BUF_MEM_new(3) LibreSSL BUF_MEM_new(3)NAME
BUF_MEM_new, BUF_MEM_free, BUF_MEM_grow, BUF_strdup - simple character
arrays structure
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, size_t len);
char * BUF_strdup(const char *str);
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
{
size_t length; /* current number of bytes */
char *data;
size_t max; /* size of buffer */
} BUF_MEM;
length is the current size of the buffer in bytes, 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 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 system
strdup() function, BUF_strdup() will accept a NULL argument and will
return NULL in that case. Its use in new programes is discouraged.
The memory allocated from BUF_strdup() should be freed up using the
free() function.
RETURN VALUESBUF_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. len).
SEE ALSObio(3)HISTORYBUF_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.
LibreSSL 2015-03-19 BUF_MEM_new(3)
