1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
|
/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* SPDX-License-Identifier: curl
*
***************************************************************************/
/* <DESC>
* WebSocket using CONNECT_ONLY
* </DESC>
*/
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <curl/curl.h>
static int ping(CURL *curl, const char *send_payload)
{
size_t sent;
CURLcode result =
curl_ws_send(curl, send_payload, strlen(send_payload), &sent, 0,
CURLWS_PING);
return (int)result;
}
static int recv_pong(CURL *curl, const char *expected_payload)
{
size_t rlen;
const struct curl_ws_frame *meta;
char buffer[256];
CURLcode result = curl_ws_recv(curl, buffer, sizeof(buffer), &rlen, &meta);
if(!result) {
if(meta->flags & CURLWS_PONG) {
int same = 0;
fprintf(stderr, "ws: got PONG back\n");
if(rlen == strlen(expected_payload)) {
if(!memcmp(expected_payload, buffer, rlen)) {
fprintf(stderr, "ws: got the same payload back\n");
same = 1;
}
}
if(!same)
fprintf(stderr, "ws: did NOT get the same payload back\n");
}
else {
fprintf(stderr, "recv_pong: got %u bytes rflags %x\n", (int)rlen,
meta->flags);
}
}
fprintf(stderr, "ws: curl_ws_recv returned %u, received %u\n",
(unsigned int)result, (unsigned int)rlen);
return (int)result;
}
static int recv_any(CURL *curl)
{
size_t rlen;
const struct curl_ws_frame *meta;
char buffer[256];
CURLcode result = curl_ws_recv(curl, buffer, sizeof(buffer), &rlen, &meta);
if(result)
return result;
return 0;
}
/* close the connection */
static void websocket_close(CURL *curl)
{
size_t sent;
(void)curl_ws_send(curl, "", 0, &sent, 0, CURLWS_CLOSE);
}
static void websocket(CURL *curl)
{
int i = 0;
do {
recv_any(curl);
if(ping(curl, "foobar"))
return;
if(recv_pong(curl, "foobar")) {
return;
}
sleep(2);
} while(i++ < 10);
websocket_close(curl);
}
int main(void)
{
CURL *curl;
CURLcode res;
curl = curl_easy_init();
if(curl) {
curl_easy_setopt(curl, CURLOPT_URL, "wss://example.com");
curl_easy_setopt(curl, CURLOPT_CONNECT_ONLY, 2L); /* websocket style */
/* Perform the request, res will get the return code */
res = curl_easy_perform(curl);
/* Check for errors */
if(res != CURLE_OK)
fprintf(stderr, "curl_easy_perform() failed: %s\n",
curl_easy_strerror(res));
else {
/* connected and ready */
websocket(curl);
}
/* always cleanup */
curl_easy_cleanup(curl);
}
return 0;
}
|
