Rework the thread utilities so that: We don't pay for a recursive mutex when we don't need the debugging capabilities, a race condition in the reader/writer locks is removed and the interfaces and (still inlined) implementations are separated for improved readability.

This commit is contained in:
Adam Reichold
2016-01-05 23:30:29 +01:00
parent b5aa2dcffc
commit 5883410354
4 changed files with 528 additions and 626 deletions

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@@ -21,7 +21,7 @@ set (BASESOURCEFILES
preferences.cc profilepanel.cc saveasdlg.cc
saveformatpanel.cc soundman.cc splash.cc
thumbnail.cc tonecurve.cc toolbar.cc
guiutils.cc zoompanel.cc toolpanelcoord.cc
guiutils.cc threadutils.cc zoompanel.cc toolpanelcoord.cc
thumbbrowserentrybase.cc batchqueueentry.cc
batchqueue.cc lwbutton.cc lwbuttonset.cc
batchqueuebuttonset.cc browserfilter.cc exiffiltersettings.cc

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@@ -29,11 +29,6 @@
using namespace std;
#if TRACE_MYRWMUTEX==1 && !defined NDEBUG
unsigned int MyReaderLock::readerLockCounter = 0;
unsigned int MyWriterLock::writerLockCounter = 0;
#endif
Glib::RefPtr<Gdk::Pixbuf> MyExpander::inconsistentPBuf;
Glib::RefPtr<Gdk::Pixbuf> MyExpander::enabledPBuf;
Glib::RefPtr<Gdk::Pixbuf> MyExpander::disabledPBuf;

292
rtgui/threadutils.cc Normal file
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@@ -0,0 +1,292 @@
/*
* This file is part of RawTherapee.
*
* Copyright (c) 2016 Adam Reichold <adam.reichold@t-online.de>
*
* RawTherapee is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* RawTherapee is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with RawTherapee. If not, see <http://www.gnu.org/licenses/>.
*/
#include "threadutils.h"
#include <csignal>
#include <iostream>
#ifdef WIN32
#include <windows.h>
#endif
#if STRICT_MUTEX && !NDEBUG
void MyMutex::checkLock ()
{
if (locked) {
std::cerr << "MyMutex already locked!" << std::endl;
#ifdef WIN32
DebugBreak ();
#else
raise (SIGTRAP);
#endif
}
locked = true;
}
void MyMutex::checkUnlock ()
{
if (!locked) {
std::cerr << "MyMutex already unlocked!" << std::endl;
#ifdef WIN32
DebugBreak ();
#else
raise (SIGTRAP);
#endif
}
locked = false;
}
#endif
#if !TRACE_MYRWMUTEX
void MyReaderLock::acquire ()
{
if (locked) {
return;
}
Glib::Threads::Mutex::Lock lock (mutex.mutex);
if (mutex.writerCount == 0) {
// There's no writer operating, we can increment the writer count which will lock writers.
++mutex.writerCount;
} else if (mutex.readerCount == 0) {
// The writer count is non null, but a reader can be the owner of the writer lock,
// which will be the case if the reader count is not zero too.
while (mutex.writerCount != 0) {
mutex.cond.wait(mutex.mutex);
}
// Then, we can increment the writer count.
++mutex.writerCount;
}
// Finally, we can increment the reader count as well.
++mutex.readerCount;
locked = true;
}
void MyReaderLock::release ()
{
if (!locked) {
return;
}
Glib::Threads::Mutex::Lock lock (mutex.mutex);
// decrement the writer number first...
--mutex.readerCount;
if (mutex.readerCount == 0) {
// ...if no more reader, we decrement the writer count as well...
--mutex.writerCount;
// ...and signal the next waiting reader/writer that it's free
mutex.cond.broadcast ();
}
locked = false;
}
void MyWriterLock::acquire ()
{
if (locked) {
return;
}
Glib::Threads::Mutex::Lock lock (mutex.mutex);
// The writer count is not zero, so we have to wait for it to be zero again...
while (mutex.writerCount != 0) {
mutex.cond.wait (mutex.mutex);
}
// ...then we can increment the writer count.
