Motivation:
The documentation for field updates says:
> Note that the guarantees of the {@code compareAndSet}
> method in this class are weaker than in other atomic classes.
> Because this class cannot ensure that all uses of the field
> are appropriate for purposes of atomic access, it can
> guarantee atomicity only with respect to other invocations of
> {@code compareAndSet} and {@code set} on the same updater.
This implies that volatiles shouldn't use normal assignment; the
updater should set them.
Modifications:
Use setter for field updaters that make use of compareAndSet.
Result:
Concurrency compliant code
Motivation:
By STOMP 1.2 specification - header name or value include any octet except CR or LF or ":".
Modification:
Add constructor argument that allows to enable / disable validation.
Result:
Fixes [#7083]
Motivation:
PD and PD0 Both try to find and use Unsafe. If unavailable, they
try to log why and continue on. However, it is not always east to
enable this logging. Chaining exceptions together is much easier
to reach, and the original exception is relevant when Unsafe is
needed.
Modifications:
* Make PD log why PD0 could not be loaded with a trace level log
* Make PD0 remember why Unsafe wasn't available
* Expose unavailability cause through PD for higher level use.
* Make Epoll and KQueue include the reason when failing
Result:
Easier debugging in hard to reconfigure environments
Motivation:
According to SOCKS 5 spec, dstPort = 0 is a valid value in case of UDP ASSOCIATE.
Modifications:
- Allow 0 as port.
- Add unit tests.
Result:
Fixes [#7156].
Motivation:
ServerCookieEncoder’s javadoc contains some invalid copy-pasting from
ClientCookieEncoder.
Modifications:
* As per RFC6265, multiple cookies are sent as separate Set-Cookie
response headers.
* Fix code sample
Result:
Proper javadoc
Motivation:
The decode method is too large to be inlined with default compiler settings, hence the uncommon paths need to be packed and moved away form the common one.
Modifications:
The uncommon paths of the decode call (eg failures with thrown exceptions) are packed and moved in private methods in order to reduce the size of the common one
and let it being inlined.
Result:
The decode method is being inlined if the stack depth allows it.
Motivation:
If AutoClose is false and there is a IoException then AbstractChannel will not close the channel but instead just fail flushed element in the ChannelOutboundBuffer. AbstractChannel also notifies of writability changes, which may lead to an infinite loop if the peer has closed its read side of the socket because we will keep accepting more data but continuously fail because the peer isn't accepting writes.
Modifications:
- If the transport throws on a write we should acknowledge that the output side of the channel has been shutdown and cleanup. If the channel can't accept more data because it is full, and still healthy it is not expected to throw. However if the channel is not healthy it will throw and is not expected to accept any more writes. In this case we should shutdown the output for Channels that support this feature and otherwise just close.
- Connection-less protocols like UDP can remain the same because the channel may disconnected temporarily.
- Make sure AbstractUnsafe#shutdownOutput is called because the shutdown on the socket may throw an exception.
Result:
More correct handling of write failure when AutoClose is false.
Motivation:
ShutdownOutput now fails all pending writes in the ChannelOutboundBuffer and sets it to null. However the Close code path uses the ChannelOutboundBuffer as an indication that the close operation is in progress and exits early and will not call doClose. This will lead to the Channel not actually being fully closed.
Bug introduced by 237a4da1b7
Modifications:
- AbstractChannel#close shouldn't exit early just because outboundBuffer is null, and instead should use additional state closeInitiated to avoid duplicate close operations
Result:
AbstractChannel#close(..) after AbstractChannel#shutdownOutbound() will still invoke doClose and cleanup Channel state.
Motivation:
Netty is unable to use Java9s ALPN support atm.
Modifications:
When running on Java9+ we invoke the correct methods that are exposed on the Java9+ implementation of SSLEngine and so be able to support ALPN.
This patch is based on the work of @rschmitt and so https://github.com/netty/netty/pull/6992.
Result:
Fixes#6933.
Motivation:
netty-tcnative recently change the name of the native libraries from using - to _.
