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