| /* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */ |
| /* dbus-resources.c Resource tracking/limits |
| * |
| * Copyright (C) 2003 Red Hat Inc. |
| * |
| * Licensed under the Academic Free License version 2.1 |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| * |
| */ |
| |
| #include <config.h> |
| #include <dbus/dbus-resources.h> |
| #include <dbus/dbus-internals.h> |
| |
| /** |
| * @defgroup DBusResources Resource limits related code |
| * @ingroup DBusInternals |
| * @brief DBusCounter and other stuff related to resource limits |
| * |
| * Types and functions related to tracking resource limits, |
| * such as the maximum amount of memory/unix fds a connection can use |
| * for messages, etc. |
| */ |
| |
| /** |
| * @defgroup DBusResourcesInternals Resource limits implementation details |
| * @ingroup DBusInternals |
| * @brief Resource limits implementation details |
| * |
| * Implementation details of resource limits code. |
| * |
| * @{ |
| */ |
| |
| /** |
| * @brief Internals of DBusCounter. |
| * |
| * DBusCounter internals. DBusCounter is an opaque object, it must be |
| * used via accessor functions. |
| */ |
| struct DBusCounter |
| { |
| int refcount; /**< reference count */ |
| |
| long size_value; /**< current size counter value */ |
| long unix_fd_value; /**< current unix fd counter value */ |
| |
| #ifdef DBUS_ENABLE_STATS |
| long peak_size_value; /**< largest ever size counter value */ |
| long peak_unix_fd_value; /**< largest ever unix fd counter value */ |
| #endif |
| |
| long notify_size_guard_value; /**< call notify function when crossing this size value */ |
| long notify_unix_fd_guard_value; /**< call notify function when crossing this unix fd value */ |
| |
| DBusCounterNotifyFunction notify_function; /**< notify function */ |
| void *notify_data; /**< data for notify function */ |
| dbus_bool_t notify_pending : 1; /**< TRUE if the guard value has been crossed */ |
| }; |
| |
| /** @} */ /* end of resource limits internals docs */ |
| |
| /** |
| * @addtogroup DBusResources |
| * @{ |
| */ |
| |
| /** |
| * Creates a new DBusCounter. DBusCounter is used |
| * to count usage of some resource such as memory. |
| * |
| * @returns new counter or #NULL on failure |
| */ |
| DBusCounter* |
| _dbus_counter_new (void) |
| { |
| DBusCounter *counter; |
| |
| counter = dbus_new0 (DBusCounter, 1); |
| if (counter == NULL) |
| return NULL; |
| |
| counter->refcount = 1; |
| |
| return counter; |
| } |
| |
| /** |
| * Increments refcount of the counter |
| * |
| * @param counter the counter |
| * @returns the counter |
| */ |
| DBusCounter * |
| _dbus_counter_ref (DBusCounter *counter) |
| { |
| _dbus_assert (counter->refcount > 0); |
| |
| counter->refcount += 1; |
| |
| return counter; |
| } |
| |
| /** |
| * Decrements refcount of the counter and possibly |
| * finalizes the counter. |
| * |
| * @param counter the counter |
| */ |
| void |
| _dbus_counter_unref (DBusCounter *counter) |
| { |
| _dbus_assert (counter->refcount > 0); |
| |
| counter->refcount -= 1; |
| |
| if (counter->refcount == 0) |
| { |
| |
| dbus_free (counter); |
| } |
| } |
| |
| /** |
| * Adjusts the value of the size counter by the given |
| * delta which may be positive or negative. |
| * |
| * This function may be called with locks held. After calling it, when |
| * any relevant locks are no longer held you must call _dbus_counter_notify(). |
| * |
| * @param counter the counter |
| * @param delta value to add to the size counter's current value |
| */ |
| void |
| _dbus_counter_adjust_size (DBusCounter *counter, |
| long delta) |
| { |
| long old = counter->size_value; |
| |
| counter->size_value += delta; |
| |
| #ifdef DBUS_ENABLE_STATS |
| if (counter->peak_size_value < counter->size_value) |
| counter->peak_size_value = counter->size_value; |
| #endif |
| |
| #if 0 |
| _dbus_verbose ("Adjusting counter %ld by %ld = %ld\n", |
