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px4-firmware/nuttx/net/recvfrom.c

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Resync new repository with old repo r5166 git-svn-id: http://svn.code.sf.net/p/nuttx/code/trunk@5153 42af7a65-404d-4744-a932-0658087f49c3
2012-09-17 15:18:44 -03:00
/****************************************************************************
* net/recvfrom.c
*
* Copyright (C) 2007-2009, 2011-2012 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 <arch/irq.h>
#include <nuttx/clock.h>
#include <nuttx/net/uip/uip-arch.h>
#include "net_internal.h"
#include "uip/uip_internal.h"
/****************************************************************************
* Definitions
****************************************************************************/
#define UDPBUF ((struct uip_udpip_hdr *)&dev->d_buf[UIP_LLH_LEN])
#define TCPBUF ((struct uip_tcpip_hdr *)&dev->d_buf[UIP_LLH_LEN])
/****************************************************************************
* Private Types
****************************************************************************/
#if defined(CONFIG_NET_UDP) || defined(CONFIG_NET_TCP)
struct recvfrom_s
{
FAR struct socket *rf_sock; /* The parent socket structure */
#if defined(CONFIG_NET_SOCKOPTS) && !defined(CONFIG_DISABLE_CLOCK)
uint32_t rf_starttime; /* rcv start time for determining timeout */
#endif
FAR struct uip_callback_s *rf_cb; /* Reference to callback instance */
sem_t rf_sem; /* Semaphore signals recv completion */
size_t rf_buflen; /* Length of receive buffer */
char *rf_buffer; /* Pointer to receive buffer */
#ifdef CONFIG_NET_IPv6
FAR struct sockaddr_in6 *rf_from; /* Address of sender */
#else
FAR struct sockaddr_in *rf_from; /* Address of sender */
#endif
size_t rf_recvlen; /* The received length */
int rf_result; /* OK:success, failure:negated errno */
};
#endif /* CONFIG_NET_UDP || CONFIG_NET_TCP */
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Function: recvfrom_newdata
*
* Description:
* Copy the read data from the packet
*
* Parameters:
* dev The sructure of the network driver that caused the interrupt
* pstate recvfrom state structure
*
* Returned Value:
* The number of bytes taken from the packet.
*
* Assumptions:
* Running at the interrupt level
*
****************************************************************************/
#if defined(CONFIG_NET_UDP) || defined(CONFIG_NET_TCP)
static size_t recvfrom_newdata(FAR struct uip_driver_s *dev,
FAR struct recvfrom_s *pstate)
{
size_t recvlen;
/* 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);
nllvdbg("Received %d bytes (of %d)\n", (int)recvlen, (int)dev->d_len);
/* Update the accumulated size of the data read */
pstate->rf_recvlen += recvlen;
pstate->rf_buffer += recvlen;
pstate->rf_buflen -= recvlen;
return recvlen;
}
#endif /* CONFIG_NET_UDP || CONFIG_NET_TCP */
/****************************************************************************
* Function: recvfrom_newtcpdata
*
* Description:
* Copy the read data from the packet
*
* Parameters:
* dev The sructure of the network driver that caused the interrupt
* pstate recvfrom state structure
*
* Returned Value:
* None.
*
* Assumptions:
* Running at the interrupt level
*
****************************************************************************/
#ifdef CONFIG_NET_TCP
static inline void recvfrom_newtcpdata(FAR struct uip_driver_s *dev,
FAR struct recvfrom_s *pstate)
{
/* Take as much data from the packet as we can */
size_t recvlen = recvfrom_newdata(dev, pstate);
/* If there is more data left in the packet that we could not buffer, than
* add it to the read-ahead buffers.
*/
if (recvlen < dev->d_len)
{
#if CONFIG_NET_NTCP_READAHEAD_BUFFERS > 0
FAR struct uip_conn *conn = (FAR struct uip_conn *)pstate->rf_sock->s_conn;
FAR uint8_t *buffer = (FAR uint8_t *)dev->d_appdata + recvlen;
uint16_t buflen = dev->d_len - recvlen;
uint16_t nsaved;
nsaved = uip_datahandler(conn, buffer, buflen);
/* There are complicated buffering issues that are not addressed fully
* here. For example, what if up_datahandler() cannot buffer the
* remainder of the packet? In that case, the data will be dropped but
* still ACKed. Therefore it would not be resent.
