Example program with HTTPServer and sensor data streaming over TCPSockets, using Donatien Garnier's Net APIs and services code on top of LWIP. Files StreamServer.h and .cpp encapsulate streaming over TCPSockets. Broadcast is done by sendToAll(), and all incoming data is echoed back to the client. Echo code can be replaced with some remote control of the streaming interface. See main() that shows how to periodically send some data to all subscribed clients. To subscribe, a client should open a socket at <mbed_ip> port 123. I used few lines in TCL code to set up a quick sink for the data. HTTP files are served on port 80 concurrently to the streaming.

Dependencies:   mbed

Revision:
0:e614f7875b60
Child:
1:3ee499525aa5
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/services/mysql/MySQLClient.cpp	Sat Jun 12 06:01:50 2010 +0000
@@ -0,0 +1,527 @@
+
+/*
+Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)
+ 
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+ 
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include "MySQLClient.h"
+#include "sha1.h" //For 4.1+ passwords
+#include "mycrypt.h" //For 4.0- passwords
+
+#define __DEBUG
+#include "dbg/dbg.h"
+
+#define MYSQL_TIMEOUT_MS 15000
+#define MYSQL_PORT 3306
+
+#define BUF_SIZE 256
+
+#define CLIENT_LONG_PASSWORD     1
+#define CLIENT_CONNECT_WITH_DB   8
+#define CLIENT_PROTOCOL_41       512
+#define CLIENT_INTERACTIVE         1024
+#define CLIENT_SECURE_CONNECTION 32768
+
+#define MIN(a,b) ((a)<(b)?(a):(b))
+#define ABS(a) (((a)>0)?(a):0)
+
+//MySQL commands
+#define COM_QUIT  0x01 //Exit
+#define COM_QUERY 0x03 //Execute an SQL query
+
+//#define htons( x ) ( (( x << 8 ) & 0xFF00) | (( x >> 8 ) & 0x00FF) )
+#define ntohs( x ) (htons(x))
+
+/*#define htonl( x ) ( (( x << 24 ) & 0xFF000000)  \
+                   | (( x <<  8 ) & 0x00FF0000)  \
+                   | (( x >>  8 ) & 0x0000FF00)  \
+                   | (( x >> 24 ) & 0x000000FF)  )*/
+#define htonl( x ) (x)
+#define ntohl( x ) (htonl(x))
+
+MySQLClient::MySQLClient() : NetService(false) /*Not owned by the pool*/, m_pCbItem(NULL), m_pCbMeth(NULL), m_pCb(NULL),
+m_pTCPSocket(NULL), m_watchdog(), m_timeout(MYSQL_TIMEOUT_MS*1000), m_pDnsReq(NULL), m_closed(true), 
+m_host(), m_user(), m_password(), m_db(), m_state(MYSQL_CLOSED)
+{
+  m_buf = new byte[BUF_SIZE];
+  m_pPos = m_buf;
+  m_len = 0;
+  m_size = BUF_SIZE;
+}
+
+MySQLClient::~MySQLClient()
+{
+  close();
+  delete[] m_buf;
+}
+
+//High Level setup functions
+MySQLResult MySQLClient::open(Host& host, const string& user, const string& password, const string& db, void (*pMethod)(MySQLResult)) //Non blocking
+{
+  setOnResult(pMethod);
+  setup(host, user, password, db);
+  return MYSQL_PROCESSING;
+}
+
+#if 0 //Ref only
+template<class T> 
+MySQLResult MySQLClient::open(Host& host, const string& user, const string& password, const string& db, T* pItem, void (T::*pMethod)(MySQLResult)) //Non blocking
+{
+  setOnResult(pItem, pMethod);
+  setup(host, user, password, db);
+  return MYSQL_PROCESSING;
+}
+#endif
+
+MySQLResult MySQLClient::sql(string& sqlCommand)
+{
+  if(m_state!=MYSQL_COMMANDS)
+    return MYSQL_SETUP;
+  sendCommand(COM_QUERY, (byte*)sqlCommand.data(), sqlCommand.length());
+  return MYSQL_PROCESSING;
+}
+
+MySQLResult MySQLClient::exit()
+{
+  sendCommand(COM_QUIT, NULL, 0);
+  close();
+  return MYSQL_OK;
+}
+  
