Simple HTTP Server
Provide the code to use the Ethernet MAC Layer as an HTTP Server. In the current state it uses the lwip stack to build a full functional TCP/IP stack. This http Server is a very simple one. It is build by callback routines and can serve one package requests only. But it is simple to extend.
Library
Import Library:
http://mbed.org/projects/cookbook/svn/EMAC/lwip/trunk
or import precompiled Library:
http://mbed.org/projects/cookbook/svn/EMAC/lwip/precomp
Import Example program:
http://mbed.org/projects/cookbook/svn/EMAC/lwip/examples/simplehttpd
- For details on how to use this in the compiler, see Importing Projects and Libraries in to the Compiler
Simple HTTPd
#include "TCPCallbackConnection.h"
#include "NetServer.h"
#include "mbed.h"
/* Some Lights */
DigitalOut led1(LED1);
DigitalOut led2(LED2);
int x = 0;
/* Two static html pages ready for serving, includeing http header */
const char *page[] = {
"HTTP/1.1 200 OK\r\n"
"Server:mbed embedded\r\n"
"Content-Type: text/html\r\n"
"Content-Length: 190\r\n"
"\r\n"
"<html>\r\n"
" <header>\r\n"
" <title>Whats up?<title>\r\n"
" </header>\r\n"
" <body>\r\n"
" <h1>Hello World!!11elf</h1>\r\n"
" <p>Have a greate day.</p>\r\n"
" <a href=\"/1.html\">turn </a>\r\n"
" </body>\r\n"
"</html>\r\n"
"\r\n"
,
"HTTP/1.1 200 OK\r\n"
"Server:mbed embedded\r\n"
"Content-Type: text/html\r\n"
"Content-Length: 178\r\n"
"\r\n"
"<html>\r\n"
" <header>\r\n"
" <title>LED Power<title>\r\n"
" </header>\r\n"
" <body>\r\n"
" <h1>Lets rotate!!11elf</h1>\r\n"
" <p>Bam!!!!!!!!!!.</p>\r\n"
" <a href=\"/\">back</a>\r\n"
" </body>\r\n"
"</html>\r\n"
"\r\n"
};
/* Every time called if a packet is received for a */
/* TCPConnection which registerd this Callback. */
err_t recv_callback(TCPCallbackConnection *arg, struct pbuf *p, err_t err) {
int i;
char *data;
/* Check if status is ok and data is arrived. */
if (err == ERR_OK && p != NULL) {
/* Inform TCP that we have taken the data. */
arg->recved(p->tot_len);
data = static_cast<char *>(p->payload);
/* If the data is a GET request we can handle it. */
if (strncmp(data, "GET ", 4) == 0) {
for (i = 0; i < 40; i++) {
if (((char *)data + 4)[i] == ' ' ||
((char *)data + 4)[i] == '\r' ||
((char *)data + 4)[i] == '\n') {
((char *)data + 4)[i] = 0;
}
}
/* Check the URL */
/* We only know two URLs /1.html and default */
/* store the URL information in our global x variable to change twinkle behaviour. */
x = (strncmp((char *)(data + 4), "/1.html", 7) == 0)? 1: 0;
/* Clean up the Memory */
/* Send the right page as answere. */
if (arg->write((void *)page[x], strlen(page[x])) != ERR_OK) {
error("Could not write", 0);
}
} else {
/* This message was not a GET request.
Maybe it was a follow message or another kind of request. */
}
} else {
/* No data arrived */
/* That means the client closes the connection and sent us a packet with FIN flag set to 1. */
/* We have to cleanup and destroy out TCPConnection. */
arg->close();
NetServer::get()->free(arg);
}
pbuf_free(p);
/* Don't panic! Everything is fine. */
return ERR_OK;
}
/* Accept an incomming call on the registered port */
err_t accept_callback(TCPCallbackListener *arg, struct tcp_pcb *npcb, err_t err) {
/* Create a new TCPConnection for the new incomming call. */
TCPCallbackConnection *con = new TCPCallbackConnection((TCPListener *)arg, npcb,
NO_SENT_FNC,
&recv_callback, /* set only a callback for receiving data. */
NO_POLL_FNC,
NO_CONNECT_FNC,
NO_ERR_FNC
);
/* Don't panic! Everything is fine. */
return ERR_OK;
}
int main(void) {
/* Bind a function to a tcp port */
NetServer::ready()->bindTCPPort(80, &accept_callback);
/* Give the signal that we are ready */
printf("entering while loop\n");
while (1) {
wait(0.1);
NetServer::poll();
if (x) {
led1 = !led1;
} else {
led2 = !led2;
}
}
}
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| Source Code of simplehttpd.bin (LPC1768 LPC2368) |