r2741: Start migration to pathname-less asd files, remove .system files

[clsql.git] / sql / pool.cl

diff --git a/sql/pool.cl b/sql/pool.cl
new file mode 100644 (file)
index 0000000..f4d965c
--- /dev/null
+++ b/sql/pool.cl
@@ -0,0 +1,79 @@
+;;;; -*- Mode: LISP; Syntax: ANSI-Common-Lisp; Base: 10 -*-
+;;;; *************************************************************************
+;;;; FILE IDENTIFICATION
+;;;;
+;;;; Name:          pool.cl
+;;;; Purpose:       Support function for connection pool
+;;;; Programmers:   Kevin M. Rosenberg, Marc Battyani
+;;;; Date Started:  Apr 2002
+;;;;
+;;;; $Id: pool.cl,v 1.8 2002/09/17 17:16:43 kevin Exp $
+;;;;
+;;;; This file, part of CLSQL, is Copyright (c) 2002 by Kevin M. Rosenberg
+;;;;
+;;;; CLSQL users are granted the rights to distribute and use this software
+;;;; as governed by the terms of the Lisp Lesser GNU Public License
+;;;; (http://opensource.franz.com/preamble.html), also known as the LLGPL.
+;;;; *************************************************************************
+
+(declaim (optimize (debug 3) (speed 3) (safety 1) (compilation-speed 0)))
+(in-package :clsql-sys)
+
+(defvar *db-pool* (make-hash-table :test #'equal))
+
+(defclass conn-pool ()
+  ((connection-spec :accessor connection-spec :initarg :connection-spec)
+   (database-type :accessor database-type :initarg :database-type)
+   (free-connections :accessor free-connections
+                    :initform (make-array 5 :fill-pointer 0 :adjustable t))
+   (all-connections :accessor all-connections
+                   :initform (make-array 5 :fill-pointer 0 :adjustable t))))
+
+(defun acquire-from-conn-pool (pool)
+  (if (zerop (length (free-connections pool)))
+    (let ((conn (connect (connection-spec pool)
+                        :database-type (database-type pool) :if-exists :new)))
+      (vector-push-extend conn (all-connections pool))
+      (setf (conn-pool conn) pool)
+      conn)
+    (vector-pop (free-connections pool))))
+
+(defun release-to-conn-pool (conn)
+  (vector-push-extend conn (free-connections (conn-pool conn))))
+
+(defun clear-conn-pool (pool)
+  (loop for conn across (all-connections pool)
+       do (setf (conn-pool conn) nil)
+          (disconnect :database conn))
+  (setf (fill-pointer (free-connections pool)) 0)
+  (setf (fill-pointer (all-connections pool)) 0))
+
+(defun find-or-create-connection-pool (connection-spec database-type)
+  "Find connection pool in hash table, creates a new connection pool if not found"
+  (let* ((key (list connection-spec database-type))
+        (conn-pool (gethash key *db-pool*)))
+    (unless conn-pool
+      (setq conn-pool (make-instance 'conn-pool
+                                    :connection-spec connection-spec
+                                    :database-type database-type))
+      (setf (gethash key *db-pool*) conn-pool))
+    conn-pool))
+
+(defun acquire-from-pool (connection-spec database-type &optional pool)
+  (unless (typep pool 'conn-pool)
+    (setf pool (find-or-create-connection-pool connection-spec database-type)))
+  (acquire-from-conn-pool pool))
+
+(defun release-to-pool (database)
+  (release-to-conn-pool database))
+
+(defun disconnect-pooled (&optional clear)
+  "Disconnects all connections in the pool"
+  (maphash
+   #'(lambda (key conn-pool)
+       (declare (ignore key))
+       (clear-conn-pool conn-pool))
+   *db-pool*)
+  (when clear (clrhash *db-pool*))
+  t)
+