trunk/src/dbuf.c

/*
 *  ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd)
 *
 *  Copyright (c) 1997-2014 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 *  USA
 */

/*! \file dbuf.c
 * \brief Supports dynamic data buffers.
 * \version $Id$
 */

#include "stdinc.h"
#include "list.h"
#include "dbuf.h"
#include "memory.h"
#include "mempool.h"

static mp_pool_t *dbuf_pool;

void
dbuf_init(void)
{
  dbuf_pool = mp_pool_new(sizeof(struct dbuf_block), MP_CHUNK_SIZE_DBUF);
}

void
dbuf_add(struct dbuf_queue *qptr, struct dbuf_block *bptr)
{
  assert(bptr->size > 0);

  bptr->refs++;
  dlinkAddTail(bptr, make_dlink_node(), &qptr->blocks);

  qptr->total_size += bptr->size;
}

void
dbuf_delete(struct dbuf_queue *qptr, size_t count)
{
  assert(qptr->total_size >= count);

  qptr->total_size -= count;

  while (count > 0 && dlink_list_length(&qptr->blocks) > 0)
  {
    dlink_node *node = qptr->blocks.head;
    struct dbuf_block *buffer = node->data;
    size_t avail;

    assert(buffer->size > qptr->pos);
    avail = buffer->size - qptr->pos;

    if (count >= avail)
    {
      count -= avail;

      dbuf_ref_free(buffer);

      dlinkDelete(node, &qptr->blocks);
      free_dlink_node(node);

      qptr->pos = 0;

    }
    else
    {
      qptr->pos += count;
      count = 0;
    }
  }
}

struct dbuf_block *
dbuf_alloc(void)
{
  struct dbuf_block *block = mp_pool_get(dbuf_pool);

  memset(block, 0, sizeof(*block));

  ++block->refs;
  return block;
}

void
dbuf_ref_free(struct dbuf_block *bptr)
{
  if (--bptr->refs <= 0)
    mp_pool_release(bptr);
}

void
dbuf_put(struct dbuf_block *dbuf, const char *pattern, ...)
{
  va_list args;

  assert(dbuf->refs == 1);

  va_start(args, pattern);
  dbuf_put_args(dbuf, pattern, args);
  va_end(args);
}

void
dbuf_put_args(struct dbuf_block *dbuf, const char *data, va_list args)
{
  assert(dbuf->refs == 1);

  dbuf->size += vsnprintf(dbuf->data + dbuf->size, sizeof(dbuf->data) - dbuf->size, data, args);

  if (dbuf->size > sizeof(dbuf->data))
    dbuf->size = sizeof(dbuf->data);  /* Required by some versions of vsnprintf */
}

void
dbuf_put_raw(struct dbuf_queue *qptr, const char *buf, size_t sz)
{
  struct dbuf_block *buffer;

  assert(sz > 0);

  if (dlink_list_length(&qptr->blocks) == 0)
  {
    buffer = dbuf_alloc();
    dlinkAddTail(buffer, make_dlink_node(), &qptr->blocks);
    assert(qptr->pos == 0);
  }

  do
  {
    size_t amount;

    buffer = qptr->blocks.tail->data;
    amount = sizeof(buffer->data) - buffer->size;

    if (!amount)
    {
      buffer = dbuf_alloc();
      dlinkAddTail(buffer, make_dlink_node(), &qptr->blocks);
    }

    if (amount > sz)
      amount = sz;

    memcpy(&buffer->data[buffer->size], buf, amount);
    buffer->size += amount;

    qptr->total_size += amount;
    sz -= amount;
    buf += amount;
  } while (sz > 0);
}

