From 597cc5edd624525563e6549dc0057eca2a51c81d Mon Sep 17 00:00:00 2001 From: Micah Anderson Date: Tue, 11 Nov 2014 13:30:46 -0500 Subject: upgrade to new version --- src/fq.cpp | 138 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 138 insertions(+) create mode 100644 src/fq.cpp (limited to 'src/fq.cpp') diff --git a/src/fq.cpp b/src/fq.cpp new file mode 100644 index 0000000..aa099eb --- /dev/null +++ b/src/fq.cpp @@ -0,0 +1,138 @@ +/* + Copyright (c) 2007-2013 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 . +*/ + +#include "fq.hpp" +#include "pipe.hpp" +#include "err.hpp" +#include "msg.hpp" + +zmq::fq_t::fq_t () : + active (0), + current (0), + more (false) +{ +} + +zmq::fq_t::~fq_t () +{ + zmq_assert (pipes.empty ()); +} + +void zmq::fq_t::attach (pipe_t *pipe_) +{ + pipes.push_back (pipe_); + pipes.swap (active, pipes.size () - 1); + active++; +} + +void zmq::fq_t::pipe_terminated (pipe_t *pipe_) +{ + const pipes_t::size_type index = pipes.index (pipe_); + + // Remove the pipe from the list; adjust number of active pipes + // accordingly. + if (index < active) { + active--; + pipes.swap (index, active); + if (current == active) + current = 0; + } + pipes.erase (pipe_); +} + +void zmq::fq_t::activated (pipe_t *pipe_) +{ + // Move the pipe to the list of active pipes. + pipes.swap (pipes.index (pipe_), active); + active++; +} + +int zmq::fq_t::recv (msg_t *msg_) +{ + return recvpipe (msg_, NULL); +} + +int zmq::fq_t::recvpipe (msg_t *msg_, pipe_t **pipe_) +{ + // Deallocate old content of the message. + int rc = msg_->close (); + errno_assert (rc == 0); + + // Round-robin over the pipes to get the next message. + while (active > 0) { + + // Try to fetch new message. If we've already read part of the message + // subsequent part should be immediately available. + bool fetched = pipes [current]->read (msg_); + + // Note that when message is not fetched, current pipe is deactivated + // and replaced by another active pipe. Thus we don't have to increase + // the 'current' pointer. + if (fetched) { + if (pipe_) + *pipe_ = pipes [current]; + more = msg_->flags () & msg_t::more? true: false; + if (!more) + current = (current + 1) % active; + return 0; + } + + // Check the atomicity of the message. + // If we've already received the first part of the message + // we should get the remaining parts without blocking. + zmq_assert (!more); + + active--; + pipes.swap (current, active); + if (current == active) + current = 0; + } + + // No message is available. Initialise the output parameter + // to be a 0-byte message. + rc = msg_->init (); + errno_assert (rc == 0); + errno = EAGAIN; + return -1; +} + +bool zmq::fq_t::has_in () +{ + // There are subsequent parts of the partly-read message available. + if (more) + 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. + while (active > 0) { + if (pipes [current]->check_read ()) + return true; + + // Deactivate the pipe. + active--; + pipes.swap (current, active); + if (current == active) + current = 0; + } + + return false; +} + -- cgit v1.2.3