| /* Network-related functions for internal library use. |
| Copyright (C) 2016-2018 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #ifndef _NET_INTERNAL_H |
| #define _NET_INTERNAL_H 1 |
| |
| #include <arpa/inet.h> |
| #include <stdbool.h> |
| #include <stdint.h> |
| #include <sys/time.h> |
| |
| int __inet6_scopeid_pton (const struct in6_addr *address, |
| const char *scope, uint32_t *result); |
| libc_hidden_proto (__inet6_scopeid_pton) |
| |
| |
| /* Deadline handling for enforcing timeouts. |
| |
| Code should call __deadline_current_time to obtain the current time |
| and cache it locally. The cache needs updating after every |
| long-running or potentially blocking operation. Deadlines relative |
| to the current time can be computed using __deadline_from_timeval. |
| The deadlines may have to be recomputed in response to certain |
| events (such as an incoming packet), but they are absolute (not |
| relative to the current time). A timeout suitable for use with the |
| poll function can be computed from such a deadline using |
| __deadline_to_ms. |
| |
| The fields in the structs defined belowed should only be used |
| within the implementation. */ |
| |
| /* Cache of the current time. Used to compute deadlines from relative |
| timeouts and vice versa. */ |
| struct deadline_current_time |
| { |
| struct timespec current; |
| }; |
| |
| /* Return the current time. Terminates the process if the current |
| time is not available. */ |
| struct deadline_current_time __deadline_current_time (void) attribute_hidden; |
| |
| /* Computed absolute deadline. */ |
| struct deadline |
| { |
| struct timespec absolute; |
| }; |
| |
| |
| /* For internal use only. */ |
| static inline bool |
| __deadline_is_infinite (struct deadline deadline) |
| { |
| return deadline.absolute.tv_nsec < 0; |
| } |
| |
| /* Return true if the current time is at the deadline or past it. */ |
| static inline bool |
| __deadline_elapsed (struct deadline_current_time current, |
| struct deadline deadline) |
| { |
| return !__deadline_is_infinite (deadline) |
| && (current.current.tv_sec > deadline.absolute.tv_sec |
| || (current.current.tv_sec == deadline.absolute.tv_sec |
| && current.current.tv_nsec >= deadline.absolute.tv_nsec)); |
| } |
| |
| /* Return the deadline which occurs first. */ |
| static inline struct deadline |
| __deadline_first (struct deadline left, struct deadline right) |
| { |
| if (__deadline_is_infinite (right) |
| || left.absolute.tv_sec < right.absolute.tv_sec |
| || (left.absolute.tv_sec == right.absolute.tv_sec |
| && left.absolute.tv_nsec < right.absolute.tv_nsec)) |
| return left; |
| else |
| return right; |
| } |
| |
| /* Add TV to the current time and return it. Returns a special |
| infinite absolute deadline on overflow. */ |
| struct deadline __deadline_from_timeval (struct deadline_current_time, |
| struct timeval tv) attribute_hidden; |
| |
| /* Compute the number of milliseconds until the specified deadline, |
| from the current time in the argument. The result is mainly for |
| use with poll. If the deadline has already passed, return 0. If |
| the result would overflow an int, return INT_MAX. */ |
| int __deadline_to_ms (struct deadline_current_time, struct deadline) |
| attribute_hidden; |
| |
| /* Return true if TV.tv_sec is non-negative and TV.tv_usec is in the |
| interval [0, 999999]. */ |
| static inline bool |
| __is_timeval_valid_timeout (struct timeval tv) |
| { |
| return tv.tv_sec >= 0 && tv.tv_usec >= 0 && tv.tv_usec < 1000 * 1000; |
| } |
| |
| #endif /* _NET_INTERNAL_H */ |