Tribblix: manual page: ldap

LDAP_MEMCACHE(3LDAP) LDAP Library Functions LDAP_MEMCACHE(3LDAP)

NAME

ldap_memcache, ldap_memcache_init, ldap_memcache_set,
ldap_memcache_get, ldap_memcache_flush, ldap_memcache_destroy,
ldap_memcache_update - LDAP client caching functions

SYNOPSIS

cc -flag ... file...-lldap [ -library ... ]
#include <ldap.h>

int ldap_memcache_init(unsigned long ttl, unsigned long size,
char **baseDNs,struct ldap_thread_fns *thread_fns,
LDAPMemCache **cachep

int ldap_memcache_set(LDAP *ld, LDAPMemCache **cache

int ldap_memcache_get(LDAP *ld, LDAPMemCache **cachep

void ldap_memcache_flush(LDAPMemCache *cache, char *dn, int scope

void ldap_memcache_destroy(LDAPMemCache *cache

void ldap_memcache_update(LDAPMemCache *cache

DESCRIPTION

Use the ldap_memcache functions to maintain an in-memory client side
cache to store search requests. Caching improves performance and
reduces network bandwidth when a client makes repeated requests. The
cache uses search criteria as the key to the cached items. When you
send a search request, the cache checks the search criteria to
determine if that request has been previously stored . If the request
was stored, the search results are read from the cache.

Make a call to ldap_memcache_init() to create the in-memory client
side cache. The function passes back a pointer to an LDAPMemCache
structure, which represents the cache. Make a call to the
ldap_memcache_set() function to associate this cache with an LDAP
connection handle, an LDAP structure. ttl is the maximum amount of
time (in seconds) that an item can be cached. If a ttl value of 0 is
passed, there is no limit to the amount of time that an item can be
cached. size is the maximum amount of memory (in bytes) that the
cache will consume. A zero value of size means the cache has no size
limit. baseDNS is an array of the base DN strings representing the
base DNs of the search requests you want cached. If baseDNS is not
NULL, only the search requests with the specified base DNs will be
cached. If baseDNS is NULL, all search requests are cached. The
thread_fns parameter takes an ldap_thread_fns structure specifying
the functions that you want used to ensure that the cache is thread-
safe. You should specify this if you have multiple threads that are
using the same connection handle and cache. If you are not using
multiple threads, pass NULL for this parameter.

ldap_memcache_set() associates an in-memory cache that you have
already created by calling the ldap_memcache_init() function with an
LDAP connection handle. The ld parameter should be the result of a
successful call to ldap_open(3LDAP). The cache parameter should be
the result of a cache created by the ldap_memcache_init() call.
After you call this function, search requests made over the specified
LDAP connection will use this cache. To disassociate the cache from
the LDAP connection handle, make a call to the ldap_bind(3LDAP) or
ldap_bind(3LDAP) function. Make a call to ldap_memcache_set() if you
want to associate a cache with multiple LDAP connection handles. For
example, call the ldap_memcache_get() function to get the cache
associated with one connection, then you can call this function and
associate the cache with another connection.

The ldap_memcache_get() function gets the cache associated with the
specified connection handle (LDAP structure). This cache is used by
all search requests made through that connection. When you call this
function, the function sets the cachep parameter as a pointer to the
LDAPMemCache structure that is associated with the connection handle.

ldap_memcache_flush() flushes search requests from the cache. If the
base DN of a search request is within the scope specified by the dn
and scope arguments, the search request is flushed from the cache.
If no DN is specified, the entire cache is flushed. The scope
parameter, along with the dn parameter, identifies the search
requests that you want flushed from the cache. This argument can have
one of the following values:
LDAP_SCOPE_BASE
LDAP_SCOPE_ONELEVEL
LDAP_SCOPE_SUBTREE

ldap_memcache_destroy() frees the specified LDAPMemCache structure
pointed to by cache from memory. Call this function after you are
done working with a cache.

ldap_memcache_update() checks the cache for items that have expired
and removes them. This check is typically done as part of the way the
cache normally works. You do not need to call this function unless
you want to update the cache at this point in time. This function is
only useful in a multithreaded application, since it will not return
until the cache is destroyed.

PARAMETERS

ttl
The maximum amount of time (in seconds) that an item
can be cached

size
The maximum amount of memory (in bytes) that the cache
will consume.

baseDNs
An array of the base DN strings representing the base
DNs of the search requests you want cached

thread_fns
A pointer to the ldap_thread_fns structure structure.

cachep
A pointer to the LDAPMemCache structure

cache
The result of a cache created by the
ldap_memcache_init() call

ld
The result of a successful call to ldap_open(3LDAP)

dn
The search requests that you want flushed from the
cache

scope
The search requests that you want flushed from the
cache

ERRORS

The functions that have int return values return LDAP_SUCCESS if the
operation was successful. Otherwise, they return another LDAP error
code. See ldap_error(3LDAP) for a list of the LDAP error codes.