/****************************************************************************
* net/recvfrom.c
*
* Copyright (C) 2007 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* 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 <string.h>
#include <errno.h>
#include <arch/irq.h>
#include <nuttx/clock.h>
#include <net/uip/uip-arch.h>
#include "net-internal.h"
/****************************************************************************
* Definitions
****************************************************************************/
#define TCP_TIMEO 10 /* Deciseconds after data received before recv() returns */
/****************************************************************************
* Private Types
****************************************************************************/
struct recvfrom_s
{
#if defined(CONFIG_NET_SOCKOPTS) && !defined(CONFIG_DISABLE_CLOCK)
FAR struct socket *rf_sock; /* The parent socket structure */
#endif
sem_t rf_sem; /* Semaphore signals recv completion */
size_t rf_buflen; /* Length of receive buffer */
char *rf_buffer; /* Pointer to receive buffer */
#ifndef CONFIG_DISABLE_CLOCK
uint32 rf_starttime; /* rcv start time for determining timeout */
#endif
size_t rf_recvlen; /* The received length */
int rf_result; /* OK on success, otherwise a negated errno. */
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Function: recvfrom_interrupt
*
* Description:
* This function is called from the interrupt level to perform the actual
* receive operation via by the uIP layer.
*
* Parameters:
* dev The sructure of the network driver that caused the interrupt
* private An instance of struct recvfrom_s cast to void*
*
* Returned Value:
* None
*
* Assumptions:
* Running at the interrupt level
*
****************************************************************************/
static void recvfrom_interrupt(struct uip_driver_s *dev, void *private)
{
struct recvfrom_s *pstate = (struct recvfrom_s *)private;
FAR struct socket *psock;
size_t recvlen;
/* 'private' might be null in some race conditions (?) */
if (pstate)
{
/* Get the socket reference from the private data */
psock = pstate->rf_sock;
/* If new data is available, then complete the read action. */
if (uip_newdata())
{
/* Get the length of the data to return */
if (dev->d_len > pstate->rf_buflen)
{
recvlen = pstate->rf_buflen;
}
else
{
recvlen = dev->d_len;
}
/* Copy the new appdata into the user buffer */
memcpy(pstate->rf_buffer, dev->d_appdata, recvlen);
/* Update the accumulated size of the data read */
pstate->rf_recvlen += recvlen;
pstate->rf_buffer += recvlen;
pstate->rf_buflen -= recvlen;
/* Are we finished? If this is a UDP socket or if the user
* buffer has been filled, then we are finished.
*/
#ifdef CONFIG_NET_UDP
if (psock->s_type == SOCK_DGRAM)
{
struct uip_udp_conn *udp_conn;
/* Don't allow any further UDP call backs. */
udp_conn = (struct uip_udp_conn *)psock->s_conn;
udp_conn->private = NULL;
udp_conn->event = NULL;
/* Wake up the waiting thread, returning the number of bytes
* actually read.
*/
sem_post(&pstate->rf_sem);
}
else
#endif
if (pstate->rf_buflen == 0)
{
struct uip_conn *conn;
/* The TCP receive buffer is full. Return now, perhaps truncating
* the received data (need to fix that).
*
* Don't allow any further TCP call backs.
*/
conn = (struct uip_conn *)psock->s_conn;
conn->data_private = NULL;
conn->data_event = NULL;
/* Wake up the waiting thread, returning the number of bytes
* actually read.
*/
sem_post(&pstate->rf_sem);
}
/* Reset the timeout. We will want a short timeout to terminate
* the TCP receive.