++mutex.writerCount;
locked = true;
}
void MyWriterLock::release ()
{
if (!locked) {
return;
}
Glib::Threads::Mutex::Lock lock (mutex.mutex);
// Decrement the writer number first...
if (--mutex.writerCount == 0) {
// ...and if the writer count is zero again, we can wake up the next writer or reader.
mutex.cond.broadcast ();
}
locked = false;
}
#else
namespace
{
std::ostream& trace (const char* file, int line)
{
const auto currentThread = Glib::Threads::Thread::self ();
return std::cout << currentThread << ":" << file << ":" << line << ": ";
}
}
void MyReaderLock::acquire (const char* file, int line)
{
if (locked) {
trace (file, line) << "MyReaderLock is already locked." << std::endl;
return;
}
trace (file, line) << "Acquiring MyReaderLock..." << std::endl;
Glib::Threads::Mutex::Lock lock (mutex.mutex);
if (mutex.writerCount == 0) {
// There's no writer operating, we can increment the writer count which will lock writers.
++mutex.writerCount;
} else if (mutex.readerCount == 0) {
// The writer count is non null, but a reader can be the owner of the writer lock,
// which will be the case if the reader count is not zero too.
while (mutex.writerCount != 0) {
trace (file, line) << "Waiting for current owner of MyWriterLock..." << std::endl
<< "\tOwner thread: " << mutex.ownerThread << std::endl
<< "\tLast writer file: " << mutex.lastWriterFile << std::endl
<< "\tLast writer line: " << mutex.lastWriterLine << std::endl;
mutex.cond.wait(mutex.mutex);
}
// Then, we can increment the writer count.
++mutex.writerCount;
mutex.ownerThread = Glib::Threads::Thread::self ();
mutex.lastWriterFile = file;
mutex.lastWriterLine = line;
}
// Finally, we can increment the reader count as well.
++mutex.readerCount;
trace (file, line) << "MyReaderLock is now locked, reader count is " << mutex.readerCount << ", writer count is " << mutex.writerCount << "." << std::endl;
locked = true;
}
void MyReaderLock::release (const char* file, int line)
{
if (!locked) {
trace (file, line) << "MyReaderLock is already unlocked." << std::endl;
return;
}
trace (file, line) << "Releasing MyReaderLock..." << std::endl;
Glib::Threads::Mutex::Lock lock (mutex.mutex);
// decrement the writer number first...
--mutex.readerCount;
if (mutex.readerCount == 0) {
// ...if no more reader, we decrement the writer count as well...
--mutex.writerCount;
// ...and signal the next waiting reader/writer that it's free
mutex.cond.broadcast ();
mutex.ownerThread = nullptr;
mutex.lastWriterFile = "";
mutex.lastWriterLine = 0;
}
trace (file, line) << "MyReaderLock is now unlocked, reader count is " << mutex.readerCount << ", writer count is " << mutex.writerCount << "." << std::endl;
locked = false;
}
void MyWriterLock::acquire (const char* file, int line)
{
if (locked) {
trace (file, line) << "MyWriterLock is already locked." << std::endl;
return;
}
trace (file, line) << "Acquiring MyWriterLock..." << std::endl;
Glib::Threads::Mutex::Lock lock (mutex.mutex);
// The writer count is not zero, so we have to wait for it to be zero again...
while (mutex.writerCount != 0) {
trace (file, line) << "Waiting for current owner of MyWriterLock..." << std::endl
<< "\tOwner thread: " << mutex.ownerThread << std::endl
<< "\tLast writer file: " << mutex.lastWriterFile << std::endl
<< "\tLast writer line: " << mutex.lastWriterLine << std::endl;
mutex.cond.wait (mutex.mutex);
}
// ...then we can increment the writer count.
++mutex.writerCount;
mutex.ownerThread = Glib::Threads::Thread::self ();
mutex.lastWriterFile = file;
mutex.lastWriterLine = line;
trace (file, line) << "MyWriterLock is now locked, reader count is " << mutex.readerCount << ", writer count is " << mutex.writerCount << "." << std::endl;
locked = true;
}
void MyWriterLock::release (const char* file, int line)
{
if (!locked) {
trace (file, line) << "MyWriterLock is already unlocked." << std::endl;
return;
}
trace (file, line) << "Releasing MyWriterLock..." << std::endl;
Glib::Threads::Mutex::Lock lock (mutex.mutex);
// Decrement the writer number first...
if (--mutex.writerCount == 0) {
// ...and if the writer count is zero again, we can wake up the next writer or reader.
