glibc/string/strfry.c
Zack Weinberg 1baae4aa6f
Don't use the argument to time.
It doesn't make sense to remove all the internal uses of time.
It's still a standard ISO C function, and its callers don't need
sub-second resolution and would be unnecessarily complicated if
they had to declare a struct timespec instead of just a time_t.
However, a handful of places were using the vestigial "result"
argument instead of the return value, which is slightly less
efficient and also looks strange.  Correct this.

	* misc/syslog.c (__vsyslog_internal)
	* time/getdate.c (__getdate_r)
	* time/tst_wcsftime.c (main):
	Use return value of time, not its argument.

	* string/strfry.c (strfry)
	* sysdeps/mach/sleep.c (__sleep):
	Remove unnecessary casts of NULL in calls to time.
2019-08-21 08:26:36 -04:00

53 lines
1.4 KiB
C

/* Copyright (C) 1992-2019 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <string.h>
#include <stdlib.h>
#include <time.h>
#include <unistd.h>
char *
strfry (char *string)
{
static int init;
static struct random_data rdata;
if (!init)
{
static char state[32];
rdata.state = NULL;
__initstate_r (time (NULL) ^ getpid (),
state, sizeof (state), &rdata);
init = 1;
}
size_t len = strlen (string);
if (len > 0)
for (size_t i = 0; i < len - 1; ++i)
{
int32_t j;
__random_r (&rdata, &j);
j = j % (len - i) + i;
char c = string[i];
string[i] = string[j];
string[j] = c;
}
return string;
}