Low-level Java error printed on Errno::EPIPE exception

[janko-m]

Environment

$ jruby -v
jruby 9.1.15.0 (2.3.3) 2017-12-07 929fde8 Java HotSpot(TM) 64-Bit Server VM 25.40-b25 on 1.8.0_40-b27 +jit [darwin-x86_64]
$ uname -a
Darwin Jankos-MacBook-Pro-2.local 17.3.0 Darwin Kernel Version 17.3.0: Thu Nov  9 18:09:22 PST 2017; root:xnu-4570.31.3~1/RELEASE_X86_64 x86_64

Expected Behavior

When writing to a broken pipe using IO.copy_stream, I expect Errno::EPIPE exception to be raised without anything else printed, as it is the case on MRI:

require "stringio"

read_pipe, write_pipe = IO.pipe
read_pipe.close

IO.copy_stream(StringIO.new("foo"), write_pipe)

script.rb:6:in `write': Broken pipe (Errno::EPIPE)
        from script.rb:6:in `copy_stream'
        from script.rb:6:in `<main>'

Actual Behavior

On JRuby, in addition to the Errno::EPIPE exception, we get a java.io.IOException: Broken pipe internal exception also printed out:

java.io.IOException: Broken pipe
        at sun.nio.ch.FileDispatcherImpl.write0(Native Method)
        at sun.nio.ch.FileDispatcherImpl.write(FileDispatcherImpl.java:60)
        at sun.nio.ch.IOUtil.writeFromNativeBuffer(IOUtil.java:93)
        at sun.nio.ch.IOUtil.write(IOUtil.java:65)
        at sun.nio.ch.SinkChannelImpl.write(SinkChannelImpl.java:167)
        at org.jruby.RubyIO.transfer(RubyIO.java:4323)
        at org.jruby.RubyIO.copy_stream(RubyIO.java:4205)
        at org.jruby.RubyIO$INVOKER$s$0$2$copy_stream.call(RubyIO$INVOKER$s$0$2$copy_stream.gen)
        at org.jruby.internal.runtime.methods.JavaMethod$JavaMethodN.call(JavaMethod.java:725)
        at org.jruby.internal.runtime.methods.DynamicMethod.call(DynamicMethod.java:208)
        at org.jruby.runtime.callsite.CachingCallSite.cacheAndCall(CachingCallSite.java:338)
        at org.jruby.runtime.callsite.CachingCallSite.call(CachingCallSite.java:183)
        at script.invokeOther6:copy_stream(script.rb:6)
        at script.RUBY$script(script.rb:6)
        at java.lang.invoke.MethodHandle.invokeWithArguments(MethodHandle.java:625)
        at org.jruby.ir.Compiler$1.load(Compiler.java:95)
        at org.jruby.Ruby.runScript(Ruby.java:831)
        at org.jruby.Ruby.runNormally(Ruby.java:750)
        at org.jruby.Ruby.runNormally(Ruby.java:768)
        at org.jruby.Ruby.runFromMain(Ruby.java:581)
        at org.jruby.Main.doRunFromMain(Main.java:417)
        at org.jruby.Main.internalRun(Main.java:305)
        at org.jruby.Main.run(Main.java:232)
        at org.jruby.Main.main(Main.java:204)
Errno::EPIPE: Broken pipe - Broken pipe
  copy_stream at org/jruby/RubyIO.java:4224
       <main> at script.rb:6

Note that the behaviour is still the same, an Errno::EPIPE exception is still raised, but in addition to that java.io.IOException: Broken pipe stack trace is displayed, even when I rescue Errno::EPIPE. The thing is that in my case I'm expecting that Errno::EPIPE will be raised in certain scenarios, so this internal Java stack trace is something that I would prefer wasn't there, because no exception was actually raised.

[enebo]

HAHAH that should have read 2014. Which was still impressively old but not EPIC

[janko-m]

@enebo Thank you for such a quick fix!

