1 /* 2 * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu> 3 * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 #ifndef _EVENT2_LISTENER_H_ 28 #define _EVENT2_LISTENER_H_ 29 30 #ifdef __cplusplus 31 extern "C" { 32 #endif 33 34 #include <event2/event.h> 35 36 struct sockaddr; 37 struct evconnlistener; 38 39 /** 40 A callback that we invoke when a listener has a new connection. 41 42 @param listener The evconnlistener 43 @param fd The new file descriptor 44 @param addr The source address of the connection 45 @param socklen The length of addr 46 @param user_arg the pointer passed to evconnlistener_new() 47 */ 48 typedef void (*evconnlistener_cb)(struct evconnlistener *, evutil_socket_t, struct sockaddr *, int socklen, void *); 49 50 /** 51 A callback that we invoke when a listener encounters a non-retriable error. 52 53 @param listener The evconnlistener 54 @param user_arg the pointer passed to evconnlistener_new() 55 */ 56 typedef void (*evconnlistener_errorcb)(struct evconnlistener *, void *); 57 58 /** Flag: Indicates that we should not make incoming sockets nonblocking 59 * before passing them to the callback. */ 60 #define LEV_OPT_LEAVE_SOCKETS_BLOCKING (1u<<0) 61 /** Flag: Indicates that freeing the listener should close the underlying 62 * socket. */ 63 #define LEV_OPT_CLOSE_ON_FREE (1u<<1) 64 /** Flag: Indicates that we should set the close-on-exec flag, if possible */ 65 #define LEV_OPT_CLOSE_ON_EXEC (1u<<2) 66 /** Flag: Indicates that we should disable the timeout (if any) between when 67 * this socket is closed and when we can listen again on the same port. */ 68 #define LEV_OPT_REUSEABLE (1u<<3) 69 /** Flag: Indicates that the listener should be locked so it's safe to use 70 * from multiple threadcs at once. */ 71 #define LEV_OPT_THREADSAFE (1u<<4) 72 73 /** 74 Allocate a new evconnlistener object to listen for incoming TCP connections 75 on a given file descriptor. 76 77 @param base The event base to associate the listener with. 78 @param cb A callback to be invoked when a new connection arrives. If the 79 callback is NULL, the listener will be treated as disabled until the 80 callback is set. 81 @param ptr A user-supplied pointer to give to the callback. 82 @param flags Any number of LEV_OPT_* flags 83 @param backlog Passed to the listen() call to determine the length of the 84 acceptable connection backlog. Set to -1 for a reasonable default. 85 Set to 0 if the socket is already listening. 86 @param fd The file descriptor to listen on. It must be a nonblocking 87 file descriptor, and it should already be bound to an appropriate 88 port and address. 89 */ 90 struct evconnlistener *evconnlistener_new(struct event_base *base, 91 evconnlistener_cb cb, void *ptr, unsigned flags, int backlog, 92 evutil_socket_t fd); 93 /** 94 Allocate a new evconnlistener object to listen for incoming TCP connections 95 on a given address. 96 97 @param base The event base to associate the listener with. 98 @param cb A callback to be invoked when a new connection arrives. If the 99 callback is NULL, the listener will be treated as disabled until the 100 callback is set. 101 @param ptr A user-supplied pointer to give to the callback. 102 @param flags Any number of LEV_OPT_* flags 103 @param backlog Passed to the listen() call to determine the length of the 104 acceptable connection backlog. Set to -1 for a reasonable default. 105 @param addr The address to listen for connections on. 106 @param socklen The length of the address. 107 */ 108 struct evconnlistener *evconnlistener_new_bind(struct event_base *base, 109 evconnlistener_cb cb, void *ptr, unsigned flags, int backlog, 110 const struct sockaddr *sa, int socklen); 111 /** 112 Disable and deallocate an evconnlistener. 113 */ 114 void evconnlistener_free(struct evconnlistener *lev); 115 /** 116 Re-enable an evconnlistener that has been disabled. 117 */ 118 int evconnlistener_enable(struct evconnlistener *lev); 119 /** 120 Stop listening for connections on an evconnlistener. 121 */ 122 int evconnlistener_disable(struct evconnlistener *lev); 123 124 /** Return an evconnlistener's associated event_base. */ 125 struct event_base *evconnlistener_get_base(struct evconnlistener *lev); 126 127 /** Return the socket that an evconnlistner is listening on. */ 128 evutil_socket_t evconnlistener_get_fd(struct evconnlistener *lev); 129 130 /** Change the callback on the listener to cb and its user_data to arg. 131 */ 132 void evconnlistener_set_cb(struct evconnlistener *lev, 133 evconnlistener_cb cb, void *arg); 134 135 /** Set an evconnlistener's error callback. */ 136 void evconnlistener_set_error_cb(struct evconnlistener *lev, 137 evconnlistener_errorcb errorcb); 138 139 #ifdef __cplusplus 140 } 141 #endif 142 143 #endif 144