Fix forward/rewind support in iec958 plugin

Commit Message

Alexander Patrakov April 23, 2014, 6:40 p.m. UTC

When forwarding or rewinding, the frame counter was not updated. This
could result in corrupted channel status words or misplaced Z-type
preamble.
---
I found the issue by inspecting the code. However, I have no hardware
to test this fix on.

 src/pcm/pcm_iec958.c | 64 +++++++++++++++++++++++++++++++++++++++++++++-
 src/pcm/pcm_plugin.c | 28 ++++++++++----------
 src/pcm/pcm_plugin.h | 72 +++++++++++++++++++++++++++++++++++++++++++++++++---
 3 files changed, 145 insertions(+), 19 deletions(-)

Comments

David Henningsson April 24, 2014, 11:19 a.m. UTC | #1

On 2014-04-23 20:40, Alexander E. Patrakov wrote:
> When forwarding or rewinding, the frame counter was not updated. This
> could result in corrupted channel status words or misplaced Z-type
> preamble.
> ---
> I found the issue by inspecting the code. However, I have no hardware
> to test this fix on.
>
>   src/pcm/pcm_iec958.c | 64 +++++++++++++++++++++++++++++++++++++++++++++-
>   src/pcm/pcm_plugin.c | 28 ++++++++++----------
>   src/pcm/pcm_plugin.h | 72 +++++++++++++++++++++++++++++++++++++++++++++++++---
>   3 files changed, 145 insertions(+), 19 deletions(-)
>
> diff --git a/src/pcm/pcm_iec958.c b/src/pcm/pcm_iec958.c
> index d81b0a1..facf683 100644
> --- a/src/pcm/pcm_iec958.c
> +++ b/src/pcm/pcm_iec958.c
> @@ -416,6 +416,35 @@ static void snd_pcm_iec958_dump(snd_pcm_t *pcm, snd_output_t *out)
>   	snd_pcm_dump(iec->plug.gen.slave, out);
>   }
>
> +static snd_pcm_sframes_t snd_pcm_iec958_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
> +{
> +	unsigned int counter_decrement;
> +	snd_pcm_iec958_t *iec = pcm->private_data;
> +	snd_pcm_sframes_t result = snd_pcm_plugin_rewind(pcm, frames);
> +	if (result <= 0)
> +		return result;
> +
> +	counter_decrement = result % 192;
> +	iec->counter += 192 - counter_decrement;
> +	iec->counter %= 192;
> +	return result;
> +}
> +
> +static snd_pcm_sframes_t snd_pcm_iec958_forward(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
> +
> +{
> +	unsigned int counter_increment;
> +	snd_pcm_iec958_t *iec = pcm->private_data;
> +	snd_pcm_sframes_t result = snd_pcm_plugin_rewind(pcm, frames);
> +	if (result <= 0)
> +		return result;
> +
> +	counter_increment = result % 192;
> +	iec->counter += counter_increment;
> +	iec->counter %= 192;
> +	return result;
> +}
> +
>   static const snd_pcm_ops_t snd_pcm_iec958_ops = {
>   	.close = snd_pcm_generic_close,
>   	.info = snd_pcm_generic_info,
> @@ -434,6 +463,39 @@ static const snd_pcm_ops_t snd_pcm_iec958_ops = {
>   	.set_chmap = snd_pcm_generic_set_chmap,
>   };
>
> +
> +static const snd_pcm_fast_ops_t snd_pcm_iec958_fast_ops = {
> +	.status = snd_pcm_plugin_status,
> +	.state = snd_pcm_generic_state,
> +	.hwsync = snd_pcm_generic_hwsync,
> +	.delay = snd_pcm_plugin_delay,
> +	.prepare = snd_pcm_plugin_prepare,
> +	.reset = snd_pcm_plugin_reset,
> +	.start = snd_pcm_generic_start,
> +	.drop = snd_pcm_generic_drop,
> +	.drain = snd_pcm_generic_drain,
> +	.pause = snd_pcm_generic_pause,
> +	.rewindable = snd_pcm_plugin_rewindable,
> +	.rewind = snd_pcm_iec958_rewind,
> +	.forwardable = snd_pcm_plugin_forwardable,
> +	.forward = snd_pcm_iec958_forward,
> +	.resume = snd_pcm_generic_resume,
> +	.link = snd_pcm_generic_link,
> +	.link_slaves = snd_pcm_generic_link_slaves,
> +	.unlink = snd_pcm_generic_unlink,
> +	.writei = snd_pcm_plugin_writei,
> +	.writen = snd_pcm_plugin_writen,
> +	.readi = snd_pcm_plugin_readi,
> +	.readn = snd_pcm_plugin_readn,
> +	.avail_update = snd_pcm_plugin_avail_update,
> +	.mmap_commit = snd_pcm_plugin_mmap_commit,
> +	.htimestamp = snd_pcm_generic_htimestamp,
> +	.poll_descriptors_count = snd_pcm_generic_poll_descriptors_count,
> +	.poll_descriptors = snd_pcm_generic_poll_descriptors,
> +	.poll_revents = snd_pcm_generic_poll_revents,
> +	.may_wait_for_avail_min = snd_pcm_generic_may_wait_for_avail_min,
> +};
> +
>   /**
>    * \brief Creates a new IEC958 subframe conversion PCM
>    * \param pcmp Returns created PCM handle
> @@ -495,7 +557,7 @@ int snd_pcm_iec958_open(snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sfo
>   		return err;
>   	}
>   	pcm->ops = &snd_pcm_iec958_ops;
> -	pcm->fast_ops = &snd_pcm_plugin_fast_ops;
> +	pcm->fast_ops = &snd_pcm_iec958_fast_ops;

