unplugged-system/external/ltp/testcases/kernel/syscalls/nice/nice01.c

71 lines
1.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (c) International Business Machines Corp., 2001
* Ported to LTP: Wayne Boyer
* Copyright (c) 2016 Cyril Hrubis <chrubis@suse.cz>
* Copyright (c) Linux Test Project, 2003-2022
*/
/*\
* [Description]
*
* Verify that root can provide a negative value to nice() system call and hence
* root can decrease the nice value of the process using nice().
*/
#include <unistd.h>
#include <errno.h>
#include <sys/resource.h>
#include "tst_test.h"
#define MIN_PRIO -20
static int nice_inc[] = {-1, -12, -50};
static void verify_nice(unsigned int i)
{
int new_nice;
int orig_nice;
int exp_nice;
int inc = nice_inc[i];
int delta;
orig_nice = SAFE_GETPRIORITY(PRIO_PROCESS, 0);
TEST(nice(inc));
exp_nice = MAX(MIN_PRIO, (orig_nice + inc));
if (TST_RET != exp_nice) {
tst_res(TFAIL | TTERRNO, "nice(%d) returned %li, expected %i",
inc, TST_RET, exp_nice);
return;
}
if (TST_ERR) {
tst_res(TFAIL | TTERRNO, "nice(%d) failed", inc);
return;
}
new_nice = SAFE_GETPRIORITY(PRIO_PROCESS, 0);
if (new_nice != exp_nice) {
tst_res(TFAIL, "Process priority %i, expected %i",
new_nice, exp_nice);
return;
}
tst_res(TPASS, "nice(%d) passed", inc);
delta = orig_nice - exp_nice;
TEST(nice(delta));
if (TST_ERR)
tst_brk(TBROK | TTERRNO, "nice(%d) failed", delta);
}
static struct tst_test test = {
.needs_root = 1,
.test = verify_nice,
.tcnt = ARRAY_SIZE(nice_inc),
};