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/lb.cpp | 123 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 123 insertions(+) create mode 100644 src/lb.cpp (limited to 'src/lb.cpp') diff --git a/src/lb.cpp b/src/lb.cpp new file mode 100644 index 0000000..ca93ba2 --- /dev/null +++ b/src/lb.cpp @@ -0,0 +1,123 @@ +/* + 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 "lb.hpp" +#include "pipe.hpp" +#include "err.hpp" + +zmq::lb_t::lb_t () : + active (0), + current (0), + more (false) +{ +} + +zmq::lb_t::~lb_t () +{ + for (pipes_t::size_type i = 0; i != pipes.size (); i++) + pipes [i]->term (); +} + +void zmq::lb_t::attach (writer_t *pipe_) +{ + pipes.push_back (pipe_); + pipes.swap (active, pipes.size () - 1); + active++; +} + +void zmq::lb_t::detach (writer_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::lb_t::revive (writer_t *pipe_) +{ + // Move the pipe to the list of active pipes. + pipes.swap (pipes.index (pipe_), active); + active++; +} + +int zmq::lb_t::send (zmq_msg_t *msg_, int flags_) +{ + while (active > 0) { + if (pipes [current]->write (msg_)) { + more = msg_->flags & ZMQ_MSG_MORE; + break; + } + + zmq_assert (!more); + active--; + if (current < active) + pipes.swap (current, active); + else + current = 0; + } + + // If there are no pipes we cannot send the message. + if (active == 0) { + errno = EAGAIN; + return -1; + } + + // If it's final part of the message we can fluch it downstream and + // continue round-robinning (load balance). + if (!more) { + pipes [current]->flush (); + current = (current + 1) % active; + } + + // Detach the message from the data buffer. + int rc = zmq_msg_init (msg_); + zmq_assert (rc == 0); + + return 0; +} + +bool zmq::lb_t::has_out () +{ + // If one part of the message was already written we can definitely + // write the rest of the message. + if (more) + return true; + + while (active > 0) { + if (pipes [current]->check_write ()) + return true; + + active--; + if (current < active) + pipes.swap (current, active); + else + current = 0; + } + + return false; +} + -- cgit v1.2.3