index : libvirt-python-split.git	master
	Unnamed repository; edit this file 'description' to name the repository.	Daniel Berrangé

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path: root/libvir-python-api.xml

	Commit message (Collapse)	Author	Age	Files	Lines
*	* Makefile.am configure.in libvir.spec.in python/*: added a firstv0.0.1	Daniel Veillard	2005-12-19	1	-0/+3
	version for python bindings, heavilly based on libxml2/libxslt way of doing things, maybe this need to be revisited. Added packaging too. * src/hash.h: fixed the Copyright notice. Daniel

generated by cgit (git 2.34.1) at 2026-01-20 13:40:46 +0000

/*
* This file is part of rasdaman community.
*
* Rasdaman community 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 3 of the License, or
* (at your option) any later version.
*
* Rasdaman community 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 rasdaman community.  If not, see <http://www.gnu.org/licenses/>.
*
* Copyright 2003, 2004, 2005, 2006, 2007, 2008, 2009 Peter Baumann /
rasdaman GmbH.
*
* For more information please see <http://www.rasdaman.org>
* or contact Peter Baumann via <baumann@rasdaman.com>.
/
/**
 * SOURCE: rasmgr_master_nb.cc
 *
 * MODULE: rasmgr
 * CLASS:  MasterComm
 *
 * PURPOSE:
 *   Main loop of master rasmgr
 *    
 * COMMENTS:
 * - MasterComm::processRequest() is the central dispatcher for rasmgr requests, recognising and executing them.
 *
*/

#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#include "rasmgr_master.hh"
#include "rasmgr_config.hh"
#include "rasmgr_rascontrol.hh"
#include "rasmgr_users.hh"
#include "rasmgr_host.hh"
#include "rasmgr_localsrv.hh"
#include "rasmgr_srv.hh"

using namespace std;

#include "debug.hh"


// from rasmgr_localsrv.cc; should go to a central location -- PB 2003-nov-25
extern char *now();

// rasserver error codes (see errtxts)
// FIXME: should go into a central include file / class -- PB 2003-nov-20
#define MSG_OK			200
#define MSG_OK_STR			"Ok"
#define MSG_UNKNOWNSERVERTYPE	1001
#define MSG_UNKNOWNSERVERTYPE_STR	"Unknown server type"
#define MSG_UNKNOWNACCESSTYPE	1002
#define MSG_UNKNOWNACCESSTYPE_STR	"Unknown access type"
#define MSG_DATABASENOTFOUND	807
#define MSG_DATABASENOTFOUND_STR	"Database not found"
#define MSG_WRITETRANSACTION	806
#define MSG_WRITETRANSACTION_STR	"Write transaction in progress"
#define MSG_NOSUITABLESERVER	805
#define MSG_NOSUITABLESERVER_STR	"No suitable servers started"
#define MSG_SYSTEMOVERLOADED	801
#define MSG_SYSTEMOVERLOADED_STR	"System overloaded"
// the following code means: I got an error code which I don't know (FIXME: reconsider nr!)
#define MSG_ILLEGAL		999
#define MSG_ILLEGAL_STR			"Internal error: Illegal response code."

// here I start collecting rasmgr protocol tokens to eventually gather them all in one include file
#define RASMGRPROT_EOL		"\r\n"
#define RASMGRPROT_DOUBLE_EOL	"\r\n\r\n"

// time [secs] until a client can be freed from the pending request list after a fake request
#define WAITTIME_AFTER_FAKE	2
// time increment [secs] of iterated timeout (see updateTime())
#define WAITTIME_REPEATED	3


MasterComm::MasterComm()
  { commit=false;
    allowMultipleWriteTransactions = false;
   }
   
MasterComm::~MasterComm()
  { 
   }

void MasterComm::Run()
  {
    ENTER("MasterComm::Run: enter." );

    initListenSocket(config.getListenPort());		// connect/bind the central listen socket
							// using IOSelector level here!

    initJobs(MAXJOBSMASTER);				// init jobs structure (nothing with sockets here)
    
    allowMultipleWriteTransactions = config.allowMultipleWriteTransactions();
    
    selector.setTimeout( config.getPollFrequency() , 0 );
    
    VLOG << "Entering server mode, prepared to receive requests." << endl << endl;

    while(mayExit()==false)
    {         
        TALK("MasterComm::Run: new request cycle, status before processing is:" );
        printStatus(); 

        if(commit)
            doCommit();
	   
	int answerLen=0;

        TALK("MasterComm::Run: (c) Waiting...");

        // wait for incoming requests, using select()
        int r=selector.waitForRequest();		// 0 is timeout, <0 error, >0 success
							// again, IOSelector level here!

