1 /*
2 * lws-minimal-raw-adopt-tcp
3 *
4 * Written in 2010-2019 by Andy Green <[email protected]>
5 *
6 * This file is made available under the Creative Commons CC0 1.0
7 * Universal Public Domain Dedication.
8 *
9 * This demonstrates integrating somebody else's connected tcp
10 * socket into the lws event loop as a RAW wsi. It's interesting in
11 * the kind of situation where you already have a connected socket
12 * in your application, and you need to hand it over to lws to deal with.
13 *
14 * Lws supports "adopting" these foreign sockets.
15 *
16 * If you simply want a connected client raw socket using lws alone, you
17 * can just use lws_client_connect_via_info() with info.method = "RAW".
18 *
19 */
20
21 #include <libwebsockets.h>
22 #include <string.h>
23 #include <signal.h>
24 #if !defined(WIN32)
25 #include <sys/socket.h>
26 #include <netinet/in.h>
27 #include <netdb.h>
28 #include <arpa/inet.h>
29 #endif
30 #include <sys/types.h>
31 #include <stdio.h>
32 #include <string.h>
33 #include <stdlib.h>
34 #if !defined(WIN32)
35 #include <unistd.h>
36 #endif
37 #include <errno.h>
38
39 static int
callback_raw_test(struct lws * wsi,enum lws_callback_reasons reason,void * user,void * in,size_t len)40 callback_raw_test(struct lws *wsi, enum lws_callback_reasons reason,
41 void *user, void *in, size_t len)
42 {
43
44 switch (reason) {
45
46 /* callbacks related to raw socket descriptor */
47
48 case LWS_CALLBACK_RAW_ADOPT:
49 lwsl_user("LWS_CALLBACK_RAW_ADOPT\n");
50 lws_callback_on_writable(wsi);
51 break;
52
53 case LWS_CALLBACK_RAW_CLOSE:
54 lwsl_user("LWS_CALLBACK_RAW_CLOSE\n");
55 break;
56
57 case LWS_CALLBACK_RAW_RX:
58 lwsl_user("LWS_CALLBACK_RAW_RX (%d)\n", (int)len);
59 lwsl_hexdump_level(LLL_NOTICE, in, len);
60 break;
61
62 case LWS_CALLBACK_RAW_WRITEABLE:
63 if (lws_write(wsi,
64 (uint8_t *)"GET / HTTP/1.1\xd\xa\xd\xa", 18,
65 LWS_WRITE_RAW) != 18) {
66 lwsl_notice("%s: raw write failed\n", __func__);
67 return 1;
68 }
69 break;
70
71 default:
72 break;
73 }
74
75 return 0;
76 }
77
78 static struct lws_protocols protocols[] = {
79 { "raw-test", callback_raw_test, 0, 0, 0, NULL, 0 },
80 LWS_PROTOCOL_LIST_TERM
81 };
82
83 static int interrupted;
84
sigint_handler(int sig)85 void sigint_handler(int sig)
86 {
87 interrupted = 1;
88 }
89
main(int argc,const char ** argv)90 int main(int argc, const char **argv)
91 {
92 struct lws_context_creation_info info;
93 struct lws_context *context;
94 lws_sock_file_fd_type sock;
95 struct addrinfo h, *r, *rp;
96 struct lws_vhost *vhost;
97 const char *p;
98 int n = 0, logs = LLL_USER | LLL_ERR | LLL_WARN | LLL_NOTICE
99 /* for LLL_ verbosity above NOTICE to be built into lws,
100 * lws must have been configured and built with
101 * -DCMAKE_BUILD_TYPE=DEBUG instead of =RELEASE */
102 /* | LLL_INFO */ /* | LLL_PARSER */ /* | LLL_HEADER */
103 /* | LLL_EXT */ /* | LLL_CLIENT */ /* | LLL_LATENCY */
104 /* | LLL_DEBUG */;
105
106 signal(SIGINT, sigint_handler);
107
108 if ((p = lws_cmdline_option(argc, argv, "-d")))
109 logs = atoi(p);
110
111 lws_set_log_level(logs, NULL);
112 lwsl_user("LWS minimal raw adopt tcp\n");
113
114 memset(&info, 0, sizeof info); /* otherwise uninitialized garbage */
115 info.options = LWS_SERVER_OPTION_EXPLICIT_VHOSTS;
116
117 context = lws_create_context(&info);
118 if (!context) {
119 lwsl_err("lws init failed\n");
120 return 1;
121 }
122
123 info.port = CONTEXT_PORT_NO_LISTEN_SERVER;
124 info.protocols = protocols;
125
126 vhost = lws_create_vhost(context, &info);
127 if (!vhost) {
128 lwsl_err("lws vhost creation failed\n");
129 goto bail;
130 }
131
132 /*
133 * Connect our own "foreign" socket to libwebsockets.org:80
134 *
135 * Normally you would do this with lws_client_connect_via_info() inside
136 * the lws event loop, hiding all this detail. But this example
137 * demonstrates how to integrate an externally-connected "foreign"
138 * socket, so we create one by hand.
139 */
140
141 memset(&h, 0, sizeof(h));
142 h.ai_family = AF_UNSPEC; /* Allow IPv4 or IPv6 */
143 h.ai_socktype = SOCK_STREAM;
144 h.ai_protocol = IPPROTO_TCP;
145
146 n = getaddrinfo("libwebsockets.org", "80", &h, &r);
147 if (n) {
148 lwsl_err("%s: problem resolving libwebsockets.org: %s\n", __func__, gai_strerror(n));
149 return 1;
150 }
151
152 for (rp = r; rp; rp = rp->ai_next) {
153 sock.sockfd = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
154 if (sock.sockfd != LWS_SOCK_INVALID)
155 break;
156 }
157 if (!rp) {
158 lwsl_err("%s: unable to create INET socket\n", __func__);
159 freeaddrinfo(r);
160
161 return 1;
162 }
163
164 lwsl_user("Starting connect...\n");
165 if (connect(sock.sockfd, rp->ai_addr, sizeof(*rp->ai_addr)) < 0) {
166 lwsl_err("%s: unable to connect to libwebsockets.org:80\n", __func__);
167 freeaddrinfo(r);
168 return 1;
169 }
170
171 freeaddrinfo(r);
172 signal(SIGINT, sigint_handler);
173 lwsl_user("Connected...\n");
174
175 /* our foreign socket is connected... adopt it into lws */
176
177 if (!lws_adopt_descriptor_vhost(vhost, LWS_ADOPT_SOCKET, sock,
178 protocols[0].name, NULL)) {
179 lwsl_err("%s: foreign socket adoption failed\n", __func__);
180 goto bail;
181 }
182
183 while (n >= 0 && !interrupted)
184 n = lws_service(context, 0);
185
186 bail:
187 lws_context_destroy(context);
188
189 return 0;
190 }
191