Restoring the state of a set of files

A computer program library residing on a computer-readable medium for adding the semantics of transactions to a set of native operations of a native file system by adding committal and roll back functionality to such native file system, the library comprising:

• (a) a set of one or more families of routines, each family of routines including a perform routine, a finalize routine, and an undo routine, each family of routines corresponding to at least one native operation and adapted to be invoked in lieu of the corresponding native operations;
• and
• (b) a transaction master including an opening routine for opening a transaction of native file system operations, a committing routine for committing such a transaction, and a roll back routine for rolling back such a transaction;
• where
• (c) the perform routine of each family includes computer instructions for causing a computer to give the appearance of performing one of the family's corresponding native operations and providing a functional equivalent thereof;
• (d) the finalize routine of each family includes computer instructions for causing a computer to commit one of the functional equivalents of one of the family's corresponding native operations;
• (e) the undo routine of each family includes computer instructions for causing a computer to roll back one of the functional equivalents of one of the family's corresponding native operations;
• (f) the committing routine includes computer instructions for causing a computer to read a transaction log;
• (g) the roll back routine includes computer instructions for causing a computer to read the transaction log;
• (h) the perform routines of the set of families of routines collectively include computer instructions for causing a computer to append transaction information to the transaction log such as identifying finalize and undo routines;
• (i) the committing routine includes computer instructions for causing a computer to invoke finalize routines identified in the transaction log;
• (j) the roll back routine includes computer instructions for causing a computer to invoke undo routines identified in the transaction log.

A method for providing transactional file operations for restoring the state of a set of files in a native computer file system having native modification operations for modifying the state of the files or the file system, the method comprising the steps of:

• (a) providing for each of a set of the modification operations a perform routine, a finalize routine, and an undo routine, such that each of these routines then has a corresponding modification operation executable on a computer system, where the perform and finalize routines collectively include computer instructions for causing a computer to effect the corresponding modification operation, and where the finalize and undo routines collectively include computer instructions for causing a computer to effect the roll back of the corresponding modification operation;
• (b) providing a transaction master including a transaction open routine for opening a transaction that includes modification operations, a commit routine for committing such a transaction, and a roll back routine for rolling back such a transaction, where the commit routine includes computer instructions for causing a computer to invoke finalize routines, and where the roll back routine includes computer instructions for causing a computer to invoke undo routines;
• where
• (c) the commit routine on invocation commits all open transactions;
• and
• (d) the roll back routine on invocation rolls back all open transactions.