ldap_sync_init_refresh_and_persist(3) — Linux manual page


LDAP_SYNC(3)              Library Functions Manual              LDAP_SYNC(3)

NAME         top

       ldap_sync_init,                          ldap_sync_init_refresh_only,
       ldap_sync_init_refresh_and_persist, ldap_sync_poll - LDAP  sync  rou‐

LIBRARY         top

       OpenLDAP LDAP (libldap, -lldap)

SYNOPSIS         top

       #include <ldap.h>

       int ldap_sync_init(ldap_sync_t *ls, int mode);

       int ldap_sync_init_refresh_only(ldap_sync_t *ls);

       int ldap_sync_init_refresh_and_persist(ldap_sync_t *ls);

       int ldap_sync_poll(ldap_sync_t *ls);

       ldap_sync_t * ldap_sync_initialize(ldap_sync_t *ls);

       void ldap_sync_destroy(ldap_sync_t *ls, int freeit);

       typedef int (*ldap_sync_search_entry_f)(ldap_sync_t *ls,
              LDAPMessage *msg, struct berval *entryUUID,
              ldap_sync_refresh_t phase);

       typedef int (*ldap_sync_search_reference_f)(ldap_sync_t *ls,
              LDAPMessage *msg);

       typedef int (*ldap_sync_intermediate_f)(ldap_sync_t *ls,
              LDAPMessage *msg, BerVarray syncUUIDs,
              ldap_sync_refresh_t phase);

       typedef int (*ldap_sync_search_result_f)(ldap_sync_t *ls,
              LDAPMessage *msg, int refreshDeletes);

DESCRIPTION         top

       These routines provide an interface to the LDAP Content
       Synchronization operation (RFC 4533).  They require an ldap_sync_t
       structure to be set up with parameters required for various phases of
       the operation; this includes setting some handlers for special
       events.  All handlers take a pointer to the ldap_sync_t structure as
       the first argument, and a pointer to the LDAPMessage structure as
       received from the server by the client library, plus, occasionally,
       other specific arguments.

       The members of the ldap_sync_t structure are:

       char *ls_base
              The search base; by default, the BASE option in ldap.conf(5).

       int ls_scope
              The search scope (one of LDAP_SCOPE_BASE, LDAP_SCOPE_ONELEVEL,
              LDAP_SCOPE_SUBORDINATE or LDAP_SCOPE_SUBTREE; see ldap.h for

       char *ls_filter
              The filter (RFC 4515); by default, (objectClass=*).

       char **ls_attrs
              The requested attributes; by default NULL, indicating all user

       int ls_timelimit
              The requested time limit (in seconds); by default 0, to
              indicate no limit.

       int ls_sizelimit
              The requested size limit (in entries); by default 0, to
              indicate no limit.

       int ls_timeout
              The desired timeout during polling with ldap_sync_poll(3).  A
              value of -1 means that polling is blocking, so
              ldap_sync_poll(3) will not return until a message is received;
              a value of 0 means that polling returns immediately, no matter
              if any response is available or not; a positive value
              represents the timeout the ldap_sync_poll(3) function will
              wait for response before returning, unless a message is
              received; in that case, ldap_sync_poll(3) returns as soon as
              the message is available.

       ldap_sync_search_entry_f ls_search_entry
              A function that is called whenever an entry is returned.  The
              msg argument is the LDAPMessage that contains the
              searchResultEntry; it can be parsed using the regular client
              API routines, like ldap_get_dn(3), ldap_first_attribute(3),
              and so on.  The entryUUID argument contains the entryUUID of
              the entry.  The phase argument indicates the type of
              operation: one of LDAP_SYNC_CAPI_PRESENT, LDAP_SYNC_CAPI_ADD,
              is contained in the LDAPMessage; in case of
              LDAP_SYNC_CAPI_MODIFY, the whole entry is contained in the
              LDAPMessage, and the application is responsible of determining
              the differences between the new view of the entry provided by
              the caller and the data already known.

       ldap_sync_search_reference_f ls_search_reference
              A function that is called whenever a search reference is
              returned.  The msg argument is the LDAPMessage that contains
              the searchResultReference; it can be parsed using the regular
              client API routines, like ldap_parse_reference(3).

       ldap_sync_intermediate_f ls_intermediate
              A function that is called whenever something relevant occurs
              during the refresh phase of the search, which is marked by an
              intermediateResponse message type.  The msg argument is the
              LDAPMessage that contains the intermediate response; it can be
              parsed using the regular client API routines, like
              ldap_parse_intermediate(3).  The syncUUIDs argument contains
              an array of UUIDs of the entries that depends on the value of
              the phase argument.  In case of LDAP_SYNC_CAPI_PRESENTS, the
              "present" phase is being entered; this means that the
              following sequence of results will consist in entries in
              "present" sync state.  In case of LDAP_SYNC_CAPI_DELETES, the
              "deletes" phase is being entered; this means that the
              following sequence of results will consist in entries in
              "delete" sync state.  In case of
              LDAP_SYNC_CAPI_PRESENTS_IDSET, the message contains a set of
              UUIDs of entries that are present; it replaces a "presents"
              phase.  In case of LDAP_SYNC_CAPI_DELETES_IDSET, the message
              contains a set of UUIDs of entries that have been deleted; it
              replaces a "deletes" phase.  In case of LDAP_SYNC_CAPI_DONE, a
              "presents" phase with "refreshDone" set to "TRUE" has been
              returned to indicate that the refresh phase of
              refreshAndPersist is over, and the client should start
              polling.  Except for the LDAP_SYNC_CAPI_PRESENTS_IDSET and
              LDAP_SYNC_CAPI_DELETES_IDSET cases, syncUUIDs is NULL.

