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Added description of shm, null and rate plugins

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This commit is contained in:
Jaroslav Kysela 2002-01-22 14:27:25 +00:00
parent f14063a251
commit 2cc79806a2
6 changed files with 216 additions and 13 deletions
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3
doc/doxygen.cfg
View file

@ -38,6 +38,8 @@ INPUT = index.doxygen \
../src/pcm/pcm_mmap.c \
../src/pcm/pcm_plugin.c \
../src/pcm/pcm_hw.c \
../src/pcm/pcm_shm.c \
../src/pcm/pcm_null.c \
../src/pcm/pcm_copy.c \
../src/pcm/pcm_linear.c \
../src/pcm/pcm_lfloat.c \
@ -45,6 +47,7 @@ INPUT = index.doxygen \
../src/pcm/pcm_alaw.c \
../src/pcm/pcm_adpcm.c \
../src/pcm/pcm_route.c \
../src/pcm/pcm_rate.c \
../src/pcm/pcm_plug.c \
../src/pcm/pcm_file.c \
../src/pcm/pcm_multi.c \

2
src/pcm/pcm_hw.c
View file

@ -827,7 +827,7 @@ int snd_pcm_hw_open(snd_pcm_t **pcmp, const char *name,
This plugin communicates directly with the ALSA kernel driver. It is a raw
communication without any conversions. The emulation of mmap access can be
optionally enabled, but expect a worse latency in the case.
optionally enabled, but expect worse latency in the case.
\code
pcm.name {

15
src/pcm/pcm_ladspa.c
View file

@ -1185,6 +1185,11 @@ This plugin allows to apply a set of LADPSA plugins.
The input and output format is always #SND_PCM_FORMAT_FLOAT (note: this type
can be either little or big-endian depending on architecture).
The policy duplicate means that there must be only one binding definition for
channel zero. This definition is automatically duplicated for all channels.
Instances of LADSPA plugins are created dynamically.
\code
pcm.name {
type ladspa # ALSA<->LADSPA PCM
@ -1195,15 +1200,15 @@ pcm.name {
# or
pcm { } # Slave PCM definition
}
path STR # Path (directory) with LADSPA plugins
[path STR] # Path (directory) with LADSPA plugins
plugins | # Definition for both directions
playback_plugins | # Definition for playback direction
capture_plugins { # Definition for capture direction
N { # Configuration for LADPSA plugin N
id INT # LADSPA plugin ID (for example 1043)
label STR # LADSPA plugin label (for example 'delay_5s')
filename STR # Full filename of .so library with LADSPA plugin code
policy STR # Policy can be 'none' or 'duplicate'
[id INT] # LADSPA plugin ID (for example 1043)
[label STR] # LADSPA plugin label (for example 'delay_5s')
[filename STR] # Full filename of .so library with LADSPA plugin code
[policy STR] # Policy can be 'none' or 'duplicate'
input | output {
bindings {
C INT or STR # C - channel, INT - audio port index, STR - audio port name

