Release for 2.5.0 (libplctag#354). Fix libplctag#275. Fix libplctag#338…

…. Fix libplctag#344. Fix libplctag#352.

* Don't call the tag's abort function if it doesn't have one.

* Remove refactored common request status checking code.

* Add common request status checking code.
* Fix duplicate slash in path.

* Bump version for request use-after-free fix.

* callback with user data (libplctag#345)

* add callback with user data

* add test_callback2

* rename plc_tag_register_callback2 to plc_tag_register_callback_ex

* rename test_callback2 to test_callback_ex

* refer to each other

* start fix ups of version.

Co-authored-by: Kyle Hayes <kyle.hayes@gmail.com>

* Break apart the ifdef checks as something in Intellisense is breaking and setting _WIN32 even on Linux.

* Add test_callback_ex to POSIX build.

* Rename string.c to string_standard.c to support better string documentation.

* Fix string docs and examples (libplctag#347)

* Rename string.c to string_standard.c to support better string documentation.

* Split string examples into standard and non-standard.

* Update example docs to describe new string examples.

* Add string tests for standard and UDT strings.

* Fix up extended callback code.   Type of function pointer is not castable to/from a void pointer.  Formatting. (libplctag#348)

* Synthesize create events. (libplctag#349)

* Fix version comment, version 2.5 now.

* Synthesize create events.   Needs to be reworked when event queuing is done.

* Fix event status (libplctag#350)

* Add better (?) status handling for tag events.

* Raise and fire events with new functions.

* Add status output.   Fix required version on test_callback_ex.c.

* More event fixes.   Don't synthesize created event on started events.   Missed special tag created event raise code.

* Add @Joylei's windows event test.

* Change code to use extended callback and only wake one thread instead of all threads.

* Add create callback and fix missing events and duplicate events. (libplctag#351)

* Make mutex locking recursive.

* Raise a read started event when the initial read is triggered.

* Add callback to creation args so that early events can work.

* Fix event handle to avoid duplication, drops and handle early events.

* Clean up example of simple callback.

* Add create callback (libplctag#353)

* Make mutex locking recursive.

* Raise a read started event when the initial read is triggered.

* Add callback to creation args so that early events can work.

* Fix event handle to avoid duplication, drops and handle early events.

* Clean up example of simple callback.

* Add new ignorable directory to .gitignore.

* Remove direct calls to callback function and use raise and dispatch functions.

* DS_Store again.   Where is this coming from?

* Add debugging output of status when raising an event.

* Add casts to force status to correct size.

* Yikes, caught typo of plc_tag_destroy() called instead of plc_tag_decode_error()!

* Wasn't checking for test_callback_ex to exist before running tests.

* Backout change to aid merge.

* Add missing check for test_callback_ex.

* Output status when DELETE event is raised.

* Handle tag deletion events.

Co-authored-by: joylei <leingliu@gmail.com>

Work around git snafu. Can't really delete tags in GitHub?

Merge prerelease with fix libplctag#328. (libplctag#337)

* Adding string test.

* Fix libplctag#328 (libplctag#336)

* Checkin for testing with Valgrind.

* Update string test to catch errors.

* Add overwrite check for string count word.

Merge prerelease with fix libplctag#328. (libplctag#337)

* Adding string test.

* Fix libplctag#328 (libplctag#336)

* Checkin for testing with Valgrind.

* Update string test to catch errors.

* Add overwrite check for string count word.

Prerelease - fixes for Micro8x0 tag listing. (libplctag#335)

* Bump version for more tag listing fixes.

* Allow Omron/Micro8x0 tag listing again.   More fixes.

* More debugging on setting vtable values to determine why raw tags don't work for Micro8x0.

* Split tag listing into Logix and Micro800 code.

* Only output hard errors.

* Update copyright year.

* Fix compile warnings.

* Clean up code.   Make sure callbacks are made for read/write completion.

* Turn into test tool for run_tests.sh.

* Add test_special to test special tags.

* Set up test_tag_attributes as a new test for run_tests.sh.

Merge prerelease, fixes for 100k tags, add tests (libplctag#332)

* Fix libplctag#317 tag list for other plcs (libplctag#318)

* Allow @tags to be created by all CIP PLCs.

* Bump version for Omron/Micro800 tag listing attempt.

* Clean up tag if the returned tag does not have a good status.

* Some PLCs support tag listing but not UDT listing.

* Omron supports request packing.   Omron and Micro800 support tag listing but not UDT listing.

* Omron fixes (libplctag#323)

* Fix indentation.

