incubator-nuttx/net/local/local_accept.c

260 lines
8.1 KiB
C

/****************************************************************************
* net/local/local_accept.c
*
* Copyright (C) 2015 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>
#if defined(CONFIG_NET) && defined(CONFIG_NET_LOCAL_STREAM)
#include <string.h>
#include <errno.h>
#include <assert.h>
#include <queue.h>
#include <debug.h>
#include <nuttx/net/net.h>
#include "socket/socket.h"
#include "local/local.h"
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Function: local_waitlisten
****************************************************************************/
static int local_waitlisten(FAR struct local_conn_s *server)
{
int ret;
/* Loop until a connection is requested or we receive a signal */
while (dq_empty(&server->u.server.lc_waiters))
{
/* No.. wait for a connection or a signal */
ret = sem_wait(&server->lc_waitsem);
if (ret < 0)
{
int errval = get_errno();
DEBUGASSERT(errval == EINTR);
return -errval;
}
}
/* There is a client waiting for the connection */
return OK;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Function: psock_local_accept
*
* Description:
* This function implements accept() for Unix domain sockets. See the
* description of accept() for further information.
*
* Parameters:
* psock The listening Unix domain socket structure
* addr Receives the address of the connecting client
* addrlen Input: allocated size of 'addr', Return: returned size of 'addr'
* newconn The new, accepted Unix domain connection structure
*
* Returned Value:
* Returns zero (OK) on success or a negated errno value on failure.
* See the description of accept of the possible errno values in the
* description of accept().
*
* Assumptions:
* Network is NOT locked.
*
****************************************************************************/
int psock_local_accept(FAR struct socket *psock, FAR struct sockaddr *addr,
FAR socklen_t *addrlen, FAR void **newconn)
{
FAR struct local_conn_s *server;
FAR struct local_conn_s *client;
FAR struct local_conn_s *conn;
int ret;
/* Some sanity checks */
DEBUGASSERT(psock && psock->s_conn);
server = (FAR struct local_conn_s *)psock->s_conn;
if (server->lc_proto != SOCK_STREAM ||
server->lc_state != LOCAL_STATE_LISTENING ||
server->lc_type != LOCAL_TYPE_PATHNAME)
{
return -EOPNOTSUPP;
}
/* Loop as necessary if we have to wait for a connection */
for (;;)
{
/* Are there pending connections. Remove the client from the
* head of the waiting list.
*/
client = (FAR struct local_conn_s *)
dq_remfirst(&server->u.server.lc_waiters);
if (client)
{
/* Decrement the number of pending clients */
DEBUGASSERT(server->u.server.lc_pending > 0);
server->u.server.lc_pending--;
/* Create a new connection structure for the server side of the
* connection.
*/
conn = local_alloc();
if (!conn)
{
ndbg("ERROR: Failed to allocate new connection structure\n");
ret = -ENOMEM;
}
else
{
/* Initialize the new connection structure */
conn->lc_crefs = 1;
conn->lc_proto = SOCK_STREAM;
conn->lc_type = LOCAL_TYPE_PATHNAME;
conn->lc_state = LOCAL_STATE_CONNECTED;
strncpy(conn->lc_path, client->lc_path, UNIX_PATH_MAX-1);
conn->lc_path[UNIX_PATH_MAX-1] = '\0';
conn->lc_instance_id = client->lc_instance_id;
/* Open the server-side write-only FIFO. This should not
* block.
*/
ret = local_open_server_tx(conn,
_SS_ISNONBLOCK(psock->s_flags));
if (ret < 0)
{
ndbg("ERROR: Failed to open write-only FIFOs for %s: %d\n",
conn->lc_path, ret);
}
}
/* Do we have a connection? Is the write-side FIFO opened? */
if (ret == OK)
{
DEBUGASSERT(conn->lc_outfd >= 0);
/* Open the server-side read-only FIFO. This should not
* block because the client side has already opening it
* for writing.
*/
ret = local_open_server_rx(conn,
_SS_ISNONBLOCK(psock->s_flags));
if (ret < 0)
{
ndbg("ERROR: Failed to open read-only FIFOs for %s: %d\n",
conn->lc_path, ret);
}
}
/* Do we have a connection? Are the FIFOs opened? */
if (ret == OK)
{
DEBUGASSERT(conn->lc_infd >= 0);
/* Return the address family */
if (addr)
{
ret = local_getaddr(client, addr, addrlen);
}
}
if (ret == OK)
{
/* Return the client connection structure */
*newconn = (FAR void *)conn;
}
/* Signal the client with the result of the connection */
client->u.client.lc_result = ret;
sem_post(&client->lc_waitsem);
return ret;
}
/* No.. then there should be no pending connections */
DEBUGASSERT(server->u.server.lc_pending == 0);
/* Was the socket opened non-blocking? */
if (_SS_ISNONBLOCK(psock->s_flags))
{
/* Yes.. return EAGAIN */
return -EAGAIN;
}
/* Otherwise, listen for a connection and try again. */
ret = local_waitlisten(server);
if (ret < 0)
{
return ret;
}
}
}
#endif /* CONFIG_NET && CONFIG_NET_LOCAL_STREAM */