desktop-tools/siprandom.c

89 lines
2.3 KiB
C

/*
* siprandom.c: relatively fast pseudo-random data generator
*
* Copyright (c) 2016, Přemysl Eric Janouch <p@janouch.name>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR 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.
*
*/
#include "config.h"
#undef PROGRAM_NAME
#define PROGRAM_NAME "siprandom"
#include "liberty/liberty.c"
static void
parse_program_arguments (int argc, char **argv)
{
static const struct opt opts[] =
{
{ 'd', "debug", NULL, 0, "run in debug mode" },
{ 'h', "help", NULL, 0, "display this help and exit" },
{ 'V', "version", NULL, 0, "output version information and exit" },
{ 0, NULL, NULL, 0, NULL }
};
struct opt_handler oh =
opt_handler_make (argc, argv, opts, NULL, "PRNG.");
int c;
while ((c = opt_handler_get (&oh)) != -1)
switch (c)
{
case 'd':
g_debug_mode = true;
break;
case 'h':
opt_handler_usage (&oh, stdout);
exit (EXIT_SUCCESS);
case 'V':
printf (PROGRAM_NAME " " PROGRAM_VERSION "\n");
exit (EXIT_SUCCESS);
default:
print_error ("wrong options");
opt_handler_usage (&oh, stderr);
exit (EXIT_FAILURE);
}
argc -= optind;
argv += optind;
if (argc)
{
opt_handler_usage (&oh, stderr);
exit (EXIT_FAILURE);
}
opt_handler_free (&oh);
}
int
main (int argc, char *argv[])
{
parse_program_arguments (argc, argv);
uint64_t counter, hash;
struct error *e = NULL;
if (!random_bytes (g_siphash_key, sizeof g_siphash_key, &e)
|| !random_bytes (&counter, sizeof counter, &e)
|| !random_bytes (&hash, sizeof hash, &e))
exit_fatal ("%s: %s", "failed to obtain random data seed", e->message);
do
{
hash ^= siphash_wrapper (&counter, sizeof counter);
counter++;
}
while (fwrite (&hash, sizeof hash, 1, stdout) == 1);
return EXIT_SUCCESS;
}