webserver.c

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/*********************************************************************************

 Copyright 2006-2008 MakingThings

 Licensed under the Apache License, 
 Version 2.0 (the "License"); you may not use this file except in compliance 
 with the License. You may obtain a copy of the License at

 http://www.apache.org/licenses/LICENSE-2.0 
 
 Unless required by applicable law or agreed to in writing, software distributed
 under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
 CONDITIONS OF ANY KIND, either express or implied. See the License for
 the specific language governing permissions and limitations under the License.

*********************************************************************************/


/** \file webserver.c 
  Functions for implementing a WebServer on the Make Controller Board.
*/

#include "config.h" // MakingThings.
#ifdef MAKE_CTRL_NETWORK

/* Standard includes. */
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>

#include "network.h"

#define HANDLERS_MAX        5
#define REQUEST_SIZE_MAX  256
#define RESPONSE_SIZE_MAX 1000
#define HTTP_OK "HTTP/1.0 200 OK\r\nContent-type: "
#define HTTP_CONTENT_HTML "text/html\r\n\r\n"
#define HTTP_CONTENT_PLAIN "text/plain\r\n\r\n"
#define HTTP_PORT   ( 80 )

#define HTML_OS_START \
"<BR>Make Magazine - MakingThings<BR><H1>MAKE Controller Kit</H1>"

void WebServerTask( void *p );

typedef struct WebServerHandlerS
{
  char* address;
  int (*handler)( char* requestType, char* address,  char* requestBuffer, int requestMaxSize, void* socket, char* buffer, int len ); 
} WebServerHandler;

typedef struct WebServerHandlersS
{
  int count;
  WebServerHandler handlers[ HANDLERS_MAX ];
} WebServerHandlers_;

WebServerHandlers_* WebServerHandlers = NULL;

typedef struct WebServerS
{
  int hits;
  void* serverTask;
  void *serverSocket;
  void *requestSocket;
  int listenPort;
  bool changeListenPort;
  char request[ REQUEST_SIZE_MAX ];
  char response[ RESPONSE_SIZE_MAX ];
} WebServer_;

WebServer_* WebServer = NULL;

#include "webserver.h"
#include "analogin.h"
#include "system.h"

#include "FreeRTOS.h"
#include "task.h"

int TestHandler( char* requestType, char* address, char* requestBuffer, int requestMaxSize, void* socket, char* buffer, int len );

static int WebServer_WriteResponseOk_( char* content, void* socket );


/** \defgroup webserver Web Server
  A simple Web Server

  This Web Server implementation is based on the \ref ServerSocket and \ref Socket functions defined
  in \ref Sockets.  When started, a ServerSocket is opened and set to listen on port 80.

  When the server receives a request, it checks the incoming address against a list of handlers.
  If the request address matches, the handler is invoked and checking stops.  Users can add their own
  handlers to return custom information - see WebServer_Route().  Most of the rest of the WebServer 
  system provides helpful functions for generating and parsing HTML.

  There is a single default/test handler that will handle any requests that are not otherwise handled.  This
  is about the simplest demo possible of how to write a handler - it simply prints out some text and a count
  of how pages it has served.  There are more handler examples further down this page, and in the mcbuilder 
  examples.  Take a look at TestHandler() in webserver.c to see its source.

  To access the web server type the IP address of your board into a web browser, optionally followed by
  the address of any handlers you've registered, ie \b 192.168.1.200/myhandler.  