	TALK("MasterComm::Run: (d) It's ringing..." << r);

	localServerManager.cleanChild(); // sa fie

	if(r<0) 					// nothing to read
	  {
            TALK("MasterComm::Run: (f1) it's a signal (or a socket failure)...");
	    continue;
          }
        if(r==0)					// timeout, nothing to read
	  {
            TALK("MasterComm::Run: (f2) nothing, look for timeouts...");
            lookForTimeout();
	    continue;
	  }
	if(r>0)						// something is pending
	  { 
	  
	    TALK("MasterComm::Run: (e) Got request, r=" << r << "...");

            // iterate over all jobs to see what we can read / reconnect (?) / write
	    dispatchWriteRequest(); // first this, to increase the chance to free a client
            connectNewClients();			// wait for requests, using accept()
            dispatchReadRequest();			// now read in new requests

	    for(int i=0;i<maxJobs;i++)
              {
                TALK( "- request processing: " << i );	// fake similar entry to benchmark logger
		// creates too large log files, so omit in production:
                // BenchmarkTimer *bPtr = new BenchmarkTimer("request processing");// print job start time to log

                processJob(job[i]);			// this can involve closing the connection!

		// creates too large log files, so omit in production:
                // bPtr->result();				// print stop time to log
              }
          }
      }
    LEAVE("MasterComm::Run: leave." );
   } // Run()

// keep connection open after processing request?
// ...according to request type and comm success, shall we keep socket open?
// Note: this is a bad hack, but I don't want to change the "answer" ret code of processRequest() unless I fully understand it -- PB 2003-jun-10
static bool keepConnection;

void MasterComm::processJob(NbJob &currentJob)
  {
    ENTER( "MasterComm::processJob: enter." );

    if(currentJob.isOperationPending()==false )
      {
        LEAVE( "MasterComm::processJob: leave. isOperationPending=false" );
        return;
      }

    if(currentJob.wasError())				// low-level comm error
      {
        TALK( "MasterComm::processJob: closing connection." );
        currentJob.closeConnection();
        LEAVE( "MasterComm::processJob: leave." );
        return;
      }
		
    if(currentJob.isMessageOK() == false)
      {
        LEAVE( "MasterComm::processJob: leave. isMessageOK=false" );
        return;
      }
    
    if(fillInBuffer(currentJob.getMessage())==false)	// fill msg into answer buffer header + body
      {
        TALK( "MasterComm::processJob: closing connection." );
        currentJob.closeConnection();
        LEAVE( "MasterComm::processJob: leave. fillInBuffer=false" );
        return;
      }

    // now we have the message in inBuffer, with header and body set correctly		

    int answer = processRequest( currentJob );	

    int outLen = strlen(outBuffer);
    
    if(outLen && answer != 2) // sending the answer
					// FIXME: what is answer==2 ? never happens! -- PB 2003-jun-10
      { 
        TALK( "MasterComm::processJob: init sending answer for outBuffer, set socket to write mode." );
        currentJob.initSendAnswer(outBuffer);
      }
      
    if(outLen == 0) // no answer to send
      { 
        TALK( "MasterComm::processJob: no answer to send, closing connection." );
        currentJob.closeConnection();
      }  

     if( answer == 1 ) // means "delayedOperation"
					// FIXME: according to processRequest, delOp is 0 !!! -- PB 2003-jun-10
					// ...and 1 comes back for POST rasservernewstatus
       { // the only known until now
        TALK( "MasterComm::processJob: delayedOp, therefore changeServerStatus()." );
         rasManager.changeServerStatus(body);
       }	  
     /* Two words about this delayedOperation. If a remote server crashes, the remote rasmgr
        sends a message and does not wait for answer. But if the master rasmgr restarts 
	immediately the crashed server, it could come to a deadlock. Maybe not, but we
	wish to avoid any possibility, so we close first the connection and then attempt
	to restart the server.
      */	

