RFR: 8252324: Signal related code should be shared among POSIX platforms

[Yasumasa Suenaga]

On Sat, 3 Oct 2020 17:12:30 GMT, Gerard Ziemski <gziemski at openjdk.org> wrote:

> This is a fresh start for https://github.com/openjdk/jdk/pull/157
> 
> Please review this change that refactors common POSIX code into a separate
> file.
> 
> Currently there appears to be quite a bit of duplicated code among POSIX
> platforms, which makes it difficult to apply single fix to the signal code.
> With this fix, we will only need to touch single file for common POSIX
> code fixes from now on.
> 
> ---------
> ### Progress
> - [x] Change must not contain extraneous whitespace
> - [x] Commit message must refer to an issue
> - [ ] Change must be properly reviewed
> 
> 
> 
> ### Download
> `$ git fetch https://git.openjdk.java.net/jdk pull/497/head:pull/497`
> `$ git checkout pull/497`

src/hotspot/os/posix/signals_posix.cpp line 688:

> 686:     tty->print("  found:");
> 687:     print_sa_flags(tty, act.sa_flags);
> 688:     tty->cr();

Can we use unified logging at here? If do so, we should out them with single line.

src/hotspot/os/posix/signals_posix.cpp line 271:

> 269: void PosixSignals::jdk_misc_signal_init() {
> 270:   // Initialize signal structures
> 271:   ::memset((void*)pending_signals, 0, sizeof(pending_signals));

Is this code needed? `pending_signals` is initialized with `{ 0 }` and also `jdk_misc_signal_init()` would be called
from `os::init_2()` .

-------------

PR: https://git.openjdk.java.net/jdk/pull/497