reactos/modules/rosapps/applications/net/ncftp/Strn/Strnpcpy.c

55 lines
1.3 KiB
C

#include <sys/types.h>
#include <string.h>
#include "Strn.h"
/*
* Copy src to dst, truncating or null-padding to always copy n-1 bytes.
*
* This routine differs from strncpy in that it returns a pointer to the end
* of the buffer, instead of strncat which returns a pointer to the start.
*/
char *
Strnpcpy(char *const dst, const char *const src, size_t n)
{
register char *d;
register const char *s;
register char c;
char *ret;
register size_t i;
d = dst;
if (n != 0) {
s = src;
/* If they specified a maximum of n characters, use n - 1 chars to
* hold the copy, and the last character in the array as a NUL.
* This is the difference between the regular strncpy routine.
* strncpy doesn't guarantee that your new string will have a
* NUL terminator, but this routine does.
*/
for (i=1; i<n; i++) {
c = *s++;
if (c == '\0') {
ret = d; /* Return ptr to end byte. */
*d++ = c;
#if (STRNP_ZERO_PAD == 1)
/* Pad with zeros. */
for (; i<n; i++)
*d++ = 0;
#endif /* STRNP_ZERO_PAD */
return ret;
}
*d++ = c;
}
/* If we get here, then we have a full string, with n - 1 characters,
* so now we NUL terminate it and go home.
*/
*d = '\0';
return (d); /* Return ptr to end byte. */
} else {
*d = 0;
}
return (d); /* Return ptr to end byte. */
} /* Strnpcpy */
/* eof Strn.c */