"Renaming: permission denied" file-error in Windows

"Renaming: permission denied" file-error in Windows

[LynX]

Hello,

I found that dired in Windows does not provide you possibility to move a 
directory to a new location if this new location resides on a different 
logical disk.

For instance you have two opened dired buffers: `c:\dir1' and 
`f:\dir2'. To move some files from `dir1' to `dir2' you can use "R", but 
if you try to move some directory from `dir1' to `dir2' you will get 
`Renaming: permission denied' error message.

The problem occurs when dired calls Emacs function which delegates the 
call to native POSIX function `rename'.

In Windows `rename' operates a bit different than in other systems. 
According to MSDN [http://msdn.microsoft.com/en-us/library/zw5t957f.aspx]:

-- "You can use rename to move a file from one directory or device to 
another by giving a different path in the newname argument. However, you 
cannot use rename to move a directory." --

Whereas, in standard POSIX spec such constraint was not found.

Following code workarounds this problem by wrapping dired function
`dired-rename-file'. So when `Renaming: permission denied' error occurs, 
it tries to move the directory again by moving each of it files 
recursively to a new destination, recreating the source directory with 
its subdirectory structure.

If it also fails to do this due to real permission problems then it 
sends original error message.

Regards,
LX


(defadvice dired-rename-file
   (around my-dired-rename-file
     (file newname ok-if-already-exists))
   "This advice definition helps to deal with
`Renaming: permission denied' error message when moving
directories between different logical disks in dired.
This is a Windows specific problem."
   (condition-case err
     ad-do-it
     (file-error
       (and
         (string-starts-with
           (error-message-string err)
           "Renaming: permission denied")
         (file-directory-p file)
         (move-directory-recursively file newname)))))
(ad-activate 'dired-rename-file t)


(defun move-directory-recursively (dir-src dir-dst)
   "Moves directory DIR-SRC to the DIR-DST recursively.
To move directory dir1 into the directory dir2 you should
call this function like as follows:
   (move-directory-recursively `dir1' `dir2/dir1')
To move content of the directory dir1 into the directory
dir2:
   (move-directory-recursively `dir1' `dir2')
If dir2 does not exist it will be created."
   (let ((queue (list (cons dir-src dir-dst)))
         dir-dst dir-src remove-later)
     (while queue
       (let ((dir-src-dst (car queue)))
         (setq dir-src (car dir-src-dst))
         (setq dir-dst (cdr dir-src-dst)))
       (setq queue (cdr queue))
       ;; if dir-dst is a file signal an error
       (and
         (file-exists-p dir-dst)
         (not (file-directory-p dir-dst))
         (signal 'file-error
           (format "Error: file %s exist" dir-dst)))
       ;; if dir-dst does not exist - create it
       (if (not (file-exists-p dir-dst))
         (make-directory dir-dst))
       (dolist (file (directory-files dir-src))
         (and
           (not (string= file "."))
           (not (string= file ".."))
           (let ((path (concat dir-src "/" file)))
             (if (file-directory-p path)
               ;; it is a directory
               (progn
                 ;; place it to the queue
                 (setq queue
                   (cons
                     (cons path (concat dir-dst "/" file))
                     queue))
                 ;; and store it path to remove it later
                 (push path remove-later))
               ;; not a dir
               (progn
                 (message
                   (format "Moving %s to %s" path dir-dst))
                 (rename-file path dir-dst)))))))
   ;; after we moved all content we can remove the
   ;; empty directories in dir-src
   (dolist (dir remove-later)
     (condition-case err
       (dired-delete-file dir 'always)
       (error ;; catch errors from failed deletions
         (dired-log "%s\n" err)))))
   (dired-delete-file dir-src 'always))

Re: "Renaming: permission denied" file-error in Windows

[Eli Zaretskii]

> Date: Sun, 11 Dec 2011 02:16:45 +0200
> From: LynX <_LynX@bk.ru>
> 
> I found that dired in Windows does not provide you possibility to move a 
> directory to a new location if this new location resides on a different 
> logical disk.
> 
> For instance you have two opened dired buffers: `c:\dir1' and 
> `f:\dir2'. To move some files from `dir1' to `dir2' you can use "R", but 
> if you try to move some directory from `dir1' to `dir2' you will get 
> `Renaming: permission denied' error message.

