API: Python and Unix domain socket improvement

Handle the case where buffer overflows.
Then SOCK_SEQPACKET assumption that multiple API messages
are not returned by recv() is broken. Use SOCK_STREAM for
API exchanges instead.

Add support for running tests over sockets.
make test SOCKET=1

Change-Id: Ibe5fd69b1bf617de4c7ba6cce0a7c2b3f97a2821
Signed-off-by: Ole Troan <ot@cisco.com>

5 files changed, 24 insertions, 38 deletions

diff --git a/src/plugins/igmp/igmp.api b/src/plugins/igmp/igmp.api
index db47905ae6f..b061c5e1a35 100644
--- a/src/plugins/igmp/igmp.api
+++ b/src/plugins/igmp/igmp.api
@@ -215,8 +215,6 @@ service {
  */
 define igmp_event
 {
-  u32 context;
-
   u32 sw_if_index;
   vl_api_filter_mode_t filter;
   vl_api_ip4_address_t saddr;
diff --git a/src/plugins/igmp/igmp_api.c b/src/plugins/igmp/igmp_api.c
index d619abdd893..548d828267f 100644
--- a/src/plugins/igmp/igmp_api.c
+++ b/src/plugins/igmp/igmp_api.c
@@ -60,7 +60,7 @@ _(IGMP_CLEAR_INTERFACE, igmp_clear_interface)                                  \
 _(IGMP_CLEAR_INTERFACE, igmp_clear_interface)                                  \
 _(IGMP_GROUP_PREFIX_SET, igmp_group_prefix_set)                                \
 _(IGMP_GROUP_PREFIX_DUMP, igmp_group_prefix_dump)                              \
-_(WANT_IGMP_EVENTS, want_igmp_events)                                          \
+_(WANT_IGMP_EVENTS, want_igmp_events)
 
 static void
 vl_api_igmp_listen_t_handler (vl_api_igmp_listen_t * mp)
@@ -373,7 +373,7 @@ vl_api_want_igmp_events_t_handler (vl_api_want_igmp_events_t * mp)
     }
   rv = VNET_API_ERROR_INVALID_REGISTRATION;
 
-done:;
+done:
   REPLY_MACRO (VL_API_WANT_IGMP_EVENTS_REPLY + im->msg_id_base);
 }
 
@@ -399,7 +399,6 @@ VL_MSG_API_REAPER_FUNCTION (want_igmp_events_reaper);
 
 void
 send_igmp_event (vl_api_registration_t * rp,
-		 u32 context,
 		 igmp_filter_mode_t filter,
 		 u32 sw_if_index,
 		 const ip46_address_t * saddr, const ip46_address_t * gaddr)
@@ -408,7 +407,6 @@ send_igmp_event (vl_api_registration_t * rp,
   clib_memset (mp, 0, sizeof (*mp));
 
   mp->_vl_msg_id = ntohs ((VL_API_IGMP_EVENT) + igmp_main.msg_id_base);
-  mp->context = context;
   mp->sw_if_index = htonl (sw_if_index);
   mp->filter = htonl (filter);
   clib_memcpy (&mp->saddr, &saddr->ip4, sizeof (ip4_address_t));
@@ -440,7 +438,7 @@ igmp_event (igmp_filter_mode_t filter,
     ({
       rp = vl_api_client_index_to_registration (api_client->client_index);
       if (rp)
-        send_igmp_event (rp, 0, filter, sw_if_index, saddr, gaddr);
+        send_igmp_event (rp, filter, sw_if_index, saddr, gaddr);
     }));
   /* *INDENT-ON* */
 }
diff --git a/src/vlibmemory/socket_api.c b/src/vlibmemory/socket_api.c
index a8423d11ccb..a8a45a7e6bc 100644
--- a/src/vlibmemory/socket_api.c
+++ b/src/vlibmemory/socket_api.c
@@ -722,8 +722,7 @@ vl_sock_api_init (vlib_main_t * vm)
       vec_free (tmp);
     }
 
-  sock->flags = CLIB_SOCKET_F_IS_SERVER | CLIB_SOCKET_F_SEQPACKET |
-    CLIB_SOCKET_F_ALLOW_GROUP_WRITE;
+  sock->flags = CLIB_SOCKET_F_IS_SERVER | CLIB_SOCKET_F_ALLOW_GROUP_WRITE;
   error = clib_socket_init (sock);
   if (error)
     return error;
diff --git a/src/vlibmemory/socket_client.c b/src/vlibmemory/socket_client.c
index ca1e53538ae..96330ce481a 100644
--- a/src/vlibmemory/socket_client.c
+++ b/src/vlibmemory/socket_client.c
@@ -374,8 +374,7 @@ vl_socket_client_connect (char *socket_path, char *client_name,
 
   sock = &scm->client_socket;
   sock->config = socket_path;
-  sock->flags = CLIB_SOCKET_F_IS_CLIENT
-    | CLIB_SOCKET_F_SEQPACKET | CLIB_SOCKET_F_NON_BLOCKING_CONNECT;
+  sock->flags = CLIB_SOCKET_F_IS_CLIENT | CLIB_SOCKET_F_NON_BLOCKING_CONNECT;
 
   if ((error = clib_socket_init (sock)))
     {
diff --git a/src/vpp-api/python/vpp_papi/vpp_transport_socket.py b/src/vpp-api/python/vpp_papi/vpp_transport_socket.py
index 4341cad3e90..63cb6a6e9e7 100644
--- a/src/vpp-api/python/vpp_papi/vpp_transport_socket.py
+++ b/src/vpp-api/python/vpp_papi/vpp_transport_socket.py
@@ -70,7 +70,7 @@ class VppTransport(object):
     def connect(self, name, pfx, msg_handler, rx_qlen):
 
         # Create a UDS socket
-        self.socket = socket.socket(socket.AF_UNIX, socket.SOCK_SEQPACKET)
+        self.socket = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
         self.socket.settimeout(self.read_timeout)
 
         # Connect the socket to the port where the server is listening
@@ -150,36 +150,28 @@ class VppTransport(object):
         n = self.socket.send(buf)
 
     def _read(self):
-        # Header and message
-        try:
-            msg = self.socket.recv(4096)
-            if len(msg) == 0:
-                return None
-        except socket.error as message:
-            logging.error(message)
-            raise
-
-        (_, l, _) = self.header.unpack(msg[:16])
+        hdr = self.socket.recv(16)
+        if not hdr:
+            return
+        (_, l, _) = self.header.unpack(hdr) # If at head of message
 
+        # Read rest of message
+        msg = self.socket.recv(l)
         if l > len(msg):
-            buf = bytearray(l + 16)
+            nbytes = len(msg)
+            buf = bytearray(l)
             view = memoryview(buf)
-            view[:4096] = msg
-            view = view[4096:]
-            # Read rest of message
-            remaining_bytes = l - 4096 + 16
-            while remaining_bytes > 0:
-                bytes_to_read = (remaining_bytes if remaining_bytes
-                                 <= 4096 else 4096)
-                nbytes = self.socket.recv_into(view, bytes_to_read)
-                if nbytes == 0:
-                    logging.error('recv failed')
-                    break
+            view[:nbytes] = msg
+            view = view[nbytes:]
+            left = l - nbytes
+            while left:
+                nbytes = self.socket.recv_into(view, left)
                 view = view[nbytes:]
-                remaining_bytes -= nbytes
-        else:
-            buf = msg
-        return buf[16:]
+                left -= nbytes
+            return buf
+        if l == len(msg):
+            return msg
+        raise VPPTransportSocketIOError(1, 'Unknown socket read error')
 
     def read(self):
         if not self.connected: