Diff: features/netsocket/Socket.h

Revision:

0:5b88d5760320

Child:

1:9db0e321a9f4

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/features/netsocket/Socket.h	Tue Dec 17 23:23:45 2019 +0000
@@ -0,0 +1,287 @@
+/*
+ * Copyright (c) 2015 ARM Limited
+ *
+ * Licensed 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.
+ */
+
+/** @file Socket.h Abstract Socket interface */
+/** @addtogroup netsocket
+ * Mbed OS Socket API
+ * @{ */
+
+#ifndef SOCKET_H
+#define SOCKET_H
+
+#include "netsocket/SocketAddress.h"
+#include "Callback.h"
+
+/** Socket interface.
+ *
+ * This class defines the Mbed OS Socket API.
+ * Socket is an abstract interface for communicating with remote endpoints.
+ *
+ * This API is intended for applications and libraries instead of
+ * protocol-specific implementations. For example, TCPSocket
+ * and UDPSocket are implementations of the Socket interface.
+ * Socket API is intentionally not protocol-specific, and allows all protocol
+ * to provide the same API regardless of the underlying transport mechanism.
+ */
+class Socket {
+public:
+    /** Destroy a socket.
+     *
+     *  Closes socket if the socket is still open.
+     */
+    virtual ~Socket() {}
+
+    /** Closes the socket.
+     *
+     *  Closes any open connection and deallocates any memory associated
+     *  with the socket. Called from destructor if socket is not closed.
+     *
+     *  @return         NSAPI_ERROR_OK on success, negative error code on failure
+     */
+    virtual nsapi_error_t close() = 0;
+
+    /** Connects socket to a remote address.
+     *
+     *  Attempts to make connection on connection-mode protocol or set or reset
+     *  the peer address on connectionless protocol.
+     *
+     *  Connectionless protocols also use the connected address to filter
+     *  incoming packets for recv() and recvfrom() calls.
+     *
+     *  To reset the peer address, there must be zero initialized(default constructor) SocketAddress
+     *  objects in the address parameter.
+     *
+     *  @note If connect() fails it is recommended to close the Socket and create
+     *  a new one before attempting to reconnect.
+     *
+     *  @param address  The SocketAddress of the remote peer.
+     *  @return         NSAPI_ERROR_OK on success, negative error code on failure.
+     */
+    virtual nsapi_error_t connect(const SocketAddress &address) = 0;
+
+    /** Send data on a socket
+     *
+     *  The socket must be connected to a remote host before send() call.
+     *  Returns the number of bytes sent from the buffer.
+     *  In case of connectionless socket, sends data to pre-specified remote.
+     *
+     *  By default, send blocks until all data is sent. If socket is set to
+     *  non-blocking or times out, a partial amount can be written.
+     *  NSAPI_ERROR_WOULD_BLOCK is returned if no data was written.
+     *
+     *  @param data     Buffer of data to send to the host.
+     *  @param size     Size of the buffer in bytes.
+     *  @return         Number of sent bytes on success, negative error
+     *                  code on failure.
+     */
+    virtual nsapi_size_or_error_t send(const void *data, nsapi_size_t size) = 0;
+
+    /** Receive data from a socket.
+     *
+     *  Receive data from connected socket, or in the case of connectionless socket,
+     *  equivalent to calling recvfrom(NULL, data, size).
+     *
+     *  If socket is connected, only packets coming from connected peer address
+     *  are accepted.
+     *
+     *  @note recv() is allowed write to data buffer even if an error occurs.
+     *
+     *  By default, recv blocks until some data is received. If socket is set to
+     *  non-blocking or times out, NSAPI_ERROR_WOULD_BLOCK can be returned to
+     *  indicate no data.
+     *
+     *  @param data     Destination buffer for data received from the host.
+     *  @param size     Size of the buffer in bytes.
+     *  @return         Number of received bytes on success, negative error
+     *                  code on failure. If no data is available to be received
+     *                  and the peer has performed an orderly shutdown,
+     *                  recv() returns 0.
+     */
+    virtual nsapi_size_or_error_t recv(void *data, nsapi_size_t size) = 0;
+
+    /** Send a message on a socket.
+     *
+     * The sendto() function sends a message through a connection-mode or connectionless-mode socket.
+     * If the socket is a connectionless-mode socket, the message is sent to the address specified.
+     * If the socket is a connected-mode socket, address is ignored.
+     *
+     * By default, sendto blocks until data is sent. If socket is set to
+     * non-blocking or times out, NSAPI_ERROR_WOULD_BLOCK is returned
+     * immediately.
+     *
+     *  @param address  Remote address
+     *  @param data     Buffer of data to send to the host
+     *  @param size     Size of the buffer in bytes
+     *  @return         Number of sent bytes on success, negative error
+     *                  code on failure
+     */
+    virtual nsapi_size_or_error_t sendto(const SocketAddress &address,
+                                         const void *data, nsapi_size_t size) = 0;
+
+    /** Receive a data from a socket
+     *
+     *  Receives a data and stores the source address in address if address
+     *  is not NULL. Returns the number of bytes written into the buffer.
+     *
+     *  If socket is connected, only packets coming from connected peer address
+     *  are accepted.
+     *
+     *  @note recvfrom() is allowed write to address and data buffers even if error occurs.
+     *
+     *  By default, recvfrom blocks until a datagram is received. If socket is set to
+     *  non-blocking or times out with no data, NSAPI_ERROR_WOULD_BLOCK
+     *  is returned.
+     *
+     *  @param address  Destination for the source address or NULL
+     *  @param data     Destination buffer for datagram received from the host
+     *  @param size     Size of the buffer in bytes
