1/* Hardware capability support for run-time dynamic loader. String splitting.
2 Copyright (C) 2020-2023 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#include <dl-hwcaps.h>
20#include <stdbool.h>
21#include <string.h>
22
23_Bool
24_dl_hwcaps_split (struct dl_hwcaps_split *s)
25{
26 if (s->segment == NULL)
27 return false;
28
29 /* Skip over the previous segment. */
30 s->segment += s->length;
31
32 /* Consume delimiters. This also avoids returning an empty
33 segment. */
34 while (*s->segment == ':')
35 ++s->segment;
36 if (*s->segment == '\0')
37 return false;
38
39 /* This could use strchrnul, but we would have to link the function
40 into ld.so for that. */
41 const char *colon = strchr (s->segment, ':');
42 if (colon == NULL)
43 s->length = strlen (s->segment);
44 else
45 s->length = colon - s->segment;
46 return true;
47}
48
49_Bool
50_dl_hwcaps_split_masked (struct dl_hwcaps_split_masked *s)
51{
52 while (true)
53 {
54 if (!_dl_hwcaps_split (&s->split))
55 return false;
56 bool active = s->bitmask & 1;
57 s->bitmask >>= 1;
58 if (active && _dl_hwcaps_contains (s->mask,
59 s->split.segment, s->split.length))
60 return true;
61 }
62}
63
64_Bool
65_dl_hwcaps_contains (const char *hwcaps, const char *name, size_t name_length)
66{
67 if (hwcaps == NULL)
68 return true;
69
70 struct dl_hwcaps_split split;
71 _dl_hwcaps_split_init (&split, hwcaps);
72 while (_dl_hwcaps_split (&split))
73 if (split.length == name_length
74 && memcmp (split.segment, name, name_length) == 0)
75 return true;
76 return false;
77}
78