1 /* Copyright (C) 2003-2022 Free Software Foundation, Inc.
2    This file is part of the GNU C Library.
3 
4    The GNU C Library is free software; you can redistribute it and/or
5    modify it under the terms of the GNU Lesser General Public
6    License as published by the Free Software Foundation; either
7    version 2.1 of the License, or (at your option) any later version.
8 
9    The GNU C Library is distributed in the hope that it will be useful,
10    but WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12    Lesser General Public License for more details.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library; if not, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #include <errno.h>
19 #include <stdio.h>
20 #include <unistd.h>
21 
22 
23 /* Test that nice() does not incorrectly return 0.  */
24 static int
do_test(void)25 do_test (void)
26 {
27   int ret;
28   const int incr = 10;
29   int old;
30 
31   /* Discover current nice value.  */
32   errno = 0;
33   old = nice (0);
34   if (old == -1 && errno != 0)
35     {
36       printf ("break: nice(%d) return: %d, %m\n", 0, old);
37       return 1;
38     }
39 
40   /* Nice ourselves up.  */
41   errno = 0;
42   ret = nice (incr);
43   if (ret == -1 && errno != 0)
44     {
45       printf ("break: nice(%d) return: %d, %m\n", incr, ret);
46       return 1;
47     }
48 
49   /* Check for return value being zero when it shouldn't.  Cannot simply
50      check for expected value since nice values are capped at 2^n-1.
51      But we assume that we didn't start at the cap and so should have
52      increased some.  */
53   if (ret <= old)
54     {
55       printf ("FAIL: retval (%d) of nice(%d) != %d\n", ret, incr, old + incr);
56       return 1;
57     }
58 
59   /* BZ #18086. Make sure we don't reset errno.  */
60   errno = EBADF;
61   nice (0);
62   if (errno != EBADF)
63     {
64       printf ("FAIL: errno = %i, but wanted EBADF (%i)\n", errno, EBADF);
65       return 1;
66     }
67 
68 
69   printf ("PASS: nice(%d) from %d return: %d\n", incr, old, ret);
70   return 0;
71 }
72 
73 #define TEST_FUNCTION do_test ()
74 #include "../test-skeleton.c"
75