    // EXPERIMENTAL: close sockets as soon and as always as possible
    // if (! keepConnection)		// singleton request or comm error
      // {
        // TALK( "MasterComm::processJob: singleton request, closing connection." );
        // currentJob.closeConnection();
      // }

    LEAVE( "MasterComm::processJob: leave." );
   }  // processJob() 


// printClientAddr(): aux fct to print client address to designated stream
const char *getClientAddr( int mySocket )
{
	const char *result = NULL;
	struct sockaddr_in s;
	socklen_t sockaddrSize = (socklen_t) sizeof(s);
	if ( getpeername( mySocket, (struct sockaddr*)&s, &sockaddrSize ) != 0)
		result = strerror(errno);
	else
		result = inet_ntoa(s.sin_addr);
	return result;
}

// process request which has been prepared in inBuffer
// if 'verbose' is enabled in configuration then requests will be logged.
// returns 
//	0 normally (?)
//	1 for POST rasservernewstatus
// NB: keepConnection is static above -- bad hack, see there
int MasterComm::processRequest( NbJob &currentJob )
{ 
	ENTER( "MasterComm::processRequest: enter. inBuffer=" << inBuffer );

	// inBuffer: header + body Ok, output in outBuffer, which is not initialized here
	outBuffer[0]=0;		// mark outBuffer as empty
	int answer = 0;	
	// delayedOperation = 0;

	bool fake = false;	// getfreeserver request really wants to allocate a new server?
   
	// --- this is the central dispatcher for rasmgr requests, recognising and executing them.

	if(isMessage("POST rasmgrslave")) 
	{
		VLOG << now() << " slave rasmgr request from "
		     << getClientAddr( currentJob.getSocket() )
		     << ": '" << body << "'..." << flush;

		hostmanager.postSlaveMGR(body,outBuffer);	// prepare outBuffer from body for send to slave
		keepConnection = false;				// master mgr passes thru, it's singleton commo, so don't keep conn
								// FIXME: is this really correct?? -- PB 2003-jun-10
		VLOG << "ok" << endl;
	}
	else if(isMessage("POST rasservernewstatus"))
	{
		// extract server status from msg body
		char serverName[50];
		int  newstatus = 0;
		long dummy = 0;
		serverName[0] = '\0';	// initialize in case sscanf() fails

		int result = sscanf( body, "%s %d %ld", serverName, &newstatus, &dummy);
		if (result == 3)				// we simply ignore malformed requests, reason see below
		{
			const char *statusText = NULL;
			switch (newstatus)
			{
				case SERVER_DOWN:
					statusText = SERVER_DOWN_TXT;
					break;
				case SERVER_AVAILABLE:
					statusText = SERVER_AVAILABLE_TXT;
					break;
				case SERVER_REGULARSIG:
					statusText = SERVER_REGULARSIG_TXT;
					break;
				case SERVER_CRASHED:
					statusText = SERVER_CRASHED_TXT;
					break;
				default:
					statusText = "(unknown message flag)";
					break;
			}
			if (newstatus != SERVER_REGULARSIG)	// don't blow up the log file with "still alive" signals
			{
				VLOG << now() << " status info from server " << serverName
				     << " @ " << getClientAddr( currentJob.getSocket() )
				     << ": '" << statusText << "'...ok" << endl;
			}

			keepConnection = false;			// singleton msg slave -> master
			answer = 1; 
		}
		else // malformed request
		{
			VLOG << now() << " Error: malformed request (ignoring it) from "
			     << getClientAddr( currentJob.getSocket() )
			     << ": '" << body << "'" << endl;
		}
	}
	else if( (fake = isMessage("POST getfreeserver2")) || isMessage("POST getfreeserver")) 
	{ 
		VLOG << now() << " client request from "
		     << getClientAddr( currentJob.getSocket() )
		     << ": " << "'get server'..." << flush;

			int rc = getFreeServer(fake);	// returns std rasdaman errors -- FIXME: error ignored!
			keepConnection = (rc == MSG_OK) ? true : false;	// 200 is "ok"
			VLOG << "ok" << endl;
	   