  \ingroup Libraries
  @{
*/

/**
  Start the WebServer up, listening on port 80.
  See WebServer_Route() for info on how to register handlers for certain requests.
  @param active An integer specifying the active state - 1 (on) or 0 (off).
  @return CONTROLLER_OK (0) on success or the appropriate error if not

  \b Example
  \code
  // fire up the webserver
  WebServer_SetActive(true);
  \endcode
*/
int WebServer_SetActive( int active )
{
  if ( active )
  {
    if ( WebServer == NULL )
    {
      WebServer = MallocWait( sizeof( WebServer_ ), 100 );
      WebServer->hits = 0;
      WebServer->serverSocket = NULL;
      WebServer->requestSocket = NULL;
      WebServer->changeListenPort = false;
      WebServer->listenPort = HTTP_PORT; // default to 80
      #ifdef CROSSWORKS_BUILD
      int stacksize = 800;
      #else
      int stacksize = 1800;
      #endif // CROSSWORKS_BUILD
      WebServer->serverTask = TaskCreate( WebServerTask, "WebServ", stacksize, NULL, 4 );
      if ( WebServer->serverTask == NULL )
      {
        Free( WebServer );
        WebServer = NULL;
        return CONTROLLER_ERROR_CANT_START_TASK;
      }
    }
  }
  else
  {
    if( WebServer != NULL )
    {
      if ( WebServer->serverTask != NULL )
        TaskDelete( WebServer->serverTask );
      if ( WebServer->serverSocket != NULL )
        ServerSocketClose( WebServer->serverSocket );
      if ( WebServer->requestSocket != NULL )
        SocketClose( WebServer->requestSocket );
  
      Free( WebServer );
      WebServer = NULL;
    }
  }
  return CONTROLLER_OK;
}

/**
  Read the active state of the WebServer subsystem.
  @return State - 1/non-zero (on) or 0 (off).
*/
int  WebServer_GetActive( void )
{
  return ( WebServer != NULL ) ? 1 : 0;
}

/**
  Set the port that the webserver should listen on for new connections.
  Note that this does not immediately take effect - because the webserver
  (if it's open) is already listening on a port, it will only take effect
  after it serves one last request on that port.
  @param port The new port to listen on.
  @return 0 on success.

  \b Example
  \code
  // listen on a non-standard port for HTTP
  WebServer_SetListenPort(8080);
  \endcode
*/
int WebServer_SetListenPort( int port )
{
  WebServer->listenPort = port;
  return CONTROLLER_OK;
}

/**
  Get the port that the webserver is currently listening on.
  @return The port number.

  \b Example
  \code
  int currentPort = WebServer_GetListenPort( );
  \endcode
*/
int WebServer_GetListenPort( void )
{
  return WebServer->listenPort;
}

/**
  Adds a route handler to the WebServer.

  This function binds an address fragment (e.g. "/", "/adcs", etc.) to a handler
  that will be called when the address matches.  Matching ignores characters in the 
  incoming address that are beyond the end of the address specified to this function.
  The first function to match the address will receive all the traffic and no more 
  handlers will be checked.  Thus if a handler is set up to match "/images" it will match
  "/images" and "/images/logo.png" and so on.  Also if there is a subseqent handler 
  set to match "/images/diagram" it will never be called since the prior handler
  will match the entire "/images" space.  You can register your handlers prior to firing up
  the webserver system.

  The handler will be called with the request type specified (usually "GET" or  "POST"), 
  the incoming address ( "/device/0", "/images/logo.png", etc.) A buffer (and max length) is passed in that
  can be used to receive the rest of the message if necessary. Then there will be 
  the socket which will take the response and a helpful large buffer or specified length
  which can be used to build strings.

  At the time the handler is called, only the first line of the request has been read.  It is used
  to determine the request type and the address requested.  If you need to process the request further
  its contents may be read into a buffer (the request buffer passed in is good once the request type 
  address have been used since they're in there initially).  The SocketReadLine( ) function is 
  convenient to read a line of the request at a time.

  The handler itself must first write the response using one of WebServer_WriteResponseOkHTML() for
  sending HTML or WebServer_WriteResponseOkPlain() for returning plain text.  
  These send the appropriate HTTP header (for example "HTTP/1.0 200 OK\r\nContent-type:text/html\r\n\r\n").
  All responses may be simply written to the Socket, but several helpers are provided to assist in the 
  construction of simple web pages (for example WebServer_WriteHeader(), WebServer_WriteBodyStart(), etc.). 
  
