8358764: (sc) SocketChannel.close when thread blocked in read causes connection to be reset (win)

[GoeLin]

I backport this for parity with 17.0.18-oracle.

Needed resolve and adaptions:

Net.java: resolved static initializer.
SocketChannelImpl.java: In implCloseBlockingMode(), the code guarded by the new condition is not in 17. Omitted.
Net.c: Copyright.

The test exercises platform and virtual threads.
I simplified this to what is supported in 17.
See extra commit.

---

Progress

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• JDK-8358764 needs maintainer approval

Issue

• JDK-8358764: (sc) SocketChannel.close when thread blocked in read causes connection to be reset (win) (Bug - P3)

Reviewers

• Martin Doerr (@TheRealMDoerr - Reviewer)

Reviewing

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[bridgekeeper]

👋 Welcome back goetz! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

This backport pull request has now been updated with issue from the original commit.

[mlbridge]

Webrevs

• 01: Full - Incremental (bdb4707e)
• 00: Full (d57767e8)

[TheRealMDoerr]

It is true that the affected part of implCloseBlockingMode() has been introduced with Loom, but it looks relevant without Loom, too. Note that implCloseNonBlockingMode() handles StandardSocketOptions.SO_LINGER, too.

Without this change, your PR basically only adds a test because shouldShutdownWriteBeforeClose() is unused.

diff --git a/src/java.base/share/classes/sun/nio/ch/SocketChannelImpl.java b/src/java.base/share/classes/sun/nio/ch/SocketChannelImpl.java
index a771d998b24..09c9ed4df99 100644
--- a/src/java.base/share/classes/sun/nio/ch/SocketChannelImpl.java
+++ b/src/java.base/share/classes/sun/nio/ch/SocketChannelImpl.java
@@ -1019,7 +1019,19 @@ class SocketChannelImpl
     private void implCloseBlockingMode() throws IOException {
         synchronized (stateLock) {
             assert state < ST_CLOSING;
+            boolean connected = (state == ST_CONNECTED);
             state = ST_CLOSING;
+
+            if (connected && Net.shouldShutdownWriteBeforeClose()) {
+                // shutdown output when linger interval not set to 0
+                try {
+                    var SO_LINGER = StandardSocketOptions.SO_LINGER;
+                    if ((int) Net.getSocketOption(fd, SO_LINGER) != 0) {
+                        Net.shutdown(fd, Net.SHUT_WR);
+                    }
+                } catch (IOException ignore) { }
+            }
+
             if (!tryClose()) {
                 long reader = readerThread;
                 long writer = writerThread;

[TheRealMDoerr]

Thanks! This backport LGTM, now. It would be great if someone from the core-libs team could confirm that the SO_LINGER code is adequate for 17u.

[openjdk]

⚠️ @GoeLin This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.