Websocket.h

00001 /**
00002 * @author Samuel Mokrani
00003 *
00004 * @section LICENSE
00005 *
00006 * Copyright (c) 2011 mbed
00007 *
00008 * Permission is hereby granted, free of charge, to any person obtaining a copy
00009 * of this software and associated documentation files (the "Software"), to deal
00010 * in the Software without restriction, including without limitation the rights
00011 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00012 * copies of the Software, and to permit persons to whom the Software is
00013 * furnished to do so, subject to the following conditions:
00014 *
00015 * The above copyright notice and this permission notice shall be included in
00016 * all copies or substantial portions of the Software.
00017 *
00018 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00019 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00020 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00021 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00022 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00023 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
00024 * THE SOFTWARE.
00025 *
00026 * @section DESCRIPTION
00027 *    Simple websocket client
00028 *
00029 */
00030 
00031 #ifndef WEBSOCKET_H
00032 #define WEBSOCKET_H
00033 
00034 #include "mbed.h"
00035 
00036 /** Websocket client Class.
00037  *
00038  * Example (ethernet network):
00039  * @code
00040  * #include "mbed.h"
00041  * #include "EthernetInterface.h"
00042  * #include "Websocket.h"
00043  *
00044  * int main() {
00045  *    EthernetInterface eth;
00046  *    eth.connect();
00047  *    SocketAddress ip; 
00048  *    eth.get_ip_address(&ip);
00049  *    const char *p_ip = ip.get_ip_address();
00050  *    printf("IP address: %s\n", p_ip ? p_ip : "None");
00051  *   
00052  *    Websocket ws("ws://echo.websocket.org/");
00053  *    ws.connect();
00054  *    char recv[20];
00055  *    while (1) {
00056  *        int res = ws.send((char*)"WebSocket Hello World!");
00057  *        printf("Error: %d\n", res);
00058  *        if (ws.read(recv)) {
00059  *            printf("rcv: %s\r\n", recv);
00060  *        }
00061  *
00062  *        thread_sleep_for(100ms);
00063  *    }
00064  * }
00065  * @endcode
00066  */
00067  
00068 class Websocket
00069 {
00070     public:
00071         /**
00072         * Constructor
00073         *
00074         * @param url The Websocket url in the form "ws://ip_domain[:port]/path" (by default: port = 80)
00075         * @param iface The NetworkInterface
00076         * @param ca TLS certificate (root_ca_cert)
00077         */
00078         Websocket(char * url, NetworkInterface * iface, const char* ca = nullptr);
00079 
00080         /**
00081         * Connect to the websocket url
00082         *
00083         *@return true if the connection is established, false otherwise
00084         */
00085         bool connect();
00086 
00087         /**
00088         * Send a string according to the websocket format (see rfc 6455)
00089         *
00090         * @param str string to be sent
00091         *
00092         * @returns the number of bytes sent
00093         */
00094         int send(char * str);
00095 
00096         /**
00097         * Read a websocket message
00098         *
00099         * @param message pointer to the string to be read (null if drop frame)
00100         *
00101         * @return true if a websocket frame has been read
00102         */
00103         bool read(char * message);
00104 
00105         /**
00106         * Close the websocket connection
00107         *
00108         * @return true if the connection has been closed, false otherwise
00109         */
00110         bool close();
00111 
00112         /*
00113         * Accessor: get path from the websocket url
00114         *
00115         * @return path
00116         */
00117         char* getPath();
00118 
00119     private:
00120         void fillFields(char * url);
00121         int parseURL(const char* url, char* scheme, size_t maxSchemeLen, char* host, size_t maxHostLen, uint16_t* port, char* path, size_t maxPathLen); //Parse URL
00122         int sendOpcode(uint8_t opcode, char * msg);
00123         int sendLength(uint32_t len, char * msg);
00124         int sendMask(char * msg);
00125         int readChar(char * pC, bool block = true);
00126         
00127         char scheme[8];
00128         uint16_t port;
00129         char host[32];
00130         char path[64];
00131         bool secured;
00132         
00133         Socket* _socket;
00134 
00135         int read(char * buf, int len, int min_len = -1);
00136         int write(char * buf, int len);
00137 };
00138 
00139 #endif