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/*
* libwebsockets-test-client - libwebsockets test implementation
*
* Copyright (C) 2011 Andy Green <andy@warmcat.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation:
* version 2.1 of the License.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301 USA
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <getopt.h>
#include <string.h>
#include "../lib/libwebsockets.h"
#include <poll.h>
/*
* This demo shows how to connect multiple websockets simultaneously to a
* websocket server (there is no restriction on their having to be the same
* server just it simplifies the demo).
*
* dumb-increment-protocol: we connect to the server and print the number
* we are given
*
* lws-mirror-protocol: draws random circles, which are mirrored on to every
* client (see them being drawn in every browser
* session also using the test server)
*/
enum demo_protocols {
PROTOCOL_DUMB_INCREMENT,
PROTOCOL_LWS_MIRROR,
/* always last */
DEMO_PROTOCOL_COUNT
};
/* dumb_increment protocol */
static int
callback_dumb_increment(struct libwebsocket *wsi,
enum libwebsocket_callback_reasons reason,
void *user, void *in, size_t len)
{
switch (reason) {
case LWS_CALLBACK_CLIENT_RECEIVE:
((char *)in)[len] = '\0';
fprintf(stderr, "rx %d '%s'\n", (int)len, (char *)in);
break;
default:
break;
}
return 0;
}
/* lws-mirror_protocol */
static int
callback_lws_mirror(struct libwebsocket *wsi,
enum libwebsocket_callback_reasons reason,
void *user, void *in, size_t len)
{
unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 4096 +
LWS_SEND_BUFFER_POST_PADDING];
int l;
switch (reason) {
case LWS_CALLBACK_CLIENT_ESTABLISHED:
/*
* start the ball rolling,
* LWS_CALLBACK_CLIENT_WRITEABLE will come next service
*/
libwebsocket_callback_on_writable(wsi);
break;
case LWS_CALLBACK_CLIENT_RECEIVE:
/* fprintf(stderr, "rx %d '%s'\n", (int)len, (char *)in); */
break;
case LWS_CALLBACK_CLIENT_WRITEABLE:
l = sprintf((char *)&buf[LWS_SEND_BUFFER_PRE_PADDING],
"c #%06X %d %d %d;",
(int)random() & 0xffffff,
(int)random() % 500,
(int)random() % 250,
(int)random() % 24);
libwebsocket_write(wsi,
&buf[LWS_SEND_BUFFER_PRE_PADDING], l, LWS_WRITE_TEXT);
/* get notified as soon as we can write again */
libwebsocket_callback_on_writable(wsi);
/*
* without at least this delay, we choke the browser
* and the connection stalls, despite we now take care about
* flow control
*/
usleep(200);
break;
default:
break;
}
return 0;
}
/* list of supported protocols and callbacks */
static struct libwebsocket_protocols protocols[] = {
[PROTOCOL_DUMB_INCREMENT] = {
.name = "dumb-increment-protocol",
.callback = callback_dumb_increment,
},
[PROTOCOL_LWS_MIRROR] = {
.name = "lws-mirror-protocol",
.callback = callback_lws_mirror,
},
[DEMO_PROTOCOL_COUNT] = { /* end of list */
.callback = NULL
}
};
static struct option options[] = {
{ "help", no_argument, NULL, 'h' },
{ "port", required_argument, NULL, 'p' },
{ "ssl", no_argument, NULL, 's' },
{ NULL, 0, 0, 0 }
};
int main(int argc, char **argv)
{
int n = 0;
int port = 7681;
int use_ssl = 0;
struct libwebsocket_context *context;
const char *address = argv[1];
struct libwebsocket *wsi_dumb;
struct libwebsocket *wsi_mirror;
fprintf(stderr, "libwebsockets test client\n"
"(C) Copyright 2010 Andy Green <andy@warmcat.com> "
"licensed under LGPL2.1\n");
if (argc < 2)
goto usage;
optind++;
while (n >= 0) {
n = getopt_long(argc, argv, "hsp:", options, NULL);
if (n < 0)
continue;
switch (n) {
case 's':
use_ssl = 2; /* 2 = allow selfsigned */
break;
case 'p':
port = atoi(optarg);
break;
case 'h':
goto usage;
}
}
/*
* create the websockets context. This tracks open connections and
* knows how to route any traffic and which protocol version to use,
* and if each connection is client or server side.
*
* For this client-only demo, we tell it to not listen on any port.
*/
context = libwebsocket_create_context(CONTEXT_PORT_NO_LISTEN,
protocols, NULL, NULL, -1, -1);
if (context == NULL) {
fprintf(stderr, "Creating libwebsocket context failed\n");
return 1;
}
/* create a client websocket using dumb increment protocol */
wsi_dumb = libwebsocket_client_connect(context, address, port, use_ssl,
"/", libwebsocket_canonical_hostname(context), "origin",
protocols[PROTOCOL_DUMB_INCREMENT].name);
if (wsi_dumb == NULL) {
fprintf(stderr, "libwebsocket dumb connect failed\n");
return -1;
}
/* create a client websocket using mirror protocol */
wsi_mirror = libwebsocket_client_connect(context, address, port,
use_ssl, "/", libwebsocket_canonical_hostname(context), "origin",
protocols[PROTOCOL_LWS_MIRROR].name);
if (wsi_mirror == NULL) {
fprintf(stderr, "libwebsocket dumb connect failed\n");
return -1;
}
fprintf(stderr, "Websocket connections opened\n");
/*
* sit there servicing the websocket context to handle incoming
* packets, and drawing random circles on the mirror protocol websocket
*/
n = 0;
while (n >= 0)
n = libwebsocket_service(context, 1000);
libwebsocket_client_close(wsi_dumb);
libwebsocket_client_close(wsi_mirror);
libwebsocket_context_destroy(context);
return 0;
usage:
fprintf(stderr, "Usage: libwebsockets-test-client "
"<server address> [--port=<p>] "
"[--ssl]\n");
return 1;
}
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