Edit: /usr/include/proftpd/event.h (3583B)
/*
* ProFTPD - FTP server daemon
* Copyright (c) 2003-2016 The ProFTPD Project team
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA.
*
* As a special exemption, The ProFTPD Project team and other respective
* copyright holders give permission to link this program with OpenSSL, and
* distribute the resulting executable, without including the source code for
* OpenSSL in the source distribution.
*/
/* Event management */
#ifndef PR_EVENT_H
#define PR_EVENT_H
/* Register a handler for the given event. The registered handler
* callback function takes two arguments: a pointer to some event-specific
* data and a pointer to some user-defined data. This user-defined data
* is set as the last argument in this registration function, and may be
* NULL.
*
* The return value is zero if the registration succeeded, and -1 if
* there was an error (in which case, errno will be set appropriately).
*
* Note that the registered event name is assumed to be a string constant;
* the Event API stores a pointer to the given string, not a duplicate
* of it.
*/
int pr_event_register(module *m, const char *event,
void (*cb)(const void *, void *), void *user_data);
/* Remove the given event handler from the event registration lists. The
* return value is zero if successful, and -1 if there was an error (in
* which case, errno will be set appropriately).
*
* If the module pointer is non-NULL, the event handler being unregistered
* must have been registered by that module. If the event name is
* non-NULL, then only the handler for that specific event is unregistered;
* otherwise, all events for the given module will be unregistered. If the
* callback pointer is non-NULL, the event handler being unregistered must be
* that specific handler.
*
* This arrangement means that it is possible, though considered terribly
* impolite, for the caller to unregister all handlers for a given event,
* regardless of registree, using:
*
* pr_event_unregister(NULL, event_name, NULL);
*
* Although rare, there are cases where this kind of blanket unregistration
* is necessary. More common will be the case where a module needs to
* unregister all of its event listeners at once:
*
* pr_event_unregister(&my_module, NULL, NULL);
*/
int pr_event_unregister(module *m, const char *event,
void (*cb)(const void *, void *));
/* Generate an event. The named event is dispatched to any handlers that
* have registered an interest in handling this event. Any event-specific
* data is sent to the registered handlers.
*/
void pr_event_generate(const char *event, const void *event_data);
/* Returns the number of registered listeners for the given event,
* or -1 (with errno set appropriately) if there was an error.
*/
int pr_event_listening(const char *event);
/* Dump Events information. */
void pr_event_dump(void (*)(const char *, ...));
#endif /* PR_EVENT_H */