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Diffstat (limited to 'src/dist.cpp')
| -rw-r--r-- | src/dist.cpp | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/src/dist.cpp b/src/dist.cpp new file mode 100644 index 0000000..e447bc1 --- /dev/null +++ b/src/dist.cpp @@ -0,0 +1,196 @@ +/* + Copyright (c) 2007-2011 iMatix Corporation + 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 "../include/zmq.h" + +#include "dist.hpp" +#include "pipe.hpp" +#include "err.hpp" +#include "own.hpp" +#include "msg_content.hpp" + +zmq::dist_t::dist_t (own_t *sink_) : + active (0), + more (false), + sink (sink_), + terminating (false) +{ +} + +zmq::dist_t::~dist_t () +{ + zmq_assert (pipes.empty ()); +} + +void zmq::dist_t::attach (writer_t *pipe_) +{ + // If we are in the middle of sending a message, let's postpone plugging + // in the pipe. + if (!terminating && more) { + new_pipes.push_back (pipe_); + return; + } + + pipe_->set_event_sink (this); + + pipes.push_back (pipe_); + pipes.swap (active, pipes.size () - 1); + active++; + + if (terminating) { + sink->register_term_acks (1); + pipe_->terminate (); + } +} + +void zmq::dist_t::terminate () +{ + zmq_assert (!terminating); + terminating = true; + + sink->register_term_acks (pipes.size ()); + for (pipes_t::size_type i = 0; i != pipes.size (); i++) + pipes [i]->terminate (); +} + +void zmq::dist_t::terminated (writer_t *pipe_) +{ + // Remove the pipe from the list; adjust number of active pipes + // accordingly. + if (pipes.index (pipe_) < active) + active--; + pipes.erase (pipe_); + + if (terminating) + sink->unregister_term_ack (); +} + +void zmq::dist_t::activated (writer_t *pipe_) +{ + // Move the pipe to the list of active pipes. + pipes.swap (pipes.index (pipe_), active); + active++; +} + +int zmq::dist_t::send (zmq_msg_t *msg_, int flags_) +{ + // Is this end of a multipart message? + bool msg_more = msg_->flags & ZMQ_MSG_MORE; + + // Push the message to active pipes. + distribute (msg_, flags_); + + // If mutlipart message is fully sent, activate new pipes. + if (more && !msg_more) + clear_new_pipes (); + + more = msg_more; + + return 0; +} + +void zmq::dist_t::distribute (zmq_msg_t *msg_, int flags_) +{ + // If there are no active pipes available, simply drop the message. + if (active == 0) { + int rc = zmq_msg_close (msg_); + zmq_assert (rc == 0); + rc = zmq_msg_init (msg_); + zmq_assert (rc == 0); + return; + } + + msg_content_t *content = (msg_content_t*) msg_->content; + + // For VSMs the copying is straighforward. + if (content == (msg_content_t*) ZMQ_VSM) { + for (pipes_t::size_type i = 0; i < active;) + if (write (pipes [i], msg_)) + i++; + int rc = zmq_msg_init (msg_); + zmq_assert (rc == 0); + return; + } + + // Optimisation for the case when there's only a single pipe + // to send the message to - no refcount adjustment i.e. no atomic + // operations are needed. + if (active == 1) { + if (!write (pipes [0], msg_)) { + int rc = zmq_msg_close (msg_); + zmq_assert (rc == 0); + } + int rc = zmq_msg_init (msg_); + zmq_assert (rc == 0); + return; + } + + // There are at least 2 destinations for the message. That means we have + // to deal with reference counting. First add N-1 references to + // the content (we are holding one reference anyway, that's why -1). + if (msg_->flags & ZMQ_MSG_SHARED) + content->refcnt.add (active - 1); + else { + content->refcnt.set (active); + msg_->flags |= ZMQ_MSG_SHARED; + } + + // Push the message to all destinations. + for (pipes_t::size_type i = 0; i < active;) { + if (!write (pipes [i], msg_)) + content->refcnt.sub (1); + else + i++; + } + + // Detach the original message from the data buffer. + int rc = zmq_msg_init (msg_); + zmq_assert (rc == 0); +} + +bool zmq::dist_t::has_out () +{ + return true; +} + +bool zmq::dist_t::write (class writer_t *pipe_, zmq_msg_t *msg_) +{ + if (!pipe_->write (msg_)) { + active--; + pipes.swap (pipes.index (pipe_), active); + return false; + } + if (!(msg_->flags & ZMQ_MSG_MORE)) + pipe_->flush (); + return true; +} + +void zmq::dist_t::clear_new_pipes () +{ + for (new_pipes_t::iterator it = new_pipes.begin (); it != new_pipes.end (); + ++it) { + (*it)->set_event_sink (this); + pipes.push_back (*it); + pipes.swap (active, pipes.size () - 1); + active++; + } + new_pipes.clear (); +} + |