*/
#ifndef CONFIG_DISABLE_CLOCK
pstate->rf_starttime = g_system_timer;
#endif
}
/* Check for a loss of connection */
else if ((uip_flags & (UIP_CLOSE|UIP_ABORT|UIP_TIMEDOUT)) != 0)
{
/* Stop further callbacks */
#ifdef CONFIG_NET_UDP
if (psock->s_type == SOCK_DGRAM)
{
struct uip_udp_conn *udp_conn = (struct uip_udp_conn *)psock->s_conn;
udp_conn->private = NULL;
udp_conn->event = NULL;
}
else
#endif
{
struct uip_conn *conn = (struct uip_conn *)psock->s_conn;
conn->data_private = NULL;
conn->data_event = NULL;
}
/* Report not connected */
pstate->rf_result = -ENOTCONN;
/* Wake up the waiting thread */
sem_post(&pstate->rf_sem);
}
/* No data has been received -- this is some other event... probably a
* poll -- check for a timeout.
*/
#ifndef CONFIG_DISABLE_CLOCK
else
{
socktimeo_t timeo;
/* If this is a TCP socket that has already received some data,
* than we will always use a short timeout.
*/
if (pstate->rf_recvlen > 0)
{
/* Use the short timeout */
timeo = TCP_TIMEO;
}
/* No.. check for a timeout configured via setsockopts(SO_RCVTIMEO).
* If non... we well let the read hang forever.
*/
else
{
#ifdef CONFIG_NET_SOCKOPTS
timeo = psock->s_rcvtimeo;
#else
timeo = 0;
#endif
}
/* Is there an effective timeout? */
if (timeo)
{
/* Yes.. Check if the timeout has elapsed */
if (net_timeo(pstate->rf_starttime, timeo))
{
/* Yes.. the timeout has elapsed... do not allow any further
* callbacks
*/
#ifdef CONFIG_NET_UDP
if (psock->s_type == SOCK_DGRAM)
{
struct uip_udp_conn *udp_conn;
/* Stop further callbacks */
udp_conn = (struct uip_udp_conn *)psock->s_conn;
udp_conn->private = NULL;
udp_conn->event = NULL;
/* Report a timeout error */
pstate->rf_result = -EAGAIN;
}
else
#endif
{
struct uip_conn *conn;
conn = (struct uip_conn *)psock->s_conn;
conn->data_private = NULL;
conn->data_event = NULL;
/* Report an error only if no data has been received */
if (pstate->rf_recvlen == 0)
{
/* Report the timeout error */
pstate->rf_result = -EAGAIN;
}
}
/* Wake up the waiting thread, returning either the error -EAGAIN
* that signals the timeout event or the data received up to
* the point tht the timeout occured (no error).
*/
sem_post(&pstate->rf_sem);
}
}
}
#endif
}
}
/****************************************************************************
* Function: recvfrom_init
*
* Description:
* Initialize the state structure
*
* 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 recvfrom_init(FAR struct socket *psock, FAR void *buf, size_t len,
struct recvfrom_s *pstate)
{
/* Initialize the state structure. */
memset(pstate, 0, sizeof(struct recvfrom_s));
(void)sem_init(&pstate->rf_sem, 0, 0); /* Doesn't really fail */
pstate->rf_sock = psock;
pstate->rf_buflen = len;
pstate->rf_buffer = buf;
#ifndef CONFIG_DISABLE_CLOCK
/* Set up the start time for the timeout */
pstate->rf_starttime = g_system_timer;
#endif
}
/****************************************************************************
* Function: recvfrom_result
*
* Description:
* Evaluate the result of the recv operations
*
* Parameters:
* result The result of the sem_wait 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 recvfrom_result(int result, struct recvfrom_s *pstate)
{
int save_errno = *get_errno_ptr(); /* In case something we do changes it */
/* Release semaphore in the state structure */
sem_destroy(&pstate->rf_sem);
/* Check for a error/timeout detected by the interrupt handler. Errors are
* signaled by negative errno values for the rcv length
*/
if (pstate->rf_result < 0)
{
/* Return EGAIN on a timeout or ENOTCONN on loss of connection */
return pstate->rf_result;
}
/* If sem_wait failed, then we were probably reawakened by a signal. In
* this case, sem_wait will have set errno appropriately.
