You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
73 lines
2.0 KiB
73 lines
2.0 KiB
=pod
|
|
|
|
=head1 NAME
|
|
|
|
BUF_MEM_new, BUF_MEM_free, BUF_MEM_grow, BUF_strdup - simple
|
|
character arrays structure
|
|
|
|
=head1 SYNOPSIS
|
|
|
|
#include <openssl/buffer.h>
|
|
|
|
BUF_MEM *BUF_MEM_new(void);
|
|
|
|
void BUF_MEM_free(BUF_MEM *a);
|
|
|
|
int BUF_MEM_grow(BUF_MEM *str, int len);
|
|
|
|
char * BUF_strdup(const char *str);
|
|
|
|
=head1 DESCRIPTION
|
|
|
|
The buffer library handles simple character arrays. Buffers are used for
|
|
various purposes in the library, most notably memory BIOs.
|
|
|
|
The library uses the BUF_MEM structure defined in buffer.h:
|
|
|
|
typedef struct buf_mem_st
|
|
{
|
|
int length; /* current number of bytes */
|
|
char *data;
|
|
int max; /* size of buffer */
|
|
} BUF_MEM;
|
|
|
|
B<length> is the current size of the buffer in bytes, B<max> is the amount of
|
|
memory allocated to the buffer. There are three functions which handle these
|
|
and one "miscellaneous" function.
|
|
|
|
BUF_MEM_new() allocates a new buffer of zero size.
|
|
|
|
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_strdup() copies a null terminated string into a block of allocated
|
|
memory and returns a pointer to the allocated block.
|
|
Unlike the standard C library strdup() this function uses OPENSSL_malloc() and so
|
|
should be used in preference to the standard library strdup() because it can
|
|
be used for memory leak checking or replacing the malloc() function.
|
|
|
|
The memory allocated from BUF_strdup() should be freed up using the OPENSSL_free()
|
|
function.
|
|
|
|
=head1 RETURN VALUES
|
|
|
|
BUF_MEM_new() returns the buffer or NULL on error.
|
|
|
|
BUF_MEM_free() has no return value.
|
|
|
|
BUF_MEM_grow() returns zero on error or the new size (i.e. B<len>).
|
|
|
|
=head1 SEE ALSO
|
|
|
|
L<bio(3)|bio(3)>
|
|
|
|
=head1 HISTORY
|
|
|
|
BUF_MEM_new(), BUF_MEM_free() and BUF_MEM_grow() are available in all
|
|
versions of SSLeay and OpenSSL. BUF_strdup() was added in SSLeay 0.8.
|
|
|
|
=cut
|
|
|