Modifications:
- OpenSsl should use _ instead of - even for the classifiers to be consistent with netty-tcnative
Result:
Loading netty-tcnative works.
Motivation:
We should deprecate ApplicationProtocolNegotiator as the users should use ApplicationProtocolConfig these days.
Modifications:
Add deprecation annotations and javadocs.
Result:
Be able to make package-private in next major release.
Motivation:
We should try to bind to an ipv6 only socket before we enable ipv6 support in the native transport as it may not work due setup of the platform.
Modifications:
Try to bind to ::1 use IPV6 later on if this works
Result:
Fixes [#7021].
Motivation:
Continuing to make netty happy when compiling through errorprone.
Modification:
Mostly comments, some minor switch statement changes.
Result:
No more compiler errors!
Motivation:
When SslHandlerTest#testCompositeBufSizeEstimationGuaranteesSynchronousWrite fails it would be useful to know the SslProvider type
Modifications:
- Print the sever and client SslProvider upon failure
- Increase test timeout to 8 minutes to allow more time to run
Result:
Failures include more info to help diagnose issues.
Motivation:
DnsCache (an interface) is coupled to DnsCacheEntry (a final class). This means that DnsCache implementations can't implement their own DnsCacheEntry objects if the default behavior isn't appropriate.
Modifications:
- DnsCacheEntry should be moved to DefaultDnsCache as it is an implementation detail
- DnsCache#cache(..) should return a new DnsCacheEntry
- The methods which from DnsCacheEntry that were used outside the scope of DefaultDnsCache should be moved into an interface
Result:
DnsCache is more extensible and not tightly coupled to a default implementation of DnsCacheEntry.
Motivation:
DelegatingSslContext at the moment intercept newEngine calls and allow to init the SslEngine after it is created. The problem here is that this may not work the SSLEngine that is wrapped in the SslHandler when calling newHandler(...). This is because some SslContext implementations not delegate to newEngine(...) when creating the SslHandler to allow some optimizations. For this we should also allow to init the SslHandler after its creation and by default just delegate to initEngine(...).
Modifications:
Allow the user to also init the SslHandler after creation while by default init its SSLEngine after creation.
Result:
More flexible and correct code.
Motivation:
Remove Unsafe dependency for Atomic queues in JCTools, resolved in version 2.1.0
Modification:
Change pom JCTools version
Result:
Fixes#7117
Motivation:
As noticed in https://stackoverflow.com/questions/45700277/
compilation can fail if the definition of a method doesn't
match the declaration. It's easy enough to add this in, and make
it easy to compile.
Modifications:
Add JNIEXPORT to the entry points.
* On Windows this adds: `__declspec(dllexport)`
* On Mac this adds: `__attribute__((visibility("default")))`
* On Linux (GCC 4.2+) this adds: ` __attribute__((visibility("default")))`
* On other it doesn't add anything.
Result:
Easier compilation
Motivation:
KQueueEventLoop and EpollEventLoop implement different approaches to applying a timeout of their respective poll calls. Epoll attempts to ensure the desired timeout is satisfied at the java layer and at the JNI layer, but it should be sufficient to account for spurious wakups at the JNI layer. Epoll timeout granularity is also limited to milliseconds which may be too large for some latency sensitive applications.
Modifications:
- Make EpollEventLoop wait method look like KQueueEventLoop
- Epoll should support a finer timeout granularity via timerfd_create. We can hide most of these details behind the epollWait0 JNI call to avoid crossing additional JNI boundaries.
Result:
More consistent timeout approach between KQueue and Epoll.
Motivation:
The EPOLL transport uses EPOLLRDHUP to detect when the peer closes the write side of the socket. Currently KQueue is not able to mimic this behavior and the only way to detect if the peer has closed is to read. It may not always be appropriate to read for backpressure and other reasons at the application level.
Modifications:
- Support EVFILT_SOCK filter which provides notification when the peer closes the socket
Result:
KQueue transport has more consistent behavior with Epoll transport for detecting peer closure.
Motivation:
The construction `new AsciiString(string.substring(...))` can be replaced with the `new AsciiString(string, start, length)` to avoid extra allocation.
