generic-library/libzmq
1
0
Fork 0
mirror of https://github.com/zeromq/libzmq.git synced 2025-10-28 19:52:00 +01:00
Code Issues Projects Releases Wiki Activity

New wire format for REQ/REP pattern

Browse Source 
This patch introduces two changes:
1. 32-bit ID is used to identify the peer instead of UUID
2. REQ socket seeds the label stack with unique 32-bit request ID
   It also drops any replies with non-matching request ID

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>
This commit is contained in:
Martin Sustrik
2011-06-22 11:02:16 +02:00
parent 10a93bb79f
commit ec81f8fb25
12 changed files with 344 additions and 70 deletions
Download Patch File Download Diff File Expand all files Collapse all files

38
src/req.cpp
View File

@@ -21,13 +21,21 @@
#include "req.hpp"
#include "err.hpp"
#include "msg.hpp"
#include "uuid.hpp"
#include "wire.hpp"
#include "random.hpp"
#include "likely.hpp"
zmq::req_t::req_t (class ctx_t *parent_, uint32_t tid_) :
xreq_t (parent_, tid_),
receiving_reply (false),
message_begins (true)
message_begins (true),
request_id (0)
{
options.type = ZMQ_REQ;
// Start the request ID sequence at an random point.
generate_random (&request_id, sizeof (request_id));
}
zmq::req_t::~req_t ()
@@ -43,12 +51,14 @@ int zmq::req_t::xsend (msg_t *msg_, int flags_)
return -1;
}
// First part of the request is empty message part (stack bottom).
// First part of the request is the request identity.
if (message_begins) {
msg_t prefix;
int rc = prefix.init ();
int rc = prefix.init_size (4);
errno_assert (rc == 0);
prefix.set_flags (msg_t::label);
unsigned char *data = (unsigned char*) prefix.data ();
put_uint32 (data, request_id);
rc = xreq_t::xsend (&prefix, flags_);
if (rc != 0)
return rc;
@@ -78,13 +88,28 @@ int zmq::req_t::xrecv (msg_t *msg_, int flags_)
return -1;
}
// First part of the reply should be empty message part (stack bottom).
// First part of the reply should be the original request ID.
if (message_begins) {
int rc = xreq_t::xrecv (msg_, flags_);
if (rc != 0)
return rc;
zmq_assert (msg_->flags () & msg_t::label);
zmq_assert (msg_->size () == 0);
zmq_assert (msg_->size () == 4);
unsigned char *data = (unsigned char*) msg_->data ();
if (unlikely (get_uint32 (data) != request_id)) {
// The request ID does not match. Drop the entire message.
while (true) {
int rc = xreq_t::xrecv (msg_, flags_);
errno_assert (rc == 0);
if (!(msg_->flags () & (msg_t::label | msg_t::more)))
break;
}
msg_->close ();
msg_->init ();
errno = EAGAIN;
return -1;
}
message_begins = false;
}
@@ -94,6 +119,7 @@ int zmq::req_t::xrecv (msg_t *msg_, int flags_)
// If the reply is fully received, flip the FSM into request-sending state.
if (!(msg_->flags () & (msg_t::more | msg_t::label))) {
request_id++;
receiving_reply = false;
message_begins = true;
}
@@ -103,6 +129,8 @@ int zmq::req_t::xrecv (msg_t *msg_, int flags_)
bool zmq::req_t::xhas_in ()
{
// TODO: Duplicates should be removed here.
if (!receiving_reply)
return false;