hello-world.c

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 /*
  * 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(&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(&p);
 
   PSOCK_SEND_STR(&p, "Hello. What is your name?\n");
   PSOCK_READTO(&p, '\n');
   strncpy(s->name, s->inputbuffer, sizeof(s->name));
   PSOCK_SEND_STR(&p, "Hello ");
   PSOCK_SEND_STR(&p, s->name);
   PSOCK_CLOSE(&p);
   
   PSOCK_END(&p);
 }
 /*---------------------------------------------------------------------------*/