64
src/pcm/pcm_null.c
View file

@ -1,3 +1,10 @@
/**
* \file pcm/pcm_null.c
* \ingroup PCM_Plugins
* \brief PCM Null Plugin Interface
* \author Abramo Bagnara <abramo@alsa-project.org>
* \date 2000-2001
*/
/*
* PCM - Null plugin
* Copyright (c) 2000 by Abramo Bagnara <abramo@alsa-project.org>
@ -30,6 +37,7 @@
const char *_snd_module_pcm_null = "";
#endif
#ifndef DOC_HIDDEN
typedef struct {
snd_timestamp_t trigger_tstamp;
snd_pcm_state_t state;
@ -38,6 +46,7 @@ typedef struct {
snd_pcm_uframes_t hw_ptr;
int poll_fd;
} snd_pcm_null_t;
#endif
static int snd_pcm_null_close(snd_pcm_t *pcm)
{
@ -295,7 +304,7 @@ static void snd_pcm_null_dump(snd_pcm_t *pcm, snd_output_t *out)
}
}
snd_pcm_ops_t snd_pcm_null_ops = {
static snd_pcm_ops_t snd_pcm_null_ops = {
close: snd_pcm_null_close,
info: snd_pcm_null_info,
hw_refine: snd_pcm_null_hw_refine,
@ -310,7 +319,7 @@ snd_pcm_ops_t snd_pcm_null_ops = {
munmap: snd_pcm_null_munmap,
};
snd_pcm_fast_ops_t snd_pcm_null_fast_ops = {
static snd_pcm_fast_ops_t snd_pcm_null_fast_ops = {
status: snd_pcm_null_status,
state: snd_pcm_null_state,
delay: snd_pcm_null_delay,
@ -330,6 +339,17 @@ snd_pcm_fast_ops_t snd_pcm_null_fast_ops = {
mmap_commit: snd_pcm_null_mmap_commit,
};
/**
* \brief Creates a new null PCM
* \param pcmp Returns created PCM handle
* \param name Name of PCM
* \param stream Stream type
* \param mode Stream mode
* \retval zero on success otherwise a negative error code
* \warning Using of this function might be dangerous in the sense
* of compatibility reasons. The prototype might be freely
* changed in future.
*/
int snd_pcm_null_open(snd_pcm_t **pcmp, const char *name, snd_pcm_stream_t stream, int mode)
{
snd_pcm_t *pcm;
@ -375,6 +395,44 @@ int snd_pcm_null_open(snd_pcm_t **pcmp, const char *name, snd_pcm_stream_t strea
return 0;
}
/*! \page pcm_plugins
\section pcm_plugins_null Plugin: Null
This plugin discards contents of a PCM stream or creates a stream with zero
samples.
Note: This implementation uses devices /dev/null (playback, must be writeable)
and /dev/full (capture, must be readable).
\code
pcm.name {
type null # Null PCM
}
\endcode
\subsection pcm_plugins_null_funcref Function reference
<UL>
<LI>snd_pcm_null_open()
<LI>_snd_pcm_null_open()
</UL>
*/
/**
* \brief Creates a new Null PCM
* \param pcmp Returns created PCM handle
* \param name Name of PCM
* \param root Root configuration node
* \param conf Configuration node with Null PCM description
* \param stream Stream type
* \param mode Stream mode
* \retval zero on success otherwise a negative error code
* \warning Using of this function might be dangerous in the sense
* of compatibility reasons. The prototype might be freely
* changed in future.
*/
int _snd_pcm_null_open(snd_pcm_t **pcmp, const char *name,
snd_config_t *conf,
snd_pcm_stream_t stream, int mode)
@ -392,4 +450,6 @@ int _snd_pcm_null_open(snd_pcm_t **pcmp, const char *name,
}
return snd_pcm_null_open(pcmp, name, stream, mode);
}
#ifndef DOC_HIDDEN
SND_DLSYM_BUILD_VERSION(_snd_pcm_null_open, SND_PCM_DLSYM_VERSION);
#endif

