#include <u.h>#include <libc.h>#include "String.h"  /* return a String containing a copy of the passed char array */extern String*s_copy(char *cp){	String *sp;	int len; 	len = strlen(cp)+1;	sp = s_newalloc(len);	setmalloctag(sp, getcallerpc(&cp));	strcpy(sp->base, cp);	sp->ptr = sp->base + len - 1;		/* point to 0 terminator */	return sp;}