/****************************************************************************
* net/local/local_connnect.c
*
* Copyright (C) 2015-2017 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <string.h>
#include <unistd.h>
#include <assert.h>
#include <errno.h>
#include <queue.h>
#include <debug.h>
#include <nuttx/semaphore.h>
#include <nuttx/net/net.h>
#include <arch/irq.h>
#include "utils/utils.h"
#include "socket/socket.h"
#include "local/local.h"
#ifdef CONFIG_NET_LOCAL_STREAM
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: local_generate_instance_id
****************************************************************************/
static int32_t local_generate_instance_id(void)
{
static int32_t g_next_instance_id = 0;
int32_t id;
/* Called from local_connect with net_lock held. */
id = g_next_instance_id++;
if (g_next_instance_id < 0)
{
g_next_instance_id = 0;
}
return id;
}
/****************************************************************************
* Name: _local_semtake() and _local_semgive()
*
* Description:
* Take/give semaphore
*
****************************************************************************/
static inline void _local_semtake(sem_t *sem)
{
int ret;
do
{
/* Take the semaphore (perhaps waiting) */
ret = nxsem_wait(sem);
/* The only case that an error should occur here is if the wait was
* awakened by a signal.
*/
DEBUGASSERT(ret == OK || ret == -EINTR);
}
while (ret == -EINTR);
}
#define _local_semgive(sem) nxsem_post(sem)
/****************************************************************************
* Name: local_stream_connect
*
* Description:
* Find a local connection structure that is the appropriate "server"
* connection to be used with the provided "client" connection.
*
* Returned Value:
* Zero (OK) returned on success; A negated errno value is returned on a
* failure. Possible failures include:
*
* Assumptions:
* The network is locked on entry, unlocked on return. This logic is
* an integral part of the lock_connect() implementation and was
* separated out only to improve readability.
*
****************************************************************************/
static int inline local_stream_connect(FAR struct local_conn_s *client,
FAR struct local_conn_s *server,
bool nonblock)
{
int ret;
int sval;
/* Has server backlog been reached?
* NOTE: The backlog will be zero if listen() has never been called by the
* server.
*/
if (server->lc_state != LOCAL_STATE_LISTENING ||
server->u.server.lc_pending >= server->u.server.lc_backlog)
{
net_unlock();
nerr("ERROR: Server is not listening: lc_state=%d\n",
server->lc_state);
nerr(" OR: The backlog limit was reached: %d or %d\n",
server->u.server.lc_pending, server->u.server.lc_backlog);
return -ECONNREFUSED;
}
/* Increment the number of pending server connection s */
server->u.server.lc_pending++;
DEBUGASSERT(server->u.server.lc_pending != 0);
/* Create the FIFOs needed for the connection */
ret = local_create_fifos(client);
if (ret < 0)
{
nerr("ERROR: Failed to create FIFOs for %s: %d\n",
client->lc_path, ret);
net_unlock();
return ret;
}
/* Open the client-side write-only FIFO. This should not block and should
* prevent the server-side from blocking as well.
