X-Git-Url: https://git.distorted.org.uk/~mdw/lisp/blobdiff_plain/b2c12b4eaf6e5c43791d95080a243c35f97ee488..6a1150352d374e8e76143bf47943069af093a8c9:/safely.lisp?ds=sidebyside diff --git a/safely.lisp b/safely.lisp index 0a05f8b..9e723ed 100644 --- a/safely.lisp +++ b/safely.lisp @@ -30,6 +30,11 @@ #:safely-writing)) (in-package #:safely) +#+(or cmu sbcl) +(eval-when (:compile-toplevel :execute) + (import #+cmu '(ext:unix-namestring unix:unix-link) + #+sbcl '(sb-int:unix-namestring))) + (defstruct (safely (:predicate safelyp)) "Stores information about how to commit or undo safe writes." (streams nil) @@ -99,6 +104,11 @@ (safely-trail safe)) stream)) +(declaim (inline rename)) +(defun rename (old new) + #-clisp (rename-file old new) + #+clisp (posix:copy-file old new :method :rename)) + (defun delete-file-without-moaning (file) "Delete the FILE, ignoring errors." (handler-case (delete-file file) @@ -107,7 +117,7 @@ (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) @@ -136,19 +146,34 @@ (safely-unwind (safely-trail safe)) (safely-reset safe)) +#+sbcl +(defun unix-link (from to) + (sb-unix::int-syscall ("link" sb-alien:c-string sb-alien:c-string) + from to)) + (defun safe-copy (file tag) "Make a copy of the FILE. Return the new name." - #+cmu + #+(or cmu sbcl) ;; Use link(2) where available. (generate-fresh-file-name file tag (lambda (name) - (let ((from (ext:unix-namestring file t)) - (to (ext:unix-namestring name nil))) + (let ((from (unix-namestring file t)) + (to (unix-namestring name nil))) (and from to - (unix:unix-link 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))) + + - #-cmu + #-(or cmu sbcl) ;; Otherwise just copy the file contents and hope for the best. (with-open-file (input file :element-type :default) (multiple-value-bind @@ -197,7 +222,7 @@ (push `(:rmtmp ,old) cleanup) (push `(:revert ,old ,file) revert)) (push `(:rmtmp ,file) revert)) - (rename-file new file))) + (rename new file))) (:delete (destructuring-bind (tag file) job (declare (ignore tag)) (let ((old (safe-copy file "delete"))) @@ -227,8 +252,7 @@ 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 --------------------------------------------------