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
|
/*
* Copyright (c) 2007 Michael Niedermayer
*
* This file is part of Libav.
*
* Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>
#include <errno.h>
#include <string.h>
static uint32_t state;
static uint32_t ran(void)
{
return state = state * 1664525 + 1013904223;
}
int main(int argc, char **argv)
{
FILE *f;
int count, maxburst, length;
if (argc < 5) {
printf("USAGE: trasher <filename> <count> <maxburst> <seed>\n");
return 1;
}
f = fopen(argv[1], "rb+");
if (!f) {
perror(argv[1]);
return 2;
}
count = atoi(argv[2]);
maxburst = atoi(argv[3]);
state = atoi(argv[4]);
fseek(f, 0, SEEK_END);
length = ftell(f);
fseek(f, 0, SEEK_SET);
while (count--) {
int burst = 1 + ran() * (uint64_t) (abs(maxburst) - 1) / UINT32_MAX;
int pos = ran() * (uint64_t) length / UINT32_MAX;
fseek(f, pos, SEEK_SET);
if (maxburst < 0)
burst = -maxburst;
if (pos + burst > length)
continue;
while (burst--) {
int val = ran() * 256ULL / UINT32_MAX;
if (maxburst < 0)
val = 0;
fwrite(&val, 1, 1, f);
}
}
return 0;
}
|