Does Emacs on Unix or GNU/Linux systems allow moving a directory to a
different filesystem?  (I cannot test this where I'm typing this.)  If
not, the Windows behavior is not a bug.

> The problem occurs when dired calls Emacs function which delegates the 
> call to native POSIX function `rename'.
> 
> In Windows `rename' operates a bit different than in other systems. 
> According to MSDN [http://msdn.microsoft.com/en-us/library/zw5t957f.aspx]:

Emacs doesn't call `rename' from the MS library, it has its own
replacement `sys_rename'.  So if we decide to modify this behavior, we
can.

> -- "You can use rename to move a file from one directory or device to 
> another by giving a different path in the newname argument. However, you 
> cannot use rename to move a directory." --

But you _can_ rename or move a directory on MS-Windows, as long as the
destination is on the same drive.  Try it.

Re: "Renaming: permission denied" file-error in Windows

[Tekk]

On Sun, 11 Dec 2011, Eli Zaretskii wrote:

>> Date: Sun, 11 Dec 2011 02:16:45 +0200
>> From: LynX <_LynX@bk.ru>
>>
>> I found that dired in Windows does not provide you possibility to move a
>> directory to a new location if this new location resides on a different
>> logical disk.
>>
>> For instance you have two opened dired buffers: `c:\dir1' and
>> `f:\dir2'. To move some files from `dir1' to `dir2' you can use "R", but
>> if you try to move some directory from `dir1' to `dir2' you will get
>> `Renaming: permission denied' error message.
>
> Does Emacs on Unix or GNU/Linux systems allow moving a directory to a
> different filesystem?  (I cannot test this where I'm typing this.)  If
> not, the Windows behavior is not a bug.
>
>> The problem occurs when dired calls Emacs function which delegates the
>> call to native POSIX function `rename'.
>>
>> In Windows `rename' operates a bit different than in other systems.
>> According to MSDN [http://msdn.microsoft.com/en-us/library/zw5t957f.aspx]:
>
> Emacs doesn't call `rename' from the MS library, it has its own
> replacement `sys_rename'.  So if we decide to modify this behavior, we
> can.
>
>> -- "You can use rename to move a file from one directory or device to
>> another by giving a different path in the newname argument. However, you
>> cannot use rename to move a directory." --
>
> But you _can_ rename or move a directory on MS-Windows, as long as the
> destination is on the same drive.  Try it.
>
but that's not his issue, he filed the bug about not being able to move 
onto a different drive, not being unable to move at all.

Re: "Renaming: permission denied" file-error in Windows

[Eli Zaretskii]

> Date: Sun, 11 Dec 2011 00:32:36 -0500 (EST)
> From: Tekk <tekk@parlementum.net>
> cc: LynX <_LynX@bk.ru>, emacs-devel@gnu.org
> 
> >> -- "You can use rename to move a file from one directory or device to
> >> another by giving a different path in the newname argument. However, you
> >> cannot use rename to move a directory." --
> >
> > But you _can_ rename or move a directory on MS-Windows, as long as the
> > destination is on the same drive.  Try it.
> >
> but that's not his issue, he filed the bug about not being able to move 
> onto a different drive, not being unable to move at all.

I know, but I was referring to the part he cited (see above), that
tells you cannot rename or move a directory at all.  That is not true.

Re: "Renaming: permission denied" file-error in Windows

[Paul Eggert]

On 12/10/11 21:30, Eli Zaretskii wrote:
> Does Emacs on Unix or GNU/Linux systems allow moving a directory to a
> different filesystem?  (I cannot test this where I'm typing this.)

Yes it does.  Emacs first tries to rename the directory, and when that
fails (because rename fails with errno == EXDEV) it copies the
directory recursively.

> If not, the Windows behavior is not a bug.

