DS error logs throwing "posix_winsync_end_update_cb: failed to add task entry"
error.

Steps to Reproduce:
1. Install latest 389-ds-base packages and configure Winsync.
2. Enable "Posix Winsync" plugin and set these
values(posixWinsyncCreateMemberOfTask and posixwinsyncmapmemberuid) TRUE.
3. Add few groups on AD with member attribute.
4. Leave the setup for 5 - 10 mins
5. Add few more groups on to AD with member attribute.
6. Tail the DS error logs and observe any error messages displayed as
"posix-winsync - posix_winsync_end_update_cb: failed to add task entry"

Actual results: It throws "posix-winsync - posix_winsync_end_update_cb: failed
to add task entry"

Expected results:
There should be a better way to handle if the task is already running/exists.

Additional info: Noriko's comments:

Investigated a little more on this issue. I think the error is minor and we
could fix it in 1.3.1. But, I'd like to have more comments...

The error message is issued when testing this functionality:

posixWinsyncCreateMemberOfTask - this is FALSE by default. Set this to TRUE

if you are using memberOf and you want the memberOf attribute values updated
after group sync is complete. The plugin will invoke the memberof fixup task to
perform this update.

The Posix Winsync plugin sets the config parameter:

dn: cn=Posix Winsync API,cn=plugins,cn=config
posixwinsynccreatememberoftask: TRUE

slapd-M1/dse.ldif has the "memberuid task" entry:

dn: cn=memberuid task,cn=tasks,cn=config
objectClass: top
objectClass: extensibleObject
cn: memberuid task
creatorsName: cn=server,cn=plugins,cn=config
modifiersName: cn=server,cn=plugins,cn=config
createTimestamp: 20130225103003Z
modifyTimestamp: 20130225103003Z

And the real task entry is added sometimes. It's added periodically and let
the task run, then the task disappears when it's done.

dn: cn=posix-winsync,cn=memberuid task,cn=tasks,cn=config
cn: posix-winsync
objectClass: extensibleObject
objectClass: top
basedn: ou=dswinsync,dc=passsync,dc=com
creatorsName: cn=Posix Winsync API,cn=plugins,cn=config
modifiersName: cn=Posix Winsync API,cn=plugins,cn=config
createTimestamp: 20130225191505Z
modifyTimestamp: 20130225191505Z

The error "failed to add task entry" is being issued in the function
"posix_winsync_end_update_cb" as we see in the error log:

[25/Feb/2013:05:33:10 -0500] posix-winsync - posix_winsync_end_update_cb:

failed to add task entry
[25/Feb/2013:05:35:06 -0500] posix-winsync - posix_winsync_end_update_cb:
failed to add task entry
[25/Feb/2013:05:36:31 -0500] posix-winsync - posix_winsync_end_update_cb:
failed to add task entry
[25/Feb/2013:05:36:32 -0500] posix-winsync - posix_winsync_end_update_cb:
failed to add task entry

The function adds the task entry which DN is always
"cn=posix-winsync,cn=memberuid task,cn=tasks,cn=config"
char *dn = slapi_create_dn_string("cn=%s,cn=%s,cn=tasks,cn=config",
posix_winsync_plugin_name, MEMBEROFTASK);

The function posix_winsync_end_update_cb is a update callback, if multiple
updates come in while the first task is still running, the additional task adds
fail since all tasks share the same name...? Probably, we want to set the
different name, e.g., containing the time stamp in the cn
(cn=posix-winsync-<time>,cn=memberuid task,cn=tasks,cn=config")?

But it may not be needed that intensively if the purpose of the task is just
"fix_memberuid scan for orphaned memberuids" under the basedn
"ou=dswinsync,dc=passsync,dc=com". If that's the case, the above error would
be benign. We may want to suppress them if the error code is
LDAP_ALREADY_EXISTS.

Thanks,
--noriko