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
|
/*
* See http://www.asterisk.org for more information about
* the Asterisk project. Please do not directly contact
* any of the maintainers of this project for assistance;
* the project provides a web site, mailing lists and IRC
* channels for your use.
*
* This program is free software, distributed under the terms of
* the GNU General Public License Version 2 as published by the
* Free Software Foundation. See the LICENSE file included with
* this program for more details.
*/
#define FAST_HDLC_NEED_TABLES
#include "kernel/fasthdlc.h"
#include <stdio.h>
#include <fcntl.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#define RANDOM "/dev/urandom" /* Not genuinely random */
/* #define RANDOM "/dev/random" */ /* Quite genuinely random */
int myread(int fd, char *buf, int len)
{
int sofar;
int res;
sofar = 0;
while(sofar < len) {
res = read(fd, buf + sofar, len - sofar);
if (res < 0)
return res;
sofar += res;
}
return sofar;
}
int main(int argc, char *argv[])
{
unsigned char buf[1024];
unsigned char outbuf[2048];
int res;
int randin;
int randout;
int hdlcout;
int cnt;
int hdlccnt;
int x;
int flags;
struct fasthdlc_state transmitter;
fasthdlc_precalc();
fasthdlc_init(&transmitter);
randin = open(RANDOM, O_RDONLY);
if (randin < 0) {
fprintf(stderr, "Unable to open %s: %s\n", RANDOM, strerror(errno));
exit(1);
}
randout = open("random.raw", O_WRONLY|O_TRUNC|O_CREAT, 0666);
if (randout < 0) {
fprintf(stderr, "Unable to open random.raw: %s\n", strerror(errno));
exit(1);
}
hdlcout = open("random.hdlc", O_WRONLY|O_TRUNC|O_CREAT, 0666);
if (hdlcout < 0) {
fprintf(stderr, "Unable to open random.hdlc: %s\n", strerror(errno));
exit(1);
}
for (;;) {
cnt = (rand() % 256) + 4; /* Read a pseudo-random amount of stuff */
res = myread(randin, buf, cnt);
if (res != cnt) {
fprintf(stderr, "Tried to read %d bytes, but read %d instead\n", cnt, res);
exit(1);
}
res = write(randout, buf, cnt);
if (res != cnt) {
fprintf(stderr, "Tried to write %d bytes, but wrote %d instead\n", cnt, res);
exit(1);
}
/* HDLC encode */
hdlccnt = 0;
/* Start with a flag */
fasthdlc_tx_frame(&transmitter);
if (transmitter.bits >= 8)
outbuf[hdlccnt++] = fasthdlc_tx_run(&transmitter);
for (x=0;x<cnt;x++) {
res = fasthdlc_tx_load(&transmitter, buf[x]);
if (res < 0) {
fprintf(stderr, "Unable to load byte :(\n");
exit(1);
}
while(transmitter.bits >= 8) {
outbuf[hdlccnt++] = fasthdlc_tx_run(&transmitter);
}
}
flags = (rand() % 4);
for (x=0;x<flags;x++) {
if (transmitter.bits < 8)
fasthdlc_tx_frame(&transmitter);
else
fprintf(stderr, "Huh? Don't need a frame?\n");
outbuf[hdlccnt++] = fasthdlc_tx_run(&transmitter);
}
if (argc > 1)
printf("Encoded %d byte message with %d bytes of HDLC and %d extra flags\n", cnt, hdlccnt, flags);
res = write(hdlcout, outbuf, hdlccnt);
if (res != hdlccnt) {
fprintf(stderr, "Tried to write %d HDLC bytes, but wrote %d instead\n", cnt, res);
exit(1);
}
}
}
|
