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/**
* \addtogroup helloworld
* @{
*/
/**
* \file
* An example of how to write uIP applications
* with protosockets.
* \author
* Adam Dunkels <adam@sics.se>
*/
/*
* This is a short example of how to write uIP applications using
* protosockets.
*/
/*
* We define the application state (struct hello_world_state) in the
* hello-world.h file, so we need to include it here. We also include
* uip.h (since this cannot be included in hello-world.h) and
* <string.h>, since we use the memcpy() function in the code.
*/
#include "hello-world.h"
#include "uip.h"
#include <string.h>
/*
* Declaration of the protosocket function that handles the connection
* (defined at the end of the code).
*/
static int handle_connection(struct hello_world_state *s);
/*---------------------------------------------------------------------------*/
/*
* The initialization function. We must explicitly call this function
* from the system initialization code, some time after uip_init() is
* called.
*/
void
hello_world_init(void)
{
/* We start to listen for connections on TCP port 1000. */
uip_listen(HTONS(1000));
}
/*---------------------------------------------------------------------------*/
/*
* In hello-world.h we have defined the UIP_APPCALL macro to
* hello_world_appcall so that this funcion is uIP's application
* function. This function is called whenever an uIP event occurs
* (e.g. when a new connection is established, new data arrives, sent
* data is acknowledged, data needs to be retransmitted, etc.).
*/
void
hello_world_appcall(void)
{
/*
* The uip_conn structure has a field called "appstate" that holds
* the application state of the connection. We make a pointer to
* this to access it easier.
*/
struct hello_world_state *s = &(uip_conn->appstate);
/*
* If a new connection was just established, we should initialize
* the protosocket in our applications' state structure.
*/
if(uip_connected()) {
PSOCK_INIT(&s->p, s->inputbuffer, sizeof(s->inputbuffer));
}
/*
* Finally, we run the protosocket function that actually handles
* the communication. We pass it a pointer to the application state
* of the current connection.
*/
handle_connection(s);
}
/*---------------------------------------------------------------------------*/
/*
* This is the protosocket function that handles the communication. A
* protosocket function must always return an int, but must never
* explicitly return - all return statements are hidden in the PSOCK
* macros.
*/
static int
handle_connection(struct hello_world_state *s)
{
PSOCK_BEGIN(&s->p);
PSOCK_SEND_STR(&s->p, "Hello. What is your name?\n");
PSOCK_READTO(&s->p, '\n');
strncpy(s->name, s->inputbuffer, sizeof(s->name));
PSOCK_SEND_STR(&s->p, "Hello ");
PSOCK_SEND_STR(&s->p, s->name);
PSOCK_CLOSE(&s->p);
PSOCK_END(&s->p);
}
/*---------------------------------------------------------------------------*/
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