ChangeLog

VERSION 2.3.3:

	Reduced overhead when starting threads.

VERSION 2.3.2:

  License changed to MIT
	
  Bug in non-vanilla AtomicCount implementations corrected. 
	(Caused hanging	in some cases and general trouble with CountedPtr)

  Added configuration option to prefer vanilla implementation where
	possible.

  Fix to Barrier (by Michael Doppler)

	Fix to Thread joining implementation

	Fix to BiasedReadWriteLock

VERSION 2.3.1:

  Bug with PoolExecutor/ConcurrentExecutor not automatically canceling
  themselves properly.
	
VERSION 2.3.0:

  I've been working on some updates after working with Bruce Eckle and
  Chuck Allison; who've provided quite a bit of valuable feedback

  <changes to be enumerted shortly>
	

VERSION 2.2.11:

  Adjusted some of the include files that were missing #include's
  that were left out (Barrier.h, ZThread.h, posix/FastMutex.h)

  Fixed some of the Time class's math.

  FairReadWriteLock should properly release waiters.

  DeferredCancelationScope defers cancelation correctly now
  as it should.

  Started updating the autoconf files, detects asm/atomic.h
  and bits/atomicity.h correctly now.
	
VERSION 2.2.10:

  Rolled up most of the small changes that were available in CVS.
  BlockingQueue was out of date; there was some deadlock potential
  in the Monitor classes that was removed, the AtomicCount needed 
  the dll export decoration, and a few other miscellaneous updates.
	
VERSION 2.2.9:

  Updated ThreadQueue which mistakenly was not removing joined daemon
  threads.

  Updated Win32 SwitchToThread code.
 	 
VERSION 2.2.8:

  Added MacOS support. This has been tested with MacOS X only
	
  Updated BoundedQueue.h
  Updated the vannila primatives

	
VERSION 2.2.7:

  Apply user submitted patch to remove non-nothrow exception specifications. The
  patch can be found (and reversed if desired) in the contrib/ directory
	
  included <assert.h> in Singleton

  Enabled CVS

  Updated read-write lock interface.
    - Dropped RWLock, moved to ReadWriteLock
    - Adjusted implementation of the two concrete subclasses.
	
VERSION 2.2.6:

  Type in FastLock.h fixed.
	
VERSION 2.2.5:

  Added an AtomicCount class that will use as lightwieght a locking mechanism
  as possible. This class is used for limited reference counting and is typically
  not under high contention.
	
VERSION 2.2.4:

  Added mutex implementation for Win32 that will use a normal Mutex object;
  this will perform better under high contention.

  Added a smarter yield function for Win32 implementations; this will kick
  in on NT (or better) and will operate a bit more intelligently than 
  Sleep(0)

  Fixed a typo in LockedQueue
  
  Made Thread::Reference public, most compilers did not complain - gcc 3.0+
  didn't like it private. 

  Renamed ZTHREAD_USE_NATIVE_LOCKS to ZTHREAD_USE_SPIN_LOCKS since that is
  more descriptive of whats going on when that is defined.
	
VERSION 2.2.3:

  Added a ThreadedExecutor.
  Added a template to create Futures. Suggestions to improve the syntax welcome
	
  Fixed some of the compiling errors in the tests & examples I had not
  updated since I made some changes to the library during this last week.

  updated. If you have good examples, or test programs of your own please
  send them to me. I'd like to add some decent examples for using ZThreads but
  I don't have much free time right now.
	
VERSION 2.2.2:

  Added Handle that removes ownership concerns for Runnable objects.
  Thread changed to support it.
	
VERSION 2.2.1:

  Added correct destructor to Queue.

  Changes to the Thread class, this should help eliminate confusion 
  about interruption. (See guide)

  Killing removed, replace with Cancelable semantics that are based
  on interruption. (See guide)
	
  Added a guide for using threads, runnables & interruption
	
  Finished CancelableTask

  Added a guide for using Threads and Runnables to the Thread documentation

  Documentation Updates:

  - Thread
  - CancelableTask

  Removing Future, letting the other changes settle down for a little while,
  while I take time to explore that a little more. 

  Hopefully, the additional documentation is helpful.
	
