libstdc++-v3/testsuite/30_threads/lock/4.cc

   1 // { dg-do run { target *-*-freebsd* *-*-dragonfly* *-*-netbsd* *-*-linux* *-*-gnu* *-*-solaris* *-*-cygwin *-*-rtems* *-*-darwin* powerpc-ibm-aix* } }
   2 // { dg-options "-pthread" { target *-*-freebsd* *-*-dragonfly* *-*-netbsd* *-*-linux* *-*-gnu* *-*-solaris* powerpc-ibm-aix* } }
   3 // { dg-require-effective-target c++11 }
   4 // { dg-require-cstdint "" }
   5 // { dg-require-gthreads "" }
   6
   7 // Copyright (C) 2010-2016 Free Software Foundation, Inc.
   8 //
   9 // This file is part of the GNU ISO C++ Library.  This library is free
  10 // software; you can redistribute it and/or modify it under the
  11 // terms of the GNU General Public License as published by the
  12 // Free Software Foundation; either version 3, or (at your option)
  13 // any later version.
  14
  15 // This library is distributed in the hope that it will be useful,
  16 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 // GNU General Public License for more details.
  19
  20 // You should have received a copy of the GNU General Public License along
  21 // with this library; see the file COPYING3.  If not see
  22 // <http://www.gnu.org/licenses/>.
  23
  24
  25 #include <mutex>
  26 #include <testsuite_hooks.h>
  27
  28 struct unreliable_lock
  29 {
  30   std::mutex m;
  31   std::unique_lock<std::mutex> l;
  32
  33   static int count;
  34   static int throw_on;
  35   static int lock_on;
  36
  37   unreliable_lock() : l(m, std::defer_lock) { }
  38
  39   ~unreliable_lock()
  40   {
  41     bool test __attribute__((unused)) = true;
  42     VERIFY( !l.owns_lock() );
  43   }
  44
  45   void lock()
  46   {
  47     if (count == throw_on)
  48       throw throw_on;
  49     ++count;
  50     l.lock();
  51   }
  52   bool try_lock()
  53   {
  54     if (count == throw_on)
  55       throw throw_on;
  56     std::unique_lock<std::mutex> l2(m, std::defer_lock);
  57     if (count == lock_on)
  58       l2.lock();
  59     ++count;
  60     return l.try_lock();
  61   }
  62
  63   void unlock()
  64   {
  65     bool test __attribute__((unused)) = true;
  66     VERIFY( l.owns_lock() );
  67     l.unlock();
  68   }
  69
  70 };
  71
  72 int unreliable_lock::count = 0;
  73 int unreliable_lock::throw_on = -1;
  74 int unreliable_lock::lock_on = -1;
  75
  76 void test01()
  77 {
  78   bool test __attribute__((unused)) = true;
  79
  80   unreliable_lock l1, l2, l3;
  81
  82   try
  83     {
  84       unreliable_lock::count = 0;
  85       std::lock(l1, l2, l3);
  86       VERIFY( unreliable_lock::count == 3 );
  87       l1.unlock();
  88       l2.unlock();
  89       l3.unlock();
  90     }
  91   catch (...)
  92     {
  93       VERIFY( false );
  94     }
  95 }
  96
  97 void test02()
  98 {
  99   bool test __attribute__((unused)) = true;
 100
 101   // test behaviour when a lock is already held
 102   try
 103     {
 104       unreliable_lock::lock_on = 1;
 105       while (unreliable_lock::lock_on < 3)
 106       {
 107         unreliable_lock::count = 0;
 108         unreliable_lock l1, l2, l3;
 109         std::lock(l1, l2, l3);
 110         VERIFY( unreliable_lock::count > 3 );
 111         l1.unlock();
 112         l2.unlock();
 113         l3.unlock();
 114         ++unreliable_lock::lock_on;
 115       }
 116     }
 117   catch (...)
 118     {
 119       VERIFY( false );
 120     }
 121 }
 122
 123 void test03()
 124 {
 125   // test behaviour when an exception is thrown
 126   unreliable_lock::throw_on = 0;
 127   while (unreliable_lock::throw_on < 3)
 128   {
 129     unreliable_lock::count = 0;
 130     unreliable_lock l1, l2, l3;
 131     bool test = false;
 132     try
 133       {
 134         std::lock(l1, l2, l3);
 135       }
 136     catch (...)
 137       {
 138         test = true;
 139       }
 140     VERIFY( test );
 141     ++unreliable_lock::throw_on;
 142   }
 143 }
 144
 145 int main()
 146 {
 147   test01();
 148   test02();
 149   test03();
 150   return 0;
 151 }