From: Nathan Bird <nathan@acceleration.net>
Date: Mon, 1 Mar 2010 19:08:41 +0000 (-0500)
Subject: Adding some TODO notes about potential race conditions.
X-Git-Tag: v5.0.5~8^2^2~12
X-Git-Url: http://git.kpe.io/?p=clsql.git;a=commitdiff_plain;h=4167624fd56f67ca02b6bf5f4b791bf5c4ccf7ef

Adding some TODO notes about potential race conditions.
---

diff --git a/TODO b/TODO
index 4b85e96..795ec6a 100644
--- a/TODO
+++ b/TODO
@@ -22,3 +22,6 @@ POSSIBLE EXTENSIONS
 
 * improve large object api and extend to databases beyond postgresql 
 * add support for prepared statements
+
+RACE CONDITIONS
+* sql/databases.lisp: *connected-databases* is shared globally but not modified in a threadsafe manner.
diff --git a/sql/database.lisp b/sql/database.lisp
index 382f552..bb87046 100644
--- a/sql/database.lisp
+++ b/sql/database.lisp
@@ -18,6 +18,8 @@
 CONNECT. Meaningful values are :new, :warn-new, :error, :warn-old
 and :old.")
 
+;;TODO: this variable appears to be global, not thread specific and is
+;; not protected when modifying the list.
 (defvar *connected-databases* nil
   "List of active database objects.")
 
@@ -174,6 +176,7 @@ from a pool it will be released to this pool."
                 (setf *default-database* (car *connected-databases*)))
               t))
           (when (database-disconnect database)
+	    ;;TODO: RACE COND: 2 threads disconnecting could stomp on *connected-databases*
             (setf *connected-databases* (delete database *connected-databases*))
             (when (eq database *default-database*)
               (setf *default-database* (car *connected-databases*)))