1 /* $NetBSD: evmap-internal.h,v 1.5 2020/05/25 20:47:33 christos Exp $ */ 2 3 /* 4 * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. The name of the author may not be used to endorse or promote products 15 * derived from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 #ifndef EVMAP_INTERNAL_H_INCLUDED_ 29 #define EVMAP_INTERNAL_H_INCLUDED_ 30 31 /** @file evmap-internal.h 32 * 33 * An event_map is a utility structure to map each fd or signal to zero or 34 * more events. Functions to manipulate event_maps should only be used from 35 * inside libevent. They generally need to hold the lock on the corresponding 36 * event_base. 37 **/ 38 39 struct event_base; 40 struct event; 41 42 /** Initialize an event_map for use. 43 */ 44 void evmap_io_initmap_(struct event_io_map* ctx); 45 void evmap_signal_initmap_(struct event_signal_map* ctx); 46 47 /** Remove all entries from an event_map. 48 49 @param ctx the map to clear. 50 */ 51 void evmap_io_clear_(struct event_io_map* ctx); 52 void evmap_signal_clear_(struct event_signal_map* ctx); 53 54 /** Add an IO event (some combination of EV_READ or EV_WRITE) to an 55 event_base's list of events on a given file descriptor, and tell the 56 underlying eventops about the fd if its state has changed. 57 58 Requires that ev is not already added. 59 60 @param base the event_base to operate on. 61 @param fd the file descriptor corresponding to ev. 62 @param ev the event to add. 63 */ 64 int evmap_io_add_(struct event_base *base, evutil_socket_t fd, struct event *ev); 65 /** Remove an IO event (some combination of EV_READ or EV_WRITE) to an 66 event_base's list of events on a given file descriptor, and tell the 67 underlying eventops about the fd if its state has changed. 68 69 @param base the event_base to operate on. 70 @param fd the file descriptor corresponding to ev. 71 @param ev the event to remove. 72 */ 73 int evmap_io_del_(struct event_base *base, evutil_socket_t fd, struct event *ev); 74 /** Active the set of events waiting on an event_base for a given fd. 75 76 @param base the event_base to operate on. 77 @param fd the file descriptor that has become active. 78 @param events a bitmask of EV_READ|EV_WRITE|EV_ET. 79 */ 80 void evmap_io_active_(struct event_base *base, evutil_socket_t fd, short events); 81 82 83 /* These functions behave in the same way as evmap_io_*, except they work on 84 * signals rather than fds. signals use a linear map everywhere; fds use 85 * either a linear map or a hashtable. */ 86 int evmap_signal_add_(struct event_base *base, int signum, struct event *ev); 87 int evmap_signal_del_(struct event_base *base, int signum, struct event *ev); 88 void evmap_signal_active_(struct event_base *base, evutil_socket_t signum, int ncalls); 89 90 /* Return the fdinfo object associated with a given fd. If the fd has no 91 * events associated with it, the result may be NULL. 92 */ 93 void *evmap_io_get_fdinfo_(struct event_io_map *ctx, evutil_socket_t fd); 94 95 /* Helper for event_reinit(): Tell the backend to re-add every fd and signal 96 * for which we have a pending event. 97 */ 98 int evmap_reinit_(struct event_base *base); 99 100 /* Helper for event_base_free(): Call event_del() on every pending fd and 101 * signal event. 102 */ 103 void evmap_delete_all_(struct event_base *base); 104 105 /* Helper for event_base_assert_ok_(): Check referential integrity of the 106 * evmaps. 107 */ 108 void evmap_check_integrity_(struct event_base *base); 109 110 /* Helper: Call fn on every fd or signal event, passing as its arguments the 111 * provided event_base, the event, and arg. If fn returns 0, process the next 112 * event. If it returns any other value, return that value and process no 113 * more events. 114 */ 115 int evmap_foreach_event_(struct event_base *base, 116 event_base_foreach_event_cb fn, 117 void *arg); 118 119 #endif /* EVMAP_INTERNAL_H_INCLUDED_ */ 120