       ldap_sync_search_result_f ls_search_result
              A function that is called whenever a searchResultDone is
              returned.  In refreshAndPersist this can only occur when the
              server decides that the search must be interrupted.  The msg
              argument is the LDAPMessage that contains the response; it can
              be parsed using the regular client API routines, like
              ldap_parse_result(3).  The refreshDeletes argument is not
              relevant in this case; it should always be -1.

       void *ls_private
              A pointer to private data.  The client may register here a
              pointer to data the handlers above may need.

       LDAP *ls_ld
              A pointer to a LDAP structure that is used to connect to the
              server.  It is the responsibility of the client to initialize
              the structure and to provide appropriate authentication and
              security in place.

GENERAL USE         top

       A ldap_sync_t structure is initialized by calling
       ldap_sync_initialize(3).  This simply clears out the contents of an
       already existing ldap_sync_t structure, and sets appropriate values
       for some members.  After that, the caller is responsible for setting
       up the connection (member ls_ld), eventually setting up transport
       security (TLS), for binding and any other initialization.  The caller
       must also fill all the documented search-related fields of the
       ldap_sync_t structure.

       At the end of a session, the structure can be cleaned up by calling
       ldap_sync_destroy(3), which takes care of freeing all data assuming
       it was allocated by ldap_mem*(3) routines.  Otherwise, the caller
       should take care of destroying and zeroing out the documented search-
       related fields, and call ldap_sync_destroy(3) to free undocumented
       members set by the API.

REFRESH ONLY         top

       The refreshOnly functionality is obtained by periodically calling
       ldap_sync_init(3) with mode set to LDAP_SYNC_REFRESH_ONLY, or, which
       is equivalent, by directly calling ldap_sync_init_refresh_only(3).
       The state of the search, and the consistency of the search
       parameters, is preserved across calls by passing the ldap_sync_t
       structure as left by the previous call.


       The refreshAndPersist functionality is obtained by calling
       ldap_sync_init(3) with mode set to LDAP_SYNC_REFRESH_AND_PERSIST, or,
       which is equivalent, by directly calling
       ldap_sync_init_refresh_and_persist(3) and, after a successful return,
       by repeatedly polling with ldap_sync_poll(3) according to the desired

       A client may insert a call to ldap_sync_poll(3) into an external loop
       to check if any modification was returned; in this case, it might be
       appropriate to set ls_timeout to 0, or to set it to a finite, small
       value.  Otherwise, if the client's main purpose consists in waiting
       for responses, a timeout of -1 is most suitable, so that the function
       only returns after some data has been received and handled.

ERRORS         top

       All routines return any LDAP error resulting from a lower-level error
       in the API calls they are based on, or LDAP_SUCCESS in case of
       success.  ldap_sync_poll(3) may return LDAP_SYNC_REFRESH_REQUIRED if
       a full refresh is requested by the server.  In this case, it is
       appropriate to call ldap_sync_init(3) again, passing the same
       ldap_sync_t structure as resulted from any previous call.

NOTES         top

SEE ALSO         top

       ldap(3), ldap_search_ext(3), ldap_result(3); RFC 4533

AUTHOR         top

       Designed and implemented by Pierangelo Masarati, based on RFC 4533
       and loosely inspired by syncrepl code in slapd(8).


       Initially developed by SysNet s.n.c.  OpenLDAP is developed and
       maintained by The OpenLDAP Project (http://www.openldap.org/).
       OpenLDAP is derived from University of Michigan LDAP 3.3 Release.

COLOPHON         top

       This page is part of the OpenLDAP (an open source implementation of
       the Lightweight Directory Access Protocol) project.  Information
       about the project can be found at ⟨http://www.openldap.org/⟩.  If you
       have a bug report for this manual page, see
       ⟨http://www.openldap.org/its/⟩.  This page was obtained from the
       project's upstream Git repository
       ⟨https://git.openldap.org/openldap/openldap.git⟩ on 2020-09-18.  (At
       that time, the date of the most recent commit that was found in the
       repository was 2020-09-18.)  If you discover any rendering problems
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       of the original manual page), send a mail to man-pages@man7.org

OpenLDAP LDVERSION               RELEASEDATE                    LDAP_SYNC(3)

Pages that refer to this page: ldap_sync(3)ldap_sync_init(3)ldap_sync_init_refresh_and_persist(3)ldap_sync_init_refresh_only(3)ldap_sync_poll(3)