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Author SHA1 Message Date
Takashi Sakamoto
b83a8cd3be axfer: add a parser for command-line options
In aplay, many command-line options are supported. Some of them have
dependency or conflicts. Furthemore, some of them are just for
runtime configuration of alsa-lib(libasound), and some options can
be used by several xfer backends commonly; e.g. options for file name,
sample format and sampling rate.

This commit adds a parser for the common options below.
 * --help (-h)
  * Just output 'help' string (not written yet).
 * --verbose (-v)
  * For verbose output, including information about xfer, mapper and
    container.
 * --format (-f): string. format literals or one of ['cd'|'cdr'|'dat']
  * For sample format supported by ALSA PCM interface. Special format
    can be used. For playback, this is auto-detected according to actual
    file format.
 * --channels (-c)
  * For the number of samples included in one data frame. For playback,
    this is auto-detected according to actual file format, except for
    'raw' format. This option can conflict to above format option.
 * --rate (-r)
  * For the number of data frames transferred in one second. For playback,
    this is auto-detected according to actual file format, except for
    'raw' format. This option can conflict to format option above.
 * --file-type (-f): string. one of ['wav'|'au'|'voc'|'raw']
  * For format of files of given paths. For playback, this is optional
    because the format is auto-detected. For capture, this is optional too
    because the format is decided according to suffix of given path.
    Anyway, this option is used for cases to fail to detect or decide.
 * --separate-channels (-I)
  * When using several files as source or destination for transmission
    of data frame, this option can be used with several file paths.

When '--separate-channels' option is used, users can give several file
paths to source/destination of data transmission, else they can give single
file path for the purpose. When multiple files are handled by this option,
for playback, data frames in first channel is used to construct buffer for
data transmission with multi channel. For capture, data frames in each
channel of buffer are written to each of given path. Furthermore, when a
single path is given for capture, file paths are auto-generated according
to available number of channels. For example, 'name.wav' is given for
2 channels capture, 'name-0.wav' and 'name-1.wav' are generated. In a
case of no suffix, 'name-0' and 'name-1' are generated.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-11-13 12:04:30 +01:00
Takashi Sakamoto
a452b98235 axfer: add an entry point for this command
This commit adds a new command, 'axfer' ('ALSA transfer'), to transfer data
frames described in asound.h. This command is intended to replace current
aplay. The most of features and command line parameters come from aplay as
much as possible, while it has more better feature and code to maintain.

This commit adds an entry point for this command. Current option system of
aplay is still available, while this command has a sub-command system like
commands in iproute2.

Currently, two sub-commands are supported; 'list' and 'transfer'. The
'list' sub-command has the same effect as '-l' and '-L' options of aplay.
The 'transfer' sub-command has the same effect as the main feature of
aplay. For the sub-command system, an option for stream direction is
required; '-P' for playback and '-C' for capture. If you create symbolic
links to this binary for aplay/arecord, please execute:
$ ln -s axfer aplay
$ ln -s axfer arecord

Actual code for each sub-command will be implemented in later commits.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-11-13 12:04:19 +01:00