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     virtual nsapi_error_t socket_open(nsapi_socket_t *handle, nsapi_protocol_t proto);
00050 
00051     virtual nsapi_error_t socket_close(nsapi_socket_t handle);
00052 
00053     virtual nsapi_error_t socket_bind(nsapi_socket_t handle, const SocketAddress &address);
00054 
00055     virtual nsapi_error_t socket_listen(nsapi_socket_t handle, int backlog);
00056 
00057     virtual nsapi_error_t socket_connect(nsapi_socket_t handle, const SocketAddress &address);
00058 
00059     virtual nsapi_error_t socket_accept(nsapi_socket_t server,
00060                                         nsapi_socket_t *handle, SocketAddress *address=0);
00061 
00062     virtual nsapi_size_or_error_t socket_send(nsapi_socket_t handle,
00063             const void *data, nsapi_size_t size);
00064 
00065     virtual nsapi_size_or_error_t socket_recv(nsapi_socket_t handle,
00066             void *data, nsapi_size_t size);
00067 
00068     virtual nsapi_size_or_error_t socket_sendto(nsapi_socket_t handle, const SocketAddress &address,
00069             const void *data, nsapi_size_t size);
00070 
00071     virtual nsapi_size_or_error_t socket_recvfrom(nsapi_socket_t handle, SocketAddress *address,
00072             void *buffer, nsapi_size_t size);
00073 
00074     virtual void socket_attach(nsapi_socket_t handle, void (*callback)(void *), void *data);
00075 
00076 protected:
00077 
00078     class CellularSocket
00079     {
00080     public:
00081         // Socket id from cellular device
00082         int id;
00083         // Being connected means remote ip address and port are set
00084         bool connected;
00085         nsapi_protocol_t proto;
00086         SocketAddress remoteAddress;
00087         SocketAddress localAddress;
00088         void (*_cb)(void *);
00089         void *_data;
00090         bool created;
00091         bool rx_avail; // used to synchronize reading from modem
00092     };
00093 
00094     /**
00095     * Gets maximum number of sockets modem supports
00096     */
00097     virtual int get_max_socket_count() = 0;
00098 
00099     /**
00100     * Gets maximum packet size
00101     */
00102     virtual int get_max_packet_size() = 0;
00103 
00104     /**
00105     * Checks if modem supports the given protocol
00106     *
00107     * @param protocol   Protocol type
00108     */
00109     virtual bool is_protocol_supported(nsapi_protocol_t protocol) = 0;
00110 
00111     /**
00112     * Implements modem specific AT command set for socket closing
00113     *
00114     * @param sock_id   Socket id
00115     */
00116     virtual nsapi_error_t socket_close_impl(int sock_id) = 0;
00117 
00118     /**
00119     * Implements modem specific AT command set for creating socket
00120     *
00121     * @param socket   Cellular socket handle
00122     */
00123     virtual nsapi_error_t create_socket_impl(CellularSocket *socket) = 0;
00124 
00125     /**
00126     * Implements modem specific AT command set for sending data
00127     *
00128     * @param socket   Cellular socket handle
00129     * @param address  The SocketAddress of the remote host
00130     * @param data     Buffer of data to send to the host
00131     * @param size     Size of the buffer in bytes
00132     * @return         Number of sent bytes on success, negative error
00133     *                 code on failure
00134     */
00135     virtual nsapi_size_or_error_t socket_sendto_impl(CellularSocket *socket, const SocketAddress &address,
00136             const void *data, nsapi_size_t size) = 0;
00137 
00138     /**
00139      *  Implements modem specific AT command set for receiving data
00140      *
00141      *  @param socket   Socket handle
00142      *  @param address  Destination for the source address or NULL
00143      *  @param buffer   Destination buffer for data received from the host
00144      *  @param size     Size of the buffer in bytes
00145      *  @return         Number of received bytes on success, negative error
00146      *                  code on failure
00147      */
00148     virtual nsapi_size_or_error_t socket_recvfrom_impl(CellularSocket *socket, SocketAddress *address,
00149             void *buffer, nsapi_size_t size) = 0;
00150 
00151     // socket container
00152     CellularSocket **_socket;
00153 
00154     // number of socket slots allocated in socket container
00155     int _socket_count;
00156 
00157     // IP address
00158     char _ip[PDP_IPV6_SIZE];
00159 
00160     // PDP context id
00161     int _cid;
00162 
00163     // stack type from PDP context
00164     nsapi_ip_stack_t _stack_type;
00165 };
00166 
00167 } // namespace mbed
00168 
00169 #endif // AT_CELLULAR_STACK_H_