/mexwrapper/strlcpy.c

/********************************************************************\



   Name:         strlcpy.c

   Created by:   Stefan Ritt



   Contents:     Contains strlcpy and strlcat which are versions of

                 strcpy and strcat, but which avoid buffer overflows



   $Id: strlcpy.c 16 2005-10-07 13:05:38Z ritt $



\********************************************************************/



#include <stdio.h>

#include <string.h>

#include "strlcpy.h"



/*

* Copy src to string dst of size siz.  At most siz-1 characters

* will be copied.  Always NUL terminates (unless size == 0).

* Returns strlen(src); if retval >= siz, truncation occurred.

*/

size_t strlcpy(char *dst, const char *src, size_t size)

{

   char *d = dst;

   const char *s = src;

   size_t n = size;



   /* Copy as many bytes as will fit */

   if (n != 0 && --n != 0) {

      do {

         if ((*d++ = *s++) == 0)

            break;

      } while (--n != 0);

   }



   /* Not enough room in dst, add NUL and traverse rest of src */

   if (n == 0) {

      if (size != 0)

         *d = '\0';             /* NUL-terminate dst */

      while (*s++);

   }



   return (s - src - 1);        /* count does not include NUL */

}



/*-------------------------------------------------------------------*/



/*

* Appends src to string dst of size siz (unlike strncat, siz is the

* full size of dst, not space left).  At most siz-1 characters

* will be copied.  Always NUL terminates (unless size <= strlen(dst)).

* Returns strlen(src) + MIN(size, strlen(initial dst)).

* If retval >= size, truncation occurred.

*/

size_t strlcat(char *dst, const char *src, size_t size)

{

   char *d = dst;

   const char *s = src;

   size_t n = size;

   size_t dlen;



   /* Find the end of dst and adjust bytes left but don't go past end */

   while (n-- != 0 && *d != '\0')

      d++;

   dlen = d - dst;

   n = size - dlen;



   if (n == 0)

      return (dlen + strlen(s));

   while (*s != '\0') {

      if (n != 1) {

         *d++ = *s;

         n--;

      }

      s++;

   }

   *d = '\0';



   return (dlen + (s - src));   /* count does not include NUL */

}



/*-------------------------------------------------------------------*/