	}	  
	else if(isMessage("POST rascontrol")) 
	{ 
		VLOG << now() << " rascontrol request from "
		     << getClientAddr( currentJob.getSocket() )
		     << ": '" << body << "'..." << flush;

		if(authorization.acceptEntry(header))
		{
			rascontrol.processRequest(body,outBuffer);	        
			keepConnection = true;		// rascontrol connection accepted, so keep it
			VLOG << "ok" << endl;
		}
		else
		{
			answerAccessDenied();
			keepConnection = false;		// this is a final answer, don't keep conn open afterwards
			VLOG << "denied." << endl;
		}
	}	     
	
	LEAVE( "MasterComm::processRequest: leave. answer=" << answer << ", keepConnection=" << keepConnection );
	return answer;
} // processRequest()

// fillInBuffer: fill parameter string passed into message header and body (both global)
// separator is a double newline
// FIXME: unstable and weird programming, improve! -- PB 2003-jun-10
// input:
//	s	message input string
// returns:
//	true	filled buffer properly
//	false	NULL body string
//	inBuffer	(global buffer) set to s; header string part properly NULL terminated in inBuffer
//	body	(global ptr) set to beginning of message body in inBuffer
//	header	(global ptr) set to beginning of inBuffer
bool MasterComm::fillInBuffer(const char *s)
{  
	strcpy(inBuffer,s);
	header=inBuffer;				// set header to begining of msg buffer
	body=strstr(inBuffer, RASMGRPROT_DOUBLE_EOL );	// find double EOL, this is where body starts
	if(body == NULL)				// not found? this means a protocol syntax error
	{
		TALK( "MasterComm::fillInBuffer: Error in rasmgr protocol encountered (2xEOL missing). msg=" << inBuffer );
		return false; // only if client is stupid 
	}

	*body=0;					// terminate header (!) string
	body+= strlen( RASMGRPROT_DOUBLE_EOL );		// let body start after this double newline

	return true;
}

// save config and auth file; deprecated
void MasterComm::doCommit()
{ 
   if(config.isTestModus()==false)
     { 
      TALK( "MasterComm::doCommit: deprecated, should not be called any longer." );
#if 0 // now done by saveCommand() directly
      if(commitAuthOnly==false)
        { VLOG << "Save configuration file...";
          if(config.saveConfigFile()) VLOG << "OK" << std::endl;
          else                        VLOG << "Failed" << std::endl;
	 } 
	    
       VLOG << "Save authorization file...";
       if(authorization.saveAuthFile()) VLOG << "OK" << std::endl;
       else                             VLOG << "Failed" << std::endl;
#endif
      }
   else
     { std::cout<<"Save requested, but not permitted during test modus!"<<std::endl;
      }   	     
   commit=false;
  }
         
void MasterComm::commitChanges()
  { commit=true;
    commitAuthOnly=false;
   }
void MasterComm::commitAuthFile()
  { commit=true;
    commitAuthOnly=true;
   }
   
int MasterComm::answerAccessDenied()
  { // send to rascontrol when wrong login
    sprintf(outBuffer,"HTTP/1.1 400 Error\r\nContent-type: text/plain\r\nContent-length: %d\r\n\r\nAccess denied",strlen("Access denied")+1);
    return strlen(outBuffer)+1;
   }

int MasterComm::answerAccessDeniedCode()
  { // send to clients requesting free server when wrong login
    sprintf(outBuffer,"HTTP/1.1 400 Error\r\nContent-type: text/plain\r\nContent-length: %d\r\n\r\n802 Access denied",strlen("802 Access denied")+1);
    return strlen(outBuffer)+1;
   }

