1 /* $NetBSD: listener.h,v 1.1.1.1 2013/04/11 16:43:34 christos Exp $ */ 2 /* 3 * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu> 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 _EVENT2_LISTENER_H_ 29 #define _EVENT2_LISTENER_H_ 30 31 #ifdef __cplusplus 32 extern "C" { 33 #endif 34 35 #include <event2/event.h> 36 37 struct sockaddr; 38 struct evconnlistener; 39 40 /** 41 A callback that we invoke when a listener has a new connection. 42 43 @param listener The evconnlistener 44 @param fd The new file descriptor 45 @param addr The source address of the connection 46 @param socklen The length of addr 47 @param user_arg the pointer passed to evconnlistener_new() 48 */ 49 typedef void (*evconnlistener_cb)(struct evconnlistener *, evutil_socket_t, struct sockaddr *, int socklen, void *); 50 51 /** 52 A callback that we invoke when a listener encounters a non-retriable error. 53 54 @param listener The evconnlistener 55 @param user_arg the pointer passed to evconnlistener_new() 56 */ 57 typedef void (*evconnlistener_errorcb)(struct evconnlistener *, void *); 58 59 /** Flag: Indicates that we should not make incoming sockets nonblocking 60 * before passing them to the callback. */ 61 #define LEV_OPT_LEAVE_SOCKETS_BLOCKING (1u<<0) 62 /** Flag: Indicates that freeing the listener should close the underlying 63 * socket. */ 64 #define LEV_OPT_CLOSE_ON_FREE (1u<<1) 65 /** Flag: Indicates that we should set the close-on-exec flag, if possible */ 66 #define LEV_OPT_CLOSE_ON_EXEC (1u<<2) 67 /** Flag: Indicates that we should disable the timeout (if any) between when 68 * this socket is closed and when we can listen again on the same port. */ 69 #define LEV_OPT_REUSEABLE (1u<<3) 70 /** Flag: Indicates that the listener should be locked so it's safe to use 71 * from multiple threadcs at once. */ 72 #define LEV_OPT_THREADSAFE (1u<<4) 73 74 /** 75 Allocate a new evconnlistener object to listen for incoming TCP connections 76 on a given file descriptor. 77 78 @param base The event base to associate the listener with. 79 @param cb A callback to be invoked when a new connection arrives. If the 80 callback is NULL, the listener will be treated as disabled until the 81 callback is set. 82 @param ptr A user-supplied pointer to give to the callback. 83 @param flags Any number of LEV_OPT_* flags 84 @param backlog Passed to the listen() call to determine the length of the 85 acceptable connection backlog. Set to -1 for a reasonable default. 86 Set to 0 if the socket is already listening. 87 @param fd The file descriptor to listen on. It must be a nonblocking 88 file descriptor, and it should already be bound to an appropriate 89 port and address. 90 */ 91 struct evconnlistener *evconnlistener_new(struct event_base *base, 92 evconnlistener_cb cb, void *ptr, unsigned flags, int backlog, 93 evutil_socket_t fd); 94 /** 95 Allocate a new evconnlistener object to listen for incoming TCP connections 96 on a given address. 97 98 @param base The event base to associate the listener with. 99 @param cb A callback to be invoked when a new connection arrives. If the 100 callback is NULL, the listener will be treated as disabled until the 101 callback is set. 102 @param ptr A user-supplied pointer to give to the callback. 103 @param flags Any number of LEV_OPT_* flags 104 @param backlog Passed to the listen() call to determine the length of the 105 acceptable connection backlog. Set to -1 for a reasonable default. 106 @param addr The address to listen for connections on. 107 @param socklen The length of the address. 108 */ 109 struct evconnlistener *evconnlistener_new_bind(struct event_base *base, 110 evconnlistener_cb cb, void *ptr, unsigned flags, int backlog, 111 const struct sockaddr *sa, int socklen); 112 /** 113 Disable and deallocate an evconnlistener. 114 */ 115 void evconnlistener_free(struct evconnlistener *lev); 116 /** 117 Re-enable an evconnlistener that has been disabled. 118 */ 119 int evconnlistener_enable(struct evconnlistener *lev); 120 /** 121 Stop listening for connections on an evconnlistener. 122 */ 123 int evconnlistener_disable(struct evconnlistener *lev); 124 125 /** Return an evconnlistener's associated event_base. */ 126 struct event_base *evconnlistener_get_base(struct evconnlistener *lev); 127 128 /** Return the socket that an evconnlistner is listening on. */ 129 evutil_socket_t evconnlistener_get_fd(struct evconnlistener *lev); 130 131 /** Change the callback on the listener to cb and its user_data to arg. 132 */ 133 void evconnlistener_set_cb(struct evconnlistener *lev, 134 evconnlistener_cb cb, void *arg); 135 136 /** Set an evconnlistener's error callback. */ 137 void evconnlistener_set_error_cb(struct evconnlistener *lev, 138 evconnlistener_errorcb errorcb); 139 140 #ifdef __cplusplus 141 } 142 #endif 143 144 #endif 145