Instead of making all pcm_plugin functions public, you can consider 
something like this:

ptr = malloc(sizeof(snd_pcm_fast_ops_t));
*ptr = snd_pcm_plugin_fast_ops;
ptr->rewind = snd_pcm_iec958_rewind;
ptr->forward = snd_pcm_iec958_forward;

pcm->fast_ops = ptr;

(and deallocate ptr somewhere else)

>   	pcm->private_data = iec;
>   	pcm->poll_fd = slave->poll_fd;
>   	pcm->poll_events = slave->poll_events;
> diff --git a/src/pcm/pcm_plugin.c b/src/pcm/pcm_plugin.c
> index 17157e8..022d908 100644
> --- a/src/pcm/pcm_plugin.c
> +++ b/src/pcm/pcm_plugin.c
> @@ -137,7 +137,7 @@ void snd_pcm_plugin_init(snd_pcm_plugin_t *plugin)
>   	snd_atomic_write_init(&plugin->watom);
>   }
>
> -static int snd_pcm_plugin_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delayp)
> +int snd_pcm_plugin_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delayp)
>   {
>   	snd_pcm_plugin_t *plugin = pcm->private_data;
>   	snd_pcm_sframes_t sd;
> @@ -154,7 +154,7 @@ static int snd_pcm_plugin_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delayp)
>   	return 0;
>   }
>
> -static int snd_pcm_plugin_prepare(snd_pcm_t *pcm)
> +int snd_pcm_plugin_prepare(snd_pcm_t *pcm)
>   {
>   	snd_pcm_plugin_t *plugin = pcm->private_data;
>   	int err;
> @@ -175,7 +175,7 @@ static int snd_pcm_plugin_prepare(snd_pcm_t *pcm)
>   	return 0;
>   }
>
> -static int snd_pcm_plugin_reset(snd_pcm_t *pcm)
> +int snd_pcm_plugin_reset(snd_pcm_t *pcm)
>   {
>   	snd_pcm_plugin_t *plugin = pcm->private_data;
>   	int err;
> @@ -196,12 +196,12 @@ static int snd_pcm_plugin_reset(snd_pcm_t *pcm)
>   	return 0;
>   }
>
> -static snd_pcm_sframes_t snd_pcm_plugin_rewindable(snd_pcm_t *pcm)
> +snd_pcm_sframes_t snd_pcm_plugin_rewindable(snd_pcm_t *pcm)
>   {
>   	return snd_pcm_mmap_hw_avail(pcm);
>   }
>
> -static snd_pcm_sframes_t snd_pcm_plugin_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
> +snd_pcm_sframes_t snd_pcm_plugin_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
>   {
>   	snd_pcm_plugin_t *plugin = pcm->private_data;
>   	snd_pcm_sframes_t n = snd_pcm_mmap_hw_avail(pcm);
> @@ -224,12 +224,12 @@ static snd_pcm_sframes_t snd_pcm_plugin_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t
>   	return (snd_pcm_sframes_t) sframes;
>   }
>
> -static snd_pcm_sframes_t snd_pcm_plugin_forwardable(snd_pcm_t *pcm)
> +snd_pcm_sframes_t snd_pcm_plugin_forwardable(snd_pcm_t *pcm)
>   {
>   	return snd_pcm_mmap_avail(pcm);
>   }
>
> -static snd_pcm_sframes_t snd_pcm_plugin_forward(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
> +snd_pcm_sframes_t snd_pcm_plugin_forward(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
>   {
>   	snd_pcm_plugin_t *plugin = pcm->private_data;
>   	snd_pcm_sframes_t n = snd_pcm_mmap_avail(pcm);
