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
|
/*
* Invoke gsmstack() with any kind of burst. Automaticly decode and retrieve
* information.
*/
#include "system.h"
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "gsmstack.h"
#include "gsm_constants.h"
#include "interleave.h"
#include "sch.h"
INTERLEAVE_CTX ictx;
static void
diff_decode(char *dst, char *src, int len)
{
const unsigned char *end = src + len;
unsigned char last;
src += 3;
last = 0;
memset(dst, 0, 3);
dst += 3;
while (src < end)
{
*dst = !*src ^ last;
last = *dst;
src++;
dst++;
}
}
/*
* Initialize a new GSMSTACK context.
*/
int
GS_new(GS_CTX *ctx)
{
memset(ctx, 0, sizeof *ctx);
interleave_init(&ictx, 456, 114);
return 0;
}
/*
* 156 bit
*/
int
GS_process(GS_CTX *ctx, int ts, int type, char *data)
{
int fn;
int bsic;
int ret;
char buf[156];
diff_decode(buf, data, 156);
switch (type)
{
case SCH:
ret = decode_sch(buf, &fn, &bsic);
if (ret != 0)
break;
DEBUGF("FN %d, BSIC %d\n", fn, bsic);
break;
case NORMAL:
break;
}
}
|
