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
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
|
/*
* lws-minimal-raw-file
*
* Written in 2010-2019 by Andy Green <andy@warmcat.com>
*
* This file is made available under the Creative Commons CC0 1.0
* Universal Public Domain Dedication.
*
* This demonstrates adopting a file descriptor into the lws event
* loop.
*/
#include <libwebsockets.h>
#include <string.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
struct raw_vhd {
// lws_sock_file_fd_type u;
int filefd;
};
static char filepath[256];
static int
callback_raw_test(struct lws *wsi, enum lws_callback_reasons reason,
void *user, void *in, size_t len)
{
struct raw_vhd *vhd = (struct raw_vhd *)lws_protocol_vh_priv_get(
lws_get_vhost(wsi), lws_get_protocol(wsi));
lws_sock_file_fd_type u;
uint8_t buf[1024];
int n;
switch (reason) {
case LWS_CALLBACK_PROTOCOL_INIT:
vhd = lws_protocol_vh_priv_zalloc(lws_get_vhost(wsi),
lws_get_protocol(wsi), sizeof(struct raw_vhd));
vhd->filefd = lws_open(filepath, O_RDWR);
if (vhd->filefd == -1) {
lwsl_err("Unable to open %s\n", filepath);
return 1;
}
u.filefd = (lws_filefd_type)(long long)vhd->filefd;
if (!lws_adopt_descriptor_vhost(lws_get_vhost(wsi),
LWS_ADOPT_RAW_FILE_DESC, u,
"raw-test", NULL)) {
lwsl_err("Failed to adopt fifo descriptor\n");
close(vhd->filefd);
vhd->filefd = -1;
return 1;
}
break;
case LWS_CALLBACK_PROTOCOL_DESTROY:
if (vhd && vhd->filefd != -1)
close(vhd->filefd);
break;
/* callbacks related to raw file descriptor */
case LWS_CALLBACK_RAW_ADOPT_FILE:
lwsl_notice("LWS_CALLBACK_RAW_ADOPT_FILE\n");
break;
case LWS_CALLBACK_RAW_RX_FILE:
lwsl_notice("LWS_CALLBACK_RAW_RX_FILE\n");
n = (int)read(vhd->filefd, buf, sizeof(buf));
if (n < 0) {
lwsl_err("Reading from %s failed\n", filepath);
return 1;
}
lwsl_hexdump_level(LLL_NOTICE, buf, (unsigned int)n);
break;
case LWS_CALLBACK_RAW_CLOSE_FILE:
lwsl_notice("LWS_CALLBACK_RAW_CLOSE_FILE\n");
break;
case LWS_CALLBACK_RAW_WRITEABLE_FILE:
lwsl_notice("LWS_CALLBACK_RAW_WRITEABLE_FILE\n");
/*
* you can call lws_callback_on_writable() on a raw file wsi as
* usual, and then write directly into the raw filefd here.
*/
break;
default:
break;
}
return 0;
}
static struct lws_protocols protocols[] = {
{ "raw-test", callback_raw_test, 0, 0, 0, NULL, 0 },
LWS_PROTOCOL_LIST_TERM
};
static int interrupted;
void sigint_handler(int sig)
{
interrupted = 1;
}
int main(int argc, const char **argv)
{
struct lws_context_creation_info info;
struct lws_context *context;
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 raw file\n");
if (argc < 2) {
lwsl_user("Usage: %s <file to monitor> "
" eg, /dev/ttyUSB0 or /dev/input/event0 or "
"/proc/self/fd/0\n", argv[0]);
return 1;
}
signal(SIGINT, sigint_handler);
memset(&info, 0, sizeof info); /* otherwise uninitialized garbage */
info.port = CONTEXT_PORT_NO_LISTEN_SERVER; /* no listen socket for demo */
info.protocols = protocols;
lws_strncpy(filepath, argv[1], sizeof(filepath));
context = lws_create_context(&info);
if (!context) {
lwsl_err("lws init failed\n");
return 1;
}
while (n >= 0 && !interrupted)
n = lws_service(context, 0);
lws_context_destroy(context);
return 0;
}
|