VERSION 2.2.0:

  *knock, knock, knock* Housekeeping! - Code cleanup, test cases and more 
  documentation. The goal here is to make the basic parts of the library
  independant from the rest, helping to make a more concrete code based to
  build some new abstractions on. 
  
  Cleaning up the dependancies between the various sources, added
  better detection for the implementation selection and simplified whats required
  to build the library in general. This will make it easier to expand on the library
  as a whole, and it will make it easier for others to use in different make utilites.
	
  Decoupled alot of the implementation specific code from the wrappers for the library.

  Added several FastLock implementations and a VannilaRecursiveLock. People adding
  support for (MacOS for example) should have an easy time creating a FastLock, each
  lock uses a different strategy to serialize access, so they should server as a
  nice template. 

  Added test cases for the various primatives ZThreads uses. This helps debugging
  and should help people creating primatives for new platforms.
	
  Adding support for new platforms should be _very_ easy. I will include a guide for 
  how to do this. I've had many requests for MacOS support and for BeOS support, 
  unfortuneatly I don't have a Mac & I don't have time to play with BeOS or Darwin.
  I hope the guide will help some kind soul to contribute the few small classes that
  are required to extend this library to support a few more platforms. OR if you 
  would like to contribute an actual Mac and save yourself some work, that'll work
  for me too - I promise I'll add support to a platform if you give me one :)
	
  Simplified exception classes, helps support error reporting from Futures
  (new feature discussed below)
	
  Cleaned up autoconf scripts, I will probably still maintain VS6 project files
  (eventaully VS7 when I get a computer that handle it, my 2K box is old) but I'm
  trying to move mainly to autoconf.

  * autoconf should be able to use vc to compile & link. I've had moderate success
  (I can compile using msvc with autoconf & cygwin, but have trouble linking)
  it would be nice to have autoconf handle that. I'm looking for help getting that 
  fixed & for getting autoconf to build on cygwin with gcc as well. I don't have
  enough free time to really invesitage that myself.
	
  Changed the semantics of the Condition to make its correct usage clearer.
  Documentation will discuss the changes.

  The library can also be configure through the zthread/Config.h file.

  Remvoed the need for certain objects to be static
	
  -----------------------------------------------------------------------------------

  New things,

  * PriorityMutex, PriorityInheritanceMutex
  * PrioritySemaphore
  * PriorityCondition
  * Barrier (revised)
  * Time
  * Futures 
  * ThreadFactories
  * CancelableTasks
  * Enhanced Executor framework
  * Enhanced ThreadLocals
  * Waitables
	
  Exposed the Time class, which offers relative time values with millsecond
  resolution. 
	
  Added destroyValue() to AbstractThreadLocal, called when a thread that
  has set values on a ThreadLocal is about to exit.

  Improved daemon thread handling. Daemon threads that have compelted can be removed
  sooner. Daemon threads creating other daemon threads will not cause an error.

  Added template methods to Condition that allow a wait on predicate.

  Guard template greatly refined. Quite versitle, I hope to write a short article to
  explain more fully. The syntax is the same, so code using the Guard from previous
  versions should not be affected.

  Synchronization policies deemed uncessarry and removed. It's much better to simply
  parametize the locks, allowing the user specified lock to be the policy. Policies
  are much more awkward than a parametized template for that purpose. This change only
  affects 2 templates.

  TypedLockables not really neccessary w/o syhcronization policies, replaced with the   
  more useful ClassLock that can be used as a parametized type to create a class-wide
  lock. LockableAdpater also removed.
	
  Scraped Observable and Timer classes. Moved the Observable class to the contrib/ 
  directory. It was interesting, but it was not very flexible and surprizingly less
  useful that it seemed. Introduction of the Time class should make it far more 
  effective for people to create thier own Observable classes that will be more 
  robust..
	
  Thread priorities now on by default, and there new PriorityXXX classes
  that take advantage of priorities.

  Dropped SharedInstance support in favor of the SmartPtr. The SmartPointer is 
  really just an example of how something like that can be made with ZThreads.

  Revised the Barrier class to act more like a Barrier should.

  Futures introduced. Future act as a placeholder for a value that may not
  be available yet.

