Motivation:
The behaviour of the FixedChannelPool.release was inconsistent with the
SimpleChannelPool implementation, in that given promise is returned.
In the FixedChannelPool implementation a new promise was return and
this meant that the completion of that promise can be different.
Specifically on releasing a channel to a closed pool, the parameter
promise is failed with an IllegalStateException but the returned one
will have been successful (as it was completed by call to super
.release)
Modification:
Return the given promise as the result of FixedChannelPool.release
Result:
Returned promise will reflect the result of the release operation.
Motivation:
Channels returned to a FixedChannelPool after closing it remain active.
Since channels that where acquired from the pool are not closed during the close operation, they remain open even after releasing the channel back to the pool where they are then in accessible and become in-effect a connection leak.
Modification:
Close the released channel on releasing back to a closed pool.
Result:
Much harder to create a connection leak by closing an active
FixedChannelPool instance.
Motivation:
We should not fail the promise when a closed Channel is offereed back to the ChannelPool as we explicit mention that the Channel must always be returned.
Modifications:
- Not fail the promise
- Add test-case
Result:
Fixes [#6831]
Motivation:
ChannelPipeline will happily add a handler to a closed Channel's pipeline and will call handlerAdded(...) but will not call handlerRemoved(...).
Modifications:
Check if pipeline was destroyed and if so not add the handler at all but propergate an exception.
Result:
Fixes [#6768]
Motivation:
We currently don't have a native transport which supports kqueue https://www.freebsd.org/cgi/man.cgi?query=kqueue&sektion=2. This can be useful for BSD systems such as MacOS to take advantage of native features, and provide feature parity with the Linux native transport.
Modifications:
- Make a new transport-native-unix-common module with all the java classes and JNI code for generic unix items. This module will build a static library for each unix platform, and included in the dynamic libraries used for JNI (e.g. transport-native-epoll, and eventually kqueue).
- Make a new transport-native-unix-common-tests module where the tests for the transport-native-unix-common module will live. This is so each unix platform can inherit from these test and ensure they pass.
- Add a new transport-native-kqueue module which uses JNI to directly interact with kqueue
Result:
JNI support for kqueue.
Fixes https://github.com/netty/netty/issues/2448
Fixes https://github.com/netty/netty/issues/4231
This fixes#6652.
Rationale
The invocation of initChannel of ChannelInitializer has been moved to as
early as during handlerAdded is invoked in 26aa34853, whereas it was
only invoked during channelRegistered is invoked before that. So the
comment does not describe how handlers are added in normal circumstances
anymore.
However, the code is kept as-is since there might be unusual cases, and
adding ServerBootstrapAcceptor via the event loop is always safe to
enforce the correct order.
Motivation:
In cases when an application is running in a container or is otherwise
constrained to the number of processors that it is using, the JVM
invocation Runtime#availableProcessors will not return the constrained
value but rather the number of processors available to the virtual
machine. Netty uses this number in sizing various resources.
Additionally, some applications will constrain the number of threads
that they are using independenly of the number of processors available
on the system. Thus, applications should have a way to globally
configure the number of processors.
Modifications:
Rather than invoking Runtime#availableProcessors, Netty should rely on a
method that enables configuration when the JVM is started or by the
application. This commit exposes a new class NettyRuntime for enabling
such configuraiton. This value can only be set once. Its default value
is Runtime#availableProcessors so that there is no visible change to
existing applications, but enables configuring either a system property
or configuring during application startup (e.g., based on settings used
to configure the application).
Additionally, we introduce the usage of forbidden-apis to prevent future
uses of Runtime#availableProcessors from creeping. Future work should
enable the bundled signatures and clean up uses of deprecated and
other forbidden methods.
Result:
Netty can be configured to not use the underlying number of processors,
but rather the constrained number of processors.