*
* This is probably not an issue here because we only get here if the
* read-ahead buffers are empty and there would have to be something
* serioulsy wrong with the configuration not to be able to buffer a
* partial packet in this context.
*/
#ifdef CONFIG_DEBUG_NET
if (nsaved < buflen)
{
ndbg("ERROR: packet data not saved (%d bytes)\n", buflen - nsaved);
}
#endif
#else
ndbg("ERROR: packet data lost (%d bytes)\n", dev->d_len - recvlen);
#endif
}
/* Indicate no data in the buffer */
dev->d_len = 0;
}
#endif /* CONFIG_NET_TCP */
/****************************************************************************
* Function: recvfrom_newudpdata
*
* Description:
* Copy the read data from the packet
*
* Parameters:
* dev The sructure of the network driver that caused the interrupt
* pstate recvfrom state structure
*
* Returned Value:
* None.
*
* Assumptions:
* Running at the interrupt level
*
****************************************************************************/
#ifdef CONFIG_NET_UDP
static inline void recvfrom_newudpdata(FAR struct uip_driver_s *dev,
FAR struct recvfrom_s *pstate)
{
/* Take as much data from the packet as we can */
(void)recvfrom_newdata(dev, pstate);
/* Indicate no data in the buffer */
dev->d_len = 0;
}
#endif /* CONFIG_NET_TCP */
/****************************************************************************
* Function: recvfrom_readahead
*
* Description:
* Copy the read data from the packet
*
* Parameters:
* dev The sructure of the network driver that caused the interrupt
* pstate recvfrom state structure
*
* Returned Value:
* None
*
* Assumptions:
* Running at the interrupt level
*
****************************************************************************/
#if defined(CONFIG_NET_TCP) && CONFIG_NET_NTCP_READAHEAD_BUFFERS > 0
static inline void recvfrom_readahead(struct recvfrom_s *pstate)
{
FAR struct uip_conn *conn = (FAR struct uip_conn *)pstate->rf_sock->s_conn;
FAR struct uip_readahead_s *readahead;
size_t recvlen;
/* Check there is any TCP data already buffered in a read-ahead
* buffer.
*/
do
{
/* Get the read-ahead buffer at the head of the list (if any) */
readahead = (struct uip_readahead_s *)sq_remfirst(&conn->readahead);
if (readahead)
{
/* We have a new buffer... transfer that buffered data into
* the user buffer.
*
* First, get the length of the data to transfer.
*/
if (readahead->rh_nbytes > pstate->rf_buflen)
{
recvlen = pstate->rf_buflen;
}
else
{
recvlen = readahead->rh_nbytes;
}
if (recvlen > 0)
{
/* Copy the read-ahead data into the user buffer */
memcpy(pstate->rf_buffer, readahead->rh_buffer, recvlen);
nllvdbg("Received %d bytes (of %d)\n", recvlen, readahead->rh_nbytes);
/* Update the accumulated size of the data read */
pstate->rf_recvlen += recvlen;
pstate->rf_buffer += recvlen;
pstate->rf_buflen -= recvlen;
}
/* If the read-ahead buffer is empty, then release it. If not, then
* we will have to move the data down and return the buffer to the
* front of the list.
*/
if (recvlen < readahead->rh_nbytes)
{
readahead->rh_nbytes -= recvlen;
memcpy(readahead->rh_buffer, &readahead->rh_buffer[recvlen],
readahead->rh_nbytes);
sq_addfirst(&readahead->rh_node, &conn->readahead);
}
else
{
uip_tcpreadaheadrelease(readahead);
}
}
}
while (readahead && pstate->rf_buflen > 0);
}
#endif /* CONFIG_NET_UDP || CONFIG_NET_TCP */
/****************************************************************************
* Function: recvfrom_timeout
*
* Description:
* Check for recvfrom timeout.
*
* Parameters:
* pstate recvfrom state structure
*
* Returned Value:
* TRUE:timeout FALSE:no timeout
*
* Assumptions:
* Running at the interrupt level
*
****************************************************************************/
#if defined(CONFIG_NET_UDP) || defined(CONFIG_NET_TCP)
#if defined(CONFIG_NET_SOCKOPTS) && !defined(CONFIG_DISABLE_CLOCK)
static int recvfrom_timeout(struct recvfrom_s *pstate)
{
FAR struct socket *psock = 0;
socktimeo_t timeo = 0;
/* Check for a timeout configured via setsockopts(SO_RCVTIMEO). If none...