// input:
//	fake	true if only testing, false if server is to be allocated
//	body	(global var) holding string encoding of request parameters
//		syntax: <dbname> [RPC|HTTP|RNP] [rw|ro] <previousID>
//			where the flags are NOT case sensitive
// returns: standard rasdasman error codes
//	200 (ok), 801, 805, 999, ...
int MasterComm::getFreeServer(bool fake)
{ 
	// creates too large log files, so omit in production:
	// BenchmarkTimer *freeServerTimePtr = new BenchmarkTimer("Get free server");
	
	char databaseName[100];
	char serverType[10]; 
	char serverName[100]; 		// name of rasserver found, if any
	char accessType[5];
	char prevID[200]="(none)";

	ENTER("MasterComm::getFreeServer: enter. fake=" << fake << ", body="<<body<<'*');

	// initialize server name
	strcpy( serverName, "(none)" );

	// extract components from body string
	int count = sscanf(body,"%s %s %s %s",databaseName,serverType,accessType, prevID);
	if (count != 4 && count != 3)
	{
		cout << "Error (internal): Cannot parse msg body received from client." << endl;
		LEAVE("MasterComm::getFreeServer: leave. Fatal error: cannot parse msg body string '" << body << "'" );
		return MSG_ILLEGAL;
	}

	ClientID clientID;
	// if we got a previous ID then take this one
	if(count >3)
		clientID.init(prevID); 
	
	TALK("GetFreeServer: db = " << databaseName << ", requested server type = " << serverType << ", access type = " << accessType << ", clientID="<<clientID<<" prevID="<< prevID );
	
	char sType=0;					// type of server requested, values SERVERTYPE_*
	bool writeTransaction;				// true <=> write transaction requested
	
	int  answCode=MSG_OK;				// request answer code
	const char *answText=MSG_OK_STR;		// string representation of above answer code

	char answerString[200]="";			// response string sent back to caller

	// this loop is executed at most once, it servers only to have
	// a well-defined point of continuation upon evaluation errors
	do	
	{
		// --- evaluate message body ------------------------

		// determine server type requested
		if(strcasecmp(serverType,"HTTP")==0)
			sType=SERVERTYPE_FLAG_HTTP;
		if(strcasecmp(serverType,"RPC")==0)
			sType=SERVERTYPE_FLAG_RPC;
		if(strcasecmp(serverType,"RNP")==0)
			sType=SERVERTYPE_FLAG_RNP;
		if(sType==0)
		{
			cout << "Error: unknown server type: " << serverType << endl;
			answCode=MSG_UNKNOWNSERVERTYPE;
			break;
		}

		// determine transaction mode
		if (strcasecmp(accessType,"ro")==0)
			writeTransaction=false;
		else if (strcasecmp(accessType,"rw")==0)
			writeTransaction=true;
		else
		{
			cout << "Error: unknown transaction type: " << accessType << endl;
			answCode=MSG_UNKNOWNACCESSTYPE;
			break;
		}

		TALK("accessType="<<accessType<<" writeTransaction="<<writeTransaction);       
		
		// --- check against database state ------------------------

		// does requested database exist? (i.e., is it known?)
		Database &db=dbManager[databaseName];
		if(db.isValid()==false)
		{
			cout << "Error: database not found: " << databaseName << endl;
			answCode=MSG_DATABASENOTFOUND;
			break;
		}

		// if r/w TA requested: is this compatible with the database's transaction state?
		if(writeTransaction==true && db.getWriteTransactionCount() && allowMultipleWriteTransactions == false)
		{
			cout << "Error: write transaction in progress, conflicts with request." << endl;
			answCode=MSG_WRITETRANSACTION;
			break;
		}
		
