172 lines
7.4 KiB
C
172 lines
7.4 KiB
C
|
|
||
|
|
/*
|
||
|
|
cdrfifo.c , Copyright 2006 Thomas Schmitt <scdbackup@gmx.net>
|
||
|
|
|
||
|
|
A fd-to-fd or fd-to-memory fifo to be used within cdrskin or independently.
|
||
|
|
By chaining of fifo objects, several fifos can be run simultaneously
|
||
|
|
in fd-to-fd mode. Modes are controlled by parameter flag of
|
||
|
|
Cdrfifo_try_to_work().
|
||
|
|
|
||
|
|
Provided under GPL license within cdrskin and under BSD license elsewise.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#ifndef Cdrfifo_headerfile_includeD
|
||
|
|
#define Cdrfifo_headerfile_includeD
|
||
|
|
|
||
|
|
|
||
|
|
/** The fifo buffer which will smoothen the data stream from data provider
|
||
|
|
to data consumer. Although this is not a mandatory lifesaver for modern
|
||
|
|
burners any more, a fifo can speed up burning of data which is delivered
|
||
|
|
with varying bandwidths (e.g. compressed archives created on the fly
|
||
|
|
or mkisofs running at its speed limit.).
|
||
|
|
This structure is opaque to applications and may only be used via
|
||
|
|
the Cdrfifo*() methods described in cdrfifo.h .
|
||
|
|
*/
|
||
|
|
struct CdrfifO;
|
||
|
|
|
||
|
|
|
||
|
|
/** Create a fifo object.
|
||
|
|
@param ff Returns the address of the new object.
|
||
|
|
@param source_fd Filedescriptor opened to a readable data stream.
|
||
|
|
@param dest_fd Filedescriptor opened to a writable data stream.
|
||
|
|
To work with libburn, it needs to be attached to a
|
||
|
|
struct burn_source object.
|
||
|
|
@param chunk_size Size of buffer block for a single transaction (0=default)
|
||
|
|
@param buffer_size Size of fifo buffer
|
||
|
|
@param flag bit0= Debugging verbosity
|
||
|
|
@return 1 on success, <=0 on failure
|
||
|
|
*/
|
||
|
|
int Cdrfifo_new(struct CdrfifO **ff, int source_fd, int dest_fd,
|
||
|
|
int chunk_size, int buffer_size, int flag);
|
||
|
|
|
||
|
|
/** Release from memory a fifo object previously created by Cdrfifo_new().
|
||
|
|
@param ff The victim (gets returned as NULL, call can stand *ff==NULL)
|
||
|
|
@param flag Bitfield for control purposes:
|
||
|
|
bit0= do not close destination fd
|
||
|
|
*/
|
||
|
|
int Cdrfifo_destroy(struct CdrfifO **ff, int flag);
|
||
|
|
|
||
|
|
/** Close any output fds */
|
||
|
|
int Cdrfifo_close(struct CdrfifO *o, int flag);
|
||
|
|
|
||
|
|
/** Close any output fds of o and its chain peers */
|
||
|
|
int Cdrfifo_close_all(struct CdrfifO *o, int flag);
|
||
|
|
|
||
|
|
int Cdrfifo_get_sizes(struct CdrfifO *o, int *chunk_size, int *buffer_size,
|
||
|
|
int flag);
|
||
|
|
|
||
|
|
/** Set a speed limit for buffer output.
|
||
|
|
@param o The fifo object
|
||
|
|
@param bytes_per_second >0 catch up slowdowns over the whole run time
|
||
|
|
<0 catch up slowdowns only over one interval
|
||
|
|
=0 disable speed limit
|
||
|
|
*/
|
||
|
|
int Cdrfifo_set_speed_limit(struct CdrfifO *o, double bytes_per_second,
|
||
|
|
int flag);
|
||
|
|
|
||
|
|
/** Set a fixed size for input in order to cut off any unwanted tail
|
||
|
|
@param o The fifo object
|
||
|
|
@param idx index for fds attached via Cdrfifo_attach_follow_up_fds(),
|
||
|
|
first attached is 0, <0 directs limit to active fd limit
|
||
|
|
(i.e. first track is -1, second track is 0, third is 1, ...)
|
||
|
|
*/
|
||
|
|
int Cdrfifo_set_fd_in_limit(struct CdrfifO *o, double fd_in_limit, int idx,
|
||
|
|
int flag);
|
||
|
|
|
||
|
|
|
||
|
|
int Cdrfifo_set_fds(struct CdrfifO *o, int source_fd, int dest_fd, int flag);
|
||
|
|
int Cdrfifo_get_fds(struct CdrfifO *o, int *source_fd, int *dest_fd, int flag);
|
||
|
|
|
||
|
|
|
||
|
|
/** Attach a further pair of input and output fd which will use the same
|
||
|
|
fifo buffer when its predecessors are exhausted. Reading will start as
|
||
|
|
soon as reading of the predecessor encounters EOF. Writing will start
|
||
|
|
as soon as all pending predecessor data are written.
|
||
|
|
@return index number of new item + 1, <=0 indicates error
|
||
|
|
*/
|
||
|
|
int Cdrfifo_attach_follow_up_fds(struct CdrfifO *o, int source_fd, int dest_fd,
|
||
|
|
int flag);
|
||
|
|
|
||
|
|
/** Attach a further fifo which shall be processed simultaneously with this
|
||
|
|
one by Cdrfifo_try_to_work() in fd-to-fd mode.
