1// SPDX-License-Identifier: GPL-2.0
2#include <linux/ctype.h>
3#include <linux/kernel.h>
4#include <linux/errno.h>
5#undef CONFIG_KASAN
6#undef CONFIG_KASAN_GENERIC
7#include "../lib/string.c"
8
9int strncmp(const char *cs, const char *ct, size_t count)
10{
11	unsigned char c1, c2;
12
13	while (count) {
14		c1 = *cs++;
15		c2 = *ct++;
16		if (c1 != c2)
17			return c1 < c2 ? -1 : 1;
18		if (!c1)
19			break;
20		count--;
21	}
22	return 0;
23}
24
25char *skip_spaces(const char *str)
26{
27	while (isspace(*str))
28		++str;
29	return (char *)str;
30}
31
32char *strim(char *s)
33{
34	size_t size;
35	char *end;
36
37	size = strlen(s);
38	if (!size)
39		return s;
40
41	end = s + size - 1;
42	while (end >= s && isspace(*end))
43		end--;
44	*(end + 1) = '\0';
45
46	return skip_spaces(s);
47}
48
49/* Works only for digits and letters, but small and fast */
50#define TOLOWER(x) ((x) | 0x20)
51
52static unsigned int simple_guess_base(const char *cp)
53{
54	if (cp[0] == '0') {
55		if (TOLOWER(cp[1]) == 'x' && isxdigit(cp[2]))
56			return 16;
57		else
58			return 8;
59	} else {
60		return 10;
61	}
62}
63
64/**
65 * simple_strtoull - convert a string to an unsigned long long
66 * @cp: The start of the string
67 * @endp: A pointer to the end of the parsed string will be placed here
68 * @base: The number base to use
69 */
70
71unsigned long long simple_strtoull(const char *cp, char **endp,
72				   unsigned int base)
73{
74	unsigned long long result = 0;
75
76	if (!base)
77		base = simple_guess_base(cp);
78
79	if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
80		cp += 2;
81
82	while (isxdigit(*cp)) {
83		unsigned int value;
84
85		value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;
86		if (value >= base)
87			break;
88		result = result * base + value;
89		cp++;
90	}
91	if (endp)
92		*endp = (char *)cp;
93
94	return result;
95}
96
97long simple_strtol(const char *cp, char **endp, unsigned int base)
98{
99	if (*cp == '-')
100		return -simple_strtoull(cp + 1, endp, base);
101
102	return simple_strtoull(cp, endp, base);
103}
104
105int kstrtobool(const char *s, bool *res)
106{
107	if (!s)
108		return -EINVAL;
109
110	switch (s[0]) {
111	case 'y':
112	case 'Y':
113	case '1':
114		*res = true;
115		return 0;
116	case 'n':
117	case 'N':
118	case '0':
119		*res = false;
120		return 0;
121	case 'o':
122	case 'O':
123		switch (s[1]) {
124		case 'n':
125		case 'N':
126			*res = true;
127			return 0;
128		case 'f':
129		case 'F':
130			*res = false;
131			return 0;
132		default:
133			break;
134		}
135	default:
136		break;
137	}
138
139	return -EINVAL;
140}
141