diff options
Diffstat (limited to 'SDL_Core/src/thirdPartyLibs/logger/log4cplus-1.1.0/include/log4cplus/thread/impl/syncprims-pmsm.h')
-rw-r--r-- | SDL_Core/src/thirdPartyLibs/logger/log4cplus-1.1.0/include/log4cplus/thread/impl/syncprims-pmsm.h | 119 |
1 files changed, 119 insertions, 0 deletions
diff --git a/SDL_Core/src/thirdPartyLibs/logger/log4cplus-1.1.0/include/log4cplus/thread/impl/syncprims-pmsm.h b/SDL_Core/src/thirdPartyLibs/logger/log4cplus-1.1.0/include/log4cplus/thread/impl/syncprims-pmsm.h new file mode 100644 index 000000000..f5cd3ef71 --- /dev/null +++ b/SDL_Core/src/thirdPartyLibs/logger/log4cplus-1.1.0/include/log4cplus/thread/impl/syncprims-pmsm.h @@ -0,0 +1,119 @@ +// -*- C++ -*- +// Copyright (C) 2010, Vaclav Haisman. All rights reserved. +// +// Redistribution and use in source and binary forms, with or without modifica- +// tion, 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. +// +// THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, +// INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND +// FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE +// APACHE SOFTWARE FOUNDATION OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, +// INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLU- +// DING, 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. + +//! @file +//! This file contains implementations of reader-writer locking +//! primitive using other primitives, IOW poor man's rwlock. +//! It does not contain any include guards because it is only a fragment +//! to be included by syncprims-{pthreads,win32}.h. + + +#if ! defined (INSIDE_LOG4CPLUS) +# error "This header must not be be used outside log4cplus' implementation files." +#endif + + +// This implements algorithm described in "Concurrent Control with "Readers" +// and "Writers"; P.J. Courtois, F. Heymans, and D.L. Parnas; +// MBLE Research Laboratory; Brussels, Belgium" + + +inline +SharedMutex::SharedMutex () + : m1 (log4cplus::thread::Mutex::DEFAULT) + , m2 (log4cplus::thread::Mutex::DEFAULT) + , m3 (log4cplus::thread::Mutex::DEFAULT) + , w (1, 1) + , writer_count (0) + , r (1, 1) + , reader_count (0) +{ } + + +inline +SharedMutex::~SharedMutex () +{ } + + +inline +void +SharedMutex::rdlock () const +{ + MutexGuard m3_guard (m3); + SemaphoreGuard r_guard (r); + MutexGuard m1_guard (m1); + if (reader_count + 1 == 1) + w.lock (); + + reader_count += 1; +} + + +inline +void +SharedMutex::rdunlock () const +{ + MutexGuard m1_guard (m1); + if (reader_count - 1 == 0) + w.unlock (); + + reader_count -= 1; +} + + +inline +void +SharedMutex::wrlock () const +{ + { + MutexGuard m2_guard (m2); + if (writer_count + 1 == 1) + r.lock (); + + writer_count += 1; + } + try + { + w.lock (); + } + catch (...) + { + MutexGuard m2_guard (m2); + writer_count -= 1; + throw; + } +} + + +inline +void +SharedMutex::wrunlock () const +{ + w.unlock (); + MutexGuard m2_guard (m2); + if (writer_count - 1 == 0) + r.unlock (); + + writer_count -= 1; +} |