genrandom.c revision 70e5a7403f0e0a3bd292b8287c5fed5772c15270
/*
* Copyright (C) 2004, 2005, 2007 Internet Systems Consortium, Inc. ("ISC")
* Copyright (C) 2000-2003 Internet Software Consortium.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*/
/* $Id: genrandom.c,v 1.15 2007/06/19 23:46:59 tbox Exp $ */
/*! \file */
#include <config.h>
#include <stdio.h>
#include <time.h>
#include <isc/stdlib.h>
int
main(int argc, char **argv) {
unsigned int bytes;
unsigned int k;
char *endp;
FILE *fp;
if (argc != 3) {
printf("usage: genrandom k file\n");
exit(1);
}
k = strtoul(argv[1], &endp, 10);
if (*endp != 0) {
printf("usage: genrandom k file\n");
exit(1);
}
bytes = k << 10;
fp = fopen(argv[2], "w");
if (fp == NULL) {
printf("failed to open %s\n", argv[2]);
exit(1);
}
#ifndef HAVE_ARC4RANDOM
srand(0x12345678);
#endif
while (bytes > 0) {
#ifndef HAVE_ARC4RANDOM
unsigned short int x = (rand() & 0xFFFF);
#else
unsigned short int x = (arc4random() & 0xFFFF);
#endif
unsigned char c = x & 0xFF;
if (putc(c, fp) == EOF) {
printf("error writing to file\n");
exit(1);
}
c = x >> 8;
if (putc(c, fp) == EOF) {
printf("error writing to file\n");
exit(1);
}
bytes -= 2;
}
fclose(fp);
return (0);
}