1 /* Test that fadvise works as advertised.
2 Copyright (C) 2010-2023 Free Software Foundation, Inc.
3
4 This program is free software: you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 3 of the License, or
7 (at your option) any later version.
8
9 This program 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
12 GNU General Public License for more details.
13
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <https://www.gnu.org/licenses/>. */
16
17 /* Written by Pádraig Brady. */
18
19 #include <config.h>
20 #include <stdio.h>
21
22 #include "fadvise.h"
23
24 /* We ignore any errors as these hints are only advisory.
25 * There is the chance one can pass invalid ADVICE, which will
26 * not be indicated, but given the simplicity of the interface
27 * this is unlikely. Also not returning errors allows the
28 * unconditional passing of descriptors to non standard files,
29 * which will just be ignored if unsupported. */
30
31 int
main(void)32 main (void)
33 {
34 /* Valid. */
35 fadvise (stdin, FADVISE_SEQUENTIAL);
36 fdadvise (fileno (stdin), 0, 0, FADVISE_RANDOM);
37
38 /* Ignored. */
39 fadvise (nullptr, FADVISE_RANDOM);
40
41 /* Invalid. */
42 fdadvise (42, 0, 0, FADVISE_RANDOM);
43 /* Unfortunately C enums are not types.
44 One could hack type safety by wrapping in a struct,
45 but it's probably not worth the complexity in this case. */
46 fadvise (stdin, FADVISE_SEQUENTIAL + FADVISE_RANDOM);
47 fadvise (stdin, 4242);
48
49 return 0;
50 }
51