> @@ -347,7 +347,7 @@ static snd_pcm_sframes_t snd_pcm_plugin_read_areas(snd_pcm_t *pcm,
>   }
>
>
> -static snd_pcm_sframes_t
> +snd_pcm_sframes_t
>   snd_pcm_plugin_writei(snd_pcm_t *pcm, const void *buffer, snd_pcm_uframes_t size)
>   {
>   	snd_pcm_channel_area_t areas[pcm->channels];
> @@ -356,7 +356,7 @@ snd_pcm_plugin_writei(snd_pcm_t *pcm, const void *buffer, snd_pcm_uframes_t size
>   				   snd_pcm_plugin_write_areas);
>   }
>
> -static snd_pcm_sframes_t
> +snd_pcm_sframes_t
>   snd_pcm_plugin_writen(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t size)
>   {
>   	snd_pcm_channel_area_t areas[pcm->channels];
> @@ -365,7 +365,7 @@ snd_pcm_plugin_writen(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t size)
>   				   snd_pcm_plugin_write_areas);
>   }
>
> -static snd_pcm_sframes_t
> +snd_pcm_sframes_t
>   snd_pcm_plugin_readi(snd_pcm_t *pcm, void *buffer, snd_pcm_uframes_t size)
>   {
>   	snd_pcm_channel_area_t areas[pcm->channels];
> @@ -374,7 +374,7 @@ snd_pcm_plugin_readi(snd_pcm_t *pcm, void *buffer, snd_pcm_uframes_t size)
>   				  snd_pcm_plugin_read_areas);
>   }
>
> -static snd_pcm_sframes_t
> +snd_pcm_sframes_t
>   snd_pcm_plugin_readn(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t size)
>   {
>   	snd_pcm_channel_area_t areas[pcm->channels];
> @@ -383,7 +383,7 @@ snd_pcm_plugin_readn(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t size)
>   				  snd_pcm_plugin_read_areas);
>   }
>
> -static snd_pcm_sframes_t
> +snd_pcm_sframes_t
>   snd_pcm_plugin_mmap_commit(snd_pcm_t *pcm,
>   			   snd_pcm_uframes_t offset ATTRIBUTE_UNUSED,
>   			   snd_pcm_uframes_t size)
> @@ -452,7 +452,7 @@ snd_pcm_plugin_mmap_commit(snd_pcm_t *pcm,
>   	return xfer;
>   }
>
> -static snd_pcm_sframes_t snd_pcm_plugin_avail_update(snd_pcm_t *pcm)
> +snd_pcm_sframes_t snd_pcm_plugin_avail_update(snd_pcm_t *pcm)
>   {
>   	snd_pcm_plugin_t *plugin = pcm->private_data;
>   	snd_pcm_t *slave = plugin->gen.slave;
> @@ -516,7 +516,7 @@ static snd_pcm_sframes_t snd_pcm_plugin_avail_update(snd_pcm_t *pcm)
>   	}
>   }
>
> -static int snd_pcm_plugin_status(snd_pcm_t *pcm, snd_pcm_status_t * status)
> +int snd_pcm_plugin_status(snd_pcm_t *pcm, snd_pcm_status_t * status)
>   {
>   	snd_pcm_plugin_t *plugin = pcm->private_data;
>   	snd_pcm_sframes_t err;
> diff --git a/src/pcm/pcm_plugin.h b/src/pcm/pcm_plugin.h
> index 7ee7c7f..7734369 100644
> --- a/src/pcm/pcm_plugin.h
> +++ b/src/pcm/pcm_plugin.h
> @@ -50,14 +50,42 @@ typedef struct {
>   } snd_pcm_plugin_t;	
>
>   /* make local functions really local */
> -#define snd_pcm_plugin_init \
> -	snd1_pcm_plugin_init
> -#define snd_pcm_plugin_fast_ops \
> -	snd1_pcm_plugin_fast_ops
>   #define snd_pcm_plugin_undo_read_generic \
>   	snd1_pcm_plugin_undo_read_generic
>   #define snd_pcm_plugin_undo_write_generic \
