| =pod |
| |
| =head1 NAME |
| |
| SSL_waiting_for_async, |
| SSL_get_all_async_fds, |
| SSL_get_changed_async_fds |
| - manage asynchronous operations |
| |
| =head1 SYNOPSIS |
| |
| =for comment multiple includes |
| |
| #include <openssl/async.h> |
| #include <openssl/ssl.h> |
| |
| int SSL_waiting_for_async(SSL *s); |
| int SSL_get_all_async_fds(SSL *s, OSSL_ASYNC_FD *fd, size_t *numfds); |
| int SSL_get_changed_async_fds(SSL *s, OSSL_ASYNC_FD *addfd, size_t *numaddfds, |
| OSSL_ASYNC_FD *delfd, size_t *numdelfds); |
| |
| =head1 DESCRIPTION |
| |
| SSL_waiting_for_async() determines whether an SSL connection is currently |
| waiting for asynchronous operations to complete (see the SSL_MODE_ASYNC mode in |
| L<SSL_CTX_set_mode(3)>). |
| |
| SSL_get_all_async_fds() returns a list of file descriptor which can be used in a |
| call to select() or poll() to determine whether the current asynchronous |
| operation has completed or not. A completed operation will result in data |
| appearing as "read ready" on the file descriptor (no actual data should be read |
| from the file descriptor). This function should only be called if the SSL object |
| is currently waiting for asynchronous work to complete (i.e. |
| SSL_ERROR_WANT_ASYNC has been received - see L<SSL_get_error(3)>). Typically the |
| list will only contain one file descriptor. However if multiple asynchronous |
| capable engines are in use then more than one is possible. The number of file |
| descriptors returned is stored in B<*numfds> and the file descriptors themselves |
| are in B<*fds>. The B<fds> parameter may be NULL in which case no file |
| descriptors are returned but B<*numfds> is still populated. It is the callers |
| responsibility to ensure sufficient memory is allocated at B<*fds> so typically |
| this function is called twice (once with a NULL B<fds> parameter and once |
| without). |
| |
| SSL_get_changed_async_fds() returns a list of the asynchronous file descriptors |
| that have been added and a list that have been deleted since the last |
| SSL_ERROR_WANT_ASYNC was received (or since the SSL object was created if no |
| SSL_ERROR_WANT_ASYNC has been received). Similar to SSL_get_all_async_fds() it |
| is the callers responsibility to ensure that B<*addfd> and B<*delfd> have |
| sufficient memory allocated, although they may be NULL. The number of added fds |
| and the number of deleted fds are stored in B<*numaddfds> and B<*numdelfds> |
| respectively. |
| |
| =head1 RETURN VALUES |
| |
| SSL_waiting_for_async() will return 1 if the current SSL operation is waiting |
| for an async operation to complete and 0 otherwise. |
| |
| SSL_get_all_async_fds() and SSL_get_changed_async_fds() return 1 on success or |
| 0 on error. |
| |
| =head1 NOTES |
| |
| On Windows platforms the openssl/async.h header is dependent on some |
| of the types customarily made available by including windows.h. The |
| application developer is likely to require control over when the latter |
| is included, commonly as one of the first included headers. Therefore |
| it is defined as an application developer's responsibility to include |
| windows.h prior to async.h. |
| |
| =head1 SEE ALSO |
| |
| L<SSL_get_error(3)>, L<SSL_CTX_set_mode(3)> |
| |
| =head1 HISTORY |
| |
| SSL_waiting_for_async(), SSL_get_all_async_fds() and SSL_get_changed_async_fds() |
| were first added to OpenSSL 1.1.0. |
| |
| =head1 COPYRIGHT |
| |
| Copyright 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 |