/* ping - ping/pong demo of GRAS features */
-/* Copyright (c) 2003, 2004 Martin Quinson. All rights reserved. */
+/* Copyright (c) 2003, 2004, 2005 Martin Quinson. All rights reserved. */
/* This program is free software; you can redistribute it and/or modify it
* under the terms of the license (GNU LGPL) which comes with this package. */
-#include <stdio.h>
-#include <stdlib.h>
-#include <signal.h>
-
#include "gras.h"
XBT_LOG_NEW_DEFAULT_CATEGORY(Ping,"Messages specific to this example");
-/* **********************************************************************
- * Comon code
- * **********************************************************************/
-
-typedef struct {
- int dummy;
-} msg_ping_t;
-
-/* Function prototypes */
-void register_messages(void);
-
-/* Code */
-void register_messages(void) {
-
+/* register messages which may be sent (common to client and server) */
+static void register_messages(void) {
gras_msgtype_declare("ping", gras_datadesc_by_name("int"));
gras_msgtype_declare("pong", gras_datadesc_by_name("int"));
}
+/* Function prototypes */
+int server (int argc,char *argv[]);
+int client (int argc,char *argv[]);
+
/* **********************************************************************
* Server code
* **********************************************************************/
int endcondition;
} server_data_t;
-/* Function prototypes */
-int server_cb_ping_handler(gras_socket_t expeditor,
- void *payload_data);
-int server (int argc,char *argv[]);
-
-int server_cb_ping_handler(gras_socket_t expeditor,
- void *payload_data) {
+static int server_cb_ping_handler(gras_socket_t expeditor,
+ void *payload_data) {
xbt_error_t errcode;
+ /* 1. Get the payload into the msg variable */
int msg=*(int*)payload_data;
- gras_msgtype_t *pong_t=NULL;
- server_data_t *g=(server_data_t*)gras_userdata_get();
+ /* 2. Retrieve the server's state (globals) */
- g->endcondition = 0;
+ server_data_t *globals=(server_data_t*)gras_userdata_get();
+ globals->endcondition = 0;
+
+ /* 3. Log which client connected */
INFO3("SERVER: >>>>>>>> Got message PING(%d) from %s:%d <<<<<<<<",
msg,
- gras_socket_peer_name(expeditor),
- gras_socket_peer_port(expeditor));
+ gras_socket_peer_name(expeditor), gras_socket_peer_port(expeditor));
+ /* 4. Change the value of the msg variable */
msg = 4321;
+ /* 5. Send it back as payload of a pong message to the expeditor */
errcode = gras_msg_send(expeditor, gras_msgtype_by_name("pong"), &msg);
+ /* 6. Deal with errors */
if (errcode != no_error) {
ERROR1("SERVER: Unable answer with PONG: %s\n", xbt_error_name(errcode));
- gras_socket_close(g->sock);
+ gras_socket_close(globals->sock);
return 1;
}
INFO0("SERVER: >>>>>>>> Answed with PONG(4321) <<<<<<<<");
- g->endcondition = 1;
+
+ /* 7. Set the endcondition boolean to true (and make sure the server stops after receiving it). */
+ globals->endcondition = 1;
+
+ /* 8. Make sure we don't leak sockets */
gras_socket_close(expeditor);
+
+ /* 9. Tell GRAS that we consummed this message */
return 1;
-}
+} /* end_of_server_cb_ping_handler */
int server (int argc,char *argv[]) {
xbt_error_t errcode;
- server_data_t *g;
- gras_msgtype_t *ping_msg=NULL;
+ server_data_t *globals;
int port = 4000;
+ /* 1. Init the GRAS infrastructure and declare my globals */
gras_init(&argc,argv, NULL);
- g=gras_userdata_new(server_data_t);
+ globals=gras_userdata_new(server_data_t);
+ /* 2. Get the port I should listen on from the command line, if specified */
if (argc == 2) {
port=atoi(argv[1]);
}
INFO1("Launch server (port=%d)", port);
- if ((errcode=gras_socket_server(port,&(g->sock)))) {
+ /* 3. Create my master socket */
+ if ((errcode=gras_socket_server(port,&(globals->sock)))) {
CRITICAL1("Error %s encountered while opening the server socket",
xbt_error_name(errcode));
return 1;
}
+ /* 4. Register the known messages. This function is called twice here, but it's because
+ this file also acts as regression test, no need to do so yourself of course. */
register_messages();
- register_messages();
