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 */ 27 void *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'. 43 * Otherwise it will return -EINVAL. Value pointed to by res is 44 * updated upon finding a match. 45 */ 46 int strtobool(const char *s, bool *res) 47 { 48 switch (s[0]) { 49 case 'y': 50 case 'Y': 51 case '1': 52 *res = true; 53 break; 54 case 'n': 55 case 'N': 56 case '0': 57 *res = false; 58 break; 59 default: 60 return -EINVAL; 61 } 62 return 0; 63 } 64 65 /** 66 * strlcpy - Copy a C-string into a sized buffer 67 * @dest: Where to copy the string to 68 * @src: Where to copy the string from 69 * @size: size of destination buffer 70 * 71 * Compatible with *BSD: the result is always a valid 72 * NUL-terminated string that fits in the buffer (unless, 73 * of course, the buffer size is zero). It does not pad 74 * out the result like strncpy() does. 75 * 76 * If libc has strlcpy() then that version will override this 77 * implementation: 78 */ 79 size_t __weak strlcpy(char *dest, const char *src, size_t size) 80 { 81 size_t ret = strlen(src); 82 83 if (size) { 84 size_t len = (ret >= size) ? size - 1 : ret; 85 memcpy(dest, src, len); 86 dest[len] = '\0'; 87 } 88 return ret; 89 } 90