public void OnDhtGetReturns(IAsyncResult result)
{
AsyncResult ar = (AsyncResult)result;
AsyncFragsOpState agfs = (AsyncFragsOpState)ar.AsyncState;
BrunetDhtGetOp op = (BrunetDhtGetOp)ar.AsyncDelegate;
AsyncGetFragsGlobalState global_state =
(AsyncGetFragsGlobalState)agfs.GlobalState;
AsyncOpState piece_state = agfs.PieceState;
DhtGetResult[] returns = op.EndInvoke(ar);
if (returns != null && returns.Length > 0)
{
// We only need the first one.
DhtGetResult dgr = returns[0];
Logger.WriteLineIf(LogLevel.Verbose, _log_props,
string.Format("Get succeeded for piece: {0}",
Encoding.UTF8.GetString(piece_state.Key)));
lock (global_state.SyncRoot) {
byte[] piece_key = piece_state.Key;
int piece_indx = BrunetDht.GetPieceIndexFromFragmentKey(piece_key);
global_state.Fragments[piece_indx] = dgr;
global_state.OpSuccCount++;
if ((global_state.Concurrency > 1 && global_state.OpSuccCount %
global_state.Concurrency == 0) || global_state.OpSuccCount ==
global_state.ExpectedPositiveReturnNum)
{
// put concurrently and a batch finishes.
global_state.BatchFinishedEvent.Set();
}
if (global_state.OpSuccCount == global_state.ExpectedPositiveReturnNum)
{
Logger.WriteLineIf(LogLevel.Verbose, _log_props,
string.Format("All pieces of {0} successfully got. Firing GetStoppedEvent",
Encoding.UTF8.GetString(global_state.BaseKey)));
global_state.Returns.Enqueue(new GetFragsStoppedEventArgs(global_state.Fragments));
}
}
}
else
{
Logger.WriteLineIf(LogLevel.Verbose, _log_props,
string.Format("Get failed for piece: {0}. Firing GetStoppedEvent",
Encoding.UTF8.GetString(piece_state.Key)));
//No retry at this level currently, stop put operation.
lock (global_state.SyncRoot) {
global_state.Returns.Enqueue(new PutFragsStoppedEventArgs(piece_state));
}
}
}
/// <summary>
/// Concurrenly gets the fragments from DHT.
/// </summary>
/// <returns>The fragments</returns>
private MemBlock GetFragsConcurrently(byte[] baseKey, int pieceNum,
out int largestAge, out int smallestTtl)
{
// First set the int values to be invalid.
smallestTtl = Int32.MaxValue;
largestAge = 0;
int max_enqueues = 1;
BlockingQueue bq_result = new BlockingQueue(max_enqueues);
AsyncGetFragsGlobalState global_state =
new AsyncGetFragsGlobalState(pieceNum, baseKey, bq_result);
int concurrency_degree = Concurrency;
global_state.Concurrency = concurrency_degree;
for (int i = 0; i < pieceNum; i++)
{
int index = i;
byte[] piece_key = BuildFragmentKey(baseKey, i);
string piece_key_string = Encoding.UTF8.GetString(piece_key);
// piece state
AsyncOpState aps = new AsyncOpState(piece_key);
AsyncFragsOpState afos = new AsyncFragsOpState(global_state, aps);
// async get, one instance of IDht per get because thread safty not guaranteed
IDht proxy = DhtServiceClient.GetXmlRpcDhtClient(_svc_uri.Port);
BrunetDhtClientOperations brdht_ops = new BrunetDhtClientOperations(
proxy);
lock (global_state.SyncRoot) {
brdht_ops.BeginGetWithCallback(piece_key,
new AsyncCallback(this.OnDhtGetReturns), afos);
}
Logger.WriteLineIf(LogLevel.Verbose, _log_props,
string.Format("Get piece {0} from DHT began (asynchronously)",
piece_key_string));
if ((concurrency_degree > 1 && (index + 1) % concurrency_degree == 0) ||
index == pieceNum - 1)
{
// Stop to wait for batch finish or all finish
global_state.BatchFinishedEvent.WaitOne();
if (concurrency_degree > 1)
{
Logger.WriteLineIf(LogLevel.Verbose, _log_props,
string.Format("Batch {0} finished. Moving on",
(int)((index + 1) / concurrency_degree)));
}
}
}
//block here until result comes
GetFragsStoppedEventArgs stop_args =
(GetFragsStoppedEventArgs)bq_result.Dequeue();
//All results have returned.
