/**************************************************************************** * net/socket/listen.c * * Copyright (C) 2007-2009, 201-2017 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 #include #include #include #include #include "socket/socket.h" #if defined(CONFIG_NET) && CONFIG_NSOCKET_DESCRIPTORS > 0 /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: psock_listen * * Description: * To accept connections, a socket is first created with psock_socket(), a * willingness to accept incoming connections and a queue limit for * incoming connections are specified with psock_listen(), and then the * connections are accepted with psock_accept(). The psock_listen() call * applies only to sockets of type SOCK_STREAM or SOCK_SEQPACKET. * * Input Parameters: * psock Reference to an internal, boound socket structure. * backlog The maximum length the queue of pending connections may grow. * If a connection request arrives with the queue full, the client * may receive an error with an indication of ECONNREFUSED or, * if the underlying protocol supports retransmission, the request * may be ignored so that retries succeed. * * Returned Value: * Returns zero (OK) on success. On failure, it returns a negated errno * value to indicate the nature of the error. * * EADDRINUSE * Another socket is already listening on the same port. * EOPNOTSUPP * The socket is not of a type that supports the listen operation. * ****************************************************************************/ int psock_listen(FAR struct socket *psock, int backlog) { int ret; DEBUGASSERT(psock != NULL); /* Verify that the sockfd corresponds to a connected SOCK_STREAM */ if (psock == NULL || psock->s_conn == NULL) { nerr("ERROR: Invalid or unconnected socket\n"); return -EINVAL; } /* Let the address family's listen() method handle the operation */ DEBUGASSERT(psock->s_sockif != NULL && psock->s_sockif->si_listen != NULL); ret = psock->s_sockif->si_listen(psock, backlog); if (ret < 0) { nerr("ERROR: si_listen failed: %d\n", ret); return ret; } psock->s_flags |= _SF_LISTENING; return OK; } /**************************************************************************** * Name: listen * * Description: * To accept connections, a socket is first created with socket(), a * willingness to accept incoming connections and a queue limit for incoming * connections are specified with listen(), and then the connections are * accepted with accept(). The listen() call applies only to sockets of * type SOCK_STREAM or SOCK_SEQPACKET. * * Input Parameters: * sockfd Socket descriptor of the bound socket * backlog The maximum length the queue of pending connections may grow. * If a connection request arrives with the queue full, the client * may receive an error with an indication of ECONNREFUSED or, * if the underlying protocol supports retransmission, the request * may be ignored so that retries succeed. * * Returned Value: * On success, zero is returned. On error, -1 is returned, and errno is set * appropriately. * * EADDRINUSE * Another socket is already listening on the same port. * EBADF * The argument 'sockfd' is not a valid descriptor. * ENOTSOCK * The argument 'sockfd' is not a socket. * EOPNOTSUPP * The socket is not of a type that supports the listen operation. * ****************************************************************************/ int listen(int sockfd, int backlog) { FAR struct socket *psock = sockfd_socket(sockfd); int errcode; int ret; /* Verify that the sockfd corresponds to valid, allocated socket */ if (psock == NULL || psock->s_crefs <= 0) { /* It is not a valid socket description. Distinguish between the * cases where sockfd is a just invalid and when it is a valid file * descriptor used in the wrong context. */ #if CONFIG_NFILE_DESCRIPTORS > 0 if ((unsigned int)sockfd < CONFIG_NFILE_DESCRIPTORS) { errcode = ENOTSOCK; } else #endif { errcode = EBADF; } set_errno(errcode); return ERROR; } /* The let psock_listen to the work. If psock_listen() fails, it will have * set the errno variable. */ ret = psock_listen(psock, backlog); if (ret < 0) { set_errno(-ret); return ERROR; } return OK; } #endif /* CONFIG_NET && CONFIG_NSOCKET_DESCRIPTORS */