		// --- all fine, try to find a free server ------------------------

		// iterate over registered servers, try to find a free one
		// FIXME: should be "round robin" strategy wrt server hosts;
		// take last used per server host is fine to reduce swapping
		int countSuitableServers=0;		// number of servers we can choose from
		TALK( "starting to search for server of type " << sType << "..." );
		for(int i=0; i<db.countConnectionsToRasServers(); i++)
		{
			// inspect next server
			RasServer &r=rasManager[db.getRasServerName(i)];
			TALK( "  srv #" << i << ": name=" << r.getName() << ", type=" << r.getType() << ", isUp=" << r.isUp() << ", isAvailable=" << r.isAvailable() );
			if(sType == r.getType()) 	// type matches request?
			{ 
				if(r.isUp())		// server is up?
					countSuitableServers++;
			
				if(r.isAvailable())	// server is free?
				{	// part A: we have what you want
					int cbs = clientQueue.canBeServed(clientID, (const char*)databaseName, sType, fake); 
					// returns: 0=OK, otherwise rasdaman errors 801, 805 -- PB 2003-nov-20
					if(cbs != 0)
					{ 
						TALK("MasterComm::getFreeServer: clientQueue.canBeServed(" << clientID << "," << databaseName << "," << sType << "," << fake << ") -> " << cbs );
						cout << "Error: no server available, error code: " << cbs << endl;
						answCode = cbs;
						break;
					}
					if( fake == false)	// server to be allocated?
					{
						// mark server found as unavailable to others
						r.setNotAvailable();
						// set transaction mode requested
						if(writeTransaction==true)
							r.startWriteTransaction(db); // nothing real happens, no error can occur
						else
							r.startReadTransaction(db); // nothing real happens, no error can occur
						TALK("MasterComm::getFreeServer: You have the server.");
						// answCode is same as initialised if we come here
					}
					sprintf(answerString,"%s %ld %s ",r.getHostNetwName(),r.getPort(),authorization.getCapability(r.getName(),databaseName,!writeTransaction) );
					// remember server name
					strncpy( serverName, r.getName(), sizeof(serverName) );
;
					TALK( "answerString=" << answerString );
					break;
				}
			}	 
		} // for

		// any free server found?
		if(countSuitableServers == 0)
		{
			cout << "Error: no suitable free server available." << endl;
			answCode = MSG_NOSUITABLESERVER;
			break;
		}

		// no answer string provided -> no server available
		// oops?? why not uniformly check against answCode? -- PB 2003-nov-20
		if(answerString[0]==0)
		{
			cout << "Error: cannot find any free server; answer code: " << answCode << " -> ";
			answCode = MSG_SYSTEMOVERLOADED;
			cout << answCode << endl;
			break;
		}  
	
	} while(0); // see comment at start of "loop"
		
	answText = convertAnswerCode(answCode);
	 
	if(answCode == MSG_OK)
		sprintf(outBuffer,"HTTP/1.1 %d %s\r\nContent-type: text/plain\r\nContent-length: %d\r\n\r\n%s",answCode,answText,strlen(answerString)+1,answerString);
	else
	{
		sprintf(outBuffer,"HTTP/1.1 %d %s\r\nContent-type: text/plain\r\nContent-length: %d\r\n\r\n%d %s",400,"Error",strlen(answText)+1,answCode,answText);
		clientQueue.put(clientID, (const char*)databaseName, sType, answCode); 
	}
		
	// creates too large log files, so omit in production:
	// freeServerTimePtr->result();		// print time elapsed

	LEAVE("MasterComm::getFreeServer: leave. answCode=" << answCode << ", server=" << serverName << ", outBuffer=" << outBuffer );
	return answCode; //strlen(outBuffer)+1;    	 
} // getFreeServer()

// convertAnswerCode: convert numeric answer code to error text for selected errors + OK
// input:
//	code	numeric error code, cf. errtxts
// returns:
//	answer	ptr to static error text
const char* MasterComm::convertAnswerCode(int code)
{
	const char *answer = MSG_ILLEGAL_STR;	// return value, initialized to "illegal"
	switch(code)
	{
        	case MSG_OK:
			answer = MSG_OK_STR;
			break;
        	case MSG_UNKNOWNSERVERTYPE:
			answer = MSG_UNKNOWNSERVERTYPE_STR;
			break;
        	case MSG_UNKNOWNACCESSTYPE:
			answer = MSG_UNKNOWNACCESSTYPE_STR;
			break;
        	case MSG_DATABASENOTFOUND:
			answer = MSG_DATABASENOTFOUND_STR;
			break;
        	case MSG_WRITETRANSACTION:
			answer = MSG_WRITETRANSACTION_STR;
			break;
        	case MSG_NOSUITABLESERVER:
			answer = MSG_NOSUITABLESERVER_STR;
			break;
        	case MSG_SYSTEMOVERLOADED:
			answer = MSG_SYSTEMOVERLOADED_STR;
			break;
        	default: 
			// cout<<"Default value not allowed ="<<code<<endl; assert( 0 != 0); break;
			// no program aborts deeply inside!!! -- PB 2003-jun-25
                   	answer = MSG_ILLEGAL_STR;
			break;
	}