* Suppress Omron request packing and tag listing.   Not fully supported.

* On use old ForwardOpen on PCCC PLCs.

* Add more tests for PLC-5, Micrologix and DH+ bridging.

* Add test counts, clean up output.

* Exit error codes were swapped.

* Change into a runnable test for the test harness.

* Add more tests and test renaming.

* Automatic read scheduling is not WARN level logging.

* Add random jitter to start of auto reads.

* Abort any in-flight requests when tag is being destroyed.  This will leak otherwise!

* Change how auto read times are handled to prevent temporal clustering.

* Add test_many_tag_perf test program

* New test program to test large numbers of tags using callbacks.

* Commenting out debugging code.

* Wait async for tag creation to complete.

* Still working.   Tried 30 tags.  Need smarter waiting for creation complete.

* Change how tag creation completion is determined based on first read completion.

* Test is now for 100k tags for 30 seconds.  Make this work.

* Fix minor clang warnings. (libplctag#326)

* Fix minor clang warnings.

* Only calculate new auto read time if we triggered a read.  This avoids skips.

* Count start and completion of read/write.

* Small changes to support 100k tags (libplctag#329)

* Add max and average timing for reads.

* Add 100k tag test.

* Update version for new release.

* Lots of tag support (libplctag#330)

* Add max and average timing for reads.

* Add 100k tag test.

* Tweaks for 100k tags.

* Fix logging message.   It is not fatal if we cannot copy the keys.

* Test many tags (libplctag#331)

* Fix logging message.   It is not fatal if we cannot copy the keys.

* Log which port is being opened for the socket.

* Allow the port to be specified.

* Add macOS debugging of socketpair() failure.

* Getting closer, supports 1000 tags well.

* Decrementing ref count could cause the tag to be destroyed, so move it to the end.

* If resource release caused a delete, then the status setting would be a use after free.

* More testing and increase load to 100k tags and 60 seconds.

* Update copyright year.

Fix Omron failures: remove tag listing support and multi-request pack…

…ets. Fix DH+ bridging. (libplctag#325)

* Fix libplctag#317 tag list for other plcs (libplctag#318)

* Allow @tags to be created by all CIP PLCs.

* Bump version for Omron/Micro800 tag listing attempt.

* Clean up tag if the returned tag does not have a good status.

* Some PLCs support tag listing but not UDT listing.

* Omron supports request packing.   Omron and Micro800 support tag listing but not UDT listing.

* Omron fixes (libplctag#323)

* Fix indentation.

* Suppress Omron request packing and tag listing.   Not fully supported.

* On use old ForwardOpen on PCCC PLCs.

* Add more tests for PLC-5, Micrologix and DH+ bridging.

* Add test counts, clean up output.

Fix libplctag#309, Fix libplctag#312, PCCC PLC enhancements (libplcta…

…g#316)

* Bump version for next release.

* Initial add of condition vars to POSIX platform.

* Add initial Windows condition var implementation.

* Need to clear the condition variable flag when leaving wait successfully.

* Add timeout to socket read/write.

* Fix up calls to socket read/write for new timeout parameter.

* Condition variable waits use absolute time, not relative time!

* Complete rewrite of the state machine to use condition vars and socket timeouts.

* Handle socket timeouts.

* Fix up debugging.

* Adding thread_stress to test like async_stress, but multithreaded.

* Clear the tag ID when starting plc_tag_create() as there is no ID at this point.

* Add caller informatio to condition variable functions.

* Clearing the tag ID for debugging happens whether or not the tag is being destroyed.

* Separate out clean up stages for clarity and debugging.

* Change modbus to use fair queuing and fix exposed race condition in run_tags.

Calling rc_dec on the tag could result in the PLC destructor being called but the call to rc_dec is within the PLC mutex.

* Simplify run_tags() tag list handling.

* Added debugging output and fixed compilation warnings on conditional variable functions.

* Added thread_stress.c to Windows build.

* Oops, add the port for the default.

* Add function to clear a condition variable.

Needed for making sure that the cond var is clear before starting to wait for read/write to complete.

* Add constant for the maximum event ID.

* Add condition var to tag.  Add new public functions for waking and base class initialization.

* Whitespace.

* Call base class initialization.

* Call base class initialization.

* Add condition var to session structure.

* Recoding to use condition vars and socket timeouts.

* Comment out timeBeginPeriod() call as it is no longer needed.

The condition variable and socket waits seem to be working well.

* Add time in debugging output.

* Adde thread _stress test.

* On reconnect or initial connect we want to make sure that the session handle is zero.

* Add delay response option to allows test_callback.c to succeed on faster machines.