mutex.cond.broadcast ();
mutex.ownerThread = nullptr;
mutex.lastWriterFile = "";
mutex.lastWriterLine = 0;
}
trace (file, line) << "MyWriterLock is now unlocked, reader count is " << mutex.readerCount << ", writer count is " << mutex.writerCount << "." << std::endl;
locked = false;
}
#endif

View File

@@ -16,30 +16,10 @@
* You should have received a copy of the GNU General Public License
* along with RawTherapee. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef _THREADUTILS_
#define _THREADUTILS_
#include <glibmm.h>
#include <csignal> // for raise()
#include <iostream>
#ifdef WIN32
#include <windows.h>
#endif
#ifdef NDEBUG
// We don't trace mutex
#undef TRACE_MYRWMUTEX
#define TRACE_MYRWMUTEX 0
#endif
// Uncomment this if you want to bypass the CMakeList options and force the values
// Of course, DO NOT COMMIT!
// Uncomment this if you want to bypass the CMakeList options and force the values, but do not commit!
//#undef PROTECT_VECTORS
//#define PROTECT_VECTORS 1
//#undef TRACE_MYRWMUTEX
@@ -47,650 +27,285 @@
//#undef STRICT_MUTEX
//#define STRICT_MUTEX 1
/**
* @brief Custom Mutex to replace Glib::Threads::Mutex, which behave differently on windows (recursive) and linux (non-recursive), by a recursive and "debugable" one
*
* This implementation will behave like a Glib::Threads::RecMutex (STRICT_MUTEX=0) or a Glib::Threads::Mutex (STRICT_MUTEX=1), but in this case, the application will
* crash instead of freezing.
*
* In Debug builds, a printf will let you know that the MyMutex was already locked
*
* The default and recommended mode is STRICT_MUTEX=1
*/
#include <glibmm/threads.h>
#ifdef WIN32
class MyMutex : public Glib::RecMutex
{
#if STRICT_MUTEX && NDEBUG
using MyMutexBase = Glib::Threads::Mutex;
#else
class MyMutex : public Glib::Threads::RecMutex
using MyMutexBase = Glib::Threads::RecMutex;
#endif
/**
* @brief Custom implementation to replace Glib::Threads::Mutex.
*
* Glib::Threads::Mutex shows different behaviour on Windows (recursive) and Linux (non-recursive).
* We therefore use a custom implementation that is optionally recursive and instrumented.
* It will behave like Glib::Threads::RecMutex (STRICT_MUTEX=0) or Glib::Threads::Mutex (STRICT_MUTEX=1).
* Debug builds with strict mutexes, will emit a message and crash immediately upon recursive locking.
*/
class MyMutex : private MyMutexBase
{
#endif
#if STRICT_MUTEX || !defined(NDEBUG)
private:
bool alreadyLocked;
#endif
public:
class MyLock;
#if STRICT_MUTEX || !defined(NDEBUG)
MyMutex() : alreadyLocked(false) {}
#else
MyMutex() {}
#endif
MyMutex () = default;
MyMutex (const MyMutex&) = delete;
MyMutex& operator= (const MyMutex&) = delete;
void lock()
{
#ifdef WIN32
Glib::RecMutex::lock();
#else
Glib::Threads::RecMutex::lock();
#endif
#if STRICT_MUTEX || !defined(NDEBUG)
void lock ();
bool trylock ();
void unlock ();
if (alreadyLocked) {
#ifndef NDEBUG
std::cout << "Warning: MyMutex already locked!" << std::endl; // breakpoint
#if STRICT_MUTEX && !NDEBUG
private:
bool locked = false;
void checkLock ();
void checkUnlock ();
#endif
#if STRICT_MUTEX
#ifndef NDEBUG
#ifdef WIN32
DebugBreak();
#else
raise(SIGTRAP);
#endif
#else
raise(SIGINT);
#endif
#endif
}
alreadyLocked = true;
#endif
}
bool trylock()
{
#ifdef WIN32
if (Glib::RecMutex::trylock())
#else
if (Glib::Threads::RecMutex::trylock())
#endif
{
#if STRICT_MUTEX || !defined(NDEBUG)
if (alreadyLocked) {
#ifndef NDEBUG
std::cout << "Warning: MyMutex already locked!" << std::endl; // breakpoint
#endif
#if STRICT_MUTEX
#ifndef NDEBUG
#ifdef WIN32
DebugBreak();
#else
raise(SIGTRAP);
#endif
#else
raise(SIGINT);
#endif
#endif
}
alreadyLocked = true;
#endif
return true;
}
return false;
}
// Warning: the base class of MyMutex is RecMutex, but the mutex is said "unlocked" on first occurrence of "unlock", to avoid overhead.
