// SPDX-License-Identifier: GPL-2.0 /* * Taken from: * linux/lib/string.c * * Copyright (C) 1991, 1992 Linus Torvalds */ #include #include #include #include #ifndef __HAVE_ARCH_STRSTR /** * 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; } #endif #ifndef __HAVE_ARCH_STRNCMP /** * 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; } #endif /* 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); }