|
||
|
|
*/
|
||
|
|
int Cdrfifo_attach_peer(struct CdrfifO *o, struct CdrfifO *next, int flag);
|
||
|
|
|
||
|
|
|
||
|
|
/** Obtain buffer state.
|
||
|
|
@param o The buffer object
|
||
|
|
@param fill Returns the number of pending payload bytes in the buffer
|
||
|
|
@param space Returns the number of unused buffer bytes
|
||
|
|
@param flag unused yet
|
||
|
|
@return -1=error , 0=inactive , 1=reading and writing ,
|
||
|
|
2=reading ended (but still writing)
|
||
|
|
*/
|
||
|
|
int Cdrfifo_get_buffer_state(struct CdrfifO *o,int *fill,int *space,int flag);
|
||
|
|
|
||
|
|
int Cdrfifo_get_counters(struct CdrfifO *o,
|
||
|
|
double *in_counter, double *out_counter, int flag);
|
||
|
|
|
||
|
|
/** reads min_fill and begins measurement interval for next min_fill */
|
||
|
|
int Cdrfifo_next_interval(struct CdrfifO *o, int *min_fill, int flag);
|
||
|
|
|
||
|
|
int Cdrfifo_get_min_fill(struct CdrfifO *o, int *total_min_fill,
|
||
|
|
int *interval_min_fill, int flag);
|
||
|
|
|
||
|
|
int Cdrfifo_get_cdr_counters(struct CdrfifO *o,
|
||
|
|
double *put_counter, double *get_counter,
|
||
|
|
double *empty_counter, double *full_counter,
|
||
|
|
int flag);
|
||
|
|
|
||
|
|
/** Inquire the eventually detected size of an eventual ISO-9660 file system
|
||
|
|
@return 0=no ISO resp. size detected, 1=size_in_bytes is valid
|
||
|
|
*/
|
||
|
|
int Cdrfifo_get_iso_fs_size(struct CdrfifO *o, double *size_in_bytes,int flag);
|
||
|
|
|
||
|
|
|
||
|
|
/** Take over the eventually memorized blocks 16 to 31 of input (2 kB each).
|
||
|
|
The fifo forgets the blocks by this call. I.e. a second one will return 0.
|
||
|
|
After this call it is the responsibility of the caller to dispose the
|
||
|
|
retrieved memory via call free().
|
||
|
|
@param pt Will be filled either with NULL or a pointer to 32 kB of data
|
||
|
|
@return 0=nothing is buffered, 1=pt points to valid freeable data
|
||
|
|
*/
|
||
|
|
int Cdrfifo_adopt_iso_fs_descr(struct CdrfifO *o, char **pt, int flag);
|
||
|
|
|
||
|
|
|
||
|
|
/** Check for pending data at the fifo's source file descriptor and wether the
|
||
|
|
fifo is ready to take them. Simultaneously check the buffer for existing
|
||
|
|
data and the destination fd for readiness to accept some. If so, a small
|
||
|
|
chunk of data is transfered to and/or from the fifo.
|
||
|
|
This is done for the given fifo object and all members of its next-chain.
|
||
|
|
The check and transactions are repeated until a given timespan has elapsed.
|
||
|
|
libburn applications call this function in the burn loop instead of sleep().
|
||
|
|
It may also be used instead of read(). Then it returns as soon as an output
|
||
|
|
transaction would be performed. See flag:bit2.
|
||
|
|
@param o The fifo object
|
||
|
|
@param wait_usec The time in microseconds after which the function shall
|
||
|
|
return.
|
||
|
|
@param reply_buffer with bit2: Returns write-ready buffer chunk and must
|
||
|
|
be able to take at least chunk_size bytes
|
||
|
|
@param reply_count with bit2: Returns number of writeable bytes in reply_pt
|
||
|
|
@param flag Bitfield for control purposes:
|
||
|
|
bit0= Enable debug pacifier (same with Cdrfifo_debuG)
|
||
|
|
bit1= Do not write, just fill buffer
|
||
|
|
bit2= fd-to-memory mode (else fd-to-fd mode):
|
||
|
|
Rather than writing a chunk return it and its size.
|
||
|
|
No simultaneous processing of chained fifos.
|
||
|
|
bit3= With bit2: do not check destination fd for readiness
|
||
|
|
@return <0 = error , 0 = idle , 1 = did some work , 2 = all work is done
|
||
|
|
*/
|
||
|
|
int Cdrfifo_try_to_work(struct CdrfifO *o, int wait_usec,
|
||
|
|
char *reply_buffer, int *reply_count, int flag);
|
||
|
|
|
||
|
|
/** Fill the fifo as far as possible without writing to destination fd.
|
||
|
|
@param size if >=0 : end filling after the given number of bytes
|
||
|
|
@return 1 on success, <=0 on failure
|
||
|
|
*/
|
||
|
|
int Cdrfifo_fill(struct CdrfifO *o, int size, int flag);
|
||
|
|
|
||
|
|
|
||
|
|
#endif /* Cdrfifo_headerfile_includeD */
|
||
|
|
|