| =pod |
| |
| =head1 NAME |
| |
| BN_zero, BN_one, BN_value_one, BN_set_word, BN_get_word - BIGNUM assignment |
| operations |
| |
| =head1 SYNOPSIS |
| |
| #include <openssl/bn.h> |
| |
| void BN_zero(BIGNUM *a); |
| int BN_one(BIGNUM *a); |
| |
| const BIGNUM *BN_value_one(void); |
| |
| int BN_set_word(BIGNUM *a, BN_ULONG w); |
| unsigned BN_ULONG BN_get_word(BIGNUM *a); |
| |
| =head1 DESCRIPTION |
| |
| B<BN_ULONG> is a macro that will be an unsigned integral type optimized |
| for the most efficient implementation on the local platform. |
| |
| BN_zero(), BN_one() and BN_set_word() set B<a> to the values 0, 1 and |
| B<w> respectively. BN_zero() and BN_one() are macros. |
| |
| BN_value_one() returns a B<BIGNUM> constant of value 1. This constant |
| is useful for use in comparisons and assignment. |
| |
| BN_get_word() returns B<a>, if it can be represented as a B<BN_ULONG>. |
| |
| =head1 RETURN VALUES |
| |
| BN_get_word() returns the value B<a>, or all-bits-set if B<a> cannot |
| be represented as a single integer. |
| |
| BN_one() and BN_set_word() return 1 on success, 0 otherwise. |
| BN_value_one() returns the constant. |
| BN_zero() never fails and returns no value. |
| |
| =head1 BUGS |
| |
| If a B<BIGNUM> is equal to the value of all-bits-set, it will collide |
| with the error condition returned by BN_get_word() which uses that |
| as an error value. |
| |
| B<BN_ULONG> should probably be a typedef. |
| |
| =head1 SEE ALSO |
| |
| L<BN_bn2bin(3)> |
| |
| =head1 HISTORY |
| |
| In OpenSSL 0.9.8, BN_zero() was changed to not return a value; previous |
| versions returned an int. |
| |
| =head1 COPYRIGHT |
| |
| Copyright 2000-2018 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 |
