X-Git-Url: https://git.distorted.org.uk/~mdw/lisp/blobdiff_plain/d7d819976cb5d84766bffd2c5272c86203687ee9..562ed2ddc451abe9be0ec5bb9684b2df56942d8f:/safely.lisp diff --git a/safely.lisp b/safely.lisp index b5d7ff8..9809f07 100644 --- a/safely.lisp +++ b/safely.lisp @@ -33,7 +33,13 @@ #+(or cmu sbcl) (eval-when (:compile-toplevel :execute) (import #+cmu '(ext:unix-namestring unix:unix-link) - #+sbcl '(sb-int:unix-namestring))) + #+sbcl '(sb-ext:native-namestring))) +#+cmu +(progn + (declaim (inline unix-namestring)) + (defun native-namestring (pathname &key as-file) + (declare (ignore as-file)) + (unix-namestring pathname nil))) (defstruct (safely (:predicate safelyp)) "Stores information about how to commit or undo safe writes." @@ -104,6 +110,13 @@ (safely-trail safe)) stream)) +(declaim (inline rename)) +(defun rename (old new) + (let ((target (make-pathname :directory '(:relative) + :defaults new))) + #-clisp (rename-file old target) + #+clisp (rename-file old target :if-exists :overwrite))) + (defun delete-file-without-moaning (file) "Delete the FILE, ignoring errors." (handler-case (delete-file file) @@ -112,7 +125,7 @@ (defun rename-file-without-moaning (old new) "Rename OLD to NEW, ignoring errors, and without doing any stupid name mangling." - (handler-case (rename-file old new) + (handler-case (rename old new) (file-error () nil))) (defun safely-unwind (trail) @@ -153,11 +166,23 @@ ;; Use link(2) where available. (generate-fresh-file-name file tag (lambda (name) - (let ((from (unix-namestring file t)) - (to (unix-namestring name nil))) + (let ((from (native-namestring file + :as-file t)) + (to (native-namestring name + :as-file t))) (and from to (unix-link from to))))) + #+clisp + (generate-fresh-file-name file tag + (lambda (name) + (posix:copy-file (namestring file) + (namestring name) + :method :hardlink + :if-exists nil))) + + + #-(or cmu sbcl) ;; Otherwise just copy the file contents and hope for the best. (with-open-file (input file :element-type :default) @@ -197,23 +222,23 @@ (loop (unless trail (return)) - (let ((job (pop trail))) - (ecase (car job) - (:shunt (destructuring-bind (tag new file) job - (declare (ignore tag)) - (push `(:rmtmp ,new) revert) - (if (probe-file file) - (let ((old (safe-copy file "old"))) - (push `(:rmtmp ,old) cleanup) - (push `(:revert ,old ,file) revert)) - (push `(:rmtmp ,file) revert)) - (rename-file new file))) - (:delete (destructuring-bind (tag file) job - (declare (ignore tag)) - (let ((old (safe-copy file "delete"))) - (push `(:revert ,old ,file) revert) - (push `(:rmtmp ,old) cleanup) - (delete-file file))))))) + (let ((job (pop trail))) + (ecase (car job) + (:shunt (destructuring-bind (tag new file) job + (declare (ignore tag)) + (push `(:rmtmp ,new) revert) + (if (probe-file file) + (let ((old (safe-copy file "old"))) + (push `(:rmtmp ,old) cleanup) + (push `(:revert ,old ,file) revert)) + (push `(:rmtmp ,file) revert)) + (rename new file))) + (:delete (destructuring-bind (tag file) job + (declare (ignore tag)) + (let ((old (safe-copy file "delete"))) + (push `(:revert ,old ,file) revert) + (push `(:rmtmp ,old) cleanup) + (delete-file file))))))) (setf revert nil)) (safely-unwind trail) (safely-unwind revert) @@ -237,8 +262,7 @@ temporary file, and if BODY completes, it is renamed to FILE." (with-gensyms safe `(safely (,safe) - (let ((,stream (apply #'safely-open-output-stream - ,safe ,file ,open-args))) + (let ((,stream (safely-open-output-stream ,safe ,file ,@open-args))) ,@body)))) ;;;----- That's all, folks --------------------------------------------------