/* lockut.c: LOCK UTILIZATION TEST
 *
 * $Id$
 * Copyright (c) 2001-2014 Ravenbrook Limited.  See end of file for license.
 */

#include "mpm.h"
#include "testlib.h"
#include "testthr.h"

#include <stdio.h> /* printf */
#include <stdlib.h> /* malloc */


#define nTHREADS 4

static Lock lock;
unsigned long shared, tmp;


static void incR(unsigned long i)
{
  LockClaimRecursive(lock);
  if (i < 100) {
    while(i--) {
      tmp = shared;
      shared = tmp + 1;
    }
  } else {
    incR(i >> 1);
    incR( (i+1) >> 1);
  }
  LockReleaseRecursive(lock);
}


static void inc(unsigned long i)
{
  incR( (i+1) >>1);
  i >>= 1;
  while (i) {
    LockClaim(lock);
    if (i > 10000) {
      incR(5000);
      i -= 5000;
    }
    tmp = shared;
    shared = tmp+1;
    i--;
    LockReleaseMPM(lock);
  }
}


#define COUNT 100000l
static void *thread0(void *p)
{
  testlib_unused(p);
  inc(COUNT);
  return NULL;
}


int main(int argc, char *argv[])
{
  testthr_t t[10];
  unsigned i;

  testlib_init(argc, argv);

  lock = malloc(LockSize());
  Insist(lock != NULL);

  LockInit(lock);
  UNUSED(argc);

  shared = 0;

  for(i = 0; i < nTHREADS; i++)
    testthr_create(&t[i], thread0, NULL);

  for(i = 0; i < nTHREADS; i++)
    testthr_join(&t[i], NULL);

  Insist(shared == nTHREADS*COUNT);

  LockFinish(lock);

  printf("%s: Conclusion: Failed to find any defects.\n", argv[0]);
  return 0;
}


/* C. COPYRIGHT AND LICENSE
 *
 * Copyright (c) 2001-2014 Ravenbrook Limited <http://www.ravenbrook.com/>.
 * All rights reserved.  This is an open source license.  Contact
 * Ravenbrook for commercial licensing options.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 * 
 * 1. Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 * 
 * 3. Redistributions in any form must be accompanied by information on how
 * to obtain complete source code for this software and any accompanying
 * software that uses this software.  The source code must either be
 * included in the distribution or be available for no more than the cost
 * of distribution plus a nominal fee, and must be freely redistributable
 * under reasonable conditions.  For an executable file, complete source
 * code means the source code for all modules it contains. It does not
 * include source code for modules or files that typically accompany the
 * major components of the operating system on which the executable file
 * runs.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
 * PURPOSE, OR NON-INFRINGEMENT, ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT HOLDERS AND CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */