Use popen3 instead of `` for pack200 operations to drain STDIO.

If the pack200 operation is writing to STDOUT or STDERR and the buffer fills, the process will block. Since Kernel#`` is itself a blocking operation and won't drain STDIO until the command finishes, the whole process blocks forever.
jruby · Sep 24, 2015 · b40bc95 · b40bc95 · nirvdrum · Sep 24, 2015
1 parent a30da98
commit b40bc95
Showing 1 changed file with 17 additions and 1 deletion.
diff --git a/maven/jruby-dist/pom.rb b/maven/jruby-dist/pom.rb
@@ -47,6 +47,8 @@
     end
 
     execute :pack200 do |ctx|
+      require 'open3'
+
       jruby_home = Dir[ File.join( ctx.project.build.directory.to_pathname,
                                    'META-INF/jruby.home/**/*.jar' ) ]
       gem_home = Dir[ File.join( ctx.project.build.directory.to_pathname,
@@ -58,7 +60,21 @@
         file = f.sub /.jar$/, '' 
         unless File.exists?( file + '.pack.gz' )
           puts "pack200 #{f.sub(/.*jruby.home./, '').sub(/.*rubygems-provided./, '')}"
-          `pack200 #{file}.pack.gz #{file}.jar`
+
+          Open3.popen3('pack200', "#{file}.pack.gz", "#{file}.jar") do |stdin, stdout, stderr, wait_thread|
+            stdio_threads = []
+
+            stdio_threads <<  Thread.new(stdout) do |stdout|
+              stdout.each { |line| $stdout.puts line }
+            end
+
+            stdio_threads <<  Thread.new(stderr) do |stderr|
+              stderr.each { |line| $stderr.puts line }
+            end
+
+            stdio_threads.each(&:join)
+            wait_thread.value
+          end
         end
       end
     end