diff options
Diffstat (limited to 'src/req.cpp')
-rw-r--r-- | src/req.cpp | 286 |
1 files changed, 286 insertions, 0 deletions
diff --git a/src/req.cpp b/src/req.cpp new file mode 100644 index 0000000..f3695a2 --- /dev/null +++ b/src/req.cpp @@ -0,0 +1,286 @@ +/* + 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 "req.hpp" +#include "err.hpp" +#include "pipe.hpp" + +zmq::req_t::req_t (class app_thread_t *parent_) : + socket_base_t (parent_), + active (0), + current (0), + receiving_reply (false), + reply_pipe_active (false), + more (false), + reply_pipe (NULL) +{ + options.requires_in = true; + options.requires_out = true; +} + +zmq::req_t::~req_t () +{ +} + +void zmq::req_t::xattach_pipes (class reader_t *inpipe_, + class writer_t *outpipe_, const blob_t &peer_identity_) +{ + zmq_assert (inpipe_ && outpipe_); + zmq_assert (in_pipes.size () == out_pipes.size ()); + + in_pipes.push_back (inpipe_); + in_pipes.swap (active, in_pipes.size () - 1); + + out_pipes.push_back (outpipe_); + out_pipes.swap (active, out_pipes.size () - 1); + + active++; +} + +void zmq::req_t::xdetach_inpipe (class reader_t *pipe_) +{ + zmq_assert (!receiving_reply || !more || reply_pipe != pipe_); + + zmq_assert (pipe_); + zmq_assert (in_pipes.size () == out_pipes.size ()); + + // TODO: The pipe we are awaiting the reply from is detached. What now? + // Return ECONNRESET from subsequent recv? + if (receiving_reply && pipe_ == reply_pipe) { + zmq_assert (false); + } + + in_pipes_t::size_type index = in_pipes.index (pipe_); + + if (out_pipes [index]) + out_pipes [index]->term (); + in_pipes.erase (index); + out_pipes.erase (index); + if (index < active) { + active--; + if (current == active) + current = 0; + } +} + +void zmq::req_t::xdetach_outpipe (class writer_t *pipe_) +{ + zmq_assert (receiving_reply || !more || out_pipes [current] != pipe_); + + zmq_assert (pipe_); + zmq_assert (in_pipes.size () == out_pipes.size ()); + + out_pipes_t::size_type index = out_pipes.index (pipe_); + + if (in_pipes [index]) + in_pipes [index]->term (); + in_pipes.erase (index); + out_pipes.erase (index); + if (index < active) { + active--; + if (current == active) + current = 0; + } +} + +void zmq::req_t::xkill (class reader_t *pipe_) +{ + zmq_assert (receiving_reply); + zmq_assert (pipe_ == reply_pipe); + + reply_pipe_active = false; +} + +void zmq::req_t::xrevive (class reader_t *pipe_) +{ + // TODO: Actually, misbehaving peer can cause this kind of thing. + // Handle it decently, presumably kill the offending connection. + zmq_assert (pipe_ == reply_pipe); + reply_pipe_active = true; +} + +void zmq::req_t::xrevive (class writer_t *pipe_) +{ + out_pipes_t::size_type index = out_pipes.index (pipe_); + zmq_assert (index >= active); + + if (in_pipes [index] != NULL) { + in_pipes.swap (index, active); + out_pipes.swap (index, active); + active++; + } +} + +int zmq::req_t::xsetsockopt (int option_, const void *optval_, + size_t optvallen_) +{ + errno = EINVAL; + return -1; +} + +int zmq::req_t::xsend (zmq_msg_t *msg_, int flags_) +{ + // If we've sent a request and we still haven't got the reply, + // we can't send another request. + if (receiving_reply) { + errno = EFSM; + return -1; + } + + while (active > 0) { + if (out_pipes [current]->check_write ()) + break; + + zmq_assert (!more); + active--; + if (current < active) { + in_pipes.swap (current, active); + out_pipes.swap (current, active); + } + else + current = 0; + } + + if (active == 0) { + errno = EAGAIN; + return -1; + } + + // If we are starting to send the request, generate a prefix. + if (!more) { + zmq_msg_t prefix; + int rc = zmq_msg_init (&prefix); + zmq_assert (rc == 0); + prefix.flags |= ZMQ_MSG_MORE; + bool written = out_pipes [current]->write (&prefix); + zmq_assert (written); + } + + // Push the message to the selected pipe. + bool written = out_pipes [current]->write (msg_); + zmq_assert (written); + more = msg_->flags & ZMQ_MSG_MORE; + if (!more) { + out_pipes [current]->flush (); + receiving_reply = true; + reply_pipe = in_pipes [current]; + + // We can safely assume that the reply pipe is active as the last time + // we've used it we've read the reply and haven't tried to read from it + // anymore. + reply_pipe_active = true; + + // Move to the next pipe (load-balancing). + current = (current + 1) % active; + } + + // Detach the message from the data buffer. + int rc = zmq_msg_init (msg_); + zmq_assert (rc == 0); + + return 0; +} + +int zmq::req_t::xrecv (zmq_msg_t *msg_, int flags_) +{ + // Deallocate old content of the message. + int rc = zmq_msg_close (msg_); + zmq_assert (rc == 0); + + // If request wasn't send, we can't wait for reply. + if (!receiving_reply) { + zmq_msg_init (msg_); + errno = EFSM; + return -1; + } + + // Get the reply from the reply pipe. + if (!reply_pipe_active || !reply_pipe->read (msg_)) { + zmq_msg_init (msg_); + errno = EAGAIN; + return -1; + } + + // If we are starting to receive new reply, check whether prefix + // is well-formed and drop it. + if (!more) { + zmq_assert (msg_->flags & ZMQ_MSG_MORE); + zmq_assert (zmq_msg_size (msg_) == 0); + rc = zmq_msg_close (msg_); + zmq_assert (rc == 0); + + // Get the actual reply. + bool recvd = reply_pipe->read (msg_); + zmq_assert (recvd); + } + + // If this was last part of the reply, switch to request phase. + more = msg_->flags & ZMQ_MSG_MORE; + if (!more) { + receiving_reply = false; + reply_pipe = NULL; + } + + return 0; +} + +bool zmq::req_t::xhas_in () +{ + if (receiving_reply && more) + return true; + + if (!receiving_reply || !reply_pipe_active) + return false; + + zmq_assert (reply_pipe); + if (!reply_pipe->check_read ()) { + reply_pipe_active = false; + return false; + } + + return true; +} + +bool zmq::req_t::xhas_out () +{ + if (!receiving_reply && more) + return true; + + if (receiving_reply) + return false; + + while (active > 0) { + if (out_pipes [current]->check_write ()) + return true;; + + active--; + if (current < active) { + in_pipes.swap (current, active); + out_pipes.swap (current, active); + } + else + current = 0; + } + + return false; +} + + |