busybox

/* vi: set sw=4 ts=4: */

/*

 * Utility routines.

 *

 * Copyright 1998 by Albert Cahalan; all rights reserved.

 * Copyright (C) 2002 by Vladimir Oleynik <dzo@simtreas.ru>

 * SELinux support: (c) 2007 by Yuichi Nakamura <ynakam@hitachisoft.jp>

 *

 * Licensed under GPLv2 or later, see file LICENSE in this source tree.

 */

​

#include "libbb.h"

​

​

typedef struct id_to_name_map_t {

    uid_t id;

    char name[USERNAME_MAX_SIZE];

} id_to_name_map_t;

​

typedef struct cache_t {

    id_to_name_map_t *cache;

    int size;

} cache_t;

​

static cache_t username, groupname;

​

static void clear_cache(cache_t *cp)

{

    free(cp->cache);

    cp->cache = NULL;

    cp->size = 0;

}

void FAST_FUNC clear_username_cache(void)

{

    clear_cache(&username);

    clear_cache(&groupname);

}

​

#if 0 /* more generic, but we don't need that yet */

/* Returns -N-1 if not found. */

/* cp->cache[N] is allocated and must be filled in this case */

static int get_cached(cache_t *cp, uid_t id)

{

    int i;

    for (i = 0; i < cp->size; i++)

        if (cp->cache[i].id == id)

            return i;

    i = cp->size++;

    cp->cache = xrealloc_vector(cp->cache, 2, i);

    cp->cache[i++].id = id;

    return -i;

}

#endif

​

static char* get_cached(cache_t *cp, uid_t id,

            char* FAST_FUNC x2x_utoa(uid_t id))

{

    int i;

    for (i = 0; i < cp->size; i++)

        if (cp->cache[i].id == id)

            return cp->cache[i].name;

    i = cp->size++;

    cp->cache = xrealloc_vector(cp->cache, 2, i);