*/
if (result < 0)
{
return -save_errno;
}
return pstate->rf_recvlen;
}
/****************************************************************************
* Function: udp_recvfrom
*
* Description:
* Perform the recvfrom operation for a UDP SOCK_DGRAM
*
* Parameters:
* psock Pointer to the socket structure for the SOCK_DRAM socket
* buf Buffer to receive data
* len Length of buffer
* infrom INET ddress of source
*
* Returned Value:
* On success, returns the number of characters sent. On error,
* -errno is returned (see recvfrom for list of errnos).
*
* Assumptions:
*
****************************************************************************/
#ifdef CONFIG_NET_UDP
#ifdef CONFIG_NET_IPv6
static ssize_t udp_recvfrom(FAR struct socket *psock, FAR void *buf, size_t len,
FAR const struct sockaddr_in6 *infrom )
#else
static ssize_t udp_recvfrom(FAR struct socket *psock, FAR void *buf, size_t len,
FAR const struct sockaddr_in *infrom )
#endif
{
struct uip_udp_conn *udp_conn;
struct recvfrom_s state;
irqstate_t save;
int ret;
/* Perform the UDP recvfrom() operation */
/* Initialize the state structure. This is done with interrupts
* disabled because we don't want anything to happen until we
* are ready.
*/
save = irqsave();
recvfrom_init(psock, buf, len, &state);
/* Setup the UDP socket */
ret = uip_udpconnect(psock->s_conn, NULL);
if (ret < 0)
{
irqrestore(save);
return ret;
}
/* Set up the callback in the connection */
udp_conn = (struct uip_udp_conn *)psock->s_conn;
udp_conn->private = (void*)&state;
udp_conn->event = recvfrom_interrupt;
/* Enable the UDP socket */
uip_udpenable(psock->s_conn);
/* Wait for either the receive to complete or for an error/timeout to occur.
* NOTES: (1) sem_wait will also terminate if a signal is received, (2)
* interrupts are disabled! They will be re-enabled while the task sleeps
* and automatically re-enabled when the task restarts.
*/
ret = sem_wait(&state. rf_sem);
/* Make sure that no further interrupts are processed */
uip_udpdisable(psock->s_conn);
udp_conn->private = NULL;
udp_conn->event = NULL;
irqrestore(save);
#warning "Needs to return server address"
return recvfrom_result(ret, &state);
}
#endif /* CONFIG_NET_UDP */
/****************************************************************************
* Function: tcp_recvfrom
*
* Description:
* Perform the recvfrom operation for a TCP/IP SOCK_STREAM
*
* Parameters:
* psock Pointer to the socket structure for the SOCK_DRAM socket
* buf Buffer to receive data
* len Length of buffer
* infrom INET ddress of source
*
* Returned Value:
* On success, returns the number of characters sent. On error,
* -errno is returned (see recvfrom for list of errnos).
*
* Assumptions:
*
****************************************************************************/
#ifdef CONFIG_NET_IPv6
static ssize_t tcp_recvfrom(FAR struct socket *psock, FAR void *buf, size_t len,
FAR const struct sockaddr_in6 *infrom )
#else
static ssize_t tcp_recvfrom(FAR struct socket *psock, FAR void *buf, size_t len,
FAR const struct sockaddr_in *infrom )
#endif
{
struct uip_conn *conn;
struct recvfrom_s state;
irqstate_t save;
int ret;
/* Verify that the SOCK_STREAM has been connected */
if (_SS_ISCONNECTED(psock->s_flags))
{
/* The SOCK_STREAM must be connect in order to recive */
return -ENOTCONN;
}
/* Initialize the state structure. This is done with interrupts
* disabled because we don't want anything to happen until we
* are ready.
*/
save = irqsave();
recvfrom_init(psock, buf, len, &state);
/* Set up the callback in the connection */
conn = (struct uip_conn *)psock->s_conn;
conn->data_private = (void*)&state;
conn->data_event = recvfrom_interrupt;
/* Wait for either the receive to complete or for an error/timeout to occur.
