The library is mostly complete. However, there is some work left
(red = added as a result of the formal
review):
Implement a choice-point-like class, as discussed in
this
thread
Optimize state-entry and state-exit for speed and code-size
Implement simple_state::triggering_event(), which
returns a pointer to the event that triggered the action currently being
executed. This is useful for the rare cases when an entry or exit action
needs to access the event that triggered the execution of the action.
triggering_event() returns a const event_base *
due to the fact that entry and exit actions can be triggered by events of
any type or no event at all
(state_machine<>::initiate() &
state_machine::terminate()). The caller thus needs to make a
type check or cast the return value. The use of
triggering_event() therefore often indicates a problem in
the state machine design and should be avoided whenever possible
Reimplement fifo_scheduler<>::processor_handle so
that fifo_scheduler<>::create_processor<>() and
fifo_scheduler<>::destroy_processor() no longer make
(indirect) calls to global operator new() and operator
delete()
Ensure that everything is compileable with C++ RTTI support turned
off (this requires currently lacking support in Boost.Config and probably
a patch for shared_ptr)
Issue an error if BOOST_STATECHART_USE_NATIVE_RTTI is
defined when C++ RTTI is turned off
The current requirement to pass an mpl::list<> to
specify inner initial states and reactions is too strict. Check the
requirements on the sequences and document them accordingly (David
Abrahams)
Make compilation performance measurements with mpl::vector and
mpl::deque instead of mpl::list to find out which is fastest. Document a
recommendation for the fastest container and change all examples
accordingly (David Abrahams)
Investigate how a state machine could be serialized. A first glance
at the serialization library revealed that there currently (1.33) is no
support for types that overload operator new (suitable code
is already present in the serialization library but it is currently
commented out due to incompatibilities with certain compilers). Such
support would be essential for Boost.Statechart serialization
Implement a switch-like reaction (Simon
Gittins, Darryl Green)
Link incomplete code-snippets in the tutorial to complete example
code where available
Where appropriate, link the reference documentation to examples
Add a description of the implementation and
better explain performance trade-offs (Jonathan Turkanis)
Add links to descriptions of alternate
implementations and discuss performance trade-offs (Jonathan
Turkanis)
Add a list of applications that use
Boost.Statechart (Paul A. Bristow)
Refactor the state_machine class template to reduce code
size in applications with many different state machines
Add a diagram that helps to understand what an unstable state machine
is
Comment MPL-heavy code
Add examples of often made mistakes
Implement priority_scheduler<>
Eliminate code-duplication in fifo_scheduler with PP
code submitted by Pavel Vozenilek
Add number and label to all diagrams in docs
Add #pragma once to all headers (speeds up compilation
with MS-compatible compilers)
Investigate whether and how fifo_worker<> should
accept a policy parameter defining how to lock and wait
Fixed a bug that prevented the use of boost::ref() with
fifo_scheduler<>::create_processor<>, reported by Steve
Hawkes
Fixed bug #3092 (regression test failures in VC10 beta 1), reported by
Richard Webb
1.38.0
Fixed gcc-4.3 warning in state_machine.hpp (ticket #2389), reported by
Bryan Silverthorn
1.36.0
Removed all permanent warning suppressions from library headers
and avoided the resulting warnings with other means (suggested by
Steven Watanabe; thanks to Peter Dimov and Yuval Ronen for insight
into when C4511 & C4512 are issued)
Added defaults for the last two template parameters of in_state_reaction<>
(due to feedback from Sean Kelly)
Adapted fifo_scheduler<> to the changed allocator interface of
boost::function
Changed the PingPong example to demonstrate how the inner workings of
an asynchronous_state_machine<> subclass can be hidden
1.35.0
Added placement new overload to event<> (due to
feedback from Federico J. Fernández)
Made event<> copy-assignable (Federico J.
