/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * Copyright (C) 2012 - 2016 Red Hat, Inc.
 * Author: Matthias Clasen <mclasen@redhat.com>
 */

#include "src/core/nm-default-daemon.h"

#include "nm-power-monitor.h"

#include <sys/stat.h>
#include <gio/gunixfdlist.h>

#include "libnm-glib-aux/nm-dbus-aux.h"
#include "libnm-core-intern/nm-core-internal.h"
#include "NetworkManagerUtils.h"

#if defined(SUSPEND_RESUME_SYSTEMD) || defined(SUSPEND_RESUME_ELOGIND)

#define SUSPEND_DBUS_NAME      "org.freedesktop.login1"
#define SUSPEND_DBUS_PATH      "/org/freedesktop/login1"
#define SUSPEND_DBUS_INTERFACE "org.freedesktop.login1.Manager"
#if defined(SUSPEND_RESUME_SYSTEMD)
#define _NMLOG_PREFIX_NAME "power-monitor-sd"
#else
#define _NMLOG_PREFIX_NAME "power-monitor-el"
#endif

#elif defined(SUSPEND_RESUME_CONSOLEKIT)

/* ConsoleKit2 has added the same suspend/resume DBUS API that Systemd
 * uses. http://consolekit2.github.io/ConsoleKit2/#Manager.Inhibit
 */

#define SUSPEND_DBUS_NAME      "org.freedesktop.ConsoleKit"
#define SUSPEND_DBUS_PATH      "/org/freedesktop/ConsoleKit/Manager"
#define SUSPEND_DBUS_INTERFACE "org.freedesktop.ConsoleKit.Manager"
#define _NMLOG_PREFIX_NAME     "power-monitor-ck"

#else

#error define one of SUSPEND_RESUME_SYSTEMD, SUSPEND_RESUME_ELOGIND, SUSPEND_RESUME_CONSOLEKIT

#endif

/*****************************************************************************/

enum {
    SLEEPING,
    SHUTDOWN,
    LAST_SIGNAL,
};

static guint signals[LAST_SIGNAL] = {0};

struct _NMPowerMonitor {
    GObject parent;

    GDBusProxy *proxy;

    /* used both during construction of proxy and during Inhibit call. */
    GCancellable *cancellable;

    int     inhibit_fd;
    GSList *handles_active;
    GSList *handles_stale;

    gulong sig_id_1;
    gulong sig_id_2;
    gulong sig_id_3;
};

struct _NMPowerMonitorClass {
    GObjectClass parent;
};

G_DEFINE_TYPE(NMPowerMonitor, nm_power_monitor, G_TYPE_OBJECT);

/*****************************************************************************/

#define _NMLOG_DOMAIN      LOGD_SUSPEND
#define _NMLOG(level, ...) __NMLOG_DEFAULT(level, _NMLOG_DOMAIN, _NMLOG_PREFIX_NAME, __VA_ARGS__)

/*****************************************************************************/

static void
drop_inhibitor(NMPowerMonitor *self, gboolean force)
{
    if (!force && self->handles_active)
        return;

    if (self->inhibit_fd >= 0) {
        _LOGD("inhibit: dropping sleep inhibitor %d", self->inhibit_fd);
        nm_close(self->inhibit_fd);
        self->inhibit_fd = -1;
    }

    if (self->handles_active) {
        self->handles_stale  = g_slist_concat(self->handles_stale, self->handles_active);
        self->handles_active = NULL;
    }

    nm_clear_g_cancellable(&self->cancellable);
}

static void
inhibit_done(GObject *source, GAsyncResult *result, gpointer user_data)
{
    GDBusProxy                  *proxy   = G_DBUS_PROXY(source);
    NMPowerMonitor              *self    = user_data;
    gs_free_error GError        *error   = NULL;
    gs_unref_variant GVariant   *res     = NULL;
    gs_unref_object GUnixFDList *fd_list = NULL;

    res = g_dbus_proxy_call_with_unix_fd_list_finish(proxy, &fd_list, result, &error);
    if (!res) {
        if (!g_error_matches(error, G_IO_ERROR, G_IO_ERROR_CANCELLED)) {
            g_clear_object(&self->cancellable);
            _LOGW("inhibit: failed (%s)", error->message);
        }
        return;
    }

