+++ /dev/null
-;;;; -*- Mode: LISP; Syntax: ANSI-Common-Lisp; Base: 10 -*-
-;;;; *************************************************************************
-;;;;
-;;;; $Id$
-;;;;
-;;;; Transaction support
-;;;;
-;;;; This file is part of CLSQL.
-;;;;
-;;;; 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.
-;;;; *************************************************************************
-
-(in-package #:clsql-base)
-
-(defclass transaction ()
- ((commit-hooks :initform () :accessor commit-hooks)
- (rollback-hooks :initform () :accessor rollback-hooks)
- (status :initform nil :accessor transaction-status))) ; nil or :committed
-
-(defun commit-transaction (database)
- (when (and (transaction database)
- (not (transaction-status (transaction database))))
- (setf (transaction-status (transaction database)) :committed)))
-
-(defun add-transaction-commit-hook (database commit-hook)
- (when (transaction database)
- (push commit-hook (commit-hooks (transaction database)))))
-
-(defun add-transaction-rollback-hook (database rollback-hook)
- (when (transaction database)
- (push rollback-hook (rollback-hooks (transaction database)))))
-
-(defmethod database-start-transaction (database)
- (unless database (error 'clsql-no-database-error))
- (unless (transaction database)
- (setf (transaction database) (make-instance 'transaction)))
- (when (= (incf (transaction-level database) 1))
- (let ((transaction (transaction database)))
- (setf (commit-hooks transaction) nil
- (rollback-hooks transaction) nil
- (transaction-status transaction) nil)
- (execute-command "BEGIN" :database database))))
-
-(defmethod database-commit-transaction (database)
- (if (> (transaction-level database) 0)
- (when (zerop (decf (transaction-level database)))
- (execute-command "COMMIT" :database database)
- (map nil #'funcall (commit-hooks (transaction database))))
- (warn 'clsql-simple-warning
- :format-control "Cannot commit transaction against ~A because there is no transaction in progress."
- :format-arguments (list database))))
-
-(defmethod database-abort-transaction (database)
- (if (> (transaction-level database) 0)
- (when (zerop (decf (transaction-level database)))
- (unwind-protect
- (execute-command "ROLLBACK" :database database)
- (map nil #'funcall (rollback-hooks (transaction database)))))
- (warn 'clsql-simple-warning
- :format-control "Cannot abort transaction against ~A because there is no transaction in progress."
- :format-arguments (list database))))
-
-
-(defmacro with-transaction ((&key (database '*default-database*)) &rest body)
- "Executes BODY within a transaction for DATABASE (which defaults to
-*DEFAULT-DATABASE*). The transaction is committed if the body finishes
-successfully (without aborting or throwing), otherwise the database is
-rolled back."
- (let ((db (gensym "db-")))
- `(let ((,db ,database))
- (unwind-protect
- (progn
- (database-start-transaction ,db)
- ,@body
- (commit-transaction ,db))
- (if (eq (transaction-status (transaction ,db)) :committed)
- (database-commit-transaction ,db)
- (database-abort-transaction ,db))))))
-
-(defun commit (&key (database *default-database*))
- "Commits changes made to DATABASE which defaults to *DEFAULT-DATABASE*."
- (database-commit-transaction database))
-
-(defun rollback (&key (database *default-database*))
- "Rolls back changes made in DATABASE, which defaults to
-*DEFAULT-DATABASE* since the last commit, that is changes made since
-the last commit are not recorded."
- (database-abort-transaction database))
-
-(defun start-transaction (&key (database *default-database*))
- "Starts a transaction block on DATABASE which defaults to
-*default-database* and which continues until ROLLBACK or COMMIT are
-called."
- (unless (in-transaction-p :database database)
- (database-start-transaction database)))
-
-(defun in-transaction-p (&key (database *default-database*))
- "A predicate to test whether we are currently within the scope of a
-transaction in DATABASE."
- (and database (transaction database) (= (transaction-level database) 1)))