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/* Copyright (C) 2003 MySQL AB
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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
#ifndef SHM_Transporter_H
#define SHM_Transporter_H
#include "Transporter.hpp"
#include "SHM_Buffer.hpp"
#ifdef NDB_WIN32
typedef Uint32 key_t;
#endif
/**
* class SHMTransporter
* @brief - main class for the SHM transporter.
*/
class SHM_Transporter : public Transporter {
friend class TransporterRegistry;
public:
SHM_Transporter(TransporterRegistry &,
const char *lHostName,
const char *rHostName,
int r_port,
bool isMgmConnection,
NodeId lNodeId,
NodeId rNodeId,
NodeId serverNodeId,
bool checksum,
bool signalId,
key_t shmKey,
Uint32 shmSize);
/**
* SHM destructor
*/
virtual ~SHM_Transporter();
/**
* Do initialization
*/
bool initTransporter();
Uint32 * getWritePtr(Uint32 lenBytes, Uint32 prio)
{
return (Uint32 *)writer->getWritePtr(lenBytes);
}
void updateWritePtr(Uint32 lenBytes, Uint32 prio)
{
writer->updateWritePtr(lenBytes);
m_last_signal += lenBytes;
if(m_last_signal >= m_signal_threshold)
{
doSend();
}
}
void getReceivePtr(Uint32 ** ptr, Uint32 ** eod){
reader->getReadPtr(* ptr, * eod);
}
void updateReceivePtr(Uint32 * ptr){
reader->updateReadPtr(ptr);
}
protected:
/**
* disconnect a segmnet
* -# deletes the shm buffer associated with a segment
* -# marks the segment for removal
*/
void disconnectImpl();
/**
* Blocking
*
* -# Create shm segment
* -# Attach to it
* -# Wait for someone to attach (max wait = timeout), then rerun again
* until connection established.
* @param timeOutMillis - the time to sleep before (ms) trying again.
* @returns - True if the server managed to hook up with the client,
* i.e., both agrees that the other one has setup the segment.
* Otherwise false.
*/
virtual bool connect_server_impl(NDB_SOCKET_TYPE sockfd);
/**
* Blocking
*
* -# Attach to shm segment
* -# Check if the segment is setup
* -# Check if the server set it up
* -# If all clear, return.
* @param timeOutMillis - the time to sleep before (ms) trying again.
* @returns - True if the client managed to hook up with the server,
* i.e., both agrees that the other one has setup the segment.
* Otherwise false.
*/
virtual bool connect_client_impl(NDB_SOCKET_TYPE sockfd);
bool connect_common(NDB_SOCKET_TYPE sockfd);
bool ndb_shm_create();
bool ndb_shm_get();
bool ndb_shm_attach();
/**
* Check if there are two processes attached to the segment (a connection)
* @return - True if the above holds. Otherwise false.
*/
bool checkConnected();
/**
* Initialises the SHM_Reader and SHM_Writer on the segment
*/
void setupBuffers();
/**
* doSend (i.e signal receiver)
*/
void doSend();
int m_remote_pid;
Uint32 m_last_signal;
Uint32 m_signal_threshold;
private:
bool _shmSegCreated;
bool _attached;
bool m_connected;
key_t shmKey;
volatile Uint32 * serverStatusFlag;
volatile Uint32 * clientStatusFlag;
bool setupBuffersDone;
#ifdef NDB_WIN32
HANDLE hFileMapping;
#else
int shmId;
#endif
int shmSize;
char * shmBuf;
SHM_Reader * reader;
SHM_Writer * writer;
/**
* @return - True if the reader has data to read on its segment.
*/
bool hasDataToRead() const {
return reader->empty() == false;
}
};
#endif
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