* we well let the read hang forever (except for the special case below).
*/
/* Get the socket reference from the private data */
psock = pstate->rf_sock;
if (psock)
{
/* Recover the timeout value (zero if no timeout) */
timeo = psock->s_rcvtimeo;
}
/* Use a fixed, configurable delay under the following circumstances:
*
* 1) This delay function has been enabled with CONFIG_NET_TCP_RECVDELAY > 0
* 2) Some data has already been received from the socket. Since this can
* only be true for a TCP/IP socket, this logic applies only to TCP/IP
* sockets. And either
* 3) There is no configured receive timeout, or
* 4) The configured receive timeout is greater than than the delay
*/
#if CONFIG_NET_TCP_RECVDELAY > 0
if ((timeo == 0 || timeo > CONFIG_NET_TCP_RECVDELAY) &&
pstate->rf_recvlen > 0)
{
/* Use the configured timeout */
timeo = CONFIG_NET_TCP_RECVDELAY;
}
#endif
/* Is there an effective timeout? */
if (timeo)
{
/* Yes.. Check if the timeout has elapsed */
return net_timeo(pstate->rf_starttime, timeo);
}
/* No timeout -- hang forever waiting for data. */
return FALSE;
}
#endif /* CONFIG_NET_SOCKOPTS && !CONFIG_DISABLE_CLOCK */
#endif /* CONFIG_NET_UDP || CONFIG_NET_TCP */
/****************************************************************************
* Function: recvfrom_tcpsender
*
* Description:
* Getting the sender's address from the UDP packet
*
* Parameters:
* dev - The device driver data structure
* pstate - the recvfrom state structure
*
* Returned Value:
* None
*
* Assumptions:
* Running at the interrupt level
*
****************************************************************************/
#ifdef CONFIG_NET_TCP
static inline void recvfrom_tcpsender(struct uip_driver_s *dev, struct recvfrom_s *pstate)
{
#ifdef CONFIG_NET_IPv6
FAR struct sockaddr_in6 *infrom = pstate->rf_from;
#else
FAR struct sockaddr_in *infrom = pstate->rf_from;
#endif
if (infrom)
{
infrom->sin_family = AF_INET;
infrom->sin_port = TCPBUF->srcport;
#ifdef CONFIG_NET_IPv6
uip_ipaddr_copy(infrom->sin6_addr.s6_addr, TCPBUF->srcipaddr);
#else
uip_ipaddr_copy(infrom->sin_addr.s_addr, uip_ip4addr_conv(TCPBUF->srcipaddr));
#endif
}
}
#endif
/****************************************************************************
* Function: recvfrom_tcpinterrupt
*
* Description:
* This function is called from the interrupt level to perform the actual
* TCP receive operation via by the uIP layer.
*
* Parameters:
* dev The structure of the network driver that caused the interrupt
* conn The connection structure associated with the socket
* flags Set of events describing why the callback was invoked
*
* Returned Value:
* None
*
* Assumptions:
* Running at the interrupt level
*
****************************************************************************/
#ifdef CONFIG_NET_TCP
static uint16_t recvfrom_tcpinterrupt(struct uip_driver_s *dev, void *conn,
void *pvpriv, uint16_t flags)
{
struct recvfrom_s *pstate = (struct recvfrom_s *)pvpriv;
nllvdbg("flags: %04x\n", flags);
/* 'priv' might be null in some race conditions (?) */
if (pstate)
{
/* If new data is available, then complete the read action. */
if ((flags & UIP_NEWDATA) != 0)
{
/* Copy the data from the packet (saving any unused bytes from the
* packet in the read-ahead buffer).
*/
recvfrom_newtcpdata(dev, pstate);
/* Save the sender's address in the caller's 'from' location */
recvfrom_tcpsender(dev, pstate);
/* Indicate that the data has been consumed and that an ACK
* should be sent.
*/
flags = (flags & ~UIP_NEWDATA) | UIP_SNDACK;
/* Check for transfer complete. We will consider the transfer
* complete in own of two different ways, depending on the setting
* of CONFIG_NET_TCP_RECVDELAY.
*
* 1) If CONFIG_NET_TCP_RECVDELAY == 0 then we will consider the
* TCP/IP transfer complete as soon as any data has been received.