+void MySQLClient::setOnResult( void (*pMethod)(MySQLResult) )
+{
+  m_pCb = pMethod;
+  m_pCbItem = NULL;
+  m_pCbMeth = NULL;
+}
+
+#if 0 //Ref only
+template<class T> 
+void MySQLClient::setOnResult( T* pItem, void (T::*pMethod)(MySQLResult) )
+{
+  m_pCb = NULL;
+  m_pCbItem = (CDummy*) pItem;
+  m_pCbMeth = (void (CDummy::*)(MySQLResult)) pMethod;
+}
+#endif
+
+void MySQLClient::setTimeout(int ms)
+{
+  m_timeout = 1000*ms;
+}
+
+void MySQLClient::poll() //Called by NetServices
+{
+  if(m_closed)
+  {
+    return;
+  }
+  if(m_watchdog.read_us()>m_timeout)
+  {
+    onTimeout();
+  }
+}
+
+void MySQLClient::resetTimeout()
+{
+  m_watchdog.reset();
+  m_watchdog.start();
+}
+
+void MySQLClient::init()
+{
+  close(); //Remove previous elements
+  if(!m_closed) //Already opened
+    return;
+  m_state = MYSQL_HANDSHAKE;
+  m_pTCPSocket = new TCPSocket;
+  m_pTCPSocket->setOnEvent(this, &MySQLClient::onTCPSocketEvent);
+  m_closed = false;
+}
+
+void MySQLClient::close()
+{
+  if(m_closed)
+    return;
+  m_state = MYSQL_CLOSED;
+  m_closed = true; //Prevent recursive calling or calling on an object being destructed by someone else
+  m_watchdog.stop(); //Stop timeout
+  m_watchdog.reset();
+  m_pTCPSocket->resetOnEvent();
+  m_pTCPSocket->close();
+  delete m_pTCPSocket;
+  m_pTCPSocket = NULL;
+  if( m_pDnsReq )
+  {
+    m_pDnsReq->close();
+    delete m_pDnsReq;
+    m_pDnsReq = NULL;
+  }
+}
+
+void MySQLClient::setup(Host& host, const string& user, const string& password, const string& db) //Setup connection, make DNS Req if necessary
+{
+  init(); //Initialize client in known state, create socket
+  resetTimeout();
+  m_host = host;
+  if(!host.getPort())
+    host.setPort( MYSQL_PORT ); //Default port
+    
+  m_user = user;
+  m_password = password;
+  
+  m_db = db;
+  
+  IpAddr ip;
+  if( !host.getIp().isNull() )
+  {
+    connect();
+  }
+  else //Need to do a DNS Query...
+  {
+    DBG("\r\nDNS Query...\r\n");
+    m_pDnsReq = new DNSRequest();
+    m_pDnsReq->setOnReply(this, &MySQLClient::onDNSReply);
+    m_pDnsReq->resolve(&m_host);
+    DBG("\r\nMySQLClient : DNSRequest %p\r\n", m_pDnsReq);
+  }
+}
+
+void MySQLClient::connect() //Start Connection
+{
+  resetTimeout();
+  DBG("\r\nConnecting...\r\n");
+  m_pTCPSocket->connect(m_host);
+  m_packetId = 0;
+}
+
+void MySQLClient::handleHandshake()
+{
+  readData();
+  if( ! (( m_len > 1 ) && ( memchr( m_buf + 1, 0, m_len ) != NULL )) )
+  {
+    DBG("Connected but could not find pcsz...\n");
+    onResult(MYSQL_PRTCL);
+    return;
+  }
+  
+  DBG("Connected to server: %d bytes read ; Protocol version %d, mysql-%s.\n", m_len, m_buf[0], &m_buf[1]);
+  
+  m_pPos = (byte*) memchr( (char*)(m_buf + 1), 0, m_len ) + 1;
+  
+  sendAuth();
+}
+
+void MySQLClient::sendAuth()
+{
+  if( m_len - (m_pPos - m_buf) != 44)
+  {
+    //We only support protocol >= mysql-4.1
+    DBG("Message after pcsz has wrong len (%d != 44)...\n", m_len - (m_pPos - m_buf));
+    onResult(MYSQL_PRTCL);
+    return;
+  }
+   
+  uint16_t serverFlags = *((uint16_t*)&m_pPos[13]);
+  DBG("Server capabilities are %04X.\n", serverFlags);
+  
+  uint32_t clientFlags = CLIENT_CONNECT_WITH_DB | CLIENT_PROTOCOL_41 | CLIENT_SECURE_CONNECTION | CLIENT_INTERACTIVE;;
+  
+  //if(serverFlags & CLIENT_LONG_PASSWORD)
+  
+  DBG("Using auth 4.1+\n");
+  //Encrypt pw using scramble
+  byte scramble[20+20]={0};
+  memcpy(scramble, m_pPos+4, 8); 
