/*
* initialize connection pools. this should be called once at the startup.
*/
int pool_init_cp(void)
{
int i;
pool_connection_pool = (POOL_CONNECTION_POOL *)malloc(sizeof(POOL_CONNECTION_POOL)*pool_config->max_pool);
if (pool_connection_pool == NULL)
{
pool_error("pool_init_cp: malloc() failed");
return -1;
}
memset(pool_connection_pool, 0, sizeof(POOL_CONNECTION_POOL)*pool_config->max_pool);
for (i = 0; i < pool_config->max_pool; i++)
{
pool_connection_pool[i].info = pool_coninfo(pool_get_process_context()->proc_id, i, 0);
memset(pool_connection_pool[i].info, 0, sizeof(ConnectionInfo) * MAX_NUM_BACKENDS);
}
return 0;
}
/*
* Unset frontend connected flag
*/
void pool_coninfo_unset_frontend_connected(int proc_id, int pool_index)
{
ConnectionInfo *con;
int i;
for (i=0;i<NUM_BACKENDS;i++)
{
if (!VALID_BACKEND(i))
continue;
con = pool_coninfo(proc_id, pool_index, i);
if (con == NULL)
{
elog(WARNING,"failed to get connection info while marking the frontend is not connected for pool");
return;
}
con->connected = false;
}
}
/*
* process cancel request
*/
void cancel_request(CancelPacket *sp)
{
int len;
int fd;
POOL_CONNECTION *con;
int i,j,k;
ConnectionInfo *c = NULL;
CancelPacket cp;
bool found = false;
pool_debug("Cancel request received");
/* look for cancel key from shmem info */
for (i=0;i<pool_config->num_init_children;i++)
{
for (j=0;j<pool_config->max_pool;j++)
{
for (k=0;k<NUM_BACKENDS;k++)
{
c = pool_coninfo(i, j, k);
pool_debug("con_info: address:%p database:%s user:%s pid:%d key:%d i:%d",
c, c->database, c->user, ntohl(c->pid), ntohl(c->key),i);
if (c->pid == sp->pid && c->key == sp->key)
{
pool_debug("found pid:%d key:%d i:%d",ntohl(c->pid), ntohl(c->key),i);
c = pool_coninfo(i, j, 0);
found = true;
goto found;
}
}
}
}
found:
if (!found)
{
pool_error("cancel_request: invalid cancel key: pid:%d key:%d",ntohl(sp->pid), ntohl(sp->key));
return; /* invalid key */
}
for (i=0;i<NUM_BACKENDS;i++,c++)
{
if (!VALID_BACKEND(i))
continue;
if (*(BACKEND_INFO(i).backend_hostname) == '/')
fd = connect_unix_domain_socket(i, TRUE);
else
fd = connect_inet_domain_socket(i, TRUE);
if (fd < 0)
{
pool_error("Could not create socket for sending cancel request for backend %d", i);
return;
}
con = pool_open(fd);
if (con == NULL)
return;
len = htonl(sizeof(len) + sizeof(CancelPacket));
pool_write(con, &len, sizeof(len));
cp.protoVersion = sp->protoVersion;
cp.pid = c->pid;
cp.key = c->key;
pool_log("cancel_request: canceling backend pid:%d key: %d", ntohl(cp.pid),ntohl(cp.key));
if (pool_write_and_flush(con, &cp, sizeof(CancelPacket)) < 0)
pool_error("Could not send cancel request packet for backend %d", i);
pool_close(con);
/*
* this is needed to ensure that the next DB node executes the
* query supposed to be canceled.
*/
sleep(1);
}
}
