tools: K&R reformatting cosmetics
[libav.git] / tools / trasher.c
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1/*
2 * Copyright (c) 2007 Michael Niedermayer
3 *
2912e87a 4 * This file is part of Libav.
c33820e5 5 *
2912e87a 6 * Libav is free software; you can redistribute it and/or
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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 *
2912e87a 11 * Libav is distributed in the hope that it will be useful,
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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
2912e87a 17 * License along with Libav; if not, write to the Free Software
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18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
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20
21#include <stdio.h>
f19a068e 22#include <stdlib.h>
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23#include <inttypes.h>
24
47cf98ef 25static uint32_t state;
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26static uint32_t ran(void)
27{
28 return state = state * 1664525 + 1013904223;
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29}
30
4e81b5f5 31int main(int argc, char **argv)
0f340f8f 32{
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33 FILE *f;
34 int count, maxburst, length;
35
4e81b5f5 36 if (argc < 5) {
47cf98ef 37 printf("USAGE: trasher <filename> <count> <maxburst> <seed>\n");
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38 return 1;
39 }
40
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41 f = fopen(argv[1], "rb+");
42 if (!f) {
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43 perror(argv[1]);
44 return 2;
45 }
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46 count = atoi(argv[2]);
47 maxburst = atoi(argv[3]);
48 state = atoi(argv[4]);
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49
50 fseek(f, 0, SEEK_END);
4e81b5f5 51 length = ftell(f);
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52 fseek(f, 0, SEEK_SET);
53
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54 while (count--) {
55 int burst = 1 + ran() * (uint64_t) (abs(maxburst) - 1) / UINT32_MAX;
56 int pos = ran() * (uint64_t) length / UINT32_MAX;
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57 fseek(f, pos, SEEK_SET);
58
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59 if (maxburst < 0)
60 burst = -maxburst;
0f340f8f 61
4e81b5f5 62 if (pos + burst > length)
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63 continue;
64
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65 while (burst--) {
66 int val = ran() * 256ULL / UINT32_MAX;
0f340f8f 67
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68 if (maxburst < 0)
69 val = 0;
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70
71 fwrite(&val, 1, 1, f);
72 }
73 }
74
75 return 0;
76}