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Timo Wischer b420056604 pcm: interval: Interpret (x x+1] correctly and return x+1
Without this change an interval of (x x+1] will be interpreted as an
empty interval but the right value would be x+1.
This leads to a failing snd_pcm_hw_params() call which returns -EINVAL.

An example issue log is given in the following:
snd_pcm_hw_params failed with err -22 (Invalid argument)
ACCESS: MMAP_NONINTERLEAVED
FORMAT: S16_LE
SUBFORMAT: STD
SAMPLE_BITS: 16
FRAME_BITS: 16
CHANNELS: 1
RATE: 16000
PERIOD_TIME: (15999 16000]
PERIOD_SIZE: (255 256]
PERIOD_BYTES: (510 512]
PERIODS: [2 3)
BUFFER_TIME: 32000
BUFFER_SIZE: 512
BUFFER_BYTES: 1024

In case of (x x+1) we have to interpret it anyway as a single value of x to
compensate rounding issues.
For example the period size will result in an interval of (352 353) when
the period time is 16ms and the sample rate 22050 Hz
(16ms * 22,05 kHz = 352,8 frames). But 352 has to be chosen to allow a
buffer size of 705 (32ms * 22,05 kHz = 705,6 frames) which has to be >= 2x
period size to avoid Xruns. The buffer size will not end up with an
interval of (705 706) simular to the period size because
snd_pcm_rate_hw_refine_cchange() calls snd_interval_floor() for the buffer
size. Therefore this value will be interpreted as an integer interval
instead of a real interval further on.

This issue seems to exist since the change of 9bb985c38 ("pcm:
snd_interval_refine_first/last: exclude value only if also excluded
before")

Signed-off-by: Timo Wischer <twischer@de.adit-jv.com>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
2018-10-24 12:07:33 +02:00
alsalisp Change FSF address (Franklin Street) 2017-11-14 14:29:26 +01:00
aserver a set of fixes to reduce gcc warnings 2018-03-27 15:16:41 +02:00
doc doxygen: Suppress timestamp 2016-06-23 16:29:07 +02:00
include ioplug: Fix comment in struct snd_pcm_ioplug 2018-10-02 17:56:51 +02:00
m4 Add the attributes.m4 macro file from xine/lscube. 2008-11-21 13:04:19 +01:00
modules modules: smixer_python - add support for python3 2018-03-27 14:51:39 +02:00
src pcm: interval: Interpret (x x+1] correctly and return x+1 2018-10-24 12:07:33 +02:00
test test/audio_time: remove unused variables 2018-10-24 12:07:33 +02:00
utils autotools: update style 2014-02-26 08:16:22 +01:00
.gitignore Add pcm-multi-thread to .gitignore 2016-07-07 16:30:54 +02:00
acinclude.m4 fixed for the recent autoconf. 2004-01-26 15:52:17 +00:00
ChangeLog * update to libtool 1.3.3 1999-07-22 12:18:42 +00:00
configure.ac Release v1.1.7 2018-10-16 10:08:35 +02:00
COPYING Change FSF address (Franklin Street) 2017-11-14 14:29:26 +01:00
gitcompile a set of fixes to reduce gcc warnings 2018-03-27 15:16:41 +02:00
INSTALL pcm: Add thread-safety to PCM API 2016-07-11 15:25:30 +02:00
Makefile.am autotools: update style 2014-02-26 08:16:22 +01:00
MEMORY-LEAK Initial version 2003-02-04 14:56:07 +00:00
NOTES Change assert condition in error message handler 2007-10-24 12:53:08 +02:00
TODO Added snd_config_load_override(). 2002-01-09 21:28:15 +00:00