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// -*- c++ -*-
//------------------------------------------------------------------------------
// fork_test.cpp
//------------------------------------------------------------------------------
// $Id: fork_test.cpp,v 1.5 2006/07/20 02:30:55 vlg Exp $
//------------------------------------------------------------------------------
// Copyright (c) 2002,2005 by Vladislav Grinchenko
//
// 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 is what happens in the test:
main
|
fork
/ \
fork A (WAIT) for (5 times) { sleep(1); print msg }
/ \
/ \
/ \
/ \
/ B (KILL)
fork
/ \
/ C (WAIT) for (5 times) { sleep(2); print msg }
/
done
Child B is killed immediately after main() exits. SIGTERM is
sent to child A and C and parent process waits for them to finish.
First finishes A, and then C.
Process D is not in the picuture because its state flag is LEAVE_ALONE.
init will become its parent and it shall be killed separately.
------------------------------------------------------------------------*/
#include <iostream>
#include <fstream>
using namespace std;
#include "assa/Logger.h"
#include "assa/Fork.h"
using namespace ASSA;
int
main (int argc, char** argv)
{
std::cout << "= Running fork_test Test =" << std::endl;
::unlink ("fork_A.log");
::unlink ("fork_B.log");
::unlink ("fork_C.log");
::unlink ("fork_D.log");
::unlink ("fork_test.log");
#if defined (WIN32)
std::cout
<< "= Running fork_test Test =\n"
<< "Spanning 3 child processes: A, B, and C\n"
<< "First B shall be terminated, then wait for A and C to finish.\n"
<< "Parent: forking A ...\n"
<< "Parent: forking B ...\n"
<< "Parent: forking C ...\n"
<< "Parent: forking D ...\n";
#else
// Log::open_log_file ("fork_test.log", APP);
Log::open_log_stdout (APP);
// Just test that it works at all
DL((APP,"Spanning 3 child processes: A, B, and C\n"));
DL((APP,"First B shall be terminated, then wait for A and "
"C to finish.\n"));
DL((APP,"Parent: forking A ...\n"));
LOGGER->log_resync ();
Fork a (Fork::WAIT_ON_EXIT, Fork::IGNORE_STATUS);
if (a.isParent()) {
DL((APP,"Parent: forking B ...\n"));
LOGGER->log_resync ();
Fork b (Fork::KILL_ON_EXIT, Fork::IGNORE_STATUS);
if (b.isParent()) {
DL((APP,"Parent: forking C ...\n"));
LOGGER->log_resync ();
Fork c (Fork::WAIT_ON_EXIT, Fork::IGNORE_STATUS);
if (c.isParent()) {
DL((APP,"Parent: forking D ...\n"));
LOGGER->log_resync ();
Fork d (Fork::LEAVE_ALONE, Fork::IGNORE_STATUS);
if ( d.isParent() ) {
//zombie = d.getChildPID ();
}
else { // Child D
Log::log_close ();
Log::open_log_file ("fork_D.log", APP);
DL((APP,"In child D ... sleeping 20 seconds.\n"));
sleep (20);
}
/* Exiting will trigger ForkList destructor
* that suppose to collect exiting status of children
*/
}
else if (c.isChild()) {
Log::log_close ();
Log::open_log_file ("fork_C.log", APP);
DL((APP,"In child C ..."
" print 5 msgs with 2 sec interval.\n"));
for (int i=0; i<5; i++) {
sleep(2);
DL((APP,"[%1d] child < C > is here\n", i+1));
}
DL((APP,"child C exits!\n"));
return 0;
}
}
else if (b.isChild()) {
Log::log_close ();
Log::open_log_file ("fork_B.log", APP);
DL((APP,"In child B - you should see it just once.\n"));
sleep(12);
/*
* you normally won't see this message becuase
* parent suppose to terminate this child with SIGTERM
*/
DL((APP,"child B exits!\n"));
return 0;
}
}
else if (a.isChild()) {
Log::log_close ();
Log::open_log_file ("fork_A.log", APP);
DL((APP,"In child A ... print 5 msgs with 1 sec interval.\n"));
for (int j=0; j<5; j++) {
sleep(1);
DL((APP,"[%d] child < A > is here\n", j+1));
}
DL((APP, "child A exits!\n"));
return 0;
}
#endif // !ifdef WIN32
return 0;
}
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