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* fixes #346 nng_recv() sometimes acts on null `msg` pointerGarrett D'Amore2018-04-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | This closes a fundamental flaw in the way aio structures were handled. In paticular, aio expiration could race ahead, and fire before the aio was properly registered by the provider. This ultimately led to the possibility of duplicate completions on the same aio. The solution involved breaking up nni_aio_start into two functions. nni_aio_begin (which can be run outside of external locks) simply validates that nni_aio_fini() has not been called, and clears certain fields in the aio to make it ready for use by the provider. nni_aio_schedule does the work to register the aio with the expiration thread, and should only be called when the aio is actually scheduled for asynchronous completion. nni_aio_schedule_verify does the same thing, but returns NNG_ETIMEDOUT if the aio has a zero length timeout. This change has a small negative performance impact. We have plans to rectify that by converting nni_aio_begin to use a locklesss flag for the aio->a_fini bit. While we were here, we fixed some error paths in the POSIX subsystem, which would have returned incorrect error codes, and we made some optmizations in the message queues to reduce conditionals while holding locks in the hot code path.
* Fix valgrind warning in assert.Garrett D'Amore2018-04-10
| | | | | | | This technically doesn't need the lock, as we're only trying to catch a possible problem during development rather than in the field (and this should never occur), but the false positive in valgrind obscures other possible errors, so leave it in the lock.
* fixes #334 Separate context for state machines from socketsGarrett D'Amore2018-04-10
| | | | | | | | | | | | | | | This provides context support for REQ and REP sockets. More discussion around this is in the issue itself. Optionally we would like to extend this to the surveyor pattern. Note that we specifically do not support pollable descriptors for non-default contexts, and the results of using file descriptors for polling (NNG_OPT_SENDFD and NNG_OPT_RECVFD) is undefined. In the future, it might be nice to figure out how to factor in optional use of a message queue for users who want more buffering, but we think there is little need for this with cooked mode.
* fixes #324 nni_aio_set_synch leads to race conditionGarrett D'Amore2018-04-04
| | | | | | | | fixes #325 synchronous aio completion crash fixes #327 move nni_clock() operations to outside the nni_aio_lk. This work was done for the context tree, and is necessary to properly enable that branch.
* fixes #323 aio's iov may be reusedGarrett D'Amore2018-03-30
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* fixes #316 nni_aio_set_synch() usually doesn't do anythingGarrett D'Amore2018-03-30
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* nng_sleep_aio should honor aio timeout.Garrett D'Amore2018-03-12
| | | | | | | | | | | | | | The first problem was that using nng_sleep_aio was found to reset the timeout, and this caused subsequent operations to start failing with timeouts when reusing the AIO for other operations. The second thing is that we think it would be nicer if the presence of real aio timeouts were still honored, so that if the timeout is shorter than the sleep time, then we get back an NNG_ETIMEDOUT like every other operation, and we get back a 0 if the logical sleep operation completes normally.
* fixes #281 desire nng_sleep_aio()Garrett D'Amore2018-03-12
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* fixes #234 Investigate enabling more verbose compiler warningsGarrett D'Amore2018-02-14
| | | | | | | We enabled verbose compiler warnings, and found a lot of issues. Some of these were even real bugs. As a bonus, we actually save some initialization steps in the compat layer, and avoid passing some variables we don't need.
* fixes #171 Refactor aio to use generic data fieldsGarrett D'Amore2018-02-08
| | | | | | | | This addresses the use of the pipe special field, and eliminates it. The message APIs (recvmsg, sendmsg) need to be updated as well still, but I want to handle that as part of a separate issue. While here we fixed various compiler warnings, etc.
* fixes #228 aio iov should have larger limits (dynamically allocated)Garrett D'Amore2018-02-05
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* fixes #173 Define public HTTP server APIGarrett D'Amore2018-02-01
| | | | | | | | | | | | | | | | | | | | | | | This introduces enough of the HTTP API to support fully server applications, including creation of websocket style protocols, pluggable handlers, and so forth. We have also introduced scatter/gather I/O (rudimentary) for aios, and made other enhancements to the AIO framework. The internals of the AIOs themselves are now fully private, and we have eliminated the aio->a_addr member, with plans to remove the pipe and possibly message members as well. A few other minor issues were found and fixed as well. The HTTP API includes request, response, and connection objects, which can be used with both servers and clients. It also defines the HTTP server and handler objects, which support server applications. Support for client applications will require a client object to be exposed, and that should be happening shortly. None of this is "documented" yet, bug again, we will follow up shortly.
* Expose scatter/gather I/O vectors; we will use for HTTP API.Garrett D'Amore2018-01-29
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* fixes #209 NNG_OPT_TLS_VERIFIED is bustedGarrett D'Amore2018-01-17
| | | | | fixes #210 Want NNG_OPT_TLS_* options for TLS transport fixes #212 Eliminate a_endpt member of aio
* Fix leaks on send.Garrett D'Amore2018-01-03
| | | | | | | I'm pretty sure I need to go back and review the handling of send messages for websocket too. We still have a receive leak in websocket and leaks caused by the new URL parsing code which needs to be refactored.
