code.delx.au - pulseaudio/blob - polyp/memblockq.h

   1 #ifndef foomemblockqhfoo
   2 #define foomemblockqhfoo
   3
   4 /* $Id$ */
   5
   6 /***
   7   This file is part of polypaudio.
   8
   9   polypaudio is free software; you can redistribute it and/or modify
  10   it under the terms of the GNU General Public License as published
  11   by the Free Software Foundation; either version 2 of the License,
  12   or (at your option) any later version.
  13
  14   polypaudio is distributed in the hope that it will be useful, but
  15   WITHOUT ANY WARRANTY; without even the implied warranty of
  16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  17   General Public License for more details.
  18
  19   You should have received a copy of the GNU General Public License
  20   along with polypaudio; if not, write to the Free Software
  21   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  22   USA.
  23 ***/
  24
  25 #include <sys/types.h>
  26
  27 #include "memblock.h"
  28 #include "memchunk.h"
  29
  30 struct pa_memblockq;
  31
  32 /* Parameters:
  33    - maxlength: maximum length of queue. If more data is pushed into the queue, data from the front is dropped
  34    - length:    the target length of the queue.
  35    - base:      a base value for all metrics. Only multiples of this value are popped from the queue
  36    - prebuf:    before passing the first byte out, make sure that enough bytes are in the queue
  37    - minreq:    pa_memblockq_missing() will only return values greater than this value
  38 */
  39 struct pa_memblockq* pa_memblockq_new(size_t maxlength,
  40                                       size_t tlength,
  41                                       size_t base,
  42                                       size_t prebuf,
  43                                       size_t minreq);
  44 void pa_memblockq_free(struct pa_memblockq*bq);
  45
  46 /* Push a new memory chunk into the queue. Optionally specify a value for future cancellation. This is currently not implemented, however! */
  47 void pa_memblockq_push(struct pa_memblockq* bq, const struct pa_memchunk *chunk, size_t delta);
  48
  49 /* Same as pa_memblockq_push(), however chunks are filtered through a mcalign object, and thus aligned to multiples of base */
  50 void pa_memblockq_push_align(struct pa_memblockq* bq, const struct pa_memchunk *chunk, size_t delta);
  51
  52 /* Return a copy of the next memory chunk in the queue. It is not removed from the queue */
  53 int pa_memblockq_peek(struct pa_memblockq* bq, struct pa_memchunk *chunk);
  54
  55 /* Drop the specified bytes from the queue */
  56 void pa_memblockq_drop(struct pa_memblockq *bq, size_t length);
  57
  58 /* Shorten the pa_memblockq to the specified length by dropping data at the end of the queue */
  59 void pa_memblockq_shorten(struct pa_memblockq *bq, size_t length);
  60
  61 /* Empty the pa_memblockq */
  62 void pa_memblockq_empty(struct pa_memblockq *bq);
  63
  64 /* Test if the pa_memblockq is currently readable, that is, more data than base */
  65 int pa_memblockq_is_readable(struct pa_memblockq *bq);
  66
  67 /* Test if the pa_memblockq is currently writable for the specified amount of bytes */
  68 int pa_memblockq_is_writable(struct pa_memblockq *bq, size_t length);
  69
  70 /* The time memory chunks stay in the queue until they are removed completely in usecs */
  71 uint32_t pa_memblockq_get_delay(struct pa_memblockq *bq);
  72
  73 /* Return the length of the queue in bytes */
  74 uint32_t pa_memblockq_get_length(struct pa_memblockq *bq);
  75
  76 /* Return how many bytes are missing in queue to the specified fill amount */
  77 uint32_t pa_memblockq_missing(struct pa_memblockq *bq);
  78
  79
  80 uint32_t pa_memblockq_get_minreq(struct pa_memblockq *bq);
  81
  82 #endif