From ad6fa9d0d4f1cf29ce63998d7efe337b1a784ef6 Mon Sep 17 00:00:00 2001 From: Martin Sustrik Date: Tue, 27 Apr 2010 17:36:00 +0200 Subject: initial version of multi-hop REQ/REP --- src/xrep.cpp | 195 +++++++++++++++++++++++++++++++++++++++++++++++------------ 1 file changed, 158 insertions(+), 37 deletions(-) (limited to 'src/xrep.cpp') diff --git a/src/xrep.cpp b/src/xrep.cpp index c70c3ac..051a5ce 100644 --- a/src/xrep.cpp +++ b/src/xrep.cpp @@ -24,7 +24,11 @@ #include "pipe.hpp" zmq::xrep_t::xrep_t (class app_thread_t *parent_) : - socket_base_t (parent_) + socket_base_t (parent_), + current_in (0), + more_in (false), + current_out (NULL), + more_out (false) { options.requires_in = true; options.requires_out = true; @@ -32,56 +36,96 @@ zmq::xrep_t::xrep_t (class app_thread_t *parent_) : // On connect, pipes are created only after initial handshaking. // That way we are aware of the peer's identity when binding to the pipes. options.immediate_connect = false; - - // XREP is unfunctional at the moment. Crash here! - zmq_assert (false); } zmq::xrep_t::~xrep_t () { + for (inpipes_t::iterator it = inpipes.begin (); it != inpipes.end (); it++) + it->reader->term (); + for (outpipes_t::iterator it = outpipes.begin (); it != outpipes.end (); + it++) + it->second.writer->term (); } void zmq::xrep_t::xattach_pipes (class reader_t *inpipe_, class writer_t *outpipe_, const blob_t &peer_identity_) { zmq_assert (inpipe_ && outpipe_); - fq.attach (inpipe_); // TODO: What if new connection has same peer identity as the old one? + outpipe_t outpipe = {outpipe_, true}; bool ok = outpipes.insert (std::make_pair ( - peer_identity_, outpipe_)).second; + peer_identity_, outpipe)).second; zmq_assert (ok); + + inpipe_t inpipe = {inpipe_, peer_identity_, true}; + inpipes.push_back (inpipe); } void zmq::xrep_t::xdetach_inpipe (class reader_t *pipe_) { - zmq_assert (pipe_); - fq.detach (pipe_); +// TODO:! + for (inpipes_t::iterator it = inpipes.begin (); it != inpipes.end (); + it++) { + if (it->reader == pipe_) { + inpipes.erase (it); + return; + } + } + zmq_assert (false); } void zmq::xrep_t::xdetach_outpipe (class writer_t *pipe_) { for (outpipes_t::iterator it = outpipes.begin (); - it != outpipes.end (); ++it) - if (it->second == pipe_) { + it != outpipes.end (); ++it) { + if (it->second.writer == pipe_) { outpipes.erase (it); + if (pipe_ == current_out) + current_out = NULL; return; } + } zmq_assert (false); } void zmq::xrep_t::xkill (class reader_t *pipe_) { - fq.kill (pipe_); + for (inpipes_t::iterator it = inpipes.begin (); it != inpipes.end (); + it++) { + if (it->reader == pipe_) { + zmq_assert (it->active); + it->active = false; + return; + } + } + zmq_assert (false); } void zmq::xrep_t::xrevive (class reader_t *pipe_) { - fq.revive (pipe_); + for (inpipes_t::iterator it = inpipes.begin (); it != inpipes.end (); + it++) { + if (it->reader == pipe_) { + zmq_assert (!it->active); + it->active = true; + return; + } + } + zmq_assert (false); } void zmq::xrep_t::xrevive (class writer_t *pipe_) { + for (outpipes_t::iterator it = outpipes.begin (); + it != outpipes.end (); ++it) { + if (it->second.writer == pipe_) { + zmq_assert (!it->second.active); + it->second.active = true; + return; + } + } + zmq_assert (false); } int zmq::xrep_t::xsetsockopt (int option_, const void *optval_, @@ -93,33 +137,45 @@ int zmq::xrep_t::xsetsockopt (int option_, const void *optval_, int zmq::xrep_t::xsend (zmq_msg_t *msg_, int flags_) { - unsigned char *data = (unsigned char*) zmq_msg_data (msg_); - size_t size = zmq_msg_size (msg_); - - // Check whether the message is well-formed. - zmq_assert (size >= 1); - zmq_assert (size_t (*data + 1) <= size); - - // Find the corresponding outbound pipe. If there's none, just drop the - // message. - // TODO: There's an