    g_clear_object(&self->cancellable);

    if (!fd_list || g_unix_fd_list_get_length(fd_list) != 1) {
        _LOGW("inhibit: didn't get a single fd back");
        return;
    }

    self->inhibit_fd = g_unix_fd_list_get(fd_list, 0, NULL);
    _LOGD("inhibit: inhibitor fd is %d", self->inhibit_fd);
}

static void
take_inhibitor(NMPowerMonitor *self)
{
    g_return_if_fail(NM_IS_POWER_MONITOR(self));
    g_return_if_fail(G_IS_DBUS_PROXY(self->proxy));

    drop_inhibitor(self, TRUE);

    _LOGD("inhibit: taking sleep inhibitor...");
    self->cancellable = g_cancellable_new();
    g_dbus_proxy_call_with_unix_fd_list(self->proxy,
                                        "Inhibit",
                                        g_variant_new("(ssss)",
                                                      "sleep",
                                                      "NetworkManager",
                                                      "NetworkManager needs to turn off networks",
                                                      "delay"),
                                        0,
                                        G_MAXINT,
                                        NULL,
                                        self->cancellable,
                                        inhibit_done,
                                        self);
}

static void
name_owner_cb(GObject *object, GParamSpec *pspec, gpointer user_data)
{
    GDBusProxy     *proxy = G_DBUS_PROXY(object);
    NMPowerMonitor *self  = NM_POWER_MONITOR(user_data);
    char           *owner;

    g_assert(proxy == self->proxy);

    owner = g_dbus_proxy_get_name_owner(proxy);
    if (owner)
        take_inhibitor(self);
    else
        drop_inhibitor(self, TRUE);
    g_free(owner);
}

static void
prepare_for_sleep_cb(GDBusProxy *proxy, gboolean is_about_to_suspend, NMPowerMonitor *self)
{
    g_return_if_fail(NM_IS_POWER_MONITOR(self));

    _LOGD("received %s signal", is_about_to_suspend ? "SLEEP" : "RESUME");

    if (!is_about_to_suspend)
        take_inhibitor(self);

    g_signal_emit(self, signals[SLEEPING], 0, is_about_to_suspend);

    if (is_about_to_suspend)
        drop_inhibitor(self, FALSE);
}

static void
prepare_for_shutdown_cb(GDBusProxy *proxy, gboolean is_about_to_shutdown, NMPowerMonitor *self)
{
    g_return_if_fail(NM_IS_POWER_MONITOR(self));

    _LOGD("received SHUTDOWN signal");

    g_signal_emit(self, signals[SHUTDOWN], 0);
}

/**
 * nm_power_monitor_inhibit_take:
 * @self: the #NMPowerMonitor instance
 *
 * Prevent the release of inhibitor lock
 *
 * Returns: an inhibitor handle that must be returned via
 *   nm_power_monitor_inhibit_release().
 **/
NMPowerMonitorInhibitorHandle *
nm_power_monitor_inhibit_take(NMPowerMonitor *self)
{
    g_return_val_if_fail(NM_IS_POWER_MONITOR(self), NULL);

    self->handles_active = g_slist_prepend(self->handles_active, NULL);
    return (NMPowerMonitorInhibitorHandle *) self->handles_active;
}

/**
 * nm_power_monitor_inhibit_release:
 * @self: the #NMPowerMonitor instance
 * @handle: the #NMPowerMonitorInhibitorHandle inhibitor handle.
 *
 * Allow again the release of inhibitor lock
 **/
void
nm_power_monitor_inhibit_release(NMPowerMonitor *self, NMPowerMonitorInhibitorHandle *handle)
{
    GSList *l;

    g_return_if_fail(NM_IS_POWER_MONITOR(self));
    g_return_if_fail(handle);

    l = (GSList *) handle;

    if (g_slist_position(self->handles_active, l) < 0) {
        if (g_slist_position(self->handles_stale, l) < 0)
            g_return_if_reached();
        self->handles_stale = g_slist_delete_link(self->handles_stale, l);
        return;
    }

