LBER_TYPES(3)

πŸ’– LBER_TYPES πŸ’–

okay so bestie, this is a page from the Library Functions Manual, and it's literally all about the OpenLDAP LBER types and allocation functions. yes, all of them. buckle up πŸŽ€

✨ NAME ✨

ber_int_t, ber_uint_t, ber_len_t, ber_slen_t, ber_tag_t, struct berval, BerValue, BerVarray, BerElement, ber_bvfree, ber_bvecfree, ber_bvecadd, ber_bvarray_free, ber_bvarray_add, ber_bvdup, ber_dupbv, ber_bvstr, ber_bvstrdup, ber_str2bv, ber_alloc_t, ber_init, ber_init2, ber_free β€” OpenLDAP LBER types and allocation functions 🫢

πŸ“š LIBRARY πŸ“š

OpenLDAP LBER (liblber, -llber)

πŸ”₯ SYNOPSIS πŸ”₯

#include <lber.h>

typedef impl_tag_t ber_tag_t;
typedef impl_int_t ber_int_t;
typedef impl_uint_t ber_uint_t;
typedef impl_len_t ber_len_t;
typedef impl_slen_t ber_slen_t;

typedef struct berval {
    ber_len_t bv_len;
    char *bv_val;
} BerValue, *BerVarray;

typedef struct berelement BerElement;

void ber_bvfree(struct berval *bv);

void ber_bvecfree(struct berval **bvec);

void ber_bvecadd(struct berval ***bvec, struct berval *bv);

void ber_bvarray_free(struct berval *bvarray);

void ber_bvarray_add(BerVarray *bvarray, BerValue *bv);

struct berval *ber_bvdup(const struct berval *bv);

struct berval *ber_dupbv(const struct berval *dst, struct berval *src);

struct berval *ber_bvstr(const char *str);

struct berval *ber_bvstrdup(const char *str);

struct berval *ber_str2bv(const char *str, ber_len_t len, int dup,
struct berval *bv);

BerElement *ber_alloc_t(int options);

BerElement *ber_init(struct berval *bv);

void ber_init2(BerElement *ber, struct berval *bv, int options);

void ber_free(BerElement *ber, int freebuf);

🌸 DESCRIPTION 🌸

these are the basic types and structures defined for use with the Lightweight BER library. the whole squad. let's go through them one by one πŸ’…

ber_int_t is a signed integer of at least 32 bits. it's commonly equivalent to int. and ber_uint_t is the unsigned variant of ber_int_t.

ber_len_t is an unsigned integer of at least 32 bits used to represent a length. it's commonly equivalent to a size_t. ber_slen_t is the signed variant to ber_len_t.

ber_tag_t is an unsigned integer of at least 32 bits used to represent a BER tag. it's commonly equivalent to a unsigned long.

the actual definitions of the integral impl_TYPE_t types are platform specific πŸ‘€ so like, don't assume, bestie.


BerValue, commonly used as struct berval, is used to hold an arbitrary sequence of octets. bv_val points to bv_len octets. and listen β€” bv_val is not necessarily terminated by a NULL (zero) octet. so do not go treating it like a C string, i'm begging 😭

  • ber_bvfree() β€” frees a BerValue, pointed to by bv, returned from this API. if bv is NULL, the routine does nothing. iconique, no crash energy.
  • ber_bvecfree() β€” frees an array of BerValues (and the array), pointed to by bvec, returned from this API. if bvec is NULL, the routine does nothing.
  • ber_bvecadd() β€” appends the bv pointer to the bvec array. space for the array is allocated as needed. the end of the array is marked by a NULL pointer.
  • ber_bvarray_free() β€” frees an array of BerValues (and the array), pointed to by bvarray, returned from this API. if bvarray is NULL, the routine does nothing.
  • ber_bvarray_add() β€” appends the contents of the BerValue pointed to by bv to the bvarray array. space for the new element is allocated as needed. the end of the array is marked by a BerValue with a NULL bv_val field.

πŸ¦‹ copying stuff around πŸ¦‹

ber_bvdup() returns a copy of a BerValue. the routine returns NULL upon error (e.g. out of memory). the caller should use ber_bvfree() to deallocate the resulting BerValue.

ber_dupbv() copies a BerValue from src to dst. if dst is NULL a new BerValue will be allocated to hold the copy. the routine returns NULL upon error, otherwise it returns a pointer to the copy. if dst is NULL the caller should use ber_bvfree() to deallocate the resulting BerValue, otherwise ber_memfree() should be used to deallocate the dst->bv_val.

ngl the memory-freeing rules here are giving "two different cleanup paths" and if you mix them up it's gonna be a bad time πŸ’€ ber_bvdup() is internally implemented as ber_dupbv(NULL, bv). ber_bvdup() is provided only for compatibility with an expired draft of the LDAP C API β€” ber_dupbv() is the preferred interface. periodt.

🧚 string-flavoured BerValues 🧚

ber_bvstr() returns a BerValue containing the string pointed to by str. ber_bvstrdup() returns a BerValue containing a copy of the string pointed to by str.

ber_str2bv() returns a BerValue containing the string pointed to by str, whose length may be optionally specified in len. if dup is non-zero, the BerValue will contain a copy of str. if len is zero, the number of bytes to copy will be determined by strlen(3), otherwise len bytes will be copied. if bv is non-NULL, the result will be stored in the given BerValue, otherwise a new BerValue will be allocated to store the result.

NOTE: both ber_bvstr() and ber_bvstrdup() are implemented as macros using ber_str2bv() in this version of the library. so like, they're not real functions, they're macros πŸ’…

πŸ‘‘ BerElement, the mysterious one πŸ‘‘

BerElement is an opaque structure used to maintain state information used in encoding and decoding. main character energy, honestly.

  • ber_alloc_t() β€” used to create an empty BerElement structure. if LBER_USE_DER is specified for the options parameter then data lengths for data written to the BerElement will be encoded in the minimal number of octets required, otherwise they will always be written as four byte values.
  • ber_init() β€” creates a BerElement structure that is initialized with a copy of the data in its bv parameter.
  • ber_init2() β€” initializes an existing BerElement ber using the data in the bv parameter. the data is referenced directly, not copied. the options parameter is the same as for ber_alloc_t().
  • ber_free() β€” frees a BerElement pointed to by ber. if ber is NULL, the routine does nothing. if freebuf is zero, the internal buffer is not freed.
ok but the ber_init() vs ber_init2() difference is so important β€” one copies, one does not πŸ’€ don't come for me when your buffer goes out of scope, i warned you 😭

🌈 SEE ALSO 🌈

lber-encode(3), lber-decode(3), lber-memory(3)

πŸ’œ ACKNOWLEDGEMENTS πŸ’œ

OpenLDAP Software is developed and maintained by The OpenLDAP Project <http://www.openldap.org/>. OpenLDAP Software is derived from the University of Michigan LDAP 3.3 Release.


okay that's the whole page bestie, go forth and encode πŸ¦‹πŸ’–

OpenLDAP 2.6.16 β€” dated 2026/10/21 β€” that's the version and date, mwah, slay, goodbye πŸ‘‘βœ¨

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