Modifications:
Apply the described replacement in `HttpConversionUtil#setHttp2Authority`.
Result:
Less allocations.
Motivation:
- A `hashCode` of the SmtpCommand is recalculated on each call of `hashCode()`. Cached hash code value can be just replaced with call of `name.hashCode()`.
- The commands cache don't work for strings: `SmtpCommand.valueOf("HELO")` returns a new instance.
- Field `contentExpected` is redundant and can be replaced with `equals(DATA)`.
Modifications:
- Use the `name.hashCode()` as hash code result.
- Fix a command cache: use strings as map keys.
- Replace field `contentExpected` to using `this.equals(DATA)`.
- Add unit tests.
Result:
More correct and clean code.
Motivation:
Calling `newInstance()` on a Class object can bypass compile time
checked Exception propagation. This is noted in Java Puzzlers,
as well as in ErrorProne:
http://errorprone.info/bugpattern/ClassNewInstance
Modifications:
Use the niladic constructor to create a new instance.
Result:
Compile time safety for checked exceptions
Motivation:
Due to an oversight (by myself), linking two JNI modules with
duplicate symbols fails in linking. This only seems to happen
some of the time (the behavior seems to be different between GCC
and Clang toolchains). For instance, including both netty tcnative
and netty epoll fails to link because of duplicate JNI_OnLoad
symobols.
Modification:
Do not define the JNI_OnLoad and JNI_OnUnload symbols when
compiling for static linkage, as indicated by the NETTY_BUILD_STATIC
preprocessor define. They are never directly called when
statically linked.
Result:
Able to statically compile epoll and tcnative code into a single
binary.
This reverts commit d63bb4811e as this not covered correctly all cases and so could lead to missing fireChannelReadComplete() calls. We will re-evalute d63bb4811e and resbumit a pr once we are sure all is handled correctly
Motivation:
We recently changed netty-tcnative to use underscores in its native library names.
Modifications:
Update code to use underscores when loading native library.
Result:
More consistent code.
Motivation:
On restricted systems (e.g. grsecurity), it might not be possible to write a .so on disk and load it afterwards. On those system Netty should check java.library.path for libraries to load.
Modifications:
Changed NativeLibraryLoader.java to first try to load libs from java.library.path before exporting the .so to disk.
Result:
Libraries load fine on restricted systems.
Motivation:
SslHandlerTest#testCompositeBufSizeEstimationGuaranteesSynchronousWrite has been observed to fail on CI servers, but it is not clear why.
Modifications:
- Add more visibility into what the state was and what the condition that caused the failure was.
Result:
More visibility when the test fails.
Motivation:
Commit 4448b8f42f introduced some API breakage which we need to revert before we release.
Modifications:
- Introduce an AllocatorAwareSslEngineWrapperFactory which expose an extra method that takes a ByteBufAllocator as well.
- Revert API changes to SslEngineWrapperFactory.
Result:
API breakage reverted.
Motivation:
When compiling this code and running it through errorprone[1], this message appears:
```
StringUtil.java:493: error: [FallThrough] Switch case may fall through; add a `// fall through` comment if it was deliberate
case LINE_FEED:
^
(see http://errorprone.info/bugpattern/FallThrough)
```
By adding that comment, it silences the error and also makes clear the intention of that statement.
[1]http://errorprone.info/index
Modification:
Add simple comment.
Result:
Errorprone is happier with the code.
Motivation:
In ReadOnlyByteBufferBuf.copy(...) we just allocated a ByteBuffer directly and wrapped it. This way it was not possible for us to free the direct memory that was used by the copy without the GC.
Modifications:
- Ensure we use the allocator when create the copy and so be able to release direct memory in a timely manner
- Add unit test
- Depending on if the to be copied buffer is direct or heap based we also allocate the same type on copy.
Result:
Fixes [#7103].
Motivation:
To be able to build with latest java9 release we need to adjust commons-lang version and maven-enforcer-plugin.
