.\" $OpenBSD: BIO_get_data.3,v 1.3 2018/03/23 23:18:17 schwarze Exp $ .\" selective merge up to: OpenSSL e90fc053 Jul 15 09:39:45 2017 -0400 .\" .\" This file is a derived work. .\" The changes are covered by the following Copyright and license: .\" .\" Copyright (c) 2018 Ingo Schwarze .\" .\" Permission to use, copy, modify, and distribute this software for any .\" purpose with or without fee is hereby granted, provided that the above .\" copyright notice and this permission notice appear in all copies. .\" .\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES .\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF .\" MERCHANTABILITY AND FITNESS. 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IN NO EVENT SHALL THE OpenSSL PROJECT OR .\" ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, .\" SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT .\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; .\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, .\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED .\" OF THE POSSIBILITY OF SUCH DAMAGE. .\" .Dd $Mdocdate: March 23 2018 $ .Dt BIO_GET_DATA 3 .Os .Sh NAME .Nm BIO_set_data , .Nm BIO_get_data , .Nm BIO_set_init , .Nm BIO_set_shutdown , .Nm BIO_get_shutdown .Nd manage BIO state information .Sh SYNOPSIS .In openssl/bio.h .Ft void .Fo BIO_set_data .Fa "BIO *a" .Fa "void *ptr" .Fc .Ft void * .Fo BIO_get_data .Fa "BIO *a" .Fc .Ft void .Fo BIO_set_init .Fa "BIO *a" .Fa "int init" .Fc .Ft void .Fo BIO_set_shutdown .Fa "BIO *a" .Fa "int shutdown" .Fc .Ft int .Fo BIO_get_shutdown .Fa "BIO *a" .Fc .Sh DESCRIPTION These functions are mainly useful when implementing a custom BIO. .Pp The .Fn BIO_set_data function associates the custom data pointed to by .Fa ptr with the .Fa "BIO a" . This data can subsequently be retrieved via a call to .Fn BIO_get_data . This can be used by custom BIOs for storing implementation specific information. .Pp The .Fn BIO_set_init function sets the .Fa init flag in .Fa a to the specified value. A non-zero value indicates that initialisation is complete, whilst zero indicates that it is not. Often initialisation will complete during initial construction of the BIO. For some BIOs however, initialisation may not be complete until additional steps have been taken, for example through calling custom ctrls. .Pp The .Fn BIO_set_shutdown and .Fn BIO_get_shutdown functions are low-level interfaces to forcefully set and get the .Fa shutdown flag of .Fa a , circumventing type-dependent sanity checks, exclusively intended for implementing a new BIO type. The .Fa shutdown argument must be either .Dv BIO_CLOSE or .Dv BIO_NOCLOSE . When merely using a .Vt BIO object, call .Xr BIO_set_close 3 and .Xr BIO_get_close 3 instead. .Sh RETURN VALUES .Fn BIO_get_data returns a pointer to the implementation specific custom data associated with .Fa a , or .Dv NULL if none is set. .Pp .Fn BIO_get_shutdown returns the value previously set with .Fn BIO_set_shutdown or with .Xr BIO_set_close 3 . .Sh SEE ALSO .Xr BIO_meth_new 3 , .Xr BIO_new 3 , .Xr BIO_set_close 3 .Sh HISTORY These functions first appeared in OpenSSL 1.1.0 and have been available since .Ox 6.3 .