* fixes #2 Websocket transportGarrett D'Amore2017-12-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a rather large changeset -- it fundamentally adds websocket transport, but as part of this changeset we added a generic framework for both HTTP and websocket. We also made some supporting changes to the core, such as changing the way timeouts work for AIOs and adding additional state keeping for AIOs, and adding a common framework for deferred finalization (to avoid certain kinds of circular deadlocks during resource cleanup). We also invented a new initialization framework so that we can avoid wiring in knowledge about them into the master initialization framework. The HTTP framework is not yet complete, but it is good enough for simple static serving and building additional services on top of -- including websocket. We expect both websocket and HTTP support to evolve considerably, and so these are not part of the public API yet. Property support for the websocket transport (in particular address properties) is still missing, as is support for TLS. The websocket transport here is a bit more robust than the original nanomsg implementation, as it supports multiple sockets listening at the same port sharing the same HTTP server instance, discriminating between them based on URI (and possibly the virtual host). Websocket is enabled by default at present, and work to conditionalize HTTP and websocket further (to minimize bloat) is still pending.
* Improve UDP test coverage, fix numerous issues found.Garrett D'Amore2017-10-05
| | | | | | | | | | | | | | | | We introduced richer, deeper tests for UDP functionality. These tests uncovered a number of issues which this commit fixes. The Windows IOCP code needs to support multiple aios on a single nni_win_event. A redesign of the IOCP handling addresses that. The POSIX UDP code also needed fixes; foremost among them is the fact that the UDP file descriptor is not placed into non-blocking mode, leading to potential hangs. A number of race conditions and bugs along the implementation of the above items were uncovered and fixed. To the best of our knowledge the current code is bug-free.
* All AIOs are initialized. Treat NULL AIOs as noop during stop.Garrett D'Amore2017-09-22
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* Add support for synchronous AIO completions.Garrett D'Amore2017-09-22
| | | | | | | | | We add a flag (auto-clearing) that can be set on an AIO to indicate that the AIO should not processed asynchronously on a taskq. This can be used to enhance performance in some cases, but it can also be used to permit an AIO be destroyed from a completion callback. (For the latter, the callback must execute the new nni_aio_fini_cb() routine, which destroys the AIO without waiting for it to finish.)
* Allocate AIOs dynamically.Garrett D'Amore2017-09-22
| | | | | | | | | | | | | | We allocate AIO structures dynamically, so that we can use them abstractly in more places without inlining them. This will be used for the ZeroTier transport to allow us to create operations consisting of just the AIO. Furthermore, we provide accessors for some of the aio members, in the hopes that we will be able to wrap these for "safe" version of the AIO capability to export to applications, and to protocol and transport implementors. While here we cleaned up the protocol details to use consistently shorter names (no nni_ prefix for static symbols needed), and we also fixed a bug in the surveyor code.
* Endpoint cancellation needs lock protection.Garrett D'Amore2017-08-24
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* Eliminate legacy option settings, provide easier option IDs.Garrett D'Amore2017-08-24
| | | | | | | | | | | | | | | | | | This eliminates all the old #define's or enum values, making all option IDs now totally dynamic, and providing well-known string values for well-behaved applications. We have added tests of some of these options, including lookups, and so forth. We have also fixed a few problems; including at least one crasher bug when the timeouts on reconnect were zero. Protocol specific options are now handled in the protocol. We will be moving the initialization for a few of those well known entities to the protocol startup code, following the PAIRv1 pattern, later. Applications must therefore not depend on the value of the integer IDs, at least until the application has opened a socket of the appropriate type.
* fixes #41 Move DNS out of tcp transportGarrett D'Amore2017-08-21
| | | | | | | | | This moves the DNS related functionality into common code, and also removes all the URL parsing stuff out of the platform specific code and into the transports. Now the transports just take sockaddr's on initialization. (We may want to move this until later.) We also add UDP resolution as another separate API.
* Provide versions of mutex, condvar, and aio init that never fail.Garrett D'Amore2017-08-16
| | | | | | | | | | | | | | | | | | | | | | | If the underlying platform fails (FreeBSD is the only one I'm aware of that does this!), we use a global lock or condition variable instead. This means that our lock initializers never ever fail. Probably we could eliminate most of this for Linux and Darwin, since on those platforms, mutex and condvar initialization reasonably never fails. Initial benchmarks show little difference either way -- so we can revisit (optimize) later. This removes a lot of otherwise untested code in error cases and so forth, improving coverage and resilience in the face of allocation failures. Platforms other than POSIX should follow a similar pattern if they need this. (VxWorks, I'm thinking of you.) Most sane platforms won't have an issue here, since normally these initializations do not need to allocate memory. (Reportedly, even FreeBSD has plans to "fix" this in libthr2.) While here, some bugs were fixed in initialization & teardown. The fallback code is properly tested with dedicated test cases.
