unwrap().send(memoref.clone()).unwrap()
}
(memo, memoref, had_memoref)
}
pub fn residentize_memoref(&self, memoref: &MemoRef, memo: Memo) -> bool {
//println!("# Slab({}).MemoRef({}).residentize()", self.id, memoref.id);
assert!(memoref.owning_slab_id == self.id);
assert!( memoref.id == memo.id );
let mut ptr = memoref.ptr.write().unwrap();
if let MemoRefPtr::Remote = *ptr {
*ptr = MemoRefPtr::Resident( memo );
// should this be using do_peering_for_memo?
// doing it manually for now, because I think we might only want to do
// a concise update to reflect our peering status change
let peering_memoref = self.new_memo(
None,
memoref.to_head(),
MemoBody::Peering(
memoref.id,
memoref.subject_id,
MemoPeerList::new(vec![ MemoPeer{
slabref: self.my_ref.clone(),
status: MemoPeeringStatus::Resident
}])
)
);
for peer in memoref.peerlist.read().unwrap().iter() {
peer.slabref.send( &self.my_ref, &peering_memoref );
}
// residentized
true
}else{
// already resident
false
}
}
pub fn remotize_memoref( &self, memoref: &MemoRef ) -> Result<(),StorageOpDeclined> {
assert!(memoref.owning_slab_id == self.id);
//println!("# Slab({}).MemoRef({}).remotize()", self.id, memoref.id );
// TODO: check peering minimums here, and punt if we're below threshold
let send_peers;
{
let mut ptr = memoref.ptr.write().unwrap();
if let MemoRefPtr::Resident(_) = *ptr {
let peerlist = memoref.peerlist.read().unwrap();
if peerlist.len() == 0 {
return Err(StorageOpDeclined::InsufficientPeering);
}
send_peers = peerlist.clone();
*ptr = MemoRefPtr::Remote;
}else{
return Ok(());
}
}
let peering_memoref = self.new_memo_basic(
None,
memoref.to_head(),
MemoBody::Peering(
memoref.id,
memoref.subject_id,
MemoPeerList::new(vec![MemoPeer{
slabref: self.my_ref.clone(),
status: MemoPeeringStatus::Participating
}])
)
);
//self.consider_emit_memo(&memoref);
for peer in send_peers.iter() {
peer.slabref.send( &self.my_ref, &peering_memoref );
}
Ok(())
}
pub fn request_memo (&self, memoref: &MemoRef) -> u8 {
//println!("Slab({}).request_memo({})", self.id, memoref.id );
let request_memo = self.new_memo_basic(
None,
MemoRefHead::Null,
MemoBody::MemoRequest(
vec![memoref.id],
self.my_ref.clone()
)
);
let mut sent = 0u8;
for peer in memoref.peerlist.read().unwrap().iter().take(5) {
//println!("Slab({}).request_memo({}) from {}", self.id, memoref.id, peer.slabref.slab_id );
peer.slabref.send( &self.my_ref, &request_memo.clone() );
sent += 1;
}
sent
}
pub fn assert_memoref( &self, memo_id: MemoId, subject_id: Option<SubjectId>, peerlist: MemoPeerList, memo: Option<Memo>) -> (MemoRef, bool) {
let had_memoref;
let memoref = match self.memorefs_by_id.write().unwrap().entry(memo_id) {
Entry::Vacant(o) => {
let mr = MemoRef(Arc::new(
MemoRefInner {
id: memo_id,
owning_slab_id: self.id,
subject_id: subject_id,
peerlist: RwLock::new(peerlist),
ptr: RwLock::new(match memo {
Some(m) => {
assert!(self.id == m.owning_slab_id);
MemoRefPtr::Resident(m)
}
None => MemoRefPtr::Remote
})
}
));
had_memoref = false;
o.insert( mr ).clone()// TODO: figure out how to prolong the borrow here & avoid clone
}
Entry::Occupied(o) => {
let mr = o.get();
had_memoref = true;
if let Some(m) = memo {
let mut ptr = mr.ptr.write().unwrap();
if let MemoRefPtr::Remote = *ptr {
*ptr = MemoRefPtr::Resident(m)
}
}
mr.apply_peers( &peerlist );
mr.clone()
}
};
(memoref, had_memoref)
}
pub fn assert_slabref(&self, slab_id: SlabId, presence: &[SlabPresence] ) -> SlabRef {
//println!("# Slab({}).assert_slabref({}, {:?})", self.id, slab_id, presence );
if slab_id == self.id {
return self.my_ref.clone();
// don't even look it up if it's me.
// We must not allow any third party to edit the peering.
// Also, my ref won't appeara in the list of peer_refs, because it's not a peer
}
let maybe_slabref = {
// Instead of having to scope our read lock, and getting a write lock later
// should we be using a single write lock for the full function scope?
if let Some(slabref) = self.peer_refs.read().expect("peer_refs.read()").iter().find(|r| r.0.slab_id == slab_id ){
Some(slabref.clone())
}else{
None
}
};
let slabref : SlabRef;
if let Some(s) = maybe_slabref {
slabref = s;
}else{
let inner = SlabRefInner {
slab_id: slab_id,
owning_slab_id: self.id, // for assertions only?
presence: RwLock::new(Vec::new()),
tx: Mutex::new(Transmitter::new_blackhole(slab_id)),
return_address: RwLock::new(TransportAddress::Blackhole),
};
slabref = SlabRef(Arc::new(inner));
self.peer_refs.write().expect("peer_refs.write()").push(slabref.clone());
}
if slab_id == slabref.owning_slab_id {
return slabref; // no funny business. You don't get to tell me how to reach me
}
for p in presence.iter(){
assert!(slab_id == p.slab_id, "presence slab_id does not match the provided slab_id");
let mut _maybe_slab = None;
let args = if p.address.is_local() {
// playing silly games with borrow lifetimes.
// TODO: make this less ugly
_maybe_slab = self.net.get_slab(p.slab_id);
if let Some(ref slab) = _maybe_slab {
TransmitterArgs::Local(slab)
}else{
continue;
}
}else{
TransmitterArgs::Remote( &p.slab_id, &p.address )
};
// Returns true if this presence is new to the slabref
// False if we've seen this presence already
if slabref.apply_presence(p) {
let new_trans = self.net.get_transmitter( &args ).expect("assert_slabref net.get_transmitter");
let return_address = self.net.get_return_address( &p.address ).expect("return address not found");
*slabref.0.tx.lock().expect("tx.lock()") = new_trans;
*slabref.0.return_address.write().expect("return_address write lock") = return_address;
}
}
return slabref;
}
}