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Diffstat (limited to 'src/xrep.cpp')
-rw-r--r-- | src/xrep.cpp | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/src/xrep.cpp b/src/xrep.cpp new file mode 100644 index 0000000..4e8d18a --- /dev/null +++ b/src/xrep.cpp @@ -0,0 +1,271 @@ +/* + 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 <http://www.gnu.org/licenses/>. +*/ + +#include "../include/zmq.h" + +#include "xrep.hpp" +#include "err.hpp" +#include "pipe.hpp" + +zmq::xrep_t::xrep_t (class app_thread_t *parent_) : + socket_base_t (parent_), + current_in (0), + more_in (false), + current_out (NULL), + more_out (false) +{ + options.requires_in = true; + options.requires_out = true; + + // On connect, pipes are created only after initial handshaking. + // That way we are aware of the peer's identity when binding to the pipes. + options.immediate_connect = false; +} + +zmq::xrep_t::~xrep_t () +{ + for (inpipes_t::iterator it = inpipes.begin (); it != inpipes.end (); it++) + it->reader->term (); + for (outpipes_t::iterator it = outpipes.begin (); it != outpipes.end (); + it++) + it->second.writer->term (); +} + +void zmq::xrep_t::xattach_pipes (class reader_t *inpipe_, + class writer_t *outpipe_, const blob_t &peer_identity_) +{ + zmq_assert (inpipe_ && outpipe_); + + // TODO: What if new connection has same peer identity as the old one? + outpipe_t outpipe = {outpipe_, true}; + bool ok = outpipes.insert (std::make_pair ( + peer_identity_, outpipe)).second; + zmq_assert (ok); + + inpipe_t inpipe = {inpipe_, peer_identity_, true}; + inpipes.push_back (inpipe); +} + +void zmq::xrep_t::xdetach_inpipe (class reader_t *pipe_) +{ +// TODO:! + for (inpipes_t::iterator it = inpipes.begin (); it != inpipes.end (); + it++) { + if (it->reader == pipe_) { + inpipes.erase (it); + return; + } + } + zmq_assert (false); +} + +void zmq::xrep_t::xdetach_outpipe (class writer_t *pipe_) +{ + for (outpipes_t::iterator it = outpipes.begin (); + it != outpipes.end (); ++it) { + if (it->second.writer == pipe_) { + outpipes.erase (it); + if (pipe_ == current_out) + current_out = NULL; + return; + } + } + zmq_assert (false); +} + +void zmq::xrep_t::xkill (class reader_t *pipe_) +{ + for (inpipes_t::iterator it = inpipes.begin (); it != inpipes.end (); + it++) { + if (it->reader == pipe_) { + zmq_assert (it->active); + it->active = false; + return; + } + } + zmq_assert (false); +} + +void zmq::xrep_t::xrevive (class reader_t *pipe_) +{ + for (inpipes_t::iterator it = inpipes.begin (); it != inpipes.end (); + it++) { + if (it->reader == pipe_) { + zmq_assert (!it->active); + it->active = true; + return; + } + } + zmq_assert (false); +} + +void zmq::xrep_t::xrevive (class writer_t *pipe_) +{ + for (outpipes_t::iterator it = outpipes.begin (); + it != outpipes.end (); ++it) { + if (it->second.writer == pipe_) { + zmq_assert (!it->second.active); + it->second.active = true; + return; + } + } + zmq_assert (false); +} + +int zmq::xrep_t::xsetsockopt (int option_, const void *optval_, + size_t optvallen_) +{ + errno = EINVAL; + return -1; +} + +int zmq::xrep_t::xsend (zmq_msg_t *msg_, int flags_) +{ + // If this is the first part of the message it's the identity of the + // peer to send the message to. + if (!more_out) { + zmq_assert (!current_out); + + // There's no such thing as prefix with no subsequent message. + zmq_assert (msg_->flags & ZMQ_MSG_MORE); + more_out = true; + + // Find the pipe associated with the identity stored in the prefix. + // If there's no such pipe just silently drop the message. + blob_t identity ((unsigned char*) zmq_msg_data (msg_), + zmq_msg_size (msg_)); + outpipes_t::iterator it = outpipes.find (identity); + if (it == outpipes.end ()) + return 0; + + // Remember the outgoing pipe. + current_out = it->second.writer; + + return 0; + } + + // Check whether this is the last part of the message. + more_out = msg_->flags & ZMQ_MSG_MORE; + + // Push the message into the pipe. If there's no out pipe, just drop it. + if (current_out) { + bool ok = current_out->write (msg_); + zmq_assert (ok); + if (!more_out) { + current_out->flush (); + current_out = NULL; + } + } + else { + int rc = zmq_msg_close (msg_); + zmq_assert (rc == 0); + } + + // Detach the message from the data buffer. + int rc = zmq_msg_init (msg_); + zmq_assert (rc == 0); + + return 0; +} + +int zmq::xrep_t::xrecv (zmq_msg_t *msg_, int flags_) +{ + // Deallocate old content of the message. + zmq_msg_close (msg_); + + // If we are in the middle of reading a message, just grab next part of it. + if (more_in) { + zmq_assert (inpipes [current_in].active); + bool fetched = inpipes [current_in].reader->read (msg_); + zmq_assert (fetched); + more_in = msg_->flags & ZMQ_MSG_MORE; + if (!more_in) { + current_in++; + if (current_in >= inpipes.size ()) + current_in = 0; + } + return 0; + } + + // Round-robin over the pipes to get the next message. + for (int count = inpipes.size (); count != 0; count--) { + + // Try to fetch new message. + bool fetched; + if (!inpipes [current_in].active) + fetched = false; + else + fetched = inpipes [current_in].reader->check_read (); + + // If we have a message, create a prefix and return it to the caller. + if (fetched) { + int rc = zmq_msg_init_size (msg_, + inpipes [current_in].identity.size ()); + zmq_assert (rc == 0); + memcpy (zmq_msg_data (msg_), inpipes [current_in].identity.data (), + zmq_msg_size (msg_)); + msg_->flags = ZMQ_MSG_MORE; + more_in = true; + return 0; + } + + // If me don't have a message, move to next pipe. + current_in++; + if (current_in >= inpipes.size ()) + current_in = 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::xrep_t::xhas_in () +{ + // There are subsequent parts of the partly-read message available. + if (more_in) + 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 = inpipes.size (); count != 0; count--) { + if (inpipes [current_in].active && + inpipes [current_in].reader->check_read ()) + return true; + current_in++; + if (current_in >= inpipes.size ()) + current_in = 0; + } + + return false; +} + +bool zmq::xrep_t::xhas_out () +{ + // In theory, XREP socket is always ready for writing. Whether actual + // attempt to write succeeds depends on whitch pipe the message is going + // to be routed to. + return true; +} + + |