LDAP_SCHEMA(3) OpenLDAP LDVERSION LDAP_SCHEMA(3)
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NAME
ldap_str2syntax, ldap_syntax2str, ldap_syntax2name, ldap_syntax_free,
ldap_str2matchingrule, ldap_matchingrule2str, ldap_matchingrule2name,
ldap_matchingrule_free, ldap_str2attributetype,
ldap_attributetype2str, ldap_attributetype2name,
ldap_attributetype_free, ldap_str2objectclass, ldap_objectclass2str,
ldap_objectclass2name, ldap_objectclass_free, ldap_scherr2str - Schema
definition handling routines
LIBRARY
OpenLDAP LDAP (libldap, -lldap)
SYNOPSIS
#include <ldap.h>
#include <ldap_schema.h>
LDAPSyntax * ldap_str2syntax(s, code, errp, flags)
const char * s;
int * code;
const char ** errp;
const int flags;
char * ldap_syntax2str(syn)
const LDAPSyntax * syn;
const char * ldap_syntax2name(syn)
LDAPSyntax * syn;
ldap_syntax_free(syn)
LDAPSyntax * syn;
LDAPMatchingRule * ldap_str2matchingrule(s, code, errp, flags)
const char * s;
int * code;
const char ** errp;
const int flags;
char * ldap_matchingrule2str(mr);
const LDAPMatchingRule * mr;
const char * ldap_matchingrule2name(mr)
LDAPMatchingRule * mr;
ldap_matchingrule_free(mr)
LDAPMatchingRule * mr;
LDAPAttributeType * ldap_str2attributetype(s, code, errp, flags)
const char * s;
int * code;
const char ** errp;
const int flags;
char * ldap_attributetype2str(at)
const LDAPAttributeType * at;
const char * ldap_attributetype2name(at)
LDAPAttributeType * at;
ldap_attributetype_free(at)
LDAPAttributeType * at;
LDAPObjectClass * ldap_str2objectclass(s, code, errp, flags)
const char * s;
int * code;
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LDAP_SCHEMA(3) OpenLDAP LDVERSION LDAP_SCHEMA(3)
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const char ** errp;
const int flags;
char * ldap_objectclass2str(oc)
const LDAPObjectClass * oc;
const char * ldap_objectclass2name(oc)
LDAPObjectClass * oc;
ldap_objectclass_free(oc)
LDAPObjectClass * oc;
char * ldap_scherr2str(code)
int code;
DESCRIPTION
These routines are used to parse schema definitions in the syntax
defined in RFC 4512 into structs and handle these structs. These
routines handle four kinds of definitions: syntaxes, matching rules,
attribute types and object classes. For each definition kind, four
routines are provided. ldap_str2xxx() takes a definition in RFC 4512
format in argument s as a NUL-terminated string and returns, if
possible, a pointer to a newly allocated struct of the appropriate
kind. The caller is responsible for freeing the struct by calling
ldap_xxx_free() when not needed any longer. The routine returns NULL
if some problem happened. In this case, the integer pointed at by
argument code will receive an error code (see below the description of
ldap_scherr2str() for an explanation of the values) and a pointer to a
NUL-terminated string will be placed where requested by argument errp
, indicating where in argument s the error happened, so it must not be
freed by the caller. Argument flags is a bit mask of parsing options
controlling the relaxation of the syntax recognized. The following
values are defined:
LDAP_SCHEMA_ALLOW_NONE
strict parsing according to RFC 4512.
LDAP_SCHEMA_ALLOW_NO_OID
permit definitions that do not contain an initial OID.
LDAP_SCHEMA_ALLOW_QUOTED
permit quotes around some items that should not have them.
LDAP_SCHEMA_ALLOW_DESCR
permit a descr instead of a numeric OID in places where the
syntax expect the latter.
LDAP_SCHEMA_ALLOW_DESCR_PREFIX
permit that the initial numeric OID contains a prefix in descr
format.
