/*
* Copyright (c) 2005, Bull S.A..  All rights reserved.
* Created by: Sebastien Decugis

* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write the Free Software Foundation, Inc., 59
* Temple Place - Suite 330, Boston MA 02111-1307, USA.


* This sample test aims to check the following assertion:
*
*  Destruction of the semaphore is postponed until all processes which were using
* the semaphore have called sem_close, _exit or exec.



* The steps are:
* -> Create a named semaphore with value = 0.
* -> create 3 processes. Each call sem_wait, then sem_post, then sem_close/_exit/exec
* -> the main process unlinks the semaphore, the posts it and close it.
* -> Check all child processes have returned successfully.

* The test fails if a semaphore operation returns an error in one of the children.

*/

/* We are testing conformance to IEEE Std 1003.1, 2003 Edition */
#define _POSIX_C_SOURCE 200112L

/******************************************************************************/
/*************************** standard includes ********************************/
/******************************************************************************/
#include <pthread.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include <semaphore.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/wait.h>

/******************************************************************************/
/***************************   Test framework   *******************************/
/******************************************************************************/
#include "testfrmw.h"
#include "testfrmw.c" 
/* This header is responsible for defining the following macros:
 * UNRESOLVED(ret, descr);  
 *    where descr is a description of the error and ret is an int 
 *   (error code for example)
 * FAILED(descr);
 *    where descr is a short text saying why the test has failed.
 * PASSED();
 *    No parameter.
 * 
 * Both three macros shall terminate the calling process.
 * The testcase shall not terminate in any other maneer.
 * 
 * The other file defines the functions
 * void output_init()
 * void output(char * string, ...)
 * 
 * Those may be used to output information.
 */

/******************************************************************************/
/**************************** Configuration ***********************************/
/******************************************************************************/
#ifndef VERBOSE
#define VERBOSE 1
#endif

#define SEM_NAME  "/sem_unlink_9_1"

/******************************************************************************/
/***************************    Test case   ***********************************/
/******************************************************************************/

/* Operations common to all processes on the semaphore*/
sem_t * common()
{
	int ret;
	sem_t * sem;

	/* Reconnect to the semaphore */
	sem = sem_open( SEM_NAME, 0 );

	if ( sem == SEM_FAILED )
	{
		UNRESOLVED( errno, "Failed to reconnect the semaphore" );
	}


	/* block until the semaphore is posted */

	do
	{
		ret = sem_wait( sem );
	}
	while ( ( ret != 0 ) && ( errno == EINTR ) );

	if ( ret != 0 )
	{
		FAILED( "Waiting for the semaphore failed" );
	}

	/* spend some time... */
	sched_yield();

	sched_yield();

	sched_yield();

	/* Post the semaphore back */
	ret = sem_post( sem );

	if ( ret != 0 )
	{
		FAILED( "Failed to post the semaphore" );
	}

	return sem;
}

/* The main test function. */
int main( int argc, char * argv[] )
{
	int ret, status;
	pid_t p1, p2, p3, ctl;

	sem_t * sem;

	/* Initialize output */
	output_init();

	/* Create the semaphore */
	sem = sem_open( SEM_NAME, O_CREAT | O_EXCL, 0777, 0 );

	if ( ( sem == SEM_FAILED ) && ( errno == EEXIST ) )
	{
		sem_unlink( SEM_NAME );
		sem = sem_open( SEM_NAME, O_CREAT | O_EXCL, 0777, 0 );
	}

	if ( sem == SEM_FAILED )
	{
		UNRESOLVED( errno, "Failed to create the semaphore" );
	}

	/* fork 3 times */
	p1 = fork();

	if ( p1 == ( pid_t ) - 1 )
	{
		UNRESOLVED( errno, "Failed to fork" );
	}

	if ( p1 == ( pid_t ) 0 )        /* child */
	{
		sem = common();
		ret = sem_close( sem );

		if ( ret != 0 )
		{
			FAILED( "Failed to sem_close in child" );
		}

		exit( 0 );
	}

	p2 = fork();

	if ( p2 == ( pid_t ) - 1 )
	{
		UNRESOLVED( errno, "Failed to fork" );
	}

	if ( p2 == ( pid_t ) 0 )        /* child */
	{
		sem = common();
		_exit( 0 );
	}

	p3 = fork();

	if ( p3 == ( pid_t ) - 1 )
	{
		UNRESOLVED( errno, "Failed to fork" );
	}

	if ( p3 == ( pid_t ) 0 )        /* child */
	{
		sem = common();
		ret = execl( "/bin/ls", "ls",  NULL );
		UNRESOLVED( errno, "Failed to exec" );
	}

	/* Let all processes start and wait for the semaphore */
	sleep( 1 );

	/* Unlink */
	ret = sem_unlink( SEM_NAME );

	if ( ret != 0 )
	{
		UNRESOLVED( errno, "Failed to unlink the semaphore" );
	}

	/* Post the semaphore */
	ret = sem_post( sem );

	if ( ret != 0 )
	{
		UNRESOLVED( errno, "Failed to post the semaphore" );
	}

	/* and close it in this process */
	ret = sem_close( sem );

	if ( ret != 0 )
	{
		UNRESOLVED( errno, "Failed to close the semaphore" );
	}

	/* Wait all processes */
	ctl = waitpid( p1, &status, 0 );

	if ( ctl != p1 )
	{
		UNRESOLVED( errno, "Waitpid returned the wrong PID" );
	}

	if ( ( !WIFEXITED( status ) ) || ( WEXITSTATUS( status ) != 0 ) )
	{
		FAILED( "Child 'sem_close' exited abnormally" );
	}

	ctl = waitpid( p2, &status, 0 );

	if ( ctl != p2 )
	{
		UNRESOLVED( errno, "Waitpid returned the wrong PID" );
	}

	if ( ( !WIFEXITED( status ) ) || ( WEXITSTATUS( status ) != 0 ) )
	{
		FAILED( "Child '_exit' exited abnormally" );
	}

	ctl = waitpid( p3, &status, 0 );

	if ( ctl != p3 )
	{
		UNRESOLVED( errno, "Waitpid returned the wrong PID" );
	}

	if ( ( !WIFEXITED( status ) ) || ( WEXITSTATUS( status ) != 0 ) )
	{
		FAILED( "Child 'exec' exited abnormally" );
	}


	/* Test passed */
#if VERBOSE > 0
	output( "Test passed\n" );

#endif
	PASSED;
}