ESP8266Interface.h

00001 /* ESP8266 implementation of NetworkInterfaceAPI
00002  * Copyright (c) 2015 ARM Limited
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License");
00005  * you may not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 
00017 #ifndef ESP8266_INTERFACE_H
00018 #define ESP8266_INTERFACE_H
00019 
00020 #include "mbed.h"
00021 #include "ESP8266.h"
00022 
00023 
00024 #define ESP8266_SOCKET_COUNT 5
00025 
00026 /** ESP8266Interface class
00027  *  Implementation of the NetworkStack for the ESP8266
00028  */
00029 class ESP8266Interface : public NetworkStack, public WiFiInterface
00030 {
00031 public:
00032     /** ESP8266Interface lifetime
00033      * @param tx        TX pin
00034      * @param rx        RX pin
00035      * @param debug     Enable debugging
00036      */
00037     ESP8266Interface(PinName tx, PinName rx, bool debug = false);
00038 
00039     /** Start the interface
00040      *
00041      *  Attempts to connect to a WiFi network. Requires ssid and passphrase to be set.
00042      *  If passphrase is invalid, NSAPI_ERROR_AUTH_ERROR is returned.
00043      *
00044      *  @return         0 on success, negative error code on failure
00045      */
00046     virtual int connect();
00047 
00048     /** Start the interface
00049      *
00050      *  Attempts to connect to a WiFi network.
00051      *
00052      *  @param ssid      Name of the network to connect to
00053      *  @param pass      Security passphrase to connect to the network
00054      *  @param security  Type of encryption for connection (Default: NSAPI_SECURITY_NONE)
00055      *  @param channel   This parameter is not supported, setting it to anything else than 0 will result in NSAPI_ERROR_UNSUPPORTED
00056      *  @return          0 on success, or error code on failure
00057      */
00058     virtual int connect(const char *ssid, const char *pass, nsapi_security_t security = NSAPI_SECURITY_NONE,
00059                                   uint8_t channel = 0);
00060 
00061     /** Set the WiFi network credentials
00062      *
00063      *  @param ssid      Name of the network to connect to
00064      *  @param pass      Security passphrase to connect to the network
00065      *  @param security  Type of encryption for connection
00066      *                   (defaults to NSAPI_SECURITY_NONE)
00067      *  @return          0 on success, or error code on failure
00068      */
00069     virtual int set_credentials(const char *ssid, const char *pass, nsapi_security_t security = NSAPI_SECURITY_NONE);
00070 
00071     /** Set the WiFi network channel - NOT SUPPORTED
00072      *
00073      * This function is not supported and will return NSAPI_ERROR_UNSUPPORTED
00074      *
00075      *  @param channel   Channel on which the connection is to be made, or 0 for any (Default: 0)
00076      *  @return          Not supported, returns NSAPI_ERROR_UNSUPPORTED
00077      */
00078     virtual int set_channel(uint8_t channel);
00079 
00080     /** Stop the interface
00081      *  @return             0 on success, negative on failure
00082      */
00083     virtual int disconnect();
00084 
00085     /** Get the internally stored IP address
00086      *  @return             IP address of the interface or null if not yet connected
00087      */
00088     virtual const char *get_ip_address();
00089 
00090     /** Get the internally stored MAC address
00091      *  @return             MAC address of the interface
00092      */
00093     virtual const char *get_mac_address();
00094 
00095      /** Get the local gateway
00096      *
00097      *  @return         Null-terminated representation of the local gateway
00098      *                  or null if no network mask has been recieved
00099      */
00100     virtual const char *get_gateway();
00101 
00102     /** Get the local network mask
00103      *
00104      *  @return         Null-terminated representation of the local network mask
00105      *                  or null if no network mask has been recieved
00106      */
00107     virtual const char *get_netmask();
00108 
00109     /** Gets the current radio signal strength for active connection
00110      *
00111      * @return          Connection strength in dBm (negative value)
00112      */
00113     virtual int8_t get_rssi();
00114 
00115     /** Scan for available networks
00116      *
00117      * This function will block.
00118      *
00119      * @param  ap       Pointer to allocated array to store discovered AP
00120      * @param  count    Size of allocated @a res array, or 0 to only count available AP
00121      * @param  timeout  Timeout in milliseconds; 0 for no timeout (Default: 0)
00122      * @return          Number of entries in @a, or if @a count was 0 number of available networks, negative on error
00123      *                  see @a nsapi_error
00124      */
00125     virtual int scan(WiFiAccessPoint *res, unsigned count);
00126 
00127 protected:
00128     /** Open a socket
00129      *  @param handle       Handle in which to store new socket
00130      *  @param proto        Type of socket to open, NSAPI_TCP or NSAPI_UDP
00131      *  @return             0 on success, negative on failure
00132      */
00133     virtual int socket_open(void **handle, nsapi_protocol_t proto);
00134 
00135     /** Close the socket
00136      *  @param handle       Socket handle
00137      *  @return             0 on success, negative on failure
00138      *  @note On failure, any memory associated with the socket must still
00139      *        be cleaned up
00140      */
00141     virtual int socket_close(void *handle);
00142 
00143     /** Bind a server socket to a specific port
00144      *  @param handle       Socket handle
00145      *  @param address      Local address to listen for incoming connections on
00146      *  @return             0 on success, negative on failure.
