netty5/transport-native-epoll
Norman Maurer 03aafb9cff
Unregister all previous registered native methods if loading of native code fails… (#10719)
Motivation:

It's important to unload all previous registered native methods when there is a failure during loading the native lib. Failing to do so may lead to an "invalid state" and so may segfault the JVM when trying to call a native method that was previous loaded.

This was observed when two versions of netty-tcnative were on the classpath which had different requirements in terms of linking.

Something like this was reported in he hs log:

```
Instructions: (pc=0x0000000116413bf0)
0x0000000116413bd0:
[error occurred during error reporting (printing registers, top of stack, instructions near pc), id 0xb]

Register to memory mapping:

RAX=0x0000000116413bf0 is an unknown value
RBX={method} {0x000000011422e708} 'aprMajorVersion' '()I' in 'io/netty/internal/tcnative/Library'
RCX=0x000000000000000a is an unknown value
RDX=0x000000000000000a is an unknown value
```

Modifications:

- Unregister previous registered native methods on failure
- Unregister previous registered native methods on on unload of the native lib

Result:

No more segfault caused by invalid state when loading of the native lib fails in between. In this case the user will receive an error now like:
2020-10-26 14:15:04 +01:00
..
src Unregister all previous registered native methods if loading of native code fails… (#10719) 2020-10-26 14:15:04 +01:00
pom.xml Enable nohttp check during the build (#10708) 2020-10-23 14:44:18 +02:00
README.md Change the netty.io homepage scheme(http -> https) (#9344) 2019-07-09 21:09:42 +02:00

Native transport for Linux

See our wiki page.