void unlock()
{
#if STRICT_MUTEX || !defined(NDEBUG)
alreadyLocked = false;
#endif
#ifdef WIN32
Glib::RecMutex::unlock();
#else
Glib::Threads::RecMutex::unlock();
#endif
}
};
// Class copied from the Glibmm source code, to provide a workaround of the behavior's difference between Linux and Windows
class MyMutex::MyLock
{
public:
explicit inline MyLock(MyMutex& mutex) : mutex_ (mutex), locked_ (true)
{
mutex_.lock();
}
#ifdef WIN32
inline MyLock(MyMutex& mutex, Glib::NotLock) : mutex_ (mutex), locked_ (false) {}
inline MyLock(MyMutex& mutex, Glib::TryLock) : mutex_ (mutex), locked_ (mutex.trylock()) {}
#else
inline MyLock(MyMutex& mutex, Glib::Threads::NotLock) : mutex_ (mutex), locked_ (false) {}
inline MyLock(MyMutex& mutex, Glib::Threads::TryLock) : mutex_ (mutex), locked_ (mutex.trylock()) {}
#endif
inline ~MyLock()
{
if(locked_) {
mutex_.unlock();
}
}
explicit MyLock (MyMutex& mutex);
MyLock (MyMutex& mutex, Glib::Threads::NotLock);
MyLock (MyMutex& mutex, Glib::Threads::TryLock);
inline void acquire()
{
mutex_.lock();
locked_ = true;
}
inline bool try_acquire()
{
locked_ = mutex_.trylock();
return locked_;
}
inline void release()
{
mutex_.unlock();
locked_ = false;
}
inline bool locked() const
{
return locked_;
}
~MyLock ();
MyLock (const MyLock&) = delete;
MyLock& operator= (const MyLock&) = delete;
void acquire ();
bool try_acquire ();
void release ();
private:
MyMutex& mutex_;
bool locked_;
// noncopyable
MyLock(const MyMutex::Lock&);
MyMutex::Lock& operator=(const MyMutex::Lock&);
MyMutex& mutex;
bool locked;
};
/**
* @brief Custom RWLock with debugging feature, to replace the buggy Glib::RWLock (can have negative reader_count value!)
*
* It may be slower, but thread safe!
* @brief Custom implementation to replace Glib::Threads::RWLock
*/
class MyRWMutex
{
public:
#ifdef WIN32
Glib::Mutex handlerMutex; // Having a recursive or non-recursive mutex is not important here, so we can use Glib::Mutex
Glib::Cond access;
#else
Glib::Threads::Mutex handlerMutex; // Having a recursive or non-recursive mutex is not important here, so we can use Glib::Threads::Mutex
Glib::Threads::Cond access;
#endif
size_t writerCount;
size_t readerCount;
#if TRACE_MYRWMUTEX
Glib::ustring lastWriterFile;
int lastWriterLine;
// Unfortunately, ownerThread may not be the culprit of a deadlock, it can be another concurrent Reader...
void* ownerThread;
MyRWMutex () = default;
MyRWMutex (const MyRWMutex&) = delete;
MyRWMutex& operator= (const MyRWMutex&) = delete;
MyRWMutex() : writerCount(0), readerCount(0), lastWriterLine(0), ownerThread(NULL) {}
#else
MyRWMutex() : writerCount(0), readerCount(0) {}
friend class MyReaderLock;
friend class MyWriterLock;
private:
Glib::Threads::Mutex mutex;
Glib::Threads::Cond cond;
std::size_t writerCount = 0;
std::size_t readerCount = 0;
#if TRACE_MYRWMUTEX
Glib::Threads::Thread* ownerThread = nullptr;
const char* lastWriterFile = "";
int lastWriterLine = 0;
#endif
};
/**
* @brief Custom ReaderLock with debugging feature, to replace the buggy Glib::RWLock (can have negative reader_count value!)