>   	snd1_pcm_plugin_undo_write_generic
> +#define snd_pcm_plugin_init \
> +	snd1_pcm_plugin_init
> +#define snd_pcm_plugin_delay \
> +	snd1_pcm_plugin_delay
> +#define snd_pcm_plugin_prepare \
> +	snd1_pcm_plugin_prepare
> +#define snd_pcm_plugin_reset \
> +	snd1_pcm_plugin_reset
> +#define snd_pcm_plugin_rewindable \
> +	snd1_pcm_plugin_rewindable
> +#define snd_pcm_plugin_rewind \
> +	snd1_pcm_plugin_rewind
> +#define snd_pcm_plugin_forwardable \
> +	snd1_pcm_plugin_forwardable
> +#define snd_pcm_plugin_forward \
> +	snd1_pcm_plugin_forward
> +#define snd_pcm_plugin_writei \
> +	snd1_pcm_plugin_writei
> +#define snd_pcm_plugin_writen \
> +	snd1_pcm_plugin_writen
> +#define snd_pcm_plugin_readi \
> +	snd1_pcm_plugin_readi
> +#define snd_pcm_plugin_readn \
> +	snd1_pcm_plugin_readn
> +#define snd_pcm_plugin_mmap_commit \
> +	snd1_pcm_plugin_mmap_commit
> +#define snd_pcm_plugin_avail_update \
> +	snd1_pcm_plugin_avail_update
> +#define snd_pcm_plugin_status \
> +	snd1_pcm_plugin_status
> +#define snd_pcm_plugin_fast_ops \
> +	snd1_pcm_plugin_fast_ops
>
>   void snd_pcm_plugin_init(snd_pcm_plugin_t *plugin);
>
> @@ -77,6 +105,42 @@ snd_pcm_sframes_t snd_pcm_plugin_undo_write_generic
>         snd_pcm_uframes_t res_size,		/* size of result areas */
>         snd_pcm_uframes_t slave_undo_size);
>
> +int snd_pcm_plugin_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delayp);
> +int snd_pcm_plugin_prepare(snd_pcm_t *pcm);
> +int snd_pcm_plugin_reset(snd_pcm_t *pcm);
> +snd_pcm_sframes_t snd_pcm_plugin_rewindable(snd_pcm_t *pcm);
> +snd_pcm_sframes_t snd_pcm_plugin_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t frames);
> +snd_pcm_sframes_t snd_pcm_plugin_forwardable(snd_pcm_t *pcm);
> +snd_pcm_sframes_t snd_pcm_plugin_forward(snd_pcm_t *pcm, snd_pcm_uframes_t frames);
> +
> +snd_pcm_sframes_t snd_pcm_plugin_writei
> +      (snd_pcm_t *pcm,
> +       const void *buffer,
> +       snd_pcm_uframes_t size);
> +
> +snd_pcm_sframes_t snd_pcm_plugin_writen
> +      (snd_pcm_t *pcm,
> +       void **bufs,
> +       snd_pcm_uframes_t size);
> +
> +snd_pcm_sframes_t snd_pcm_plugin_readi
> +      (snd_pcm_t *pcm,
> +       void *buffer,
> +       snd_pcm_uframes_t size);
> +
> +snd_pcm_sframes_t snd_pcm_plugin_readn
> +      (snd_pcm_t *pcm,
> +       void **bufs,
> +       snd_pcm_uframes_t size);
> +
> +snd_pcm_sframes_t snd_pcm_plugin_mmap_commit
> +      (snd_pcm_t *pcm,
> +       snd_pcm_uframes_t offset,
> +       snd_pcm_uframes_t size);
> +
> +snd_pcm_sframes_t snd_pcm_plugin_avail_update(snd_pcm_t *pcm);
> +int snd_pcm_plugin_status(snd_pcm_t *pcm, snd_pcm_status_t * status);
> +
>   /* make local functions really local */
>   #define snd_pcm_linear_get_index	snd1_pcm_linear_get_index
>   #define snd_pcm_linear_put_index	snd1_pcm_linear_put_index
>

