/* $Header: /afs/sipb.mit.edu/project/sipb-athena/repository/src/moira/lib/kname_unparse.c,v 1.1 1996/06/02 07:44:11 ghudson Exp $
 *
 * Don't know why this function is not in libkrb.a.  It's the inverse
 * of kname_parse() which is there.
 */

#include <stdio.h>
#include <des.h>
#include <krb.h>

/* Turn a principal, instance, realm triple into a single non-ambiguous 
 * string.  This is the inverse of kname_parse().  It returns a pointer
 * to a static buffer, or NULL on error.
 */

char *kname_unparse(p, i, r)
char *p;
char *i;
char *r;
{
    static char name[MAX_K_NAME_SZ];
    char *s;

    s = name;
    if (!p || strlen(p) > ANAME_SZ)
      return(NULL);
    while (*p) {
	switch (*p) {
	case '@':
	    *s++ = '\\';
	    *s++ = '@';
	    break;
	case '.':
	    *s++ = '\\';
	    *s++ = '.';
	    break;
	case '\\':
	    *s++ = '\\';
	    *s++ = '\\';
	    break;
	default:
	    *s++ = *p;
	}
	p++;
    }
    if (i && *i) {
	if (strlen(i) > INST_SZ)
	  return(NULL);
	*s++ = '.';
	while (*i) {
	    switch (*i) {
	    case '@':
		*s++ = '\\';
		*s++ = '@';
		break;
	    case '.':
		*s++ = '\\';
		*s++ = '.';
		break;
	    case '\\':
		*s++ = '\\';
		*s++ = '\\';
		break;
	    default:
		*s++ = *i;
	    }
	    i++;
	}
    }
    *s++ = '@';
    if (!r || strlen(r) > REALM_SZ)
      return(NULL);
    while (*r) {
	switch (*r) {
	case '@':
	    *s++ = '\\';
	    *s++ = '@';
	    break;
	case '\\':
	    *s++ = '\\';
	    *s++ = '\\';
	    break;
	default:
	    *s++ = *r;
	}
	r++;
    }
    *s = '\0';
    return(&name[0]);
}