  NullMutex renamed NullLockable to reflect its purpose better.
  SimpleQueue removed, a LockedQueue with a NullLockable is equivalent

  Killed_Exception replaced Unexpected_Exception

  Removed SmartPtr, reverted back just the IntrusivePtr and CountedPtr. Those 
  are simple and are all the library requires. I don't want repeat the work that
  has been done by groups, such as boost, to try and provide a set of smart pointers
  that works across all compilers.

  Executor greatly improved.
	
  -----------------------------------------------------------------------------------

  Documentation Updates:

  - Cancelable
  - Waitable
  - Lockable
  - Time
  - Queues
  - FastMutex, Mutex, PriorityMutex, PriorityInheritanceMutex
  - FastRecursiveMutex, RecursiveMutex
  - Condition, PriorityCondition
  - Semaphore, PrioritySemaphore
  - ThreadLocal
  - Barrier
  - Executor

  Added Design Overview
  Added Porting Guide
  Added Executor Pattern (pending)

  Futures almost complete, still need to update the interruption hooks - I
  made so many changes I wanted to put the new release out and get some 
  feedback.
	
VERSION 2.1.6:

  Maintence to the Mutex, Semaphore & Monitor classes. 
	
VERSION 2.1.5:

  Eliminated race condition when starting daemon threads.

  Removed dllexport/dllimport decorator from some policy classes to 
  avoid unresolved symbol errors when exporting some classes from
  dll on Win32

  Adjusted order of constructors in StaticSingleton so the cleanup
  function doesn't need to be registered with atexit.

  Changed the IntrusivePtr so it works with the Synchronization policies
  provided.

  Added throw() to the destructors of example classes that required it.

  void* _dispatch(void*) moved into namespace ZThread in POSIX_ThreadOps.cc

  explicit typenames added to Observable where required
	
VERSION 2.1.4:

  Refined the Guard template to allow policy to control its behavior keeping the 
  interface compatible with the previous Guard implementation.
  	
  Removed const-ness of the notify method for Observable objects.

  Applied new Guard and policies to Observable, restoring the serialization of the 
  2 argument notify method (fixing the Timer)

  Added policies to Singleton
	
VERSION 2.1.3:
	
  Minor update for win32 build. Just a few adjustments so it build correctly
  under MSVC.

VERSION 2.1.2:

  Unused daemon threads no longer cause assertion failure.
	
  LOCK templates renamed to LockType to avoid collisions with
  LOCK symbols defined in some linux headers.

  Added a TypedLock
  Added ClassLock policy for SmartPtr.
  
  Updated Timer.
	
VERSION 2.1.1:

  Fixed a race condtion in the ConditionImpl.
	
VERSION 2.1.0:

  Updated the autoconf configuration to allow windows or posix version to be
  be selected. 

  Documented all the build flags, see BUILDING
	
  Changes to the implementation to make things more general, robust and easier to
  maintain. 

  Exploring a more tightly synchronized implementation whose logic is
  simpler than the loosely synchronized versions in 2.0.X.

	
VERSION 2.0.5:

  There was an error in the way threads were being started, the parent thread was
  waiting on the childs monitor, which shouldn't happen, and if the child's yeild()
  didn't return control to the parent before the child continued, then deadlock could 
  occur.

  Updated tryAcquire()'s & join() with timeout, to help account for phantom signals
  that could be sent in some circumstances.

  Update the timed wait on ConditionImpl which was erroneously returning true.
	
  My next task is to reevaulate the monitor solution once again and see if there 
  is a way to improve the monitor itself to reduce the complexity of the synchronization
  objects. Probably, using more traditional monitors will be more helpful - the main
  purpose of the new implementation was to join together the logic for the synch objects
  so that future changes could be made more easily.
	
VERSION 2.0.4:

  Added a random stress option that is used to assist in testing the library and
  ensure the 3 basic synchronization objects are correct. It works by
  inserting random sleeps wherever there is a lack of atomicity.

  Fixed the errors made in the synchronization logic in the last release. 
  Fixed a typo resulting from my notoriously bad spelling in Timer.
	
VERSION 2.0.3:

  Updates to Timer.
	
  Updates to ConditionImpl.

