xref: /openbmc/linux/arch/s390/boot/string.c (revision 49698745)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/ctype.h>
3 #include <linux/kernel.h>
4 #include "../lib/string.c"
5 
6 int strncmp(const char *cs, const char *ct, size_t count)
7 {
8 	unsigned char c1, c2;
9 
10 	while (count) {
11 		c1 = *cs++;
12 		c2 = *ct++;
13 		if (c1 != c2)
14 			return c1 < c2 ? -1 : 1;
15 		if (!c1)
16 			break;
17 		count--;
18 	}
19 	return 0;
20 }
21 
22 char *skip_spaces(const char *str)
23 {
24 	while (isspace(*str))
25 		++str;
26 	return (char *)str;
27 }
28 
29 char *strim(char *s)
30 {
31 	size_t size;
32 	char *end;
33 
34 	size = strlen(s);
35 	if (!size)
36 		return s;
37 
38 	end = s + size - 1;
39 	while (end >= s && isspace(*end))
40 		end--;
41 	*(end + 1) = '\0';
42 
43 	return skip_spaces(s);
44 }
45 
46 /* Works only for digits and letters, but small and fast */
47 #define TOLOWER(x) ((x) | 0x20)
48 
49 static unsigned int simple_guess_base(const char *cp)
50 {
51 	if (cp[0] == '0') {
52 		if (TOLOWER(cp[1]) == 'x' && isxdigit(cp[2]))
53 			return 16;
54 		else
55 			return 8;
56 	} else {
57 		return 10;
58 	}
59 }
60 
61 /**
62  * simple_strtoull - convert a string to an unsigned long long
63  * @cp: The start of the string
64  * @endp: A pointer to the end of the parsed string will be placed here
65  * @base: The number base to use
66  */
67 
68 unsigned long long simple_strtoull(const char *cp, char **endp,
69 				   unsigned int base)
70 {
71 	unsigned long long result = 0;
72 
73 	if (!base)
74 		base = simple_guess_base(cp);
75 
76 	if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
77 		cp += 2;
78 
79 	while (isxdigit(*cp)) {
80 		unsigned int value;
81 
82 		value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;
83 		if (value >= base)
84 			break;
85 		result = result * base + value;
86 		cp++;
87 	}
88 	if (endp)
89 		*endp = (char *)cp;
90 
91 	return result;
92 }
93 
94 long simple_strtol(const char *cp, char **endp, unsigned int base)
95 {
96 	if (*cp == '-')
97 		return -simple_strtoull(cp + 1, endp, base);
98 
99 	return simple_strtoull(cp, endp, base);
100 }
101