Fernández)
1.34.0
Fixed a bug that prevented compilation of exception_translator.hpp
(reported by Oliver Kowalke) and adapted TransitionTest.cpp to also test
the exception_translator class
Fixed an allocator-related bug that led to compiler errors in many
tests on GCC >= 4.0
Fixed a number of issues that led to compile-time failures on Intel
9.0 and Code Warrior
Added compile-link tests for all examples
Documented state_machine<>::post_event and added a
const event_base & overload
example/Jamfile.v2 now also stages the dlls necessary to launch the
multithreaded PingPong examples
Added a FAQ item regarding UML2.0 conformance
Made the documentation of unconsumed_event more
visible
Declared state_base::~state_base virtual for GCC. This
makes state exit slightly slower but does away with loads of "has virtual
functions but non-virtual destructor" warnings
Made transitions to history UML2.0 compliant, see here for more information
Fixed a few conformance problems that led to errors on HP compilers
Corrected documentation regarding allocation of states and events
17 December, 2005
Added detailed performance data to the performance document
Added the Performance "example" and the associated Performance.xls,
which were used to perform the more detailed measurements and draw the
associated charts that can now be found in the performance document
Simplified the BitMachine example (the performance measurement
functions are no longer needed)
Removed the to-do item "Investigate how
constant-time dispatch for non-orthogonal state machines can be
implemented" suggested by David Abrahams, Jonathan Turkanis, Rob Steward
and Dave Gomboc. The more detailed performance measurements have shown
that the time spent for event dispatch is almost always small compared to
the time spent for state-entry and state-exit. See Speed versus
scalability tradeoffs in the performance document for more
information
Fixed an order of declaration bug which caused a compile-time error
in event_base.hpp when compiled with GCC3.4.2 on HP-UX (the error neither
showed up on GCC3.4.2 on MinGW nor on MSVC7.1)
Tested with 1.33.1 version of the boost distribution
14 August, 2005
This release will only work with the 1.33.0 version of the boost
distribution
Breaking
change: Added
simple_state<>::operator new &
simple_state<>::operator delete forwarding to the
allocator passed to state_machine (Peter Petrov). This
considerably simplifies memory management customization. A user now only
needs to pass his own allocator to state_machine<> and
no longer has to separately overload operator
new/delete for his state classes. Existing state
classes for which memory management is not customized will thus
automatically use the allocator passed to
state_machine<>. Existing state classes for which
operator new/delete is overloaded
directly will continue to work as before. The only case where
existing code will refuse to compile is when a state class inherits from
an additional base with overloaded operator
new/delete (leading to ambiguous call errors).
Forwarding functions need to be added to such state classes (see
BitMachine for an example)
Breaking change: Added an Allocator parameter to the
event class template and added event<>::operator
new/delete. This makes customizing memory management
easier but could also break existing code (see previous point)
Added Jamfile.v2 files
Added event_base specializations to all reactions and
updated the reference accordingly. This allows to implement reactions
triggered by an event of any type
Added a facility allowing to specially handle events that did not
trigger a reaction. See point 10 of process_event() effects for more
information. Updated tests and docs accordingly
Added a FAQ item explaining how to
trouble-shoot compile-time errors (John Spalding)
Added a FAQ item that presents code for a
StopWatch variant that does not use state-local storage and explains the
drawbacks of that approach (Jeff Garland, Rob Steward)
Added a FAQ item explaining the pitfalls of dynamically linked
state-machines. Also added associated tests to find out whether and how
FSMs can be put into DLLs
Removed the to-do item "Eliminate the need to
wrap a single templated inner initial state into an
mpl::list<>" suggested by Jonathan Turkanis because I
don't currently see how this can be implemented without big ugly
workarounds. A description of the problem can be found here: http://thread.gmane.org/gmane.comp.lib.boost.devel/128741
Put all remarks about code as comments inside
the code (Pavel Vozenilek, Augustus Saunders)
On suitable platforms the library should now be compileable with
exception support turned off (untested due to lacking access to such a
platform)
Added allocator support for broken std libs. Thanks to Joaquín
M López Muñoz for adding his allocator workarounds to
boost/detail
19 June, 2005
Updated the documentation for the new reaction specification
interface
Invalid calls to reaction functions now always
lead to a failing runtime assert (Jonathan Turkanis). In debug mode the
result type is a class with destructive copy semantics,
enabling the detection of a wider range of reaction function abuses.