MemBlock ret = new MemBlock();
if (stop_args.IsSuccessful)
{
// We successfully got everything but aren't sure whether they are
// correct. Now parse them.
for (int i = 0; i < global_state.Fragments.Length; i++)
{
try {
DhtGetResult dgr = global_state.Fragments[i];
FingerprintedData fpd =
(FingerprintedData)DictionaryData.CreateDictionaryData(dgr.value);
RegularData rd = fpd.InnerData as RegularData;
// This piece is OK.
ret = MemBlock.Concat(ret, MemBlock.Reference(rd.PayLoad));
if (smallestTtl > dgr.ttl)
{
smallestTtl = dgr.ttl;
}
if (largestAge < dgr.age)
{
largestAge = dgr.age;
}
//Now it's safe to say, this attempt succeeded.
} catch (Exception) {
Logger.WriteLineIf(LogLevel.Error, _log_props,
string.Format("Parsing Piece failed at index {0}", i));
throw;
}
}
return(ret);
}
return(null);
}
/// <summary>
/// Concurrenly gets the fragments from DHT.
/// </summary>
/// <returns>The fragments</returns>
private MemBlock GetFragsConcurrently(byte[] baseKey, int pieceNum,
out int largestAge, out int smallestTtl)
{
// First set the int values to be invalid.
smallestTtl = Int32.MaxValue;
largestAge = 0;
int max_enqueues = 1;
BlockingQueue bq_result = new BlockingQueue(max_enqueues);
AsyncGetFragsGlobalState global_state =
new AsyncGetFragsGlobalState(pieceNum, baseKey, bq_result);
int concurrency_degree = Concurrency;
global_state.Concurrency = concurrency_degree;
for (int i = 0; i < pieceNum; i++) {
int index = i;
byte[] piece_key = BuildFragmentKey(baseKey, i);
string piece_key_string = Encoding.UTF8.GetString(piece_key);
// piece state
AsyncOpState aps = new AsyncOpState(piece_key);
AsyncFragsOpState afos = new AsyncFragsOpState(global_state, aps);
// async get, one instance of IDht per get because thread safty not guaranteed
IDht proxy = DhtServiceClient.GetXmlRpcDhtClient(_svc_uri.Port);
BrunetDhtClientOperations brdht_ops = new BrunetDhtClientOperations(
proxy);
lock (global_state.SyncRoot) {
brdht_ops.BeginGetWithCallback(piece_key,
new AsyncCallback(this.OnDhtGetReturns), afos);
}
Logger.WriteLineIf(LogLevel.Verbose, _log_props,
string.Format("Get piece {0} from DHT began (asynchronously)",
piece_key_string));
if ((concurrency_degree > 1 && (index + 1) % concurrency_degree == 0) ||
index == pieceNum - 1) {
// Stop to wait for batch finish or all finish
global_state.BatchFinishedEvent.WaitOne();
if (concurrency_degree > 1) {
Logger.WriteLineIf(LogLevel.Verbose, _log_props,
string.Format("Batch {0} finished. Moving on",
(int)((index + 1) / concurrency_degree)));
}
}
}
//block here until result comes
GetFragsStoppedEventArgs stop_args =
(GetFragsStoppedEventArgs)bq_result.Dequeue();
//All results have returned.
MemBlock ret = new MemBlock();
if (stop_args.IsSuccessful) {
// We successfully got everything but aren't sure whether they are
// correct. Now parse them.
for (int i = 0; i < global_state.Fragments.Length; i++) {
try {
DhtGetResult dgr = global_state.Fragments[i];
FingerprintedData fpd =
(FingerprintedData)DictionaryData.CreateDictionaryData(dgr.value);
RegularData rd = fpd.InnerData as RegularData;
// This piece is OK.
ret = MemBlock.Concat(ret, MemBlock.Reference(rd.PayLoad));
if (smallestTtl > dgr.ttl)
smallestTtl = dgr.ttl;
if (largestAge < dgr.age)
largestAge = dgr.age;
//Now it's safe to say, this attempt succeeded.
} catch (Exception) {
Logger.WriteLineIf(LogLevel.Error, _log_props,
string.Format("Parsing Piece failed at index {0}", i));
throw;
}
}
return ret;
}
return null;
}
