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/*
* lws-minimal-ws-client-ping
*
* Copyright (C) 2018 Andy Green <andy@warmcat.com>
*
* This file is made available under the Creative Commons CC0 1.0
* Universal Public Domain Dedication.
*
* This demonstrates a ws client that sends pings from time to time and
* shows when it receives the PONG
*/
#include <libwebsockets.h>
#include <string.h>
#include <signal.h>
#include <pthread.h>
static struct lws_context *context;
static struct lws *client_wsi;
static int interrupted, zero_length_ping, port = 443,
ssl_connection = LCCSCF_USE_SSL;
static const char *server_address = "libwebsockets.org", *pro = "lws-ping-test";
struct pss {
int send_a_ping;
};
static int
connect_client(void)
{
struct lws_client_connect_info i;
memset(&i, 0, sizeof(i));
i.context = context;
i.port = port;
i.address = server_address;
i.path = "/";
i.host = i.address;
i.origin = i.address;
i.ssl_connection = ssl_connection;
i.protocol = pro;
i.local_protocol_name = pro;
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i.pwsi = &client_wsi;
return !lws_client_connect_via_info(&i);
}
static int
callback_minimal_broker(struct lws *wsi, enum lws_callback_reasons reason,
void *user, void *in, size_t len)
{
struct pss *pss = (struct pss *)user;
int n;
switch (reason) {
case LWS_CALLBACK_PROTOCOL_INIT:
goto try;
case LWS_CALLBACK_CLIENT_CONNECTION_ERROR:
lwsl_err("CLIENT_CONNECTION_ERROR: %s\n",
in ? (char *)in : "(null)");
client_wsi = NULL;
lws_timed_callback_vh_protocol(lws_get_vhost(wsi),
lws_get_protocol(wsi), LWS_CALLBACK_USER, 1);
break;
/* --- client callbacks --- */
case LWS_CALLBACK_CLIENT_ESTABLISHED:
lwsl_user("%s: established\n", __func__);
lws_set_timer_usecs(wsi, 5 * LWS_USEC_PER_SEC);
break;
case LWS_CALLBACK_CLIENT_WRITEABLE:
if (pss->send_a_ping) {
uint8_t ping[LWS_PRE + 125];
int m;
pss->send_a_ping = 0;
n = 0;
if (!zero_length_ping)
n = lws_snprintf((char *)ping + LWS_PRE, 125,
"ping body!");
lwsl_user("Sending PING %d...\n", n);
m = lws_write(wsi, ping + LWS_PRE, n, LWS_WRITE_PING);
if (m < n) {
lwsl_err("sending ping failed: %d\n", m);
return -1;
}
lws_callback_on_writable(wsi);
}
break;
case LWS_CALLBACK_WS_CLIENT_DROP_PROTOCOL:
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client_wsi = NULL;
lws_timed_callback_vh_protocol(lws_get_vhost(wsi),
lws_get_protocol(wsi),
LWS_CALLBACK_USER, 1);
break;
case LWS_CALLBACK_CLIENT_RECEIVE_PONG:
lwsl_user("LWS_CALLBACK_CLIENT_RECEIVE_PONG\n");
lwsl_hexdump_notice(in, len);
break;
case LWS_CALLBACK_TIMER:
/* we want to send a ws PING every few seconds */
pss->send_a_ping = 1;
lws_callback_on_writable(wsi);
lws_set_timer_usecs(wsi, 5 * LWS_USEC_PER_SEC);
break;
/* rate-limited client connect retries */
case LWS_CALLBACK_USER:
lwsl_notice("%s: LWS_CALLBACK_USER\n", __func__);
try:
if (connect_client())
lws_timed_callback_vh_protocol(lws_get_vhost(wsi),
lws_get_protocol(wsi),
LWS_CALLBACK_USER, 1);
break;
default:
break;
}
return lws_callback_http_dummy(wsi, reason, user, in, len);
}
static const struct lws_protocols protocols[] = {
{
"lws-ping-test",
callback_minimal_broker,
sizeof(struct pss),
0,
},
{ NULL, NULL, 0, 0 }
};
static void
sigint_handler(int sig)
{
interrupted = 1;
}
int main(int argc, const char **argv)
{
struct lws_context_creation_info info;
const char *p;
int n = 0, logs = LLL_USER | LLL_ERR | LLL_WARN | LLL_NOTICE
/* for LLL_ verbosity above NOTICE to be built into lws,
* lws must have been configured and built with
* -DCMAKE_BUILD_TYPE=DEBUG instead of =RELEASE */
/* | LLL_INFO */ /* | LLL_PARSER */ /* | LLL_HEADER */
/* | LLL_EXT */ /* | LLL_CLIENT */ /* | LLL_LATENCY */
/* | LLL_DEBUG */;
signal(SIGINT, sigint_handler);
if ((p = lws_cmdline_option(argc, argv, "-d")))
logs = atoi(p);
lws_set_log_level(logs, NULL);
lwsl_user("LWS minimal ws client PING\n");
memset(&info, 0, sizeof info); /* otherwise uninitialized garbage */
info.options = LWS_SERVER_OPTION_DO_SSL_GLOBAL_INIT;
info.port = CONTEXT_PORT_NO_LISTEN; /* we do not run any server */
info.protocols = protocols;
#if defined(LWS_WITH_MBEDTLS)
/*
* OpenSSL uses the system trust store. mbedTLS has to be told which
* CA to trust explicitly.
*/
info.client_ssl_ca_filepath = "./libwebsockets.org.cer";
#endif
if (lws_cmdline_option(argc, argv, "-z"))
zero_length_ping = 1;
if ((p = lws_cmdline_option(argc, argv, "--server"))) {
server_address = p;
pro = "lws-minimal";
ssl_connection |= LCCSCF_ALLOW_SELFSIGNED;
}
if ((p = lws_cmdline_option(argc, argv, "--port")))
port = atoi(p);
context = lws_create_context(&info);
if (!context) {
lwsl_err("lws init failed\n");
return 1;
}
while (n >= 0 && !interrupted)
n = lws_service(context, 1000);
lws_context_destroy(context);
lwsl_user("Completed\n");
return 0;
}