Added appropriate tests and updated the documentation
Separated performance-related docs from the
rationale into a page of its own (Pavel Vozenilek)
Added clone functionality to events so that
stack-allocated events can now be deferred and posted. Updated the
documentation and tests accordingly (Jonathan Turkanis)
Clarified the definition of context (John
Spalding)
Implemented
in_state_reaction<>. Updated the documentation and
tests accordingly (Darryl Green)
12 May, 2005
Breaking change: Changed the library
namespace from fsm to statechart (Alexander
Nasonov, David Abrahams)
Breaking change: Changed the library
name from boost::fsm to Boost.Statechart (Alexander Nasonov, David
Abrahams)
Breaking change: Reactions are now
specified with a reactions member typedef in a state class
declaration instead of a template parameter (Alexander Nasonov), not yet
documented.
03 May, 2005
Removed the to-do item for the std::type_info
replacement. Thanks to Jody Hagins for taking care of that!
Added to-do items for the issues uncovered during the review
Fixed documentation bugs in the effects descriptions for
state_machine::initiate(),
state_machine::terminate() and
state_machine::process_event()
Moved "Getting started" and "Audience" into
index.html (Augustus Saunders)
Added Basic topics and Intermediate topics
headings and shortened the "How to read this tutorial" section (Augustus
Saunders)
21 February, 2005
Corrected the review period length mentioned above (absolutely no
changes to code and documentation)
20 February, 2005
Breaking change: Incorporated a part of
exception_translator::operator() code into the
state_machine class template. This simplifies custom
exception translators and makes implementing them less error-prone
Breaking change: A request to defer an exception event is no
longer honored and ultimately results in the exception being rethrown.
This change is the result of the rule that during the processing of an
exception no non-user code must be called that could itself propagate an
exception and thus mask the original exception (for event deferral
operator new must be called, which could throw). Exception
event deferral has always been a strange concept anyway
Various code brush-ups
09 February, 2005
Added exception testing to TransitionTest
Fixed a bug that led to an access violation when orthogonal region 0
of a state was terminated before exiting the state (either through
another termination or a transition)
Various minor changes
07 February, 2005
Added FifoSchedulerTest, TerminationTest, CustomReactionTest,
StateIterationTest, TypeInfoTest, StateCastTest, HistoryTest and tests
for inconsistent uses of history, unsupported types of deep history and
invalid statecharts
Fixed a bug that led to a compile-time error when
state_downcast was instantiated with a reference target
Fixed a bug that led to a null function pointer dereference when
history was cleared before making a transition to history
Updated the "Speed versus scalability tradeoffs" section
Fixed previously failing builds of single-threaded variants of the
PingPong example
Moved the "Incompatible compilers" section to index.html
Added explanation for the BitMachine & Handcrafted examples
Various minor changes
25 November, 2004
Adapted to the changes in the 1.32.0 distribution (mainly MPL
changes). The library no longer works with 1.31.0
Fixed a bug that led to a failing runtime assert during state machine
destruction
Fixed a bug that led to events deferred in a composite state not
being released when that state was left
Added TransitionTest and DeferralTest
19 October, 2004
Breaking change: Out of the box, a state machine no longer
uses exception_translator<> to translate exceptions
propagated into the framework. Instead,
null_exception_translator is now used, which does not catch
or translate any exceptions. Updated docs accordingly
Implemented an experimental feature that allows a transition action
to be a member of the transition source or any of its direct or indirect
contexts, see BOOST_STATECHART_RELAX_TRANSITION_CONTEXT
Various small code and documentation improvements
22 May, 2004
Integrated the Intel 7.0 workarounds provided by Pavel Vozenilek
(most are std library workarounds)
Added the Intel 7.0 section to the configuration page
Updated copyright notices
12 May, 2004
Fixed a bug that could have led to an exception_thrown
event being sent to a state that is not the outermost unstable
state in an unstable state machine (as documented in the reference).
