The locking is a downright crime (where's the STM when you need it),
and it's still racy, but it should work OK.
Excerpts from Edward Z. Yang's message of Mon Sep 03 00:59:31 -0400 2012:
> From: "Edward Z. Yang" <ezy...@mit.edu>
>
> Signed-off-by: Edward Z. Yang <ezy...@mit.edu>
> ---
> lib/sup/maildir.rb | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++--
> lib/sup/poll.rb | 33 ++++++++++++++++++++++++++-------
> lib/sup/source.rb | 4 ++++
> 3 files changed, 80 insertions(+), 9 deletions(-)
>
> diff --git a/lib/sup/maildir.rb b/lib/sup/maildir.rb
> index 2a91f05..743156d 100644
> --- a/lib/sup/maildir.rb
> +++ b/lib/sup/maildir.rb
> @@ -1,5 +1,6 @@
> require 'uri'
> require 'set'
> +require 'inotify'
>
> module Redwood
>
> @@ -184,6 +185,45 @@ class Maildir < Source
> nil
> end
>
> + def continuous_poll poll_mutex
> + i = Inotify.new
> + watches = {}
> + @ctimes.each do |d,prev_ctime|
> + subdir = File.join @dir, d
> + wd = i.add_watch(subdir, Inotify::CREATE | Inotify::DELETE |
> Inotify::MOVE)
> + watches[wd] = d
> + end
> + i.each_event do |ev|
> + poll_mutex.synchronize do
> + @mutex.synchronize do
> + begin
> + ::Thread.current[@dir] = true
> + id = File.join watches[ev.wd], ev.name
> + # check if inotify is stale
> + # since we have @mutex, there is no race (except for
> + # an external program fucking us over)
> + next unless File.exists? File.join(@dir, id)
> + x = Enumerator.new(Index.instance, :each_source_info, self.id,
> "#{id}").to_a
> + if ev.mask & Inotify::CREATE or ev.mask & Inotify::MOVE_TO
> + next unless x.empty?
> + yield :add,
> + :info => id,
> + :labels => @labels + maildir_labels(id) + [:inbox],
> + :progress => 0
> + elsif ev.mask & Inotify::DELETE or ev.mask & Inotify::MOVE_FROM
> + next unless !x.empty?
> + yield :delete,
> + :info => id,
> + :progress => 0
> + end
> + ensure
> + ::Thread.current[@dir] = nil
> + end
> + end
> + end
> + end
> + end
> +
> def labels? id
> maildir_labels id
> end
> @@ -248,7 +288,16 @@ private
> end
>
> def maildir_move_file orig_path, new_source_id, flags
> - @mutex.synchronize do
> + if ::Thread.current[@dir]
> + _maildir_move_file orig_path, new_source_id, flags
> + else
> + @mutex.synchronize do
> + _maildir_move_file orig_path, new_source_id, flags
> + end
> + end
> + end
> +
> + def _maildir_move_file orig_path, new_source_id, flags
> new_base = (flags.include?("S")) ? "cur" : "new"
> md_base, md_ver, md_flags = maildir_data orig_path
>
> @@ -292,7 +341,6 @@ private
> end
>
> [new_source, new_loc]
> - end
> end
> end
>
> diff --git a/lib/sup/poll.rb b/lib/sup/poll.rb
> index dbd351f..51e0afa 100644
> --- a/lib/sup/poll.rb
> +++ b/lib/sup/poll.rb
> @@ -94,11 +94,27 @@ EOS
> poll if @last_poll.nil? || (Time.now - @last_poll) >= @delay
> end
> end
> + # XXX dup dup
> + SourceManager.usual_sources.each do |source|
> + Redwood::reporting_thread("inotify poll for #{source}") do
> + source.continuous_poll @mutex do |sym, args|
> + poll_handler source, sym, args
> + end
> + end
> + end
> + SourceManager.unusual_sources.each do |source|
> + Redwood::reporting_thread("inotify poll for #{source}") do
> + source.continuous_poll @mutex do |sym, args|
> + poll_handler source, sym, args
> + end
> + end
> + end
> end
>
> def stop
> @thread.kill if @thread
> @thread = nil
> + # handle inotify polls
> end
>
> def do_poll
> @@ -172,7 +188,16 @@ EOS
> ## from the index after being yielded.
> def poll_from source, opts={}
> begin
> - source.poll do |sym, args|
> + source.poll do |sym,args|
> + poll_handler source, sym, args
> + end
> + source.go_idle
> + rescue SourceError => e
> + warn "problem getting messages from #{source}: #{e.message}"
> + end
> + end
> +
> + def poll_handler source, sym, args
> case sym
> when :add
> m = Message.build_from_source source, args[:info]
> @@ -224,12 +249,6 @@ EOS
> UpdateManager.relay self, :updated, m
> end
> end
> - end
> -
> - source.go_idle
> - rescue SourceError => e
> - warn "problem getting messages from #{source}: #{e.message}"
> - end
> end
>
> def handle_idle_update sender, idle_since; @should_clear_running_totals =
> false; end
> diff --git a/lib/sup/source.rb b/lib/sup/source.rb
> index 06b6e6b..073a10a 100644
> --- a/lib/sup/source.rb
> +++ b/lib/sup/source.rb
> @@ -102,6 +102,10 @@ class Source
> unimplemented
> end
>
> + ## Like poll, but never returns (it is continuous, and uses something
> + ## like inotify. Will always be run in another thread.)
> + def continuous_poll poll_mutex; [] end
> +
> def valid? info
> true
> end
_______________________________________________
Sup-devel mailing list
Sup-devel@rubyforge.org
http://rubyforge.org/mailman/listinfo/sup-devel