70
src/pcm/pcm_rate.c
View file

@ -1,3 +1,10 @@
/**
* \file pcm/pcm_rate.c
* \ingroup PCM_Plugins
* \brief PCM Rate Plugin Interface
* \author Abramo Bagnara <abramo@alsa-project.org>
* \date 2000-2001
*/
/*
* PCM - Rate conversion
* Copyright (c) 2000 by Abramo Bagnara <abramo@alsa-project.org>
@ -29,6 +36,8 @@
const char *_snd_module_pcm_rate = "";
#endif
#ifndef DOC_HIDDEN
#define DIV (1<<16)
typedef struct {
@ -212,6 +221,8 @@ static snd_pcm_uframes_t snd_pcm_rate_shrink(const snd_pcm_channel_area_t *dst_a
return src_frames1;
}
#endif /* DOC_HIDDEN */
static int snd_pcm_rate_hw_refine_cprepare(snd_pcm_t *pcm ATTRIBUTE_UNUSED, snd_pcm_hw_params_t *params)
{
int err;
@ -479,7 +490,7 @@ static void snd_pcm_rate_dump(snd_pcm_t *pcm, snd_output_t *out)
snd_pcm_dump(rate->plug.slave, out);
}
snd_pcm_ops_t snd_pcm_rate_ops = {
static snd_pcm_ops_t snd_pcm_rate_ops = {
close: snd_pcm_plugin_close,
info: snd_pcm_plugin_info,
hw_refine: snd_pcm_rate_hw_refine,
@ -494,6 +505,20 @@ snd_pcm_ops_t snd_pcm_rate_ops = {
munmap: snd_pcm_plugin_munmap,
};
/**
* \brief Creates a new rate PCM
* \param pcmp Returns created PCM handle
* \param name Name of PCM
* \param sformat Slave format
* \param srate Slave rate
* \param slave Slave PCM handle
* \param close_slave When set, the slave PCM handle is closed with copy PCM
* \retval zero on success otherwise a negative error code
* \warning Using of this function might be dangerous in the sense
* of compatibility reasons. The prototype might be freely
* changed in future.
*/
int snd_pcm_rate_open(snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sformat, unsigned int srate, snd_pcm_t *slave, int close_slave)
{
snd_pcm_t *pcm;
@ -533,6 +558,47 @@ int snd_pcm_rate_open(snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sform
return 0;
}
/*! \page pcm_plugins
\section pcm_plugins_rate Plugin: Rate
This plugin converts a stream rate. The input and output formats must be linear.
\code
pcm.name {
type rate # Rate PCM
slave STR # Slave name
# or
slave { # Slave definition
pcm STR # Slave PCM name
# or
pcm { } # Slave PCM definition
}
}
\endcode
\subsection pcm_plugins_rate_funcref Function reference
<UL>
<LI>snd_pcm_rate_open()
<LI>_snd_pcm_rate_open()
</UL>
*/
/**
* \brief Creates a new rate PCM
* \param pcmp Returns created PCM handle
* \param name Name of PCM
* \param root Root configuration node
* \param conf Configuration node with rate PCM description
* \param stream Stream type
* \param mode Stream mode
* \retval zero on success otherwise a negative error code
* \warning Using of this function might be dangerous in the sense
* of compatibility reasons. The prototype might be freely
* changed in future.
*/
int _snd_pcm_rate_open(snd_pcm_t **pcmp, const char *name,
snd_config_t *root, snd_config_t *conf,
snd_pcm_stream_t stream, int mode)
@ -582,4 +648,6 @@ int _snd_pcm_rate_open(snd_pcm_t **pcmp, const char *name,
snd_pcm_close(spcm);
return err;
}
#ifndef DOC_HIDDEN
SND_DLSYM_BUILD_VERSION(_snd_pcm_rate_open, SND_PCM_DLSYM_VERSION);
#endif

