libio/misc/event.c

/*
 *  ircd-hybrid: an advanced Internet Relay Chat Daemon(ircd).
 *  event.c: Event functions.
 *
 *  Copyright (C) 1998-2000 Regents of the University of California
 *  Copyright (C) 2001-2002 Hybrid Development Team
 *
 *  Code borrowed from the squid web cache by Adrian Chadd.
 *  Original header:
 *
 *  DEBUG: section 41   Event Processing
 *  AUTHOR: Henrik Nordstrom
 *
 *  SQUID Internet Object Cache  http://squid.nlanr.net/Squid/
 *  ----------------------------------------------------------
 *
 *  Squid is the result of efforts by numerous individuals from the
 *  Internet community.  Development is led by Duane Wessels of the
 *  National Laboratory for Applied Network Research and funded by the
 *  National Science Foundation.  Squid is Copyrighted (C) 1998 by
 *  the Regents of the University of California.  Please see the
 *  COPYRIGHT file for full details.  Squid incorporates software
 *  developed and/or copyrighted by other sources.  Please see the
 *  CREDITS file for full details.
 *
 *  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., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 *  USA
 *
 *  $Id: event.c 33 2005-10-02 20:50:00Z knight $
 */

/*
 * How it's used:
 *
 * Should be pretty self-explanatory. Events are added to the static
 * array event_table with a frequency time telling eventRun how often
 * to execute it.
 */

#include "stdinc.h"

const char *last_event_ran = NULL;
struct ev_entry event_table[MAX_EVENTS];

static time_t event_time_min = -1;
static int eventFind(EVH *func, void *arg);

/*
 * void eventAdd(const char *name, EVH *func, void *arg, time_t when)
 *
 * Input: Name of event, function to call, arguments to pass, and frequency
 *        of the event.
 * Output: None
 * Side Effects: Adds the event to the event list.
 */
void
eventAdd(const char *name, EVH *func, void *arg, time_t when)
{
  int i;
  
  /* find first inactive index, or use next index */
  for (i = 0; i < MAX_EVENTS; i++)
  {
    if (event_table[i].active == 0)
    {
      event_table[i].func = func;
      event_table[i].name = name;
      event_table[i].arg = arg;
      event_table[i].when = CurrentTime + when;
      event_table[i].frequency = when; 
      event_table[i].active = 1;

      if ((event_table[i].when < event_time_min) || (event_time_min == -1))
        event_time_min = event_table[i].when;

      return;
    }
  }
  /* XXX if reach here, its an error */
  ilog(L_ERROR, "Event table is full! (%d)", i);
}

/*
 * void eventDelete(EVH *func, void *arg)
 *
 * Input: Function handler, argument that was passed.
 * Output: None
 * Side Effects: Removes the event from the event list
 */
void
eventDelete(EVH *func, void *arg)
{
  int i = eventFind(func, arg);

  if (i == -1)
    return;

  event_table[i].name = NULL;
  event_table[i].func = NULL;
  event_table[i].arg = NULL;
  event_table[i].active = 0;
}

/* 
 * void eventAddIsh(const char *name, EVH *func, void *arg, time_t delta_isa)
 *
 * Input: Name of event, function to call, arguments to pass, and frequency
 *        of the event.
 * Output: None
 * Side Effects: Adds the event to the event list within +- 1/3 of the
 *               specified frequency.
 */
void
eventAddIsh(const char *name, EVH *func, void *arg, time_t delta_ish)
{
  if (delta_ish >= 3.0)
  {
    const time_t two_third = (2 * delta_ish) / 3;
    delta_ish = two_third + ((rand() % 1000) * two_third) / 1000;
      /*
       * XXX I hate the above magic, I don't even know if its right.
       * Grr. -- adrian
       */
  }

  eventAdd(name, func, arg, delta_ish);
}

/*
 * void eventRun(void)
 *
 * Input: None
 * Output: None
 * Side Effects: Runs pending events in the event list
 */
void
eventRun(void)
{
  int i;

  for (i = 0; i < MAX_EVENTS; i++)
  {
    if (event_table[i].active && (event_table[i].when <= CurrentTime))
    {
      last_event_ran = event_table[i].name;
      event_table[i].func(event_table[i].arg);
      event_table[i].when = CurrentTime + event_table[i].frequency;
      event_time_min = -1;
    }
  }
}

