1 /*
2  * lws-minimal-http-server-form-get
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 a minimal http server that performs a form GET with a couple
10  * of parameters.  It dumps the parameters to the console log and redirects
11  * to another page.
12  */
13 
14 #include <libwebsockets.h>
15 #include <string.h>
16 #include <signal.h>
17 
18 static int interrupted;
19 
20 static const char * param_names[] = {
21 	"text1",
22 	"send"
23 };
24 
25 static int
callback_http(struct lws * wsi,enum lws_callback_reasons reason,void * user,void * in,size_t len)26 callback_http(struct lws *wsi, enum lws_callback_reasons reason, void *user,
27 	      void *in, size_t len)
28 {
29 	uint8_t buf[LWS_PRE + LWS_RECOMMENDED_MIN_HEADER_SPACE],
30 		*start = &buf[LWS_PRE], *p = start,
31 		*end = &buf[sizeof(buf) - 1];
32 	const char *val;
33 	int n;
34 
35 	switch (reason) {
36 	case LWS_CALLBACK_HTTP:
37 
38 		if (!lws_hdr_total_length(wsi, WSI_TOKEN_GET_URI))
39 			/* not a GET */
40 			break;
41 		lwsl_err("%s: %s\n", __func__, (const char *)in);
42 		if (strcmp((const char *)in, "/form1"))
43 			/* not our form URL */
44 			break;
45 
46 		/* we just dump the decoded things to the log */
47 
48 		for (n = 0; n < (int)LWS_ARRAY_SIZE(param_names); n++) {
49 			val = lws_get_urlarg_by_name(wsi, param_names[n],
50 					(char *)buf, sizeof(buf));
51 			if (!val)
52 				lwsl_user("%s: undefined\n", param_names[n]);
53 			else
54 				lwsl_user("%s: (len %d) '%s'\n", param_names[n],
55 					  (int)strlen((const char *)buf),buf);
56 		}
57 
58 		/*
59 		 * Our response is to redirect to a static page.  We could
60 		 * have generated a dynamic html page here instead.
61 		 */
62 
63 		if (lws_http_redirect(wsi, HTTP_STATUS_MOVED_PERMANENTLY,
64 				      (unsigned char *)"after-form1.html",
65 				      16, &p, end) < 0)
66 			return -1;
67 		break;
68 
69 	default:
70 		break;
71 	}
72 
73 	return lws_callback_http_dummy(wsi, reason, user, in, len);
74 }
75 
76 static struct lws_protocols protocols[] = {
77 	{ "http", callback_http, 0, 0 },
78 	{ NULL, NULL, 0, 0 } /* terminator */
79 };
80 
81 /* default mount serves the URL space from ./mount-origin */
82 
83 static const struct lws_http_mount mount = {
84 	/* .mount_next */	       NULL,		/* linked-list "next" */
85 	/* .mountpoint */		"/",		/* mountpoint URL */
86 	/* .origin */		"./mount-origin",	/* serve from dir */
87 	/* .def */			"index.html",	/* default filename */
88 	/* .protocol */			NULL,
89 	/* .cgienv */			NULL,
90 	/* .extra_mimetypes */		NULL,
91 	/* .interpret */		NULL,
92 	/* .cgi_timeout */		0,
93 	/* .cache_max_age */		0,
94 	/* .auth_mask */		0,
95 	/* .cache_reusable */		0,
96 	/* .cache_revalidate */		0,
97 	/* .cache_intermediaries */	0,
98 	/* .origin_protocol */		LWSMPRO_FILE,	/* files in a dir */
99 	/* .mountpoint_len */		1,		/* char count */
100 	/* .basic_auth_login_file */	NULL,
101 };
102 
sigint_handler(int sig)103 void sigint_handler(int sig)
104 {
105 	interrupted = 1;
106 }
107 
main(int argc,const char ** argv)108 int main(int argc, const char **argv)
109 {
110 	struct lws_context_creation_info info;
111 	struct lws_context *context;
112 	const char *p;
113 	int n = 0, logs = LLL_USER | LLL_ERR | LLL_WARN | LLL_NOTICE
114 			/* for LLL_ verbosity above NOTICE to be built into lws,
115 			 * lws must have been configured and built with
116 			 * -DCMAKE_BUILD_TYPE=DEBUG instead of =RELEASE */
117 			/* | LLL_INFO */ /* | LLL_PARSER */ /* | LLL_HEADER */
118 			/* | LLL_EXT */ /* | LLL_CLIENT */ /* | LLL_LATENCY */
119 			/* | LLL_DEBUG */;
120 
121 	signal(SIGINT, sigint_handler);
122 
123 	if ((p = lws_cmdline_option(argc, argv, "-d")))
124 		logs = atoi(p);
125 
126 	lws_set_log_level(logs, NULL);
127 	lwsl_user("LWS minimal http server GET | visit http://localhost:7681\n");
128 
129 	memset(&info, 0, sizeof info); /* otherwise uninitialized garbage */
130 	info.port = 7681;
131 	info.protocols = protocols;
132 	info.mounts = &mount;
133 	info.options =
134 		LWS_SERVER_OPTION_HTTP_HEADERS_SECURITY_BEST_PRACTICES_ENFORCE;
135 
136 	context = lws_create_context(&info);
137 	if (!context) {
138 		lwsl_err("lws init failed\n");
139 		return 1;
140 	}
141 
142 	while (n >= 0 && !interrupted)
143 		n = lws_service(context, 0);
144 
145 	lws_context_destroy(context);
146 
147 	return 0;
148 }
149