AT_CellularStack.h

00001 /*
00002  * Copyright (c) 2017, Arm Limited and affiliates.
00003  * SPDX-License-Identifier: Apache-2.0
00004  *
00005  * Licensed under the Apache License, Version 2.0 (the "License");
00006  * you may not use this file except in compliance with the License.
00007  * You may obtain a copy of the License at
00008  *
00009  *     http://www.apache.org/licenses/LICENSE-2.0
00010  *
00011  * Unless required by applicable law or agreed to in writing, software
00012  * distributed under the License is distributed on an "AS IS" BASIS,
00013  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00014  * See the License for the specific language governing permissions and
00015  * limitations under the License.
00016  */
00017 
00018 #ifndef AT_CELLULAR_STACK_H_
00019 #define AT_CELLULAR_STACK_H_
00020 
00021 #include "AT_CellularBase.h"
00022 #include "NetworkStack.h"
00023 
00024 namespace mbed {
00025 
00026 // <PDP_addr_1> and <PDP_addr_2>: each is a string type that identifies the MT in the address space applicable to the PDP.
00027 // The string is given as dot-separated numeric (0-255) parameter of the form:
00028 // a1.a2.a3.a4 for IPv4 and
00029 // a1.a2.a3.a4.a5.a6.a7.a8.a9.a10.a11.a12.a13.a14.a15.a16 for IPv6.
00030 #define PDP_IPV6_SIZE 63+1
00031 
00032 /**
00033  * Class AT_CellularStack.
00034  *
00035  * Implements NetworkStack and introduces interface for modem specific stack implementations.
00036  */
00037 class AT_CellularStack : public NetworkStack, public AT_CellularBase
00038 {
00039 
00040 public:
00041     AT_CellularStack(ATHandler &at, int cid, nsapi_ip_stack_t stack_type);
00042     virtual ~AT_CellularStack();
00043 
00044 public: // NetworkStack
00045 
00046     virtual const char *get_ip_address();
00047 protected: // NetworkStack
00048 
00049     /**
00050      * Modem specific socket stack initialization
00051      *
00052      *  @return 0 on success
00053      */
00054     virtual nsapi_error_t socket_stack_init();
00055 
00056     virtual nsapi_error_t socket_open(nsapi_socket_t *handle, nsapi_protocol_t proto);
00057 
00058     virtual nsapi_error_t socket_close(nsapi_socket_t handle);
00059 
00060     virtual nsapi_error_t socket_bind(nsapi_socket_t handle, const SocketAddress &address);
00061 
00062     virtual nsapi_error_t socket_listen(nsapi_socket_t handle, int backlog);
00063 
00064     virtual nsapi_error_t socket_connect(nsapi_socket_t handle, const SocketAddress &address);
00065 
00066     virtual nsapi_error_t socket_accept(nsapi_socket_t server,
00067                                         nsapi_socket_t *handle, SocketAddress *address=0);
00068 
00069     virtual nsapi_size_or_error_t socket_send(nsapi_socket_t handle,
00070             const void *data, nsapi_size_t size);
00071 
00072     virtual nsapi_size_or_error_t socket_recv(nsapi_socket_t handle,
00073             void *data, nsapi_size_t size);
00074 
00075     virtual nsapi_size_or_error_t socket_sendto(nsapi_socket_t handle, const SocketAddress &address,
00076             const void *data, nsapi_size_t size);
00077 
00078     virtual nsapi_size_or_error_t socket_recvfrom(nsapi_socket_t handle, SocketAddress *address,
00079             void *buffer, nsapi_size_t size);
00080 
00081     virtual void socket_attach(nsapi_socket_t handle, void (*callback)(void *), void *data);
00082 
00083 protected:
00084 
00085     class CellularSocket
00086     {
00087     public:
00088         // Socket id from cellular device
00089         int id;
00090         // Being connected means remote ip address and port are set
00091         bool connected;
00092         nsapi_protocol_t proto;
00093         SocketAddress remoteAddress;
00094         SocketAddress localAddress;
00095         void (*_cb)(void *);
00096         void *_data;
00097         bool created; // socket has been created on modem stack
00098         bool started; // socket has been opened on modem stack
00099         bool tx_ready; // socket is ready for sending on modem stack
00100         bool rx_avail; // socket has data for reading on modem stack
00101     };
00102 
00103     /**
00104     * Gets maximum number of sockets modem supports
00105     */
00106     virtual int get_max_socket_count() = 0;
00107 
00108     /**
00109     * Gets maximum packet size
00110     */
00111     virtual int get_max_packet_size() = 0;
00112 
00113     /**
00114     * Checks if modem supports the given protocol
00115     *
00116     * @param protocol   Protocol type
00117     */
00118     virtual bool is_protocol_supported(nsapi_protocol_t protocol) = 0;
00119 
00120     /**
00121     * Implements modem specific AT command set for socket closing
00122     *
00123     * @param sock_id   Socket id
00124     */
00125     virtual nsapi_error_t socket_close_impl(int sock_id) = 0;
00126 
00127     /**
00128     * Implements modem specific AT command set for creating socket
00129     *
00130     * @param socket   Cellular socket handle
00131     */
00132     virtual nsapi_error_t create_socket_impl(CellularSocket *socket) = 0;
00133 
00134     /**
00135     * Implements modem specific AT command set for sending data
00136     *
00137     * @param socket   Cellular socket handle
00138     * @param address  The SocketAddress of the remote host
00139     * @param data     Buffer of data to send to the host
00140     * @param size     Size of the buffer in bytes
00141     * @return         Number of sent bytes on success, negative error
00142     *                 code on failure
00143     */
00144     virtual nsapi_size_or_error_t socket_sendto_impl(CellularSocket *socket, const SocketAddress &address,
00145             const void *data, nsapi_size_t size) = 0;
00146 
00147     /**
00148      *  Implements modem specific AT command set for receiving data
00149      *
00150      *  @param socket   Socket handle
00151      *  @param address  Destination for the source address or NULL
00152      *  @param buffer   Destination buffer for data received from the host
00153      *  @param size     Size of the buffer in bytes
00154      *  @return         Number of received bytes on success, negative error
00155      *                  code on failure
00156      */
00157     virtual nsapi_size_or_error_t socket_recvfrom_impl(CellularSocket *socket, SocketAddress *address,
00158             void *buffer, nsapi_size_t size) = 0;
00159 
00160     // socket container
00161     CellularSocket **_socket;
00162 
00163     // number of socket slots allocated in socket container
00164     int _socket_count;
00165 
00166     // IP address
00167     char _ip[PDP_IPV6_SIZE];
00168 
00169     // PDP context id
00170     int _cid;
00171 
00172     // stack type from PDP context
00173     nsapi_ip_stack_t _stack_type;
00174 };
00175 
00176 } // namespace mbed
00177 
00178 #endif // AT_CELLULAR_STACK_H_