*
* @brief Custom implementation to replace Glib::Threads::RWLock::ReaderLock
*/
class MyReaderLock
{
public:
~MyReaderLock ();
MyRWMutex& rwMutex;
MyReaderLock (const MyReaderLock&) = delete;
MyReaderLock& operator= (const MyReaderLock&) = delete;
#if !TRACE_MYRWMUTEX
explicit MyReaderLock (MyRWMutex& mutex);
void acquire ();
void release ();
#else
explicit MyReaderLock (MyRWMutex& mutex, const char* file, int line);
void acquire (const char* file, int line);
void release (const char* file, int line);
#endif
private:
MyRWMutex& mutex;
bool locked;
#if TRACE_MYRWMUTEX
static unsigned int readerLockCounter;
int locknumber;
public:
inline MyReaderLock(MyRWMutex& mutex, const char* name, const char* file, const int line) : rwMutex(mutex), locked(false), locknumber(0)
#else
public:
inline MyReaderLock(MyRWMutex & mutex) : rwMutex(mutex)
#endif
{
// to operate safely
rwMutex.handlerMutex.lock();
#if TRACE_MYRWMUTEX
locknumber = readerLockCounter++;
void* thread = Glib::Thread::self();
std::cout << thread << "/" << locknumber << ":" << name << " / " << file << " : " << line << " - locking - R";
#endif
if (!rwMutex.writerCount) {
// There's no writer operating, we can increment the writer count which will lock writers
++rwMutex.writerCount;
#if TRACE_MYRWMUTEX
std::cout << " ++ new owner";
#endif
} else {
// The writer count is non null, but we can be the owner of the writer lock
// It will be the case if the reader count is non null too.
if (!rwMutex.readerCount) {
// the mutex is in real write mode, we're waiting to see it null
#if TRACE_MYRWMUTEX
std::cout << " waiting..." << std::endl << "Current writer owner: " << rwMutex.lastWriterFile << " : " << rwMutex.lastWriterLine << std::endl;
#endif
while (rwMutex.writerCount) {
rwMutex.access.wait(rwMutex.handlerMutex);
}
++rwMutex.writerCount;
#if TRACE_MYRWMUTEX
rwMutex.lastWriterFile = file;
rwMutex.lastWriterLine = line;
rwMutex.ownerThread = thread;
std::cout << thread << "/" << locknumber << ":" << name << " / " << file << " : " << line << " - locking - R ++ new owner";
#endif
}
}
// then we can increment the reader count
++rwMutex.readerCount;
#if TRACE_MYRWMUTEX
std::cout << " - ReaderCount: " << rwMutex.readerCount << " - WriterCount: " << rwMutex.writerCount << std::endl;
#endif
rwMutex.handlerMutex.unlock();
locked = true;
}
#if TRACE_MYRWMUTEX
// locks the MyRWMutex with Read access if this MyReaderLock has not already locked it, otherwise return safely
inline void acquire(const char* file, const int line)
#else
// locks the MyRWMutex with Read access if this MyReaderLock has not already locked it, otherwise return safely
inline void acquire()
#endif
{
#if TRACE_MYRWMUTEX
void* thread = Glib::Thread::self();
#endif
if (!locked) {
// to operate safely
rwMutex.handlerMutex.lock();
#if TRACE_MYRWMUTEX
std::cout << thread << "/" << locknumber << ":" << file << " : " << line << " - locking - R (lock)";
#endif
if (!rwMutex.writerCount) {
// There's no writer operating, we can increment the writer count which will lock writers
++rwMutex.writerCount;
#if TRACE_MYRWMUTEX
std::cout << " ++ new owner";
#endif
} else {
// The writer count is non null, but a reader can be the owner of the writer lock,
// it will be the case if the reader count is non null too.
