/**************************************************************************** * net/local/local.h * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. The * ASF licenses this file to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance with the * License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations * under the License. * ****************************************************************************/ #ifndef __NET_LOCAL_LOCAL_H #define __NET_LOCAL_LOCAL_H /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include #include #include #include #ifdef CONFIG_NET_LOCAL /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ #define LOCAL_NPOLLWAITERS 2 #define LOCAL_NCONTROLFDS 4 /* Packet format in FIFO: * * 1. Sync bytes (7 at most) * 2. End/Start byte * 3. 16-bit packet length (in host order) * 4. Packet data (in host order) */ #define LOCAL_SYNC_BYTE 0x42 /* Byte in sync sequence */ #define LOCAL_END_BYTE 0xbd /* End of sync sequence */ /**************************************************************************** * Public Type Definitions ****************************************************************************/ /* Local, Unix domain socket types */ enum local_type_e { LOCAL_TYPE_UNTYPED = 0, /* Type is not determined until the socket is bound */ LOCAL_TYPE_UNNAMED, /* A Unix socket that is not bound to any name */ LOCAL_TYPE_PATHNAME, /* lc_path holds a null terminated string */ LOCAL_TYPE_ABSTRACT /* lc_path is length zero */ }; /* The state of a Unix socket */ enum local_state_s { /* Common states */ LOCAL_STATE_UNBOUND = 0, /* Created by socket, but not bound */ LOCAL_STATE_BOUND, /* Bound to an path */ /* SOCK_STREAM server only */ LOCAL_STATE_LISTENING, /* Server listening for connections */ /* SOCK_STREAM peers only */ LOCAL_STATE_ACCEPT, /* Client waiting for a connection */ LOCAL_STATE_CONNECTING, /* Non-blocking connect */ LOCAL_STATE_CONNECTED, /* Peer connected */ LOCAL_STATE_DISCONNECTED /* Peer disconnected */ }; /* Representation of a local connection. There are four types of * connection structures: * * 1. Server. A SOCK_STREAM that only listens for and accepts * connections from server. * 2. Client. A SOCK_STREAM peer that connects via the server. * 3. Peer. A connected SOCK_STREAM that sends() and recvs() packets. * May either be the client that connect with the server of the * new peer connect generated with the connection was accepted by * the server. * * And * * 4. Connectionless. Like a peer but using a connectionless datagram * style of communication. SOCK_DRAM support has not yet been * implemented. */ struct devif_callback_s; /* Forward reference */ struct local_conn_s { /* Common prologue of all connection structures. */ /* lc_node supports a doubly linked list: Listening SOCK_STREAM servers * will be linked into a list of listeners; SOCK_STREAM clients will be * linked to the lc_conn lists. */ dq_entry_t lc_node; /* Supports a doubly linked list */ /* This is a list of Local connection callbacks. Each callback represents * a thread that is stalled, waiting for a device-specific event. * REVISIT: Here for commonality with other connection structures; not * used in the current implementation. */ FAR struct devif_callback_s *lc_list; /* Local-socket specific content follows */ /* Fields common to SOCK_STREAM and SOCK_DGRAM */ uint8_t lc_crefs; /* Reference counts on this instance */ uint8_t lc_proto; /* SOCK_STREAM or SOCK_DGRAM */ uint8_t lc_type; /* See enum local_type_e */ uint8_t lc_state; /* See enum local_state_e */ struct file lc_infile; /* File for read-only FIFO (peers) */ struct file lc_outfile; /* File descriptor of write-only FIFO (peers) */ char lc_path[UNIX_PATH_MAX]; /* Path assigned by bind() */ int32_t lc_instance_id; /* Connection instance ID for stream * server<->client connection pair */ #ifdef CONFIG_NET_LOCAL_SCM FAR struct local_conn_s * lc_peer; /* Peer connection instance */ uint16_t lc_cfpcount; /* Control file pointer counter */ FAR struct file * lc_cfps[LOCAL_NCONTROLFDS]; /* Socket message control filep */ #endif /* CONFIG_NET_LOCAL_SCM */ #ifdef CONFIG_NET_LOCAL_STREAM /* SOCK_STREAM fields common to both client and server */ sem_t lc_waitsem; /* Use to wait for a connection to be accepted */ FAR struct socket *lc_psock; /* A reference to the socket structure */ /* The following is a list if poll structures of threads waiting for * socket events. */ struct pollfd *lc_event_fds[LOCAL_NPOLLWAITERS]; struct pollfd lc_inout_fds[2*LOCAL_NPOLLWAITERS]; /* Union of fields unique to SOCK_STREAM client, server, and connected * peers. */ union { /* Fields unique to the SOCK_STREAM server side */ struct { uint8_t lc_pending; /* Number of pending connections */ uint8_t lc_backlog; /* Maximum number of pending connections */ dq_queue_t lc_waiters; /* List of connections waiting to be accepted */ } server; /* Fields unique to the connecting client side */ struct { volatile int lc_result; /* Result of the connection operation (client) */ dq_entry_t lc_waiter; /* Linked to the lc_waiters lists */ } client; } u; #endif /* CONFIG_NET_LOCAL_STREAM */ }; /**************************************************************************** * Public Data ****************************************************************************/ #ifdef __cplusplus # define EXTERN extern "C" extern "C" { #else # define EXTERN extern #endif /* The local socket interface */ EXTERN const struct sock_intf_s g_local_sockif; /**************************************************************************** * Public Function Prototypes ****************************************************************************/ struct sockaddr; /* Forward reference */ struct socket; /* Forward reference */ /**************************************************************************** * Name: local_initialize * * Description: * Initialize the local, Unix domain connection structures. Called once * and only from the common network initialization logic. * ****************************************************************************/ void local_initialize(void); /**************************************************************************** * Name: local_alloc * * Description: * Allocate a new, uninitialized local connection structure. This is * normally something done by the implementation of the socket() API * ****************************************************************************/ FAR struct local_conn_s *local_alloc(void); /**************************************************************************** * Name: local_free * * Description: * Free a local connection structure that is no longer in use. This should * be done by the implementation of close(). * ****************************************************************************/ void local_free(FAR struct local_conn_s *conn); /**************************************************************************** * Name: local_nextconn * * Description: * Traverse the list of allocated Local connections * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ FAR struct local_conn_s *local_nextconn(FAR struct local_conn_s *conn); /**************************************************************************** * Name: local_peerconn * * Description: * Traverse the connections list to find the peer * * Assumptions: * This function must be called with the network locked. * ****************************************************************************/ FAR struct local_conn_s *local_peerconn(FAR struct local_conn_s *conn); /**************************************************************************** * Name: psock_local_bind * * Description: * This function implements the low-level parts of the standard local * bind()operation. * ****************************************************************************/ int psock_local_bind(FAR struct socket *psock, FAR const struct sockaddr *addr, socklen_t addrlen); /**************************************************************************** * Name: psock_local_connect * * Description: * This function sets up a new local connection. The function will * automatically allocate an unused local port for the new * connection. However, another port can be chosen by using the * psock_local_bind() call, after the psock_local_connect() function has * been called. * * This function is called as part of the implementation of sendto * and recvfrom. * * Input Parameters: * psock - A reference to the client-side socket structure * addr - The address of the remote host. * ****************************************************************************/ int psock_local_connect(FAR struct socket *psock, FAR const struct sockaddr *addr); /**************************************************************************** * Name: local_release * * Description: * If the local, Unix domain socket is in the connected state, then * disconnect it. Release the local connection structure in any event * * Input Parameters: * conn - A reference to local connection structure * ****************************************************************************/ int local_release(FAR struct local_conn_s *conn); /**************************************************************************** * Name: local_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(). For the case of local * Unix sockets, psock_listen() calls this function. 