Projects/Webserver/Lib/WebserverApp.c

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2010.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6       www.fourwalledcubicle.com
   7 */
   8
   9 /*
  10   Copyright 2010  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, distribute, and sell this
  13   software and its documentation for any purpose is hereby granted
  14   without fee, provided that the above copyright notice appear in
  15   all copies and that both that the copyright notice and this
  16   permission notice and warranty disclaimer appear in supporting
  17   documentation, and that the name of the author not be used in
  18   advertising or publicity pertaining to distribution of the
  19   software without specific, written prior permission.
  20
  21   The author disclaim all warranties with regard to this
  22   software, including all implied warranties of merchantability
  23   and fitness.  In no event shall the author be liable for any
  24   special, indirect or consequential damages or any damages
  25   whatsoever resulting from loss of use, data or profits, whether
  26   in an action of contract, negligence or other tortious action,
  27   arising out of or in connection with the use or performance of
  28   this software.
  29 */
  30
  31 /** \file
  32  *
  33  *  Simple HTTP Webserver Application. When connected to the uIP stack,
  34  *  this will serve out files to HTTP clients.
  35  */
  36
  37 #include "WebserverApp.h"
  38
  39 /** HTTP server response header, for transmission before the page contents. This indicates to the host that a page exists at the
  40  *  given location, and gives extra connection information.
  41  */
  42 char PROGMEM HTTP200Header[] = "HTTP/1.1 200 OK\r\n"
  43                                "Server: LUFA RNDIS\r\n"
  44                                "Content-type: text/html\r\n"
  45                                "Connection: close\r\n\r\n";
  46
  47 /** HTTP server response header, for transmission before a resource not found error. This indicates to the host that the given
  48  *  given URL is invalid, and gives extra error information.
  49  */
  50 char PROGMEM HTTP404Header[] = "HTTP/1.1 404 Not Found\r\n"
  51                                "Server: LUFA RNDIS\r\n"
  52                                "Connection: close\r\n\r\n";
  53
  54 /** HTTP page to serve to the host when a HTTP request is made. This page is too long for a single response, thus it is automatically
  55  *  broken up into smaller blocks and sent as a series of packets each time the webserver application callback is run.
  56  */
  57 char PROGMEM HTTPPage[]   =
  58                 "<html>"
  59                 "       <head>"
  60                 "               <title>"
  61                 "                       LUFA Webserver Demo"
  62                 "               </title>"
  63                 "       </head>"
  64                 "       <body>"
  65                 "               <h1>Hello from your USB AVR!</h1>"
  66                 "               <p>"
  67                 "                       Hello! Welcome to the LUFA RNDIS Demo Webserver test page, running on your USB AVR via the LUFA library and uIP TCP/IP network stack. This"
  68                 "           demonstrates a simple HTTP webserver serving out pages to HTTP clients."
  69                 "                       <br /><br />"
  70                 "                       <small>Project Information: <a href=\"http://www.fourwalledcubicle.com/LUFA.php\">http://www.fourwalledcubicle.com/LUFA.php</a>.</small>"
  71                 "                       <hr />"
  72                 "                       <i>LUFA Version: </i>" LUFA_VERSION_STRING
  73                 "               </p>"
  74                 "       </body>"
  75                 "</html>";
  76
  77 /** Initialization function for the simple HTTP webserver. */
  78 void WebserverApp_Init(void)
  79 {
  80         /* Listen on port 80 for HTTP connections from hosts */
  81         uip_listen(HTONS(80));
  82 }
  83
  84 /** uIP stack application callback for the simple HTTP webserver. This function must be called each time the
  85  *  TCP/IP stack needs a TCP packet to be processed.
  86  */
  87 void WebserverApp_Callback(void)
  88 {
  89         char*    AppDataPtr  = (char*)uip_appdata;
  90         uint16_t AppDataSize = 0;
  91
  92         if (uip_closed() || uip_aborted() || uip_timedout())
  93         {
  94                 /* Terminated or completed connection - don't send any new data */
  95                 return;
  96         }
  97         else if (uip_connected())
  98         {
  99                 /* New connection - initialize connection state and data pointer to the appropriate HTTP header */
 100                 uip_conn->appstate.SendPos      = HTTP200Header;
 101                 uip_conn->appstate.CurrentState = WEBSERVER_STATE_SendHeaders;
 102         }
 103
 104         /* Calculate the maximum segment size and remaining data size */
 105         uint16_t BytesRemaining = strlen_P(uip_conn->appstate.SendPos);
 106         uint16_t MaxSegSize     = uip_mss();
 107
 108         /* No more bytes remaining in the current data being sent - progress to next data chunk or
 109          * terminate the connection once all chunks are sent */
 110         if (!(BytesRemaining))
 111         {
 112                 /* Check which data chunk we are currently sending (header or data) */
 113                 if (uip_conn->appstate.CurrentState == WEBSERVER_STATE_SendHeaders)
 114                 {
 115                         uip_conn->appstate.SendPos = HTTPPage;
 116                         uip_conn->appstate.CurrentState = WEBSERVER_STATE_SendData;
 117                 }
 118                 else if (uip_conn->appstate.CurrentState == WEBSERVER_STATE_SendData)
 119                 {
 120                         uip_close();
 121                         uip_conn->appstate.CurrentState = WEBSERVER_STATE_Closed;
 122                 }
 123
 124                 return;
 125         }
 126         else if (BytesRemaining > MaxSegSize)
 127         {
 128                 /* More bytes remaining to send than the maximum segment size, send next chunk */
 129                 AppDataSize = MaxSegSize;
 130         }
 131         else
 132         {
 133                 /* Less bytes than the segment size remaining, send all remaining bytes in the one packet */
 134                 AppDataSize = BytesRemaining;
 135         }
 136
 137         /* Copy over the next data segment to the application buffer, advance send position pointer */
 138         strncpy_P(uip_appdata, uip_conn->appstate.SendPos, AppDataSize);
 139         uip_conn->appstate.SendPos += AppDataSize;
 140
 141         /* Send the data to the requesting host */
 142         uip_send(AppDataPtr, AppDataSize);
 143 }