  The handler should return non-zero if it handled the response appropriately or 0 if not, in which case
  the webserver will check for matches with other handlers that can handle it.
  @param address An string specify the addresses to match.
  @param handler pointer to a handler function that will be called when the address is matched.
  @return CONTROLLER_OK (=0) on success or the appropriate error if not

  Here is an example of how to register a handler:
  \code
// now requests at MyBoardsIPAddress/my/handler will be handled by MyHandler
WebServer_Route( "/my/handler", MyHandler );
  \endcode

  And here is an example handler, printing out some simple info in response to any request.
  \code
int MyHandler( char* requestType, char* address, char* requestBuffer, int requestMaxSize, 
                 void* socket, char* buffer, int len )
{
  (void)requestType;
  (void)address;
  WebServer_WriteResponseOkHTML( socket );
  WebServer_WriteHeader( true, socket, buffer, len );
  WebServer_WriteBodyStart( address, socket, buffer, len );
  snprintf( buffer, len, "<H1>TEST</H1>%d hits", WebServer->hits );
  SocketWrite( socket, buffer, strlen( buffer ) );
  WebServer_WriteBodyEnd( socket );
  return true;
}
  \endcode
*/
int WebServer_Route( char* address, 
                    int (*handler)( char* requestType, char* address, char* requestBuffer, 
                    int requestMaxSize, void* socket, char* buffer, int len ) )
{
  if ( WebServerHandlers == NULL )
  {
    WebServerHandlers = MallocWait( sizeof( WebServerHandlers_ ), 100 );    
    if ( WebServerHandlers != NULL )
      WebServerHandlers->count = 0;
  }
  if ( WebServerHandlers != NULL )
  {
    if ( WebServerHandlers->count < HANDLERS_MAX )
    {
      WebServerHandler* hp = &WebServerHandlers->handlers[ WebServerHandlers->count++ ];
      hp->address = address;
      hp->handler = handler;
      return CONTROLLER_OK;
    }
   return CONTROLLER_ERROR_INSUFFICIENT_RESOURCES;
  }

  return CONTROLLER_ERROR_NOT_OPEN;
}


/**
  Writes the HTTP OK message and sets the content type to HTML.
  This will typically be the first thing you write out in your handler.
  Also see WebServer_WriteResponseOkPlain() to set your response type to plain text.
  @param socket The socket to write to
  @return non-zero on success, zero on failure.

  \b Example
  \code
  int MyRequestHandler( char* requestType, char* address, char* requestBuffer, 
                      int requestMaxSize, void* socket, char* buffer, int len )
  {
    WebServer_WriteResponseOkHTML(socket); // write the response out first
    // ... continue processing ...
  }
  \endcode
*/
int WebServer_WriteResponseOkHTML( void* socket )
{
  //return WebServer_WriteResponseOk_( socket, HTTP_CONTENT_HTML );
  int written = 0;
  int ret = 0;
  ret = SocketWrite( socket, HTTP_OK, strlen( HTTP_OK ) );
  if( !ret )
    return 0;
  else
    written += ret;

  ret = SocketWrite( socket, HTTP_CONTENT_HTML, strlen( HTTP_CONTENT_HTML ) );
  if( !ret )
    return 0;
  else
    written += ret;

  return written;
}
  
/**
  Writes the HTTP OK message and sets the content type to plain text.
  This will typically be the first thing you write out in your handler.
  Also see WebServer_WriteResponseOkHTML() to set your response type to HTML.
  @param socket The socket to write to.
  @return non-zero on success, zero on failure.

