usr/klibc/memmove.c

/*
 * memmove.c
 */

#include <string.h>

void *memmove(void *dst, const void *src, size_t n)
{
	const char *p = src;
	char *q = dst;
#if defined(__i386__) || defined(__x86_64__)
	if (q < p) {
		asm volatile("cld; rep; movsb"
			     : "+c" (n), "+S"(p), "+D"(q));
	} else {
		p += (n - 1);
		q += (n - 1);
		asm volatile("std; rep; movsb; cld"
			     : "+c" (n), "+S"(p), "+D"(q));
	}
#else
	if (q < p) {
		while (n--) {
			*q++ = *p++;
		}
	} else {
		p += n;
		q += n;
		while (n--) {
			*--q = *--p;
		}
	}
#endif

	return dst;
}
1	niro	532	/*
2			* memmove.c
3			*/
4
5			#include <string.h>
6
7			void memmove(void dst, const void *src, size_t n)
8			{
9			const char *p = src;
10			char *q = dst;
11			#if defined(__i386__) \|\| defined(__x86_64__)
12			if (q < p) {
13	niro	815	asm volatile("cld; rep; movsb"
14	niro	532	: "+c" (n), "+S"(p), "+D"(q));
15			} else {
16			p += (n - 1);
17			q += (n - 1);
18	niro	815	asm volatile("std; rep; movsb; cld"
19	niro	532	: "+c" (n), "+S"(p), "+D"(q));
20			}
21			#else
22			if (q < p) {
23			while (n--) {
24			q++ = p++;
25			}
26			} else {
27			p += n;
28			q += n;
29			while (n--) {
30			--q = --p;
31			}
32			}
33			#endif
34
35			return dst;
36			}