Patch

diff --git a/src/pcm/pcm_iec958.c b/src/pcm/pcm_iec958.c
index d81b0a1..facf683 100644
--- a/src/pcm/pcm_iec958.c
+++ b/src/pcm/pcm_iec958.c
@@ -416,6 +416,35 @@  static void snd_pcm_iec958_dump(snd_pcm_t *pcm, snd_output_t *out)
 	snd_pcm_dump(iec->plug.gen.slave, out);
 }
 
+static snd_pcm_sframes_t snd_pcm_iec958_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
+{
+	unsigned int counter_decrement;
+	snd_pcm_iec958_t *iec = pcm->private_data;
+	snd_pcm_sframes_t result = snd_pcm_plugin_rewind(pcm, frames);
+	if (result <= 0)
+		return result;
+
+	counter_decrement = result % 192;
+	iec->counter += 192 - counter_decrement;
+	iec->counter %= 192;
+	return result;
+}
+
+static snd_pcm_sframes_t snd_pcm_iec958_forward(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
+
+{
+	unsigned int counter_increment;
+	snd_pcm_iec958_t *iec = pcm->private_data;
+	snd_pcm_sframes_t result = snd_pcm_plugin_rewind(pcm, frames);
+	if (result <= 0)
+		return result;
+
+	counter_increment = result % 192;
+	iec->counter += counter_increment;
+	iec->counter %= 192;
+	return result;
+}
+
 static const snd_pcm_ops_t snd_pcm_iec958_ops = {
 	.close = snd_pcm_generic_close,
 	.info = snd_pcm_generic_info,
@@ -434,6 +463,39 @@  static const snd_pcm_ops_t snd_pcm_iec958_ops = {
 	.set_chmap = snd_pcm_generic_set_chmap,
 };
 