* This is safe because if any additional data is received, it
* will be retained inthe TCP/IP read-ahead buffer until the
* next receive is performed.
* 2) CONFIG_NET_TCP_RECVDELAY > 0 may be set to wait a little
* bit to determine if more data will be received. You might
* do this if read-ahead buffereing is disabled and we want to
* minimize the loss of back-to-back packets. In this case,
* the transfer is complete when either a) the entire user buffer
* is full or 2) when the receive timeout occurs (below).
*/
#if CONFIG_NET_TCP_RECVDELAY > 0
if (pstate->rf_buflen == 0)
#else
if (pstate->rf_recvlen > 0)
#endif
{
nllvdbg("TCP resume\n");
/* The TCP receive buffer is full. Return now and don't allow
* any further TCP call backs.
*/
pstate->rf_cb->flags = 0;
pstate->rf_cb->priv = NULL;
pstate->rf_cb->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.
*/
#if defined(CONFIG_NET_SOCKOPTS) && !defined(CONFIG_DISABLE_CLOCK)
pstate->rf_starttime = clock_systimer();
#endif
}
/* Check for a loss of connection.
*
* UIP_CLOSE: The remote host has closed the connection
* UIP_ABORT: The remote host has aborted the connection
* UIP_TIMEDOUT: Connection aborted due to too many retransmissions.
*/
else if ((flags & (UIP_CLOSE|UIP_ABORT|UIP_TIMEDOUT)) != 0)
{
nllvdbg("error\n");
/* Stop further callbacks */
pstate->rf_cb->flags = 0;
pstate->rf_cb->priv = NULL;
pstate->rf_cb->event = NULL;
/* If the peer gracefully closed the connection, then return zero
* (end-of-file). Otherwise, report a not-connected error
*/
if ((flags & UIP_CLOSE) != 0)
{
pstate->rf_result = 0;
}
else
{
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.
*/
#if defined(CONFIG_NET_SOCKOPTS) && !defined(CONFIG_DISABLE_CLOCK)
else if (recvfrom_timeout(pstate))
{
/* Yes.. the timeout has elapsed... do not allow any further
* callbacks
*/
nllvdbg("TCP timeout\n");
pstate->rf_cb->flags = 0;
pstate->rf_cb->priv = NULL;
pstate->rf_cb->event = NULL;
/* Report an error only if no data has been received. (If
* CONFIG_NET_TCP_RECVDELAY then rf_recvlen should always be
* zero).
*/
#if CONFIG_NET_TCP_RECVDELAY > 0
if (pstate->rf_recvlen == 0)
#endif
{
/* 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 /* CONFIG_NET_SOCKOPTS && !CONFIG_DISABLE_CLOCK */
}
return flags;
}
#endif /* CONFIG_NET_TCP */
/****************************************************************************
* Function: recvfrom_udpsender
*
* Description:
* Getting the sender's address from the UDP packet
*
* Parameters:
* dev - The device driver data structure
* pstate - the recvfrom state structure
*
* Returned Value:
* None
*
* Assumptions:
* Running at the interrupt level
*
****************************************************************************/
#ifdef CONFIG_NET_UDP
static inline void recvfrom_udpsender(struct uip_driver_s *dev, struct recvfrom_s *pstate)
{
#ifdef CONFIG_NET_IPv6
FAR struct sockaddr_in6 *infrom = pstate->rf_from;
#else
FAR struct sockaddr_in *infrom = pstate->rf_from;
#endif
if (infrom)
{
infrom->sin_family = AF_INET;
infrom->sin_port = UDPBUF->srcport;
#ifdef CONFIG_NET_IPv6
uip_ipaddr_copy(infrom->sin6_addr.s6_addr, UDPBUF->srcipaddr);
#else
uip_ipaddr_copy(infrom->sin_addr.s_addr, uip_ip4addr_conv(UDPBUF->srcipaddr));
#endif
}
}
#endif
/****************************************************************************
* Function: recvfrom_udpinterrupt
*
* Description:
* This function is called from the interrupt level to perform the actual
* UDP receive operation via by the uIP layer.
