Some broken applications like Audacious don't set any timing parameters.
While the alsa-lib behaviour is to select the smallest period size and
biggest buffer size, the result is the generation of thousands
interrupts per second.
The default value in alsa.conf is 5000usec.
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
The documentation for the latency parameter of pcm_set_params() says
that the value 0 uses an optimal value. This is wrong, as there is no
special handling for 0, and the result will be a buffer of minimal size.
Therefore, remove that incorrect statement.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
The revents parameter is ambiguously defined whether it's a pointer
to a single event or an arary.
This patch defines the behavior of revents more strictly (in the
function description): it's a pointer of a single event.
Also fixed snd_pcm_wait_nocheck() to follow that rule.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Use "const char *const []" as type for string arrays, or convert to
"const char [][x]" when it makes sense.
Signed-off-by: Diego E. 'Flameeyes' Pettenò <flameeyes@gmail.com>
As proposed in http://mailman.alsa-project.org/pipermail/alsa-devel/2008-June/008558.html
the snd_pcm_avail() and snd_pcm_avail_delay() functions are now available
to get accurate stream position in a straight way. The snd_pcm_avail_delay()
function was added to ensure full sync between avail and delay values. It's
actually implemented using delay() + avail_update() calls but it might be
changed in future.
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
snd_pcm_delay() is for synchronization purposes, it returns the overall latency
of the stream, not just the latency induced by the hardware playback buffer.
The documentation is a bit misleading about this fact, and some people already
misunderstood it. So let's reword this to make the explanation clearer and
explicit.
This is a result of the discussions of the thread this mail belongs to:
http://mailman.alsa-project.org/pipermail/alsa-devel/2008-June/008456.html
From: Lennart Poettering <mznyfn@0pointer.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
The PCM name isn't set properly on empty and asym plugins due to its call
of snd_pcm_open_slave(). Now a new function snd_pcm_open_named_slave()
is created and make snd_pcm_open_slave() an inline function calling the
new one with name=NULL.
Added --with-configdir and --with-plugindir options to configure
which specify the directories for config files and plugin objects
respectively. The default paths when these options are not
specified are unchanged.
Instead of link_fd, more generic callback link_slaves is introduced.
This is called for linking the slave streams as the source to the
given master stream.
- add long card name to device description
- create empty PCM plugin to allow right hint description parsing
- reorder devices in alsa.conf
- make namehint more configurable (using default.namehint.showall switch)
- add two levels basic and exteded for hints to default configuration files
- do not show direct device aliases
- removed all known memory leaks
- add snd_device_name_hint() and snd_device_name_free_hint() functions
- add snd_ctl_iface_conf_name() functions
- do not accept parameters for the plugin definition without @args section
- add defaults.pcm.dmix.card/device and dsnoop.card/device definitions
- add hints for HDA-Intel.conf, pcm/dmix.conf, pcm/dsnoop.conf and alsa.conf
- add test/namehint test utility
- doxygen related cleanups
Fix the PCM auto-start conditions
- The capture stream should be started the PCM anyway before reads
- Fixed the endless poll() when the written size doesn't fit to the
buffer size due to lack of auto-start
Remove several memory leaks by not aborting prematurely from a
snd_xxx_close() function when some operation fails.
This can happen when a USB device was unplugged.