Revision:	3107
Committed:	Thu Mar 6 12:09:42 2014 UTC (12 years, 4 months ago) by michael
Content type:	text/x-csrc
File size:	3547 byte(s)
Log Message:	- Applied dbuf changes as provided by Adam: Refcount dbufs instead of copying the same message to many different buffers.
#	User	Rev	Content
1	adx	30	/*
2	michael	2916	* ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd)
3	adx	30	*
4	michael	2916	* Copyright (c) 1997-2014 ircd-hybrid development team
5	adx	30	*
6			* This program is free software; you can redistribute it and/or modify
7			* it under the terms of the GNU General Public License as published by
8			* the Free Software Foundation; either version 2 of the License, or
9			* (at your option) any later version.
10			*
11			* This program is distributed in the hope that it will be useful,
12			* but WITHOUT ANY WARRANTY; without even the implied warranty of
13			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14			* GNU General Public License for more details.
15			*
16			* You should have received a copy of the GNU General Public License
17			* along with this program; if not, write to the Free Software
18			* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
19			* USA
20			*/
21
22	michael	2916	/*! \file dbuf.c
23			* \brief Supports dynamic data buffers.
24			* \version $Id$
25			*/
26
27	adx	30	#include "stdinc.h"
28	michael	1011	#include "list.h"
29	adx	30	#include "dbuf.h"
30			#include "memory.h"
31	michael	1654	#include "mempool.h"
32	adx	30
33	michael	1654	static mp_pool_t *dbuf_pool;
34	adx	30
35			void
36			dbuf_init(void)
37			{
38	michael	1654	dbuf_pool = mp_pool_new(sizeof(struct dbuf_block), MP_CHUNK_SIZE_DBUF);
39	adx	30	}
40
41	michael	3107	void
42			dbuf_add(struct dbuf_queue qptr, struct dbuf_block bptr)
43	adx	30	{
44	michael	3107	assert(bptr->size > 0);
45
46			bptr->refs++;
47			dlinkAddTail(bptr, make_dlink_node(), &qptr->blocks);
48
49			qptr->total_size += bptr->size;
50			}
51
52			void
53			dbuf_delete(struct dbuf_queue *qptr, size_t count)
54			{
55			assert(qptr->total_size >= count);
56
57			qptr->total_size -= count;
58
59			while (count > 0 && dlink_list_length(&qptr->blocks) > 0)
60			{
61			dlink_node *node = qptr->blocks.head;
62			struct dbuf_block *buffer = node->data;
63			size_t avail;
64
65			assert(buffer->size > qptr->pos);
66			avail = buffer->size - qptr->pos;
67
68			if (count >= avail)
69			{
70			count -= avail;
71
72			dbuf_ref_free(buffer);
73
74			dlinkDelete(node, &qptr->blocks);
75			free_dlink_node(node);
76
77			qptr->pos = 0;
78
79			}
80			else
81			{
82			qptr->pos += count;
83			count = 0;
84			}
85			}
86			}
87
88			struct dbuf_block *
89			dbuf_alloc(void)
90			{
91	michael	1654	struct dbuf_block *block = mp_pool_get(dbuf_pool);
92	adx	30
93	michael	1654	memset(block, 0, sizeof(*block));
94	michael	3107
95			++block->refs;
96	adx	30	return block;
97			}
98
99			void
100	michael	3107	dbuf_ref_free(struct dbuf_block *bptr)
101	adx	30	{
102	michael	3107	if (--bptr->refs <= 0)
103			mp_pool_release(bptr);
104			}
105	adx	30
106	michael	3107	void
107			dbuf_put(struct dbuf_block dbuf, const char pattern, ...)
108			{
109			va_list args;
110	adx	30
111	michael	3107	assert(dbuf->refs == 1);
112	adx	30
113	michael	3107	va_start(args, pattern);
114			dbuf_put_args(dbuf, pattern, args);
115			va_end(args);
116			}
117	adx	30
118	michael	3107	void
119			dbuf_put_args(struct dbuf_block dbuf, const char data, va_list args)
120			{
121			assert(dbuf->refs == 1);
122	adx	30
123	michael	3107	dbuf->size += vsnprintf(dbuf->data + dbuf->size, sizeof(dbuf->data) - dbuf->size, data, args);
124	adx	30
125	michael	3107	if (dbuf->size > sizeof(dbuf->data))
126			dbuf->size = sizeof(dbuf->data); /* Required by some versions of vsnprintf */
127	adx	30	}
128
129			void
130	michael	3107	dbuf_put_raw(struct dbuf_queue qptr, const char buf, size_t sz)
131	adx	30	{
132	michael	3107	struct dbuf_block *buffer;
133	adx	30
134	michael	3107	assert(sz > 0);
135	adx	30
136	michael	3107	if (dlink_list_length(&qptr->blocks) == 0)
137	adx	30	{
138	michael	3107	buffer = dbuf_alloc();
139			dlinkAddTail(buffer, make_dlink_node(), &qptr->blocks);
140			assert(qptr->pos == 0);
141	adx	30	}
142
143	michael	3107	do
144			{
145			size_t amount;
146
147			buffer = qptr->blocks.tail->data;
148			amount = sizeof(buffer->data) - buffer->size;
149
150			if (!amount)
151			{
152			buffer = dbuf_alloc();
153			dlinkAddTail(buffer, make_dlink_node(), &qptr->blocks);
154			}
155
156			if (amount > sz)
157			amount = sz;
158
159			memcpy(&buffer->data[buffer->size], buf, amount);
160			buffer->size += amount;
161
162			qptr->total_size += amount;
163			sz -= amount;
164			buf += amount;
165			} while (sz > 0);
166	adx	30	}
167