badvpn/flow/PacketRecvBlocker.h
2012-01-27 13:24:37 +00:00

91 lines
3.1 KiB
C

/**
* @file PacketRecvBlocker.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
*
* {@link PacketRecvInterface} layer which blocks all output recv calls and only
* passes a single blocked call on to input when the user wants so.
*/
#ifndef BADVPN_FLOW_PACKETRECVBLOCKER_H
#define BADVPN_FLOW_PACKETRECVBLOCKER_H
#include <stdint.h>
#include <base/DebugObject.h>
#include <flow/PacketRecvInterface.h>
/**
* {@link PacketRecvInterface} layer which blocks all output recv calls and only
* passes a single blocked call on to input when the user wants so.
*/
typedef struct {
PacketRecvInterface output;
int out_have;
uint8_t *out;
int out_input_blocking;
PacketRecvInterface *input;
DebugObject d_obj;
} PacketRecvBlocker;
/**
* Initializes the object.
*
* @param o the object
* @param input input interface
*/
void PacketRecvBlocker_Init (PacketRecvBlocker *o, PacketRecvInterface *input, BPendingGroup *pg);
/**
* Frees the object.
*
* @param o the object
*/
void PacketRecvBlocker_Free (PacketRecvBlocker *o);
/**
* Returns the output interface.
* The MTU of the output interface will be the same as of the input interface.
*
* @param o the object
* @return output interface
*/
PacketRecvInterface * PacketRecvBlocker_GetOutput (PacketRecvBlocker *o);
/**
* Passes a blocked output recv call to input if there is one and it has not
* been passed yet. Otherwise it does nothing.
* Must not be called from input Recv calls.
* This function may invoke I/O.
*
* @param o the object
*/
void PacketRecvBlocker_AllowBlockedPacket (PacketRecvBlocker *o);
#endif