[Samba] vfs_shadow_copy2 delimiter not working

[Michael Miller]

Hi

Thank you for your reply. It is very much appreciated.

I have recompiled the source (without my patch) and when the 
shadow:delimiter is included within the shadow:format Samba does work as 
expected. This is consistent with the code which I patched.

However - this configuration appears to contradict the man page for 
vfs_shadow which states:

        shadow:delimiter
            This optional parameter is used as a delimiter between
            shadow:snapprefix and shadow:format. This parameter is used only
            when shadow:snapprefix is set.


It states that the delimiter is the parameter *between* the snapprefix 
and format. The way it is written, I did not understand it to mean that 
the delimiter needs to be included within the format parameter.

If the wording is considered to be correct (which I don't) then I would 
suggest that an example is included within the man page which clearly 
shows the usage of the snapprefix, delimiter and format options when 
used together.

Maybe something like:

   shadow:snapprefix = ^\(monthly\)\{0,1\}\(daily\)\{0,1\}$
   shadow:delimiter = _UTC_
   shadow:format = _UTC_%Y.%m.%d-%H.%M.%S

as an example which would include the following directories:

daily_UTC_2017.02.05-01.00.01
monthly_UTC_2017.02.02-01.00.01
monthly_UTC_2017.02.03-01.00.01

and not

weekly_UTC_2017.02.04-01.00.0

Thanks again - your assistance is appreciated as it means I don't need 
to try and submit a patch or maintain a separate patched version of Samba :)

Kind regards,

Mike

On 19/04/2017 07:14, Anoop C S via samba wrote:
> On Sun, 2017-04-02 at 22:42 +0100, Michael Miller via samba wrote:
>> Hi
>>
>> I could not get a custom "shadow:delimiter" for the vfs shadow_copy2
>> module to work successfully for me with Samba 4.6.2. I did not try
>> previous versions. Based on my testing it seems that an additional line
>> of code is needed in vfs_shadow_copy2.c as shown in the patch below
>> (some comment updates are included too for code readability).
>>
>> Without the below patch, previous versions were not being returned by
>> Samba when using a shadow:delimiter. I was using a sample config of
>>
>> shadow:snapprefix = ^Snap
>> shadow:delimiter = _._
>> shadow:format = %Y.%m.%d-%H.%M.%S
>>
> I think you missed to specify delimiter in format parameter for shadow_copy2 module as below:
>
> shadow:format = _._%Y.%m.%d-%H.%M.%S
>
> If its still not working, can you please share me the logs(with log level 10) so as to debug the
> issue?
>
>> with sample snapshots named:
>> Snap_testing1_._2016.11.01-01.00.01
>> Snap_prerelease_._2016.12.01-01.00.02
>> Snap_postrelease_._2017.01.01-01.00.01
>>
>> Is anyone able to use a custom shadow:delimiter successfully without any
>> modifications to the Samba code? If not, how do I go about getting this
>> patch applied?
>>
>>
>> diff -up vfs_shadow_copy2.c.orig vfs_shadow_copy2.c
>> --- vfs_shadow_copy2.c.orig     2017-03-31 14:53:38.722560396 +0100
>> +++ vfs_shadow_copy2.c  2017-04-02 22:13:41.943038415 +0100
>> @@ -1866,16 +1866,19 @@ static bool shadow_copy2_snapshot_to_gmt
>>            */
>>           if (priv->snaps->regex != NULL) {
>>                   tmpstr = talloc_strdup(talloc_tos(), name);
>> -               /* point "name" to the time format */
>> +               /* Point "name" at <delimiter><time_format> */
>>                   name = strstr(name, priv->config->delimiter);
>>                   if (name == NULL) {
>>                           goto done;
>>                   }
>> -               /* Extract the prefix */
>> +               /* Now point name at <time_format> */
>> +                name = name + strlen(priv->config->delimiter);
>> +               /* Locate the the prefix */
>>                   tmp = strstr(tmpstr, priv->config->delimiter);
>>                   if (tmp == NULL) {
>>                           goto done;
>>                   }
>> +               /* Trim <delimiter><time_format> from tmpstr leaving
>> prefix */
>>                   *tmp = '\0';
>>
>>                   /* Parse regex */
>>