| =pod |
| |
| =head1 NAME |
| |
| BIO_socket_wait, |
| BIO_wait, |
| BIO_do_connect_retry |
| - BIO connection utility functions |
| |
| =head1 SYNOPSIS |
| |
| #include <openssl/bio.h> |
| |
| #ifndef OPENSSL_NO_SOCK |
| int BIO_socket_wait(int fd, int for_read, time_t max_time); |
| #endif |
| int BIO_wait(BIO *bio, time_t max_time, unsigned int nap_milliseconds); |
| int BIO_do_connect_retry(BIO *bio, int timeout, int nap_milliseconds); |
| |
| =head1 DESCRIPTION |
| |
| BIO_socket_wait() waits on the socket B<fd> for reading if B<for_read> is not 0, |
| else for writing, at most until B<max_time>. |
| It succeeds immediately if B<max_time> == 0 (which means no timeout given). |
| |
| BIO_wait() waits at most until B<max_time> on the given (typically socket-based) |
| B<bio>, for reading if B<bio> is supposed to read, else for writing. |
| It is used by BIO_do_connect_retry() and can be used together L<BIO_read(3)>. |
| It succeeds immediately if B<max_time> == 0 (which means no timeout given). |
| If sockets are not available it supports polling by succeeding after sleeping |
| at most the given B<nap_milliseconds> in order to avoid a tight busy loop. |
| Via B<nap_milliseconds> the caller determines the polling granularity. |
| |
| BIO_do_connect_retry() connects via the given B<bio>. |
| It retries BIO_do_connect() as far as needed to reach a definite outcome, |
| i.e., connection succeeded, timeout has been reached, or an error occurred. |
| For nonblocking and potentially even non-socket BIOs it polls |
| every B<nap_milliseconds> and sleeps in between using BIO_wait(). |
| If B<nap_milliseconds> is < 0 then a default value of 100 ms is used. |
| If the B<timeout> parameter is > 0 this indicates the maximum number of seconds |
| to wait until the connection is established or a definite error occurred. |
| A value of 0 enables waiting indefinitely (i.e, no timeout), |
| while a value < 0 means that BIO_do_connect() is tried only once. |
| The function may, directly or indirectly, invoke ERR_clear_error(). |
| |
| =head1 RETURN VALUES |
| |
| BIO_socket_wait(), BIO_wait(), and BIO_do_connect_retry() |
| return -1 on error, 0 on timeout, and 1 on success. |
| |
| =head1 SEE ALSO |
| |
| L<BIO_do_connect(3)>, L<BIO_read(3)> |
| |
| =head1 HISTORY |
| |
| BIO_socket_wait(), BIO_wait(), and BIO_do_connect_retry() |
| were added in OpenSSL 3.0. |
| |
| =head1 COPYRIGHT |
| |
| Copyright 2019-2020 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 |
| L<https://www.openssl.org/source/license.html>. |
| |
| =cut |