if (!rwMutex.readerCount) {
// the mutex is in real write mode, we're waiting to see it null
#if TRACE_MYRWMUTEX
std::cout << " waiting..." << std::endl << "Current writer owner: " << rwMutex.lastWriterFile << " : " << rwMutex.lastWriterLine << std::endl;
#endif
while (rwMutex.writerCount) {
rwMutex.access.wait(rwMutex.handlerMutex);
}
++rwMutex.writerCount;
#if TRACE_MYRWMUTEX
rwMutex.lastWriterFile = file;
rwMutex.lastWriterLine = line;
rwMutex.ownerThread = thread;
std::cout << thread << "/" << locknumber << ":" << file << " : " << line << " - locking - R (lock) ++ new owner";
#endif
}
}
// then we can increment the reader count
++rwMutex.readerCount;
#if TRACE_MYRWMUTEX
std::cout << " - ReaderCount: " << rwMutex.readerCount << " - WriterCount: " << rwMutex.writerCount << std::endl;
#endif
rwMutex.handlerMutex.unlock();
locked = true;
}
#if TRACE_MYRWMUTEX
else {
std::cout << thread << "/" << locknumber << " / already locked by this object - R (lock)" << std::endl;
}
#endif
}
inline ~MyReaderLock()
{
#if TRACE_MYRWMUTEX
void* thread = Glib::Thread::self();
#endif
if (locked) {
// to operate safely
rwMutex.handlerMutex.lock();
// decrement the writer number first
--rwMutex.readerCount;
#if TRACE_MYRWMUTEX
std::cout << thread << "/" << locknumber << " / unlocking - R - ReaderCount: " << rwMutex.readerCount;
#endif
if (!rwMutex.readerCount) {
// no more reader, so we decrement the writer count
--rwMutex.writerCount;
#if TRACE_MYRWMUTEX
rwMutex.lastWriterFile = "";
rwMutex.lastWriterLine = 0;
rwMutex.ownerThread = NULL;
std::cout << " -- new owner possible!" << " >>> ReaderCount: " << rwMutex.readerCount << " - WriterCount: " << rwMutex.writerCount;
#endif
// and signal the next waiting reader/writer that it's free
rwMutex.access.broadcast();
}
#if TRACE_MYRWMUTEX
std::cout << std::endl;
#endif
rwMutex.handlerMutex.unlock();
}
#if TRACE_MYRWMUTEX
else {
std::cout << thread << "/" << locknumber << " / already unlocked by this object - R" << std::endl;
}
#endif
}
#if TRACE_MYRWMUTEX
// releases the MyRWMutex with Write access if this MyWriterLock has already locked it, otherwise return safely
inline void release(const char* file, const int line)
#else
// releases the MyRWMutex with Write access if this MyWriterLock has already locked it, otherwise return safely
inline void release()
#endif
{
#if TRACE_MYRWMUTEX
void* thread = Glib::Thread::self();
#endif
if (locked) {
// to operate safely
rwMutex.handlerMutex.lock();
// decrement the writer number first
--rwMutex.readerCount;
#if TRACE_MYRWMUTEX
std::cout << thread << "/" << locknumber << " / unlocking - R (release) - ReaderCount: " << rwMutex.readerCount;
#endif
if (!rwMutex.readerCount) {
// no more reader, so we decrement the writer count
--rwMutex.writerCount;
#if TRACE_MYRWMUTEX
rwMutex.lastWriterFile = "";
rwMutex.lastWriterLine = 0;
rwMutex.ownerThread = NULL;
std::cout << " -- new owner possible!" << " >>> ReaderCount: " << rwMutex.readerCount << " - WriterCount: " << rwMutex.writerCount;
#endif
// and signal the next waiting reader/writer that it's free
rwMutex.access.broadcast();
}
#if TRACE_MYRWMUTEX
std::cout << std::endl;
#endif
rwMutex.handlerMutex.unlock();
locked = false;
}
#if TRACE_MYRWMUTEX
else {
std::cout << thread << "/" << locknumber << " / already unlocked - R (release)" << std::endl;
}
#endif
}
};
/**
* @brief Custom WriterLock with debugging feature, to replace the buggy Glib::RWLock (can have negative reader_count value!)
*
* @brief Custom implementation to replace Glib::Threads::RWLock::WriterLock
*/
class MyWriterLock
{
public:
~MyWriterLock ();
MyRWMutex& rwMutex;
MyWriterLock (const MyWriterLock&) = delete;
MyWriterLock& operator= (const MyWriterLock&) = delete;
#if !TRACE_MYRWMUTEX
explicit MyWriterLock (MyRWMutex& mutex);
void acquire ();
void release ();
#else