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: * On success, zero is returned. On error, a negated errno value is * returned. See listen() for the set of appropriate error values. * ****************************************************************************/ #ifdef CONFIG_NET_LOCAL_STREAM int local_listen(FAR struct socket *psock, int backlog); #endif /**************************************************************************** * Name: local_accept * * Description: * This function implements accept() for Unix domain sockets. See the * description of accept() for further information. * * Input Parameters: * psock The listening Unix domain socket structure * addr Receives the address of the connecting client * addrlen Input: allocated size of 'addr' * Return: returned size of 'addr' * newconn The new, accepted Unix domain connection structure * * Returned Value: * Returns zero (OK) on success or a negated errno value on failure. * See the description of accept of the possible errno values in the * description of accept(). * * Assumptions: * Network is NOT locked. * ****************************************************************************/ #ifdef CONFIG_NET_LOCAL_STREAM int local_accept(FAR struct socket *psock, FAR struct sockaddr *addr, FAR socklen_t *addrlen, FAR struct socket *newsock); #endif /**************************************************************************** * Name: local_sendmsg * * Description: * Implements the sendmsg() operation for the case of the local Unix socket * * Input Parameters: * psock A pointer to a NuttX-specific, internal socket structure * msg msg to send * flags Send flags * * Returned Value: * On success, returns the number of characters sent. On error, a negated * errno value is returned (see sendmsg() for the list of appropriate error * values. * ****************************************************************************/ ssize_t local_sendmsg(FAR struct socket *psock, FAR struct msghdr *msg, int flags); /**************************************************************************** * Name: local_send_packet * * Description: * Send a packet on the write-only FIFO. * * Input Parameters: * filep File structure of write-only FIFO. * buf Data to send * len Length of data to send * preamble Flag to indicate the preamble sync header assembly * * Returned Value: * Zero is returned on success; a negated errno value is returned on any * failure. * ****************************************************************************/ int local_send_packet(FAR struct file *filep, FAR const struct iovec *buf, size_t len, bool preamble); /**************************************************************************** * Name: local_recvmsg * * Description: * recvmsg() 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 * msg Buffer to receive the message * flags Receive flags (ignored for now) * * 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, * recvmsg() will return 0. Otherwise, on errors, a negated errno value is * returned (see recvmsg() for the list of appropriate error values). * ****************************************************************************/ ssize_t local_recvmsg(FAR struct socket *psock, FAR struct msghdr *msg, int flags); /**************************************************************************** * Name: local_fifo_read * * Description: * Read a data from the read-only FIFO. * * Input Parameters: * filep - File structure of write-only FIFO. * buf - Local to store the received data * len - Length of data to receive [in] * Length of data actually received [out] * once - Flag to indicate the buf may only be read once * * Returned Value: * Zero is returned on success; a negated errno value is returned on any * failure. If -ECONNRESET is received, then the sending side has closed * the FIFO. In this case, the returned data may still be valid (if the * returned len > 0). * ****************************************************************************/ int local_fifo_read(FAR struct file *filep, FAR uint8_t *buf, size_t *len, bool once); /**************************************************************************** * Name: local_getaddr * * Description: * Return the Unix domain address of a connection. * * Input Parameters: * conn - The connection * addr - The location to return the address * addrlen - The size of the memory allocate by the caller to receive the * address. * * Returned Value: * Zero (OK) on success; a negated errno value on failure. * ****************************************************************************/ int local_getaddr(FAR struct local_conn_s *conn, FAR struct sockaddr *addr, FAR socklen_t *addrlen); /**************************************************************************** * Name: local_sync * * Description: * Read a sync bytes until the start of the packet is found. * * Input Parameters: * filep - File structure of write-only FIFO. * * Returned Value: * The non-zero size of the following packet is returned on success; a * negated errno value is returned on any failure. * ****************************************************************************/ int local_sync(FAR struct file *filep); /**************************************************************************** * Name: local_create_fifos * * Description: * Create the FIFO pair needed for a SOCK_STREAM connection. * ****************************************************************************/ #ifdef CONFIG_NET_LOCAL_STREAM int local_create_fifos(FAR struct local_conn_s *conn); #endif /**************************************************************************** * Name: local_create_halfduplex * * Description: * Create the half-duplex FIFO needed for SOCK_DGRAM communication. * ****************************************************************************/ #ifdef CONFIG_NET_LOCAL_DGRAM int local_create_halfduplex(FAR struct local_conn_s *conn, FAR const char *path); #endif /**************************************************************************** * Name: local_release_fifos * * Description: * Release references to the FIFO pair used for a SOCK_STREAM connection. * ****************************************************************************/ #ifdef CONFIG_NET_LOCAL_STREAM int local_release_fifos(FAR struct local_conn_s *conn); #endif /**************************************************************************** * Name: local_release_halfduplex * * Description: * Release a reference to the FIFO used for SOCK_DGRAM communication * ****************************************************************************/ #ifdef CONFIG_NET_LOCAL_DGRAM int local_release_halfduplex(FAR struct local_conn_s *conn); #endif /**************************************************************************** * Name: local_open_client_rx * * Description: * Only the client-side Rx FIFO. * ****************************************************************************/ #ifdef CONFIG_NET_LOCAL_STREAM int local_open_client_rx(FAR struct local_conn_s *client, bool nonblock); #endif /**************************************************************************** * Name: local_open_client_tx * * Description: * Only the client-side Tx FIFO. * ****************************************************************************/ #ifdef CONFIG_NET_LOCAL_STREAM int local_open_client_tx(FAR struct local_conn_s *client, bool nonblock); #endif /**************************************************************************** * Name: local_open_server_rx * * Description: * Only the server-side Rx FIFO. * ****************************************************************************/ #ifdef CONFIG_NET_LOCAL_STREAM int local_open_server_rx(FAR struct local_conn_s *server, bool nonblock); #endif /**************************************************************************** * Name: local_open_server_tx * * Description: * Only the server-side Tx FIFO. * ****************************************************************************/ #ifdef CONFIG_NET_LOCAL_STREAM int local_open_server_tx(FAR struct local_conn_s *server, bool nonblock); #endif /**************************************************************************** * Name: local_open_receiver * * Description: * Only the receiving side of the half duplex FIFO. * ****************************************************************************/ #ifdef CONFIG_NET_LOCAL_DGRAM int local_open_receiver(FAR struct local_conn_s *conn, bool nonblock); #endif /**************************************************************************** * Name: local_open_sender * * Description: * Only the sending side of the half duplex FIFO. * ****************************************************************************/ #ifdef CONFIG_NET_LOCAL_DGRAM int local_open_sender(FAR struct local_conn_s *conn, FAR const char *path, bool nonblock); #endif /**************************************************************************** * Name: local_event_pollnotify ****************************************************************************/ void local_event_pollnotify(FAR struct local_conn_s *conn, pollevent_t eventset); /**************************************************************************** * Name: local_pollsetup * * Description: * Setup to monitor events on one Unix domain socket * * Input Parameters: * psock - The Unix domain socket of interest * fds - The structure describing the events to be monitored, OR NULL if * this is a request to stop monitoring events. * * Returned Value: * 0: Success; Negated errno on failure * ****************************************************************************/ int local_pollsetup(FAR struct socket *psock, FAR struct pollfd *fds); /**************************************************************************** * Name: local_pollteardown * * Description: * Teardown monitoring of events on a Unix domain socket * * Input Parameters: * psock - The Unix domain socket of interest * fds - The structure describing the events to be monitored, OR NULL if * this is a request to stop monitoring events. * * Returned Value: * 0: Success; Negated errno on failure * ****************************************************************************/ int local_pollteardown(FAR struct socket *psock, FAR struct pollfd *fds); /**************************************************************************** * Name: local_generate_instance_id * * Description: * Generate instance ID for stream * ****************************************************************************/ int32_t local_generate_instance_id(void); #undef EXTERN #ifdef __cplusplus } #endif #endif /* CONFIG_NET_LOCAL */ #endif /* __NET_LOCAL_LOCAL_H */