incubator-nuttx/net/can/can_sockif.c

520 lines
14 KiB
C

/****************************************************************************
* net/can/can_sockif.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <stdbool.h>
#include <string.h>
#include <poll.h>
#include <sched.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/kmalloc.h>
#include <nuttx/semaphore.h>
#include <nuttx/wqueue.h>
#include <nuttx/net/net.h>
#include "can/can.h"
#include "netdev/netdev.h"
#ifdef CONFIG_NET_CAN
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static int can_setup(FAR struct socket *psock);
static sockcaps_t can_sockcaps(FAR struct socket *psock);
static void can_addref(FAR struct socket *psock);
static int can_bind(FAR struct socket *psock,
FAR const struct sockaddr *addr, socklen_t addrlen);
static int can_poll_local(FAR struct socket *psock, FAR struct pollfd *fds,
bool setup);
static int can_close(FAR struct socket *psock);
/****************************************************************************
* Public Data
****************************************************************************/
const struct sock_intf_s g_can_sockif =
{
can_setup, /* si_setup */
can_sockcaps, /* si_sockcaps */
can_addref, /* si_addref */
can_bind, /* si_bind */
NULL, /* si_getsockname */
NULL, /* si_getpeername */
NULL, /* si_listen */
NULL, /* si_connect */
NULL, /* si_accept */
can_poll_local, /* si_poll */
can_sendmsg, /* si_sendmsg */
can_recvmsg, /* si_recvmsg */
can_close, /* si_close */
NULL, /* si_ioctl */
NULL, /* si_socketpair */
NULL /* si_shutdown */
#if defined(CONFIG_NET_SOCKOPTS) && defined(CONFIG_NET_CANPROTO_OPTIONS)
, can_getsockopt /* si_getsockopt */
, can_setsockopt /* si_setsockopt */
#endif
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: can_poll_eventhandler
*
* Description:
* This function is called to perform the actual CAN receive operation
* via the device interface layer. from can_input()
*
* Input Parameters:
* dev The structure of the network driver that caused the event
* pvpriv An instance of struct can_poll_s cast to void*
* flags Set of events describing why the callback was invoked
*
* Returned Value:
* None
*
* Assumptions:
* This function must be called with the network locked.
*
****************************************************************************/
static uint16_t can_poll_eventhandler(FAR struct net_driver_s *dev,
FAR void *pvpriv, uint16_t flags)
{
FAR struct can_poll_s *info = pvpriv;
DEBUGASSERT(!info || (info->psock && info->fds));
/* 'priv' might be null in some race conditions (?) */
if (info)
{
pollevent_t eventset = 0;
/* Check for data or connection availability events. */
if ((flags & CAN_NEWDATA) != 0)
{
eventset |= POLLIN;
}
/* Check for loss of connection events. */
if ((flags & NETDEV_DOWN) != 0)
{
eventset |= (POLLHUP | POLLERR);
}
/* A poll is a sign that we are free to send data. */
else if ((flags & CAN_POLL) != 0 &&
psock_can_cansend(info->psock) >= 0)
{
eventset |= POLLOUT;
}
/* Awaken the caller of poll() is requested event occurred. */
poll_notify(&info->fds, 1, eventset);
}
return flags;
}
/****************************************************************************
* Name: can_setup
*
* Description:
* Called for socket() to verify that the provided socket type and
* protocol are usable by this address family. Perform any family-
* specific socket fields.
*
* Input Parameters:
* psock - A pointer to a user allocated socket structure to be
* initialized.
*
* Returned Value:
* Zero (OK) is returned on success. Otherwise, a negated errno value is
* returned.
*
****************************************************************************/
static int can_setup(FAR struct socket *psock)
{
int domain = psock->s_domain;
int type = psock->s_type;
int proto = psock->s_proto;
/* Verify that the protocol is supported */
DEBUGASSERT((unsigned int)proto <= UINT8_MAX);
switch (proto)
{
case 0: /* INET subsystem for netlib_ifup */
case CAN_RAW: /* RAW sockets */
case CAN_BCM: /* Broadcast Manager */
case CAN_TP16: /* VAG Transport Protocol v1.6 */
case CAN_TP20: /* VAG Transport Protocol v2.0 */
case CAN_MCNET: /* Bosch MCNet */
case CAN_ISOTP: /* ISO 15765-2 Transport Protocol */
case CAN_J1939: /* SAE J1939 */
break;
default:
return -EPROTONOSUPPORT;
}
/* Verify the socket type (domain should always be PF_CAN here) */
if (domain == PF_CAN &&
(type == SOCK_RAW || type == SOCK_DGRAM || type == SOCK_CTRL))
{
/* Allocate the CAN socket connection structure and save it in the
* new socket instance.
*/
FAR struct can_conn_s *conn = can_alloc();
if (conn == NULL)
{
/* Failed to reserve a connection structure */
return -ENOMEM;
}
/* Set the reference count on the connection structure. This
* reference count will be incremented only if the socket is
* dup'ed
*/
conn->crefs = 1;
/* Attach the connection instance to the socket */
psock->s_conn = conn;
return OK;
}
return -EPROTONOSUPPORT;
}
/****************************************************************************
* Name: can_sockcaps
*
* Description:
* Return the bit encoded capabilities of this socket.
*
* Input Parameters:
* psock - Socket structure of the socket whose capabilities are being
* queried.
*
* Returned Value:
* The non-negative set of socket capabilities is returned.
*
****************************************************************************/
static sockcaps_t can_sockcaps(FAR struct socket *psock)
{
/* Permit vfcntl to set socket to non-blocking */
return SOCKCAP_NONBLOCKING;
}
/****************************************************************************
* Name: can_addref
*
* Description:
* Increment the reference count on the underlying connection structure.
