jcs.org
Serenity Operating System
1/*
2 * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
3 *
4 * SPDX-License-Identifier: BSD-2-Clause
5 */
6
7#include <AK/BuiltinWrappers.h>
8#include <assert.h>
9#include <ctype.h>
10#include <string.h>
11#include <strings.h>
12
13extern "C" {
14
15void bzero(void* dest, size_t n)
16{
17 memset(dest, 0, n);
18}
19
20void bcopy(void const* src, void* dest, size_t n)
21{
22 memmove(dest, src, n);
23}
24
25static char foldcase(char ch)
26{
27 if (isalpha(ch))
28 return tolower(ch);
29 return ch;
30}
31
32// https://pubs.opengroup.org/onlinepubs/9699919799/functions/strcasecmp.html
33int strcasecmp(char const* s1, char const* s2)
34{
35 for (; foldcase(*s1) == foldcase(*s2); ++s1, ++s2) {
36 if (*s1 == 0)
37 return 0;
38 }
39 return foldcase(*(unsigned char const*)s1) < foldcase(*(unsigned char const*)s2) ? -1 : 1;
40}
41
42// https://pubs.opengroup.org/onlinepubs/9699919799/functions/strncasecmp.html
43int strncasecmp(char const* s1, char const* s2, size_t n)
44{
45 if (!n)
46 return 0;
47 do {
48 if (foldcase(*s1) != foldcase(*s2++))
49 return foldcase(*(unsigned char const*)s1) - foldcase(*(unsigned char const*)--s2);
50 if (*s1++ == 0)
51 break;
52 } while (--n);
53 return 0;
54}
55
56// https://pubs.opengroup.org/onlinepubs/009696799/functions/ffs.html
57int ffs(int i)
58{
59 return bit_scan_forward(i);
60}
61
62// https://linux.die.net/man/3/ffsl (GNU extension)
63int ffsl(long int i)
64{
65 return bit_scan_forward(i);
66}
67
68// https://linux.die.net/man/3/ffsll (GNU extension)
69int ffsll(long long int i)
70{
71 return bit_scan_forward(i);
72}
73}