trunk/src/watch.c

/*
 *  ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd)
 *
 *  Copyright (c) 1997 Jukka Santala (Donwulff)
 *  Copyright (c) 2005-2018 ircd-hybrid development 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, Fifth Floor, Boston, MA 02110-1301
 *  USA
 */

/*! \file watch.c
 * \brief File including functions for WATCH support
 * \version $Id$
 */

#include "stdinc.h"
#include "list.h"
#include "memory.h"
#include "client.h"
#include "hash.h"
#include "irc_string.h"
#include "ircd.h"
#include "numeric.h"
#include "send.h"
#include "watch.h"


static dlink_list watchTable[HASHSIZE];


/*
 * Rough figure of the datastructures for watch:
 *
 * NOTIFY HASH          client_p1
 *   |                    |- nick1
 * nick1-|- client_p1     |- nick2
 *   |   |- client_p2                client_p3
 *   |   |- client_p3   client_p2      |- nick1
 *   |                    |- nick1
 * nick2-|- client_p2     |- nick2
 *       |- client_p1
 */

/*! \brief Counts up memory used by watch list headers
 */
void
watch_count_memory(unsigned int *const count, size_t *const bytes)
{
  for (unsigned int i = 0; i < HASHSIZE; ++i)
    (*count) += dlink_list_length(&watchTable[i]);

  (*bytes) = *count * sizeof(struct Watch);
}

/*! \brief Notifies all clients that have client_p's name on
 *         their watch list.
 * \param client_p Pointer to Client struct
 * \param reply Numeric to send. Either RPL_LOGON or RPL_LOGOFF
 */
void
watch_check_hash(const struct Client *client_p, const enum irc_numerics reply)
{
  struct Watch *watch = NULL;
  dlink_node *node = NULL;

  assert(IsClient(client_p));

  if ((watch = watch_find_hash(client_p->name)) == NULL)
    return;  /* This name isn't on watch */

  /* Update the time of last change to item */
  watch->lasttime = CurrentTime;

  /* Send notifies out to everybody on the list in header */
  DLINK_FOREACH(node, watch->watched_by.head)
    sendto_one_numeric(node->data, &me, reply, client_p->name,
                       client_p->username, client_p->host,
                       watch->lasttime, client_p->info);
}

/*! \brief Looks up the watch table for a given name
 * \param name Nick name to look up
 */
struct Watch *
watch_find_hash(const char *name)
{
  dlink_node *node = NULL;

  DLINK_FOREACH(node, watchTable[strhash(name)].head)
  {
    struct Watch *watch = node->data;

    if (irccmp(watch->name, name) == 0)
      return watch;
  }

  return NULL;
}

/*! \brief Adds a watch entry to client_p's watch list
 * \param name     Nick name to add
 * \param client_p Pointer to Client struct
 */
void
watch_add_to_hash_table(const char *name, struct Client *client_p)
{
  struct Watch *watch = NULL;
  dlink_node *node = NULL;

  /* If found NULL (no header for this name), make one... */
  if ((watch = watch_find_hash(name)) == NULL)
  {
    watch = xcalloc(sizeof(*watch));

    strlcpy(watch->name, name, sizeof(watch->name));
    watch->hash_value = strhash(watch->name);
    watch->lasttime = CurrentTime;

    dlinkAdd(watch, &watch->node, &watchTable[watch->hash_value]);
  }
  else
  {
    /* Is this client already on the watch-list? */
    node = dlinkFind(&watch->watched_by, client_p);
  }

  if (node == NULL)
  {
    /* No it isn't, so add it in the bucket and client adding it */
    dlinkAdd(client_p, make_dlink_node(), &watch->watched_by);
    dlinkAdd(watch, make_dlink_node(), &client_p->connection->watches);
  }
}

/*! \brief Removes a single entry from client_p's watch list
 * \param name     Name to remove
 * \param client_p Pointer to Client struct
 */
void
watch_del_from_hash_table(const char *name, struct Client *client_p)
{
  struct Watch *watch = NULL;
  dlink_node *node = NULL;

  if ((watch = watch_find_hash(name)) == NULL)
    return;  /* No header found for that name. i.e. it's not being watched */

  if ((node = dlinkFind(&watch->watched_by, client_p)) == NULL)
    return;  /* This name isn't being watched by client_p */

  dlinkDelete(node, &watch->watched_by);
  free_dlink_node(node);

  if ((node = dlinkFindDelete(&client_p->connection->watches, watch)))
    free_dlink_node(node);

  /* In case this header is now empty of notices, remove it */
  if (watch->watched_by.head == NULL)
  {
    assert(dlinkFind(&watchTable[watch->hash_value], watch));
    dlinkDelete(&watch->node, &watchTable[watch->hash_value]);
    xfree(watch);
  }
}

/*! \brief Removes all entries from client_p's watch list
 *         and deletes headers that are no longer being watched.
 * \param client_p Pointer to Client struct
 */
void
watch_del_watch_list(struct Client *client_p)
{
  dlink_node *node = NULL, *node_next = NULL;
  dlink_node *temp = NULL;

