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more TODOs
[disorder] / clients / playrtp-mem.c
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8e3fe3d8 1/*
2 * This file is part of DisOrder.
3 * Copyright (C) 2007 Richard Kettlewell
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
18 * USA
19 */
20/** @file clients/playrtp-mem.c
21 * @brief RTP player memory management
22 */
23
05b75f8d 24#include "common.h"
8e3fe3d8 25
26#include <pthread.h>
8e3fe3d8 27
28#include "mem.h"
29#include "vector.h"
30#include "heap.h"
31#include "playrtp.h"
32
33/** @brief Linked list of free packets
34 *
35 * This is a linked list of formerly used packets. For preference we re-use
36 * packets that have already been used rather than unused ones, to limit the
37 * size of the program's working set. If there are no free packets in the list
38 * we try @ref next_free_packet instead.
39 *
40 * Must hold @ref lock when accessing this.
41 */
42static union free_packet *free_packets;
43
44/** @brief Array of new free packets
45 *
46 * There are @ref count_free_packets ready to use at this address. If there
47 * are none left we allocate more memory.
48 *
49 * Must hold @ref lock when accessing this.
50 */
51static union free_packet *next_free_packet;
52
53/** @brief Count of new free packets at @ref next_free_packet
54 *
55 * Must hold @ref lock when accessing this.
56 */
57static size_t count_free_packets;
58
59/** @brief Lock protecting packet allocator */
60static pthread_mutex_t mem_lock = PTHREAD_MUTEX_INITIALIZER;
61
62/** @brief Return a new packet */
c593cf7c 63struct packet *playrtp_new_packet(void) {
8e3fe3d8 64 struct packet *p;
65
66 pthread_mutex_lock(&mem_lock);
67 if(free_packets) {
68 p = &free_packets->p;
69 free_packets = free_packets->next;
70 } else {
71 if(!count_free_packets) {
72 next_free_packet = xcalloc(1024, sizeof (union free_packet));
73 count_free_packets = 1024;
74 }
75 p = &(next_free_packet++)->p;
76 --count_free_packets;
77 }
78 pthread_mutex_unlock(&mem_lock);
79 return p;
80}
81
82/** @brief Free a packet */
c593cf7c 83void playrtp_free_packet(struct packet *p) {
8e3fe3d8 84 union free_packet *u = (union free_packet *)p;
85 pthread_mutex_lock(&mem_lock);
86 u->next = free_packets;
87 free_packets = u;
88 pthread_mutex_unlock(&mem_lock);
89}
90
91
92/*
93Local Variables:
94c-basic-offset:2
95comment-column:40
96fill-column:79
97indent-tabs-mode:nil
98End:
99*/