+
+static const snd_pcm_fast_ops_t snd_pcm_iec958_fast_ops = {
+	.status = snd_pcm_plugin_status,
+	.state = snd_pcm_generic_state,
+	.hwsync = snd_pcm_generic_hwsync,
+	.delay = snd_pcm_plugin_delay,
+	.prepare = snd_pcm_plugin_prepare,
+	.reset = snd_pcm_plugin_reset,
+	.start = snd_pcm_generic_start,
+	.drop = snd_pcm_generic_drop,
+	.drain = snd_pcm_generic_drain,
+	.pause = snd_pcm_generic_pause,
+	.rewindable = snd_pcm_plugin_rewindable,
+	.rewind = snd_pcm_iec958_rewind,
+	.forwardable = snd_pcm_plugin_forwardable,
+	.forward = snd_pcm_iec958_forward,
+	.resume = snd_pcm_generic_resume,
+	.link = snd_pcm_generic_link,
+	.link_slaves = snd_pcm_generic_link_slaves,
+	.unlink = snd_pcm_generic_unlink,
+	.writei = snd_pcm_plugin_writei,
+	.writen = snd_pcm_plugin_writen,
+	.readi = snd_pcm_plugin_readi,
+	.readn = snd_pcm_plugin_readn,
+	.avail_update = snd_pcm_plugin_avail_update,
+	.mmap_commit = snd_pcm_plugin_mmap_commit,
+	.htimestamp = snd_pcm_generic_htimestamp,
+	.poll_descriptors_count = snd_pcm_generic_poll_descriptors_count,
+	.poll_descriptors = snd_pcm_generic_poll_descriptors,
+	.poll_revents = snd_pcm_generic_poll_revents,
+	.may_wait_for_avail_min = snd_pcm_generic_may_wait_for_avail_min,
+};
+
 /**
  * \brief Creates a new IEC958 subframe conversion PCM
  * \param pcmp Returns created PCM handle
@@ -495,7 +557,7 @@  int snd_pcm_iec958_open(snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sfo
 		return err;
 	}
 	pcm->ops = &snd_pcm_iec958_ops;
-	pcm->fast_ops = &snd_pcm_plugin_fast_ops;
+	pcm->fast_ops = &snd_pcm_iec958_fast_ops;
 	pcm->private_data = iec;
 	pcm->poll_fd = slave->poll_fd;
 	pcm->poll_events = slave->poll_events;
diff --git a/src/pcm/pcm_plugin.c b/src/pcm/pcm_plugin.c
index 17157e8..022d908 100644
--- a/src/pcm/pcm_plugin.c
+++ b/src/pcm/pcm_plugin.c
@@ -137,7 +137,7 @@  void snd_pcm_plugin_init(snd_pcm_plugin_t *plugin)
 	snd_atomic_write_init(&plugin->watom);
 }
 
-static int snd_pcm_plugin_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delayp)
+int snd_pcm_plugin_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delayp)
 {
 	snd_pcm_plugin_t *plugin = pcm->private_data;
 	snd_pcm_sframes_t sd;
@@ -154,7 +154,7 @@  static int snd_pcm_plugin_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delayp)
 	return 0;
 }
 
-static int snd_pcm_plugin_prepare(snd_pcm_t *pcm)
+int snd_pcm_plugin_prepare(snd_pcm_t *pcm)
 {
 	snd_pcm_plugin_t *plugin = pcm->private_data;
 	int err;
@@ -175,7 +175,7 @@  static int snd_pcm_plugin_prepare(snd_pcm_t *pcm)
 	return 0;
 }
 
-static int snd_pcm_plugin_reset(snd_pcm_t *pcm)
+int snd_pcm_plugin_reset(snd_pcm_t *pcm)
 {
 	snd_pcm_plugin_t *plugin = pcm->private_data;
 	int err;
@@ -196,12 +196,12 @@  static int snd_pcm_plugin_reset(snd_pcm_t *pcm)
 	return 0;
 }
 
-static snd_pcm_sframes_t snd_pcm_plugin_rewindable(snd_pcm_t *pcm)
+snd_pcm_sframes_t snd_pcm_plugin_rewindable(snd_pcm_t *pcm)
 {
 	return snd_pcm_mmap_hw_avail(pcm);
 }
 
-static snd_pcm_sframes_t snd_pcm_plugin_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
+snd_pcm_sframes_t snd_pcm_plugin_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
 {
 	snd_pcm_plugin_t *plugin = pcm->private_data;
 	snd_pcm_sframes_t n = snd_pcm_mmap_hw_avail(pcm);
@@ -224,12 +224,12 @@  static snd_pcm_sframes_t snd_pcm_plugin_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t
 	return (snd_pcm_sframes_t) sframes;
 }
 
-static snd_pcm_sframes_t snd_pcm_plugin_forwardable(snd_pcm_t *pcm)
+snd_pcm_sframes_t snd_pcm_plugin_forwardable(snd_pcm_t *pcm)
 {
 	return snd_pcm_mmap_avail(pcm);
 }
 
