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/*
* PROGRAM: Object oriented API samples.
* MODULE: 08.events.cpp
* DESCRIPTION: A sample of working with events.
*
* Example for the following interfaces:
* IEvents - returned by queEvents(), used to cancel events monitoring
* IEventCallback - it's callback is invoked when event happens
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Initial Developer of the Original Code is Adriano dos Santos Fernandes.
* Portions created by the Initial Developer are Copyright (C) 2011 the Initial Developer.
* All Rights Reserved.
*
* Contributor(s):
* Alexander Peshkov
*/
#include "ifaceExamples.h"
#ifndef WIN32
#include <unistd.h>
#else
#include <windows.h>
#endif
static IMaster* master = fb_get_master_interface();
namespace
{
// This class encapsulates single event handling
class Event : public IEventCallbackImpl<Event, ThrowStatusWrapper>
{
public:
Event(IAttachment* aAttachment, const char* name)
: refCounter(0),
attachment(aAttachment),
counter(0),
status(master->getStatus()),
events(NULL),
first(true)
{
eveLen = isc_event_block(&eveBuffer, &eveResult, 1, name);
events = attachment->queEvents(&status, this, eveLen, eveBuffer);
}
void process(int pass)
{
if (!events)
return;
ISC_ULONG tot = 0;
if (counter)
{
isc_event_counts(&tot, eveLen, eveBuffer, eveResult);
events->release();
events = NULL;
counter = 0;
events = attachment->queEvents(&status, this, eveLen, eveBuffer);
}
if (tot && !first)
printf("Event count on pass %d is %d\n", pass, tot);
else
printf("Pass %d - no events\n", pass);
first = false;
}
// IEventCallback implementation
void eventCallbackFunction(unsigned int length, const ISC_UCHAR* data)
{
memcpy(eveResult, data, length);
++counter;
if (!first)
printf("AST called\n");
}
// refCounted implementation
virtual void addRef()
{
++refCounter;
}
virtual int release()
{
if (--refCounter == 0)
{
delete this;
return 0;
}
else
return 1;
}
private:
~Event()
{
if (events)
events->release();
if (eveBuffer)
isc_free((char*)eveBuffer);
if (eveResult)
isc_free((char*)eveResult);
status.dispose();
}
FbSampleAtomic refCounter;
IAttachment* attachment;
volatile int counter;
ThrowStatusWrapper status;
IEvents* events;
unsigned char* eveBuffer;
unsigned char* eveResult;
unsigned eveLen;
bool first;
};
}
int main()
{
int rc = 0;
// set default password if none specified in environment
setenv("ISC_USER", "sysdba", 0);
setenv("ISC_PASSWORD", "masterkey", 0);
// With ThrowStatusWrapper passed as status interface FbException will be thrown on error
ThrowStatusWrapper status(master->getStatus());
// Declare pointers to required interfaces
IProvider* prov = master->getDispatcher();
IAttachment* att = NULL;
ITransaction* tra = NULL;
Event* event = NULL;
try
{
// attach database
att = prov->attachDatabase(&status, "employee", 0, NULL);
// register an event
event = new Event(att, "EVENT1");
event->addRef();
const char cmdBlock[] = "execute block as begin post_event 'EVENT1'; end";
for (int i = 0; i < 3; ++i)
{
#ifndef WIN32
sleep(1); // sec
#else
Sleep(1000); // msec
#endif
event->process(i);
tra = att->startTransaction(&status, 0, NULL);
att->execute(&status, tra, 0, cmdBlock, SAMPLES_DIALECT,
NULL, NULL, NULL, NULL);
tra->commit(&status);
tra = NULL;
}
// cleanup
event->release();
event = NULL;
att->detach(&status);
att = NULL;
}
catch (const FbException& error)
{
// handle error
rc = 1;
char buf[256];
master->getUtilInterface()->formatStatus(buf, sizeof(buf), error.getStatus());
fprintf(stderr, "%s\n", buf);
}
// release interfaces after error caught
if (event)
event->release();
if (tra)
tra->release();
if (att)
att->release();
// generic cleanup
prov->release();
status.dispose();
return rc;
}
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