lib/svn2git/migration.rb in svn2git-2.2.5 vs lib/svn2git/migration.rb in svn2git-2.3.0

@@ -1,7 +1,9 @@
 require 'optparse'
 require 'pp'
+require 'open4'
+require 'timeout'
 
 module Svn2Git
   DEFAULT_AUTHORS_FILE = "~/.svn2git/authors"
 
   class Migration
@@ -338,26 +340,82 @@
 
     def run_command(cmd, exit_on_error=true, printout_output=false)
       log "Running command: #{cmd}"
 
       ret = ''
+      @mutex ||= Mutex.new
+      @stdin_queue ||= Queue.new
 
-      cmd = "2>&1 #{cmd}"
-      IO.popen(cmd) do |stdout|
-        if printout_output
-          stdout.each_char do |character|
-            $stdout.print character
-            ret << character
-          end
-        else
+      # We need to fetch input from the user to pass through to the underlying sub-process.  We'll constantly listen
+      # for input and place any received values on a queue for consumption by a pass-through thread that will forward
+      # the contents to the underlying sub-process's stdin pipe.
+      @stdin_thread ||= Thread.new do
+        loop { @stdin_queue << $stdin.gets.chomp }
+      end
+
+      # Open4 forks, which JRuby doesn't support.  But JRuby added a popen4-compatible method on the IO class,
+      # so we can use that instead.
+      status = (defined?(JRUBY_VERSION) ? IO : Open4).popen4(cmd) do |pid, stdin, stdout, stderr|
+        threads = []
+
+        threads << Thread.new(stdout) do |stdout|
           stdout.each do |line|
-            log line
-            ret << line
+            @mutex.synchronize do
+              ret << line
+
+              if printout_output
+                $stdout.print line
+              else
+                log line
+              end
+            end
           end
         end
+
+        threads << Thread.new(stderr) do |stderr|
+          # git-svn seems to do all of its prompting for user input via STDERR.  When it prompts for input, it will
+          # not terminate the line with a newline character, so we can't split the input up by newline.  It will,
+          # however, use a space to separate the user input from the prompt.  So we split on word boundaries here
+          # while draining STDERR.
+          stderr.each(' ') do |word|
+            @mutex.synchronize do
+              ret << word
+
+              if printout_output
+                $stdout.print word
+              else
+                log word
+              end
+            end
+          end
+        end
+
+        # Simple pass-through thread to take anything the user types via STDIN and passes it through to the
+        # sub-process's stdin pipe.
+        Thread.new(stdin) do |stdin|
+          loop do
+            user_reply = @stdin_queue.pop
+
+            # nil is our cue to stop looping (pun intended).
+            break if user_reply.nil?
+
+            stdin.puts user_reply
+            stdin.close
+          end
+        end
+
+        threads.each(&:join)
+
+        # Push nil to the stdin_queue to gracefully exit the STDIN pass-through thread.
+        @stdin_queue << nil
       end
 
-      if exit_on_error && ($?.exitstatus != 0)
+      # JRuby's open4 doesn't return a Process::Status object when invoked with a block, but rather returns the
+      # block expression's value.  The Process::Status is stored as $?, so we need to normalize the status
+      # object if on JRuby.
+      status = $? if defined?(JRUBY_VERSION)
+
+      if exit_on_error && (status.exitstatus != 0)
         $stderr.puts "command failed:\n#{cmd}"
         exit -1
       end
 
       ret