-static snd_pcm_sframes_t snd_pcm_plugin_forward(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
+snd_pcm_sframes_t snd_pcm_plugin_forward(snd_pcm_t *pcm, snd_pcm_uframes_t frames)
 {
 	snd_pcm_plugin_t *plugin = pcm->private_data;
 	snd_pcm_sframes_t n = snd_pcm_mmap_avail(pcm);
@@ -347,7 +347,7 @@  static snd_pcm_sframes_t snd_pcm_plugin_read_areas(snd_pcm_t *pcm,
 }
 
 
-static snd_pcm_sframes_t
+snd_pcm_sframes_t
 snd_pcm_plugin_writei(snd_pcm_t *pcm, const void *buffer, snd_pcm_uframes_t size)
 {
 	snd_pcm_channel_area_t areas[pcm->channels];
@@ -356,7 +356,7 @@  snd_pcm_plugin_writei(snd_pcm_t *pcm, const void *buffer, snd_pcm_uframes_t size
 				   snd_pcm_plugin_write_areas);
 }
 
-static snd_pcm_sframes_t
+snd_pcm_sframes_t
 snd_pcm_plugin_writen(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t size)
 {
 	snd_pcm_channel_area_t areas[pcm->channels];
@@ -365,7 +365,7 @@  snd_pcm_plugin_writen(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t size)
 				   snd_pcm_plugin_write_areas);
 }
 
-static snd_pcm_sframes_t
+snd_pcm_sframes_t
 snd_pcm_plugin_readi(snd_pcm_t *pcm, void *buffer, snd_pcm_uframes_t size)
 {
 	snd_pcm_channel_area_t areas[pcm->channels];
@@ -374,7 +374,7 @@  snd_pcm_plugin_readi(snd_pcm_t *pcm, void *buffer, snd_pcm_uframes_t size)
 				  snd_pcm_plugin_read_areas);
 }
 
-static snd_pcm_sframes_t
+snd_pcm_sframes_t
 snd_pcm_plugin_readn(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t size)
 {
 	snd_pcm_channel_area_t areas[pcm->channels];
@@ -383,7 +383,7 @@  snd_pcm_plugin_readn(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t size)
 				  snd_pcm_plugin_read_areas);
 }
 
-static snd_pcm_sframes_t
+snd_pcm_sframes_t
 snd_pcm_plugin_mmap_commit(snd_pcm_t *pcm,
 			   snd_pcm_uframes_t offset ATTRIBUTE_UNUSED,
 			   snd_pcm_uframes_t size)
@@ -452,7 +452,7 @@  snd_pcm_plugin_mmap_commit(snd_pcm_t *pcm,
 	return xfer;
 }
 
-static snd_pcm_sframes_t snd_pcm_plugin_avail_update(snd_pcm_t *pcm)
+snd_pcm_sframes_t snd_pcm_plugin_avail_update(snd_pcm_t *pcm)
 {
 	snd_pcm_plugin_t *plugin = pcm->private_data;
 	snd_pcm_t *slave = plugin->gen.slave;
@@ -516,7 +516,7 @@  static snd_pcm_sframes_t snd_pcm_plugin_avail_update(snd_pcm_t *pcm)
 	}
 }
 
-static int snd_pcm_plugin_status(snd_pcm_t *pcm, snd_pcm_status_t * status)
+int snd_pcm_plugin_status(snd_pcm_t *pcm, snd_pcm_status_t * status)
 {
 	snd_pcm_plugin_t *plugin = pcm->private_data;
 	snd_pcm_sframes_t err;
diff --git a/src/pcm/pcm_plugin.h b/src/pcm/pcm_plugin.h
index 7ee7c7f..7734369 100644
--- a/src/pcm/pcm_plugin.h
+++ b/src/pcm/pcm_plugin.h
@@ -50,14 +50,42 @@  typedef struct {
 } snd_pcm_plugin_t;	
 
