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   ber_sockbuf_remove_io    ( 3 )

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Имя (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

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Библиотека (Library)

OpenLDAP LBER (liblber, -llber)

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Синопсис (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;

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Описание (Description)

These routines are used to manage the low level I/O operations
       performed by the Lightweight BER library. They are called
       implicitly by the other libraries and usually do not need to be
       called 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() 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

       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

       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 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.

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Смотри также (See also)

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

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