  \b Example
  \code
  int MyRequestHandler( char* requestType, char* address, char* requestBuffer, 
                      int requestMaxSize, void* socket, char* buffer, int len )
  {
    WebServer_WriteResponseOkPlain(socket); // write the response out first
    // ... continue processing ...
  }
  \endcode
*/
int WebServer_WriteResponseOkPlain( void* socket )
{
  return WebServer_WriteResponseOk_( socket, HTTP_CONTENT_PLAIN );
}

/**
  Writes the HTML header.
  Should be preceded by a call to WebServer_WriteResponseOkHTML(). 
  See WebServer_Route() for a more complete example.
  @param includeCSS A flag signalling the inclusion of a very simple CSS header 
  refining h1 and body text slightly.
  @param socket The socket to write to
  @param buffer Helper buffer which the function can use.  Should be at least 300 bytes.
  @param len Helper buffer length
  @return non-zero on success, zero on failure.
  \todo more parameterization

  \b Example
  \code
  int MyRequestHandler( char* requestType, char* address, char* requestBuffer, 
                      int requestMaxSize, void* socket, char* buffer, int len )
  {
    // ... usually write out the OK response first ...
    WebServer_WriteHeader(true, socket, buffer, len); // write the header, including simple CSS
    // ... continue processing ...
  }
  \endcode
*/
int WebServer_WriteHeader( int includeCSS, void* socket, char* buffer, int len )
{
  (void)buffer;
  (void)len;
  char* headerStart = "<HTML>\r\n<HEAD>";
  char* headerEnd = "\r\n</HEAD>";
  char* style = "\r\n<STYLE type=\"text/css\"><!--\
body { font-family: Arial, Helvetica, sans-serif; } \
h1 { font-family: Arial, Helvetica, sans-serif; font-weight: bold; }\
--></STYLE>";

  strcpy( buffer, headerStart );
  if ( includeCSS )
    strcat( buffer, style );
  strcat( buffer, headerEnd );
  return SocketWrite( socket, buffer, strlen( buffer ) );
}

/**
  Writes the start of the BODY tag.
  Should be preceded by a call to WebServer_WriteHeader().  Also writes a light grey background.
  You can optionally specify that you'd like the page to automatically refresh itself once 
  a second by passing in the address to reload to \b reloadAddress.  See WebServer_Route() for a more complete example.
  @param reloadAddress A string signaling the address of a 1 second reload request.  If it is NULL, no reload is requested.
  @param socket The socket to write to.
  @param buffer Helper buffer which the function can use.  Should be at least 300 bytes.  This is usually the buffer
  passed into your handler as \b buffer.
  @param len Helper buffer length.  Also usually passed into your handler as \b len.
  \todo more parameterization of the tag

  \b Example
  \code
  int MyRequestHandler( char* requestType, char* address, char* requestBuffer, 
                      int requestMaxSize, void* socket, char* buffer, int len )
  {
    // ... usually write out the OK response and the header first ...
    WebServer_WriteBodyStart(0, socket, buffer, len); // write the body start, with no reload
    // ... continue processing ...
  }
  \endcode
*/
int WebServer_WriteBodyStart( char* reloadAddress, void* socket, char* buffer, int len )
{
  (void)buffer;
  (void)len;
  char* bodyStart = "\r\n<BODY";
  char* bodyEnd = " bgcolor=\"#eeeeee\">\r\n";

  char* reloadStart = " onLoad=\"window.setTimeout(&quot;location.href='";
  char* reloadEnd = "'&quot;,1000)\"";
  strcpy( buffer, bodyStart );
  if ( reloadAddress )
  {
    strcat( buffer, reloadStart  );
    strcat( buffer, reloadAddress  );
    strcat( buffer, reloadEnd  );
  }
  strcat( buffer, bodyEnd  );
  return SocketWrite( socket, buffer, strlen( buffer ) );
}

/**
  Writes the end of the Body tag - and the final end of HTML tag.
  Should be preceded by writes to the socket with the content of the page - 
  this is often the last thing done in a handler.  See WebServer_Route() for a more complete example.
  @param socket The socket to write to
  @return non-zero on success, zero on failure.