Motivation:
We need to release all the buffers that may be put into our inbound queue since we closed the Channel to ensure we not leak any memory. This is fine as it basically gives the same guarantees as TCP which means even if the promise was notified before its not really guaranteed that the "remote peer" will see the buffer at all.
Modifications:
Ensure we release all buffers in the inbound buffer if a doClose() is called.
Result:
No more leaks.
Motivation:
1. The use of InternetProtocolFamily is not consistent:
the DnsNameResolverContext and DnsNameResolver contains switches
instead of appropriate methods usage.
2. The InternetProtocolFamily class contains redundant switches in the
constructor.
Modifications:
1. Replacing switches to the use of an appropriate methods.
2. Simplifying the InternetProtocolFamily constructor.
Result:
Code is cleaner and simpler.
Motivation:
When a VoidChannelPromise is used by the user we need to ensure we propergate the exception through the ChannelPipeline otherwise the exception will just be swallowed and so the user has no idea whats going on.
Modifications:
- Always call tryFailure / trySuccess even when we use the VoidChannelPromise
- Add unit test
Result:
Fixes [#6622].
Motivation:
Commit 795f318 simplified some code related to the special case Set for the selected keys and introduced a Selector wrapper to make sure this set was properly reset. However the JDK makes assumptions about the type of Selector and this type is not extensible. This means whenever we call into the JDK we must provide the unwrapped version of the Selector or we get a ClassCastException. We missed a case of unwrapping in NioEventLoop#rebuildSelector0.
Modificaitons:
- NioEventLoop#openSelector should return a tuple so we can atomically set the wrapped and unwrapped Selector
- NioEventLoop#rebuildSelector0 should use the unwrapped version of the selector
Result:
Fixes https://github.com/netty/netty/issues/6607.
Motivation:
The code accidentally passes channel twice instead of value, resulting in logs like:
Failed to set channel option 'SO_SNDBUF' with value '[id: 0x2c5b2eb4]' for channel '[id: 0x2c5b2eb4]'
Modifications:
Pass value instead of channel where it needs to be.
Result:
Failed to set channel option 'SO_SNDBUF' with value '0' for channel '[id: 0x9bd3c5b8]'
Motivation:
We forked a new process to detect if the program is run by root. We should better just use user.name system property
Modifications:
- Change PlatformDependent.isRoot0() to read the user.name system property to detect if root runs the program and rename it to maybeSuperUser0().
- Rename PlatformDependent.isRoot() to maybeSuperUser() and let it init directly in the static block
Result:
Less heavy way to detect if the program is run by root.
Make the FileRegion comments about which transports are supported more accurate.
Also, eleminate any outstanding references to FileRegion.transfered as the method was renamed for spelling.
Modifications:
Class-level comment on FileRegion, can call renamed method.
Result:
More accurate documentation and less calls to deprecated methods.
Motivation:
There are numerous usages of internalNioBuffer which hard code 0 for the index when the intention was to use the readerIndex().
Modifications:
- Remove hard coded 0 for the index and use readerIndex()
Result:
We are less susceptible to using the wrong index, and don't make assumptions about the ByteBufAllocator.
Motivation:
Calling a static method is faster then dynamic
Modifications:
Add 'static' keyword for methods where it missed
Result:
A bit faster method calls
Motivation:
When "Too many open files" happens,the URLClassLoader cannot do any classloading because URLClassLoader need a FD for findClass. Because of this the anonymous inner class that is created to re-enable auto read may cause a problem.
Modification:
Pre-create Runnable that is scheduled and so ensure it is not lazy loaded.
Result:
No more problems when try to recover.
Motivation:
We have our own ThreadLocalRandom implementation to support older JDKs . That said we should prefer the JDK provided when running on JDK >= 7
Modification:
Using ThreadLocalRandom implementation of the JDK when possible.
Result:
Make use of JDK implementations when possible.
