uIP 1.0: apps/hello-world/hello-world.c Source File

00001 /**
+00002  * \addtogroup helloworld
+00003  * @{
+00004  */
+00005 
+00006 /**
+00007  * \file
+00008  *         An example of how to write uIP applications
+00009  *         with protosockets.
+00010  * \author
+00011  *         Adam Dunkels <adam@sics.se>
+00012  */
+00013 
+00014 /*
+00015  * This is a short example of how to write uIP applications using
+00016  * protosockets.
+00017  */
+00018 
+00019 /*
+00020  * We define the application state (struct hello_world_state) in the
+00021  * hello-world.h file, so we need to include it here. We also include
+00022  * uip.h (since this cannot be included in hello-world.h) and
+00023  * <string.h>, since we use the memcpy() function in the code.
+00024  */
+00025 #include "hello-world.h"
+00026 #include "uip.h"
+00027 #include <string.h>
+00028 
+00029 /*
+00030  * Declaration of the protosocket function that handles the connection
+00031  * (defined at the end of the code).
+00032  */
+00033 static int handle_connection(struct hello_world_state *s);
+00034 /*---------------------------------------------------------------------------*/
+00035 /*
+00036  * The initialization function. We must explicitly call this function
+00037  * from the system initialization code, some time after uip_init() is
+00038  * called.
+00039  */
+00040 void
+00041 hello_world_init(void)
+00042 {
+00043   /* We start to listen for connections on TCP port 1000. */
+00044   uip_listen(HTONS(1000));
+00045 }
+00046 /*---------------------------------------------------------------------------*/
+00047 /*
+00048  * In hello-world.h we have defined the UIP_APPCALL macro to
+00049  * hello_world_appcall so that this funcion is uIP's application
+00050  * function. This function is called whenever an uIP event occurs
+00051  * (e.g. when a new connection is established, new data arrives, sent
+00052  * data is acknowledged, data needs to be retransmitted, etc.).
+00053  */
+00054 void
+00055 hello_world_appcall(void)
+00056 {
+00057   /*
+00058    * The uip_conn structure has a field called "appstate" that holds
+00059    * the application state of the connection. We make a pointer to
+00060    * this to access it easier.
+00061    */
+00062   struct hello_world_state *s = &(uip_conn->appstate);
+00063 
+00064   /*
+00065    * If a new connection was just established, we should initialize
+00066    * the protosocket in our applications' state structure.
+00067    */
+00068   if(uip_connected()) {
+00069     PSOCK_INIT(&s->p, s->inputbuffer, sizeof(s->inputbuffer));
+00070   }
+00071 
+00072   /*
+00073    * Finally, we run the protosocket function that actually handles
+00074    * the communication. We pass it a pointer to the application state
+00075    * of the current connection.
+00076    */
+00077   handle_connection(s);
+00078 }
+00079 /*---------------------------------------------------------------------------*/
+00080 /*
+00081  * This is the protosocket function that handles the communication. A
+00082  * protosocket function must always return an int, but must never
+00083  * explicitly return - all return statements are hidden in the PSOCK
+00084  * macros.
+00085  */
+00086 static int
+00087 handle_connection(struct hello_world_state *s)
+00088 {
+00089   PSOCK_BEGIN(&s->p);
+00090 
+00091   PSOCK_SEND_STR(&s->p, "Hello. What is your name?\n");
+00092   PSOCK_READTO(&s->p, '\n');
+00093   strncpy(s->name, s->inputbuffer, sizeof(s->name));
+00094   PSOCK_SEND_STR(&s->p, "Hello ");
+00095   PSOCK_SEND_STR(&s->p, s->name);
+00096   PSOCK_CLOSE(&s->p);
+00097   
+00098   PSOCK_END(&s->p);
+00099 }
+00100 /*---------------------------------------------------------------------------*/
+