LDAP_SCHEMA_ALLOW_ALL
be very liberal, include all options. The structures returned
are as follows:
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LDAP_SCHEMA(3) OpenLDAP LDVERSION LDAP_SCHEMA(3)
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typedef struct ldap_schema_extension_item {
char *lsei_name; /* Extension name */
char **lsei_values; /* Extension values */
} LDAPSchemaExtensionItem;
typedef struct ldap_syntax {
char *syn_oid; /* OID */
char **syn_names; /* Names */
char *syn_desc; /* Description */
LDAPSchemaExtensionItem **syn_extensions; /* Extension */
} LDAPSyntax;
typedef struct ldap_matchingrule {
char *mr_oid; /* OID */
char **mr_names; /* Names */
char *mr_desc; /* Description */
int mr_obsolete; /* Is obsolete? */
char *mr_syntax_oid; /* Syntax of asserted values */
LDAPSchemaExtensionItem **mr_extensions; /* Extensions */
} LDAPMatchingRule;
typedef struct ldap_attributetype {
char *at_oid; /* OID */
char **at_names; /* Names */
char *at_desc; /* Description */
int at_obsolete; /* Is obsolete? */
char *at_sup_oid; /* OID of superior type */
char *at_equality_oid; /* OID of equality matching rule */
char *at_ordering_oid; /* OID of ordering matching rule */
char *at_substr_oid; /* OID of substrings matching rule */
char *at_syntax_oid; /* OID of syntax of values */
int at_syntax_len; /* Suggested minimum maximum length */
int at_single_value; /* Is single-valued? */
int at_collective; /* Is collective? */
int at_no_user_mod; /* Are changes forbidden through LDAP? */
int at_usage; /* Usage, see below */
LDAPSchemaExtensionItem **at_extensions; /* Extensions */
} LDAPAttributeType;
typedef struct ldap_objectclass {
char *oc_oid; /* OID */
char **oc_names; /* Names */
char *oc_desc; /* Description */
int oc_obsolete; /* Is obsolete? */
char **oc_sup_oids; /* OIDs of superior classes */
int oc_kind; /* Kind, see below */
char **oc_at_oids_must; /* OIDs of required attribute types */
char **oc_at_oids_may; /* OIDs of optional attribute types */
LDAPSchemaExtensionItem **oc_extensions; /* Extensions */
} LDAPObjectClass;
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LDAP_SCHEMA(3) OpenLDAP LDVERSION LDAP_SCHEMA(3)
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Some integer fields (those described with a question mark) have a
truth value, for these fields the possible values are:
LDAP_SCHEMA_NO
The answer to the question is no.
LDAP_SCHEMA_YES
The answer to the question is yes. For attribute types, the
following usages are possible:
LDAP_SCHEMA_USER_APPLICATIONS
the attribute type is non-operational.
LDAP_SCHEMA_DIRECTORY_OPERATION
the attribute type is operational and is pertinent to the
directory itself, i.e. it has the same value on all servers that
provide the entry containing this attribute type.
LDAP_SCHEMA_DISTRIBUTED_OPERATION
the attribute type is operational and is pertinent to
replication, shadowing or other distributed directory aspect.
TBC.
LDAP_SCHEMA_DSA_OPERATION
the attribute type is operational and is pertinent to the
directory server itself, i.e. it may have different values for
the same entry when retrieved from different servers that provide
the entry. Object classes can be of three kinds:
LDAP_SCHEMA_ABSTRACT
the object class is abstract, i.e. there cannot be entries of
this class alone.
LDAP_SCHEMA_STRUCTURAL
the object class is structural, i.e. it describes the main role
of the entry. On some servers, once the entry is created the set
of structural object classes assigned cannot be changed: none of
those present can be removed and none other can be added.
LDAP_SCHEMA_AUXILIARY
the object class is auxiliary, i.e. it is intended to go with
other, structural, object classes. These can be added or removed
at any time if attribute types are added or removed at the same
time as needed by the set of object classes resulting from the
operation. Routines ldap_xxx2name() return a canonical name for
the definition. Routines ldap_xxx2str() return a string
representation in the format described by RFC 4512 of the struct
passed in the argument. The string is a newly allocated string
that must be freed by the caller. These routines may return NULL
if no memory can be allocated for the string. ldap_scherr2str()
returns a NUL-terminated string with a text description of the
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LDAP_SCHEMA(3) OpenLDAP LDVERSION LDAP_SCHEMA(3)
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error found. This is a pointer to a static area, so it must not
be freed by the caller. The argument code comes from one of the
parsing routines and can adopt the following values:
LDAP_SCHERR_OUTOFMEM
Out of memory.
LDAP_SCHERR_UNEXPTOKEN
Unexpected token.
LDAP_SCHERR_NOLEFTPAREN
Missing opening parenthesis.
LDAP_SCHERR_NORIGHTPAREN
Missing closing parenthesis.
LDAP_SCHERR_NODIGIT
Expecting digit.
LDAP_SCHERR_BADNAME
Expecting a name.
LDAP_SCHERR_BADDESC
Bad description.
LDAP_SCHERR_BADSUP
Bad superiors.
LDAP_SCHERR_DUPOPT
Duplicate option.
LDAP_SCHERR_EMPTY
Unexpected end of data.
SEE ALSO
ldap(3)
ACKNOWLEDGEMENTS
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