gold/gold-threads.cc

   1 // gold-threads.cc -- thread support for gold
   2
   3 // Copyright 2006, 2007 Free Software Foundation, Inc.
   4 // Written by Ian Lance Taylor <iant@google.com>.
   5
   6 // This file is part of gold.
   7
   8 // This program is free software; you can redistribute it and/or modify
   9 // it under the terms of the GNU General Public License as published by
  10 // the Free Software Foundation; either version 3 of the License, or
  11 // (at your option) any later version.
  12
  13 // This program is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 // GNU General Public License for more details.
  17
  18 // You should have received a copy of the GNU General Public License
  19 // along with this program; if not, write to the Free Software
  20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  21 // MA 02110-1301, USA.
  22
  23 #include "gold.h"
  24
  25 #include <cerrno>
  26 #include <cstring>
  27
  28 #ifdef ENABLE_THREADS
  29 #include <pthread.h>
  30 #endif
  31
  32 #include "gold-threads.h"
  33
  34 namespace gold
  35 {
  36
  37 // Class Lock_impl.
  38
  39 class Lock_impl
  40 {
  41  public:
  42   Lock_impl();
  43   ~Lock_impl();
  44
  45   void acquire();
  46
  47   void release();
  48
  49 private:
  50   // This class can not be copied.
  51   Lock_impl(const Lock_impl&);
  52   Lock_impl& operator=(const Lock_impl&);
  53
  54   friend class Condvar_impl;
  55
  56 #ifdef ENABLE_THREADS
  57   pthread_mutex_t mutex_;
  58 #else
  59   bool acquired_;
  60 #endif
  61 };
  62
  63 #ifdef ENABLE_THREADS
  64
  65 Lock_impl::Lock_impl()
  66 {
  67   pthread_mutexattr_t attr;
  68   if (pthread_mutexattr_init(&attr) != 0)
  69     gold_fatal(_("pthead_mutextattr_init failed: %s"), strerror(errno));
  70 #ifdef PTHREAD_MUTEXT_ADAPTIVE_NP
  71   if (pthread_mutextattr_settype(&attr, PTHREAD_MUTEX_ADAPTIVE_NP) != 0)
  72     gold_fatal(_("pthread_mutextattr_settype failed: %s"), strerror(errno));
  73 #endif
  74
  75   if (pthread_mutex_init (&this->mutex_, &attr) != 0)
  76     gold_fatal(_("pthread_mutex_init failed: %s"), strerror(errno));
  77
  78   if (pthread_mutexattr_destroy(&attr) != 0)
  79     gold_fatal(_("pthread_mutexattr_destroy failed: %s"), strerror(errno));
  80 }
  81
  82 Lock_impl::~Lock_impl()
  83 {
  84   if (pthread_mutex_destroy(&this->mutex_) != 0)
  85     gold_fatal(_("pthread_mutex_destroy failed: %s"), strerror(errno));
  86 }
  87
  88 void
  89 Lock_impl::acquire()
  90 {
  91   if (pthread_mutex_lock(&this->mutex_) != 0)
  92     gold_fatal(_("pthread_mutex_lock failed: %s"), strerror(errno));
  93 }
  94
  95 void
  96 Lock_impl::release()
  97 {
  98   if (pthread_mutex_unlock(&this->mutex_) != 0)
  99     gold_fatal(_("pthread_mutex_unlock failed: %s"), strerror(errno));
 100 }
 101
 102 #else // !defined(ENABLE_THREADS)
 103
 104 Lock_impl::Lock_impl()
 105   : acquired_(false)
 106 {
 107 }
 108
 109 Lock_impl::~Lock_impl()
 110 {
 111   gold_assert(!this->acquired_);
 112 }
 113
 114 void
 115 Lock_impl::acquire()
 116 {
 117   gold_assert(!this->acquired_);
 118   this->acquired_ = true;
 119 }
 120
 121 void
 122 Lock_impl::release()
 123 {
 124   gold_assert(this->acquired_);
 125   this->acquired_ = false;
 126 }
 127
 128 #endif // !defined(ENABLE_THREADS)
 129
 130 // Methods for Lock class.
 131
 132 Lock::Lock()
 133 {
 134   this->lock_ = new Lock_impl;
 135 }
 136
 137 Lock::~Lock()
 138 {
 139   delete this->lock_;
 140 }
 141
 142 void
 143 Lock::acquire()
 144 {
 145   this->lock_->acquire();
 146 }
 147
 148 void
 149 Lock::release()
 150 {
 151   this->lock_->release();
 152 }
 153
 154 // Class Condvar_impl.
 155
 156 class Condvar_impl
 157 {
 158  public:
 159   Condvar_impl();
 160   ~Condvar_impl();
 161
 162   void wait(Lock_impl*);
 163   void signal();
 164
 165  private:
 166   // This class can not be copied.
 167   Condvar_impl(const Condvar_impl&);
 168   Condvar_impl& operator=(const Condvar_impl&);
 169
 170 #ifdef ENABLE_THREADS
 171   pthread_cond_t cond_;
 172 #endif
 173 };
 174
 175 #ifdef ENABLE_THREADS
 176
 177 Condvar_impl::Condvar_impl()
 178 {
 179   if (pthread_cond_init(&this->cond_, NULL) != 0)
 180     gold_fatal(_("pthread_cond_init failed: %s"), strerror(errno));
 181 }
 182
 183 Condvar_impl::~Condvar_impl()
 184 {
 185   if (pthread_cond_destroy(&this->cond_) != 0)
 186     gold_fatal(_("pthread_cond_destroy failed: %s"), strerror(errno));
 187 }
 188
 189 void
 190 Condvar_impl::wait(Lock_impl* li)
 191 {
 192   if (pthread_cond_wait(&this->cond_, &li->mutex_) != 0)
 193     gold_fatal(_("pthread_cond_wait failed: %s"), strerror(errno));
 194 }
 195
 196 void
 197 Condvar_impl::signal()
 198 {
 199   if (pthread_cond_signal(&this->cond_) != 0)
 200     gold_fatal(_("pthread_cond_signal failed: %s"), strerror(errno));
 201 }
 202
 203 #else // !defined(ENABLE_THREADS)
 204
 205 Condvar_impl::Condvar_impl()
 206 {
 207 }
 208
 209 Condvar_impl::~Condvar_impl()
 210 {
 211 }
 212
 213 void
 214 Condvar_impl::wait(Lock_impl* li)
 215 {
 216   gold_assert(li->acquired_);
 217 }
 218
 219 void
 220 Condvar_impl::signal()
 221 {
 222 }
 223
 224 #endif // !defined(ENABLE_THREADS)
 225
 226 // Methods for Condvar class.
 227
 228 Condvar::Condvar(Lock& lock)
 229   : lock_(lock)
 230 {
 231   this->condvar_ = new Condvar_impl;
 232 }
 233
 234 Condvar::~Condvar()
 235 {
 236   delete this->condvar_;
 237 }
 238
 239 void
 240 Condvar::wait()
 241 {
 242   this->condvar_->wait(this->lock_.get_impl());
 243 }
 244
 245 void
 246 Condvar::signal()
 247 {
 248   this->condvar_->signal();
 249 }
 250
 251 } // End namespace gold.