*/
ret = local_open_client_tx(client, nonblock);
if (ret < 0)
{
nerr("ERROR: Failed to open write-only FIFOs for %s: %d\n",
client->lc_path, ret);
net_unlock();
goto errout_with_fifos;
}
DEBUGASSERT(client->lc_outfile.f_inode != NULL);
/* Add ourself to the list of waiting connections and notify the server. */
dq_addlast(&client->lc_node, &server->u.server.lc_waiters);
client->lc_state = LOCAL_STATE_ACCEPT;
local_accept_pollnotify(server, POLLIN);
if (nxsem_getvalue(&server->lc_waitsem, &sval) >= 0 && sval < 1)
{
_local_semgive(&server->lc_waitsem);
}
net_unlock();
/* Wait for the server to accept the connections */
client->u.client.lc_result = -EBUSY;
do
{
_local_semtake(&client->lc_waitsem);
ret = client->u.client.lc_result;
}
while (ret == -EBUSY);
/* Did we successfully connect? */
if (ret < 0)
{
nerr("ERROR: Failed to connect: %d\n", ret);
goto errout_with_outfd;
}
/* Yes.. open the read-only FIFO */
ret = local_open_client_rx(client, nonblock);
if (ret < 0)
{
nerr("ERROR: Failed to open write-only FIFOs for %s: %d\n",
client->lc_path, ret);
goto errout_with_outfd;
}
DEBUGASSERT(client->lc_infile.f_inode != NULL);
client->lc_state = LOCAL_STATE_CONNECTED;
return OK;
errout_with_outfd:
(void)file_close_detached(&client->lc_outfile);
client->lc_outfile.f_inode = NULL;
errout_with_fifos:
(void)local_release_fifos(client);
client->lc_state = LOCAL_STATE_BOUND;
return ret;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: psock_local_connect
*
* Description:
* Find a local connection structure that is the appropriate "server"
* connection to be used with the provided "client" connection.
*
* Returned Value:
* Zero (OK) returned on success; A negated errno value is returned on a
* failure. Possible failures include:
*
* EISCONN - The specified socket is connection-mode and is already
* connected.
* EADDRNOTAVAIL - The specified address is not available from the
* local machine.
* ECONNREFUSED - The target address was not listening for connections or
* refused the connection request because the connection backlog has
* been exceeded.
*
****************************************************************************/
int psock_local_connect(FAR struct socket *psock,
FAR const struct sockaddr *addr)
{
FAR struct local_conn_s *client;
FAR struct sockaddr_un *unaddr = (FAR struct sockaddr_un *)addr;
FAR struct local_conn_s *conn;
DEBUGASSERT(psock && psock->s_conn);
client = (FAR struct local_conn_s *)psock->s_conn;
if (client->lc_state == LOCAL_STATE_ACCEPT ||
client->lc_state == LOCAL_STATE_CONNECTED)
{
return -EISCONN;
}
/* Find the matching server connection */
net_lock();
for (conn = (FAR struct local_conn_s *)g_local_listeners.head;
conn;
conn = (FAR struct local_conn_s *)dq_next(&conn->lc_node))
{
/* Anything in the listener list should be a stream socket in the
* istening state
*/
DEBUGASSERT(conn->lc_state == LOCAL_STATE_LISTENING &&
conn->lc_proto == SOCK_STREAM);
/* Handle according to the server connection type */
switch (conn->lc_type)
{
case LOCAL_TYPE_UNNAMED: /* A Unix socket that is not bound to any name */
case LOCAL_TYPE_ABSTRACT: /* lc_path is length zero */
{
#warning Missing logic
net_unlock();
return OK;
}
break;
case LOCAL_TYPE_PATHNAME: /* lc_path holds a null terminated string */
{
if (strncmp(conn->lc_path, unaddr->sun_path, UNIX_PATH_MAX-1) == 0)
{
int ret = OK;
/* Bind the address and protocol */
client->lc_proto = conn->lc_proto;
strncpy(client->lc_path, unaddr->sun_path, UNIX_PATH_MAX-1);
client->lc_path[UNIX_PATH_MAX-1] = '\0';
client->lc_instance_id = local_generate_instance_id();
/* The client is now bound to an address */
client->lc_state = LOCAL_STATE_BOUND;
/* We have to do more for the SOCK_STREAM family */
if (conn->lc_proto == SOCK_STREAM)
{
ret = local_stream_connect(client, conn,
_SS_ISNONBLOCK(psock->s_flags));
}
else
{
net_unlock();
}
return ret;
}
}
break;
default: /* Bad, memory must be corrupted */
DEBUGPANIC(); /* PANIC if debug on, else fall through */
case LOCAL_TYPE_UNTYPED: /* Type is not determined until the socket is bound */
{
net_unlock();
return -EINVAL;
}
}
}
net_unlock();
return -EADDRNOTAVAIL;
}
#endif /* CONFIG_NET_LOCAL_STREAM */