XS_PLUGIN and XS_FILTER implementation

This patch introduces following features:
- XS_PLUGIN context option to add plugins to libxs
- XS_FILTER option to switch between different filter types
- Automatic loading of plug-ins is *not* implemented.

From the implementation point of view:
- standard prefix filter is implemented as a pluggable filter
- trie_t and mtrie_t are joined into a single class
- the code for 0MQ/3.1 compatibility is left in in the form of comments
- new test for testing re-subscriptions is added
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

1 files changed, 17 insertions, 2 deletions

diff --git a/src/sub.cpp b/src/sub.cpp
index 3065345..442dd9b 100644
--- a/src/sub.cpp
+++ b/src/sub.cpp
@@ -21,6 +21,7 @@
 
 #include "sub.hpp"
 #include "msg.hpp"
+#include "wire.hpp"
 
 xs::sub_t::sub_t (class ctx_t *parent_, uint32_t tid_, int sid_) :
     xsub_t (parent_, tid_, sid_)
@@ -51,14 +52,28 @@ int xs::sub_t::xsetsockopt (int option_, const void *optval_,
 
     //  Create the subscription message.
     msg_t msg;
+    int rc = msg.init_size (optvallen_ + 4);
+    errno_assert (rc == 0);
+    unsigned char *data = (unsigned char*) msg.data ();
+    if (option_ == XS_SUBSCRIBE)
+        put_uint16 (data, XS_CMD_SUBSCRIBE);
+    else if (option_ == XS_UNSUBSCRIBE)
+        put_uint16 (data, XS_CMD_UNSUBSCRIBE);
+    put_uint16 (data + 2, options.filter_id);
+    memcpy (data + 4, optval_, optvallen_);
+
+#if 0
+    //  TODO: This is 0MQ/3.1 protocol.
+    msg_t msg;
     int rc = msg.init_size (optvallen_ + 1);
     errno_assert (rc == 0);
     unsigned char *data = (unsigned char*) msg.data ();
     if (option_ == XS_SUBSCRIBE)
-        *data = 1;
+        data [0] = 1;
     else if (option_ == XS_UNSUBSCRIBE)
-        *data = 0;
+        data [0] = 0;
     memcpy (data + 1, optval_, optvallen_);
+#endif
 
     //  Pass it further on in the stack.
     int err = 0;