+  memcpy(scramble+8, m_pPos+31, 12); // *(m_pPos+43) == 0 (zero-terminated char*)
+
+  byte stage1_hash[20] = {0};
+  sha1( (byte*)m_password.data(), m_password.length(), stage1_hash );
+
+  sha1( stage1_hash, 20, ((byte*)scramble + 20) );
+
+  byte token[20] = {0};
+  sha1( scramble, 40, token );
+
+  for(int i=0;i<20;i++)
+    token[i] = token[i] ^ stage1_hash[i];
+    
+  clientFlags |= CLIENT_LONG_PASSWORD;
+  
+  DBG("Building response\n"); 
+  //Build response
+
+  //BE
+  *((uint32_t*)&m_buf[0]) = htonl(clientFlags);
+  *((uint32_t*)&m_buf[4]) = BUF_SIZE; //Max packets size
+  m_buf[8] = 8; //latin1 charset
+  memset((char*)(m_buf+9),0,23);
+  strcpy((char*)(m_buf+32),m_user.c_str());
+  m_pPos = m_buf + 32 + m_user.length() + 1;
+  m_pPos[0] = 20;
+  memcpy((char*)&m_pPos[1],token,20);
+  strcpy((char*)(m_pPos+21),m_db.c_str());
+  m_len = 32 + m_user.length() + 1 + 21 + m_db.length() + 1;
+  
+  //Save first part of scramble in case we need it again
+  memcpy(&m_buf[BUF_SIZE-8], scramble, 8);
+
+  m_state = MYSQL_AUTH;
+  
+  DBG("Writing data\n"); 
+  writeData();
+}
+
+void MySQLClient::handleAuthResult()
+{
+  readData();
+  if(m_len==1 && *m_buf==0xfe)
+  {
+    //Re-send auth using 4.0- auth
+    sendAuth323();
+    return;
+  }
+  m_watchdog.stop(); //Stop timeout
+  m_watchdog.reset();
+  if(m_len<2)
+  {
+    DBG("Response too short..\n");
+    onResult(MYSQL_PRTCL);
+    return;
+  }
+  DBG("RC=%d ",m_buf[0]);
+  if(m_buf[0]==0)
+  {
+    m_buf[m_len] = 0;
+    m_pPos = m_buf + 1;
+    m_pPos += m_buf[1] +1;
+    m_pPos += m_pPos[0];
+    m_pPos += 1;
+    DBG("(OK) : Server status %d, Message : %s\n", *((uint16_t*)&m_pPos[0]), m_pPos+4);
+    onResult(MYSQL_OK);
+  }
+  else
+  {
+    m_buf[m_len] = 0;
+    DBG("(Error %d) : %s\n", *((uint16_t*)&m_buf[1]), &m_buf[9]); //LE
+    onResult(MYSQL_AUTHFAILED);
+    return;
+  }
+  m_state = MYSQL_COMMANDS;
+}
+
+void MySQLClient::sendAuth323()
+{
+  DBG("Using auth 4.0-\n");
+  byte scramble[8]={0};
+  
+  memcpy(scramble, &m_buf[BUF_SIZE-8], 8); //Recover scramble
+  
+  //memcpy(scramble+8, m_pPos+31, 12); // *(m_pPos+43) == 0 (zero-terminated char*)
+  
+  byte token[9]={0};
+  
+  scramble_323((char*)token, (const char*)scramble, m_password.c_str());
+  
+  DBG("Building response\n"); 
+  //Build response
+  
+  memcpy((char*)m_buf,token,9);
+  m_len = 9;
+
+  #if 0
+  *((uint32_t*)&m_buf[0]) = htonl(clientFlags);
+  *((uint32_t*)&m_buf[4]) = BUF_SIZE; //Max packets size
+  m_buf[8] = 8; //latin1 charset
+  memset((char*)(m_buf+9),0,23);
+  strcpy((char*)(m_buf+32),m_user.c_str());
+  m_pPos = m_buf + 32 + m_user.length() + 1;
+  m_pPos[0] = 8;
+  memcpy((char*)&m_pPos[1],token+1,8);
+  strcpy((char*)(m_pPos+9),m_db.c_str());
+  m_len = 32 + m_user.length() + 1 + 9 + m_db.length() + 1;
+  #endif
+  
+  DBG("Writing data\n"); 
+  writeData();
+}
+
+void MySQLClient::sendCommand(byte command, byte* arg, int len)
+{
+  DBG("Sending command %d, payload of len %d\n", command, len);
+  m_packetId=0;//Reset packet ID (New sequence)
+  m_buf[0] = command;
+  memcpy(&m_buf[1], arg, len);
+  m_len = 1 + len;
+  writeData();
+  m_watchdog.start();
+}
+
+void MySQLClient::handleCommandResult()
+{
+  readData();
+  m_watchdog.stop(); //Stop timeout
+  m_watchdog.reset();
+  if(m_len<2)
+  {
+    DBG("Response too short..\n");
+    onResult(MYSQL_PRTCL);