  DLINK_FOREACH_SAFE(node, node_next, client_p->connection->watches.head)
  {
    struct Watch *watch = node->data;

    assert(dlinkFind(&watch->watched_by, client_p));

    if ((temp = dlinkFindDelete(&watch->watched_by, client_p)))
      free_dlink_node(temp);

    /* If this leaves a header without notifies, remove it. */
    if (watch->watched_by.head == NULL)
    {
      assert(dlinkFind(&watchTable[watch->hash_value], watch));
      dlinkDelete(&watch->node, &watchTable[watch->hash_value]);

      xfree(watch);
    }

    dlinkDelete(node, &client_p->connection->watches);
    free_dlink_node(node);
  }

  assert(client_p->connection->watches.head == NULL);
  assert(client_p->connection->watches.tail == NULL);
}
Revision:	8590
Committed:	Sun Oct 21 15:44:08 2018 UTC (6 years, 10 months ago) by michael
Content type:	text/x-csrc
File size:	6046 byte(s)
Log Message:	- watch: cache hash values
#	User	Rev	Content
1	michael	876	/*
2	michael	2855	* ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd)
3	michael	876	*
4	michael	2855	* Copyright (c) 1997 Jukka Santala (Donwulff)
5	michael	8279	* Copyright (c) 2005-2018 ircd-hybrid development team
6	michael	876	*
7			* This program is free software; you can redistribute it and/or modify
8			* it under the terms of the GNU General Public License as published by
9			* the Free Software Foundation; either version 2 of the License, or
10			* (at your option) any later version.
11			*
12			* This program is distributed in the hope that it will be useful,
13			* but WITHOUT ANY WARRANTY; without even the implied warranty of
14			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15			* GNU General Public License for more details.
16			*
17			* You should have received a copy of the GNU General Public License
18			* along with this program; if not, write to the Free Software
19	michael	4565	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
20	michael	876	* USA
21			*/
22
23			/*! \file watch.c
24			* \brief File including functions for WATCH support
25	michael	879	* \version $Id$
26	michael	876	*/
27
28			#include "stdinc.h"
29	michael	1011	#include "list.h"
30	michael	8385	#include "memory.h"
31	michael	876	#include "client.h"
32			#include "hash.h"
33			#include "irc_string.h"
34			#include "ircd.h"
35			#include "numeric.h"
36			#include "send.h"
37			#include "watch.h"
38
39
40			static dlink_list watchTable[HASHSIZE];
41
42
43			/*
44			* Rough figure of the datastructures for watch:
45			*
46			* NOTIFY HASH client_p1
47			* \| \|- nick1
48			* nick1-\|- client_p1 \|- nick2
49			* \| \|- client_p2 client_p3
50			* \| \|- client_p3 client_p2 \|- nick1
51			* \| \|- nick1
52			* nick2-\|- client_p2 \|- nick2
53			* \|- client_p1
54			*/
55
56			/*! \brief Counts up memory used by watch list headers
57			*/
58			void
59	michael	6719	watch_count_memory(unsigned int const count, size_t const bytes)
60	michael	876	{
61	michael	3250	for (unsigned int i = 0; i < HASHSIZE; ++i)
62			(*count) += dlink_list_length(&watchTable[i]);
63	michael	876
64	michael	2297	(bytes) = count * sizeof(struct Watch);
65	michael	876	}
66
67	michael	7084	/*! \brief Notifies all clients that have client_p's name on
68	michael	876	* their watch list.
69	michael	2855	* \param client_p Pointer to Client struct
70			* \param reply Numeric to send. Either RPL_LOGON or RPL_LOGOFF
71	michael	876	*/
72			void
73	michael	4785	watch_check_hash(const struct Client *client_p, const enum irc_numerics reply)
74	michael	876	{
75	michael	4815	struct Watch *watch = NULL;
76	michael	4800	dlink_node *node = NULL;
77	michael	3250
78	michael	876	assert(IsClient(client_p));
79	michael	3250
80	michael	4815	if ((watch = watch_find_hash(client_p->name)) == NULL)
81	michael	7084	return; /* This name isn't on watch */
82	michael	876
83	michael	1359	/* Update the time of last change to item */
84	michael	4815	watch->lasttime = CurrentTime;
85	michael	876
86	michael	1359	/* Send notifies out to everybody on the list in header */
87	michael	4815	DLINK_FOREACH(node, watch->watched_by.head)
88	michael	4800	sendto_one_numeric(node->data, &me, reply, client_p->name,
89	michael	3109	client_p->username, client_p->host,
90	michael	4815	watch->lasttime, client_p->info);
91	michael	876	}
92
93	michael	7084	/*! \brief Looks up the watch table for a given name
94	michael	2855	* \param name Nick name to look up
95	michael	876	*/
96			struct Watch *
97			watch_find_hash(const char *name)