    self->handles_active = g_slist_delete_link(self->handles_active, l);

    drop_inhibitor(self, FALSE);
}

static void
on_proxy_acquired(GObject *object, GAsyncResult *res, NMPowerMonitor *self)
{
    GError     *error = NULL;
    GDBusProxy *proxy;

    proxy = g_dbus_proxy_new_for_bus_finish(res, &error);
    if (!proxy) {
        if (!g_error_matches(error, G_IO_ERROR, G_IO_ERROR_CANCELLED))
            _LOGW("failed to acquire D-Bus proxy: %s", error->message);
        g_clear_error(&error);
        return;
    }
    self->proxy = proxy;
    g_clear_object(&self->cancellable);

    self->sig_id_1 =
        g_signal_connect(self->proxy, "notify::g-name-owner", G_CALLBACK(name_owner_cb), self);
    self->sig_id_2 = _nm_dbus_proxy_signal_connect(self->proxy,
                                                   "PrepareForSleep",
                                                   G_VARIANT_TYPE("(b)"),
                                                   G_CALLBACK(prepare_for_sleep_cb),
                                                   self);
    self->sig_id_3 = _nm_dbus_proxy_signal_connect(self->proxy,
                                                   "PrepareForShutdown",
                                                   G_VARIANT_TYPE("(b)"),
                                                   G_CALLBACK(prepare_for_shutdown_cb),
                                                   self);

    {
        gs_free char *owner = NULL;

        owner = g_dbus_proxy_get_name_owner(self->proxy);
        if (owner)
            take_inhibitor(self);
    }
}

/*****************************************************************************/

static void
nm_power_monitor_init(NMPowerMonitor *self)
{
    self->inhibit_fd  = -1;
    self->cancellable = g_cancellable_new();
    g_dbus_proxy_new_for_bus(G_BUS_TYPE_SYSTEM,
                             G_DBUS_PROXY_FLAGS_DO_NOT_AUTO_START
                                 | G_DBUS_PROXY_FLAGS_DO_NOT_LOAD_PROPERTIES,
                             NULL,
                             SUSPEND_DBUS_NAME,
                             SUSPEND_DBUS_PATH,
                             SUSPEND_DBUS_INTERFACE,
                             self->cancellable,
                             (GAsyncReadyCallback) on_proxy_acquired,
                             self);
}

NMPowerMonitor *
nm_power_monitor_new(void)
{
    return g_object_new(NM_TYPE_POWER_MONITOR, NULL);
}

static void
dispose(GObject *object)
{
    NMPowerMonitor *self = NM_POWER_MONITOR(object);

    drop_inhibitor(self, TRUE);

    nm_clear_g_cancellable(&self->cancellable);

    if (self->proxy) {
        nm_clear_g_signal_handler(self->proxy, &self->sig_id_1);
        nm_clear_g_signal_handler(self->proxy, &self->sig_id_2);
        nm_clear_g_signal_handler(self->proxy, &self->sig_id_3);
        g_clear_object(&self->proxy);
    }

    G_OBJECT_CLASS(nm_power_monitor_parent_class)->dispose(object);
}

static void
nm_power_monitor_class_init(NMPowerMonitorClass *klass)
{
    GObjectClass *gobject_class;

    gobject_class = G_OBJECT_CLASS(klass);

    gobject_class->dispose = dispose;

    signals[SLEEPING] = g_signal_new(NM_POWER_MONITOR_SLEEPING,
                                     NM_TYPE_POWER_MONITOR,
                                     G_SIGNAL_RUN_LAST,
                                     0,
                                     NULL,
                                     NULL,
                                     g_cclosure_marshal_VOID__BOOLEAN,
                                     G_TYPE_NONE,
                                     1,
                                     G_TYPE_BOOLEAN);
    signals[SHUTDOWN] = g_signal_new(NM_POWER_MONITOR_SHUTDOWN,
                                     NM_TYPE_POWER_MONITOR,
                                     G_SIGNAL_RUN_LAST,
                                     0,
                                     NULL,
                                     NULL,
                                     NULL,
                                     G_TYPE_NONE,
                                     0);
}