*
* Parameters:
* dev The sructure of the network driver that caused the interrupt
* conn The connection structure associated with the socket
* flags Set of events describing why the callback was invoked
*
* Returned Value:
* None
*
* Assumptions:
* Running at the interrupt level
*
****************************************************************************/
#ifdef CONFIG_NET_UDP
static uint16_t recvfrom_udpinterrupt(struct uip_driver_s *dev, void *pvconn,
void *pvpriv, uint16_t flags)
{
struct recvfrom_s *pstate = (struct recvfrom_s *)pvpriv;
nllvdbg("flags: %04x\n", flags);
/* 'priv' might be null in some race conditions (?) */
if (pstate)
{
/* If new data is available, then complete the read action. */
if ((flags & UIP_NEWDATA) != 0)
{
/* Copy the data from the packet */
recvfrom_newudpdata(dev, pstate);
/* We are finished. */
nllvdbg("UDP done\n");
/* Don't allow any further UDP call backs. */
pstate->rf_cb->flags = 0;
pstate->rf_cb->priv = NULL;
pstate->rf_cb->event = NULL;
/* Save the sender's address in the caller's 'from' location */
recvfrom_udpsender(dev, pstate);
/* Indicate that the data has been consumed */
flags &= ~UIP_NEWDATA;
/* Wake up the waiting thread, returning the number of bytes
* actually read.
*/
sem_post(&pstate->rf_sem);
}
/* No data has been received -- this is some other event... probably a
* poll -- check for a timeout.
*/
#if defined(CONFIG_NET_SOCKOPTS) && !defined(CONFIG_DISABLE_CLOCK)
else if (recvfrom_timeout(pstate))
{
/* Yes.. the timeout has elapsed... do not allow any further
* callbacks
*/
nllvdbg("UDP timeout\n");
/* Stop further callbacks */
pstate->rf_cb->flags = 0;
pstate->rf_cb->priv = NULL;
pstate->rf_cb->event = NULL;
/* Report a timeout error */
pstate->rf_result = -EAGAIN;
/* Wake up the waiting thread */
sem_post(&pstate->rf_sem);
}
#endif /* CONFIG_NET_SOCKOPTS && !CONFIG_DISABLE_CLOCK */
}
return flags;
}
#endif /* CONFIG_NET_UDP */
/****************************************************************************
* 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:
*
****************************************************************************/
#if defined(CONFIG_NET_UDP) || defined(CONFIG_NET_TCP)
static void recvfrom_init(FAR struct socket *psock, FAR void *buf, size_t len,
#ifdef CONFIG_NET_IPv6
FAR struct sockaddr_in6 *infrom,
#else
FAR struct sockaddr_in *infrom,
#endif
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_buflen = len;
pstate->rf_buffer = buf;
pstate->rf_from = infrom;
/* Set up the start time for the timeout */
pstate->rf_sock = psock;
#if defined(CONFIG_NET_SOCKOPTS) && !defined(CONFIG_DISABLE_CLOCK)
pstate->rf_starttime = clock_systimer();
#endif
}
/* The only uninitialization that has to be performed is destroying the
* semaphore.
*/
#define recvfrom_uninit(s) sem_destroy(&(s)->rf_sem)
#endif /* CONFIG_NET_UDP || CONFIG_NET_TCP */
/****************************************************************************
* Function: recvfrom_result
*
* Description:
* Evaluate the result of the recv operations
*
* Parameters:
* result The result of the uip_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:
*
****************************************************************************/
#if defined(CONFIG_NET_UDP) || defined(CONFIG_NET_TCP)
static ssize_t recvfrom_result(int result, struct recvfrom_s *pstate)
{
int save_errno = errno; /* In case something we do changes it */
/* 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)
{
/* This might return EGAIN on a timeout or ENOTCONN on loss of
* connection (TCP only)
*/
return pstate->rf_result;
}
/* If uip_lockedwait failed, then we were probably reawakened by a signal. In
* this case, uip_lockedwait will have set errno appropriately.
*/
if (result < 0)
{
return -save_errno;
}
return pstate->rf_recvlen;
}
#endif /* CONFIG_NET_UDP || CONFIG_NET_TCP */
/****************************************************************************
* 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 (may be NULL)
*
* 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 struct sockaddr_in6 *infrom )
#else
static ssize_t udp_recvfrom(FAR struct socket *psock, FAR void *buf, size_t len,
FAR struct sockaddr_in *infrom )
#endif
{
struct uip_udp_conn *conn = (struct uip_udp_conn *)psock->s_conn;
struct recvfrom_s state;
uip_lock_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 = uip_lock();
recvfrom_init(psock, buf, len, infrom, &state);
/* Setup the UDP remote connection */
ret = uip_udpconnect(conn, NULL);
if (ret < 0)
{
goto errout_with_state;
}
/* Set up the callback in the connection */
state.rf_cb = uip_udpcallbackalloc(conn);
if (state.rf_cb)
{
/* Set up the callback in the connection */
state.rf_cb->flags = UIP_NEWDATA|UIP_POLL;
state.rf_cb->priv = (void*)&state;
state.rf_cb->event = recvfrom_udpinterrupt;
/* Enable the UDP socket */
uip_udpenable(conn);
/* Wait for either the receive to complete or for an error/timeout to occur.
