/*
* Discard connection and memory allocated by
* make_persistent_db_connection().
*/
void discard_persistent_db_connection(POOL_CONNECTION_POOL_SLOT *cp)
{
int len;
if(cp == NULL)
return;
pool_write(cp->con, "X", 1);
len = htonl(4);
pool_write(cp->con, &len, sizeof(len));
/*
* XXX we cannot call pool_flush() here since backend may already
* close the socket and pool_flush() automatically invokes fail
* over handler. This could happen in copy command (remember the
* famous "lost synchronization with server, resetting
* connection" message)
*/
pool_set_nonblock(cp->con->fd);
pool_flush_it(cp->con);
pool_unset_nonblock(cp->con->fd);
pool_close(cp->con);
free(cp->sp->startup_packet);
free(cp->sp->database);
free(cp->sp->user);
free(cp->sp);
free(cp);
}
/*
* flush write buffer and degenerate/failover if error occurs
*/
int pool_flush(POOL_CONNECTION *cp)
{
if (pool_flush_it(cp) == -1)
{
if (cp->isbackend)
{
/* if fail_over_on_backend_erro is true, then trigger failover */
if (pool_config->fail_over_on_backend_error)
{
notice_backend_error(cp->db_node_id);
child_exit(1);
}
else
return -1;
}
else
{
/*
* ignore error on frontend. we need to continue the
* processing with backends
*/
return 0;
}
}
return 0;
}
/*
* flush write buffer and degenerate/failover if error occurs
*/
int pool_flush(POOL_CONNECTION *cp)
{
if (pool_flush_it(cp) == -1)
{
if (cp->isbackend)
{
/* if fail_over_on_backend_erro is true, then trigger failover */
if (pool_config->fail_over_on_backend_error)
{
notice_backend_error(cp->db_node_id);
child_exit(1);
}
else
return -1;
}
else
{
/*
* If we are in replication mode, we need to continue the
* processing with backends to keep consistency among
* backends, thus ignore error.
*/
if (REPLICATION)
return 0;
else
return -1;
}
}
return 0;
}
/*
* write len bytes to cp the write buffer.
* returns 0 on success otherwise -1.
*/
int pool_write(POOL_CONNECTION *cp, void *buf, int len)
{
if (len < 0)
{
pool_error("pool_write: invalid request size: %d", len);
return -1;
}
if (cp->no_forward)
return 0;
while (len > 0)
{
int remainder = WRITEBUFSZ - cp->wbufpo;
if (cp->wbufpo >= WRITEBUFSZ)
{
/*
* Write buffer is full. so flush buffer.
* wbufpo is reset in pool_flush_it().
*/
if (pool_flush_it(cp) == -1)
return -1;
remainder = WRITEBUFSZ;
}
/* check buffer size */
if (remainder >= len)
{
/* OK, buffer size is enough. */
remainder = len;
}
memcpy(cp->wbuf+cp->wbufpo, buf, remainder);
cp->wbufpo += remainder;
buf += remainder;
len -= remainder;
}
return 0;
}
