fftools/objpool.c

   1 /*
   2  * This file is part of FFmpeg.
   3  *
   4  * FFmpeg is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * FFmpeg is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with FFmpeg; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  17  */
  18
  19 #include <stdint.h>
  20
  21 #include "libavcodec/packet.h"
  22
  23 #include "libavutil/common.h"
  24 #include "libavutil/error.h"
  25 #include "libavutil/frame.h"
  26 #include "libavutil/mem.h"
  27
  28 #include "objpool.h"
  29
  30 struct ObjPool {
  31     void        *pool[32];
  32     unsigned int pool_count;
  33
  34     ObjPoolCBAlloc alloc;
  35     ObjPoolCBReset reset;
  36     ObjPoolCBFree  free;
  37 };
  38
  39 ObjPool *objpool_alloc(ObjPoolCBAlloc cb_alloc, ObjPoolCBReset cb_reset,
  40                        ObjPoolCBFree cb_free)
  41 {
  42     ObjPool *op = av_mallocz(sizeof(*op));
  43
  44     if (!op)
  45         return NULL;
  46
  47     op->alloc = cb_alloc;
  48     op->reset = cb_reset;
  49     op->free  = cb_free;
  50
  51     return op;
  52 }
  53
  54 void objpool_free(ObjPool **pop)
  55 {
  56     ObjPool *op = *pop;
  57
  58     if (!op)
  59         return;
  60
  61     for (unsigned int i = 0; i < op->pool_count; i++)
  62         op->free(&op->pool[i]);
  63
  64     av_freep(pop);
  65 }
  66
  67 int  objpool_get(ObjPool *op, void **obj)
  68 {
  69     if (op->pool_count) {
  70         *obj = op->pool[--op->pool_count];
  71         op->pool[op->pool_count] = NULL;
  72     } else
  73         *obj = op->alloc();
  74
  75     return *obj ? 0 : AVERROR(ENOMEM);
  76 }
  77
  78 void objpool_release(ObjPool *op, void **obj)
  79 {
  80     if (!*obj)
  81         return;
  82
  83     op->reset(*obj);
  84
  85     if (op->pool_count < FF_ARRAY_ELEMS(op->pool))
  86         op->pool[op->pool_count++] = *obj;
  87     else
  88         op->free(obj);
  89
  90     *obj = NULL;
  91 }
  92
  93 static void *alloc_packet(void)
  94 {
  95     return av_packet_alloc();
  96 }
  97 static void *alloc_frame(void)
  98 {
  99     return av_frame_alloc();
 100 }
 101
 102 static void reset_packet(void *obj)
 103 {
 104     av_packet_unref(obj);
 105 }
 106 static void reset_frame(void *obj)
 107 {
 108     av_frame_unref(obj);
 109 }
 110
 111 static void free_packet(void **obj)
 112 {
 113     AVPacket *pkt = *obj;
 114     av_packet_free(&pkt);
 115     *obj = NULL;
 116 }
 117 static void free_frame(void **obj)
 118 {
 119     AVFrame *frame = *obj;
 120     av_frame_free(&frame);
 121     *obj = NULL;
 122 }
 123
 124 ObjPool *objpool_alloc_packets(void)
 125 {
 126     return objpool_alloc(alloc_packet, reset_packet, free_packet);
 127 }
 128 ObjPool *objpool_alloc_frames(void)
 129 {
 130     return objpool_alloc(alloc_frame, reset_frame, free_frame);
 131 }