VERSION 2.0.2:

  Updates to the some of the #defines for Windows platforms
	
  Updates to the synchronization objects implementation. 
	
  Updated executors docs somewhat, I didn't realize how unclear the documents were
  I wrote them two years ago :)
	
  SynchExecutors will consume tasks now by default, unless you specify otherwise
  using the template parameter. This makes all the Executors behave similarly.
	
VERSION 2.0.1:
	

  Settled on all the changes for the 2.0.X series, this will be the first 
  stable 2.0.X release.

  Removed CheckedMutex, Mutex now throws Deadlock_Exception in order to increase
  usability. 

  The newer monitor implementation for to control the threads & interruption allowed
  me to merge alot more of the code together for the POSIX & WIN32 implementations; 
  which makes this much easier to maintain. Gradually, I'll probably begin to do this 
  will the thread & threadlocal implementations as well.

  This newer implementation also deals with some of the subtle synchronization 
  errors in the 1.0.X version.

  After having learned Win95 does not support the InterlockedComparExchange() function
  an alternate spin lock implementation was added for people who need support on that 
  platform (FastMutex classes).
	
VERSION 2.0.0d:

  Removed the overlapped locks in release(), eliminating that potential deadlock.
	
VERSION 2.0.0c:
	
  Timeouts of 0 are now correctly treated as 0 instead of infinite
  waits.

  Updates for Conditions.
  Fixed all tryAcquire()'s
	
VERSION 2.0.0b:

  Small fix in the Win32 kill(), notify() instead of interrupt(). 

  Custom spin lock was added for the FastMutex & RecursiveFastMutex 
  Win32 implementations - apparently, TryEnterCriticalSection() does
  not work at all on some windows platforms.

  Misc project adjustments, (defines etc).
	
VERSION 2.0.0a:

  POSIX & WIN32 implementations now function quite similarly and will simpler to maintain.

  Revised the primatives for both Win32 & POSIX implementations, check the 
  docs for changes in Mutexes, Conditions & Semaphores. These updates
  address subtle synchronization problems in the original implementation
  as well as usability in general.
	
  Timer values relative to time library loaded, to avoid overflows.

  Reimplemented Threads
	
   join() is interruptable & has optional timeout - see docs	
   kill() is more reliable - see docs
   misc updates that address previous implementations subtle errors
	
  Fixed BlockingQueue cancel() method.
  Fixed ThreadManager sending interrupt() to threads no longer running when
  wantNotify() was true.
	
  Reimplemented ThreadLocals

  More detailed documentation.
	
VERSION 1.5.4:

  Fixed a bug in Win32_MutexImpl.cxx, and Win32_RecursiveMutexImpl.cxx. The waiter lists
  were erroneously decremented in some cases, which caused some mutexes to never
  unlock.
	
  Fixed the subtle race condition in the POSIX_FastRecursiveMutex implementation.
  The power went out for 48 hrs so I was un-busy enough and came up with something
  I think will fix it.

  Updated a documentation error.

  Updated Timer.cxx so that Timer::now() returns more accurate millisecond timing.

  Updated Win32_ThreadManager to be more stlport friendly. 

	
VERSION 1.5.3:

  Fixed a bug in WIN32_ThreadImpl.cxx that caused Thread::sleep() to
  throw Synchronization_Exception instead of Interrupted_Exception.

  Fixed a bug in MonitoredQueue that threq NoSuchElement_Exception 
  rather than Timeout_Exception.

  Fixed POSIX_ThreadImpl.cxx, ThreadImpl::wait(...) The timing for the POSIX
  implementation should be better now. It now spends far less time playing with
  time values so it is more acurate.
	
VERSION 1.5.2:

  Updated executor templates to allow for a little more flexibilty. You can now just plugin
  a new queue or lock implementation rather than having to subclass the AbstractExecutor and
  reimplementing an Exector when all you really neede to change was the queue.
	
  Updated templates to help compilers that were having trouble generating default 
  values for static members.

  Updated time-math in the thread implementation - nanoseconds are measured in billionths
  now as they should be instead of in millionths.

  Added EXTRA_CXXFLAGS and EXTRA_LDFLAGS to the build files so that users can customize
  the build. For example, make "EXTRA_CXXFLAGS=-my-compilers-flags", etc.