00147      */
00148     virtual int socket_bind(void *handle, const SocketAddress &address);
00149 
00150     /** Start listening for incoming connections
00151      *  @param handle       Socket handle
00152      *  @param backlog      Number of pending connections that can be queued up at any
00153      *                      one time [Default: 1]
00154      *  @return             0 on success, negative on failure
00155      */
00156     virtual int socket_listen(void *handle, int backlog);
00157 
00158     /** Connects this TCP socket to the server
00159      *  @param handle       Socket handle
00160      *  @param address      SocketAddress to connect to
00161      *  @return             0 on success, negative on failure
00162      */
00163     virtual int socket_connect(void *handle, const SocketAddress &address);
00164 
00165     /** Accept a new connection.
00166      *  @param handle       Handle in which to store new socket
00167      *  @param server       Socket handle to server to accept from
00168      *  @return             0 on success, negative on failure
00169      *  @note This call is not-blocking, if this call would block, must
00170      *        immediately return NSAPI_ERROR_WOULD_WAIT
00171      */
00172     virtual int socket_accept(void *handle, void **socket, SocketAddress *address);
00173 
00174     /** Send data to the remote host
00175      *  @param handle       Socket handle
00176      *  @param data         The buffer to send to the host
00177      *  @param size         The length of the buffer to send
00178      *  @return             Number of written bytes on success, negative on failure
00179      *  @note This call is not-blocking, if this call would block, must
00180      *        immediately return NSAPI_ERROR_WOULD_WAIT
00181      */
00182     virtual int socket_send(void *handle, const void *data, unsigned size);
00183 
00184     /** Receive data from the remote host
00185      *  @param handle       Socket handle
00186      *  @param data         The buffer in which to store the data received from the host
00187      *  @param size         The maximum length of the buffer
00188      *  @return             Number of received bytes on success, negative on failure
00189      *  @note This call is not-blocking, if this call would block, must
00190      *        immediately return NSAPI_ERROR_WOULD_WAIT
00191      */
00192     virtual int socket_recv(void *handle, void *data, unsigned size);
00193 
00194     /** Send a packet to a remote endpoint
00195      *  @param handle       Socket handle
00196      *  @param address      The remote SocketAddress
00197      *  @param data         The packet to be sent
00198      *  @param size         The length of the packet to be sent
00199      *  @return             The number of written bytes on success, negative on failure
00200      *  @note This call is not-blocking, if this call would block, must
00201      *        immediately return NSAPI_ERROR_WOULD_WAIT
00202      */
00203     virtual int socket_sendto(void *handle, const SocketAddress &address, const void *data, unsigned size);
00204 
00205     /** Receive a packet from a remote endpoint
00206      *  @param handle       Socket handle
00207      *  @param address      Destination for the remote SocketAddress or null
00208      *  @param buffer       The buffer for storing the incoming packet data
00209      *                      If a packet is too long to fit in the supplied buffer,
00210      *                      excess bytes are discarded
00211      *  @param size         The length of the buffer
00212      *  @return             The number of received bytes on success, negative on failure
00213      *  @note This call is not-blocking, if this call would block, must
00214      *        immediately return NSAPI_ERROR_WOULD_WAIT
00215      */
00216     virtual int socket_recvfrom(void *handle, SocketAddress *address, void *buffer, unsigned size);
00217 
00218     /** Register a callback on state change of the socket
00219      *  @param handle       Socket handle
00220      *  @param callback     Function to call on state change
00221      *  @param data         Argument to pass to callback
00222      *  @note Callback may be called in an interrupt context.
00223      */
00224     virtual void socket_attach(void *handle, void (*callback)(void *), void *data);
00225 
00226     /** Provide access to the NetworkStack object
00227      *
00228      *  @return The underlying NetworkStack object
00229      */
00230     virtual NetworkStack *get_stack()
00231     {
00232         return this;
00233     }
00234 
00235 private:
00236     ESP8266 _esp;
00237     bool _ids[ESP8266_SOCKET_COUNT];
00238 
00239     char ap_ssid[33]; /* 32 is what 802.11 defines as longest possible name; +1 for the \0 */
00240     nsapi_security_t ap_sec;
00241     uint8_t ap_ch;
00242     char ap_pass[64]; /* The longest allowed passphrase */
00243 
00244     void event();
00245 
00246     struct {
00247         void (*callback)(void *);
00248         void *data;
00249     } _cbs[ESP8266_SOCKET_COUNT];
00250 };
00251 
00252 #endif