* Thundering herd kills performance.Garrett D'Amore2017-08-10
| | | | | | | | | | | | | | A little benchmarking showed that we were encountering far too many wakeups, leading to severe performance degradation; we had a bunch of threads all sleeping on the same condition variable (taskqs) and this woke them all up, resulting in heavy mutex contention. Since we only need one of the threads to wake, and we don't care which one, let's just wake only one. This reduced RTT latency from about 240 us down to about 30 s. (1/8 of the former cost.) There's still a bunch of tuning to do; performance remains worse than we would like.
* Don't clear the AIO provider data in finish.Garrett D'Amore2017-08-07
| | | | | | The finish routine can race against an asynchronous cancellation, so we must not clear the data pointer, or we can wind up with a NULL pointer dereference.
* Subsystem initialize is idempotent; simplify cleanup.Garrett D'Amore2017-08-07
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* Refactor AIO logic to close numerous races and reduce complexity.Garrett D'Amore2017-08-04
| | | | | | | | | This passes valgrind 100% clean for both helgrind and deep leak checks. This represents a complete rethink of how the AIOs work, and much simpler synchronization; the provider API is a bit simpler to boot, as a number of failure modes have been simply eliminated. While here a few other minor bugs were squashed.
* Eliminate the separate AIO wake callback, making nni_aio_waitGarrett D'Amore2017-07-21
| | | | block for any AIO completion.
* Simpler taskq API.Garrett D'Amore2017-07-21
| | | | | | | The queue is bound at initialization time of the task, and we call entries just tasks, so we don't have to pass around a taskq pointer across all the calls. Further, nni_task_dispatch is now guaranteed to succeed.
* Yet more race condition fixes.Garrett D'Amore2017-07-20
| | | | | | | | | We need to remember that protocol stops can run synchronously, and therefore we need to wait for the aio to complete. Further, we need to break apart shutting down aio activity from deallocation, as we need to shut down *all* async activity before deallocating *anything*. Noticed that we had a pipe race in the surveyor pattern too.
* Always run the AIO completion logic.Garrett D'Amore2017-07-19
| | | | | | | | We have seen some yet another weird situation where we had an orphaned pipe, which was caused by not completing the callback. If we are going to run nni_aio_fini, we should still run the callback (albeit with a return value of NNG_ECANCELED or somesuch) to be sure that we can't orphan stuff.
* Fixes most of the raaces in posix; but at least one remains outstanding.Garrett D'Amore2017-07-18
| | | | | | Apparently there are circumstances when a pipedesc may get orphaned form the pollq. This triggers an assertion failure when it occurs. I am still trying to understand how this can occur. Stay tuned.
* Sometimes providers don't clear the prov data details. (Backoff).Garrett D'Amore2017-07-18
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* Fix close-related leak of pipes.Garrett D'Amore2017-07-18
| | | | | | | | | | | We have seen leaks of pipes causing test failures (e.g. the Windows IPC test) due to EADDRINUSE. This was caused by a case where we failed to pass the pipe up because the AIO had already been canceled, and we didn't realize that we had oprhaned the pipe. The fix is to add a return value to nni_aio_finish, and verify that we did finish properly, or if we did not then we must free the pipe ourself. (The zero return from nni_aio_finish indicates that it accepts ownership of resources passed via the aio.)
* AIO timeouts work correctly now, using their own timer logic.Garrett D'Amore2017-07-16
| | | | | | | | We closed a few subtle races in the AIO subsystem as well, and now we were able to eliminate the separate timer handling the MQ code. There appear to be some opportunities to further enhance the code for MQs as well -- eventually probably the only access to MQs will be with AIOs.
* Race conditions removed... TCP tests work well know.Garrett D'Amore2017-07-15
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* Give up on uncrustify; switch to clang-format.Garrett D'Amore2017-07-10
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* Fixes for async resolver, plus a test suite for it.Garrett D'Amore2017-07-06
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* Improved routines for list management.Garrett D'Amore2017-07-04
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* inproc transport uses aio for connect/accept.Garrett D'Amore2017-07-03
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* Pass cancel of IPC and TCP all the way down to POSIX pipedescs.Garrett D'Amore2017-06-29
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* Refactor stop again, closing numerous races (thanks valgrind!)Garrett D'Amore2017-06-28
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* Fix taskq_cancel race.Garrett D'Amore2017-06-08
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* Start of close related race fixes. Scalability test.Garrett D'Amore2017-03-10
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* Pipeline protocol now entirely callback driven.Garrett D'Amore2017-03-04
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* Timer implementation. Operations can timeout now?Garrett D'Amore2017-03-03
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* Start of msgq aio.Garrett D'Amore2017-03-01
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* Rename ioev to aio. Eliminate generic cancel handling (not needed).Garrett D'Amore2017-02-23
We will still need some kind of specific handling of cancellation for msg queues, but it will be simpler to just implement that for the queues, and not worry about cancellation in the general case around poll etc. (The low level poll and I/O routines will get notified by their underlying transport pipes/descriptors closing.)