exec_cgi: release pipe/pid sooner

We don't want to leave extra resources lying around when slow
clients read from us and yahns is forced to buffer.

yahns delays the close of the request body until the request is
fully written so response loggers can have an accurate time of
how long it takes.

1 files changed, 14 insertions, 7 deletions

diff --git a/extras/exec_cgi.rb b/extras/exec_cgi.rb
index 170e773..c18c758 100644
--- a/extras/exec_cgi.rb
+++ b/extras/exec_cgi.rb
@@ -19,17 +19,24 @@ class ExecCgi
       end
       yield("0\r\n\r\n") if @chunked
       self
+    ensure
+      # do this sooner, since the response body may be buffered, we want
+      # to release our FD as soon as possible.
+      close
     end
 
     def close
+      # yahns will call this again after its done writing the response
+      # body, so we must ensure its idempotent.
+      # Note: this object (and any client-specific objects) will never
+      # be shared across different threads, so we do not need extra
+      # mutual exclusion here.
+      return if closed?
       super
-      if defined?(@my_pid) && @my_pid
-        begin
-          Process.waitpid(@my_pid)
-        rescue Errno::ECHILD
-        end
-      end
-      nil
+      begin
+        Process.waitpid(@my_pid)
+      rescue Errno::ECHILD
+      end if defined?(@my_pid) && @my_pid
     end
   end