src/misc/picture_fifo.c

   1 /*****************************************************************************
   2  * picture_fifo.c : picture fifo functions
   3  *****************************************************************************
   4  * Copyright (C) 2009 the VideoLAN team
   5  * Copyright (C) 2009 Laurent Aimar <fenrir _AT_ videolan _DOT_ org>
   6  * $Id$
   7  *
   8  * Authors: Laurent Aimar <fenrir _AT_ videolan _DOT_ org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  23  *****************************************************************************/
  24
  25 /*****************************************************************************
  26  * Preamble
  27  *****************************************************************************/
  28
  29 #ifdef HAVE_CONFIG_H
  30 # include "config.h"
  31 #endif
  32 #include <assert.h>
  33
  34 #include <vlc_common.h>
  35 #include <vlc_picture_fifo.h>
  36
  37 /*****************************************************************************
  38  *
  39  *****************************************************************************/
  40 struct picture_fifo_t {
  41     vlc_mutex_t lock;
  42     picture_t   *first;
  43     picture_t   **last_ptr;
  44 };
  45
  46 static void PictureFifoReset(picture_fifo_t *fifo)
  47 {
  48     fifo->first    = NULL;
  49     fifo->last_ptr = &fifo->first;
  50 }
  51 static void PictureFifoPush(picture_fifo_t *fifo, picture_t *picture)
  52 {
  53     assert(!picture->p_next);
  54     *fifo->last_ptr = picture;
  55     fifo->last_ptr  = &picture->p_next;
  56 }
  57 static picture_t *PictureFifoPop(picture_fifo_t *fifo)
  58 {
  59     picture_t *picture = fifo->first;
  60
  61     if (picture) {
  62         fifo->first = picture->p_next;
  63         if (!fifo->first)
  64             fifo->last_ptr = &fifo->first;
  65     }
  66     return picture;
  67 }
  68
  69 picture_fifo_t *picture_fifo_New(void)
  70 {
  71     picture_fifo_t *fifo = malloc(sizeof(*fifo));
  72     if (!fifo)
  73         return NULL;
  74
  75     vlc_mutex_init(&fifo->lock);
  76     PictureFifoReset(fifo);
  77     return fifo;
  78 }
  79
  80 void picture_fifo_Push(picture_fifo_t *fifo, picture_t *picture)
  81 {
  82     vlc_mutex_lock(&fifo->lock);
  83     PictureFifoPush(fifo, picture);
  84     vlc_mutex_unlock(&fifo->lock);
  85 }
  86 picture_t *picture_fifo_Pop(picture_fifo_t *fifo)
  87 {
  88     vlc_mutex_lock(&fifo->lock);
  89     picture_t *picture = PictureFifoPop(fifo);
  90     vlc_mutex_unlock(&fifo->lock);
  91
  92     return picture;
  93 }
  94 picture_t *picture_fifo_Peek(picture_fifo_t *fifo)
  95 {
  96     vlc_mutex_lock(&fifo->lock);
  97     picture_t *picture = fifo->first;
  98     if (picture)
  99         picture_Hold(picture);
 100     vlc_mutex_unlock(&fifo->lock);
 101
 102     return picture;
 103 }
 104 void picture_fifo_Flush(picture_fifo_t *fifo, mtime_t date, bool flush_before)
 105 {
 106     picture_t *picture;
 107
 108     vlc_mutex_lock(&fifo->lock);
 109
 110     picture = fifo->first;
 111     PictureFifoReset(fifo);
 112
 113     picture_fifo_t tmp;
 114     PictureFifoReset(&tmp);
 115
 116     while (picture) {
 117         picture_t *next = picture->p_next;
 118
 119         picture->p_next = NULL;
 120         if (( flush_before && picture->date <= date) ||
 121             (!flush_before && picture->date >= date))
 122             PictureFifoPush(&tmp, picture);
 123         else
 124             PictureFifoPush(fifo, picture);
 125         picture = next;
 126     }
 127     vlc_mutex_unlock(&fifo->lock);
 128
 129     for (;;) {
 130         picture_t *picture = PictureFifoPop(&tmp);
 131         if (!picture)
 132             break;
 133         picture_Release(picture);
 134     }
 135 }
 136 void picture_fifo_OffsetDate(picture_fifo_t *fifo, mtime_t delta)
 137 {
 138     vlc_mutex_lock(&fifo->lock);
 139     for (picture_t *picture = fifo->first; picture != NULL;) {
 140         picture->date += delta;
 141         picture = picture->p_next;
 142     }
 143     vlc_mutex_unlock(&fifo->lock);
 144 }
 145 void picture_fifo_Delete(picture_fifo_t *fifo)
 146 {
 147     picture_fifo_Flush(fifo, INT64_MAX, true);
 148     vlc_mutex_destroy(&fifo->lock);
 149 }
 150