addons/network-devices/cache.c

/*
 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 *
 * Licensed under the Academic Free License version 2.1
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>

#include <libhal.h>
#include <logger.h>

#include <glib.h>

#include "network-discovery.h"

/*
 * The interfaces in this file comprise a means of keeping track of devices
 * that we have already seen and those that have gone missing.  This allows
 * us to quickly determine if we need to probe the device and quickly search
 * for devices that are no longer available.
 */

typedef struct {
    LibHalContext *ctx;
    time_t timestamp;
} removal_args_t;

static GHashTable *seen = NULL;

static gboolean
device_remove_if_stale(gpointer key, gpointer value, gpointer user_data)
{
    gboolean result = FALSE;
    removal_args_t *args = user_data;
    char *name = key;
    time_t *val = value;

    HAL_DEBUG(("test stale: %s (%d > %d)", name, args->timestamp, *val));
    if (args->timestamp > *val) {
        DBusError error;
        char **udi = NULL;
        int num = 0;

        dbus_error_init(&error);
        udi = libhal_manager_find_device_string_match(args->ctx,
                    "network_device.address", name,
                    &num, &error);

        if (udi != NULL) {
            int i;

            for (i = 0; i < num; i++) {
                libhal_remove_device(args->ctx, udi[i], &error);
                HAL_DEBUG(("remove: %s (%s)", name, udi[i]));
            }
            libhal_free_string_array(udi);
            result = TRUE;
        }
        if (dbus_error_is_set(&error))
            dbus_error_free(&error);
    }

    return (result);
}

void
scan_for_stale_devices(LibHalContext *ctx, time_t timestamp)
{
    if (seen != NULL) {
        removal_args_t args[1];

        args->ctx = ctx;
        args->timestamp = timestamp;

        g_hash_table_foreach_remove(seen, device_remove_if_stale, args);
    }
}

gboolean
device_seen(char *name)
{
    gboolean result;
    char *key;
    time_t *val;

    if (seen == NULL)
        seen = g_hash_table_new_full(g_str_hash, g_str_equal,
                        free, free);

    result = g_hash_table_lookup_extended(seen, name,
                (gpointer)&key, (gpointer)&val);

    if ((result == FALSE) && ((val = calloc(1, sizeof (*val))) != NULL)) {
        g_hash_table_insert(seen, strdup(name), val);
    }
    (void) time(val);
    HAL_DEBUG(("seen: %s (%d)", name, *val));

    return (result);
}