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Diffstat (limited to 'src/router.cpp')
| -rw-r--r-- | src/router.cpp | 364 |
1 files changed, 364 insertions, 0 deletions
diff --git a/src/router.cpp b/src/router.cpp new file mode 100644 index 0000000..c136e60 --- /dev/null +++ b/src/router.cpp @@ -0,0 +1,364 @@ +/* + Copyright (c) 2012 iMatix Corporation + Copyright (c) 2009-2011 250bpm s.r.o. + Copyright (c) 2011 VMware, Inc. + Copyright (c) 2007-2011 Other contributors as noted in the AUTHORS file + + This file is part of 0MQ. + + 0MQ is free software; you can redistribute it and/or modify it under + the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + 0MQ is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ + +#include "router.hpp" +#include "pipe.hpp" +#include "wire.hpp" +#include "random.hpp" +#include "likely.hpp" +#include "err.hpp" + +zmq::router_t::router_t (class ctx_t *parent_, uint32_t tid_, int sid_) : + socket_base_t (parent_, tid_, sid_), + prefetched (false), + identity_sent (false), + more_in (false), + current_out (NULL), + more_out (false), + next_peer_id (generate_random ()), + mandatory(false) +{ + options.type = ZMQ_ROUTER; + + // TODO: Uncomment the following line when ROUTER will become true ROUTER + // rather than generic router socket. + // If peer disconnect there's noone to send reply to anyway. We can drop + // all the outstanding requests from that peer. + // options.delay_on_disconnect = false; + + options.recv_identity = true; + + prefetched_id.init (); + prefetched_msg.init (); +} + +zmq::router_t::~router_t () +{ + zmq_assert (anonymous_pipes.empty ());; + zmq_assert (outpipes.empty ()); + prefetched_id.close (); + prefetched_msg.close (); +} + +void zmq::router_t::xattach_pipe (pipe_t *pipe_, bool icanhasall_) +{ + // icanhasall_ is unused + (void)icanhasall_; + + zmq_assert (pipe_); + + bool identity_ok = identify_peer (pipe_); + if (identity_ok) + fq.attach (pipe_); + else + anonymous_pipes.insert (pipe_); +} + +int zmq::router_t::xsetsockopt (int option_, const void *optval_, + size_t optvallen_) +{ + if (option_ != ZMQ_ROUTER_MANDATORY) { + errno = EINVAL; + return -1; + } + if (optvallen_ != sizeof (int) || *static_cast <const int*> (optval_) < 0) { + errno = EINVAL; + return -1; + } + mandatory = *static_cast <const int*> (optval_); + return 0; +} + +void zmq::router_t::xterminated (pipe_t *pipe_) +{ + std::set <pipe_t*>::iterator it = anonymous_pipes.find (pipe_); + if (it != anonymous_pipes.end ()) + anonymous_pipes.erase (it); + else { + outpipes_t::iterator it = outpipes.find (pipe_->get_identity ()); + zmq_assert (it != outpipes.end ()); + outpipes.erase (it); + fq.terminated (pipe_); + if (pipe_ == current_out) + current_out = NULL; + } +} + +void zmq::router_t::xread_activated (pipe_t *pipe_) +{ + std::set <pipe_t*>::iterator it = anonymous_pipes.find (pipe_); + if (it == anonymous_pipes.end ()) + fq.activated (pipe_); + else { + bool identity_ok = identify_peer (pipe_); + if (identity_ok) { + anonymous_pipes.erase (it); + fq.attach (pipe_); + } + } +} + +void zmq::router_t::xwrite_activated (pipe_t *pipe_) +{ + outpipes_t::iterator it; + for (it = outpipes.begin (); it != outpipes.end (); ++it) + if (it->second.pipe == pipe_) + break; + + zmq_assert (it != outpipes.end ()); + zmq_assert (!it->second.active); + it->second.active = true; +} + +int zmq::router_t::xsend (msg_t *msg_, int flags_) +{ + // flags_ is unused + (void)flags_; + + // If this is the first part of the message it's the ID of the + // peer to send the message to. + if (!more_out) { + zmq_assert (!current_out); + + // If we have malformed message (prefix with no subsequent message) + // then just silently ignore it. + // TODO: The connections should be killed instead. + if (msg_->flags () & msg_t::more) { + + more_out = true; + + // Find the pipe associated with the identity stored in the prefix. + // If there's no such pipe just silently ignore the message, unless + // report_unreachable is set. + blob_t identity ((unsigned char*) msg_->data (), msg_->size ()); + outpipes_t::iterator it = outpipes.find (identity); + + if (it != outpipes.end ()) { + current_out = it->second.pipe; + if (!current_out->check_write ()) { + it->second.active = false; + current_out = NULL; + } + } + else + if (mandatory) { + more_out = false; + errno = EHOSTUNREACH; + return -1; + } + } + + int rc = msg_->close (); + errno_assert (rc == 0); + rc = msg_->init (); + errno_assert (rc == 0); + return 0; + } + + // Check whether this is the last part of the message. + more_out = msg_->flags () & msg_t::more ? true : false; + + // Push the message into the pipe. If there's no out pipe, just drop it. + if (current_out) { + bool ok = current_out->write (msg_); + if (unlikely (!ok)) + current_out = NULL; + else if (!more_out) { + current_out->flush (); + current_out = NULL; + } + } + else { + int rc = msg_->close (); + errno_assert (rc == 0); + } + + // Detach the message from the data buffer. + int rc = msg_->init (); + errno_assert (rc == 0); + + return 0; +} + +int zmq::router_t::xrecv (msg_t *msg_, int flags_) +{ + // flags_ is unused + (void)flags_; + + if (prefetched) { + if (!identity_sent) { + int rc = msg_->move (prefetched_id); + errno_assert (rc == 0); + identity_sent = true; + } + else { + int rc = msg_->move (prefetched_msg); + errno_assert (rc == 0); + prefetched = false; + } + more_in = msg_->flags () & msg_t::more ? true : false; + return 0; + } + + pipe_t *pipe = NULL; + int rc = fq.recvpipe (msg_, &pipe); + + // It's possible that we receive peer's identity. That happens + // after reconnection. The current implementation assumes that + // the peer always uses the same identity. + // TODO: handle the situation when the peer changes its identity. + while (rc == 0 && msg_->is_identity ()) + rc = fq.recvpipe (msg_, &pipe); + + if (rc != 0) + return -1; + + zmq_assert (pipe != NULL); + + // If we are in the middle of reading a message, just return the next part. + if (more_in) + more_in = msg_->flags () & msg_t::more ? true : false; + else { + // We are at the beginning of a message. + // Keep the message part we have in the prefetch buffer + // and return the ID of the peer instead. + rc = prefetched_msg.move (*msg_); + errno_assert (rc == 0); + prefetched = true; + + blob_t identity = pipe->get_identity (); + rc = msg_->init_size (identity.size ()); + errno_assert (rc == 0); + memcpy (msg_->data (), identity.data (), identity.size ()); + msg_->set_flags (msg_t::more); + identity_sent = true; + } + + return 0; +} + +int zmq::router_t::rollback (void) +{ + if (current_out) { + current_out->rollback (); + current_out = NULL; + more_out = false; + } + return 0; +} + +bool zmq::router_t::xhas_in () +{ + // If we are in the middle of reading the messages, there are + // definitely more parts available. + if (more_in) + return true; + + // We may already have a message pre-fetched. + if (prefetched) + return true; + + // Try to read the next message. + // The message, if read, is kept in the pre-fetch buffer. + pipe_t *pipe = NULL; + int rc = fq.recvpipe (&prefetched_msg, &pipe); + + // It's possible that we receive peer's identity. That happens + // after reconnection. The current implementation assumes that + // the peer always uses the same identity. + // TODO: handle the situation when the peer changes its identity. + while (rc == 0 && prefetched_msg.is_identity ()) + rc = fq.recvpipe (&prefetched_msg, &pipe); + + if (rc != 0) + return false; + + zmq_assert (pipe != NULL); + + blob_t identity = pipe->get_identity (); + rc = prefetched_id.init_size (identity.size ()); + errno_assert (rc == 0); + memcpy (prefetched_id.data (), identity.data (), identity.size ()); + prefetched_id.set_flags (msg_t::more); + + prefetched = true; + identity_sent = false; + + return true; +} + +bool zmq::router_t::xhas_out () +{ + // In theory, ROUTER socket is always ready for writing. Whether actual + // attempt to write succeeds depends on whitch pipe the message is going + // to be routed to. + return true; +} + +bool zmq::router_t::identify_peer (pipe_t *pipe_) +{ + msg_t msg; + blob_t identity; + + msg.init (); + bool ok = pipe_->read (&msg); + if (!ok) + return false; + + if (msg.size () == 0) { + // Fall back on the auto-generation + unsigned char buf [5]; + buf [0] = 0; + put_uint32 (buf + 1, next_peer_id++); + identity = blob_t (buf, sizeof buf); + msg.close (); + } + else { + identity = blob_t ((unsigned char*) msg.data (), msg.size ()); + outpipes_t::iterator it = outpipes.find (identity); + msg.close (); + + // Ignore peers with duplicate ID. + if (it != outpipes.end ()) + return false; + } + + pipe_->set_identity (identity); + // Add the record into output pipes lookup table + outpipe_t outpipe = {pipe_, true}; + ok = outpipes.insert (outpipes_t::value_type (identity, outpipe)).second; + zmq_assert (ok); + + return true; +} + +zmq::router_session_t::router_session_t (io_thread_t *io_thread_, bool connect_, + socket_base_t *socket_, const options_t &options_, + const address_t *addr_) : + session_base_t (io_thread_, connect_, socket_, options_, addr_) +{ +} + +zmq::router_session_t::~router_session_t () +{ +} + |