freebsd-skq/sys/boot/common/util.c
avg 47b0933c6d strncmp for boot code: fix an off by one error
Before this change strncmp would access and _compare_ n+1 characters
in the case where the first n characters match.

MFC after:	5 days
2013-04-05 09:14:30 +00:00

177 lines
2.9 KiB
C

/*-
* Copyright (c) 1998 Robert Nordier
* Copyright (c) 2010 Pawel Jakub Dawidek <pjd@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms are freely
* permitted provided that the above copyright notice and this
* paragraph and the following disclaimer are duplicated in all
* such forms.
*
* This software is provided "AS IS" and without any express or
* implied warranties, including, without limitation, the implied
* warranties of merchantability and fitness for a particular
* purpose.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <stdarg.h>
#include "cons.h"
#include "util.h"
void
memcpy(void *dst, const void *src, int len)
{
const char *s = src;
char *d = dst;
while (len--)
*d++ = *s++;
}
void
memset(void *b, int c, size_t len)
{
char *bp = b;
while (len--)
*bp++ = (unsigned char)c;
}
int
memcmp(const void *b1, const void *b2, size_t len)
{
const unsigned char *p1, *p2;
for (p1 = b1, p2 = b2; len > 0; len--, p1++, p2++) {
if (*p1 != *p2)
return ((*p1) - (*p2));
}
return (0);
}
int
strcmp(const char *s1, const char *s2)
{
for (; *s1 == *s2 && *s1 != '\0'; s1++, s2++)
;
return ((unsigned char)*s1 - (unsigned char)*s2);
}
int
strncmp(const char *s1, const char *s2, size_t len)
{
for (; len > 0 && *s1 == *s2 && *s1 != '\0'; len--, s1++, s2++)
;
return (len == 0 ? 0 : (unsigned char)*s1 - (unsigned char)*s2);
}
void
strcpy(char *dst, const char *src)
{
while (*src != '\0')
*dst++ = *src++;
*dst = '\0';
}
void
strcat(char *dst, const char *src)
{
while (*dst != '\0')
dst++;
while (*src != '\0')
*dst++ = *src++;
*dst = '\0';
}
char *
strchr(const char *s, char ch)
{
for (; *s != '\0'; s++) {
if (*s == ch)
return ((char *)(uintptr_t)(const void *)s);
}
return (NULL);
}
size_t
strlen(const char *s)
{
size_t len = 0;
while (*s++ != '\0')
len++;
return (len);
}
void
printf(const char *fmt, ...)
{
va_list ap;
const char *hex = "0123456789abcdef";
char buf[32], *s;
unsigned long long u;
int c, l;
va_start(ap, fmt);
while ((c = *fmt++) != '\0') {
if (c != '%') {
putchar(c);
continue;
}
l = 0;
nextfmt:
c = *fmt++;
switch (c) {
case 'l':
l++;
goto nextfmt;
case 'c':
putchar(va_arg(ap, int));
break;
case 's':
for (s = va_arg(ap, char *); *s != '\0'; s++)
putchar(*s);
break;
case 'd': /* A lie, always prints unsigned */
case 'u':
case 'x':
switch (l) {
case 2:
u = va_arg(ap, unsigned long long);
break;
case 1:
u = va_arg(ap, unsigned long);
break;
default:
u = va_arg(ap, unsigned int);
break;
}
s = buf;
if (c == 'd' || c == 'u') {
do
*s++ = '0' + (u % 10U);
while (u /= 10);
} else {
do
*s++ = hex[u & 0xfu];
while (u >>= 4);
}
while (--s >= buf)
putchar(*s);
break;
}
}
va_end(ap);
}