Document "get/set-app-data" macros.

[thirdparty/openssl.git] / doc / man3 / BIO_get_ex_new_index.pod

=pod

=head1 NAME

BIO_get_ex_new_index, BIO_set_ex_data, BIO_get_ex_data,
BIO_set_app_data, BIO_get_app_data,
DH_get_ex_new_index, DH_set_ex_data, DH_get_ex_data,
DSA_get_ex_new_index, DSA_set_ex_data, DSA_get_ex_data,
ECDH_get_ex_new_index, ECDH_set_ex_data, ECDH_get_ex_data,
EC_KEY_get_ex_new_index, EC_KEY_set_ex_data, EC_KEY_get_ex_data,
ENGINE_get_ex_new_index, ENGINE_set_ex_data, ENGINE_get_ex_data,
RAND_DRBG_set_ex_data, RAND_DRBG_get_ex_data, RAND_DRBG_get_ex_new_index,
RSA_get_ex_new_index, RSA_set_ex_data, RSA_get_ex_data,
RSA_set_app_data, RSA_get_app_data,
SSL_get_ex_new_index, SSL_set_ex_data, SSL_get_ex_data,
SSL_set_app_data, SSL_get_app_data,
SSL_CTX_get_ex_new_index, SSL_CTX_set_ex_data, SSL_CTX_get_ex_data,
SSL_CTX_set_app_data, SSL_CTX_get_app_data,
SSL_SESSION_get_ex_new_index, SSL_SESSION_set_ex_data, SSL_SESSION_get_ex_data,
SSL_SESSION_set_app_data, SSL_SESSION_get_app_data,
UI_get_ex_new_index, UI_set_ex_data, UI_get_ex_data,
UI_set_app_data, UI_get_app_data,
X509_STORE_CTX_get_ex_new_index, X509_STORE_CTX_set_ex_data, X509_STORE_CTX_get_ex_data,
X509_STORE_CTX_set_app_data, X509_STORE_CTX_get_app_data,
X509_STORE_get_ex_new_index, X509_STORE_set_ex_data, X509_STORE_get_ex_data,
X509_get_ex_new_index, X509_set_ex_data, X509_get_ex_data
- application-specific data

=head1 SYNOPSIS

=for openssl generic

 #include <openssl/x509.h>

 int TYPE_get_ex_new_index(long argl, void *argp,
                           CRYPTO_EX_new *new_func,
                           CRYPTO_EX_dup *dup_func,
                           CRYPTO_EX_free *free_func);

 int TYPE_set_ex_data(TYPE *d, int idx, void *arg);

 void *TYPE_get_ex_data(TYPE *d, int idx);

 #define TYPE_set_app_data(TYPE *d, void *arg)
 #define TYPE_get_app_data(TYPE *d)

=head1 DESCRIPTION

In the description here, I<TYPE> is used a placeholder
for any of the OpenSSL datatypes listed in
L<CRYPTO_get_ex_new_index(3)>.

These functions handle application-specific data for OpenSSL data
structures.

TYPE_get_new_ex_index() is a macro that calls CRYPTO_get_ex_new_index()
with the correct B<index> value.

TYPE_set_ex_data() is a function that calls CRYPTO_set_ex_data() with
an offset into the opaque exdata part of the TYPE object.

TYPE_get_ex_data() is a function that calls CRYPTO_get_ex_data() with
an offset into the opaque exdata part of the TYPE object.

For compatibility with previous releases, the exdata index of zero is
reserved for "application data." There are two convenience functions for
this.
TYPE_set_app_data() is a macro that invokes TYPE_set_ex_data() with
B<idx> set to zero.
TYPE_get_app_data() is a macro that invokes TYPE_get_ex_data() with
B<idx> set to zero.
Note that these functions are not defined for the B<RAND_DRBG> type because
there are no backward compatibility concerns.

=head1 RETURN VALUES

TYPE_get_new_ex_index() returns a new index on success or -1 on error.

TYPE_set_ex_data() returns 1 on success or 0 on error.

TYPE_get_ex_data() returns the application data or NULL if an error occurred.

=head1 SEE ALSO

L<CRYPTO_get_ex_new_index(3)>.

=head1 COPYRIGHT

Copyright 2015-2018 The OpenSSL Project Authors. All Rights Reserved.

Licensed under the Apache License 2.0 (the "License").  You may not use
this file except in compliance with the License.  You can obtain a copy
in the file LICENSE in the source distribution or at
L<https://www.openssl.org/source/license.html>.

=cut