kernel/stdlib.c


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#include "stdlib.h"

void *memset(void *s, int c, size_t n)
{
    char *p = (char *) s;

    for (size_t i = 0; i < n; i++, p++)
        *p = (char) c;

    return s;
}

/* overlap is not handled */
void *memcpy(void *dest, void *src, size_t n)
{
    char *s = (char *) src;
    char *d = (char *) dest;

    for (size_t i = 0; i < n; i++, s++, d++)
        *d = *s;

    return dest;
}

int strncmp(const char *s1, const char *s2, size_t n)
{
    for (size_t i = 0; i < n; i++, s1++, s2++) {
        if (*s1 < *s2) return -1;
        if (*s1 > *s2) return 1;
    }

    return 0;
}