From e645fc2693acc796304498909786b7b47005b429 Mon Sep 17 00:00:00 2001 From: Martin Lucina Date: Mon, 23 Jan 2012 08:53:35 +0100 Subject: Imported Upstream version 2.1.3 --- src/xsub.cpp | 172 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 172 insertions(+) create mode 100644 src/xsub.cpp (limited to 'src/xsub.cpp') diff --git a/src/xsub.cpp b/src/xsub.cpp new file mode 100644 index 0000000..8c77925 --- /dev/null +++ b/src/xsub.cpp @@ -0,0 +1,172 @@ +/* + 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 . +*/ + +#include + +#include "../include/zmq.h" + +#include "xsub.hpp" +#include "err.hpp" + +zmq::xsub_t::xsub_t (class ctx_t *parent_, uint32_t tid_) : + socket_base_t (parent_, tid_), + fq (this), + has_message (false), + more (false) +{ + options.type = ZMQ_XSUB; + options.requires_in = true; + options.requires_out = false; + zmq_msg_init (&message); +} + +zmq::xsub_t::~xsub_t () +{ + zmq_msg_close (&message); +} + +void zmq::xsub_t::xattach_pipes (class reader_t *inpipe_, + class writer_t *outpipe_, const blob_t &peer_identity_) +{ + zmq_assert (inpipe_ && !outpipe_); + fq.attach (inpipe_); +} + +void zmq::xsub_t::process_term (int linger_) +{ + fq.terminate (); + socket_base_t::process_term (linger_); +} + +int zmq::xsub_t::xsend (zmq_msg_t *msg_, int options_) +{ + size_t size = zmq_msg_size (msg_); + unsigned char *data = (unsigned char*) zmq_msg_data (msg_); + + // Malformed subscriptions are dropped silently. + if (size >= 1) { + + // Process a subscription. + if (*data == 1) + subscriptions.add (data + 1, size - 1); + + // Process an unsubscription. Invalid unsubscription is ignored. + if (*data == 0) + subscriptions.rm (data + 1, size - 1); + } + + int rc = zmq_msg_close (msg_); + zmq_assert (rc == 0); + rc = zmq_msg_init (msg_); + zmq_assert (rc == 0); + return 0; +} + +bool zmq::xsub_t::xhas_out () +{ + // Subscription can be added/removed anytime. + return true; +} + +int zmq::xsub_t::xrecv (zmq_msg_t *msg_, int flags_) +{ + // If there's already a message prepared by a previous call to zmq_poll, + // return it straight ahead. + if (has_message) { + zmq_msg_move (msg_, &message); + has_message = false; + more = msg_->flags & ZMQ_MSG_MORE; + return 0; + } + + // TODO: This can result in infinite loop in the case of continuous + // stream of non-matching messages which breaks the non-blocking recv + // semantics. + while (true) { + + // Get a message using fair queueing algorithm. + int rc = fq.recv (msg_, flags_); + + // If there's no message available, return immediately. + // The same when error occurs. + if (rc != 0) + return -1; + + // Check whether the message matches at least one subscription. + // Non-initial parts of the message are passed + if (more || match (msg_)) { + more = msg_->flags & ZMQ_MSG_MORE; + return 0; + } + + // Message doesn't match. Pop any remaining parts of the message + // from the pipe. + while (msg_->flags & ZMQ_MSG_MORE) { + rc = fq.recv (msg_, ZMQ_NOBLOCK); + zmq_assert (rc == 0); + } + } +} + +bool zmq::xsub_t::xhas_in () +{ + // There are subsequent parts of the partly-read message available. + if (more) + return true; + + // If there's already a message prepared by a previous call to zmq_poll, + // return straight ahead. + if (has_message) + return true; + + // TODO: This can result in infinite loop in the case of continuous + // stream of non-matching messages. + while (true) { + + // Get a message using fair queueing algorithm. + int rc = fq.recv (&message, ZMQ_NOBLOCK); + + // If there's no message available, return immediately. + // The same when error occurs. + if (rc != 0) { + zmq_assert (errno == EAGAIN); + return false; + } + + // Check whether the message matches at least one subscription. + if (match (&message)) { + has_message = true; + return true; + } + + // Message doesn't match. Pop any remaining parts of the message + // from the pipe. + while (message.flags & ZMQ_MSG_MORE) { + rc = fq.recv (&message, ZMQ_NOBLOCK); + zmq_assert (rc == 0); + } + } +} + +bool zmq::xsub_t::match (zmq_msg_t *msg_) +{ + return subscriptions.check ((unsigned char*) zmq_msg_data (msg_), + zmq_msg_size (msg_)); +} -- cgit v1.2.3