Modifications:
- Use commons-lang 2.6.0
- Use maven-enforcer-plugin 3.0.0.M1 when building with java9
Result:
Netty builds again with latest java9 release
Motivation:
`ByteBuf` does not have the little endian variant of float/double access methods.
Modifications:
Add support for little endian floats and doubles into `ByteBuf`.
Result:
`ByteBuf` has get/read/set/writeFloatLE() and get/read/set/writeDoubleLE() methods. Fixes [#6576].
Motivation:
The `AsciiString#toString` method calculate string value and cache it into field. If an `AsciiString` created from the `String` value, we can avoid rebuilding strings if we cache them immediately when creating `AsciiString`. It would be useful for constants strings, which already stored in the JVMs string table, or in cases where an unavoidable `#toString `method call is assumed.
Modifications:
- Add new static method `AsciiString#cache(String)` which save string value into cache field.
- Apply a "benign" data race in the `#hashCode` and `#toString` methods.
Result:
Less memory usage in some `AsciiString` use cases.
Motivation:
At the moment we try to load the library using multiple names which includes names using - but also _ . We should just use _ all the time.
Modifications:
Replace - with _
Result:
Fixes [#7069]
Motivation:
In some cases of using an `InternalThreadLocalMap#stringBuilder`, the `StringBuilder`s size can often exceed the exist limit (1024 bytes). This can lead to permanent memory reallocation.
Modifications:
Add custom properties for the initial capacity and maximum size (after which the `StringBuilder`s capacity will be reduced to the initial capacity).
Result:
An `InternalThreadLocalMap#stringBuilder`s initial and max size is configurable. Fixes [#7092].
Motivation:
SocketStringEchoTest has been observed to fail on CI servers, but the stack traces still indicate work was being done.
Modifications:
- Increase the test timeout
Result:
Tests have more time to complete, and hopefully less false positive test failures.
Motivation:
HttpObjectAggregator differs from HttpServerExpectContinueHandler's handling
of expect headers by not stripping the 'expect' header when a response
is generated.
Modifications:
HttpObjectAggregator now removes the 'expect' header in cases where it generates
a response.
Result:
Consistent and correct behavior between HttpObjectAggregator and HttpServerExpectContinueHandler.
Motivation:
Missing return in ByteBufUtil#writeAscii causes endless loop
Modifications:
Add return after write finished
Result:
ByteBufUtil#writeAscii is ok
Motivation:
We should call promise.setUncancellable() in DefaultHttp2StreamChannel.Unsafe impl to detect if the operation was cancelled.
Modifications:
Add promise.setUncancellable() calls
Result:
More correct handling of cancelled promises
Motivation:
Our http2 child channel implementation was not 100 % complete and had a few bugs. Beside this the performance overhead was non-trivial.
Modifications:
There are a lot of modifications, the most important....
* Http2FrameCodec extends Http2ConnectionHandler and Http2MultiplexCodec extends Http2FrameCodec to reduce performance heads and inter-dependencies on handlers in the pipeline
* Correctly handle outbound flow control for child channels
* Support unknow frame types in Http2FrameCodec and Http2MultiplexCodec
* Use a consistent way how to create Http2ConnectionHandler, Http2FrameCodec and Http2MultiplexCodec (via a builder)
* Remove Http2Codec and Http2CodecBuilder as the user should just use Http2MultipleCodec and Http2MultiplexCodecBuilder now
* Smart handling of flushes from child channels to reduce overhead
* Reduce object allocations
* child channels always use the same EventLoop as the parent Channel to reduce overhead and simplify implementation.
* Not extend AbstractChannel for the child channel implementation to reduce overhead in terms of performance and memory usage
* Remove Http2FrameStream.managedState(...) as the user of the child channel api should just use Channel.attr(...)
Result:
Http2MultiplexCodec (and so child channels) and Http2FrameCodec are more correct, faster and more feature complete.
