From a15854bd92db69fcd0b4444fe1b8fe3610a7acf6 Mon Sep 17 00:00:00 2001 From: Martin Lucina Date: Mon, 23 Jan 2012 08:53:19 +0100 Subject: Imported Upstream version 2.0.7.dfsg --- src/fq.cpp | 130 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 130 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..9028853 --- /dev/null +++ b/src/fq.cpp @@ -0,0 +1,130 @@ +/* + Copyright (c) 2007-2010 iMatix Corporation + + This file is part of 0MQ. + + 0MQ is free software; you can redistribute it and/or modify it under + the terms of the Lesser GNU 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 + Lesser GNU General Public License for more details. + + You should have received a copy of the Lesser GNU General Public License + along with this program. If not, see . +*/ + +#include "../include/zmq.h" + +#include "fq.hpp" +#include "pipe.hpp" +#include "err.hpp" + +zmq::fq_t::fq_t () : + active (0), + current (0), + more (false) +{ +} + +zmq::fq_t::~fq_t () +{ + for (pipes_t::size_type i = 0; i != pipes.size (); i++) + pipes [i]->term (); +} + +void zmq::fq_t::attach (reader_t *pipe_) +{ + pipes.push_back (pipe_); + pipes.swap (active, pipes.size () - 1); + active++; +} + +void zmq::fq_t::detach (reader_t *pipe_) +{ + zmq_assert (!more || pipes [current] != pipe_); + + // Remove the pipe from the list; adjust number of active pipes + // accordingly. + if (pipes.index (pipe_) < active) { + active--; + if (current == active) + current = 0; + } + pipes.erase (pipe_); +} + +void zmq::fq_t::kill (reader_t *pipe_) +{ + // Move the pipe to the list of inactive pipes. + active--; + if (current == active) + current = 0; + pipes.swap (pipes.index (pipe_), active); +} + +void zmq::fq_t::revive (reader_t *pipe_) +{ + // Move the pipe to the list of active pipes. + pipes.swap (pipes.index (pipe_), active); + active++; +} + +int zmq::fq_t::recv (zmq_msg_t *msg_, int flags_) +{ + // Deallocate old content of the message. + zmq_msg_close (msg_); + + // Round-robin over the pipes to get the next message. + for (int count = active; count != 0; count--) { + + // 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_); + zmq_assert (!(more && !fetched)); + + // Note that when message is not fetched, current pipe is killed and + // replaced by another active pipe. Thus we don't have to increase + // the 'current' pointer. + if (fetched) { + more = msg_->flags & ZMQ_MSG_MORE; + if (!more) { + current++; + if (current >= active) + current = 0; + } + return 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::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. + for (int count = active; count != 0; count--) { + if (pipes [current]->check_read ()) + return true; + current++; + if (current >= active) + current = 0; + } + + return false; +} + -- cgit v1.2.3