More documentation for burn_source, new API call burn_fifo_inquire_status()

This commit is contained in:
Thomas Schmitt 2007-10-03 22:37:39 +00:00
parent 291ef125b0
commit e2479d6088
2 changed files with 48 additions and 18 deletions

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@ -1 +1 @@
#define Cdrskin_timestamP "2007.10.03.223649"
#define Cdrskin_timestamP "2007.10.03.223851"

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@ -322,31 +322,38 @@ struct burn_toc_entry
This allows to use arbitrary program code as provider of track input data.
Objects compliant to this interface are either provided by the application
or by API calls of libburn: burn_fd_source_new() , burn_file_source_new().
Those calls allow to use any file object as data source. Consider to feed
your data stream asynchronously into a file descriptor and to let libburn
handle the rest.
or by API calls of libburn: burn_fd_source_new() , burn_file_source_new(),
and burn_fifo_source_new().
If you need to implement an own passive data producer by this interface,
The API calls allow to use any file object as data source. Consider to feed
an eventual custom data stream asynchronously into a pipe(2) and to let
libburn handle the rest.
In this case the following rule applies:
Call burn_source_free() exactly once for every source obtained from
libburn API. You MUST NOT otherwise use or manipulate its components.
In general, burn_source objects can be freed as soon as they are attached
to track objects. The track objects will keep them alive and dispose them
when they are no longer needed.
The following description of burn_source applies only to application
implemented burn_source objects. You need not to know it for API provided
ones.
If you really implement an own passive data producer by this interface,
then beware: it can do anything and it can spoil everything.
If implemented by the application then the functions (*read), (*get_size),
(*set_size), (*free_data) MUST be implemented and attached to the object
at creation time.
Function (*read_sub) is allowed to be NULL (or MUST be implemented).
In this case the functions (*read), (*get_size), (*set_size), (*free_data)
MUST be implemented by the application and attached to the object at
creation time.
Function (*read_sub) is allowed to be NULL or it MUST be implemented and
attached.
burn_source.refcount MUST be handled properly: If not exactly as many
references are freed as have been obtained, then either memory leaks or
corrupted memory are the consequence.
All objects which are referred to by *data must be kept existent until
(*free_data) is called via burn_source_free() by the last referer.
With libburn provided burn_source objects the following rule applies:
Call burn_source_free() exactly once for every source obtained from
libburn API. You MUST NOT otherwise manipulate its refcount.
The following component description applies to application implemented
burn_source objects only. You need not to know it for API provided ones.
*/
struct burn_source {
@ -1459,8 +1466,13 @@ struct burn_source *burn_fd_source_new(int datafd, int subfd, off_t size);
In future this will implement a ring buffer which shall smoothen the
data stream between burn_source and writer thread.
@param inp The burn_source for which the fifo shall act as proxy.
@param chunksize The size in bytes of a chunk. Use 2048 if in doubt.
@param chunksize The size in bytes of a chunk. Use 2048 for sources
suitable for BURN_BLOCK_MODE1 and 2352 for sources
which deliver for BURN_BLOCK_AUDIO.
Some variations of burn_source might work only with
a particular chunksize. E.g. libisofs demands 2048.
@param chunks The number of chunks to be allocated in ring buffer.
This value must be >= 2.
@param flag Bitfield for control purposes (unused yet, submit 0).
@return A pointer to the newly created burn_source.
Later both burn_sources, inp and the returned fifo, have
@ -1469,6 +1481,24 @@ struct burn_source *burn_fd_source_new(int datafd, int subfd, off_t size);
struct burn_source *burn_fifo_source_new(struct burn_source *inp,
int chunksize, int chunks, int flag);
/* ts A71003 */
/** Inquires state and fill parameters of a fifo burn_source which was created
by burn_fifo_source_new() . Do not use with other burn_source variants.
@param fifo The fifo object to inquire
@param size The total size of the fifo
@param free_bytes The current free capacity of the fifo
@return <=0 error,
1=input and consumption are active
2=input has ended without error
3=input had error and ended,
5=consumption has ended prematurely
6=consumption has ended without input error
7=consumption has ended after input error
*/
int burn_fifo_inquire_status(struct burn_source *fifo, int *size,
int *free_bytes);
/* ts A70328 */
/** Sets a fixed track size after the data source object has already been
created.