/*
 * time_t eventNextTime(void)
 * 
 * Input: None
 * Output: Specifies the next time eventRun() should be run
 * Side Effects: None
 */
time_t
eventNextTime(void)
{
  int i;

  if (event_time_min == -1)
  {
    for (i = 0; i < MAX_EVENTS; i++)
    {
      if (event_table[i].active && ((event_table[i].when < event_time_min) || (event_time_min == -1)))
        event_time_min = event_table[i].when;
    }
  }

  return event_time_min;
}

/*
 * void eventInit(void)
 *
 * Input: None
 * Output: None
 * Side Effects: Initializes the event system. 
 */
void
eventInit(void)
{
  last_event_ran = NULL;
  memset(event_table, 0, sizeof(event_table));
}

/*
 * int eventFind(EVH *func, void *arg)
 *
 * Input: Event function and the argument passed to it
 * Output: Index to the slow in the event_table
 * Side Effects: None
 */
static int
eventFind(EVH *func, void *arg)
{
  int i;

  for (i = 0; i < MAX_EVENTS; i++)
  {
    if ((event_table[i].func == func) &&
        (event_table[i].arg == arg) &&
         event_table[i].active)
      return i;
  }

  return -1;
}

/*
 * void set_back_events(time_t by)
 * Input: Time to set back events by.
 * Output: None.
 * Side-effects: Sets back all events by "by" seconds.
 */
void
set_back_events(time_t by)
{
  int i;

