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1/* -*- linux-c -*- ------------------------------------------------------- *
2 *
3 * Copyright (C) 1991, 1992 Linus Torvalds
4 * Copyright 2007 rPath, Inc. - All Rights Reserved
5 *
6 * This file is part of the Linux kernel, and is made available under
7 * the terms of the GNU General Public License version 2.
8 *
9 * ----------------------------------------------------------------------- */
10
11/*
12 * Very basic string functions
13 */
14
15#include "boot.h"
16
17int strcmp(const char *str1, const char *str2)
18{
19 const unsigned char *s1 = (const unsigned char *)str1;
20 const unsigned char *s2 = (const unsigned char *)str2;
21 int delta = 0;
22
23 while (*s1 || *s2) {
24 delta = *s2 - *s1;
25 if (delta)
26 return delta;
27 s1++;
28 s2++;
29 }
30 return 0;
31}
32
33int strncmp(const char *cs, const char *ct, size_t count)
34{
35 unsigned char c1, c2;
36
37 while (count) {
38 c1 = *cs++;
39 c2 = *ct++;
40 if (c1 != c2)
41 return c1 < c2 ? -1 : 1;
42 if (!c1)
43 break;
44 count--;
45 }
46 return 0;
47}
48
49size_t strnlen(const char *s, size_t maxlen)
50{
51 const char *es = s;
52 while (*es && maxlen) {
53 es++;
54 maxlen--;
55 }
56
57 return (es - s);
58}
59
60unsigned int atou(const char *s)
61{
62 unsigned int i = 0;
63 while (isdigit(*s))
64 i = i * 10 + (*s++ - '0');
65 return i;
66}
67
68/* Works only for digits and letters, but small and fast */
69#define TOLOWER(x) ((x) | 0x20)
70
71static unsigned int simple_guess_base(const char *cp)
72{
73 if (cp[0] == '0') {
74 if (TOLOWER(cp[1]) == 'x' && isxdigit(cp[2]))
75 return 16;
76 else
77 return 8;
78 } else {
79 return 10;
80 }
81}
82
83/**
84 * simple_strtoull - convert a string to an unsigned long long
85 * @cp: The start of the string
86 * @endp: A pointer to the end of the parsed string will be placed here
87 * @base: The number base to use
88 */
89
90unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
91{
92 unsigned long long result = 0;
93
94 if (!base)
95 base = simple_guess_base(cp);
96
97 if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
98 cp += 2;
99
100 while (isxdigit(*cp)) {
101 unsigned int value;
102
103 value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;
104 if (value >= base)
105 break;
106 result = result * base + value;
107 cp++;
108 }
109 if (endp)
110 *endp = (char *)cp;
111
112 return result;
113}
1/* -*- linux-c -*- ------------------------------------------------------- *
2 *
3 * Copyright (C) 1991, 1992 Linus Torvalds
4 * Copyright 2007 rPath, Inc. - All Rights Reserved
5 *
6 * This file is part of the Linux kernel, and is made available under
7 * the terms of the GNU General Public License version 2.
8 *
9 * ----------------------------------------------------------------------- */
10
11/*
12 * Very basic string functions
13 */
14
15#include <linux/types.h>
16#include "ctype.h"
17
18int memcmp(const void *s1, const void *s2, size_t len)
19{
20 u8 diff;
21 asm("repe; cmpsb; setnz %0"
22 : "=qm" (diff), "+D" (s1), "+S" (s2), "+c" (len));
23 return diff;
24}
25
26int strcmp(const char *str1, const char *str2)
27{
28 const unsigned char *s1 = (const unsigned char *)str1;
29 const unsigned char *s2 = (const unsigned char *)str2;
30 int delta = 0;
31
32 while (*s1 || *s2) {
33 delta = *s1 - *s2;
34 if (delta)
35 return delta;
36 s1++;
37 s2++;
38 }
39 return 0;
40}
41
42int strncmp(const char *cs, const char *ct, size_t count)
43{
44 unsigned char c1, c2;
45
46 while (count) {
47 c1 = *cs++;
48 c2 = *ct++;
49 if (c1 != c2)
50 return c1 < c2 ? -1 : 1;
51 if (!c1)
52 break;
53 count--;
54 }
55 return 0;
56}
57
58size_t strnlen(const char *s, size_t maxlen)
59{
60 const char *es = s;
61 while (*es && maxlen) {
62 es++;
63 maxlen--;
64 }
65
66 return (es - s);
67}
68
69unsigned int atou(const char *s)
70{
71 unsigned int i = 0;
72 while (isdigit(*s))
73 i = i * 10 + (*s++ - '0');
74 return i;
75}
76
77/* Works only for digits and letters, but small and fast */
78#define TOLOWER(x) ((x) | 0x20)
79
80static unsigned int simple_guess_base(const char *cp)
81{
82 if (cp[0] == '0') {
83 if (TOLOWER(cp[1]) == 'x' && isxdigit(cp[2]))
84 return 16;
85 else
86 return 8;
87 } else {
88 return 10;
89 }
90}
91
92/**
93 * simple_strtoull - convert a string to an unsigned long long
94 * @cp: The start of the string
95 * @endp: A pointer to the end of the parsed string will be placed here
96 * @base: The number base to use
97 */
98
99unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
100{
101 unsigned long long result = 0;
102
103 if (!base)
104 base = simple_guess_base(cp);
105
106 if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
107 cp += 2;
108
109 while (isxdigit(*cp)) {
110 unsigned int value;
111
112 value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;
113 if (value >= base)
114 break;
115 result = result * base + value;
116 cp++;
117 }
118 if (endp)
119 *endp = (char *)cp;
120
121 return result;
122}
123
124/**
125 * strlen - Find the length of a string
126 * @s: The string to be sized
127 */
128size_t strlen(const char *s)
129{
130 const char *sc;
131
132 for (sc = s; *sc != '\0'; ++sc)
133 /* nothing */;
134 return sc - s;
135}
136
137/**
138 * strstr - Find the first substring in a %NUL terminated string
139 * @s1: The string to be searched
140 * @s2: The string to search for
141 */
142char *strstr(const char *s1, const char *s2)
143{
144 size_t l1, l2;
145
146 l2 = strlen(s2);
147 if (!l2)
148 return (char *)s1;
149 l1 = strlen(s1);
150 while (l1 >= l2) {
151 l1--;
152 if (!memcmp(s1, s2, l2))
153 return (char *)s1;
154 s1++;
155 }
156 return NULL;
157}