matos/core/klibc.c
2018-11-20 17:03:57 +01:00

90 lines
1.8 KiB
C

#include "klibc.h"
void *memcpy(void *dst, const void *src, size_t n)
{
char *dstChar = dst;
const char *srcChar = src;
for (size_t i = 0; i < n; i++) {
*(dstChar++) = *(srcChar++);
}
return dst;
}
void *memset(void *src, int c, size_t n)
{
for (char *ptr = (char *)src; n > 0; n--, ptr++) {
*ptr = (char)c;
}
return src;
}
char * itoa( int value, char * str, int base )
{
char * rc;
char * ptr;
char * low;
// Check for supported base.
if ( base < 2 || base > 36 )
{
*str = '\0';
return str;
}
rc = ptr = str;
// Set '-' for negative decimals.
if ( value < 0 && base == 10 )
{
*ptr++ = '-';
}
// Remember where the numbers start.
low = ptr;
// The actual conversion.
do
{
// Modulo is negative for negative value. This trick makes abs() unnecessary.
*ptr++ = "zyxwvutsrqponmlkjihgfedcba9876543210123456789abcdefghijklmnopqrstuvwxyz"[35 + value % base];
value /= base;
} while ( value );
// Terminating the string.
*ptr-- = '\0';
// Invert the numbers.
while ( low < ptr )
{
char tmp = *low;
*low++ = *ptr;
*ptr-- = tmp;
}
return rc;
}
/* K&R */
void reverse(char s[])
{
int c, i, j;
for (i = 0, j = strlen(s) - 1; i < j; i++, j--) {
c = s[i];
s[i] = s[j];
s[j] = c;
}
}
/* K&R */
int strlen(char s[])
{
int i = 0;
while (s[i] != '\0')
++i;
return i;
}
/* K&R
* Returns <0 if s1<s2, 0 if s1==s2, >0 if s1>s2 */
int strcmp(char s1[], char s2[])
{
int i;
for (i = 0; s1[i] == s2[i]; i++) {
if (s1[i] == '\0')
return 0;
}
return s1[i] - s2[i];
}