Re: "Renaming: permission denied" file-error in Windows

[Eli Zaretskii]

> Date: Sun, 11 Dec 2011 00:32:33 -0800
> From: Paul Eggert <eggert@cs.ucla.edu>
> CC: LynX <_LynX@bk.ru>, emacs-devel@gnu.org
> 
> On 12/10/11 21:30, Eli Zaretskii wrote:
> > Does Emacs on Unix or GNU/Linux systems allow moving a directory to a
> > different filesystem?  (I cannot test this where I'm typing this.)
> 
> Yes it does.

Thanks.

> Emacs first tries to rename the directory, and when that
> fails (because rename fails with errno == EXDEV) it copies the
> directory recursively.

Ah, I see the problem now: the implementation of `rename' on Windows
does not return errno = EXDEV in that case, so the recursive copying
does not happen.

I encourage the OP to file a bug report (using "M-x report-emacs-bug")
about this.  It should be easy to fix this.

Re: "Renaming: permission denied" file-error in Windows

[Eli Zaretskii]

> Date: Sun, 11 Dec 2011 19:30:11 +0000
> From: LynX <_LynX@bk.ru>
> CC: Paul Eggert <eggert@cs.ucla.edu>, emacs-devel@gnu.org
> 
> So for Windows rename returns EACCES instead of EXDEV.

Yes.

> Maybe to fix it in Windows we need to check rename error code not only 
> for EXDEV but for EACCES also.

No, we should modify sys_rename (in w32.c) to return EXDEV in these
cases.

> > I encourage the OP to file a bug report (using "M-x report-emacs-bug")
> > about this.  It should be easy to fix this.
> >
> >
> 
> Sorry, what "OP" means? :)

"Original Poster".  That is, you.

Re: "Renaming: permission denied" file-error in Windows

[LynX]

On 12/11/2011 12:51 PM, Eli Zaretskii wrote:
> Ah, I see the problem now: the implementation of `rename' on Windows
> does not return errno = EXDEV in that case, so the recursive copying
> does not happen.

Oh, yes you are right :). Here is a simple c code which demonstrates this:

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>

int main(int argc, char* argv[])
{
     // in Windows path of course was a bit different :)
     int ret = rename("/media/c/toDel/test", "/media/g/Temp");
     perror("error");
     printf("ret %d errno %d\n", ret, errno);
     if (errno == EXDEV) {
         printf("EXDEV\n");
     } else if (errno == EACCES) {
         printf("EACCES\n");
     }
     while(1);
     return 0;
}

In Linux output is:
ret -1 errno 18
EXDEV

In Windows:
error: Permission denied
ret -1 errno 13
EACCES

So for Windows rename returns EACCES instead of EXDEV.

Maybe to fix it in Windows we need to check rename error code not only 
for EXDEV but for EACCES also.

>
> I encourage the OP to file a bug report (using "M-x report-emacs-bug")
> about this.  It should be easy to fix this.
>
>

Sorry, what "OP" means? :)

Regards,
LX

Re: "Renaming: permission denied" file-error in Windows

[Eli Zaretskii]

> Date: Sun, 11 Dec 2011 21:45:02 +0000
> From: LynX <_LynX@bk.ru>
> CC: eggert@cs.ucla.edu, emacs-devel@gnu.org
> 
> Thank you for you response.
> If you don't mind I would like to try to fix it.
> It just would take some time to prepare my environment to build Emacs.
> 
> Do I need to provide bug report in such case either?

It is better to do that, so that we have a record of the problem.

Thanks.

Re: "Renaming: permission denied" file-error in Windows

[LynX]

Dear Eli,

Thank you for you response.
If you don't mind I would like to try to fix it.
It just would take some time to prepare my environment to build Emacs.

Do I need to provide bug report in such case either?