Motivation:
SelectedSelectionKeySet currently uses 2 arrays internally and users are expected to call flip() to access the underlying array and switch the active array. However we do not concurrently use 2 arrays at the same time and we can get away with using a single array if we are careful about when we reset the elements of the array.
Modifications:
- Introduce SelectedSelectionKeySetSelector which wraps a Selector and ensures we reset the underlying SelectedSelectionKeySet data structures before we select
- The loop bounds in NioEventLoop#processSelectedKeysOptimized can be defined more precisely because we know the real size of the underlying array
Result:
Fixes https://github.com/netty/netty/issues/6058
Motiviation:
Simplify implementation of compareTo/equals/hashCode for ChannelIds.
Modifications:
We simplfy the hashCode implementation for DefaultChannelId by not
making it random, but making it based on the underlying data. We fix the
compareTo implementation for DefaultChannelId by using lexicographic
comparison of the underlying data array. We fix the compareTo
implementation for CustomChannelId to avoid the possibility of overflow.
Result:
Cleaner code that is easier to maintain.
Motivation:
Initialization of PlatformDependent0 fails on Java 9 in static initializer when calling setAccessible(true).
Modifications:
Add RefelectionUtil which can be used to safely try if setAccessible(true) can be used or not and if not fail back to non reflection.
Result:
Fixed [#6345]
Motivation:
EPOLL annotates some exceptions to provide the remote address, but the original exception is not preserved. This may make determining a root cause more difficult. The static EPOLL exceptions references the native method that failed, but does not provide a description of the actual error number. Without the description users have to know intimate details about the native calls and how they may fail to debug issues.
Modifications:
- annotated exceptions should preserve the original exception
- static exceptions should include the string description of the expected errno
Result:
EPOLL exceptions provide more context and are more useful to end users.
Motivation:
EpollRecvByteAllocatorHandle intends to override the meaning of "maybe more data to read" which is a concept also used in all existing implementations of RecvByteBufAllocator$Handle but the interface doesn't support overriding. Because the interfaces lack the ability to propagate this computation EpollRecvByteAllocatorHandle attempts to implement a heuristic on top of the delegate which may lead to reading when we shouldn't or not reading data.
Modifications:
- Create a new interface ExtendedRecvByteBufAllocator and ExtendedHandle which allows the "maybe more data to read" between interfaces
- Deprecate RecvByteBufAllocator and change all existing implementations to extend ExtendedRecvByteBufAllocator
- transport-native-epoll should require ExtendedRecvByteBufAllocator so the "maybe more data to read" can be propagated to the ExtendedHandle
Result:
Fixes https://github.com/netty/netty/issues/6303.
Motivation:
Result of validatePromise() is always inverted with if (!validatePromise()).
Modification:
validatePromise() renamed to isNotValidPromise() and now returns inverted state so you don't need to invert state in conditions. Also name is now more meaningful according to returned result.
Added more tests for validatePromise corner cases with Exceptions.
Result:
Code easier to read. No need in inverted result.
Motivation:
We used various mocking frameworks. We should only use one...
Modifications:
Make usage of mocking framework consistent by only using Mockito.
Result:
Less dependencies and more consistent mocking usage.
Motivation:
NioDatagramChannel fails a write with NotYetConnectedException when the DatagramChannel was not yet connected and a ByteBuf is written. The same should be done for OioDatagramChannel as well.
Modifications:
Make OioDatagramChannel consistent with NioDatagramChannel
Result:
Correct and consistent implementations of DatagramChannel
Motivation:
Currently Netty does not wrap socket connect, bind, or accept
operations in doPrivileged blocks. Nor does it wrap cases where a dns
lookup might happen.
This prevents an application utilizing the SecurityManager from
isolating SocketPermissions to Netty.
Modifications:
I have introduced a class (SocketUtils) that wraps operations
requiring SocketPermissions in doPrivileged blocks.
Result:
A user of Netty can grant SocketPermissions explicitly to the Netty
jar, without granting it to the rest of their application.
