diff options
Diffstat (limited to 'drivers/firmware/efi/libstub/string.c')
| -rw-r--r-- | drivers/firmware/efi/libstub/string.c | 204 |
1 files changed, 204 insertions, 0 deletions
diff --git a/drivers/firmware/efi/libstub/string.c b/drivers/firmware/efi/libstub/string.c new file mode 100644 index 0000000000..168fe8e79a --- /dev/null +++ b/drivers/firmware/efi/libstub/string.c @@ -0,0 +1,204 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Taken from: + * linux/lib/string.c + * + * Copyright (C) 1991, 1992 Linus Torvalds + */ + +#include <linux/ctype.h> +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/string.h> + +#ifndef EFI_HAVE_STRLEN +/** + * strlen - Find the length of a string + * @s: The string to be sized + */ +size_t strlen(const char *s) +{ + const char *sc; + + for (sc = s; *sc != '\0'; ++sc) + /* nothing */; + return sc - s; +} +#endif + +#ifndef EFI_HAVE_STRNLEN +/** + * strnlen - Find the length of a length-limited string + * @s: The string to be sized + * @count: The maximum number of bytes to search + */ +size_t strnlen(const char *s, size_t count) +{ + const char *sc; + + for (sc = s; count-- && *sc != '\0'; ++sc) + /* nothing */; + return sc - s; +} +#endif + +/** + * strstr - Find the first substring in a %NUL terminated string + * @s1: The string to be searched + * @s2: The string to search for + */ +char *strstr(const char *s1, const char *s2) +{ + size_t l1, l2; + + l2 = strlen(s2); + if (!l2) + return (char *)s1; + l1 = strlen(s1); + while (l1 >= l2) { + l1--; + if (!memcmp(s1, s2, l2)) + return (char *)s1; + s1++; + } + return NULL; +} + +#ifndef EFI_HAVE_STRCMP +/** + * strcmp - Compare two strings + * @cs: One string + * @ct: Another string + */ +int strcmp(const char *cs, const char *ct) +{ + unsigned char c1, c2; + + while (1) { + c1 = *cs++; + c2 = *ct++; + if (c1 != c2) + return c1 < c2 ? -1 : 1; + if (!c1) + break; + } + return 0; +} +#endif + +/** + * strncmp - Compare two length-limited strings + * @cs: One string + * @ct: Another string + * @count: The maximum number of bytes to compare + */ +int strncmp(const char *cs, const char *ct, size_t count) +{ + unsigned char c1, c2; + + while (count) { + c1 = *cs++; + c2 = *ct++; + if (c1 != c2) + return c1 < c2 ? -1 : 1; + if (!c1) + break; + count--; + } + return 0; +} + +/* Works only for digits and letters, but small and fast */ +#define TOLOWER(x) ((x) | 0x20) + +static unsigned int simple_guess_base(const char *cp) +{ + if (cp[0] == '0') { + if (TOLOWER(cp[1]) == 'x' && isxdigit(cp[2])) + return 16; + else + return 8; + } else { + return 10; + } +} + +/** + * simple_strtoull - convert a string to an unsigned long long + * @cp: The start of the string + * @endp: A pointer to the end of the parsed string will be placed here + * @base: The number base to use + */ + +unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) +{ + unsigned long long result = 0; + + if (!base) + base = simple_guess_base(cp); + + if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x') + cp += 2; + + while (isxdigit(*cp)) { + unsigned int value; + + value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10; + if (value >= base) + break; + result = result * base + value; + cp++; + } + if (endp) + *endp = (char *)cp; + + return result; +} + +long simple_strtol(const char *cp, char **endp, unsigned int base) +{ + if (*cp == '-') + return -simple_strtoull(cp + 1, endp, base); + + return simple_strtoull(cp, endp, base); +} + +#ifdef CONFIG_EFI_PARAMS_FROM_FDT +#ifndef EFI_HAVE_STRRCHR +/** + * strrchr - Find the last occurrence of a character in a string + * @s: The string to be searched + * @c: The character to search for + */ +char *strrchr(const char *s, int c) +{ + const char *last = NULL; + do { + if (*s == (char)c) + last = s; + } while (*s++); + return (char *)last; +} +#endif +#ifndef EFI_HAVE_MEMCHR +/** + * memchr - Find a character in an area of memory. + * @s: The memory area + * @c: The byte to search for + * @n: The size of the area. + * + * returns the address of the first occurrence of @c, or %NULL + * if @c is not found + */ +void *memchr(const void *s, int c, size_t n) +{ + const unsigned char *p = s; + while (n-- != 0) { + if ((unsigned char)c == *p++) { + return (void *)(p - 1); + } + } + return NULL; +} +#endif +#endif |