  \b Example
  \code
  int MyRequestHandler( char* requestType, char* address, char* requestBuffer, 
                      int requestMaxSize, void* socket, char* buffer, int len )
  {
    // ... other code actually doing interesting things ...
    WebServer_WriteBodyEnd(socket); // now we're all done
    return 1;
  }
  \endcode
*/
int WebServer_WriteBodyEnd( void* socket )
{
  char* bodyEnd = "\r\n</BODY>\r\n</HTML>";

  return SocketWrite( socket, bodyEnd, strlen( bodyEnd ) );
}

/**
  Set the data of an incoming HTTP POST request to the given buffer.
  This is designed to be used from within a custom handler.  An incoming HTTP request will have some number of
  lines of header information, and this function will read through them until getting to the body of the message.
  It will then store the contents of the body in the given buffer, null-terminating the end of the data.

  It's usually convenient to set the POST data in the requestBuffer since it's already allocated.

  \b Example
  \code
int MyRequestHandler( char* requestType, char* address, char* requestBuffer, 
                      int requestMaxSize, void* socket, char* buffer, int len )
{
  // ... other setup here ...

  if ( strncmp( requestType, "POST", 4 ) == 0 ) // if the request is indeed a POST
  {
    if( WebServer_GetPostData( socket, requestBuffer, requestMaxSize ) ) // set the POST data in the requestBuffer
    {
      // process the data in any way you like.
      // here, we're expecting a form and we want to grab the info out of it
      formElements = WebServer_ParseFormElements( requestBuffer, &form );
    }
  }

  // ... write out the response here ...
}
  \endcode
  @param socket The socket from the incoming request
  @param requestBuffer A pointer to the buffer to store the data in.
  @param maxSize The maximum amount of data to be placed in the buffer.
  @return true on success, false on failure
*/
bool WebServer_GetPostData( void *socket, char *requestBuffer, int maxSize )
{
  bool retval = false;
  // keep reading lines of the HTTP header until we get CRLF which signifies the end of the
  // header and the start of the body data.  If we see the contentlength along the way, keep that.
  int contentLength = 0;
  int bufferLength = 0;
  while ( ( bufferLength = SocketReadLine( socket, requestBuffer, maxSize ) ) )
  {
    if ( strncmp( requestBuffer, "\r\n", 2 ) == 0 )
      break;
    if ( strncmp( requestBuffer, "Content-Length", 14 ) == 0 )
      contentLength = atoi( &requestBuffer[ 15 ] );
  }
  
  // now we should be down to the HTTP POST data
  // if there's any data, get up into it
  if ( contentLength > 0 && bufferLength > 0 )
  {  
    int bufferRead = 0;
    int lengthToRead;
    int avail = SocketBytesAvailable(socket);
    if(avail > maxSize)
      lengthToRead = maxSize - 1;
    else
      lengthToRead = avail;
    char *rbp = requestBuffer;
    // read all that the socket has to offer...may come in chunks, so keep going until there's none left
    while ( ( bufferLength = SocketRead( socket, rbp, lengthToRead ) ) )
    {
      bufferRead += bufferLength;
      rbp += bufferLength;
      lengthToRead -= bufferLength;
      if ( bufferRead >= contentLength )
        break;
    }
    requestBuffer[ bufferRead ] = 0; // null-terminate the request
    retval = true;
  }
  return retval;
}

/**
  Extract the elements of an HTML form into key/value pairs.
  This is designed to be used from within a custom handler.  HTML forms can be sent via either the HTTP GET 
  or POST methods.  The \b request parameter must be set to the start of the form data, which is 
  located in a different place for each method.  In the \b GET case, we need to check if there are any 
  form elements, as indicated by a \b ? after the URL address.  In the \b POST case, we can use 
  WebServer_GetPostData() to find the beginning of the POST data for us.

  Note that the HtmlForm structure will simply point to the elements in the request buffer, so as soon as
  the buffer is deleted or out of scope, the form data is no longer valid.