98			{
99	michael	4800	dlink_node *node = NULL;
100	michael	876
101	michael	4800	DLINK_FOREACH(node, watchTable[strhash(name)].head)
102	michael	876	{
103	michael	4815	struct Watch *watch = node->data;
104	michael	876
105	michael	8512	if (irccmp(watch->name, name) == 0)
106	michael	4815	return watch;
107	michael	876	}
108
109			return NULL;
110			}
111
112			/*! \brief Adds a watch entry to client_p's watch list
113	michael	7084	* \param name Nick name to add
114	michael	876	* \param client_p Pointer to Client struct
115			*/
116			void
117	michael	7084	watch_add_to_hash_table(const char name, struct Client client_p)
118	michael	876	{
119	michael	4815	struct Watch *watch = NULL;
120	michael	4800	dlink_node *node = NULL;
121	michael	876
122	michael	7084	/* If found NULL (no header for this name), make one... */
123			if ((watch = watch_find_hash(name)) == NULL)
124	michael	876	{
125	michael	8385	watch = xcalloc(sizeof(*watch));
126	michael	3250
127	michael	8590	strlcpy(watch->name, name, sizeof(watch->name));
128			watch->hash_value = strhash(watch->name);
129	michael	4815	watch->lasttime = CurrentTime;
130	michael	876
131	michael	8590	dlinkAdd(watch, &watch->node, &watchTable[watch->hash_value]);
132	michael	876	}
133			else
134			{
135	michael	1359	/* Is this client already on the watch-list? */
136	michael	4815	node = dlinkFind(&watch->watched_by, client_p);
137	michael	876	}
138
139	michael	4800	if (node == NULL)
140	michael	876	{
141	michael	4728	/* No it isn't, so add it in the bucket and client adding it */
142	michael	4815	dlinkAdd(client_p, make_dlink_node(), &watch->watched_by);
143			dlinkAdd(watch, make_dlink_node(), &client_p->connection->watches);
144	michael	876	}
145			}
146
147			/*! \brief Removes a single entry from client_p's watch list
148	michael	7084	* \param name Name to remove
149	michael	876	* \param client_p Pointer to Client struct
150			*/
151			void
152	michael	7084	watch_del_from_hash_table(const char name, struct Client client_p)
153	michael	876	{
154	michael	4815	struct Watch *watch = NULL;
155	michael	4800	dlink_node *node = NULL;
156	michael	876
157	michael	7084	if ((watch = watch_find_hash(name)) == NULL)
158			return; /* No header found for that name. i.e. it's not being watched */
159	michael	876
160	michael	4815	if ((node = dlinkFind(&watch->watched_by, client_p)) == NULL)
161	michael	7084	return; /* This name isn't being watched by client_p */
162	michael	876
163	michael	4815	dlinkDelete(node, &watch->watched_by);
164	michael	4800	free_dlink_node(node);
165	michael	876
166	michael	4815	if ((node = dlinkFindDelete(&client_p->connection->watches, watch)))
167	michael	4800	free_dlink_node(node);
168	michael	876
169	michael	1359	/* In case this header is now empty of notices, remove it */
170	michael	4815	if (watch->watched_by.head == NULL)
171	michael	876	{
172	michael	8590	assert(dlinkFind(&watchTable[watch->hash_value], watch));
173			dlinkDelete(&watch->node, &watchTable[watch->hash_value]);
174	michael	8385	xfree(watch);
175	michael	876	}
176			}
177
178			/*! \brief Removes all entries from client_p's watch list
179			* and deletes headers that are no longer being watched.
180			* \param client_p Pointer to Client struct
181			*/
182			void
183			watch_del_watch_list(struct Client *client_p)
184			{
185	michael	4800	dlink_node node = NULL, node_next = NULL;
186			dlink_node *temp = NULL;
187	michael	876
188	michael	4800	DLINK_FOREACH_SAFE(node, node_next, client_p->connection->watches.head)
189	michael	876	{
190	michael	4815	struct Watch *watch = node->data;
191	michael	876
192	michael	4815	assert(dlinkFind(&watch->watched_by, client_p));
193	michael	876
194	michael	4815	if ((temp = dlinkFindDelete(&watch->watched_by, client_p)))
195	michael	4800	free_dlink_node(temp);
196	michael	876
197	michael	1359	/* If this leaves a header without notifies, remove it. */
198	michael	4815	if (watch->watched_by.head == NULL)
199	michael	876	{
200	michael	8590	assert(dlinkFind(&watchTable[watch->hash_value], watch));
201			dlinkDelete(&watch->node, &watchTable[watch->hash_value]);
202	michael	876
203	michael	8385	xfree(watch);
204	michael	876	}
205
206	michael	4800	dlinkDelete(node, &client_p->connection->watches);
207			free_dlink_node(node);
208	michael	876	}
209
210	michael	4588	assert(client_p->connection->watches.head == NULL);
211			assert(client_p->connection->watches.tail == NULL);
212	michael	876	}