#ifndef __LIBSSH2_SESSION_H #define __LIBSSH2_SESSION_H /* Copyright (C) Sara Golemon * Copyright (C) Daniel Stenberg * Copyright (C) Simon Josefsson * All rights reserved. * * Redistribution and use in source and binary forms, * with or without modification, are permitted provided * that the following conditions are met: * * Redistributions of source code must retain the above * copyright notice, this list of conditions and the * following disclaimer. * * Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials * provided with the distribution. * * Neither the name of the copyright holder nor the names * of any other contributors may be used to endorse or * promote products derived from this software without * specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY * OF SUCH DAMAGE. * * SPDX-License-Identifier: BSD-3-Clause */ /* Conveniance-macros to allow code like this; int rc = BLOCK_ADJUST(rc, session, session_startup(session, sock)); int rc = BLOCK_ADJUST_ERRNO(ptr, session, session_startup(session, sock)); The point being to make sure that while in non-blocking mode these always return no matter what the return code is, but in blocking mode it blocks if EAGAIN is the reason for the return from the underlying function. */ #define BLOCK_ADJUST(rc, sess, x) \ do { \ time_t entry_time = time(NULL); \ do { \ rc = x; \ /* the order of the check below is important to properly \ deal with the case when the 'sess' is freed */ \ if((rc != LIBSSH2_ERROR_EAGAIN) || !sess->api_block_mode) \ break; \ rc = _libssh2_wait_socket(sess, entry_time); \ } while(!rc); \ } while(0) /* * For functions that returns a pointer, we need to check if the API is * non-blocking and return immediately. If the pointer is non-NULL we return * immediately. If the API is blocking and we get a NULL we check the errno * and *only* if that is EAGAIN we loop and wait for socket action. */ #define BLOCK_ADJUST_ERRNO(ptr, sess, x) \ do { \ time_t entry_time = time(NULL); \ int rc; \ do { \ ptr = x; \ if(!sess->api_block_mode || \ (ptr != NULL) || \ (libssh2_session_last_errno(sess) != LIBSSH2_ERROR_EAGAIN)) \ break; \ rc = _libssh2_wait_socket(sess, entry_time); \ } while(!rc); \ } while(0) int _libssh2_wait_socket(LIBSSH2_SESSION *session, time_t entry_time); /* this is the lib-internal set blocking function */ int _libssh2_session_set_blocking(LIBSSH2_SESSION * session, int blocking); #endif /* __LIBSSH2_SESSION_H */