]> git.ipfire.org Git - thirdparty/freeswitch.git/commitdiff
Patch from Rob Charlton to use rpc:call instead of spawn and to make the registered...
authorAndrew Thompson <andrew@hijacked.us>
Wed, 28 Jan 2009 19:26:37 +0000 (19:26 +0000)
committerAndrew Thompson <andrew@hijacked.us>
Wed, 28 Jan 2009 19:26:37 +0000 (19:26 +0000)
git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@11542 d0543943-73ff-0310-b7d9-9358b9ac24b2

src/mod/event_handlers/mod_erlang_event/ei_helpers.c
src/mod/event_handlers/mod_erlang_event/handle_msg.c
src/mod/event_handlers/mod_erlang_event/mod_erlang_event.c
src/mod/event_handlers/mod_erlang_event/mod_erlang_event.h

index f8b5f6cc3efc4d032b2582a15f6142547859b581..d206988de46ccdd9f2e5999e0c0f58905660758a 100644 (file)
@@ -122,6 +122,24 @@ void ei_encode_switch_event_tag(ei_x_buff *ebuf, switch_event_t *event, char *ta
        ei_encode_switch_event_headers(ebuf, event);
 }
 
+/* function to make rpc call to remote node to retrieve a pid - 
+   calls module:function(Ref). The response comes back as
+   {rex, {Ref, Pid}}
+ */
+int ei_pid_from_rpc(struct ei_cnode_s *ec, int sockfd, erlang_ref *ref, char *module, char *function)
+{
+       ei_x_buff buf;
+       ei_x_new(&buf);
+       ei_x_encode_list_header(&buf, 1);
+       ei_init_ref(ec, ref);
+       ei_x_encode_ref(&buf, ref);
+       ei_x_encode_empty_list(&buf);
+
+       ei_rpc_to(ec, sockfd, module, function, buf.buff, buf.index);
+       ei_x_free(&buf);
+
+       return 0;
+}
 
 /* function to spawn a process on a remote node */
 int ei_spawn(struct ei_cnode_s *ec, int sockfd, erlang_ref *ref, char *module, char *function, int argc, char **argv)
index 99bde11fbe0908c6372e209df2b290a05918b5f8..455e2be9e3cf58820cc78214960f27026041ad61 100644 (file)
@@ -37,6 +37,8 @@
 
 static char *MARKER = "1";
 
+static switch_status_t handle_ref_tuple(listener_t *listener, erlang_msg *msg, ei_x_buff *buf, ei_x_buff *rbuf);
+
 static void *SWITCH_THREAD_FUNC api_exec(switch_thread_t *thread, void *obj)
 {
        switch_bool_t r = SWITCH_TRUE;
@@ -519,15 +521,18 @@ static switch_status_t handle_msg_bind(listener_t *listener, erlang_msg *msg, ei
        return SWITCH_STATUS_SUCCESS;
 }
 
-/* {handlecall,<uuid>,<handler process registered name>} */
-static switch_status_t handle_msg_handlecall(listener_t *listener, int arity, ei_x_buff *buf, ei_x_buff *rbuf)
+/* {handlecall,<uuid>,<handler process registered name>}
+   or
+   {handlecall,<uuid>} to send messages back to the sender
+ */
+static switch_status_t handle_msg_handlecall(listener_t *listener, erlang_msg *msg, int arity, ei_x_buff *buf, ei_x_buff *rbuf)
 {
        char reg_name[MAXATOMLEN];
        char uuid_str[SWITCH_UUID_FORMATTED_LENGTH + 1];
 
-       if (arity != 3 ||
-               ei_decode_string_or_binary(buf->buff, &buf->index, SWITCH_UUID_FORMATTED_LENGTH, uuid_str) ||
-               ei_decode_atom(buf->buff, &buf->index, reg_name)) {
+       if (arity < 2 || arity > 3 ||
+               (arity==3 && ei_decode_atom(buf->buff, &buf->index, reg_name)) ||
+               ei_decode_string_or_binary(buf->buff, &buf->index, SWITCH_UUID_FORMATTED_LENGTH, uuid_str)) {
                ei_x_encode_tuple_header(rbuf, 2);
                ei_x_encode_atom(rbuf, "error");
                ei_x_encode_atom(rbuf, "badarg");
@@ -535,7 +540,8 @@ static switch_status_t handle_msg_handlecall(listener_t *listener, int arity, ei
                switch_core_session_t *session;
                if (!switch_strlen_zero(uuid_str) && (session = switch_core_session_locate(uuid_str))) {
                        /* create a new session list element and attach it to this listener */
-                       if (attach_call_to_registered_process(listener, reg_name, session)) {
+                       if ((arity==2 && attach_call_to_pid(listener, &msg->from, session)) ||
+                               (arity==3 && attach_call_to_registered_process(listener, reg_name, session))) {
                                ei_x_encode_atom(rbuf, "ok");
                        } else {
                                ei_x_encode_tuple_header(rbuf, 2);
@@ -551,6 +557,28 @@ static switch_status_t handle_msg_handlecall(listener_t *listener, int arity, ei
        return SWITCH_STATUS_SUCCESS;
 }
 