	TALK("MasterComm::convertAnswerCode: code=" << code << ", answer=" << answer );
	return answer;
}
	
// isMessage: determine whether header conforms with a given prefix; case insensitive
// input:
//	messageStart	prefix to compare with
//	header		(global) message header to be inspected
// returns:
//	true		on match
//	false		otherwise
bool MasterComm::isMessage(const char *messageStart)
{
	ENTER( "MasterComm::isMessage, messageStart=" << messageStart );

	bool rasp= (strncasecmp(header,messageStart,strlen(messageStart))==0) ? true:false;
	if(rasp)
		TALK("(b) Message="<<messageStart);

	LEAVE( "MasterComm::isMessage, result=" << rasp );
	return rasp;
}


//********************************************************************

ClientID::ClientID()
{
	valid = false;
}

   
void ClientID::init(const char *stringrep)
{
	idstring = stringrep;
	valid = true;
}

string ClientID::getID() const
{
	return idstring;
}

bool   ClientID::isValid() const
{
	return valid;
}
            
bool ClientID::operator==(const ClientID& cl)
{
	return (idstring == cl.idstring && valid) ? true : false;
}
   
bool ClientID::operator!=(const ClientID& cl)
{
	return (idstring == cl.idstring && valid) ? false : true;
}    
        
std::ostream& operator<<(std::ostream &os, const ClientID &cl)
{
	os<<cl.getID();
	return os;
}

// ----------------------------------------

/*
list of pending client requests.
requests are entered if for some reason server allocation failed, or if a "fake" request was sent.
*/
// member attributes are defined in rasmgr_master.hh

ClientQueue::ClientQueue()
{
	// do nothing
}

ClientQueue::~ClientQueue()
{
	// do nothing
}

// put: put client request into (static) queue; do nothing if request is malformed
// well formed if:
//	- valid client ID in clientID
//	- server assignment error in errorCode
void ClientQueue::put(ClientID &clientID, const char *dbName, char serverType, int errorCode)
{
	ENTER("ClientQueue::put: start, clientID=" << clientID << ", db=" << dbName << ", serverType=" << serverType << ", errorCode=" << errorCode );

	// --- input parameter check ---------------

	if(clientID.isValid() == false)		// invalid clientID's are not put in queue
		return; 

	if (errorCode != MSG_SYSTEMOVERLOADED
	 && errorCode != MSG_NOSUITABLESERVER
	 && errorCode != MSG_WRITETRANSACTION)	// only these codes are put in queue
        	return;    

	// --- walk through client list to find a matching entry ---------------

	ClientEntry *client = 0;		// ptr to a list entry

	// iterate thru list of client requests
	TALK( "iterating through list, client table size=" << clients.size() );
	for(int i=0;i<clients.size(); i++)
	{
		ClientEntry& curClient = clients[i];	// list entry to be inspected

		// on the fly, remove first list entry if outdated or inactive
		// FIXME: what an ugly code -- PB 2003-nov-20
		if(curClient.activ == false || curClient.isTimeout()) 
		{
			if(i==0) 			// do only for 1st element
			{
				TALK("ClientQueue::put: cleaned up client "<<curClient.clientID );
				clients.pop_front();	// remove this first element
				i--; // set back loop ctr
			}
			continue;
		}

		// have an entry with matching client ID?
		if(curClient.clientID == clientID)
 		{
			client = &clients[i];		// remember this entry
			break;
		}