MyWriterLock (MyRWMutex& mutex, const char* file, int line);
void acquire (const char* file, int line);
void release (const char* file, int line);
#endif
private:
MyRWMutex& mutex;
bool locked;
#if TRACE_MYRWMUTEX
static unsigned int writerLockCounter;
int locknumber;
public:
inline MyWriterLock(MyRWMutex& mutex, const char* name, const char* file, const int line) : rwMutex(mutex), locked(false), locknumber(0)
#else
public:
inline MyWriterLock(MyRWMutex & mutex) : rwMutex(mutex)
#endif
{
// to operate safely
rwMutex.handlerMutex.lock();
#if TRACE_MYRWMUTEX
locknumber = writerLockCounter++;
void* thread = Glib::Thread::self();
std::cout << thread << "/" << locknumber << ":" << name << " / " << file << " : " << line << " - locking - W";
#endif
if (rwMutex.writerCount) {
// The writer count is non null, so we have to wait for it to be null again
#if TRACE_MYRWMUTEX
std::cout << " waiting..." << std::endl << "Current writer owner: " << rwMutex.lastWriterFile << " : " << rwMutex.lastWriterLine << std::endl;
#endif
while (rwMutex.writerCount) {
rwMutex.access.wait(rwMutex.handlerMutex);
}
#if TRACE_MYRWMUTEX
std::cout << thread << "/" << locknumber << ":" << file << " : " << line << " - locking - W";
#endif
}
// then we can increment the writer count
++rwMutex.writerCount;
#if TRACE_MYRWMUTEX
rwMutex.lastWriterFile = file;
rwMutex.lastWriterLine = line;
rwMutex.ownerThread = thread;
std::cout << " ++ new owner <<< ReaderCount: " << rwMutex.readerCount << " - WriterCount: " << rwMutex.writerCount << std::endl;
#endif
rwMutex.handlerMutex.unlock();
locked = true;
}
#if TRACE_MYRWMUTEX
// locks the MyRWMutex with Read access if this MyReaderLock has not already locked it, otherwise return safely
inline void acquire(const char* file, const int line)
#else
// locks the MyRWMutex with Read access if this MyReaderLock has not already locked it, otherwise return safely
inline void acquire()
#endif
{
#if TRACE_MYRWMUTEX
void* thread = Glib::Thread::self();
#endif
if (!locked) {
// to operate safely
rwMutex.handlerMutex.lock();
#if TRACE_MYRWMUTEX
std::cout << thread << "/" << locknumber << ":" << file << " : " << line << " - locking - W (lock)";
#endif
if (rwMutex.writerCount) {
// The writer count is non null, so we have to wait for it to be null again
#if TRACE_MYRWMUTEX
std::cout << " waiting..." << std::endl << "Current writer owner: " << rwMutex.lastWriterFile << " : " << rwMutex.lastWriterLine << std::endl;
#endif
while (rwMutex.writerCount) {
rwMutex.access.wait(rwMutex.handlerMutex);
}
#if TRACE_MYRWMUTEX
std::cout << thread << "/" << locknumber << ":" << file << " : " << line << " - locking - W (lock)";
#endif
}
// then we can increment the reader count
++rwMutex.writerCount;
#if TRACE_MYRWMUTEX
rwMutex.lastWriterFile = file;
rwMutex.lastWriterLine = line;
rwMutex.ownerThread = thread;
std::cout << " ++ new owner <<< ReaderCount: " << rwMutex.readerCount << " - WriterCount: " << rwMutex.writerCount << std::endl;
#endif
rwMutex.handlerMutex.unlock();
locked = true;
}
#if TRACE_MYRWMUTEX
else {
std::cout << thread << "/" << locknumber << " / already locked by this object - W (lock)" << std::endl;
}
#endif
}
inline ~MyWriterLock()
{
#if TRACE_MYRWMUTEX
void* thread = Glib::Thread::self();
#endif
if (locked) {
// to operate safely
rwMutex.handlerMutex.lock();
// decrement the writer number first
--rwMutex.writerCount;
#if TRACE_MYRWMUTEX
std::cout << thread << "/" << locknumber << " / unlocking - W";
#endif
if (!rwMutex.writerCount) {
#if TRACE_MYRWMUTEX
rwMutex.lastWriterFile = "";
rwMutex.lastWriterLine = 0;
rwMutex.ownerThread = NULL;
std::cout << " -- new owner possible!";
#endif
// The writer count is null again, so we can wake up the next writer or reader
rwMutex.access.broadcast();
}
#if TRACE_MYRWMUTEX