75
src/pcm/pcm_shm.c
View file

@ -1,5 +1,12 @@
/**
* \file pcm/pcm_shm.c
* \ingroup PCM_Plugins
* \brief PCM Shared Memory Plugin Interface
* \author Abramo Bagnara <abramo@alsa-project.org>
* \date 2000-2001
*/
/*
* PCM - SHM Client
* PCM - Shared Memory Client
* Copyright (c) 2000 by Abramo Bagnara <abramo@alsa-project.org>
*
*
@ -43,11 +50,14 @@
const char *_snd_module_pcm_shm = "";
#endif
#ifndef DOC_HIDDEN
typedef struct {
int socket;
volatile snd_pcm_shm_ctrl_t *ctrl;
} snd_pcm_shm_t;
#endif
#ifndef DOC_HIDDEN
int receive_fd(int sock, void *data, size_t len, int *fd)
{
int ret;
@ -81,6 +91,7 @@ int receive_fd(int sock, void *data, size_t len, int *fd)
*fd = *fds;
return ret;
}
#endif
static int snd_pcm_shm_action(snd_pcm_t *pcm)
{
@ -493,7 +504,7 @@ static void snd_pcm_shm_dump(snd_pcm_t *pcm, snd_output_t *out)
}
}
snd_pcm_ops_t snd_pcm_shm_ops = {
static snd_pcm_ops_t snd_pcm_shm_ops = {
close: snd_pcm_shm_close,
info: snd_pcm_shm_info,
hw_refine: snd_pcm_shm_hw_refine,
@ -508,7 +519,7 @@ snd_pcm_ops_t snd_pcm_shm_ops = {
munmap: snd_pcm_shm_munmap,
};
snd_pcm_fast_ops_t snd_pcm_shm_fast_ops = {
static snd_pcm_fast_ops_t snd_pcm_shm_fast_ops = {
status: snd_pcm_shm_status,
state: snd_pcm_shm_state,
delay: snd_pcm_shm_delay,
@ -578,7 +589,22 @@ static int make_inet_socket(const char *host, int port)
}
#endif
int snd_pcm_shm_open(snd_pcm_t **pcmp, const char *name, const char *sockname, const char *sname, snd_pcm_stream_t stream, int mode)
/**
* \brief Creates a new shared memory PCM
* \param pcmp Returns created PCM handle
* \param name Name of PCM
* \param sockname Unix socket name
* \param sname Server name
* \param stream PCM Stream
* \param mode PCM Mode
* \retval zero on success otherwise a negative error code
* \warning Using of this function might be dangerous in the sense
* of compatibility reasons. The prototype might be freely
* changed in future.
*/
int snd_pcm_shm_open(snd_pcm_t **pcmp, const char *name,
const char *sockname, const char *sname,
snd_pcm_stream_t stream, int mode)
{
snd_pcm_t *pcm;
snd_pcm_shm_t *shm = NULL;
@ -679,6 +705,7 @@ int snd_pcm_shm_open(snd_pcm_t **pcmp, const char *name, const char *sockname, c
return result;
}
#ifndef DOC_HIDDEN
int is_local(struct hostent *hent)
{
int s;
@ -723,7 +750,45 @@ int is_local(struct hostent *hent)
free(conf.ifc_buf);
return i < numreqs;
}
#endif
/*! \page pcm_plugins
\section pcm_plugins_shm Plugin: shm
This plugin communicates with aserver via shared memory. It is a raw
communication without any conversions, but it can be expected worse
performance.
\code
pcm.name {
type shm # Shared memory PCM
server STR # Server name
pcm STR # PCM name
}
\endcode
\subsection pcm_plugins_shm_funcref Function reference
<UL>
<LI>snd_pcm_shm_open()
<LI>_snd_pcm_shm_open()
</UL>
*/
/**
* \brief Creates a new shm PCM
* \param pcmp Returns created PCM handle
* \param name Name of PCM
* \param root Root configuration node
* \param conf Configuration node with hw PCM description
* \param stream PCM Stream
* \param mode PCM Mode
* \warning Using of this function might be dangerous in the sense
* of compatibility reasons. The prototype might be freely
* changed in future.
*/
int _snd_pcm_shm_open(snd_pcm_t **pcmp, const char *name,
snd_config_t *root, snd_config_t *conf,
snd_pcm_stream_t stream, int mode)
@ -841,4 +906,6 @@ int _snd_pcm_shm_open(snd_pcm_t **pcmp, const char *name,
snd_config_delete(sconfig);
return err;
}
#ifndef DOC_HIDDEN
SND_DLSYM_BUILD_VERSION(_snd_pcm_shm_open, SND_PCM_DLSYM_VERSION);
#endif