Libav 0.7.1
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00001 /* 00002 * Copyright (c) 2007 Michael Niedermayer 00003 * 00004 * This file is part of Libav. 00005 * 00006 * Libav is free software; you can redistribute it and/or 00007 * modify it under the terms of the GNU Lesser General Public 00008 * License as published by the Free Software Foundation; either 00009 * version 2.1 of the License, or (at your option) any later version. 00010 * 00011 * Libav is distributed in the hope that it will be useful, 00012 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00013 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00014 * Lesser General Public License for more details. 00015 * 00016 * You should have received a copy of the GNU Lesser General Public 00017 * License along with Libav; if not, write to the Free Software 00018 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 00019 */ 00020 00021 #include <stdio.h> 00022 #include <stdlib.h> 00023 #include <inttypes.h> 00024 00025 static uint32_t state; 00026 static uint32_t ran(void){ 00027 return state= state*1664525+1013904223; 00028 } 00029 00030 int main(int argc, char** argv) 00031 { 00032 FILE *f; 00033 int count, maxburst, length; 00034 00035 if (argc < 5){ 00036 printf("USAGE: trasher <filename> <count> <maxburst> <seed>\n"); 00037 return 1; 00038 } 00039 00040 f= fopen(argv[1], "rb+"); 00041 if (!f){ 00042 perror(argv[1]); 00043 return 2; 00044 } 00045 count= atoi(argv[2]); 00046 maxburst= atoi(argv[3]); 00047 state= atoi(argv[4]); 00048 00049 fseek(f, 0, SEEK_END); 00050 length= ftell(f); 00051 fseek(f, 0, SEEK_SET); 00052 00053 while(count--){ 00054 int burst= 1 + ran() * (uint64_t) (abs(maxburst)-1) / UINT32_MAX; 00055 int pos= ran() * (uint64_t) length / UINT32_MAX; 00056 fseek(f, pos, SEEK_SET); 00057 00058 if(maxburst<0) burst= -maxburst; 00059 00060 if(pos + burst > length) 00061 continue; 00062 00063 while(burst--){ 00064 int val= ran() * 256ULL / UINT32_MAX; 00065 00066 if(maxburst<0) val=0; 00067 00068 fwrite(&val, 1, 1, f); 00069 } 00070 } 00071 00072 return 0; 00073 }