Motivation:
This PR (unfortunately) does 4 things:
1) Add outbound flow control to the Http2MultiplexCodec:
The HTTP/2 child channel API should interact with HTTP/2 outbound/remote flow control. That is,
if a H2 stream used up all its flow control window, the corresponding child channel should be
marked unwritable and a writability-changed event should be fired. Similarly, a unwritable
child channel should be marked writable and a writability-event should be fired, once a
WINDOW_UPDATE frame has been received. The changes are (mostly) contained in ChannelOutboundBuffer,
AbstractHttp2StreamChannel and Http2MultiplexCodec.
2) Introduce a Http2Stream2 object, that is used instead of stream identifiers on stream frames. A
Http2Stream2 object allows an application to attach state to it, and so a application handler
no longer needs to maintain stream state (i.e. in a map(id -> state)) himself.
3) Remove stream state events, which are no longer necessary due to the introduction of Http2Stream2.
Also those stream state events have been found hard and complex to work with, when porting gRPC
to the Http2FrameCodec.
4) Add support for HTTP/2 frames that have not yet been implemented, like PING and SETTINGS. Also add
a Http2FrameCodecBuilder that exposes options from the Http2ConnectionHandler API that couldn't else
be used with the frame codec, like buffering outbound streams, window update ratio, frame logger, etc.
Modifications:
1) A child channel's writability and a H2 stream's outbound flow control window interact, as described
in the motivation. A channel handler is free to ignore the channel's writability, in which case the
parent channel is reponsible for buffering writes until a WINDOW_UPDATE is received.
The connection-level flow control window is ignored for now. That is, a child channel's writability
is only affected by the stream-level flow control window. So a child channel could be marked writable,
even though the connection-level flow control window is zero.
2) Modify Http2StreamFrame and the Http2FrameCodec to take a Http2Stream2 object intstead of a primitive
integer. Introduce a special Http2ChannelDuplexHandler that has newStream() and forEachActiveStream()
methods. It's recommended for a user to extend from this handler, to use those advanced features.
3) As explained in the documentation, a new inbound stream active can be detected by checking if the
Http2Stream2.managedState() of a Http2HeadersFrame is null. An outbound stream active can be detected
by adding a listener to the ChannelPromise of the write of the first Http2HeadersFrame. A stream
closed event can be listened to by adding a listener to the Http2Stream2.closeFuture().
4) Add a simple Http2FrameCodecBuilder and implement the missing frame types.
Result:
1) The Http2MultiplexCodec supports outbound flow control.
2) The Http2FrameCodec API makes it easy for a user to manage custom stream specific state and to create
new outbound streams.
3) The Http2FrameCodec API is much cleaner and easier to work with. Hacks like the ChannelCarryingHeadersFrame
are no longer necessary.
4) The Http2FrameCodec now also supports PING and SETTINGS frames. The Http2FrameCodecBuilder allows the Http2FrameCodec
to use some of the rich features of the Http2ConnectionHandler API.
Motivation:
EpollDomainSocketGatheringWriteTest. testGatheringWriteBig takes on average about 20-25 seconds on the CI servers, but there is a 30 second timeout being applied which leads to what maybe false positive test failures.
Modifications:
- Increase the test timeout to 120 seconds globally and 60 seconds to wait for all writes per test
Result:
Higher timeout for potentially less false positive test failures.
Motivation:
When using the OIO transport we need to act on byte[] when writing and reading from / to the underyling Socket. So we should ensure we use heap buffers by default to reduce memory copies.
Modifications:
Ensure we prefer heap buffers by default for the OIO transport.
Result:
Possible less memory copies.
Motivation:
SocketGatherWriteTest has been observed to fail and it has numerous issues which when resolved may help reduce the test failures.
Modifications:
- A volatile counter and a spin/sleep loop is used to trigger test termination. Incrementing a volatile is generally bad practice and can be avoided in this situation. This mechanism can be replaced by a promise. This mechanism should also trigger upon exception or channel inactive.
- The TestHandler maintains an internal buffer, but it is not released. We now only create a buffer on the server side and release it after comparing the expected results.
- The composite buffer creation logic can be simplified, also the existing composite buffer doesn't take into account the buffer's reader index when building buf2.
Result:
Cleaner test.