Instead, the event was sent to the state where the entry action of a
direct inner state threw an exception, which is only correct for state
machines without orthogonal regions. Also updated the Exception handling section in the
tutorial, which now explains this behavior in detail
Fixed bug that, under extremely rare circumstances, would have
prevented the correct handling of out of memory situations
Fixed an inconsistency in the state entry sequence when a state in an
orthogonal region is the target of a transition originating outside its
direct outer state. Now the states are always entered according to the
number of their orthogonal region, i.e. orthogonal region 0 first, then
orthogonal region 1 and so on. Since the documentation did not define the
sequence (it does now) users should not notice any difference
Changed the implementation of state_machine::terminate()
so that orthogonal regions are now exited strictly from highest to lowest
number instead of arbitrarily as before. Updated docs accordingly
22 April, 2004
Removed the previously added BCC 5.6.4 fixes (the BCC port was
postponed due to lack of knowledge how to work around certain bugs)
Replaced all uses of BOOST_STATIC_CONSTANT with their
mpl counterparts (bool_, integral_c). As a
result, ports to buggy compilers should become easier
Clarified some bits in the tutorial and added StopWatch2.cpp, which
details an alternative way of retrieving state machine state
10 April, 2004
Added two BCC 5.6.4 fixes contributed by Pavel Vozenilek;
Boost.Statechart does not yet work on BCC though
Implemented a few of the documentation and code improvements
suggested by Pavel Vozenilek, including the new "UML to Boost.Statechart
mapping summary" document
26 March, 2004
Fixed a small Intel 8.0 bug in the BitMachine example
25 March, 2004
Now everything compiles warning-free on Intel 8.0
21 March, 2004
Breaking change: fifo_scheduler<> and
fifo_worker<> now always work non-blocking by
default
Added gcc makefiles, contributed by Mitsuo Fukasawa
Breaking change: Added the FifoWorker template
parameter to fifo_scheduler<> and updated
documentation and examples accordingly
13 March, 2004
Breaking change: Renamed worker<> to
fifo_scheduler<> and updated documentation and
examples accordingly
Changed the fifo_scheduler<> implementation so
that a custom worker implementation needs to duplicate less code
Various other small code and doc changes
03 March, 2004
Breaking change: Redesigned the worker<>
and asynchronous_state_machine<> class templates and
updated documentation accordingly. Event processors can now be added and
removed while a worker is running. Moreover, the new design allows for
custom workers with non-FIFO queueing schemes
The StopWatch example now uses std::time() instead of
std::clock()
09 February, 2004
Integrated the standard conformance fixes contributed by Peter
Petrov. The library now also works on GCC 3.2 and should be much easier
to port to other highly conforming compilers
Added the state type information facility to
simple_state
Added the function templates
simple_state::clear_shallow_history() and
simple_state::clear_deep_history()
11 January, 2004
Finished reference documentation
Updated Copyright notices
12 December, 2003
Thanks to Mitsuo Fukasawa the tutorial is now also available in
Japanese!!!
Added a state type information facility
Added reference (unfinished) and configuration documentation and
updated other documents
Various code brush-ups (no breaking changes)
12 October, 2003
Breaking change: Removed rtti_policy<> from
the interface. By default, the library now uses its own (often faster)
RTTI implementation. Users can demand the use of native C++ RTTI by
defining BOOST_STATECHART_USE_NATIVE_RTTI. This change only
affects users who customized state_machine<>,
asynchronous_state_machine<> or
worker<>
Breaking change: Reordered template arguments of
state_machine<> and
asynchronous_state_machine<>. This change only affects
users who customized state_machine<> or
asynchronous_state_machine<>
Added shallow/deep history support and updated documentation
accordingly
Added various compile-time sanity checks
Added 1 FAQ (asked by Mitsuo Fukasawa)
16 August, 2003
Added asynchronous_state_machine<> and
worker<> and updated documentation accordingly
Various minor bug fixes and code improvements (no breaking interface
changes)
Added Keyboard and PingPong examples
Added .pdf documentation
08 June, 2003
Added 3 FAQs (asked by Bohdan) & 1 definition
Removed the superfluous public derivation specifiers in the tutorial
and the examples as suggested by Aleksey Gurtovoy
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