source: vendor/current/ctdb/tcp/tcp_init.c

/* 
   ctdb over TCP

   Copyright (C) Andrew Tridgell  2006

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, see <http://www.gnu.org/licenses/>.
*/

#include "replace.h"
#include "system/network.h"
#include "system/filesys.h"

#include <talloc.h>
#include <tevent.h>

#include "lib/util/time.h"
#include "lib/util/debug.h"

#include "ctdb_private.h"

#include "common/common.h"
#include "common/logging.h"

#include "ctdb_tcp.h"

static int tnode_destructor(struct ctdb_tcp_node *tnode)
{
  //    struct ctdb_node *node = talloc_find_parent_bytype(tnode, struct ctdb_node);

        if (tnode->fd != -1) {
                close(tnode->fd);
                tnode->fd = -1;
        }

        return 0;
}

/*
  initialise tcp portion of a ctdb node 
*/
static int ctdb_tcp_add_node(struct ctdb_node *node)
{
        struct ctdb_tcp_node *tnode;
        tnode = talloc_zero(node, struct ctdb_tcp_node);
        CTDB_NO_MEMORY(node->ctdb, tnode);

        tnode->fd = -1;
        node->private_data = tnode;
        talloc_set_destructor(tnode, tnode_destructor);

        tnode->out_queue = ctdb_queue_setup(node->ctdb, node, tnode->fd, CTDB_TCP_ALIGNMENT,
                                            ctdb_tcp_tnode_cb, node, "to-node-%s", node->name);
        
        return 0;
}

/*
  initialise transport structures
*/
static int ctdb_tcp_initialise(struct ctdb_context *ctdb)
{
        int i;

        /* listen on our own address */
        if (ctdb_tcp_listen(ctdb) != 0) {
                DEBUG(DEBUG_CRIT, (__location__ " Failed to start listening on the CTDB socket\n"));
                exit(1);
        }

        for (i=0; i < ctdb->num_nodes; i++) {
                if (ctdb->nodes[i]->flags & NODE_FLAGS_DELETED) {
                        continue;
                }
                if (ctdb_tcp_add_node(ctdb->nodes[i]) != 0) {
                        DEBUG(DEBUG_CRIT, ("methods->add_node failed at %d\n", i));
                        return -1;
                }
        }
        
        return 0;
}

/*
  start the protocol going
*/
static int ctdb_tcp_connect_node(struct ctdb_node *node)
{
        struct ctdb_context *ctdb = node->ctdb;
        struct ctdb_tcp_node *tnode = talloc_get_type(
                node->private_data, struct ctdb_tcp_node);

        /* startup connection to the other server - will happen on
           next event loop */
        if (!ctdb_same_address(ctdb->address, &node->address)) {
                tnode->connect_te = tevent_add_timer(ctdb->ev, tnode,
                                                    timeval_zero(),
                                                    ctdb_tcp_node_connect,
                                                    node);
        }

        return 0;
}

/*
  shutdown and try to restart a connection to a node after it has been
  disconnected
*/
static void ctdb_tcp_restart(struct ctdb_node *node)
{
        struct ctdb_tcp_node *tnode = talloc_get_type(
                node->private_data, struct ctdb_tcp_node);

        DEBUG(DEBUG_NOTICE,("Tearing down connection to dead node :%d\n", node->pnn));

        ctdb_tcp_stop_connection(node);

        tnode->connect_te = tevent_add_timer(node->ctdb->ev, tnode,
                                             timeval_zero(),
                                             ctdb_tcp_node_connect, node);
}


/*
  shutdown the transport
*/
static void ctdb_tcp_shutdown(struct ctdb_context *ctdb)
{
        struct ctdb_tcp *ctcp = talloc_get_type(ctdb->private_data,
                                                struct ctdb_tcp);
        talloc_free(ctcp);
        ctdb->private_data = NULL;
}

/*
  start the transport
*/
static int ctdb_tcp_start(struct ctdb_context *ctdb)
{
        int i;

        for (i=0; i < ctdb->num_nodes; i++) {
                if (ctdb->nodes[i]->flags & NODE_FLAGS_DELETED) {
                        continue;
                }
                ctdb_tcp_connect_node(ctdb->nodes[i]);
        }

        return 0;
}


/*
  transport packet allocator - allows transport to control memory for packets
*/
static void *ctdb_tcp_allocate_pkt(TALLOC_CTX *mem_ctx, size_t size)
{
        /* tcp transport needs to round to 8 byte alignment to ensure
           that we can use a length header and 64 bit elements in
           structures */
        size = (size+(CTDB_TCP_ALIGNMENT-1)) & ~(CTDB_TCP_ALIGNMENT-1);
        return talloc_size(mem_ctx, size);
}


static const struct ctdb_methods ctdb_tcp_methods = {
        .initialise   = ctdb_tcp_initialise,
        .start        = ctdb_tcp_start,
        .queue_pkt    = ctdb_tcp_queue_pkt,
        .add_node     = ctdb_tcp_add_node,
        .connect_node = ctdb_tcp_connect_node,
        .allocate_pkt = ctdb_tcp_allocate_pkt,
        .shutdown     = ctdb_tcp_shutdown,
        .restart      = ctdb_tcp_restart,
};

static int tcp_ctcp_destructor(struct ctdb_tcp *ctcp)
{
        ctcp->ctdb->private_data = NULL;
        ctcp->ctdb->methods = NULL;
        
        return 0;
}

                
/*
  initialise tcp portion of ctdb 
*/
int ctdb_tcp_init(struct ctdb_context *ctdb)
{
        struct ctdb_tcp *ctcp;
        ctcp = talloc_zero(ctdb, struct ctdb_tcp);
        CTDB_NO_MEMORY(ctdb, ctcp);

        ctcp->listen_fd = -1;
        ctcp->ctdb      = ctdb;
        ctdb->private_data = ctcp;
        ctdb->methods = &ctdb_tcp_methods;

        talloc_set_destructor(ctcp, tcp_ctcp_destructor);
        return 0;
}