nuttx/net/pkt/pkt_recvfrom.c
Xiang Xiao 6a3c2aded6 Fix wait loop and void cast (#24)
* Simplify EINTR/ECANCEL error handling

1. Add semaphore uninterruptible wait function
2 .Replace semaphore wait loop with a single uninterruptible wait
3. Replace all sem_xxx to nxsem_xxx

* Unify the void cast usage

1. Remove void cast for function because many place ignore the returned value witout cast
2. Replace void cast for variable with UNUSED macro
2020-01-02 10:54:43 -06:00

447 lines
13 KiB
C

/****************************************************************************
* net/pkt/pkt_recvfrom.c
*
* Copyright (C) 2007-2009, 2011-2017 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>
#ifdef CONFIG_NET
#include <sys/types.h>
#include <sys/socket.h>
#include <stdint.h>
#include <string.h>
#include <errno.h>
#include <debug.h>
#include <assert.h>
#include <arch/irq.h>
#include <nuttx/clock.h>
#include <nuttx/semaphore.h>
#include <nuttx/net/net.h>
#include <nuttx/net/netdev.h>
#include "netdev/netdev.h"
#include "devif/devif.h"
#include "pkt/pkt.h"
#include "socket/socket.h"
#include <netpacket/packet.h>
/****************************************************************************
* Private Types
****************************************************************************/
struct pkt_recvfrom_s
{
FAR struct devif_callback_s *pr_cb; /* Reference to callback instance */
sem_t pr_sem; /* Semaphore signals recv completion */
size_t pr_buflen; /* Length of receive buffer */
uint8_t *pr_buffer; /* Pointer to receive buffer */
ssize_t pr_recvlen; /* The received length */
int pr_result; /* Success:OK, failure:negated errno */
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: pkt_add_recvlen
*
* Description:
* Update information about space available for new data and update size
* of data in buffer, This logic accounts for the case where
* recvfrom_udpreadahead() sets state.pr_recvlen == -1 .
*
* Input Parameters:
* pstate recvfrom state structure
* recvlen size of new data appended to buffer
*
* Returned Value:
* None
*
****************************************************************************/
static inline void pkt_add_recvlen(FAR struct pkt_recvfrom_s *pstate,
size_t recvlen)
{
if (pstate->pr_recvlen < 0)
{
pstate->pr_recvlen = 0;
}
pstate->pr_recvlen += recvlen;
pstate->pr_buffer += recvlen;
pstate->pr_buflen -= recvlen;
}
/****************************************************************************
* Name: pkt_recvfrom_newdata
*
* Description:
* Copy the read data from the packet
*
* Input Parameters:
* dev The structure of the network driver that caused the event.
* pstate recvfrom state structure
*
* Returned Value:
* None.
*
* Assumptions:
* The network is locked.
*
****************************************************************************/
static void pkt_recvfrom_newdata(FAR struct net_driver_s *dev,
FAR struct pkt_recvfrom_s *pstate)
{
size_t recvlen;
if (dev->d_len > pstate->pr_buflen)
{
recvlen = pstate->pr_buflen;
}
else
{
recvlen = dev->d_len;
}
/* Copy the new packet data into the user buffer */
memcpy(pstate->pr_buffer, dev->d_buf, recvlen);
ninfo("Received %d bytes (of %d)\n", (int)recvlen, (int)dev->d_len);
/* Update the accumulated size of the data read */
pkt_add_recvlen(pstate, recvlen);
}
/****************************************************************************
* Name: pkt_recvfrom_sender
*
* Description:
*
* Input Parameters:
*
* Returned Value:
*
* Assumptions:
*
****************************************************************************/
static inline void pkt_recvfrom_sender(FAR struct net_driver_s *dev,
FAR struct pkt_recvfrom_s *pstate)
{
}
/****************************************************************************
* Name: pkt_recvfrom_eventhandler
*
* Description:
*
* Input Parameters:
*
* Returned Value:
*
* Assumptions:
*
****************************************************************************/
static uint16_t pkt_recvfrom_eventhandler(FAR struct net_driver_s *dev,
FAR void *pvconn,
FAR void *pvpriv, uint16_t flags)
{
struct pkt_recvfrom_s *pstate = (struct pkt_recvfrom_s *)pvpriv;
ninfo("flags: %04x\n", flags);
/* 'priv' might be null in some race conditions (?) */
if (pstate)
{
/* If a new packet is available, then complete the read action. */
if ((flags & PKT_NEWDATA) != 0)
{
/* Copy the packet */
pkt_recvfrom_newdata(dev, pstate);
/* We are finished. */
ninfo("PKT done\n");
/* Don't allow any further call backs. */
pstate->pr_cb->flags = 0;
pstate->pr_cb->priv = NULL;
pstate->pr_cb->event = NULL;
/* Save the sender's address in the caller's 'from' location */
pkt_recvfrom_sender(dev, pstate);
/* indicate that the data has been consumed */
flags &= ~PKT_NEWDATA;
/* Wake up the waiting thread, returning the number of bytes
* actually read.
*/
nxsem_post(&pstate->pr_sem);
}
}
return flags;
}
/****************************************************************************
* Name: pkt_recvfrom_initialize
*
* Description:
* Initialize the state structure
*
* Input Parameters:
* psock Pointer to the socket structure for the socket
* buf Buffer to receive data
* len Length of buffer
* pstate A pointer to the state structure to be initialized
