/*  $OpenBSD: pwcache.c,v 1.9 2005/08/08 08:05:34 espie Exp $ */

/*

 * Copyright (c) 1989, 1993

 *  The Regents of the University of California.  All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 3. Neither the name of the University nor the names of its contributors

 *    may be used to endorse or promote products derived from this software

 *    without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 */

/* OPENBSD ORIGINAL: lib/libc/gen/pwcache.c */

#include "includes.h"

#include <sys/types.h>

#include <grp.h>

#include <pwd.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#define NCACHE  64      /* power of 2 */

#define MASK  (NCACHE - 1)    /* bits to store with */

#ifndef HAVE_USER_FROM_UID

char *

user_from_uid(uid_t uid, int nouser)

{

  static struct ncache {

    uid_t uid;

    char  *name;

  } c_uid[NCACHE];

  static int pwopen;

  static char nbuf[15];   /* 32 bits == 10 digits */

  struct passwd *pw;

  struct ncache *cp;

  cp = c_uid + (uid & MASK);

  if (cp->uid != uid || cp->name == NULL) {

    if (pwopen == 0) {

#ifdef HAVE_SETPASSENT

      setpassent(1);

#endif

      pwopen = 1;

    }

    if ((pw = getpwuid(uid)) == NULL) {

      if (nouser)

        return (NULL);

      (void)snprintf(nbuf, sizeof(nbuf), "%lu", (u_long)uid);

    }

    cp->uid = uid;

    if (cp->name != NULL)

      free(cp->name);

    cp->name = strdup(pw ? pw->pw_name : nbuf);

  }

  return (cp->name);

}

#endif

#ifndef HAVE_GROUP_FROM_GID

char *

group_from_gid(gid_t gid, int nogroup)

{

  static struct ncache {

    gid_t gid;

    char  *name;

  } c_gid[NCACHE];

  static int gropen;

  static char nbuf[15];   /* 32 bits == 10 digits */

  struct group *gr;

  struct ncache *cp;

  cp = c_gid + (gid & MASK);

  if (cp->gid != gid || cp->name == NULL) {

    if (gropen == 0) {

#ifdef HAVE_SETGROUPENT

      setgroupent(1);

#endif

      gropen = 1;

    }

    if ((gr = getgrgid(gid)) == NULL) {

      if (nogroup)

        return (NULL);

      (void)snprintf(nbuf, sizeof(nbuf), "%lu", (u_long)gid);

    }

    cp->gid = gid;

    if (cp->name != NULL)

      free(cp->name);

    cp->name = strdup(gr ? gr->gr_name : nbuf);

  }

  return (cp->name);

}

#endif