std::cout << " <<< ReaderCount: " << rwMutex.readerCount << " - WriterCount: " << rwMutex.writerCount << std::endl;
#endif
rwMutex.handlerMutex.unlock();
}
#if TRACE_MYRWMUTEX
else {
std::cout << thread << "/" << locknumber << " / already unlocked by this object - W" << std::endl;
}
#endif
}
#if TRACE_MYRWMUTEX
// releases the MyRWMutex with Write access if this MyWriterLock has already locked it, otherwise return safely
inline void release(const char* file, const int line)
#else
// releases the MyRWMutex with Write access if this MyWriterLock has already locked it, otherwise return safely
inline void release()
#endif
{
#if TRACE_MYRWMUTEX
void* thread = Glib::Thread::self();
#endif
if (locked) {
// to operate safely
rwMutex.handlerMutex.lock();
// decrement the writer number first
--rwMutex.writerCount;
#if TRACE_MYRWMUTEX
std::cout << thread << "/" << locknumber << " / unlocking - W (release)";
#endif
if (!rwMutex.writerCount) {
#if TRACE_MYRWMUTEX
rwMutex.lastWriterFile = "";
rwMutex.lastWriterLine = 0;
rwMutex.ownerThread = NULL;
std::cout << " -- new owner possible!";
#endif
// The writer count is null again, so we can wake up the next writer or reader
rwMutex.access.broadcast();
}
#if TRACE_MYRWMUTEX
std::cout << " <<< ReaderCount: " << rwMutex.readerCount << " - WriterCount: " << rwMutex.writerCount << std::endl;
#endif
rwMutex.handlerMutex.unlock();
locked = false;
}
#if TRACE_MYRWMUTEX
else {
std::cout << thread << "/" << locknumber << " / already unlocked by this object - W (release)" << std::endl;
}
#endif
}
};
inline void MyMutex::lock ()
{
MyMutexBase::lock ();
#if STRICT_MUTEX && !NDEBUG
checkLock ();
#endif
}
inline bool MyMutex::trylock ()
{
if (MyMutexBase::trylock ()) {
#if STRICT_MUTEX && !NDEBUG
checkLock ();
#endif
return true;
}
return false;
}
inline void MyMutex::unlock ()
{
#if STRICT_MUTEX && !NDEBUG
checkUnlock ();
#endif
MyMutexBase::unlock ();
}
inline MyMutex::MyLock::MyLock (MyMutex& mutex)
: mutex (mutex)
, locked (true)
{
mutex.lock();
}
inline MyMutex::MyLock::MyLock (MyMutex& mutex, Glib::Threads::NotLock)
: mutex (mutex)
, locked (false)
{
}
inline MyMutex::MyLock::MyLock (MyMutex& mutex, Glib::Threads::TryLock)
: mutex (mutex)
, locked (mutex.trylock ())
{
}
inline MyMutex::MyLock::~MyLock ()
{
if (locked) {
mutex.unlock ();
}
}
inline void MyMutex::MyLock::acquire ()
{
mutex.lock ();
locked = true;
}
inline bool MyMutex::MyLock::try_acquire ()
{
return locked = mutex.trylock ();
}
inline void MyMutex::MyLock::release ()
{
mutex.unlock ();
locked = false;
}
#if !TRACE_MYRWMUTEX
inline MyReaderLock::MyReaderLock (MyRWMutex& mutex)
: mutex (mutex)
, locked (false)
{
acquire ();
}
inline MyWriterLock::MyWriterLock (MyRWMutex& mutex)
: mutex (mutex)
, locked (false)
{
acquire ();
}
inline MyReaderLock::~MyReaderLock ()
{
if (locked) {
release ();
}
}
inline MyWriterLock::~MyWriterLock ()
{
if (locked) {
release ();
}
}
#else
inline MyReaderLock::MyReaderLock (MyRWMutex& mutex, const char* file, int line)
: mutex (mutex)
, locked (false)
{
acquire (file, line);
}
inline MyWriterLock::MyWriterLock (MyRWMutex& mutex, const char* file, int line)
: mutex (mutex)
, locked (false)
{
acquire (file, line);
}
inline MyReaderLock::~MyReaderLock ()
{
if (locked) {
release (__FILE__, __LINE__);
}
}
inline MyWriterLock::~MyWriterLock ()
{
if (locked) {
release (__FILE__, __LINE__);
}
}
#endif
#if TRACE_MYRWMUTEX
#define MYREADERLOCK(ln, e) MyReaderLock ln(e, #e, __FILE__, __LINE__);
#define MYWRITERLOCK(ln, e) MyWriterLock ln(e, #e, __FILE__, __LINE__);
#define MYREADERLOCK(ln, e) MyReaderLock ln(e, __FILE__, __LINE__);
#define MYWRITERLOCK(ln, e) MyWriterLock ln(e, __FILE__, __LINE__);
#define MYREADERLOCK_ACQUIRE(ln) ln.acquire(__FILE__, __LINE__);
#define MYWRITERLOCK_ACQUIRE(ln) ln.acquire(__FILE__, __LINE__);
#define MYREADERLOCK_RELEASE(ln) ln.release(__FILE__, __LINE__);