/*
- * Copyright (C) 2009-2014 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2009-2014 Andre Noll <maan@tuebingen.mpg.de>
*
* Licensed under the GPL v2. For licencing details see COPYING.
*/
#include <regex.h>
#include <sys/ioctl.h>
-#include <fcntl.h>
#include <sys/soundcard.h>
#include "para.h"
int bytes_per_frame;
};
+/*
+ * We keep one bit of static storage to make sure only one instance of the oss
+ * writer is running at any given time.
+ */
+static bool sound_device_busy;
+
+static bool sound_device_is_busy(void)
+{
+ return sound_device_busy;
+}
+
+static void set_sound_device_busy(void)
+{
+ assert(!sound_device_busy);
+ sound_device_busy = true;
+}
+
+static void set_sound_device_idle(void)
+{
+ assert(sound_device_busy);
+ sound_device_busy = false;
+}
+
static int get_oss_format(enum sample_format sf)
{
switch (sf) {
}
}
-static void oss_pre_select(struct sched *s, struct task *t)
+static void oss_pre_select(struct sched *s, void *context)
{
- struct writer_node *wn = container_of(t, struct writer_node, task);
+ struct writer_node *wn = context;
struct private_oss_write_data *powd = wn->private_data;
int ret = btr_node_status(wn->btrn, wn->min_iqs, BTR_NT_LEAF);
- if (ret == 0)
+ if (ret == 0 || (sound_device_is_busy() && !powd))
return;
if (ret < 0 || !powd)
return sched_min_delay(s);
return;
close(powd->fd);
free(powd);
+ set_sound_device_idle();
}
/*
* Set sampling rate
*
* If we request a higher sampling rate than is supported by the
- * device, the the highest possible speed is automatically used. The
+ * device, the highest possible speed is automatically used. The
* value actually used is returned as the new value of the argument.
*/
rate = sample_rate;
return ret;
}
-static int oss_post_select(__a_unused struct sched *s,
- struct task *t)
+static int oss_post_select(__a_unused struct sched *s, void *context)
{
- struct writer_node *wn = container_of(t, struct writer_node, task);
+ struct writer_node *wn = context;
struct private_oss_write_data *powd = wn->private_data;
struct btr_node *btrn = wn->btrn;
size_t frames, bytes;
int ret;
char *data;
+ audio_buf_info abi;
- ret = task_get_notification(t);
+ ret = task_get_notification(wn->task);
if (ret < 0)
goto out;
ret = btr_node_status(btrn, wn->min_iqs, BTR_NT_LEAF);
goto out;
if (!powd) {
int32_t rate, ch, format;
+
+ if (sound_device_is_busy())
+ return 0;
get_btr_sample_rate(btrn, &rate);
get_btr_channels(btrn, &ch);
get_btr_sample_format(btrn, &format);
ret = oss_init(wn, rate, ch, format);
if (ret < 0)
goto out;
+ set_sound_device_busy();
return 0;
}
btr_merge(btrn, wn->min_iqs);
ret = 0;
if (!FD_ISSET(powd->fd, &s->wfds))
goto out;
+ /* get maximal number of bytes that can be written */
+ ret = ioctl(powd->fd, SNDCTL_DSP_GETOSPACE, &abi);
+ if (ret >= 0) {
+ size_t max_frames = abi.bytes / powd->bytes_per_frame;
+ if (max_frames == 0)
+ goto out;
+ /* cap number of frames to avoid sound artefacts */
+ frames = PARA_MIN(frames, max_frames);
+ }
ret = xwrite(powd->fd, data, frames * powd->bytes_per_frame);
if (ret < 0)
goto out;