  for (i = 0; i < MAX_EVENTS; i++)
  {
    if (event_table[i].when > by)
      event_table[i].when -= by;
    else
      event_table[i].when = 0;
  }
}
Revision:	69
Committed:	Tue Oct 4 16:09:51 2005 UTC (20 years, 10 months ago) by adx
Content type:	text/x-csrc
File size:	6045 byte(s)
Log Message:	- splitted ircd/libio, all headers connected with libio sources have been moved for internal use only. To use libio interface, include "libio.h" (which is already done in "stdinc.h")
#	User	Rev	Content
1	adx	61	/*
2			* ircd-hybrid: an advanced Internet Relay Chat Daemon(ircd).
3			* event.c: Event functions.
4			*
5			* Copyright (C) 1998-2000 Regents of the University of California
6			* Copyright (C) 2001-2002 Hybrid Development Team
7			*
8			* Code borrowed from the squid web cache by Adrian Chadd.
9			* Original header:
10			*
11			* DEBUG: section 41 Event Processing
12			* AUTHOR: Henrik Nordstrom
13			*
14			* SQUID Internet Object Cache http://squid.nlanr.net/Squid/
15			* ----------------------------------------------------------
16			*
17			* Squid is the result of efforts by numerous individuals from the
18			* Internet community. Development is led by Duane Wessels of the
19			* National Laboratory for Applied Network Research and funded by the
20			* National Science Foundation. Squid is Copyrighted (C) 1998 by
21			* the Regents of the University of California. Please see the
22			* COPYRIGHT file for full details. Squid incorporates software
23			* developed and/or copyrighted by other sources. Please see the
24			* CREDITS file for full details.
25			*
26			* This program is free software; you can redistribute it and/or modify
27			* it under the terms of the GNU General Public License as published by
28			* the Free Software Foundation; either version 2 of the License, or
29			* (at your option) any later version.
30			*
31			* This program is distributed in the hope that it will be useful,
32			* but WITHOUT ANY WARRANTY; without even the implied warranty of
33			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
34			* GNU General Public License for more details.
35			*
36			* You should have received a copy of the GNU General Public License
37			* along with this program; if not, write to the Free Software
38			* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
39			* USA
40			*
41			* $Id: event.c 33 2005-10-02 20:50:00Z knight $
42			*/
43
44			/*
45			* How it's used:
46			*
47			* Should be pretty self-explanatory. Events are added to the static
48			* array event_table with a frequency time telling eventRun how often
49			* to execute it.
50			*/
51
52			#include "stdinc.h"
53
54	adx	65	const char *last_event_ran = NULL;
55			struct ev_entry event_table[MAX_EVENTS];
56
57	adx	61	static time_t event_time_min = -1;
58			static int eventFind(EVH func, void arg);
59
60			/*
61			* void eventAdd(const char name, EVH func, void *arg, time_t when)
62			*
63			* Input: Name of event, function to call, arguments to pass, and frequency
64			* of the event.
65			* Output: None
66			* Side Effects: Adds the event to the event list.
67			*/
68			void
69			eventAdd(const char name, EVH func, void *arg, time_t when)
70			{
71			int i;
72
73			/* find first inactive index, or use next index */
74			for (i = 0; i < MAX_EVENTS; i++)
75			{
76			if (event_table[i].active == 0)
77			{
78			event_table[i].func = func;
79			event_table[i].name = name;
80			event_table[i].arg = arg;
81			event_table[i].when = CurrentTime + when;
82			event_table[i].frequency = when;
83			event_table[i].active = 1;
84
85			if ((event_table[i].when < event_time_min) \|\| (event_time_min == -1))
86			event_time_min = event_table[i].when;
87
88			return;
89			}
90			}
91			/* XXX if reach here, its an error */
92			ilog(L_ERROR, "Event table is full! (%d)", i);
93			}
94
95			/*
96			* void eventDelete(EVH func, void arg)
97			*
98			* Input: Function handler, argument that was passed.
99			* Output: None
100			* Side Effects: Removes the event from the event list
101			*/
102			void
103			eventDelete(EVH func, void arg)
104			{
105			int i = eventFind(func, arg);
106
107			if (i == -1)
108			return;
109
110			event_table[i].name = NULL;
111			event_table[i].func = NULL;
112			event_table[i].arg = NULL;
113			event_table[i].active = 0;
114			}
115
116			/*
117			* void eventAddIsh(const char name, EVH func, void *arg, time_t delta_isa)
118			*
119			* Input: Name of event, function to call, arguments to pass, and frequency
120			* of the event.
121			* Output: None
122			* Side Effects: Adds the event to the event list within +- 1/3 of the
123			* specified frequency.
124			*/
125			void
126			eventAddIsh(const char name, EVH func, void *arg, time_t delta_ish)
127			{
128			if (delta_ish >= 3.0)
129			{
130			const time_t two_third = (2 * delta_ish) / 3;
131			delta_ish = two_third + ((rand() % 1000) * two_third) / 1000;
132			/*
133			* XXX I hate the above magic, I don't even know if its right.
134			* Grr. -- adrian
135			*/
136			}
137
138			eventAdd(name, func, arg, delta_ish);
139			}
140
141			/*
142			* void eventRun(void)
143			*
144			* Input: None
145			* Output: None
146			* Side Effects: Runs pending events in the event list
147			*/
148			void
149			eventRun(void)
150			{
151			int i;
152
153			for (i = 0; i < MAX_EVENTS; i++)
154			{
155			if (event_table[i].active && (event_table[i].when <= CurrentTime))
156			{
157			last_event_ran = event_table[i].name;
158			event_table[i].func(event_table[i].arg);
159			event_table[i].when = CurrentTime + event_table[i].frequency;
160			event_time_min = -1;
161			}
162			}
163			}
164
165			/*
166			* time_t eventNextTime(void)
167			*
168			* Input: None
169			* Output: Specifies the next time eventRun() should be run
170			* Side Effects: None
171			*/
172			time_t
173			eventNextTime(void)
174			{
175			int i;
176
177			if (event_time_min == -1)
178			{
179			for (i = 0; i < MAX_EVENTS; i++)
180			{
181			if (event_table[i].active && ((event_table[i].when < event_time_min) \|\| (event_time_min == -1)))
182			event_time_min = event_table[i].when;
183			}
184			}
185
186	adx	65	return event_time_min;
187	adx	61	}
188
189			/*
190			* void eventInit(void)
191			*
192			* Input: None
193			* Output: None
194			* Side Effects: Initializes the event system.
195			*/
196			void
197			eventInit(void)
198			{
199			last_event_ran = NULL;
200			memset(event_table, 0, sizeof(event_table));
201			}
202
203			/*
204			* int eventFind(EVH func, void arg)
205			*
206			* Input: Event function and the argument passed to it
207			* Output: Index to the slow in the event_table
208			* Side Effects: None
209			*/
210			static int
211			eventFind(EVH func, void arg)
212			{
213			int i;
214
215			for (i = 0; i < MAX_EVENTS; i++)
216			{
217			if ((event_table[i].func == func) &&
218			(event_table[i].arg == arg) &&
219			event_table[i].active)
220	adx	65	return i;
221	adx	61	}
222
223	adx	65	return -1;
224	adx	61	}
225
226			/*
227			* void set_back_events(time_t by)
228			* Input: Time to set back events by.
229			* Output: None.
230			* Side-effects: Sets back all events by "by" seconds.
231			*/
232			void
233			set_back_events(time_t by)
234			{
235			int i;
236
237			for (i = 0; i < MAX_EVENTS; i++)
238			{
239			if (event_table[i].when > by)
240			event_table[i].when -= by;
241			else
242			event_table[i].when = 0;
243			}
244			}