* Add delay response param to allow callback tests to pass.

* Add response delay in tests for all platforms.

* Bump the delay to 20ms to allow the test to complete correctly.

* Print out milliseconds on timeout failure.

* Set timeout to 50ms to handle really bad CI test VMs.

* Silence warnings about unitialized variables by setting pointers to null.

* Debugging 200 tag stress test results.  PLC overrun?

* Drop log level down to a more reasonable level for production. (libplctag#289)

* Fix libplctag#264 (libplctag#292)

* Change how PCCC/DF1 tag names are parsed to use a struct for the data.

* Add bit tag handling.

* Output which bit is selected on bit tags.

* Tested support for bit tags with N and B files.

* Removing Windows multimedia library since we do not call timeBeginPeriod().

* Support more PCCC data file names (libplctag#296)

* Change PCCC types to be the actual byte type value.  Why translate this?

* Set the element size and type based on the decoding of the PCCC data file name.

* Remove unused commented out code.

* fix incorrect use of address.bit instead of address.is_bit.   Fix type case now that bit is an integer.

* add is_bit flag and bit number.

* Support field names including bits for common data file types.

* Fixed check for single bits.  They are allowed if the element size is 2 bytes.

* Fixed logic on tag timeout.   It was treated as a fatal failure.

* Changed data timeout to 5 seconds.   Network is really bad.

* Support plc_tag_set_debug_level() and change library load path support on Linux. (libplctag#301)

* Hide internal library symbols. (libplctag#302)

* Next version.

* Add modbus test server to test code.

* Add script to run multiple tests.

* Adding macOS ARM binaries to build.  Removed most EXPERIMENTAL names.

* Noting Arm support for macOS.

* Fix 308 - Omron performance (libplctag#313)

* Add more tests for Omron.

* Add Omron support for larger packets and attempt to support Omron strings.

* Fix 312 - add connection grouping. (libplctag#314)

* Add connection group support.

* Fix incorrect checks when searching for an existing Modbus PLC connection.

* Modbus emulator is very slow to start up, add a sleep to wait for it.

* If there is no port open locally, we will get a ECONNREFUSED error.

* Remove duplicate code.

* Merge Modbus perf updates (libplctag#315)

* Initial add of sock_wait_event() and sock_wake().

* Add socket wake pipe constructor.  Need two fds.

* Add start of Windows implementation for socket_wait_event() and socket_wake().

* Disconnect and close are the same event?

* Removed duplicate event type, DISCONNECT vs. CLOSE.

* Move wake pipe creation to first part of connection process instead of doing it on demand.

* Cobble together code to do a wake socket instead of using Windows events.

* Minor compilation fixes.

* Add wrapper function to wake tags.

* Oops, forgot to export plc_tag_generic_wake_tag_impl()!

* Fix typo in debug output.

* Move wake channel set up earlier so that the status does not poison the final return status.

* Move wake channel creation earlier so that the status does not poison the return status.

* Refactor to use socket events.  Basic read and write for single tags works.

* Rework error path clean up of sockets to properly clean up new wake sockets.

* Fix clean up on error path.   Rework receive_response() to lower latency and make sure that we only read exactly the right amount.

* Add new vtable entry for waking the PLC.

* Cleanup some FIXMEs.

* Clean up more FIXMEs.

* Start to include stand enough headers for stand-along compilation.

* Add vtable entry and implementation for waking plc through tag.

* More FIXME cleanups.

* Compilation fixes for socket events.

* Remove unused state enum.

* Try to fix some macOS compilation errors.

* More macOS compilation fixes.

* Set debugging output to debug macOS test failure.

* More macOS.   SIGPIPE suppression is annoying.

* Change to using socketpair() instead of pipe() for better macOS behavior.   MacOS really wants to generate SIGPIPE.

* Removed old, commented out code.

* Clean up calculation of Forward Open packet size.

Fix 312 - add connection grouping. (libplctag#314)

* Add connection group support.

Fix libplctag#295, fix libplctag#306 (libplctag#311)

Fixes issue libplctag#295, timeout not honored when PLC is not connected.  This is particularly problematic on Windows.  This makes the connection process async as well.

Fixes issue libplctag#306, Modbus tags got unequal time.   This changes how Modbus queues work.  

Additional changes:
 - fix output of list_tags so that program tags have the correct full name including the program name.
 - change the socket read/write functions to try doing the socket operation first and only fall back to select() if the operation fails to send/receive data and there is a timeout.  This saves a system call in the common case that data can be written and in the case that a read is broken into multiple calls.