utils.c

来自「Compex BIOS for SAMSUNG S3C4510B v1.20-l」· C语言 代码 · 共 107 行

#include "utils.h"

int strncmp(const char *cs, const char *ct, size_t count)
{
	register signed char __res = 0;

	while (count) {
		if ((__res = *cs - *ct++) != 0 || !*cs++)
			break;
		count--;
	}

	return __res;
}

void * memcpy(void *dest, const void *src, size_t count)
{
	char *tmp = (char *)dest, *s = (char *)src;
	
	while (count--)
		*tmp++ = *s++;

	return dest;
}

void * memset(void *s, int c, size_t count)
{
	char *xs = (char *)s;

	while (count--)
		*xs++ = c;

	return s;
}

void * memmove(void *dest, const void *src, size_t count)
{
	char *tmp, *s;

	if (dest <= src) {
		tmp = (char *)dest;
		s = (char *)src;
		while (count--)
			*tmp++ = *s++;
	} else {
		tmp = (char *)dest + count;
		s = (char *)src + count;
		while (count--)
			*--tmp = *--s;
	}

	return dest;
}

unsigned short ntohs(unsigned short s)
{
	return (s >> 8) | (s << 8);
}

unsigned long ntohl(unsigned long l)
{
	return  ((l >> 24) & 0x000000ff) |
		((l >>  8) & 0x0000ff00) |
		((l <<  8) & 0x00ff0000) |
		((l << 24) & 0xff000000);
}

unsigned short htons(unsigned short s)
{
	return (s >> 8) | (s << 8);
}

unsigned long htonl(unsigned long l)
{
	return  ((l >> 24) & 0x000000ff) |
		((l >>  8) & 0x0000ff00) |
		((l <<  8) & 0x00ff0000) |
		((l << 24) & 0xff000000);
}

unsigned long strtoul(char *s, char **endptr, int radix)
{
	unsigned long ret;
	int i;

	ret = 0;

	while (*s != '\0') {
		if (*s >= '0' && *s <= '9')
			i = *s - '0';
		else if (*s >= 'a' && *s <= 'f')
			i = *s - 'a' + 0xa;
		else if (*s >= 'A' && *s <= 'F')
			i = *s - 'A' + 0xa;
		else
			break;

		if (i >= radix)
			break;

		ret = (ret * radix) + i;
		s++;
	}

	return ret;
}