| yuezonghe | 824eb0c | 2024-06-27 02:32:26 -0700 | [diff] [blame^] | 1 | =pod |
| 2 | |
| 3 | =head1 NAME |
| 4 | |
| 5 | BIO_new, BIO_up_ref, BIO_free, BIO_vfree, BIO_free_all |
| 6 | - BIO allocation and freeing functions |
| 7 | |
| 8 | =head1 SYNOPSIS |
| 9 | |
| 10 | #include <openssl/bio.h> |
| 11 | |
| 12 | BIO * BIO_new(const BIO_METHOD *type); |
| 13 | int BIO_up_ref(BIO *a); |
| 14 | int BIO_free(BIO *a); |
| 15 | void BIO_vfree(BIO *a); |
| 16 | void BIO_free_all(BIO *a); |
| 17 | |
| 18 | =head1 DESCRIPTION |
| 19 | |
| 20 | The BIO_new() function returns a new BIO using method B<type>. |
| 21 | |
| 22 | BIO_up_ref() increments the reference count associated with the BIO object. |
| 23 | |
| 24 | BIO_free() frees up a single BIO, BIO_vfree() also frees up a single BIO |
| 25 | but it does not return a value. |
| 26 | If B<a> is NULL nothing is done. |
| 27 | Calling BIO_free() may also have some effect |
| 28 | on the underlying I/O structure, for example it may close the file being |
| 29 | referred to under certain circumstances. For more details see the individual |
| 30 | BIO_METHOD descriptions. |
| 31 | |
| 32 | BIO_free_all() frees up an entire BIO chain, it does not halt if an error |
| 33 | occurs freeing up an individual BIO in the chain. |
| 34 | If B<a> is NULL nothing is done. |
| 35 | |
| 36 | =head1 RETURN VALUES |
| 37 | |
| 38 | BIO_new() returns a newly created BIO or NULL if the call fails. |
| 39 | |
| 40 | BIO_up_ref() and BIO_free() return 1 for success and 0 for failure. |
| 41 | |
| 42 | BIO_free_all() and BIO_vfree() do not return values. |
| 43 | |
| 44 | =head1 NOTES |
| 45 | |
| 46 | If BIO_free() is called on a BIO chain it will only free one BIO resulting |
| 47 | in a memory leak. |
| 48 | |
| 49 | Calling BIO_free_all() on a single BIO has the same effect as calling BIO_free() |
| 50 | on it other than the discarded return value. |
| 51 | |
| 52 | =head1 HISTORY |
| 53 | |
| 54 | BIO_set() was removed in OpenSSL 1.1.0 as BIO type is now opaque. |
| 55 | |
| 56 | =head1 EXAMPLES |
| 57 | |
| 58 | Create a memory BIO: |
| 59 | |
| 60 | BIO *mem = BIO_new(BIO_s_mem()); |
| 61 | |
| 62 | =head1 COPYRIGHT |
| 63 | |
| 64 | Copyright 2000-2019 The OpenSSL Project Authors. All Rights Reserved. |
| 65 | |
| 66 | Licensed under the OpenSSL license (the "License"). You may not use |
| 67 | this file except in compliance with the License. You can obtain a copy |
| 68 | in the file LICENSE in the source distribution or at |
| 69 | L<https://www.openssl.org/source/license.html>. |
| 70 | |
| 71 | =cut |