pirocks/simple-named-pipes-ipc

A Java/Kotlin IPC library using named pipes

simple-named-pipes-ipc's Issues

Negation for contentType needs another approach

Thanks for writing this, I used it and found a bug.

When passing through an IntArray, on reading, it couldn't figure out the type from

contentsType.and(0x7f)

I couldn't think of a better shorthand so I just changed it to

val absolute = if(contentsType < 0) (-contentsType).toByte() else contentsType

Then used that. I'm sure you can think of something better. It seems to matter if it's a Byte or an Integer.

Finalize gets called when it shouldn't

This was a tricky one.

In the method openPipes(), it creates NamedPipes. If it throws because they already exist, it replaces the created ones with a different set of NamedPipe.

The problem is, the original NamedPipe had been created with a reference to an existing file. When the reference is broken, that instance is sometimes garbage collected. This calls finalize() on NamedPipe, which then calls close(), which then deletes the file. But that file, by definition, is currently being used by some other client.

The visible symptom was that the NamedPipe doing the reading (not the one that just got deleted) hangs when it's lazy loading its DataInputSteam. That's because the file it's referencing is gone, and is never written to.

It only happened sometimes. Weirdly, when I wrote my own tests, they would hang if I ran one of the tests by itself, but worked fine when I ran more than one test. Dunno why.

The solution is instead of using try catch in openPipes(), check for the two files' existence before deciding what to create.