src/pulse/operation.c

   1 /***
   2   This file is part of PulseAudio.
   3
   4   Copyright 2004-2006 Lennart Poettering
   5
   6   PulseAudio is free software; you can redistribute it and/or modify
   7   it under the terms of the GNU Lesser General Public License as published
   8   by the Free Software Foundation; either version 2.1 of the License,
   9   or (at your option) any later version.
  10
  11   PulseAudio is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with PulseAudio; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <pulse/xmalloc.h>
  27 #include <pulsecore/macro.h>
  28 #include <pulsecore/flist.h>
  29
  30 #include "internal.h"
  31 #include "operation.h"
  32
  33 PA_STATIC_FLIST_DECLARE(operations, 0, pa_xfree);
  34
  35 pa_operation *pa_operation_new(pa_context *c, pa_stream *s, pa_operation_cb_t cb, void *userdata) {
  36     pa_operation *o;
  37     pa_assert(c);
  38
  39     if (!(o = pa_flist_pop(PA_STATIC_FLIST_GET(operations))))
  40         o = pa_xnew(pa_operation, 1);
  41
  42     PA_REFCNT_INIT(o);
  43     o->context = c;
  44     o->stream = s;
  45     o->private = NULL;
  46
  47     o->state = PA_OPERATION_RUNNING;
  48     o->callback = cb;
  49     o->userdata = userdata;
  50
  51     /* Refcounting is strictly one-way: from the "bigger" to the "smaller" object. */
  52     PA_LLIST_PREPEND(pa_operation, c->operations, o);
  53     pa_operation_ref(o);
  54
  55     return o;
  56 }
  57
  58 pa_operation *pa_operation_ref(pa_operation *o) {
  59     pa_assert(o);
  60     pa_assert(PA_REFCNT_VALUE(o) >= 1);
  61
  62     PA_REFCNT_INC(o);
  63     return o;
  64 }
  65
  66 void pa_operation_unref(pa_operation *o) {
  67     pa_assert(o);
  68     pa_assert(PA_REFCNT_VALUE(o) >= 1);
  69
  70     if (PA_REFCNT_DEC(o) <= 0) {
  71         pa_assert(!o->context);
  72         pa_assert(!o->stream);
  73
  74         if (pa_flist_push(PA_STATIC_FLIST_GET(operations), o) < 0)
  75             pa_xfree(o);
  76     }
  77 }
  78
  79 static void operation_unlink(pa_operation *o) {
  80     pa_assert(o);
  81
  82     if (o->context) {
  83         pa_assert(PA_REFCNT_VALUE(o) >= 2);
  84
  85         PA_LLIST_REMOVE(pa_operation, o->context->operations, o);
  86         pa_operation_unref(o);
  87
  88         o->context = NULL;
  89     }
  90
  91     o->stream = NULL;
  92     o->callback = NULL;
  93     o->userdata = NULL;
  94 }
  95
  96 static void operation_set_state(pa_operation *o, pa_operation_state_t st) {
  97     pa_assert(o);
  98     pa_assert(PA_REFCNT_VALUE(o) >= 1);
  99
 100     if (st == o->state)
 101         return;
 102
 103     pa_operation_ref(o);
 104
 105     o->state = st;
 106
 107     if ((o->state == PA_OPERATION_DONE) || (o->state == PA_OPERATION_CANCELED))
 108         operation_unlink(o);
 109
 110     pa_operation_unref(o);
 111 }
 112
 113 void pa_operation_cancel(pa_operation *o) {
 114     pa_assert(o);
 115     pa_assert(PA_REFCNT_VALUE(o) >= 1);
 116
 117     operation_set_state(o, PA_OPERATION_CANCELED);
 118 }
 119
 120 void pa_operation_done(pa_operation *o) {
 121     pa_assert(o);
 122     pa_assert(PA_REFCNT_VALUE(o) >= 1);
 123
 124     operation_set_state(o, PA_OPERATION_DONE);
 125 }
 126
 127 pa_operation_state_t pa_operation_get_state(pa_operation *o) {
 128     pa_assert(o);
 129     pa_assert(PA_REFCNT_VALUE(o) >= 1);
 130
 131     return o->state;
 132 }