*
* Input Parameters:
* psock - Socket structure of the socket whose reference count will be
* incremented.
*
* Returned Value:
* None
*
****************************************************************************/
static void can_addref(FAR struct socket *psock)
{
FAR struct can_conn_s *conn;
conn = psock->s_conn;
DEBUGASSERT(conn->crefs > 0 && conn->crefs < 255);
conn->crefs++;
}
/****************************************************************************
* Name: can_bind
*
* Description:
* can_bind() gives the socket 'conn' the local address 'addr'. 'addr'
* is 'addrlen' bytes long. Traditionally, this is called "assigning a name
* to a socket." When a socket is created with socket, it exists in a name
* space (address family) but has no name assigned.
*
* Input Parameters:
* conn CAN socket connection structure
* addr Socket local address
* addrlen Length of 'addr'
*
* Returned Value:
* 0 on success; -1 on error with errno set appropriately
*
* EACCES
* The address is protected, and the user is not the superuser.
* EADDRINUSE
* The given address is already in use.
* EINVAL
* The socket is already bound to an address.
* ENOTSOCK
* psock is a descriptor for a file, not a socket.
*
* Assumptions:
*
****************************************************************************/
static int can_bind(FAR struct socket *psock,
FAR const struct sockaddr *addr, socklen_t addrlen)
{
FAR struct sockaddr_can *canaddr;
FAR struct can_conn_s *conn;
DEBUGASSERT(addr != NULL &&
addrlen >= sizeof(struct sockaddr_can));
/* Save the address information in the connection structure */
canaddr = (FAR struct sockaddr_can *)addr;
conn = psock->s_conn;
/* Bind CAN device to socket */
#ifdef CONFIG_NETDEV_IFINDEX
conn->dev = netdev_findbyindex(canaddr->can_ifindex);
#else
char netdev_name[5] = "can0";
netdev_name[3] += canaddr->can_ifindex;
conn->dev = netdev_findbyname((const char *)&netdev_name);
#endif
return OK;
}
/****************************************************************************
* Name: can_poll_local
*
* Description:
* The standard poll() operation redirects operations on socket descriptors
* to this function.
*
* POLLUP: Will never be reported
* POLLERR: Reported in the event of any failure.
* POLLOUT: Always reported if requested.
* POLLIN: Reported if requested but only when pending response data is
* available
*
* Input Parameters:
* psock - An instance of the internal socket structure.
* fds - The structure describing the events to be monitored.
* setup - true: Setup up the poll; false: Tear down the poll
*
* Returned Value:
* 0: Success; Negated errno on failure
*
****************************************************************************/
static int can_poll_local(FAR struct socket *psock, FAR struct pollfd *fds,
bool setup)
{
FAR struct can_conn_s *conn;
FAR struct can_poll_s *info;
FAR struct devif_callback_s *cb;
pollevent_t eventset = 0;
int ret = OK;
conn = psock->s_conn;
info = conn->pollinfo;
/* FIXME add NETDEV_DOWN support */
/* Check if we are setting up or tearing down the poll */
if (setup)
{
net_lock();
info->dev = conn->dev;
cb = can_callback_alloc(info->dev, conn);
if (cb == NULL)
{
ret = -EBUSY;
goto errout_with_lock;
}
/* Initialize the poll info container */
info->psock = psock;
info->fds = fds;
info->cb = cb;
/* Initialize the callback structure. Save the reference to the info
* structure as callback private data so that it will be available
* during callback processing.
*/
cb->flags = NETDEV_DOWN;
cb->priv = info;
cb->event = can_poll_eventhandler;
if ((fds->events & POLLOUT) != 0)
{
cb->flags |= CAN_POLL;
}
if ((fds->events & POLLIN) != 0)
{
cb->flags |= CAN_NEWDATA;
}
/* Save the reference in the poll info structure as fds private as well
* for use during poll teardown as well.
*/
fds->priv = info;
/* Check for read data availability now */
if (!IOB_QEMPTY(&conn->readahead))
{
/* Normal data may be read without blocking. */
eventset |= POLLRDNORM;
}
if (psock_can_cansend(psock) >= 0)
{
/* A CAN frame may be sent without blocking. */
eventset |= POLLWRNORM;
}
/* Check if any requested events are already in effect */
poll_notify(&fds, 1, eventset);
errout_with_lock:
net_unlock();
}
else
{
info = (FAR struct can_poll_s *)fds->priv;
if (info != NULL)
{
/* Cancel any response notifications */
can_callback_free(info->dev, conn, info->cb);
/* Release the poll/select data slot */
info->fds->priv = NULL;
/* Then free the poll info container */
info->psock = NULL;
}
}
return ret;
}
/****************************************************************************
* Name: can_close
*
* Description:
* Performs the close operation on a CAN socket instance
*
* Input Parameters:
* psock Socket instance
*
* Returned Value:
* 0 on success; -1 on error with errno set appropriately.
*
* Assumptions:
*
****************************************************************************/
static int can_close(FAR struct socket *psock)
{
FAR struct can_conn_s *conn = psock->s_conn;
int ret = OK;
/* Perform some pre-close operations for the CAN socket type. */
/* Is this the last reference to the connection structure (there
* could be more if the socket was dup'ed).
*/
if (conn->crefs <= 1)
{
/* Yes... inform user-space daemon of socket close. */
/* #warning Missing logic */
/* Free the connection structure */
conn->crefs = 0;
can_free(psock->s_conn);
if (ret < 0)
{
/* Return with error code, but free resources. */
nerr("ERROR: can_close failed: %d\n", ret);
return ret;
}
}
else
{
/* No.. Just decrement the reference count */
conn->crefs--;
}
return ret;
}
#endif /* CONFIG_NET_CAN */