+    return;
+  }
+  DBG("RC=%d ",m_buf[0]);
+  if(m_buf[0]==0)
+  {
+    DBG("(OK)\n");
+    onResult(MYSQL_OK);
+  }
+  else
+  {
+    m_buf[m_len] = 0;
+    DBG("(SQL Error %d) : %s\n", *((uint16_t*)&m_buf[1]), &m_buf[9]); //LE
+    onResult(MYSQL_SQL);
+    return;
+  }
+}
+
+void MySQLClient::readData() //Copy to buf
+{
+  byte head[4];
+  int ret = m_pTCPSocket->recv((char*)head, 4); //Packet header
+  m_len = *((uint16_t*)&head[0]);
+  m_packetId = head[3];
+  DBG("Packet Id %d of length %d\n", head[3], m_len);
+  m_packetId++;
+  if(ret>0)
+    ret = m_pTCPSocket->recv((char*)m_buf, m_len);
+  if(ret < 0)//Error
+  {
+    onResult(MYSQL_CONN);
+    return;
+  }
+  if(ret < m_len)
+  {
+    DBG("WARN: Incomplete packet\n");
+  }
+  m_len = ret;
+}
+
+void MySQLClient::writeData() //Copy from buf
+{
+  byte head[4] = { 0 };
+  *((uint16_t*)&head[0]) = m_len;
+  head[3] = m_packetId;
+  DBG("Packet Id %d\n", head[3]);
+  m_packetId++;
+  int ret = m_pTCPSocket->send((char*)head, 4); //Packet header
+  if(ret>0)
+    ret = m_pTCPSocket->send((char*)m_buf, m_len);
+  if(ret < 0)//Error
+  {
+    onResult(MYSQL_CONN);
+    return;
+  }
+  m_len = 0;//FIXME... incomplete packets handling
+}
+
+void MySQLClient::onTCPSocketEvent(TCPSocketEvent e)
+{
+  DBG("\r\nEvent %d in MySQLClient::onTCPSocketEvent()\r\n", e);
+
+  if(m_closed)
+  {
+    DBG("\r\nWARN: Discarded\r\n");
+    return;
+  }
+  
+  switch(e)
+  {
+  case TCPSOCKET_READABLE: //Incoming data
+    resetTimeout();
+    if(m_state == MYSQL_HANDSHAKE)
+      handleHandshake();
+    else if(m_state == MYSQL_AUTH)
+      handleAuthResult();
+    else if(m_state == MYSQL_COMMANDS)
+      handleCommandResult();
+    break;
+  case TCPSOCKET_WRITEABLE: //We can send data
+    resetTimeout();
+    break;
+  case TCPSOCKET_CONNECTED: //Connected, wait for handshake packet
+    resetTimeout();
+    break;
+  case TCPSOCKET_CONTIMEOUT:
+  case TCPSOCKET_CONRST:
+  case TCPSOCKET_CONABRT:
+  case TCPSOCKET_ERROR:
+    DBG("\r\nConnection error.\r\n");
+    onResult(MYSQL_CONN);
+  case TCPSOCKET_DISCONNECTED:
+    //There might still be some data available for reading
+    //So if we are in a reading state, do not close the socket yet
+    if(m_state != MYSQL_CLOSED)
+    {
+      onResult(MYSQL_CONN);
+    }
+    DBG("\r\nConnection closed by remote host.\r\n");
+    break;
+  }
+}
+
+void MySQLClient::onDNSReply(DNSReply r)
+{
+  if(m_closed)
+  {
+    DBG("\r\nWARN: Discarded\r\n");
+    return;
+  }
+  
+  if( r != DNS_FOUND )
+  {
+    DBG("\r\nCould not resolve hostname.\r\n");
+    onResult(MYSQL_DNS);
+    return;
+  }
+  
+  DBG("\r\nDNS Resolved to %d.%d.%d.%d.\r\n",m_host.getIp()[0],m_host.getIp()[1],m_host.getIp()[2],m_host.getIp()[3]);
+  //If no error, m_host has been updated by m_pDnsReq so we're set to go !
+  m_pDnsReq->close();
+  delete m_pDnsReq;
+  m_pDnsReq = NULL;
+  connect();
+}
+
+void MySQLClient::onResult(MySQLResult r) //Called when exchange completed or on failure
+{
+  if(m_pCbItem && m_pCbMeth)
+    (m_pCbItem->*m_pCbMeth)(r);
+  else if(m_pCb)
+    m_pCb(r);
+    
+  if( (r==MYSQL_DNS) || (r==MYSQL_PRTCL) || (r==MYSQL_AUTHFAILED) || (r==MYSQL_TIMEOUT) || (r==MYSQL_CONN) ) //Fatal error, close connection
+    close();
+}
+
+void MySQLClient::onTimeout() //Connection has timed out
+{
+  DBG("\r\nTimed out.\n");
+  onResult(MYSQL_DNS);
+  close();
+}