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1/*
2 * linux/tools/lib/string.c
3 *
4 * Copied from linux/lib/string.c, where it is:
5 *
6 * Copyright (C) 1991, 1992 Linus Torvalds
7 *
8 * More specifically, the first copied function was strtobool, which
9 * was introduced by:
10 *
11 * d0f1fed29e6e ("Add a strtobool function matching semantics of existing in kernel equivalents")
12 * Author: Jonathan Cameron <jic23@cam.ac.uk>
13 */
14
15#include <stdlib.h>
16#include <string.h>
17#include <errno.h>
18#include <linux/string.h>
19#include <linux/compiler.h>
20
21/**
22 * memdup - duplicate region of memory
23 *
24 * @src: memory region to duplicate
25 * @len: memory region length
26 */
27void *memdup(const void *src, size_t len)
28{
29 void *p = malloc(len);
30
31 if (p)
32 memcpy(p, src, len);
33
34 return p;
35}
36
37/**
38 * strtobool - convert common user inputs into boolean values
39 * @s: input string
40 * @res: result
41 *
42 * This routine returns 0 iff the first character is one of 'Yy1Nn0', or
43 * [oO][NnFf] for "on" and "off". Otherwise it will return -EINVAL. Value
44 * pointed to by res is updated upon finding a match.
45 */
46int strtobool(const char *s, bool *res)
47{
48 if (!s)
49 return -EINVAL;
50
51 switch (s[0]) {
52 case 'y':
53 case 'Y':
54 case '1':
55 *res = true;
56 return 0;
57 case 'n':
58 case 'N':
59 case '0':
60 *res = false;
61 return 0;
62 case 'o':
63 case 'O':
64 switch (s[1]) {
65 case 'n':
66 case 'N':
67 *res = true;
68 return 0;
69 case 'f':
70 case 'F':
71 *res = false;
72 return 0;
73 default:
74 break;
75 }
76 default:
77 break;
78 }
79
80 return -EINVAL;
81}
82
83/**
84 * strlcpy - Copy a C-string into a sized buffer
85 * @dest: Where to copy the string to
86 * @src: Where to copy the string from
87 * @size: size of destination buffer
88 *
89 * Compatible with *BSD: the result is always a valid
90 * NUL-terminated string that fits in the buffer (unless,
91 * of course, the buffer size is zero). It does not pad
92 * out the result like strncpy() does.
93 *
94 * If libc has strlcpy() then that version will override this
95 * implementation:
96 */
97size_t __weak strlcpy(char *dest, const char *src, size_t size)
98{
99 size_t ret = strlen(src);
100
101 if (size) {
102 size_t len = (ret >= size) ? size - 1 : ret;
103 memcpy(dest, src, len);
104 dest[len] = '\0';
105 }
106 return ret;
107}