1 /*
2 * lws-minimal-ws-client
3 *
4 * Written in 2010-2019 by Andy Green <andy@warmcat.com>
5 *
6 * This file is made available under the Creative Commons CC0 1.0
7 * Universal Public Domain Dedication.
8 *
9 * This demonstrates the a minimal ws client using lws.
10 *
11 * It connects to https://libwebsockets.org/ and makes a
12 * wss connection to the dumb-increment protocol there. While
13 * connected, it prints the numbers it is being sent by
14 * dumb-increment protocol.
15 */
16
17 #include <libwebsockets.h>
18 #include <string.h>
19 #include <signal.h>
20
21 static int interrupted, rx_seen, test;
22 static struct lws *client_wsi;
23
24 static int
callback_dumb_increment(struct lws * wsi,enum lws_callback_reasons reason,void * user,void * in,size_t len)25 callback_dumb_increment(struct lws *wsi, enum lws_callback_reasons reason,
26 void *user, void *in, size_t len)
27 {
28 switch (reason) {
29
30 /* because we are protocols[0] ... */
31 case LWS_CALLBACK_CLIENT_CONNECTION_ERROR:
32 lwsl_err("CLIENT_CONNECTION_ERROR: %s\n",
33 in ? (char *)in : "(null)");
34 client_wsi = NULL;
35 break;
36
37 case LWS_CALLBACK_CLIENT_ESTABLISHED:
38 lwsl_user("%s: established\n", __func__);
39 break;
40
41 case LWS_CALLBACK_CLIENT_RECEIVE:
42 lwsl_user("RX: %s\n", (const char *)in);
43 rx_seen++;
44 if (test && rx_seen == 10)
45 interrupted = 1;
46 break;
47
48 case LWS_CALLBACK_CLIENT_CLOSED:
49 client_wsi = NULL;
50 break;
51
52 default:
53 break;
54 }
55
56 return lws_callback_http_dummy(wsi, reason, user, in, len);
57 }
58
59 static const struct lws_protocols protocols[] = {
60 {
61 "dumb-increment-protocol",
62 callback_dumb_increment,
63 0, 0, 0, NULL, 0
64 },
65 LWS_PROTOCOL_LIST_TERM
66 };
67
68 static void
sigint_handler(int sig)69 sigint_handler(int sig)
70 {
71 interrupted = 1;
72 }
73
main(int argc,const char ** argv)74 int main(int argc, const char **argv)
75 {
76 struct lws_context_creation_info info;
77 struct lws_client_connect_info i;
78 struct lws_context *context;
79 const char *p;
80 int n = 0, logs = LLL_USER | LLL_ERR | LLL_WARN | LLL_NOTICE
81 /* for LLL_ verbosity above NOTICE to be built into lws, lws
82 * must have been configured with -DCMAKE_BUILD_TYPE=DEBUG
83 * instead of =RELEASE */
84 /* | LLL_INFO */ /* | LLL_PARSER */ /* | LLL_HEADER */
85 /* | LLL_EXT */ /* | LLL_CLIENT */ /* | LLL_LATENCY */
86 /* | LLL_DEBUG */;
87
88 signal(SIGINT, sigint_handler);
89 if ((p = lws_cmdline_option(argc, argv, "-d")))
90 logs = atoi(p);
91
92 test = !!lws_cmdline_option(argc, argv, "-t");
93
94 lws_set_log_level(logs, NULL);
95 lwsl_user("LWS minimal ws client rx [-d <logs>] [--h2] [-t (test)]\n");
96
97 memset(&info, 0, sizeof info); /* otherwise uninitialized garbage */
98 info.options = LWS_SERVER_OPTION_DO_SSL_GLOBAL_INIT;
99 info.port = CONTEXT_PORT_NO_LISTEN; /* we do not run any server */
100 info.protocols = protocols;
101 info.timeout_secs = 10;
102 info.connect_timeout_secs = 30;
103 #if defined(LWS_WITH_MBEDTLS) || defined(USE_WOLFSSL)
104 /*
105 * OpenSSL uses the system trust store. mbedTLS has to be told which
106 * CA to trust explicitly.
107 */
108 info.client_ssl_ca_filepath = "./libwebsockets.org.cer";
109 #endif
110
111 /*
112 * since we know this lws context is only ever going to be used with
113 * one client wsis / fds / sockets at a time, let lws know it doesn't
114 * have to use the default allocations for fd tables up to ulimit -n.
115 * It will just allocate for 1 internal and 1 (+ 1 http2 nwsi) that we
116 * will use.
117 */
118 info.fd_limit_per_thread = 1 + 1 + 1;
119
120 context = lws_create_context(&info);
121 if (!context) {
122 lwsl_err("lws init failed\n");
123 return 1;
124 }
125
126 memset(&i, 0, sizeof i); /* otherwise uninitialized garbage */
127 i.context = context;
128 i.port = 443;
129 i.address = "libwebsockets.org";
130 i.path = "/";
131 i.host = i.address;
132 i.origin = i.address;
133 i.ssl_connection = LCCSCF_USE_SSL;
134 i.protocol = protocols[0].name; /* "dumb-increment-protocol" */
135 i.pwsi = &client_wsi;
136
137 if (lws_cmdline_option(argc, argv, "--h2"))
138 i.alpn = "h2";
139
140 lws_client_connect_via_info(&i);
141
142 while (n >= 0 && client_wsi && !interrupted)
143 n = lws_service(context, 0);
144
145 lws_context_destroy(context);
146
147 lwsl_user("Completed %s\n", rx_seen > 10 ? "OK" : "Failed");
148
149 return rx_seen > 10;
150 }
151