LBER_SOCKBUF(3)

💖 LBER_SOCKBUF(3) 💖

okay so bestie, welcome to LBER_SOCKBUF(3) — the Library Functions Manual page for OpenLDAP LBER I/O infrastructure. ✨ This one is all about the low-level I/O glow-up, and we're gonna get into it, no cap. 🫶

🌸 NAME 🌸

ber_sockbuf_alloc, ber_sockbuf_free, ber_sockbuf_ctrl, ber_sockbuf_add_io, ber_sockbuf_remove_io, Sockbuf_IO — OpenLDAP LBER I/O infrastructure. 💅

🫶 LIBRARY 🫶

OpenLDAP LBER (liblber, -llber). 🎀

✨ SYNOPSIS ✨

#include <lber.h>

Sockbuf *ber_sockbuf_alloc( void );

void ber_sockbuf_free(Sockbuf *sb);

int ber_sockbuf_ctrl(Sockbuf *sb, int opt, void *arg);

int ber_sockbuf_add_io(Sockbuf *sb, Sockbuf_IO *sbio, int layer, void
*arg);

int ber_sockbuf_remove_io(Sockbuf *sb, Sockbuf_IO *sbio, int layer);

typedef struct sockbuf_io_desc {
int sbiod_level;
Sockbuf *sbiod_sb;
Sockbuf_IO *sbiod_io;
void *sbiod_pvt;
struct sockbuf_io_desc *sbiod_next;
} Sockbuf_IO_Desc;

typedef struct sockbuf_io {
int (*sbi_setup)(Sockbuf_IO_Desc *sbiod, void *arg);
int (*sbi_remove)(Sockbuf_IO_Desc *sbiod);
int (*sbi_ctrl)(Sockbuf_IO_Desc *sbiod, int opt, void *arg);
ber_slen_t (*sbi_read)(Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len);
ber_slen_t (*sbi_write)(Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len);
int (*sbi_close)(Sockbuf_IO_Desc *sbiod);
} Sockbuf_IO;

💖 DESCRIPTION 💖

These routines are the low-level I/O glue for the Lightweight BER library. They get called implicitly by the other libraries, and usually you do not need to call them directly from applications. 😌 The I/O framework is modularized, and new transport layers can be supported by appropriately defining a Sockbuf_IO structure and installing it onto an existing Sockbuf. 🧚

Sockbuf structures are allocated and freed by ber_sockbuf_alloc() and ber_sockbuf_free(), respectively. The ber_sockbuf_ctrl() function is used to get and set options related to a Sockbuf or to a specific I/O layer of the Sockbuf. The ber_sockbuf_add_io() and ber_sockbuf_remove_io() functions are used to add and remove specific I/O layers on a Sockbuf. ✨

🎀 Options for ber_sockbuf_ctrl() 🎀

Options for ber_sockbuf_ctrl() include:

• LBER_SB_OPT_HAS_IO — takes a Sockbuf_IO * argument and returns 1 if the given handler is installed on the Sockbuf, otherwise returns 0. 💅
• LBER_SB_OPT_GET_FD — retrieves the file descriptor associated to the Sockbuf; arg must be a ber_socket_t *. The return value will be 1 if a valid descriptor was present, -1 otherwise. 🦋
• LBER_SB_OPT_SET_FD — sets the file descriptor of the Sockbuf to the descriptor pointed to by arg; arg must be a ber_socket_t *. The return value will always be 1. ✨
• LBER_SB_OPT_SET_NONBLOCK — toggles the non-blocking state of the file descriptor associated to the Sockbuf. arg should be NULL to disable and non-NULL to enable the non-blocking state. The return value will be 1 for success, -1 otherwise. 🎀
• LBER_SB_OPT_DRAIN — flush (read and discard) all available input on the Sockbuf. The return value will be 1. 💖
• LBER_SB_OPT_NEEDS_READ — returns non-zero if input is waiting to be read. 👑
• LBER_SB_OPT_NEEDS_WRITE — returns non-zero if the Sockbuf is ready to be written. 🌈
• LBER_SB_OPT_GET_MAX_INCOMING — returns the maximum allowed size of an incoming message; arg must be a ber_len_t *. The return value will be 1. 🍓
• LBER_SB_OPT_SET_MAX_INCOMING — sets the maximum allowed size of an incoming message; arg must be a ber_len_t *. The return value will be 1. 🧚

Options not in this list will be passed down to each Sockbuf_IO handler in turn until one of them processes it. If the option is not handled, ber_sockbuf_ctrl() will return 0. 💀

Multiple Sockbuf_IO handlers can be stacked in multiple layers to provide various functionality. Currently defined layers include:

🦋 Layers 🦋

• LBER_SBIOD_LEVEL_PROVIDER — the lowest layer, talking directly to a network. 🌐
• LBER_SBIOD_LEVEL_TRANSPORT — an intermediate layer. 🚀
• LBER_SBIOD_LEVEL_APPLICATION — a higher layer. 👑

🌈 Sockbuf_IO handlers 🌈

Currently defined Sockbuf_IO handlers in liblber include:

• ber_sockbuf_io_tcp — the default stream-oriented provider. 💅
• ber_sockbuf_io_fd — a stream-oriented provider for local IPC sockets. 🔌
• ber_sockbuf_io_dgram — a datagram-oriented provider. This handler is only present if the liblber library was built with LDAP_CONNECTIONLESS defined. 📦
• ber_sockbuf_io_readahead — a buffering layer, usually used with a datagram provider to hide the datagram semantics from upper layers. 🧚
• ber_sockbuf_io_debug — a generic handler that outputs hex dumps of all traffic. This handler may be inserted multiple times at arbitrary layers to show the flow of data between other handlers. 🔍

💜 Additional handlers in libldap 💜

Additional handlers may be present in libldap if support for them was enabled:

• ldap_pvt_sockbuf_io_sasl — an application layer handler for SASL encoding/decoding. 🎀
• sb_tls_sbio — a transport layer handler for SSL/TLS encoding/decoding. Note that this handler is private to the library and is not exposed in the API. 🔒

The provided handlers are all instantiated implicitly by libldap, and applications generally will not need to directly manipulate them. 🫶

👑 SEE ALSO 👑

lber-decode(3), lber-encode(3), lber-types(3), ldap_get_option(3)

💜 ACKNOWLEDGEMENTS 💜

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. 🫶

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okay that's the whole page, bestie! 💖 This one's from OpenLDAP 2.6.16, dated 2026/10/21, and the manual tag is LBER_SOCKBUF(3) — periodt. 🎀✨