/* -*- linux-c -*- ------------------------------------------------------- * * *   Copyright (C) 1991, 1992 Linus Torvalds *   Copyright 2007 rPath, Inc. - All Rights Reserved * *   This file is part of the Linux kernel, and is made available under *   the terms of the GNU General Public License version 2. * * ----------------------------------------------------------------------- */ /* * Very basic string functions */ #include "boot.h" int strcmp(const char *str1, const char *str2){	const unsigned char *s1 = (const unsigned char *)str1;	const unsigned char *s2 = (const unsigned char *)str2;	int delta = 0; 	while (*s1 || *s2) {		delta = *s2 - *s1;		if (delta)			return delta;		s1++;		s2++;	}	return 0;} 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;} size_t strnlen(const char *s, size_t maxlen){	const char *es = s;	while (*es && maxlen) {		es++;		maxlen--;	} 	return (es - s);} unsigned int atou(const char *s){	unsigned int i = 0;	while (isdigit(*s))		i = i * 10 + (*s++ - '0');	return i;} /* 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;} /** * 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;} /** * 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;}