NAME

       SSL_free_buffers, SSL_alloc_buffers - manage SSL structure buffers

SYNOPSIS

        #include <openssl/ssl.h>

        int SSL_free_buffers(SSL *ssl);
        int SSL_alloc_buffers(SSL *ssl);

DESCRIPTION

       SSL_free_buffers() frees the read and write buffers of the given ssl.  SSL_alloc_buffers()
       allocates the read and write buffers of the given ssl.

       The SSL_MODE_RELEASE_BUFFERS mode releases read or write buffers whenever the buffers have
       been drained. These functions allow applications to manually control when buffers are
       freed and allocated.

       After freeing the buffers, the buffers are automatically reallocated upon a new read or
       write. The SSL_alloc_buffers() does not need to be called, but can be used to make sure
       the buffers are preallocated. This can be used to avoid allocation during data processing
       or with CRYPTO_set_mem_functions() to control where and how buffers are allocated.

RETURN VALUES

       The following return values can occur:

       0 (Failure)
           The SSL_free_buffers() function returns 0 when there is pending data to be read or
           written. The SSL_alloc_buffers() function returns 0 when there is an allocation
           failure.

       1 (Success)
           The SSL_free_buffers() function returns 1 if the buffers have been freed. This value
           is also returned if the buffers had been freed before calling SSL_free_buffers().  The
           SSL_alloc_buffers() function returns 1 if the buffers have been allocated.  This value
           is also returned if the buffers had been allocated before calling SSL_alloc_buffers().

SEE ALSO

       ssl(7), SSL_free(3), SSL_clear(3), SSL_new(3), SSL_CTX_set_mode(3),
       CRYPTO_set_mem_functions(3)

COPYRIGHT

       Copyright 2017-2020 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 <https://www.openssl.org/source/license.html>.