Greg Kroah-Hartman | b244131 | 2017-11-01 15:07:57 +0100 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
Ard Biesheuvel | e8f3010 | 2015-10-08 20:02:04 +0100 | [diff] [blame] | 2 | /* |
| 3 | * Taken from: |
| 4 | * linux/lib/string.c |
| 5 | * |
| 6 | * Copyright (C) 1991, 1992 Linus Torvalds |
| 7 | */ |
| 8 | |
| 9 | #include <linux/types.h> |
| 10 | #include <linux/string.h> |
| 11 | |
| 12 | #ifndef __HAVE_ARCH_STRSTR |
| 13 | /** |
| 14 | * strstr - Find the first substring in a %NUL terminated string |
| 15 | * @s1: The string to be searched |
| 16 | * @s2: The string to search for |
| 17 | */ |
| 18 | char *strstr(const char *s1, const char *s2) |
| 19 | { |
| 20 | size_t l1, l2; |
| 21 | |
| 22 | l2 = strlen(s2); |
| 23 | if (!l2) |
| 24 | return (char *)s1; |
| 25 | l1 = strlen(s1); |
| 26 | while (l1 >= l2) { |
| 27 | l1--; |
| 28 | if (!memcmp(s1, s2, l2)) |
| 29 | return (char *)s1; |
| 30 | s1++; |
| 31 | } |
| 32 | return NULL; |
| 33 | } |
| 34 | #endif |
| 35 | |
| 36 | #ifndef __HAVE_ARCH_STRNCMP |
| 37 | /** |
| 38 | * strncmp - Compare two length-limited strings |
| 39 | * @cs: One string |
| 40 | * @ct: Another string |
| 41 | * @count: The maximum number of bytes to compare |
| 42 | */ |
| 43 | int strncmp(const char *cs, const char *ct, size_t count) |
| 44 | { |
| 45 | unsigned char c1, c2; |
| 46 | |
| 47 | while (count) { |
| 48 | c1 = *cs++; |
| 49 | c2 = *ct++; |
| 50 | if (c1 != c2) |
| 51 | return c1 < c2 ? -1 : 1; |
| 52 | if (!c1) |
| 53 | break; |
| 54 | count--; |
| 55 | } |
| 56 | return 0; |
| 57 | } |
| 58 | #endif |