[janko-m]

@enebo I'm still seeing the same low-level Java error in JRuby 9.1.17.0 when I execute the script above.

[enebo]

@janko-m I do not see this:

jruby ../snippets/err3.rb 
Errno::EPIPE: Broken pipe - Broken pipe
        write at org/jruby/RubyIO.java:1431
  copy_stream at org/jruby/RubyIO.java:4697
       (root) at ../snippets/err3.rb:6

Is it possible there is an env like JRUBY_HOME or somehow the older jar is there? Also paste the new stacktrace/ The line numbers will definitely not be exactly the same; so if you see that then it is likely calling an older version still.

[janko-m]

Hmm, that's strange. Here is the stack trace:

shrine[master, jruby-9.1.17.0]$ ruby script.rb 
java.io.IOException: Broken pipe
        at sun.nio.ch.FileDispatcherImpl.write0(Native Method)
        at sun.nio.ch.FileDispatcherImpl.write(FileDispatcherImpl.java:60)
        at sun.nio.ch.IOUtil.writeFromNativeBuffer(IOUtil.java:93)
        at sun.nio.ch.IOUtil.write(IOUtil.java:65)
        at sun.nio.ch.SinkChannelImpl.write(SinkChannelImpl.java:167)
        at org.jruby.RubyIO.transfer(RubyIO.java:4406)
        at org.jruby.RubyIO.copy_stream(RubyIO.java:4295)
        at org.jruby.RubyIO$INVOKER$s$0$2$copy_stream.call(RubyIO$INVOKER$s$0$2$copy_stream.gen)
        at org.jruby.internal.runtime.methods.JavaMethod$JavaMethodN.call(JavaMethod.java:800)
        at org.jruby.internal.runtime.methods.DynamicMethod.call(DynamicMethod.java:210)
        at org.jruby.runtime.callsite.CachingCallSite.cacheAndCall(CachingCallSite.java:338)
        at org.jruby.runtime.callsite.CachingCallSite.call(CachingCallSite.java:183)
        at script.invokeOther6:copy_stream(script.rb:6)
        at script.RUBY$script(script.rb:6)
        at java.lang.invoke.MethodHandle.invokeWithArguments(MethodHandle.java:625)
        at org.jruby.ir.Compiler$1.load(Compiler.java:94)
        at org.jruby.Ruby.runScript(Ruby.java:830)
        at org.jruby.Ruby.runNormally(Ruby.java:749)
        at org.jruby.Ruby.runNormally(Ruby.java:767)
        at org.jruby.Ruby.runFromMain(Ruby.java:580)
        at org.jruby.Main.doRunFromMain(Main.java:417)
        at org.jruby.Main.internalRun(Main.java:305)
        at org.jruby.Main.run(Main.java:232)
        at org.jruby.Main.main(Main.java:204)
Errno::EPIPE: Broken pipe - Broken pipe
  copy_stream at org/jruby/RubyIO.java:4302
       <main> at script.rb:6

I deleted the previous JRuby version with rm -rf ~/.rbenv/versions/jruby-9.1.15.0, just in case. I don't have $JRUBY_HOME set, and I don't see any Ruby-related env vars that could cause this:

RBENV_SHELL=bash
RBENV_VERSION=jruby-9.1.17.0
RUBY_GC_HEAP_FREE_SLOTS=200000
RUBY_GC_MALLOC_LIMIT=60000000

I actually first noticed the output still being there in the Travis CI build output for shrinerb/shrine, after I had upgraded to jruby-9.1.17.0. I think it'd be strange if both my local and Travis CI were somehow caching an older JRuby version 🤔

[enebo]

@janko-m oh ffs :| yeah I committed this to our master branch and not out jruby-9.1 branch :( Sorry for a) not actually fixing it in the right place b) making you verify it is actually broken.

[janko-m]

No problem, thanks for pushing it out to the jruby-9.1 branch 😃