This function can be called without calling snd_pcm_avail_update().
The call to snd_pcm_avail_update() can take some time.
Therefore some developers would not like to call it from a real-time
context (e.g. from JACK client context).
Signed-off-by: Timo Wischer <twischer@de.adit-jv.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This patch fixes the draining behavior of ioplug in the following
ways:
- When no draining ioplug callback is defined, implement the draining
loop using snd_pcm_wait*() and sync with the drain finishes.
This is equivalent with the implementation in the kernel write().
Similarly as in kernel code, for non-blocking mode, it returns
immediately after setting DRAINING state.
- The hw_ptr update function checks the PCM state and stops the stream
if the draining finishes.
- When draining ioplug callback is defined, leave the whole draining
operation to it. The callback is supposed to return -EAGAIN for
non-blocking case, too.
- When an error happens during draining, it drops the stream, for a
safety reason.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
PREPARED should only be set when it is done and it was successfully.
DRAINING should be signalled when starting to drain. There is no need to
check if draining was successfully because it will change to drop (SETUP)
in any case.
Signed-off-by: Timo Wischer <twischer@de.adit-jv.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This function can be called without calling snd_pcm_avail_update().
The call to snd_pcm_avail_update() can take some time.
Therefore some developers would not like to call it from a real-time
context (e.g. from JACK client context).
Signed-off-by: Timo Wischer <twischer@de.adit-jv.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
if requested by the IO plugin
Without this changes an IO plugin is not able to report
that buffer_size frames were read from the buffer.
When the buffer was full this is a valid action and
has not to be handled as an under run.
For example when the hw_ptr will be updated with
hw_ptr += buffer_size
and it is using the buffer_size as wrap around
hw_ptr %= buffer_size
would result in the same value as before the add operation.
Signed-off-by: Timo Wischer <twischer@de.adit-jv.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
In former commits for thread-safe PCM APIs, snd_pcm_ioplug_sw_params() got
0 as its return value, against the original implementation.
This commit fixes it.
Fixes: 54931e5a5455('pcm: Add thread-safety to PCM API')
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Traditionally, many of ALSA library functions are supposed to be
thread-unsafe, and applications are required to take care of thread
safety by themselves. However, people never be careful enough, and
almost all applications fail in this regard.
This patch is an attempt to harden the thread safety in exported PCM
functions in a simplistic way: just wrap some of exported functions
with the pthread mutex of each PCM object. Not all API functions are
wrapped by the mutex since it doesn't make sense. Instead, the
patchset covers only the functions that may be likely called
concurrently. The supposedly thread-safe API functions are marked in
the document.
For achieving the feature, two new fields are added snd_pcm_t when the
option is enabled: thread_safe and lock. The former indicates that
the plugin is thread-safe that doesn't need this workaround and the
latter is the pthread mutex. Currently only hw plugin have
thread_safe=1. So, the most of real-time sensitive apps won't be
influenced by this patchset.
Although the patch covers most of PCM ops, a few snd_pcm_fast_ops are
left without the extra mutex locking: namely, the ones that may have
blocking behavior, i.e. resume, drain, readi, writei, readn and
writen. These are supposed to handle own locking in the callbacks.
Also, if anyone wants to disable this new thread-safe API feature, it
can be still turned off via --disable-thread-safety configure option.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
A few error checks are wrongly performed with logical and (&&) instead
of logical or (||), which condition never met.
Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The current behavior of snd_pcm_rewindable and snd_pcm_forwardable means
that the returned value is only accurate to one period. Or maybe even
meaningless if period interrupts are off. Fetch the up-to-date position
of the hardware pointer, as that's what is wanted by callers.
Signed-off-by: Alexander E. Patrakov <patrakov@gmail.com>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Such negative values can happen when an underrun happens and xrun
detection is disabled. Another situation is if the device updated the
pointer before alsa-lib has a chance to detect the xrun.
The problem is that these negative values could propagate to the
snd_pcm_rewindable return value, where it is specified that negative
returns must be interpreted as error codes and not as negative amount of
samples.
Signed-off-by: Alexander E. Patrakov <patrakov@gmail.com>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Now all PCM plugins do support the proper timestamp type or pass it
over slaves. The internal monotonic flag is dropped and replaced with
tstamp_type in all places.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The function snd_pcm_ioplug_hw_ptr_update() always increased the hw_ptr
by delta, without wrapping it to the boundary. This would lead to
problems when after many hours, the hw_ptr would overflow.
Signed-off-by: Luciano Montanaro <luciano.montanaro@magnetimarelli.com>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Instead of passing ambiguous integer array, define snd_pcm_chmap_t and
snd_pcm_chmap_query_t so that user can understand more easily which
element is for what.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
When snd_pcm_start() is called in the invalid state, it should return
-EBADFD. But ioplug plugin returns -EAGAIN. Let's fix it.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This ensures they are emitted in .data.rel.ro rather than .data.rel,
which should make a nice difference when using prelink.
Signed-off-by: Diego E. 'Flameeyes' Pettenò <flameeyes@gmail.com>
By doing this we move them from the .data section to .rodata setion,
or from .data.rel to .data.rel.ro.
The .rodata section is mapped directly from the on-disk file, which is
always a save, while .data.rel.ro is mapped directly when using
prelink, which is a save in a lot of cases.
Signed-off-by: Diego E. 'Flameeyes' Pettenò <flameeyes@gmail.com>
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.
Some io plug-ins might want to adjust the reported delay value and not
strictly follow the current buffer usage (that's why we have two calls
after all).
Allow them to specify a delay() callback and use the previous behaviour
if they don't.
Signed-off-by: Pierre Ossman <ossman@cendio.se>
- Added protocl version check. The caller of snd_pcm_{io|ext}plug_create()
must fill version field with SND_PCM_{IO|EXT}PLUG_VERSION beforehand.
- Added poll_descriptors and poll_descriptors_count callbacks for ioplug.
