Implement SP wire protocol

Implements the SP wire protocol, and infrastructure for legacy wire
protocol support.

Also added an XS_SERVICE_ID socket option to set the service id and renamed
the XS_PROTOCOL option to XS_PATTERN_VERSION.

The following pattern versions are supported:

PAIR:     v3
PUBSUB:   v1 (legacy), v4
REQREP:   v2
PIPELINE: v3
SURVEY:   v2

Note that all existing pattern versions have been bumped by 1 to allow for
use of legacy protocols (otherwise there would be no way to distinguish
between e.g. PUBSUB v3 and PUBSUB v3 using SP).

Signed-off-by: Martin Lucina <martin@lucina.net>

1 files changed, 48 insertions, 7 deletions

diff --git a/src/xsub.cpp b/src/xsub.cpp
index 7272a8e..9255ceb 100644
--- a/src/xsub.cpp
+++ b/src/xsub.cpp
@@ -29,6 +29,10 @@ xs::xsub_t::xsub_t (class ctx_t *parent_, uint32_t tid_, int sid_) :
     socket_base_t (parent_, tid_, sid_)
 {
     options.type = XS_XSUB;
+    options.sp_pattern = SP_PUBSUB;
+    options.sp_version = 4;
+    options.sp_role = SP_PUBSUB_SUB;
+    options.sp_complement = SP_PUBSUB_PUB;
 
     //  When socket is being closed down we don't want to wait till pending
     //  subscription commands are sent to the wire.
@@ -42,6 +46,42 @@ xs::xsub_t::~xsub_t ()
 {
 }
 
+int xs::xsub_t::xsetsockopt (int option_, const void *optval_,
+    size_t optvallen_)
+{
+    if (option_ != XS_PATTERN_VERSION) {
+        errno = EINVAL;
+        return -1;
+    }
+
+    if (optvallen_ != sizeof (int)) {
+        errno = EINVAL;
+        return -1;
+    }
+
+    if (!optval_) {
+        errno = EFAULT;
+        return -1;
+    }
+
+    int version = *(int *) optval_;
+    switch (version) {
+    case 1:
+        options.legacy_protocol = true;
+        options.sp_version = 1;
+        break;
+    case 3:
+        options.legacy_protocol = false;
+        options.sp_version = 3;
+        break;
+    default:
+        errno = EINVAL;
+        return -1;
+    }
+
+    return 0;
+}
+
 void xs::xsub_t::xattach_pipe (pipe_t *pipe_, bool icanhasall_)
 {
     xs_assert (pipe_);
@@ -49,7 +89,7 @@ void xs::xsub_t::xattach_pipe (pipe_t *pipe_, bool icanhasall_)
 
     //  Pipes with 0MQ/2.1-style protocol are not eligible for accepting
     //  subscriptions.
-    if (pipe_->get_protocol () == 1)
+    if (pipe_->get_sp_version () == 1)
         return;
 
     dist.attach (pipe_);
@@ -75,14 +115,14 @@ void xs::xsub_t::xwrite_activated (pipe_t *pipe_)
 void xs::xsub_t::xterminated (pipe_t *pipe_)
 {
     fq.terminated (pipe_);
-    if (pipe_->get_protocol () != 1)
+    if (pipe_->get_sp_version () != 1)
         dist.terminated (pipe_);
 }
 
 void xs::xsub_t::xhiccuped (pipe_t *pipe_)
 {
     //  In 0MQ/2.1 protocol there is no subscription forwarding.
-    if (pipe_->get_protocol () == 1)
+    if (pipe_->get_sp_version () == 1)
         return;
 
     //  Send all the cached subscriptions to the new upstream peer.
@@ -104,13 +144,13 @@ int xs::xsub_t::xsend (msg_t *msg_, int flags_)
     }
     int cmd = get_uint16 (data);
     int filter_id = get_uint16 (data + 2);
-    if (cmd != XS_CMD_SUBSCRIBE && cmd != XS_CMD_UNSUBSCRIBE) {
+    if (cmd != SP_PUBSUB_CMD_SUBSCRIBE && cmd != SP_PUBSUB_CMD_UNSUBSCRIBE) {
         errno = EINVAL;
         return -1;
     }
 
     //  Process the subscription.
-    if (cmd == XS_CMD_SUBSCRIBE) {
+    if (cmd == SP_PUBSUB_CMD_SUBSCRIBE) {
         subscriptions_t::iterator it = subscriptions.insert (
            std::make_pair (std::make_pair (filter_id,
            blob_t (data + 4, size - 4)), 0)).first;
@@ -118,7 +158,7 @@ int xs::xsub_t::xsend (msg_t *msg_, int flags_)
         if (it->second == 1)
             return dist.send_to_all (msg_, flags_);
     }
-    else if (cmd == XS_CMD_UNSUBSCRIBE) {
+    else if (cmd == SP_PUBSUB_CMD_UNSUBSCRIBE) {
         subscriptions_t::iterator it = subscriptions.find (
             std::make_pair (filter_id, blob_t (data + 4, size - 4)));
         if (it != subscriptions.end ()) {
@@ -162,7 +202,8 @@ void xs::xsub_t::send_subscription (pipe_t *pipe_, bool subscribe_,
     int rc = msg.init_size (size_ + 4);
     xs_assert (rc == 0);
     unsigned char *data = (unsigned char*) msg.data ();
-    put_uint16 (data, subscribe_ ? XS_CMD_SUBSCRIBE : XS_CMD_UNSUBSCRIBE);
+    put_uint16 (data, subscribe_ ? SP_PUBSUB_CMD_SUBSCRIBE :
+        SP_PUBSUB_CMD_UNSUBSCRIBE);
     put_uint16 (data + 2, filter_id_);
     memcpy (data + 4, data_, size_);