allocation here! It's the critical path! Get rid of it! - blob_t identity (data + 1, *data); - outpipes_t::iterator it = outpipes.find (identity); - if (it == outpipes.end ()) { - int rc = zmq_msg_close (msg_); - zmq_assert (rc == 0); - rc = zmq_msg_init (msg_); - zmq_assert (rc == 0); + // If this is the first part of the message it's the identity of the + // peer to send the message to. + if (!more_out) { + zmq_assert (!current_out); + + // There's no such thing as prefix with no subsequent message. + zmq_assert (msg_->flags & ZMQ_MSG_MORE); + more_out = true; + + // Find the pipe associated with the identity stored in the prefix. + // If there's no such pipe just silently drop the message. + blob_t identity ((unsigned char*) zmq_msg_data (msg_), + zmq_msg_size (msg_)); + outpipes_t::iterator it = outpipes.find (identity); + if (it == outpipes.end ()) + return 0; + + // Remember the outgoing pipe. + current_out = it->second.writer; + return 0; } - // Push message to the selected pipe. - if (!it->second->write (msg_)) { - errno = EAGAIN; - return -1; - } + // Check whether this is the last part of the message. + more_out = msg_->flags & ZMQ_MSG_MORE; - it->second->flush (); + // Push the message into the pipe. If there's no out pipe, just drop it. + if (current_out) { + bool ok = current_out->write (msg_); + zmq_assert (ok); + if (!more_out) { + current_out->flush (); + current_out = NULL; + } + } + else { + int rc = zmq_msg_close (msg_); + zmq_assert (rc == 0); + } // Detach the message from the data buffer. int rc = zmq_msg_init (msg_); @@ -130,12 +186,77 @@ int zmq::xrep_t::xsend (zmq_msg_t *msg_, int flags_) int zmq::xrep_t::xrecv (zmq_msg_t *msg_, int flags_) { - return fq.recv (msg_, flags_); + // Deallocate old content of the message. + zmq_msg_close (msg_); + + // If we are in the middle of reading a message, just grab next part of it. + if (more_in) { + zmq_assert (inpipes [current_in].active); + bool fetched = inpipes [current_in].reader->read (msg_); + zmq_assert (fetched); + more_in = msg_->flags & ZMQ_MSG_MORE; + if (!more_in) { + current_in++; + if (current_in >= inpipes.size ()) + current_in = 0; + } + return 0; + } + + // Round-robin over the pipes to get the next message. + for (int count = inpipes.size (); count != 0; count--) { + + // Try to fetch new message. + bool fetched; + if (!inpipes [current_in].active) + fetched = false; + else + fetched = inpipes [current_in].reader->check_read (); + + // If we have a message, create a prefix and return it to the caller. + if (fetched) { + int rc = zmq_msg_init_size (msg_, + inpipes [current_in].identity.size ()); + zmq_assert (rc == 0); + memcpy (zmq_msg_data (msg_), inpipes [current_in].identity.data (), + zmq_msg_size (msg_)); + more_in = true; + return 0; + } + + // If me don't have a message, move to next pipe. + current_in++; + if (current_in >= inpipes.size ()) + current_in = 0; + } + + // No message is available. Initialise the output parameter + // to be a 0-byte message. + zmq_msg_init (msg_); + errno = EAGAIN; + return -1; } bool zmq::xrep_t::xhas_in () { - return fq.has_in (); + // There are subsequent parts of the partly-read message available. + if (more_in) + return true; + + // Note that messing with current doesn't break the fairness of fair + // queueing algorithm. If there are no messages available current will + // get back to its original value. Otherwise it'll point to the first + // pipe holding messages, skipping only pipes with no messages available. + for (int count = inpipes.size (); count != 0; count--) { + if (inpipes [current_in].active && + inpipes [current_in].reader->check_read ()) + return true; + current_in++; + if (current_in >= inpipes.size ()) + current_in = 0; + } + + return false; } bool zmq::xrep_t::xhas_out () -- cgit v1.2.3