Regards,
LX

On 12/11/2011 06:03 PM, Eli Zaretskii wrote:
>> Date: Sun, 11 Dec 2011 19:30:11 +0000
>> From: LynX<_LynX@bk.ru>
>> CC: Paul Eggert<eggert@cs.ucla.edu>, emacs-devel@gnu.org
>>
>> So for Windows rename returns EACCES instead of EXDEV.
>
> Yes.
>
>> Maybe to fix it in Windows we need to check rename error code not only
>> for EXDEV but for EACCES also.
>
> No, we should modify sys_rename (in w32.c) to return EXDEV in these
> cases.
>
>>> I encourage the OP to file a bug report (using "M-x report-emacs-bug")
>>> about this.  It should be easy to fix this.
>>>
>>>
>>
>> Sorry, what "OP" means? :)
>
> "Original Poster".  That is, you.
>
>

Re: "Renaming: permission denied" file-error in Windows

[LynX]

Dear Eli,

I've opened a bug report here:

10284: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=10284

Here is the patch for this issue (it is done for the latest source 
package emacs-23.3b.tar.bz2):

--- w32.c.orig	2011-11-26 05:20:20.000000000 +0200
+++ w32.c	2011-12-25 09:22:37.734375000 +0200
@@ -2857,6 +2857,8 @@
  {
    BOOL result;
    char temp[MAX_PATH];
+  int newname_dev;
+  int oldname_dev;

    /* MoveFile on Windows 95 doesn't correctly change the short file name
       alias in a number of circumstances (it is not easy to predict when
@@ -2873,6 +2875,9 @@

    strcpy (temp, map_w32_filename (oldname, NULL));

+  /* volume_info is set indirectly by map_w32_filename */
+  oldname_dev = volume_info.serialnum;
+
    if (os_subtype == OS_WIN95)
      {
        char * o;
@@ -2916,13 +2921,31 @@
       all the permutations of shared or subst'd drives, etc.)  */

    newname = map_w32_filename (newname, NULL);
+
+  /* volume_info is set indirectly by map_w32_filename */
+  newname_dev = volume_info.serialnum;
+
    result = rename (temp, newname);

    if (result < 0
-      && errno == EEXIST
-      && _chmod (newname, 0666) == 0
-      && _unlink (newname) == 0)
-    result = rename (temp, newname);
+      && errno == EEXIST)
+    {
+      if (_chmod (newname, 0666) != 0)
+	return result;
+      if (_unlink (newname) != 0)
+	return result;
+      result = rename (temp, newname);
+    }
+
+  /* The implementation of `rename' on Windows does not return
+     errno = EXDEV when you are moving a directory to a different
+     storage device (ex. logical disk). It returns EACCES
+     instead. So here we handle such situations and return EXDEV.   */
+
+  if (result < 0
+      && errno == EACCES
+      && newname_dev != oldname_dev)
+    errno = EXDEV;

    return result;
  }

Fix is done as you proposed:

>> Maybe to fix it in Windows we need to check rename error code not only
>> for EXDEV but for EACCES also.
>No, we should modify sys_rename (in w32.c) to return EXDEV in these
>cases.

I've tested it (Windows XP sp3) and was able to move the directories 
between different storage devices.

Regards,
LX

11.12.2011 23:31, Eli Zaretskii пишет:
>> Date: Sun, 11 Dec 2011 21:45:02 +0000
>> From: LynX<_LynX@bk.ru>
>> CC: eggert@cs.ucla.edu, emacs-devel@gnu.org
>>
>> Thank you for you response.
>> If you don't mind I would like to try to fix it.
>> It just would take some time to prepare my environment to build Emacs.
>>
>> Do I need to provide bug report in such case either?
>
> It is better to do that, so that we have a record of the problem.
>
> Thanks.
>
>

Re: "Renaming: permission denied" file-error in Windows

[Eli Zaretskii]

> Date: Sun, 25 Dec 2011 09:33:34 +0200
> From: LynX <_LynX@bk.ru>
> Cc: eggert@cs.ucla.edu, emacs-devel@gnu.org
> 
> Dear Eli,
> 
> I've opened a bug report here:
> 
> 10284: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=10284
> 
> Here is the patch for this issue (it is done for the latest source 
> package emacs-23.3b.tar.bz2):

I've redirected this discussion to the bug tracker,
10284@debbugs.gnu.org.

Please respond there, not here.