openssl/doc/crypto/BUF_MEM_new.pod
Rich Salz 91da5e7710 Replace all #define's in pod pages.
Function-like macros are replaced with prototypes and a note
that they are implemented as macros.  Constants are just
referenced in-line in the text.

Tweak BIO_TYPE_... documentation.

Also fix RT4592.

Reviewed-by: Matt Caswell <matt@openssl.org>
2016-07-08 12:55:45 -04:00

77 lines
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Text

=pod
=head1 NAME
BUF_MEM_new, BUF_MEM_new_ex, BUF_MEM_free, BUF_MEM_grow
BUF_MEM_grow_clean, BUF_reverse
- simple character array structure
standard C library equivalents
=head1 SYNOPSIS
#include <openssl/buffer.h>
BUF_MEM *BUF_MEM_new(void);
BUF_MEM *BUF_MEM_new_ex(unsigned long flags);
void BUF_MEM_free(BUF_MEM *a);
int BUF_MEM_grow(BUF_MEM *str, int len);
size_t BUF_MEM_grow_clean(BUF_MEM *str, size_t len);
void BUF_reverse(unsigned char *out, const unsigned char *in, size_t size);
=head1 DESCRIPTION
The buffer library handles simple character arrays. Buffers are used for
various purposes in the library, most notably memory BIOs.
BUF_MEM_new() allocates a new buffer of zero size.
BUF_MEM_new_ex() allocates a buffer with the specified flags.
The flag B<BUF_MEM_FLAG_SECURE> specifies that the B<data> pointer
should be allocated on the secure heap; see L<CRYPTO_secure_malloc(3)>.
BUF_MEM_free() frees up an already existing buffer. The data is zeroed
before freeing up in case the buffer contains sensitive data.
BUF_MEM_grow() changes the size of an already existing buffer to
B<len>. Any data already in the buffer is preserved if it increases in
size.
BUF_MEM_grow_clean() is similar to BUF_MEM_grow() but it sets any free'd
or additionally-allocated memory to zero.
BUF_reverse() reverses B<size> bytes at B<in> into B<out>. If B<out>
is NULL, the array is reversed in-place.
=head1 RETURN VALUES
BUF_MEM_new() returns the buffer or NULL on error.
BUF_MEM_free() has no return value.
BUF_MEM_grow() and BUF_MEM_grow_clean() return
zero on error or the new size (i.e., B<len>).
=head1 SEE ALSO
L<bio(3)>,
L<CRYPTO_secure_malloc(3)>.
=head1 HISTORY
BUF_MEM_new_ex() was added in OpenSSL 1.1.0.
=head1 COPYRIGHT
Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the OpenSSL license (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