/**************************************************************************** * net/local/local_recvfrom.c * * Copyright (C) 2015 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * 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 #if defined(CONFIG_NET) && defined(CONFIG_NET_LOCAL) #include #include #include #include #include #include #include #include "socket/socket.h" #include "local/local.h" /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ #ifndef MIN # define MIN(a,b) ((a) < (b) ? (a) : (b)) #endif /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: psock_fifo_read * * Description: * A thin layer around local_fifo_read that handles socket-related loss-of- * connection events. * ****************************************************************************/ static int psock_fifo_read(FAR struct socket *psock, FAR void *buf, FAR size_t *readlen) { FAR struct local_conn_s *conn = (FAR struct local_conn_s *)psock->s_conn; int ret; ret = local_fifo_read(&conn->lc_infile, buf, readlen); if (ret < 0) { /* -ECONNRESET is a special case. We may or not have received * data, then the peer closed the connection. */ if (ret == -ECONNRESET) { nerr("ERROR: Lost connection: %d\n", ret); /* Report an ungraceful loss of connection. This should * eventually be reported as ENOTCONN. */ psock->s_flags &= ~(_SF_CONNECTED | _SF_CLOSED); conn->lc_state = LOCAL_STATE_DISCONNECTED; /* Did we receive any data? */ if (*readlen <= 0) { /* No.. return the ECONNRESET error now. Otherwise, * process the received data and return ENOTCONN the * next time that psock_recvfrom() is called. */ return ret; } } else { nerr("ERROR: Failed to read packet: %d\n", ret); return ret; } } return OK; } /**************************************************************************** * Name: psock_stream_recvfrom * * Description: * psock_stream_recvfrom() receives messages from a local stream socket. * * 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, -1 is returned, and errno * is set appropriately (see receive from for the complete list). * ****************************************************************************/ #ifdef CONFIG_NET_LOCAL_STREAM static inline ssize_t psock_stream_recvfrom(FAR struct socket *psock, FAR void *buf, size_t len, int flags, FAR struct sockaddr *from, FAR socklen_t *fromlen) { FAR struct local_conn_s *conn = (FAR struct local_conn_s *)psock->s_conn; size_t readlen; int ret; /* Verify that this is a connected peer socket */ if (conn->lc_state != LOCAL_STATE_CONNECTED) { nerr("ERROR: not connected\n"); return -ENOTCONN; } /* The incoming FIFO should be open */ DEBUGASSERT(conn->lc_infile.f_inode != NULL); /* Are there still bytes in the FIFO from the last packet? */ if (conn->u.peer.lc_remaining == 0) { /* No.. Sync to the start of the next packet in the stream and get * the size of the next packet. */ ret = local_sync(&conn->lc_infile); if (ret < 0) { nerr("ERROR: Failed to get packet length: %d\n", ret); return ret; } else if (ret > UINT16_MAX) { nerr("ERROR: Packet is too big: %d\n", ret); return -E2BIG; } conn->u.peer.lc_remaining = (uint16_t)ret; } /* Read the packet */ readlen = MIN(conn->u.peer.lc_remaining, len); ret = psock_fifo_read(psock, buf, &readlen); if (ret < 0) { return ret; } /* Adjust the number of bytes remaining to be read from the packet */ DEBUGASSERT(readlen <= conn->u.peer.lc_remaining); conn->u.peer.lc_remaining -= readlen; /* Return the address family */ if (from) { ret = local_getaddr(conn, from, fromlen); if (ret < 0) { return ret; } } return readlen; } #endif /* CONFIG_NET_LOCAL_STREAM */ /**************************************************************************** * Name: psock_dgram_recvfrom * * Description: * psock_dgram_recvfrom() receives messages from a local datagram socket. * * 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. Otherwise, on * errors, -1 is returned, and errno is set appropriately (see receive * from for the complete