* NOTES: (1) sem_wait will also terminate if a signal is received, (2)
* interrupts are disabled! They will be re-enabled while the task sleeps
* and automatically re-enabled when the task restarts.
*/
ret = sem_wait(&state. rf_sem);
/* Make sure that no further interrupts are processed */
conn->data_private = NULL;
conn->data_event = NULL;
irqrestore(save);
#warning "Needs to return server address"
return recvfrom_result(ret, &state);
}
/****************************************************************************
* Global Functions
****************************************************************************/
/****************************************************************************
* Function: recvfrom
*
* Description:
* 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
* initialized to the size of the buffer associated with from, and modified
* on return to indicate the actual size of the address stored there.
*
* Parameters:
* sockfd Socket descriptor of socket
* buf Buffer to receive data
* len Length of buffer
* flags Receive flags
* from Address of source
* fromlen The length of the address structure
*
* Returned Value:
* On success, returns the number of characters sent. On error,
* -1 is returned, and errno is set appropriately:
*
* EAGAIN
* The socket is marked non-blocking and the receive operation would block,
* or a receive timeout had been set and the timeout expired before data
* was received.
* EBADF
* The argument sockfd is an invalid descriptor.
* ECONNREFUSED
* A remote host refused to allow the network connection (typically because
* it is not running the requested service).
* EFAULT
* The receive buffer pointer(s) point outside the process's address space.
* EINTR
* The receive was interrupted by delivery of a signal before any data were
* available.
* EINVAL
* Invalid argument passed.
* ENOMEM
* Could not allocate memory.
* ENOTCONN
* The socket is associated with a connection-oriented protocol and has
* not been connected.
* ENOTSOCK
* The argument sockfd does not refer to a socket.
*
* Assumptions:
*
****************************************************************************/
ssize_t recvfrom(int sockfd, FAR void *buf, size_t len, int flags, FAR struct sockaddr *from,
FAR socklen_t *fromlen)
{
FAR struct socket *psock;
#ifdef CONFIG_NET_IPv6
FAR const struct sockaddr_in6 *infrom = (const struct sockaddr_in6 *)from;
#else
FAR const struct sockaddr_in *infrom = (const struct sockaddr_in *)from;
#endif
ssize_t ret;
int err;
/* Verify that non-NULL pointers were passed */
if (!buf || !from || !fromlen)
{
err = EINVAL;
goto errout;
}
/* Get the underlying socket structure */
/* Verify that the sockfd corresponds to valid, allocated socket */
psock = sockfd_socket(sockfd);
if (!psock || psock->s_crefs <= 0)
{
err = EBADF;
goto errout;
}
/* Verify that a valid address has been provided */
#ifdef CONFIG_NET_IPv6
if (from->sa_family != AF_INET6 || *fromlen < sizeof(struct sockaddr_in6))
#else
if (from->sa_family != AF_INET || *fromlen < sizeof(struct sockaddr_in))
#endif
{
err = EBADF;
goto errout;
}
/* Set the socket state to receiving */
psock->s_flags = _SS_SETSTATE(psock->s_flags, _SF_RECV);
/* Perform the TCP/IP or UDP recv() operation */
#ifdef CONFIG_NET_UDP
if (psock->s_type == SOCK_STREAM)
#endif
{
ret = tcp_recvfrom(psock, buf, len, infrom);
}
#ifdef CONFIG_NET_UDP
else
{
ret = udp_recvfrom(psock, buf, len, infrom);
}
#endif
/* Set the socket state to idle */
psock->s_flags = _SS_SETSTATE(psock->s_flags, _SF_IDLE);
/* Handle returned errors */
if (ret < 0)
{
err = -ret;
goto errout;
}
/* Success return */
return ret;
errout:
*get_errno_ptr() = err;
return ERROR;
}
#endif /* CONFIG_NET */