* NOTES: (1) uip_lockedwait 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 = uip_lockedwait(&state. rf_sem);
/* Make sure that no further interrupts are processed */
uip_udpdisable(conn);
uip_udpcallbackfree(conn, state.rf_cb);
ret = recvfrom_result(ret, &state);
}
else
{
ret = -EBUSY;
}
errout_with_state:
uip_unlock(save);
recvfrom_uninit(&state);
return ret;
}
#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 (may be NULL)
*
* 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_TCP
#ifdef CONFIG_NET_IPv6
static ssize_t tcp_recvfrom(FAR struct socket *psock, FAR void *buf, size_t len,
FAR struct sockaddr_in6 *infrom )
#else
static ssize_t tcp_recvfrom(FAR struct socket *psock, FAR void *buf, size_t len,
FAR struct sockaddr_in *infrom )
#endif
{
struct recvfrom_s state;
uip_lock_t save;
int ret;
/* Initialize the state structure. This is done with interrupts
* disabled because we don't want anything to happen until we
* are ready.
*/
save = uip_lock();
recvfrom_init(psock, buf, len, infrom, &state);
/* Handle any any TCP data already buffered in a read-ahead buffer. NOTE
* that there may be read-ahead data to be retrieved even after the
* socket has been disconnected.
*/
#if CONFIG_NET_NTCP_READAHEAD_BUFFERS > 0
recvfrom_readahead(&state);
/* The default return value is the number of bytes that we just copied into
* the user buffer. We will return this if the socket has become disconnected
* or if the user request was completely satisfied with data from the readahead
* buffers.
*/
ret = state.rf_recvlen;
#else
/* Otherwise, the default return value of zero is used (only for the case
* where len == state.rf_buflen is zero).
*/
ret = 0;
#endif
/* Verify that the SOCK_STREAM has been and still is connected */
if (!_SS_ISCONNECTED(psock->s_flags))
{
/* Was any data transferred from the readahead buffer after we were
* disconnected? If so, then return the number of bytes received. We
* will wait to return end disconnection indications the next time that
* recvfrom() is called.
*
* If no data was received (i.e., ret == 0 -- it will not be negative)
* and the connection was gracefully closed by the remote peer, then return
* success. If rf_recvlen is zero, the caller of recvfrom() will get an
* end-of-file indication.
*/
#if CONFIG_NET_NTCP_READAHEAD_BUFFERS > 0
if (ret <= 0 && !_SS_ISCLOSED(psock->s_flags))
#else
if (!_SS_ISCLOSED(psock->s_flags))
#endif
{
/* Nothing was previously received from the readahead buffers.
* The SOCK_STREAM must be (re-)connected in order to receive any
* additional data.
*/
ret = -ENOTCONN;
}
}
/* In general, this uIP-based implementation will not support non-blocking
* socket operations... except in a few cases: Here for TCP receive with read-ahead
* enabled. If this socket is configured as non-blocking then return EAGAIN
* if no data was obtained from the read-ahead buffers.
*/
else
#if CONFIG_NET_NTCP_READAHEAD_BUFFERS > 0
if (_SS_ISNONBLOCK(psock->s_flags))
{
/* Return the number of bytes read from the read-ahead buffer if
* something was received (already in 'ret'); EGAIN if not.
*/
if (ret <= 0)
{
/* Nothing was received */
ret = -EAGAIN;
}
}
/* It is okay to block if we need to. If there is space to receive anything
* more, then we will wait to receive the data. Otherwise return the number
* of bytes read from the read-ahead buffer (already in 'ret').
