discover: Don't free clients on write failure

Currently, if we see an error when writing to a client, we free the
client immediately. This means that any pending reads will be discarded.
Additionally, if a client disconnects before we have finished the writes in
discover_server_process_connection, we won't register the waiter to read
from the socket.

Instead of freeing the client on write failure, this change sets a flag
(se we don't continue to write), and we rely on the read EOF to free the
client. This means we don't drop incoming messages.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>

diff --git a/discover/discover-server.c b/discover/discover-server.c
index 25dbd1476cdd9d6cf2ba817d74716d7944e40542..2467e33dc97ac5b9cfc45c44576f18d6f969c79a 100644 (file)
--- a/discover/discover-server.c
+++ b/discover/discover-server.c
@@ -34,6 +34,7 @@ struct client {
        struct list_item list;
        struct waiter *waiter;
        int fd;
        struct list_item list;
        struct waiter *waiter;
        int fd;

+       bool remote_closed;

 };
 
 
 };
 
 


@@ -89,9 +90,12 @@ static int client_write_message(
 {
        int rc;
 
 {
        int rc;
 

+       if (client->remote_closed)
+               return -1;
+

        rc = pb_protocol_write_message(client->fd, message);
        if (rc)
        rc = pb_protocol_write_message(client->fd, message);
        if (rc)

-               talloc_free(client);
+               client->remote_closed = true;

 
        return rc;
 }
 
        return rc;
 }


@@ -250,6 +254,9 @@ static int discover_server_process_connection(void *arg)
 
        client->fd = fd;
        client->server = server;
 
        client->fd = fd;
        client->server = server;

+       client->waiter = waiter_register_io(server->waitset, client->fd,
+                               WAIT_IN, discover_server_process_message,
+                               client);

 
        /* send sysinfo to client */
        rc = write_system_info_message(server, client, system_info_get());
 
        /* send sysinfo to client */
        rc = write_system_info_message(server, client, system_info_get());


@@ -275,10 +282,6 @@ static int discover_server_process_connection(void *arg)
                }
        }
 
                }
        }
 

-       client->waiter = waiter_register_io(server->waitset, client->fd,
-                               WAIT_IN, discover_server_process_message,
-                               client);
-

        return 0;
 }
 
        return 0;
 }