1// SPDX-License-Identifier: GPL-2.0
  2#define IN_BOOT_STRING_C 1
  3#include <linux/ctype.h>
  4#include <linux/kernel.h>
  5#include <linux/errno.h>
  6#undef CONFIG_KASAN
  7#undef CONFIG_KASAN_GENERIC
  8#undef CONFIG_KMSAN
  9#include "../lib/string.c"
 10
 11/*
 12 * Duplicate some functions from the common lib/string.c
 13 * instead of fully including it.
 14 */
 15
 16int strncmp(const char *cs, const char *ct, size_t count)
 17{
 18	unsigned char c1, c2;
 19
 20	while (count) {
 21		c1 = *cs++;
 22		c2 = *ct++;
 23		if (c1 != c2)
 24			return c1 < c2 ? -1 : 1;
 25		if (!c1)
 26			break;
 27		count--;
 28	}
 29	return 0;
 30}
 31
 32void *memset64(uint64_t *s, uint64_t v, size_t count)
 33{
 34	uint64_t *xs = s;
 35
 36	while (count--)
 37		*xs++ = v;
 38	return s;
 39}
 40
 41char *skip_spaces(const char *str)
 42{
 43	while (isspace(*str))
 44		++str;
 45	return (char *)str;
 46}
 47
 48char *strim(char *s)
 49{
 50	size_t size;
 51	char *end;
 52
 53	size = strlen(s);
 54	if (!size)
 55		return s;
 56
 57	end = s + size - 1;
 58	while (end >= s && isspace(*end))
 59		end--;
 60	*(end + 1) = '\0';
 61
 62	return skip_spaces(s);
 63}
 64
 65/* Works only for digits and letters, but small and fast */
 66#define TOLOWER(x) ((x) | 0x20)
 67
 68static unsigned int simple_guess_base(const char *cp)
 69{
 70	if (cp[0] == '0') {
 71		if (TOLOWER(cp[1]) == 'x' && isxdigit(cp[2]))
 72			return 16;
 73		else
 74			return 8;
 75	} else {
 76		return 10;
 77	}
 78}
 79
 80/**
 81 * simple_strtoull - convert a string to an unsigned long long
 82 * @cp: The start of the string
 83 * @endp: A pointer to the end of the parsed string will be placed here
 84 * @base: The number base to use
 85 */
 86
 87unsigned long long simple_strtoull(const char *cp, char **endp,
 88				   unsigned int base)
 89{
 90	unsigned long long result = 0;
 91
 92	if (!base)
 93		base = simple_guess_base(cp);
 94
 95	if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
 96		cp += 2;
 97
 98	while (isxdigit(*cp)) {
 99		unsigned int value;
100
101		value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;
102		if (value >= base)
103			break;
104		result = result * base + value;
105		cp++;
106	}
107	if (endp)
108		*endp = (char *)cp;
109
110	return result;
111}
112
113long simple_strtol(const char *cp, char **endp, unsigned int base)
114{
115	if (*cp == '-')
116		return -simple_strtoull(cp + 1, endp, base);
117
118	return simple_strtoull(cp, endp, base);
119}
120
121int kstrtobool(const char *s, bool *res)
122{
123	if (!s)
124		return -EINVAL;
125
126	switch (s[0]) {
127	case 'y':
128	case 'Y':
129	case '1':
130		*res = true;
131		return 0;
132	case 'n':
133	case 'N':
134	case '0':
135		*res = false;
136		return 0;
137	case 'o':
138	case 'O':
139		switch (s[1]) {
140		case 'n':
141		case 'N':
142			*res = true;
143			return 0;
144		case 'f':
145		case 'F':
146			*res = false;
147			return 0;
148		default:
149			break;
150		}
151	default:
152		break;
153	}
154
155	return -EINVAL;
156}