*
* Returned Value:
* None
*
* Assumptions:
*
****************************************************************************/
static void pkt_recvfrom_initialize(FAR struct socket *psock, FAR void *buf,
size_t len, FAR struct sockaddr *infrom,
FAR socklen_t *fromlen,
FAR struct pkt_recvfrom_s *pstate)
{
/* Initialize the state structure. */
memset(pstate, 0, sizeof(struct pkt_recvfrom_s));
/* This semaphore is used for signaling and, hence, should not have
* priority inheritance enabled.
*/
nxsem_init(&pstate->pr_sem, 0, 0); /* Doesn't really fail */
nxsem_setprotocol(&pstate->pr_sem, SEM_PRIO_NONE);
pstate->pr_buflen = len;
pstate->pr_buffer = buf;
}
/* The only un-initialization that has to be performed is destroying the
* semaphore.
*/
#define pkt_recvfrom_uninitialize(s) nxsem_destroy(&(s)->pr_sem)
/****************************************************************************
* Name: pkt_recvfrom_result
*
* Description:
* Evaluate the result of the recv operations
*
* Input Parameters:
* result The result of the net_lockedwait operation (may indicate EINTR)
* pstate A pointer to the state structure to be initialized
*
* Returned Value:
* The result of the recv operation with errno set appropriately
*
* Assumptions:
*
****************************************************************************/
static ssize_t pkt_recvfrom_result(int result, struct pkt_recvfrom_s *pstate)
{
/* Check for a error/timeout detected by the event handler. Errors are
* signaled by negative errno values for the rcv length
*/
if (pstate->pr_result < 0)
{
/* This might return EAGAIN on a timeout or ENOTCONN on loss of
* connection (TCP only)
*/
return pstate->pr_result;
}
/* If net_lockedwait failed, then we were probably reawakened by a signal. In
* this case, net_lockedwait will have returned negated errno appropriately.
*/
if (result < 0)
{
return result;
}
return pstate->pr_recvlen;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: pkt_recvfrom
*
* Description:
* Implements the socket recvfrom interface for the case of the AF_INET
* and AF_INET6 address families. pkt_recvfrom() receives messages from
* a socket, and may be used to receive data on a socket whether or not it
* is connection-oriented.
*
* If 'from' is not NULL, and the underlying protocol provides the source
* address, this source address is filled in. The argument 'fromlen' is
* initialized to the size of the buffer associated with from, and
* modified on return to indicate the actual size of the address stored
* there.
*
* Input Parameters:
* psock A pointer to a NuttX-specific, internal socket structure
* buf Buffer to receive data
* len Length of buffer
* flags Receive flags
* from Address of source (may be NULL)
* fromlen The length of the address structure
*
* Returned Value:
* On success, returns the number of characters received. If no data is
* available to be received and the peer has performed an orderly shutdown,
* recv() will return 0. Otherwise, on errors, a negated errno value is
* returned (see recvfrom() for the list of appropriate error values).
*
****************************************************************************/
ssize_t pkt_recvfrom(FAR struct socket *psock, FAR void *buf, size_t len,
int flags, FAR struct sockaddr *from,
FAR socklen_t *fromlen)
{
FAR struct pkt_conn_s *conn = (FAR struct pkt_conn_s *)psock->s_conn;
FAR struct net_driver_s *dev;
struct pkt_recvfrom_s state;
ssize_t ret;
/* If a 'from' address has been provided, verify that it is large
* enough to hold this address family.
*/
if (from != NULL && *fromlen < sizeof(sa_family_t))
{
return -EINVAL;
}
if (psock->s_type != SOCK_RAW)
{
nerr("ERROR: Unsupported socket type: %d\n", psock->s_type);
ret = -ENOSYS;
}
/* Perform the packet recvfrom() operation */
/* Initialize the state structure. This is done with the network
* locked because we don't want anything to happen until we are ready.
*/
net_lock();
pkt_recvfrom_initialize(psock, buf, len, from, fromlen, &state);
/* Get the device driver that will service this transfer */
dev = pkt_find_device(conn);
if (dev == NULL)
{
ret = -ENODEV;
goto errout_with_state;
}
/* TODO pkt_recvfrom_initialize() expects from to be of type sockaddr_in, but
* in our case is sockaddr_ll
*/
#if 0
ret = pkt_connect(conn, NULL);
if (ret < 0)
{
goto errout_with_state;
}
#endif
/* Set up the callback in the connection */
state.pr_cb = pkt_callback_alloc(dev, conn);
if (state.pr_cb)
{
state.pr_cb->flags = (PKT_NEWDATA | PKT_POLL);
state.pr_cb->priv = (FAR void *)&state;
state.pr_cb->event = pkt_recvfrom_eventhandler;
/* Wait for either the receive to complete or for an error/timeout to
* occur. NOTES: (1) net_lockedwait will also terminate if a signal
* is received, (2) the network is locked! It will be un-locked while
* the task sleeps and automatically re-locked when the task restarts.
*/
ret = net_lockedwait(&state.pr_sem);
/* Make sure that no further events are processed */
pkt_callback_free(dev, conn, state.pr_cb);
ret = pkt_recvfrom_result(ret, &state);
}
else
{
ret = -EBUSY;
}
errout_with_state:
net_unlock();
pkt_recvfrom_uninitialize(&state);
return ret;
}
#endif /* CONFIG_NET */