LeOS-Genesis/external/badvpn/flowextra/PacketPassInactivityMonitor.h

125 lines
4.7 KiB
C

/**
* @file PacketPassInactivityMonitor.h
* @author Ambroz Bizjak <ambrop7@gmail.com>
*
* @section LICENSE
*
* 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 author 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 COPYRIGHT HOLDERS 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 AUTHOR 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.
*
* @section DESCRIPTION
*
* A {@link PacketPassInterface} layer for detecting inactivity.
*/
#ifndef BADVPN_PACKETPASSINACTIVITYMONITOR_H
#define BADVPN_PACKETPASSINACTIVITYMONITOR_H
#include <base/DebugObject.h>
#include <system/BReactor.h>
#include <flow/PacketPassInterface.h>
/**
* Handler function invoked when inactivity is detected.
* It is guaranteed that the interfaces are in not sending state.
*
* @param user value given to {@link PacketPassInactivityMonitor_Init}
*/
typedef void (*PacketPassInactivityMonitor_handler) (void *user);
/**
* A {@link PacketPassInterface} layer for detecting inactivity.
* It reports inactivity to a user provided handler function.
*
* The object behaves like that:
* ("timer set" means started with the given timeout whether if was running or not,
* "timer unset" means stopped if it was running)
* - There is a timer.
* - The timer is set when the object is initialized.
* - When the input calls Send, the call is passed on to the output.
* If the output accepted the packet, the timer is set. If the output
* blocked the packet, the timer is unset.
* - When the output calls Done, the timer is set, and the call is
* passed on to the input.
* - When the input calls Cancel, the timer is set, and the call is
* passed on to the output.
* - When the timer expires, the timer is set, ant the user's handler
* function is invoked.
*/
typedef struct {
DebugObject d_obj;
PacketPassInterface *output;
BReactor *reactor;
PacketPassInactivityMonitor_handler handler;
void *user;
PacketPassInterface input;
BTimer timer;
} PacketPassInactivityMonitor;
/**
* Initializes the object.
* See {@link PacketPassInactivityMonitor} for details.
*
* @param o the object
* @param output output interface
* @param reactor reactor we live in
* @param interval timer value in milliseconds
* @param handler handler function for reporting inactivity, or NULL to disable
* @param user value passed to handler functions
*/
void PacketPassInactivityMonitor_Init (PacketPassInactivityMonitor *o, PacketPassInterface *output, BReactor *reactor, btime_t interval, PacketPassInactivityMonitor_handler handler, void *user);
/**
* Frees the object.
*
* @param o the object
*/
void PacketPassInactivityMonitor_Free (PacketPassInactivityMonitor *o);
/**
* Returns the input interface.
* The MTU of the interface will be the same as of the output interface.
* The interface supports cancel functionality if the output interface supports it.
*
* @param o the object
* @return input interface
*/
PacketPassInterface * PacketPassInactivityMonitor_GetInput (PacketPassInactivityMonitor *o);
/**
* Sets or removes the inactivity handler.
*
* @param o the object
* @param handler handler function for reporting inactivity, or NULL to disable
* @param user value passed to handler functions
*/
void PacketPassInactivityMonitor_SetHandler (PacketPassInactivityMonitor *o, PacketPassInactivityMonitor_handler handler, void *user);
/**
* Sets the timer to expire immediately in order to force an inactivity report.
*
* @param o the object
*/
void PacketPassInactivityMonitor_Force (PacketPassInactivityMonitor *o);
#endif