libctdb: add synchronous message handling and unregister, with tests.

[sahlberg/ctdb.git] / libctdb / messages.c

diff --git a/libctdb/messages.c b/libctdb/messages.c
index 7ad48d5dc834542fb6ce3edec2095057dbd229e6..b79857c52ff86f1ccbffaa7f6744160703ab5b67 100644 (file)
--- a/libctdb/messages.c
+++ b/libctdb/messages.c
@@ -6,6 +6,7 @@
 #include <ctdb_protocol.h>
 #include <stdlib.h>
 #include <string.h>
+#include <errno.h>
 
 /* Remove type-safety macros. */
 #undef ctdb_set_message_handler_send
@@ -17,7 +18,7 @@ struct message_handler_info {
 
        uint64_t srvid;
        ctdb_message_fn_t handler;
-       void *private_data;
+       void *handler_data;
 };
 
 void deliver_message(struct ctdb_connection *ctdb, struct ctdb_req_header *hdr)
@@ -30,9 +31,10 @@ void deliver_message(struct ctdb_connection *ctdb, struct ctdb_req_header *hdr)
        data.dptr = msg->data;
        data.dsize = msg->datalen;
 
+       /* Note: we want to call *every* handler: there may be more than one */
        for (i = ctdb->message_handlers; i; i = i->next) {
                if (i->srvid == msg->srvid) {
-                       i->handler(ctdb, msg->srvid, data, i->private_data);
+                       i->handler(ctdb, msg->srvid, data, i->handler_data);
                        found = true;
                }
        }
@@ -86,7 +88,7 @@ static void free_info(struct ctdb_connection *ctdb, struct ctdb_request *req)
 
 struct ctdb_request *
 ctdb_set_message_handler_send(struct ctdb_connection *ctdb, uint64_t srvid,
-                             ctdb_message_fn_t handler,
+                             ctdb_message_fn_t handler, void *handler_data,
                              ctdb_callback_t callback, void *private_data)
 {
        struct message_handler_info *info;
@@ -114,7 +116,7 @@ ctdb_set_message_handler_send(struct ctdb_connection *ctdb, uint64_t srvid,
 
        info->srvid = srvid;
        info->handler = handler;
-       info->private_data = private_data;
+       info->handler_data = handler_data;
 
        DEBUG(ctdb, LOG_DEBUG,
              "ctdb_set_message_handler_send: sending request %u for id %llu",
@@ -122,6 +124,69 @@ ctdb_set_message_handler_send(struct ctdb_connection *ctdb, uint64_t srvid,
        return req;
 }
 
+struct ctdb_request *
+ctdb_remove_message_handler_send(struct ctdb_connection *ctdb, uint64_t srvid,
+                                ctdb_message_fn_t handler, void *hdata,
+                                ctdb_callback_t callback, void *cbdata)
+{
+       struct message_handler_info *i;
+       struct ctdb_request *req;
+
+       for (i = ctdb->message_handlers; i; i = i->next) {
+               if (i->srvid == srvid
+                   && i->handler == handler && i->handler_data == hdata) {
+                       break;
+               }
+       }
+       if (!i) {
+               DEBUG(ctdb, LOG_ALERT,
+                     "ctdb_remove_message_handler_send: no such handler");
+               errno = ENOENT;
+               return NULL;
+       }
+
+       req = new_ctdb_control_request(ctdb, CTDB_CONTROL_DEREGISTER_SRVID,
+                                      CTDB_CURRENT_NODE, NULL, 0,
+                                      callback, cbdata);
+       if (!req) {
+               DEBUG(ctdb, LOG_ERR,
+                     "ctdb_remove_message_handler_send: allocating request");
+               return NULL;
+       }
+       req->hdr.control->srvid = srvid;
+       req->extra = i;
+
+       DEBUG(ctdb, LOG_DEBUG,
+             "ctdb_set_remove_handler_send: sending request %u for id %llu",
+             req->hdr.hdr->reqid, srvid);
+       return req;
+}
+
+bool ctdb_remove_message_handler_recv(struct ctdb_connection *ctdb,
+                                     struct ctdb_request *req)
+{
+       struct message_handler_info *handler = req->extra;
+       struct ctdb_reply_control *reply;
+
+       reply = unpack_reply_control(ctdb, req, CTDB_CONTROL_DEREGISTER_SRVID);
+       if (!reply) {
+               return false;
+       }
+       if (reply->status != 0) {
+               DEBUG(ctdb, LOG_ERR,
+                     "ctdb_remove_message_handler_recv: status %i",
+                     reply->status);
+               return false;
+       }
+
+       /* Remove ourselves from list of handlers. */
+       DLIST_REMOVE(ctdb->message_handlers, handler);
+       free(handler);
+       /* Crash if they call this again! */
+       req->extra = NULL;
+       return true;
+}
+
 bool ctdb_send_message(struct ctdb_connection *ctdb,
                      uint32_t pnn, uint64_t srvid,
                      TDB_DATA data)