merge 'lennart' branch back into trunk.

git-svn-id: file:///home/lennart/svn/public/pulseaudio/trunk@1971 fefdeb5f-60dc-0310-8127-8f9354f1896f

src/pulsecore/asyncq.h

@@ -0,0 +1,56 @@
+#ifndef foopulseasyncqhfoo
+#define foopulseasyncqhfoo
+
+/* $Id$ */
+
+/***
+  This file is part of PulseAudio.
+
+  Copyright 2004-2006 Lennart Poettering
+
+  PulseAudio is free software; you can redistribute it and/or modify
+  it under the terms of the GNU Lesser General Public License as
+  published by the Free Software Foundation; either version 2.1 of the
+  License, or (at your option) any later version.
+
+  PulseAudio is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with PulseAudio; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+  USA.
+***/
+
+#include <sys/types.h>
+#include <pulse/def.h>
+
+/* A simple, asynchronous, lock-free (if requested also wait-free)
+ * queue. Not multiple-reader/multiple-writer safe. If that is
+ * required both sides can be protected by a mutex each. --- Which is
+ * not a bad thing in most cases, since this queue is intended for
+ * communication between a normal thread and a single real-time
+ * thread. Only the real-time side needs to be lock-free/wait-free.
+ *
+ * If the queue is full and another entry shall be pushed, or when the
+ * queue is empty and another entry shall be popped and the "wait"
+ * argument is non-zero, the queue will block on a UNIX FIFO object --
+ * that will probably require locking on the kernel side -- which
+ * however is probably not problematic, because we do it only on
+ * starvation or overload in which case we have to block anyway.  */
+
+typedef struct pa_asyncq pa_asyncq;
+
+pa_asyncq* pa_asyncq_new(unsigned size);
+void pa_asyncq_free(pa_asyncq* q, pa_free_cb_t free_cb);
+
+void* pa_asyncq_pop(pa_asyncq *q, int wait);
+int pa_asyncq_push(pa_asyncq *q, void *p, int wait);
+
+int pa_asyncq_get_fd(pa_asyncq *q);
+int pa_asyncq_before_poll(pa_asyncq *a);
+void pa_asyncq_after_poll(pa_asyncq *a);
+
+#endif