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
|
/*
* Ouroboros - Copyright (C) 2016 - 2020
*
* A simple echo application
*
* Dimitri Staessens <dimitri.staessens@ugent.be>
* Sander Vrijders <sander.vrijders@ugent.be>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* 3. Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#define _POSIX_C_SOURCE 199309L
#include <ouroboros/dev.h>
#include <stdio.h>
#include <string.h>
#define BUF_SIZE 256
static void usage(void)
{
printf("Usage: oecho [OPTION]...\n"
"Sends an echo between a server and a client\n\n"
" -l, --listen Run in server mode\n"
" --help Display this help text and exit\n");
}
static int server_main(void)
{
int fd = 0;
char buf[BUF_SIZE];
ssize_t count = 0;
printf("Starting the server.\n");
while (true) {
fd = flow_accept(NULL, NULL);
if (fd < 0) {
printf("Failed to accept flow.\n");
break;
}
printf("New flow.\n");
count = flow_read(fd, &buf, BUF_SIZE);
if (count < 0) {
printf("Failed to read packet.\n");
flow_dealloc(fd);
continue;
}
printf("Message from client is %.*s.\n", (int) count, buf);
if (flow_write(fd, buf, count) == -1) {
printf("Failed to write packet.\n");
flow_dealloc(fd);
continue;
}
flow_dealloc(fd);
}
return 0;
}
static int client_main(void)
{
int fd = 0;
char buf[BUF_SIZE];
char * message = "Client says hi!";
ssize_t count = 0;
fd = flow_alloc("oecho", NULL, NULL);
if (fd < 0) {
printf("Failed to allocate flow.\n");
return -1;
}
if (flow_write(fd, message, strlen(message) + 1) < 0) {
printf("Failed to write packet.\n");
flow_dealloc(fd);
return -1;
}
count = flow_read(fd, buf, BUF_SIZE);
if (count < 0) {
printf("Failed to read packet.\n");
flow_dealloc(fd);
return -1;
}
printf("Server replied with %.*s\n", (int) count, buf);
flow_dealloc(fd);
return 0;
}
int main(int argc, char ** argv)
{
int ret = -1;
bool server = false;
argc--;
argv++;
while (argc > 0) {
if (strcmp(*argv, "-l") == 0 ||
strcmp(*argv, "--listen") == 0) {
server = true;
} else {
usage();
return 0;
}
argc--;
argv++;
}
if (server)
ret = server_main();
else
ret = client_main();
return ret;
}
|