list). * ****************************************************************************/ #ifdef CONFIG_NET_LOCAL_DGRAM static inline ssize_t psock_dgram_recvfrom(FAR struct socket *psock, FAR void *buf, size_t len, int flags, FAR struct sockaddr *from, FAR socklen_t *fromlen) { FAR struct local_conn_s *conn = (FAR struct local_conn_s *)psock->s_conn; uint16_t pktlen; size_t readlen; int ret; /* We keep packet sizes in a uint16_t, so there is a upper limit to the * 'len' that can be supported. */ DEBUGASSERT(len <= UINT16_MAX); /* Verify that this is a bound, un-connected peer socket */ if (conn->lc_state != LOCAL_STATE_BOUND) { /* Either not bound to address or it is connected */ nerr("ERROR: Connected or not bound\n"); return -EISCONN; } /* The incoming FIFO should not be open */ DEBUGASSERT(conn->lc_infile.f_inode == NULL); /* Make sure that half duplex FIFO has been created */ ret = local_create_halfduplex(conn, conn->lc_path); if (ret < 0) { nerr("ERROR: Failed to create FIFO for %s: %d\n", conn->lc_path, ret); return ret; } /* Open the receiving side of the transfer */ ret = local_open_receiver(conn, _SS_ISNONBLOCK(psock->s_flags) || (flags & MSG_DONTWAIT) != 0); if (ret < 0) { nerr("ERROR: Failed to open FIFO for %s: %d\n", conn->lc_path, ret); goto errout_with_halfduplex; return ret; } /* Sync to the start of the next packet in the stream and get the size of * the next packet. */ ret = local_sync(&conn->lc_infile); if (ret < 0) { nerr("ERROR: Failed to get packet length: %d\n", ret); goto errout_with_infd; } else if (ret > UINT16_MAX) { nerr("ERROR: Packet is too big: %d\n", ret); goto errout_with_infd; } pktlen = ret; /* Read the packet */ readlen = MIN(pktlen, len); ret = psock_fifo_read(psock, buf, &readlen); if (ret < 0) { goto errout_with_infd; } /* If there are unread bytes remaining in the packet, flush the remainder * of the packet to the bit bucket. */ DEBUGASSERT(readlen <= pktlen); if (readlen < pktlen) { uint8_t bitbucket[32]; uint16_t remaining; size_t tmplen; remaining = pktlen - readlen; do { /* Read 32 bytes into the bit bucket */ readlen = MIN(remaining, 32); ret = psock_fifo_read(psock, bitbucket, &tmplen); if (ret < 0) { goto errout_with_infd; } /* Adjust the number of bytes remaining to be read from the packet */ DEBUGASSERT(tmplen <= remaining); remaining -= tmplen; } while (remaining > 0); } /* Now we can close the read-only file descriptor */ file_close(&conn->lc_infile); conn->lc_infile.f_inode = NULL; /* Release our reference to the half duplex FIFO */ local_release_halfduplex(conn); /* Return the address family */ if (from) { ret = local_getaddr(conn, from, fromlen); if (ret < 0) { return ret; } } return readlen; errout_with_infd: /* Close the read-only file descriptor */ file_close(&conn->lc_infile); conn->lc_infile.f_inode = NULL; errout_with_halfduplex: /* Release our reference to the half duplex FIFO */ local_release_halfduplex(conn); return ret; } #endif /* CONFIG_NET_LOCAL_STREAM */ /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: local_recvfrom * * Description: * local_recvfrom() receives messages from a local 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. * * 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 recv_from() for the complete list of appropriate error * values). * ****************************************************************************/ ssize_t local_recvfrom(FAR struct socket *psock, FAR void *buf, size_t len, int flags, FAR struct sockaddr *from, FAR socklen_t *fromlen) { DEBUGASSERT(psock && psock->s_conn && buf); /* Check for a stream socket */ #ifdef CONFIG_NET_LOCAL_STREAM if (psock->s_type == SOCK_STREAM) { return psock_stream_recvfrom(psock, buf, len, flags, from, fromlen); } else #endif #ifdef CONFIG_NET_LOCAL_DGRAM if (psock->s_type == SOCK_DGRAM) { return psock_dgram_recvfrom(psock, buf, len, flags, from, fromlen); } else #endif { DEBUGPANIC(); nerr("ERROR: Unrecognized socket type: %s\n", psock->s_type); return -EINVAL; } } #endif /* CONFIG_NET && CONFIG_NET_LOCAL */