+ register_messages(); /* just to make sure it works ;) */
+
+ /* 5. Register my callback */
gras_cb_register(gras_msgtype_by_name("ping"),&server_cb_ping_handler);
- INFO1("SERVER: >>>>>>>> Listening on port %d <<<<<<<<",
- gras_socket_my_port(g->sock));
- g->endcondition=0;
+ INFO1("SERVER: >>>>>>>> Listening on port %d <<<<<<<<", gras_socket_my_port(globals->sock));
+ globals->endcondition=0;
+ /* 6. Wait up to 10 minutes for an incomming message to handle */
errcode = gras_msg_handle(600.0);
+
+ /* 7. Housekeeping */
if (errcode != no_error)
return errcode;
- if (g->endcondition)
+ if (!globals->endcondition)
+ WARN0("An error occured, the endcondition was not set by the callback");
+ /* 8. Sleep one second, but only in real life, not in simulation */
if (!gras_if_RL())
- gras_os_sleep(1,0);
+ gras_os_sleep(1, 0);
- gras_socket_close(g->sock);
- free(g);
+ /* 9. Free the allocated resources, and shut GRAS down */
+ gras_socket_close(globals->sock);
+ free(globals);
gras_exit();
+
INFO0("SERVER: Done.");
return no_error;
-}
+} /* end_of_server */
/* **********************************************************************
* Client code
* **********************************************************************/
-/* Global private data */
-typedef struct {
- gras_socket_t sock;
-} client_data_t;
-
/* Function prototypes */
-int client (int argc,char *argv[]);
int client(int argc,char *argv[]) {
- xbt_error_t errcode;
- client_data_t *g;
+ xbt_error_t errcode;
+ gras_socket_t toserver; /* peer */
gras_socket_t from;
int ping, pong;
const char *host = "127.0.0.1";
int port = 4000;
+ /* 1. Init the GRAS's infrastructure */
gras_init(&argc, argv, NULL);
- g=gras_userdata_new(client_data_t);
+ /* 2. Get the server's address from the command line, if specified */
if (argc == 3) {
host=argv[1];
port=atoi(argv[2]);
}
INFO2("Launch client (server on %s:%d)",host,port);
- gras_os_sleep(1,0); /* Wait for the server startup */
- if ((errcode=gras_socket_client(host,port,&(g->sock)))) {
+
+ /* 3. Wait for the server startup */
+ gras_os_sleep(1,0);
+
+ /* 4. Create a socket to speak to the server */
+ if ((errcode=gras_socket_client(host,port,&toserver))) {
ERROR1("Client: Unable to connect to the server. Got %s",
xbt_error_name(errcode));
return 1;
INFO2("Client: Connected to %s:%d.",host,port);
+ /* 5. Register the messages.
+ See, it doesn't have to be done completely at the beginning, only before use */
register_messages();
+ /* 6. Keep the user informed of what's going on */
INFO2("Client: >>>>>>>> Connected to server which is on %s:%d <<<<<<<<",
- gras_socket_peer_name(g->sock),gras_socket_peer_port(g->sock));
+ gras_socket_peer_name(toserver),gras_socket_peer_port(toserver));
+ /* 7. Prepare and send the ping message to the server */
ping = 1234;
- errcode = gras_msg_send(g->sock, gras_msgtype_by_name("ping"), &ping);
+ errcode = gras_msg_send(toserver, gras_msgtype_by_name("ping"), &ping);
if (errcode != no_error) {
fprintf(stderr, "Client: Unable send PING to server (%s)\n",
xbt_error_name(errcode));
- gras_socket_close(g->sock);
+ gras_socket_close(toserver);
return 1;
}
INFO3("Client: >>>>>>>> Message PING(%d) sent to %s:%d <<<<<<<<",
ping,
- gras_socket_peer_name(g->sock),gras_socket_peer_port(g->sock));
+ gras_socket_peer_name(toserver),gras_socket_peer_port(toserver));
+ /* 8. Wait for the answer from the server, and deal with issues */
if ((errcode=gras_msg_wait(6000,gras_msgtype_by_name("pong"),
&from,&pong))) {
ERROR1("Client: Why can't I get my PONG message like everyone else (%s)?",
xbt_error_name(errcode));
- gras_socket_close(g->sock);
+ gras_socket_close(toserver);
return 1;
}
+ /* 9. Keep the user informed of what's going on, again */
INFO3("Client: >>>>>>>> Got PONG(%d) got from %s:%d <<<<<<<<",
pong,
gras_socket_peer_name(from),gras_socket_peer_port(from));
- gras_socket_close(g->sock);
- free(g);
+ /* 10. Free the allocated resources, and shut GRAS down */
+ gras_socket_close(toserver);
gras_exit();
INFO0("Client: Done.");
return 0;
-}
+} /* end_of_client */
