Rewrite comment code for better modularity, and add necessary locking.

Robert Haas <rhaas@postgresql.org>

Commit: c10575ff005c330d0475345621b7d381eb510c48
Author: Robert Haas <rhaas@postgresql.org>
Date: 2010-08-27T11:47:41Z
Releases: 9.1.0
Rewrite comment code for better modularity, and add necessary locking.

Review by Alvaro Herrera, KaiGai Kohei, and Tom Lane.

Files