+/* catch the response to ei_rpc_to (which comes back as {rex, {Ref, Pid}}
+   The {Ref,Pid} bit can be handled by handle_ref_tuple
+ */
+static switch_status_t handle_msg_rpcresponse(listener_t *listener, erlang_msg *msg, int arity, ei_x_buff *buf, ei_x_buff *rbuf)
+{
+       int type, size, arity2, tmpindex;
+
+       ei_get_type(buf->buff, &buf->index, &type, &size);
+       switch(type) {
+       case ERL_SMALL_TUPLE_EXT :
+       case ERL_LARGE_TUPLE_EXT :
+               tmpindex = buf->index;
+               ei_decode_tuple_header(buf->buff, &tmpindex, &arity2);
+               return handle_ref_tuple(listener,msg,buf,rbuf);
+       default:
+               switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Unknown rpc response\n");
+               break;
+       }
+       /* no reply */
+       return SWITCH_STATUS_FALSE;
+}
+
 static switch_status_t handle_msg_tuple(listener_t *listener, erlang_msg *msg, ei_x_buff *buf, ei_x_buff *rbuf)
 {
        char tupletag[MAXATOMLEN];
@@ -583,7 +611,9 @@ static switch_status_t handle_msg_tuple(listener_t *listener, erlang_msg *msg, e
                } else if (!strncmp(tupletag, "bind", MAXATOMLEN)) {
                        ret = handle_msg_bind(listener,msg,buf,rbuf);
                } else if (!strncmp(tupletag, "handlecall", MAXATOMLEN)) {
-                       ret = handle_msg_handlecall(listener,arity,buf,rbuf);
+                       ret = handle_msg_handlecall(listener,msg,arity,buf,rbuf);
+               } else if (!strncmp(tupletag, "rex", MAXATOMLEN)) {
+                       ret = handle_msg_rpcresponse(listener,msg,arity,buf,rbuf);
                } else {
                        ei_x_encode_tuple_header(rbuf, 2);
                        ei_x_encode_atom(rbuf, "error");
@@ -701,7 +731,8 @@ static switch_status_t handle_ref_tuple(listener_t *listener, erlang_msg *msg, e
                switch_core_hash_insert(listener->spawn_pid_hash, hash, pid);
        }
 
-       return SWITCH_STATUS_SUCCESS;
+       /* no reply */
+       return SWITCH_STATUS_FALSE;
 }
 
 
index a5223d4b88c3b22d7ef2eb8130672fe09247652a..8f78dfb20140bd5ffee370a7cdaca3a982b9d243 100644 (file)
@@ -187,8 +187,8 @@ static void event_handler(switch_event_t *event)
                l = lp;
                lp = lp->next;
 
-               /* test all of the sessions attached to this event in case
-                  one of them should receive it as well
+               /* test all of the sessions attached to this listener in case
+                  one of them should receive the event as well
                 */
 
                send_event_to_attached_sessions(l,event);
@@ -684,9 +684,10 @@ static void listener_main_loop(listener_t *listener)
                ei_x_buff rbuf;
                ei_x_new_with_version(&rbuf);
 
-               switch_mutex_lock(listener->sock_mutex);
+               /* do we need the mutex when reading? */
+               /*switch_mutex_lock(listener->sock_mutex);*/
                status = ei_xreceive_msg_tmo(listener->sockfd, &msg, &buf, 100);
-               switch_mutex_unlock(listener->sock_mutex);
+               /*switch_mutex_unlock(listener->sock_mutex);*/
 
                switch(status) {
                        case ERL_TICK :
@@ -780,7 +781,9 @@ static switch_bool_t check_inbound_acl(listener_t* listener)
                                        ei_x_encode_atom(&rbuf, "error");
                                        ei_x_encode_atom(&rbuf, "acldeny");
 
+                                       switch_mutex_lock(listener->sock_mutex);
                                        ei_send(listener->sockfd, &msg.from, rbuf.buff, rbuf.index);
+                                       switch_mutex_unlock(listener->sock_mutex);
 #ifdef EI_DEBUG
                                        ei_x_print_msg(&rbuf, &msg.from, 1);
 #endif
@@ -1026,6 +1029,33 @@ session_elem_t* attach_call_to_registered_process(listener_t* listener, char* re
        return session_element;
 }
 
