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[libav.git] / tools / trasher.c
1 /*
2 * Copyright (c) 2007 Michael Niedermayer
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 #define _XOPEN_SOURCE 600
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include <time.h>
25 #include <inttypes.h>
26
27 int main(int argc, char** argv)
28 {
29 FILE *f;
30 int count, maxburst, length;
31
32 if (argc < 4){
33 printf("USAGE: trasher <filename> <count> <maxburst>\n");
34 return 1;
35 }
36
37 f= fopen(argv[1], "rb+");
38 if (!f){
39 perror(argv[1]);
40 return 2;
41 }
42 count= atoi(argv[2]);
43 maxburst= atoi(argv[3]);
44
45 srandom (time (0));
46
47 fseek(f, 0, SEEK_END);
48 length= ftell(f);
49 fseek(f, 0, SEEK_SET);
50
51 while(count--){
52 int burst= 1 + random() * (uint64_t) (abs(maxburst)-1) / RAND_MAX;
53 int pos= random() * (uint64_t) length / RAND_MAX;
54 fseek(f, pos, SEEK_SET);
55
56 if(maxburst<0) burst= -maxburst;
57
58 if(pos + burst > length)
59 continue;
60
61 while(burst--){
62 int val= random() * 256ULL / RAND_MAX;
63
64 if(maxburst<0) val=0;
65
66 fwrite(&val, 1, 1, f);
67 }
68 }
69
70 return 0;
71 }