  \b Example
  \code
int MyRequestHandler( char* requestType, char* address, char* requestBuffer, 
                      int requestMaxSize, void* socket, char* buffer, int len )
{
  // ... other setup here ...
  
  int formElements = 0;
  HtmlForm form;
  form.count = 0;
  
  // determine the kind of request - GET or POST
  if ( strncmp( requestType, "GET", 3 ) == 0 )
  {
    char *p = strchr( requestBuffer, '?' ); // if GET, see if there's a ?
    if( p != NULL ) // if we didn't find a ?, there were no form elements
      formElements = WebServer_ParseFormElements( p+1, &form );
    // we have to send "p + 1" since the form data starts right after the ?
  }
  else if ( strncmp( requestType, "POST", 4 ) == 0 )
  {
    // make sure we're pointing at the POST data and if it looks good, process it
    if( WebServer_GetPostData( socket, requestBuffer, requestMaxSize ) )
      formElements = WebServer_ParseFormElements( requestBuffer, &form );
  }

  // ... write out the response here ...
}
  \endcode
  @param request A pointer to the form data
  @param form The HtmlForm structure to populate with elements
  @return The number of form elements found
*/
int WebServer_ParseFormElements( char *request, HtmlForm *form )
{
  int count = 0;
  bool cont = true;
  char *p = request;
  char* endp;

  do
  {
    endp = strchr( p, '=' );
    *endp = 0;
    form->elements[form->count].key = p;
    
    p = ++endp;
    endp = strchr( p, '&' ); // look for the next element
    if( endp == NULL ) // there is no next element, do this one and then be done
    {
      endp = strchr( p, 0 );
      cont = false;
    }
    *endp = 0;

    // if the value was empty, we'll either get the & if there are more elements, or 0 if we're at the end
    if( *(p+1) == '&' || *(p+1) == 0 )
      form->elements[form->count].value = 0;
    else
      form->elements[form->count].value = p;
    p = ++endp;
  
    form->count++;
    count++;
  } while( cont == true );

  return count;
}

/** @}
*/

int TestHandler( char* requestType, char* address, char* requestBuffer, int requestMaxSize, void* socket, char* buffer, int len )
{
  (void)requestType;
  (void)address;
  (void)requestBuffer;
  (void)requestMaxSize;
  WebServer_WriteResponseOkHTML( socket );
  WebServer_WriteHeader( true, socket, buffer, len );
  WebServer_WriteBodyStart( address, socket, buffer, len );
  snprintf( buffer, len, "<H1>Make Controller Web Server Test</H1> %d happy pages served...", WebServer->hits );
  SocketWrite( socket, buffer, strlen( buffer ) );
  WebServer_WriteBodyEnd( socket );
  return true;
}

void WebServer_Demo( char* requestType, char* address, char* requestBuffer, int requestMaxSize, void* socket, char* buffer, int len );
static void WebServer_ProcessRequest( void* requestSocket );
static void WebServer_CreateServerSocket( void );
static char* WebServer_GetRequestAddress( char* request, int length, char** requestType );

void WebServer_ProcessRequest( void* requestSocket )
{
  char* requestType = 0;
  char* address = 0;
  int i;
  int responded;

  SocketReadLine( requestSocket, WebServer->request, REQUEST_SIZE_MAX ); 
  address = WebServer_GetRequestAddress( WebServer->request, REQUEST_SIZE_MAX, &requestType );

  responded = false;
  if ( WebServerHandlers != NULL )
  {
    for ( i = 0; i < WebServerHandlers->count; i++ )
    {
      WebServerHandler* hp = &WebServerHandlers->handlers[ i ];
      if ( strncmp( hp->address, address, strlen( hp->address ) ) == 0 )
      {
        responded = (*hp->handler)( requestType, address, WebServer->request, REQUEST_SIZE_MAX, requestSocket, WebServer->response, RESPONSE_SIZE_MAX );
        if ( responded )
          break;
      }
    }
  }
  if(!responded)
    TestHandler(requestType, address, WebServer->request, REQUEST_SIZE_MAX, requestSocket, WebServer->response, RESPONSE_SIZE_MAX);

  SocketClose( requestSocket );
}

void WebServer_Demo( char* requestType, char* address, char* requestBuffer, int requestMaxSize, void* socket, char* buffer, int len )
{
  (void)address;
  char temp[100];

  if( !WebServer_WriteResponseOkHTML( socket ) )
    return;

  if( !WebServer_WriteHeader( true, socket, buffer, len ) )
    return;

  if( !WebServer_WriteBodyStart( 0, socket, buffer, len ) )
    return;
  
  int formElements = 0;
  HtmlForm form;
  form.count = 0;
  
  // if this request is an HTTP GET
  if ( strncmp( requestType, "GET", 3 ) == 0 )
  {
    char *p = strchr( requestBuffer, '?' );
    if( p != NULL ) // if we didn't find a ?, then there were no form elements
      formElements = WebServer_ParseFormElements( p+1, &form );
  }
  
  // if this request is an HTTP POST
  if ( strncmp( requestType, "POST", 4 ) == 0 )
  {
    // make sure we're pointing at the POST data and if it looks good, process it
    if( WebServer_GetPostData( socket, requestBuffer, requestMaxSize ) )
      formElements = WebServer_ParseFormElements( requestBuffer, &form ); // grab the data out of the form
  }
  
  strcat( buffer, "<form method=\"POST\">" );
  strcat( buffer, "App LED 0: <input type=\"checkbox\" name=\"appled0\"><br>" );
  strcat( buffer, "App LED 1: <input type=\"checkbox\" name=\"appled1\"><br>" );
  strcat( buffer, "App LED 2: <input type=\"checkbox\" name=\"appled2\"><br>" );
  strcat( buffer, "App LED 3: <input type=\"checkbox\" name=\"appled3\"><br>" );
  strcat( buffer, "<p></p>" ); 
  strcat( buffer, "<input type=\"submit\" value=\"Submit\">" );
  strcat( buffer, "</form>" );
  
  int i, j;
  for( j = 0; j < 4; j++ )
  {
    int value = 0;
    snprintf( temp, 100, "appled%d", j );
    for( i = 0; i < formElements; i++ )
    {
      if( strcmp( temp, form.elements[i].key ) == 0 )
        value = 1;
    }
    //AppLed_SetState( j, value );
  }
  
  // Write out the dynamically generated page.
  if( !SocketWrite( socket, buffer, strlen( buffer ) ) )
    return;
  
  WebServer_WriteBodyEnd( socket );
}

void WebServerTask( void *p )
{
  (void)p;

  // Try to create a socket on the appropriate port
  WebServer_CreateServerSocket();

  while( 1 )
  {
    if(WebServer->changeListenPort == true)
    {
      WebServer_CreateServerSocket();
      WebServer->changeListenPort = false;
    }
    /* Wait for connection. */
    WebServer->requestSocket = ServerSocketAccept( WebServer->serverSocket );
    
    if ( WebServer->requestSocket != NULL )
    {
      WebServer->hits++;
      WebServer_ProcessRequest( WebServer->requestSocket );
      WebServer->requestSocket = NULL;
    }
    Sleep( 5 );
  }
}

/*
  Create a new ServerSocket on the appropriate listenPort
*/
static void WebServer_CreateServerSocket( )
{
  if(WebServer->serverSocket)
  {
    SocketClose(WebServer->serverSocket);
    WebServer->serverSocket = NULL;
  }
  while( WebServer->serverSocket == NULL )
  { 
    WebServer->serverSocket = ServerSocket( WebServer->listenPort );
    if ( WebServer->serverSocket == NULL )
      Sleep( 1000 );
  }
}

static int WebServer_WriteResponseOk_( char* contentType, void* socket )
{
  int written = 0;
  written += SocketWrite( socket, HTTP_OK, strlen( HTTP_OK ) );
  written += SocketWrite( socket, contentType, strlen( contentType ) );
  return written;
}

char* WebServer_GetRequestAddress( char* request, int length, char** requestType  )
{
  char *last = request + length;
  *requestType = NULL;
  char* address = NULL;

  // Skip any initial spaces
  while( *request == ' ' )
    request++;

  if ( request > last )
    return address;

  *requestType = request;

  // Skip the request type
  while ( *request != ' ' )
    request++;

  if ( request > last )
    return address;

  // Skip any subsequent spaces
  while( *request == ' ' )
    request++;

  if ( request > last )
    return address;

  address = request;

  while( !isspace( *request ) )
    request++;
  
  if ( request < last )
    *request = 0;

  return address;
}

#ifdef OSC // Webserver OSC interface

/** \defgroup webserverosc Web Server - OSC
  Configure the Web Server  via OSC.
  \ingroup OSC

  \section devices Devices
    There is only one Web Server system, so a device index is not used.
   
  \section properties Properties
  The Web Server system has the following properties
  - active
  - listenport

  \section details Property Details

  \b Active

  The \b active property sets whether the web server on the Make Controller is running or not.
  The default web server does not really do anything too interesting, but provides a count of the
  number of requests it has served.  You can access the web server by typing the board's IP address
  into your favorite browser.  You can check the board's IP address in mchelper.

  To turn the web server on, send the message
  \code /webserver/active 1 \endcode
  then enter the board's IP address into the address bar of your favorite web browser.  Send the message
  \code /network/webserver 0 \endcode
  to turn the webserver off.

  <b> Listen Port </b>

  The \b listenport property sets which port the web server should listen on for incoming requests.  By default
  this is set to 80, the standard port for HTTP.

  To listen on port 8080, send the message
  \code /webserver/listenport 8080 \endcode

  Note that the server will most likely already be listening on the previous port, and it won't update its port
  until it serves that last request it's waiting for.
*/

#include "osc.h"
static char* WebServerOsc_Name = "webserver";
static char* WebServerOsc_PropertyNames[] = { "active", "listenport", 0 }; // must have a trailing 0

int WebServerOsc_PropertySet( int value, int property );
int WebServerOsc_PropertyGet( int property );

const char* WebServerOsc_GetName( void )
{
  return WebServerOsc_Name;
}

int WebServerOsc_ReceiveMessage( int channel, char* message, int length )
{
  int status = Osc_IntReceiverHelper( channel, message, length, 
                                      WebServerOsc_Name,
                                      WebServerOsc_PropertySet, WebServerOsc_PropertyGet, 
                                      WebServerOsc_PropertyNames );

  if ( status != CONTROLLER_OK )
    return Osc_SendError( channel, WebServerOsc_Name, status );
  return CONTROLLER_OK;
}

// Set the index LED, property with the value
int WebServerOsc_PropertySet( int property, int value )
{
  switch ( property )
  {
    case 0: // active
      WebServer_SetActive( value );
      break;
    case 1: // listenport
      if(value != WebServer_GetListenPort())
      {
        WebServer_SetListenPort( value );
        WebServer->changeListenPort = true;
      }
      break;     
  }
  return CONTROLLER_OK;
}

// Get the property
int WebServerOsc_PropertyGet( int property )
{
  int value = 0;
  switch ( property )
  {
    case 0: // active
      value = WebServer_GetActive( );
      break;
    case 1: // listenport
      value = WebServer_GetListenPort( );
      break;   
  }
  return value;
}

#endif // OSC

#endif // MAKE_CTRL_NETWORK

---

The Make Controller Kit is an open source project maintained by MakingThings.
MakingThings code is released under the Apache 2.0 license.
Bug tracker, development wiki and status can be found at http://dev.makingthings.com.
This document was last updated on 18 May 2009.