+session_elem_t* attach_call_to_pid(listener_t* listener, erlang_pid* pid, switch_core_session_t *session)
+{
+       /* create a session list element */
+       session_elem_t* session_element = NULL;
+       if (!(session_element = switch_core_alloc(switch_core_session_get_pool(session), sizeof(*session_element)))) {
+               switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Failed to allocate session element\n");
+       }
+       else {
+               if (SWITCH_STATUS_SUCCESS != switch_core_session_read_lock(session)) {
+                       switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Failed to get session read lock\n");
+               }
+               else {
+                       session_element->session = session;
+                       session_element->process.type = ERLANG_PID;
+                       memcpy(&session_element->process.pid, pid, sizeof(erlang_pid));
+                       switch_set_flag(session_element, LFLAG_SESSION_ALIVE);
+                       switch_clear_flag(session_element, LFLAG_OUTBOUND_INIT);
+                       switch_queue_create(&session_element->event_queue, SWITCH_CORE_QUEUE_LEN, switch_core_session_get_pool(session));
+                       switch_mutex_init(&session_element->flag_mutex, SWITCH_MUTEX_NESTED, switch_core_session_get_pool(session));
+                       /* attach the session to the listener */
+                       add_session_elem_to_listener(listener,session_element);
+
+                       ei_link(listener, ei_self(listener->ec), pid);
+               }
+       }
+       return session_element;
+}
 
 session_elem_t* attach_call_to_spawned_process(listener_t* listener, char *module, char *function, switch_core_session_t *session)
 {
@@ -1039,7 +1069,7 @@ session_elem_t* attach_call_to_spawned_process(listener_t* listener, char *modul
                        switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Failed to get session read lock\n");
                }
                else {
-                       char *argv[1], hash[100];
+                       char hash[100];
                        int i = 0;
                        session_element->session = session;
                        erlang_pid *pid;
@@ -1061,13 +1091,20 @@ session_elem_t* attach_call_to_spawned_process(listener_t* listener, char *modul
                                ei_x_encode_atom(&rbuf, "new_pid");
                                ei_x_encode_ref(&rbuf, &ref);
                                ei_x_encode_pid(&rbuf, ei_self(listener->ec));
+                               /* should lock with mutex? */
                                ei_reg_send(listener->ec, listener->sockfd, module, rbuf.buff, rbuf.index);
 #ifdef EI_DEBUG
                                ei_x_print_reg_msg(&rbuf, module, 1);
 #endif
                                ei_x_free(&rbuf);
                        } else {
+                               switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "rpc call: %s:%s(Ref)\n", module, function);
+                               /* should lock with mutex? */
+                               ei_pid_from_rpc(listener->ec, listener->sockfd, &ref, module, function);
+                               /*
+                               char *argv[1];
                                ei_spawn(listener->ec, listener->sockfd, &ref, module, function, 0, argv);
+                               */
                        }
 
                        ei_hash_ref(&ref, hash);
@@ -1091,7 +1128,8 @@ session_elem_t* attach_call_to_spawned_process(listener_t* listener, char *modul
                        switch_clear_flag(session_element, LFLAG_OUTBOUND_INIT);
                        switch_clear_flag(session_element, LFLAG_WAITING_FOR_PID);
 
-                       ei_link(listener, ei_self(listener->ec), pid);
+                       /* this hangs because it can never get hold of the socket mutex */
+                        ei_link(listener, ei_self(listener->ec), pid); 
                }
        }
        return session_element;
index 15ff9da3d39267fd04e7c6d4f8a1f035367e3943..b90eff8eff958d1ce7d6d4daed37ab0343dd03fc 100644 (file)
@@ -192,6 +192,7 @@ int handle_msg(listener_t *listener, erlang_msg *msg, ei_x_buff *buf, ei_x_buff
 void ei_link(listener_t *listener, erlang_pid *from, erlang_pid *to);
 void ei_encode_switch_event_headers(ei_x_buff *ebuf, switch_event_t *event);
 void ei_encode_switch_event_tag(ei_x_buff *ebuf, switch_event_t *event, char *tag);
+int ei_pid_from_rpc(struct ei_cnode_s *ec, int sockfd, erlang_ref *ref, char *module, char *function);
 int ei_spawn(struct ei_cnode_s *ec, int sockfd, erlang_ref *ref, char *module, char *function, int argc, char **argv);
 void ei_init_ref(struct ei_cnode_s *ec, erlang_ref *ref);
 void ei_x_print_reg_msg(ei_x_buff *buf, char *dest, int send);
@@ -215,6 +216,7 @@ switch_status_t initialise_ei(struct ei_cnode_s *ec);
 
 /* mod_erlang_event.c */
 session_elem_t* attach_call_to_registered_process(listener_t* listener, char* reg_name, switch_core_session_t *session);
+session_elem_t* attach_call_to_pid(listener_t* listener, erlang_pid* pid, switch_core_session_t *session);
 session_elem_t* attach_call_to_spawned_process(listener_t* listener, char *module, char *function, switch_core_session_t *session);
 
 /* For Emacs: