| =pod |
| |
| =head1 NAME |
| |
| SSL_want, SSL_want_nothing, SSL_want_read, SSL_want_write, SSL_want_x509_lookup - obtain state information TLS/SSL I/O operation |
| |
| =head1 SYNOPSIS |
| |
| #include <openssl/ssl.h> |
| |
| int SSL_want(SSL *ssl); |
| int SSL_want_nothing(SSL *ssl); |
| int SSL_want_read(SSL *ssl); |
| int SSL_want_write(SSL *ssl); |
| int SSL_want_x509_lookup(SSL *ssl); |
| |
| =head1 DESCRIPTION |
| |
| SSL_want() returns state information for the SSL object B<ssl>. |
| |
| The other SSL_want_*() calls are shortcuts for the possible states returned |
| by SSL_want(). |
| |
| =head1 NOTES |
| |
| SSL_want() examines the internal state information of the SSL object. Its |
| return values are similar to that of L<SSL_get_error(3)|SSL_get_error(3)>. |
| Unlike L<SSL_get_error(3)|SSL_get_error(3)>, which also evaluates the |
| error queue, the results are obtained by examining an internal state flag |
| only. The information must therefore only be used for normal operation under |
| non-blocking I/O. Error conditions are not handled and must be treated |
| using L<SSL_get_error(3)|SSL_get_error(3)>. |
| |
| The result returned by SSL_want() should always be consistent with |
| the result of L<SSL_get_error(3)|SSL_get_error(3)>. |
| |
| =head1 RETURN VALUES |
| |
| The following return values can currently occur for SSL_want(): |
| |
| =over 4 |
| |
| =item SSL_NOTHING |
| |
| There is no data to be written or to be read. |
| |
| =item SSL_WRITING |
| |
| There are data in the SSL buffer that must be written to the underlying |
| B<BIO> layer in order to complete the actual SSL_*() operation. |
| A call to L<SSL_get_error(3)|SSL_get_error(3)> should return |
| SSL_ERROR_WANT_WRITE. |
| |
| =item SSL_READING |
| |
| More data must be read from the underlying B<BIO> layer in order to |
| complete the actual SSL_*() operation. |
| A call to L<SSL_get_error(3)|SSL_get_error(3)> should return |
| SSL_ERROR_WANT_READ. |
| |
| =item SSL_X509_LOOKUP |
| |
| The operation did not complete because an application callback set by |
| SSL_CTX_set_client_cert_cb() has asked to be called again. |
| A call to L<SSL_get_error(3)|SSL_get_error(3)> should return |
| SSL_ERROR_WANT_X509_LOOKUP. |
| |
| =back |
| |
| SSL_want_nothing(), SSL_want_read(), SSL_want_write(), SSL_want_x509_lookup() |
| return 1, when the corresponding condition is true or 0 otherwise. |
| |
| =head1 SEE ALSO |
| |
| L<ssl(3)|ssl(3)>, L<err(3)|err(3)>, L<SSL_get_error(3)|SSL_get_error(3)> |
| |
| =cut |
