| 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 3 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, |
| 11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | * GNU 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, see <http://www.gnu.org/licenses/>. |
| 17 | */ |
| 18 | /** @file clients/playrtp-mem.c |
| 19 | * @brief RTP player memory management |
| 20 | */ |
| 21 | |
| 22 | #include "common.h" |
| 23 | |
| 24 | #include <pthread.h> |
| 25 | |
| 26 | #include "mem.h" |
| 27 | #include "vector.h" |
| 28 | #include "heap.h" |
| 29 | #include "playrtp.h" |
| 30 | |
| 31 | /** @brief Linked list of free packets |
| 32 | * |
| 33 | * This is a linked list of formerly used packets. For preference we re-use |
| 34 | * packets that have already been used rather than unused ones, to limit the |
| 35 | * size of the program's working set. If there are no free packets in the list |
| 36 | * we try @ref next_free_packet instead. |
| 37 | * |
| 38 | * Must hold @ref lock when accessing this. |
| 39 | */ |
| 40 | static union free_packet *free_packets; |
| 41 | |
| 42 | /** @brief Array of new free packets |
| 43 | * |
| 44 | * There are @ref count_free_packets ready to use at this address. If there |
| 45 | * are none left we allocate more memory. |
| 46 | * |
| 47 | * Must hold @ref lock when accessing this. |
| 48 | */ |
| 49 | static union free_packet *next_free_packet; |
| 50 | |
| 51 | /** @brief Count of new free packets at @ref next_free_packet |
| 52 | * |
| 53 | * Must hold @ref lock when accessing this. |
| 54 | */ |
| 55 | static size_t count_free_packets; |
| 56 | |
| 57 | /** @brief Lock protecting packet allocator */ |
| 58 | static pthread_mutex_t mem_lock = PTHREAD_MUTEX_INITIALIZER; |
| 59 | |
| 60 | /** @brief Return a new packet */ |
| 61 | struct packet *playrtp_new_packet(void) { |
| 62 | struct packet *p; |
| 63 | |
| 64 | pthread_mutex_lock(&mem_lock); |
| 65 | if(free_packets) { |
| 66 | p = &free_packets->p; |
| 67 | free_packets = free_packets->next; |
| 68 | } else { |
| 69 | if(!count_free_packets) { |
| 70 | next_free_packet = xcalloc(1024, sizeof (union free_packet)); |
| 71 | count_free_packets = 1024; |
| 72 | } |
| 73 | p = &(next_free_packet++)->p; |
| 74 | --count_free_packets; |
| 75 | } |
| 76 | pthread_mutex_unlock(&mem_lock); |
| 77 | return p; |
| 78 | } |
| 79 | |
| 80 | /** @brief Free a packet */ |
| 81 | void playrtp_free_packet(struct packet *p) { |
| 82 | union free_packet *u = (union free_packet *)p; |
| 83 | pthread_mutex_lock(&mem_lock); |
| 84 | u->next = free_packets; |
| 85 | free_packets = u; |
| 86 | pthread_mutex_unlock(&mem_lock); |
| 87 | } |
| 88 | |
| 89 | |
| 90 | /* |
| 91 | Local Variables: |
| 92 | c-basic-offset:2 |
| 93 | comment-column:40 |
| 94 | fill-column:79 |
| 95 | indent-tabs-mode:nil |
| 96 | End: |
| 97 | */ |