code.delx.au - pulseaudio/blob - src/pulsecore/fdsem.h

   1 #ifndef foopulsefdsemhfoo
   2 #define foopulsefdsemhfoo
   3
   4 /***
   5   This file is part of PulseAudio.
   6
   7   Copyright 2004-2006 Lennart Poettering
   8
   9   PulseAudio is free software; you can redistribute it and/or modify
  10   it under the terms of the GNU Lesser General Public License as
  11   published by the Free Software Foundation; either version 2.1 of the
  12   License, or (at your option) any later version.
  13
  14   PulseAudio 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   Lesser General Public License for more details.
  18
  19   You should have received a copy of the GNU Lesser General Public
  20   License along with PulseAudio; 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 /* A simple, asynchronous semaphore which uses fds for sleeping. In
  28  * the best case all functions are lock-free unless sleeping is
  29  * required.  */
  30
  31 typedef struct pa_fdsem pa_fdsem;
  32
  33 typedef struct pa_fdsem_data {
  34     pa_atomic_t waiting;
  35     pa_atomic_t signalled;
  36     pa_atomic_t in_pipe;
  37 } pa_fdsem_data;
  38
  39 pa_fdsem *pa_fdsem_new(void);
  40 pa_fdsem *pa_fdsem_open_shm(pa_fdsem_data *data, int event_fd);
  41 pa_fdsem *pa_fdsem_new_shm(pa_fdsem_data *data, int* event_fd);
  42 void pa_fdsem_free(pa_fdsem *f);
  43
  44 void pa_fdsem_post(pa_fdsem *f);
  45 void pa_fdsem_wait(pa_fdsem *f);
  46 int pa_fdsem_try(pa_fdsem *f);
  47
  48 int pa_fdsem_get(pa_fdsem *f);
  49
  50 int pa_fdsem_before_poll(pa_fdsem *f);
  51 int pa_fdsem_after_poll(pa_fdsem *f);
  52
  53 #endif