| old, delta, counter->size_value); |
| #endif |
| |
| if (counter->notify_function != NULL && |
| ((old < counter->notify_size_guard_value && |
| counter->size_value >= counter->notify_size_guard_value) || |
| (old >= counter->notify_size_guard_value && |
| counter->size_value < counter->notify_size_guard_value))) |
| counter->notify_pending = TRUE; |
| } |
| |
| /** |
| * Calls the notify function from _dbus_counter_set_notify(), |
| * if that function has been specified and the counter has crossed the |
| * guard value (in either direction) since the last call to this function. |
| * |
| * This function must not be called with locks held, since it can call out |
| * to user code. |
| */ |
| void |
| _dbus_counter_notify (DBusCounter *counter) |
| { |
| if (counter->notify_pending) |
| { |
| counter->notify_pending = FALSE; |
| (* counter->notify_function) (counter, counter->notify_data); |
| } |
| } |
| |
| /** |
| * Adjusts the value of the unix fd counter by the given |
| * delta which may be positive or negative. |
| * |
| * This function may be called with locks held. After calling it, when |
| * any relevant locks are no longer held you must call _dbus_counter_notify(). |
| * |
| * @param counter the counter |
| * @param delta value to add to the unix fds counter's current value |
| */ |
| void |
| _dbus_counter_adjust_unix_fd (DBusCounter *counter, |
| long delta) |
| { |
| long old = counter->unix_fd_value; |
| |
| counter->unix_fd_value += delta; |
| |
| #ifdef DBUS_ENABLE_STATS |
| if (counter->peak_unix_fd_value < counter->unix_fd_value) |
| counter->peak_unix_fd_value = counter->unix_fd_value; |
| #endif |
| |
| #if 0 |
| _dbus_verbose ("Adjusting counter %ld by %ld = %ld\n", |
| old, delta, counter->unix_fd_value); |
| #endif |
| |
| if (counter->notify_function != NULL && |
| ((old < counter->notify_unix_fd_guard_value && |
| counter->unix_fd_value >= counter->notify_unix_fd_guard_value) || |
| (old >= counter->notify_unix_fd_guard_value && |
| counter->unix_fd_value < counter->notify_unix_fd_guard_value))) |
| counter->notify_pending = TRUE; |
| } |
| |
| /** |
| * Gets the current value of the size counter. |
| * |
| * @param counter the counter |
| * @returns its current size value |
| */ |
| long |
| _dbus_counter_get_size_value (DBusCounter *counter) |
| { |
| return counter->size_value; |
| } |
| |
| /** |
| * Gets the current value of the unix fd counter. |
| * |
| * @param counter the counter |
| * @returns its current unix fd value |
| */ |
| long |
| _dbus_counter_get_unix_fd_value (DBusCounter *counter) |
| { |
| return counter->unix_fd_value; |
| } |
| |
| /** |
| * Sets the notify function for this counter; the notify function is |
| * called whenever the counter's values cross the guard values in |
| * either direction (moving up, or moving down). |
| * |
| * @param counter the counter |
| * @param size_guard_value the value we're notified if the size counter crosses |
| * @param unix_fd_guard_value the value we're notified if the unix fd counter crosses |
| * @param function function to call in order to notify |
| * @param user_data data to pass to the function |
| */ |
| void |
| _dbus_counter_set_notify (DBusCounter *counter, |
| long size_guard_value, |
| long unix_fd_guard_value, |
| DBusCounterNotifyFunction function, |
| void *user_data) |
| { |
| counter->notify_size_guard_value = size_guard_value; |
| counter->notify_unix_fd_guard_value = unix_fd_guard_value; |
| counter->notify_function = function; |
| counter->notify_data = user_data; |
| counter->notify_pending = FALSE; |
| } |
| |
| #ifdef DBUS_ENABLE_STATS |
| long |
| _dbus_counter_get_peak_size_value (DBusCounter *counter) |
| { |
| return counter->peak_size_value; |
| } |
| |
| long |
| _dbus_counter_get_peak_unix_fd_value (DBusCounter *counter) |
| { |
| return counter->peak_unix_fd_value; |
| } |
| #endif |
| |
| /** @} */ /* end of resource limits exported API */ |