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/* |
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* PearPC |
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* sysethtun.h |
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* |
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* Abstraction for ethernet tunnel devices |
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* |
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* Copyright (C) 2003,2004 Stefan Weyergraf |
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* |
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* This program is free software; you can redistribute it and/or modify |
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* it under the terms of the GNU General Public License version 2 as |
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* published by the Free Software Foundation. |
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* |
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* This program is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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* GNU General Public License for more details. |
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* |
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* You should have received a copy of the GNU General Public License |
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* along with this program; if not, write to the Free Software |
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
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*/ |
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|
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#ifndef __SYSETHTUN_H__ |
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#define __SYSETHTUN_H__ |
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|
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#include "system/types.h" |
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|
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// FIXME: reentrancy, threading specs |
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|
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class PacketDevice { |
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public: |
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virtual ~PacketDevice() {} |
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|
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/** |
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* Read a packet from the device into a buffer |
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* |
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* @param buf pointer to a buffer containing the packet data |
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* @param size size of the buffer |
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* @returns number of bytes received and written into buf |
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*/ |
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virtual uint recvPacket(void *buf, uint size) = 0; |
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|
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/** |
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* Wait for a packet to be received |
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* |
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* This function blocks the calling thread until a packet is received |
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* or an error occurs. It should do this in a manner that consumes |
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* little to low CPU time. |
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* If the function succeeds the next call to recvPacket() is |
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* "very likely" to succeed as well. |
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* |
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* @returns 0 on success, non-zero in case of error (the result is |
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* an errno. Ie. you can use it in strerror()) |
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*/ |
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virtual int waitRecvPacket() = 0; |
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|
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/** |
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* Write a packet from a buffer into the device |
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* |
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* @param buf pointer to a buffer containing the packet data |
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* @param size size of the buffer |
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* @returns number of bytes sent and written into buf |
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*/ |
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virtual uint sendPacket(void *buf, uint size) = 0; |
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}; |
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|
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/** |
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* An ethernet tunnel is a virtual ethernet line connecting the operating |
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* system's networking stack with some other piece of software (as opposed |
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* to a physical ethernet cable, connecting two pieces of hardware). |
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* |
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* This class represents one end-point of the tunnel, the aforementioned |
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* "piece of software". Both sides should be configured to have their own |
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* separate network addresses (e.g. MAC and IP addresses). |
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* |
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* The packets sent and received are ethernet specific Ethernet-II |
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* frames with IEEE 802.3 MAC addresses, prefixed by a specific number of |
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* bytes (for use by the networking stack). |
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*/ |
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class EthTunDevice: public PacketDevice { |
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public: |
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virtual ~EthTunDevice() {} |
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|
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/** |
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* Get driver-specific ethernet write frame prefix. |
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* |
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* When writing packets, a specific number of bytes in the packet |
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* buffer must be dedicated to the system's networking stack. The |
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* actual ethernet frame follows after this area. |
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* |
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* @returns number of bytes in write frame prefix |
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*/ |
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virtual uint getWriteFramePrefix() = 0; |
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/** |
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* Initialize the device. |
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* |
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* @returns init status (0 = ok) |
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*/ |
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virtual int initDevice() = 0; |
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/** |
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* Uninitialize the device. |
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* |
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* @returns shutdown status (0 = ok) |
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*/ |
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virtual int shutdownDevice() = 0; |
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}; |
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|
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/* system-dependent (implementation in $MYSYSTEM/ *.cc) */ |
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extern EthTunDevice *createEthernetTunnel(); |
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|
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#endif /* __SYSETHTUN_H__ */ |