+     *  @return         Number of received bytes on success, negative error
+     *                  code on failure
+     */
+    virtual nsapi_size_or_error_t recvfrom(SocketAddress *address,
+                                           void *data, nsapi_size_t size) = 0;
+
+    /** Bind a specific address to a socket.
+     *
+     *  Binding a socket specifies the address and port on which to receive
+     *  data. If the IP address is zeroed, only the port is bound.
+     *
+     *  @param address  Local address to bind.
+     *  @return         NSAPI_ERROR_OK on success, negative error code on failure.
+     */
+    virtual nsapi_error_t bind(const SocketAddress &address) = 0;
+
+    /** Set blocking or non-blocking mode of the socket.
+     *
+     *  Initially all sockets are in blocking mode. In non-blocking mode
+     *  blocking operations such as send/recv/accept return
+     *  NSAPI_ERROR_WOULD_BLOCK if they cannot continue.
+     *
+     *  set_blocking(false) is equivalent to set_timeout(0)
+     *  set_blocking(true) is equivalent to set_timeout(-1)
+     *
+     *  @param blocking true for blocking mode, false for non-blocking mode.
+     */
+    virtual void set_blocking(bool blocking) = 0;
+
+    /** Set timeout on blocking socket operations.
+     *
+     *  Initially all sockets have unbounded timeouts. NSAPI_ERROR_WOULD_BLOCK
+     *  is returned if a blocking operation takes longer than the specified
+     *  timeout. A timeout of 0 removes the timeout from the socket. A negative
+     *  value gives the socket an unbounded timeout.
+     *
+     *  set_timeout(0) is equivalent to set_blocking(false)
+     *  set_timeout(-1) is equivalent to set_blocking(true)
+     *
+     *  @param timeout  Timeout in milliseconds
+     */
+    virtual void set_timeout(int timeout) = 0;
+
+    /** Register a callback on state change of the socket.
+     *
+     *  The specified callback is called on state changes, such as when
+     *  the socket can receive/send/accept successfully and when an error
+     *  occurs. The callback may also be called spuriously without reason.
+     *
+     *  The callback may be called in an interrupt context and should not
+     *  perform expensive operations such as receive/send calls.
+     *
+     *  Note! This is not intended as a replacement for a poll or attach-like
+     *  asynchronous API, but rather as a building block for constructing
+     *  such functionality. The exact timing of the registered function
+     *  is not guaranteed and susceptible to change.
+     *
+     *  @param func     Function to call on state change.
+     */
+    virtual void sigio(mbed::Callback<void()> func) = 0;
+
+    /** Set socket options.
+     *
+     *  setsockopt() allows an application to pass stack-specific options
+     *  to the underlying stack using stack-specific level and option names,
+     *  or to request generic options using levels from nsapi_socket_level_t.
+     *
+     *  For unsupported options, NSAPI_ERROR_UNSUPPORTED is returned
+     *  and the socket is unmodified.
+     *
+     *  @param level    Stack-specific protocol level or nsapi_socket_level_t.
+     *  @param optname  Level-specific option name.
+     *  @param optval   Option value.
+     *  @param optlen   Length of the option value.
+     *  @return         NSAPI_ERROR_OK on success, negative error code on failure.
+     */
+    virtual nsapi_error_t setsockopt(int level, int optname, const void *optval, unsigned optlen) = 0;
+
+    /** Get socket options.
+     *
+     *  getsockopt() allows an application to retrieve stack-specific options
+     *  from the underlying stack using stack-specific level and option names,
+     *  or to request generic options using levels from nsapi_socket_level_t.
+     *
+     *  For unsupported options, NSAPI_ERROR_UNSUPPORTED is returned
+     *  and the socket is unmodified.
+     *
+     *  @param level    Stack-specific protocol level or nsapi_socket_level_t.
+     *  @param optname  Level-specific option name.
+     *  @param optval   Destination for option value.
+     *  @param optlen   Length of the option value.
+     *  @return         NSAPI_ERROR_OK on success, negative error code on failure.
+     */
+    virtual nsapi_error_t getsockopt(int level, int optname, void *optval, unsigned *optlen) = 0;
+
+    /** Accepts a connection on a socket.
+     *
+     *  The server socket must be bound and set to listen for connections.
+     *  On a new connection, returns connected network socket to call close()
+     *  that deallocates the resources. Referencing a returned pointer after a close()
+     *  call is not allowed and leads to undefined behavior.
+     *
+     *  By default, accept blocks until incoming connection occurs. If socket is set to
+     *  non-blocking or times out, error is set to NSAPI_ERROR_WOULD_BLOCK.
+     *
+     *  @param error      Pointer to storage of the error value or NULL.
+     *  @return           Pointer to a socket.
+     */
+    virtual Socket *accept(nsapi_error_t *error = NULL) = 0;
+
+    /** Listen for incoming connections.
+     *
+     *  Marks the socket as a passive socket that can be used to accept
+     *  incoming connections.
+     *
+     *  @param backlog  Number of pending connections that can be queued
+     *                  simultaneously, defaults to 1.
+     *  @return         NSAPI_ERROR_OK on success, negative error code on failure.
+     */
+    virtual nsapi_error_t listen(int backlog = 1) = 0;
+
+    /** Get the remote-end peer associated with this socket.
+     *
+     * Copy the remote peer address to a SocketAddress structure pointed by
+     * address parameter. Socket must be connected to have a peer address
+     * associated.
+     *
+     *  @param address  Pointer to SocketAddress structure.
+     *  @return         NSAPI_ERROR_OK on success, negative error code on failure.
+     */
+    virtual nsapi_error_t getpeername(SocketAddress *address) = 0;
+};
+
+
+#endif
+
+/** @}*/