 /* make local functions really local */
-#define snd_pcm_plugin_init \
-	snd1_pcm_plugin_init
-#define snd_pcm_plugin_fast_ops \
-	snd1_pcm_plugin_fast_ops
 #define snd_pcm_plugin_undo_read_generic \
 	snd1_pcm_plugin_undo_read_generic
 #define snd_pcm_plugin_undo_write_generic \
 	snd1_pcm_plugin_undo_write_generic
+#define snd_pcm_plugin_init \
+	snd1_pcm_plugin_init
+#define snd_pcm_plugin_delay \
+	snd1_pcm_plugin_delay
+#define snd_pcm_plugin_prepare \
+	snd1_pcm_plugin_prepare
+#define snd_pcm_plugin_reset \
+	snd1_pcm_plugin_reset
+#define snd_pcm_plugin_rewindable \
+	snd1_pcm_plugin_rewindable
+#define snd_pcm_plugin_rewind \
+	snd1_pcm_plugin_rewind
+#define snd_pcm_plugin_forwardable \
+	snd1_pcm_plugin_forwardable
+#define snd_pcm_plugin_forward \
+	snd1_pcm_plugin_forward
+#define snd_pcm_plugin_writei \
+	snd1_pcm_plugin_writei
+#define snd_pcm_plugin_writen \
+	snd1_pcm_plugin_writen
+#define snd_pcm_plugin_readi \
+	snd1_pcm_plugin_readi
+#define snd_pcm_plugin_readn \
+	snd1_pcm_plugin_readn
+#define snd_pcm_plugin_mmap_commit \
+	snd1_pcm_plugin_mmap_commit
+#define snd_pcm_plugin_avail_update \
+	snd1_pcm_plugin_avail_update
+#define snd_pcm_plugin_status \
+	snd1_pcm_plugin_status
+#define snd_pcm_plugin_fast_ops \
+	snd1_pcm_plugin_fast_ops
 
 void snd_pcm_plugin_init(snd_pcm_plugin_t *plugin);
 
@@ -77,6 +105,42 @@  snd_pcm_sframes_t snd_pcm_plugin_undo_write_generic
       snd_pcm_uframes_t res_size,		/* size of result areas */
       snd_pcm_uframes_t slave_undo_size);
 
+int snd_pcm_plugin_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delayp);
+int snd_pcm_plugin_prepare(snd_pcm_t *pcm);
+int snd_pcm_plugin_reset(snd_pcm_t *pcm);
+snd_pcm_sframes_t snd_pcm_plugin_rewindable(snd_pcm_t *pcm);
+snd_pcm_sframes_t snd_pcm_plugin_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t frames);
+snd_pcm_sframes_t snd_pcm_plugin_forwardable(snd_pcm_t *pcm);
+snd_pcm_sframes_t snd_pcm_plugin_forward(snd_pcm_t *pcm, snd_pcm_uframes_t frames);
+
+snd_pcm_sframes_t snd_pcm_plugin_writei
+      (snd_pcm_t *pcm,
+       const void *buffer,
+       snd_pcm_uframes_t size);
+
+snd_pcm_sframes_t snd_pcm_plugin_writen
+      (snd_pcm_t *pcm,
+       void **bufs,
+       snd_pcm_uframes_t size);
+
+snd_pcm_sframes_t snd_pcm_plugin_readi
+      (snd_pcm_t *pcm,
+       void *buffer,
+       snd_pcm_uframes_t size);
+
+snd_pcm_sframes_t snd_pcm_plugin_readn
+      (snd_pcm_t *pcm,
+       void **bufs,
+       snd_pcm_uframes_t size);
+
+snd_pcm_sframes_t snd_pcm_plugin_mmap_commit
+      (snd_pcm_t *pcm,
+       snd_pcm_uframes_t offset,
+       snd_pcm_uframes_t size);
+
+snd_pcm_sframes_t snd_pcm_plugin_avail_update(snd_pcm_t *pcm);
+int snd_pcm_plugin_status(snd_pcm_t *pcm, snd_pcm_status_t * status);
+
 /* make local functions really local */
 #define snd_pcm_linear_get_index	snd1_pcm_linear_get_index
 #define snd_pcm_linear_put_index	snd1_pcm_linear_put_index