*/
else
#endif
/* We get here when we we decide that we need to setup the wait for incoming
* TCP/IP data. Just a few more conditions to check:
*
* 1) Make sure thet there is buffer space to receive additional data
* (state.rf_buflen > 0). This could be zero, for example, if read-ahead
* buffering was enabled and we filled the user buffer with data from
* the read-ahead buffers. Aand
* 2) if read-ahead buffering is enabled (CONFIG_NET_NTCP_READAHEAD_BUFFERS > 0)
* and delay logic is disabled (CONFIG_NET_TCP_RECVDELAY == 0), then we
* not want to wait if we already obtained some data from the read-ahead
* buffer. In that case, return now with what we have (don't want for more
* because there may be no timeout).
*/
#if CONFIG_NET_TCP_RECVDELAY == 0 && CONFIG_NET_NTCP_READAHEAD_BUFFERS > 0
if (state.rf_recvlen == 0 && state.rf_buflen > 0)
#else
if (state.rf_buflen > 0)
#endif
{
struct uip_conn *conn = (struct uip_conn *)psock->s_conn;
/* Set up the callback in the connection */
state.rf_cb = uip_tcpcallbackalloc(conn);
if (state.rf_cb)
{
state.rf_cb->flags = UIP_NEWDATA|UIP_POLL|UIP_CLOSE|UIP_ABORT|UIP_TIMEDOUT;
state.rf_cb->priv = (void*)&state;
state.rf_cb->event = recvfrom_tcpinterrupt;
/* Wait for either the receive to complete or for an error/timeout to occur.
* NOTES: (1) uip_lockedwait will also terminate if a signal is received, (2)
* interrupts may be disabled! They will be re-enabled while the task sleeps
* and automatically re-enabled when the task restarts.
*/
ret = uip_lockedwait(&state.rf_sem);
/* Make sure that no further interrupts are processed */
uip_tcpcallbackfree(conn, state.rf_cb);
ret = recvfrom_result(ret, &state);
}
else
{
ret = -EBUSY;
}
}
uip_unlock(save);
recvfrom_uninit(&state);
return (ssize_t)ret;
}
#endif /* CONFIG_NET_TCP */
/****************************************************************************
* Global Functions
****************************************************************************/
/****************************************************************************
* Function: psock_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:
* 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 sent. If no data is
* available to be received and the peer has performed an orderly shutdown,
* recv() will return 0. Othwerwise, on errors, -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 psock_recvfrom(FAR struct socket *psock, FAR void *buf, size_t len,
int flags,FAR struct sockaddr *from,
FAR socklen_t *fromlen)
{
#if defined(CONFIG_NET_UDP) || defined(CONFIG_NET_TCP)
#ifdef CONFIG_NET_IPv6
FAR struct sockaddr_in6 *infrom = (struct sockaddr_in6 *)from;
#else
FAR struct sockaddr_in *infrom = (struct sockaddr_in *)from;
#endif
#endif
ssize_t ret;
int err;
/* Verify that non-NULL pointers were passed */
#ifdef CONFIG_DEBUG
if (!buf)
{
err = EINVAL;
goto errout;
}
#endif
/* Verify that the sockfd corresponds to valid, allocated socket */
if (!psock || psock->s_crefs <= 0)
{
err = EBADF;
goto errout;
}
/* If a 'from' address has been provided, verify that it is large
* enough to hold this address family.
*/
if (from)
{
#ifdef CONFIG_NET_IPv6
if (*fromlen < sizeof(struct sockaddr_in6))
#else
if (*fromlen < sizeof(struct sockaddr_in))
#endif
{
err = EINVAL;
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 */
#if defined(CONFIG_NET_UDP) && defined(CONFIG_NET_TCP)
if (psock->s_type == SOCK_STREAM)
{
ret = tcp_recvfrom(psock, buf, len, infrom);
}
else
{
ret = udp_recvfrom(psock, buf, len, infrom);
}
#elif defined(CONFIG_NET_TCP)
ret = tcp_recvfrom(psock, buf, len, infrom);
#elif defined(CONFIG_NET_UDP)
ret = udp_recvfrom(psock, buf, len, infrom);
#else
ret = -ENOSYS;
#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:
errno = err;
return ERROR;
}
/****************************************************************************
* 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 (may be NULL)
* 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;
/* Get the underlying socket structure */
psock = sockfd_socket(sockfd);
/* Then let psock_recvfrom() do all of the work */
return psock_recvfrom(psock, buf, len, flags, from, fromlen);
}
#endif /* CONFIG_NET */