1                 : //=============================================================================
       2                 : // File <$/src/cpp/prod/sync/Spin.cpp>
       3                 : // This file is part of YaOrb : Yet Another Object Request Broker,
       4                 : // Copyright (c) 2000-2003, Marc Alff.
       5                 : //
       6                 : // This program is free software; you can redistribute it and/or
       7                 : // modify it under the terms of the GNU General Public License
       8                 : // as published by the Free Software Foundation; either version 2
       9                 : // of the License, or (at your option) any later version.
      10                 : //
      11                 : // This program is distributed in the hope that it will be useful,
      12                 : // but WITHOUT ANY WARRANTY; without even the implied warranty of
      13                 : // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      14                 : // GNU General Public License for more details.
      15                 : //
      16                 : // You should have received a copy of the GNU General Public License
      17                 : // along with this program; if not, write to the Free Software
      18                 : // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
      19                 : //
      20                 : //=============================================================================
      21                 : 
      22                 : // Portability
      23                 : #include "yaorb/config.h"
      24                 : #include "src/cpp/prod/port/port_unistd.h"
      25                 : 
      26                 : #include <asm/bitops.h>
      27                 : #include <iostream>
      28                 : 
      29                 : #include "src/cpp/prod/sync/Spin.h"
      30                 : #include "src/cpp/prod/tool/Assert.h"
      31                 : 
      32                 : // A SPIN is supposed to be locked for a SHORT time.
      33                 : // Complains will be emited every 0.1 second
      34                 : 
      35                 : // FIXME : move to dimensioning.h ? or leave here ...
      36                 : const int UPSET_LIMIT = 100 ;
      37                 : const int USECOND_RETRY_DELAY = 1000 ;
      38                 : 
      39              12 : Spin::Spin()
      40                 :  : _real_spin(0),
      41                 :    _file(),
      42              12 :    _line(0)
      43                 : {
      44              12 :    clear_bit(0, &_real_spin) ;
      45                 : }
      46                 : 
      47               4 : Spin::~Spin()
      48                 : {
      49               8 :    if (test_bit(0, &_real_spin) != 0)
      50                 :    {
      51                 :       std::cerr << "Destroying spin locked by " << _file
      52               0 :          << ", at " << _line << " !" << std::endl ;
      53                 :    }
      54               4 : }
      55                 : 
      56                 : Locker::Locker(
      57                 :    const char* file,
      58                 :    int line,
      59              10 :    Spin& spin)
      60              10 :  : _file(file), _line(line), _spin(spin)
      61                 : {
      62                 :    int lock ;
      63                 :    int count = 0 ;
      64                 : 
      65                 :    do
      66                 :    {
      67              10 :       lock = test_and_set_bit(0, & (_spin._real_spin)) ;
      68                 : 
      69              10 :       if (lock != 0)
      70                 :       {
      71               0 :          count ++ ;
      72                 : 
      73               0 :          if ((count % UPSET_LIMIT) == 0)
      74                 :          {
      75                 :             std::cerr << "Can't get a lock after "
      76               0 :                << count << " attempts !" << std::endl ;
      77                 :             std::cerr << "Locking from " << _file
      78               0 :                << ", at " << _line << "." << std::endl ;
      79                 :             std::cerr << "Spin locked by " << _spin._file 
      80               0 :                << ", at " << _spin._line << "." << std::endl ;
      81                 :          }
      82               0 :          usleep(USECOND_RETRY_DELAY) ;
      83                 :       }
      84                 : 
      85                 :    }
      86                 :    while (lock != 0) ;
      87                 : 
      88              10 :    spin._file = _file ;
      89              10 :    spin._line = _line ;
      90                 : }
      91                 : 
      92              10 : Locker::~Locker()
      93                 : {
      94                 :    ASSERT(_spin._file == _file) ;
      95                 :    ASSERT(_spin._line == _line) ;
      96                 : 
      97                 :    ASSERT(test_bit(0, &(_spin._real_spin)) != 0) ;
      98                 : 
      99              10 :    _spin._file = "" ;
     100              10 :    _spin._line = 0 ;
     101                 : 
     102              10 :    clear_bit(0, & (_spin._real_spin)) ;
     103              49 : }
     104              49 :