  Removed unneccessary 'using namespace std' statements. More friendly for people using 
  various STL implementations which have std::fatal & std::abort defined. That overlap
  caused ambiguity errors when the using statements were present.
	
VERSION 1.5.1:

  Updates to misc. throw() specification errors that some compilers caught
  Small update to Win32 project files
	
VERSION 1.5.0:

  Simplified templates (Executors, etc) avoids multiple definition error when linking
  Timer error fixed  
  Misc bugs (minor) in Win32 implementation repaired.
  Moved old Mutex to PlainMutex, replace with a Mutex that can be interrupted
  which is more useful in general. For most cases the FastMutexes can be used in
  thier place when the user desires no interruption

  Added a couple contributed header for disabling warning with VC, you
  can use them to disable warnings in general for visual c's 
  handling of stl symbols. (optional - vc specific)
	
	
VERSION 1.4.4:

  Fixed bad throw clauses in the examples that gcc 3.0 choked on.
  Updated templates to include a default template with a specialzation for
  daemon threads, resolves alot of problems with compilers generating the 
  code for those tempalte multiple times.
	
VERSION 1.4.4:

  Fixed bad throw clauses in the examples that gcc 3.0 choked on.
  Fixed typo with #ifndef/#define in Win32_FastRecursiveMutex.h
  Corrected documentation for AutoPtr 
  Improved the GNU autoconf/automake builds (again). 
  - Added '--enable-examples' option to configuration
  - Updated configuration files to with libtool 1.4, the older ltconfig
    cause some problems with some systems.
  - Fixed the 'distcheck' rule. 
	
VERSION 1.4.3:	

  Moved the headers to a more standandard directory, everyone asked me
  for it.
	
  Fixed a timeout oversight the ThreadImpl.
  - Blocking with a timeout was not responding correctly.
  - Added one more thread state, JOINING. Prevents multiple joins,
    while allowing the rest of the logic to function correctly.
	
  Improved the GNU autoconf/automake builds. 
  - Added 'make rpm'
  - Added 'make docs'
  - Fixed 'make dist'; previously, I had intended ppl only to use 
    'make' & and 'make install'
  - You learn more about autoconf every time you have to update this
    stuff. Good tool, big learning curve :)
	
VERSION 1.4.2:
	
  Fixed a typo in the AutoPtr class template
	
VERSION 1.4.1:

  Added a pthread.m4 macro, Updaed other misc build files
  Fixed some errors with the throw clauses on Worker & InheritableThreadLocal
  Fixed the Timer class which has been overlooked since the improvements
  to managing static object were made
	
VERSION 1.4.0:

  Make more distinct the change in kill() and other behavoir in the  
  last few version.
	
VERSION 1.3.5:

  Enchanced the ThreadLocal variables.
  Updated & simplified FastMutexs. 
   
VERSION 1.3.4:

	Revised the implementation classes a bit.
	Revised the Worker class so it can be canceled/killed
	without having effects on executing tasks.
	Added new/better support for killing threads
	Added more comments to the implementation classes
	
VERSION 1.3.3:

	Non-realtime thread priorties, prelimary support
	
VERSION 1.3.2:

	Updated subtle bug with threads starting up on some posix
	systems.
	
	Updated errors in the Win32 semaphore classes.
	Updated redudancy is in the POSIX semaphore classes.

	Converted Barrier & Latch to more appropriate template 
	classes
	
VERSION 1.3.1:

	Updated errors in Win32 build files
	Updated the Observable template to be friendly with more compilers
	
VERSION 1.3.0:
	
	Updated compilation bug in Win32 dynamic build. That build will
	compiler correctly again and the dll version will have the same
	behavior as all other builds, making things more predictable.

	Updated executor classes to make room for reusable task objects
	and a little more flexibility

	
VERSION 1.2.4:

	Fixed an oversight in the documentation configuration file and
	the Timer.cxx, I released 1.2.3 just a little too hastily :)
	
VERSION 1.2.3:

	Updated WIN32 & POSIX Thread management
	Bug fix in WIN32 thread wait() routines
	Added daemon thread support for static objects
	
VERSION 1.2.2:

	Factory template added
	Added support for handling static destruction problems

VERSION 1.2.1:

 	Fixed subtle bug in POSIX_ConditionImpl
 	Upated all classes  - misc changes

VERSION 1.2.0:

	Updated much of the implementation classes for the synchronization
	objects. Much faster, and reduced contention.

	Updated the Cancelation interface
	Updated all classes using the Cancalation interface
	
VERSION 1.1.3:

	Spell checked the documents (tedius)

	Bug fix in Barrier.cxx
	Bug fix in WIN32_FastRecursiveMutex.cxx
	Bug fix in WIN32_ConditionImpl.cxx
	
	Cleaned up the System & ThreadImpl interactions
	Cleaned up POSIX & WIN32 ThreadImpl classes

	Updated Documentation (noticable change)
	Updated ThreadLocal classes
	Updated ThreadImpl classes

	Miscellaneuos updates to make some class definitions for
	formal (addition of needed throw() clauses, etc)

	Had some testing on Tru64 unix that was posative
	
VERSION 1.1.2:
	
	Bug fixes in the Thread class. I had overlooked that reference Thread
 	objects (eg from Thread::current()) were deleting the thread implementations
	mistakenly

	Added a very usful Observable template
	Added timer classes

	There might be several other bug fixes I forgot to document completely, most
	of this work was done because I was using Zthreads in creating another application
	so I just fixed and enhanced the library as was appropriate

	Also, there are now static & shared library builds for all supported platforms

VERSION 1.1.1:

	StaticSingletion template was added

	This is another build update, the library will now install
 	so it is much easier to use way.

	Versioned shared libraries were also added using libtool. You
        can link against the shared library, or your can link against
        the .la file in build directory

	A 'zthread-config' script was also added to help other write 
	configure scripts that look for various versions of the library

 
        Some very useful information for the autoconf tools that helped
        can be found at the following URL
      
        http://www.murrayc.com/learning/linux/building_libraries/building_libraries.shtml#RecommendedReading

VERSION 1.1.0-2:
	
	This release basically include some packaging fixes. 
	The autoconf scripts generate Makefiles now that link with
	-pthread instead of -lpthread on FreeBSD

VERSION 1.1.0-1:

	Someone used BoundsChecker and caught a small memory leak
	that was fixed. There was an '==' where a '!=' was needed.
	I wish I could include thier name, but when my university
	email account was closed it ate all my old email so I ended up
	losing that corespondance

VERSION 1.1.0:

	This release has many changes.

	For one, I have tightened up the exception classes. This makes
	the exceptions easier to handle, the code in general, easer to
	read. The exceptions can carry useful information now where as
	before they were just objects of different types being thrown

	Some exceptions have been removed because they were reduntant

	Thread priorites have been remove because I don't feel there is
	a good reason to have them. Thread priorities act differently 
	across all machines, and my goal in creating this library was
	to build a usable archtechure for controlled predicatable 
	multithreading. Thread priorites don't fit in.

	Runnable objects return void now. There is no need to a runnable
	object to return a value. I felt this was an uneeded complexity.
	Enough has been provided in this library to have the results of	
	task run by other threads commincated in a number of better ways
	than a return value.

	A ThreadLocal object was added to provided access to local thread
	storage. This is very much like Java' ThreadLocal object.

	All of the basic synchronization objects have been improved. Several
	new ones have been added whose purposes are straitforward.

	The implementation of the this package was revised and refactored.
	There is no longer a need for a SyncFactory, and a whole layer of 
	virtual function calls was also removed. This increased the speed
	and elegance of the code. The ThreadImpl classes were also better
	encapsulated.

	The Thread class is now extendable and you can use pretty much just
	a like a Java Thread.

	The queue classes have all been updated. I think there may even
	be one more than before. 

	I have refined these queue classes as the executor pattern I was
	using improved. I added a 'Cancelable' interface to these objects
	hopefully I will have the time to write a small paper on the pattern
	to fully explain it. Most of the executor pattern I improved in 
	java and I just recently updated zthreads to reflect this. I may
	relese a java supplement to the library shortly. I find that java 
	is very useful when expirementing with different types of patterns.