tomwalters@0: /*
tomwalters@0:     fillable.c
tomwalters@0:     ==========
tomwalters@0: 
tomwalters@0:     Sources whose native mode of operation is the fill entry point.
tomwalters@0:     They may be pulled in which case a buffer is allocated.
tomwalters@0: 
tomwalters@0: */
tomwalters@0: 
tomwalters@0: #include "stitch.h"
tomwalters@0: #include "source.h"
tomwalters@0: 
tomwalters@0: #ifndef  lint
tomwalters@0: static char *sccs_id = "@(#)fillable.c	1.2 John Holdsworth (MRC-APU) 11/8/90" ;
tomwalters@0: #endif
tomwalters@0: 
tomwalters@0: #if 0
tomwalters@0: #define DEBUG 1
tomwalters@0: #endif
tomwalters@0: 
tomwalters@0: Source SharingSource( source1, source2 )
tomwalters@0: struct _fillable_source *source1, *source2 ;
tomwalters@0: {
tomwalters@0:     DeleteBuffer( source1->buffer ) ;
tomwalters@0: 
tomwalters@0:     source1->buffer = SharedBuffer( source2->buffer ) ;
tomwalters@0: 
tomwalters@0:     return ( (Source) source1 ) ;
tomwalters@0: }
tomwalters@0: 
tomwalters@0: /* converter of pull command to fill commands */
tomwalters@0: 
tomwalters@0: static Pointer pullFromFillable( source, bytes )
tomwalters@0: struct _fillable_source *source ;
tomwalters@0: ByteCount *bytes ;
tomwalters@0: {
tomwalters@0: #if DEBUG
tomwalters@0:     printf( "buffering pulling from passive \"%s\", %d bytes\n", SourceName( source ), *bytes ) ;
tomwalters@0: #endif
tomwalters@0: #if 00
tomwalters@0:     if( source->bsize < *bytes ) {
tomwalters@0: 
tomwalters@0: 	if( source->bsize != 0 )
tomwalters@0: 	    Delete( source->buffer ) ;
tomwalters@0: 
tomwalters@0: 	source->buffer = Allocate( *bytes, "fillable.c for source buffer" ) ;
tomwalters@0: 
tomwalters@0: 	source->bsize  = *bytes ;
tomwalters@0:     }
tomwalters@0: #endif
tomwalters@0:     return ( source->parent.fill( source, bytes, SizedBufferPointer( SourceBuffer( source ), *bytes ) ) ) ;
tomwalters@0: }
tomwalters@0: 
tomwalters@0: /* constructor for all pullable sources */
tomwalters@0: 
tomwalters@0: Source setFillableSource( source, filler, name )
tomwalters@0: struct _fillable_source *source ;
tomwalters@0: Pointer (*filler)() ;
tomwalters@0: char *name ;
tomwalters@0: {
tomwalters@0:     source->buffer = NewBuffer( "pulling" ) ;
tomwalters@0: 
tomwalters@0:     return ( SetSource( source, pullFromFillable, filler, nonRoller, name ) ) ;
tomwalters@0: }
tomwalters@0: 
tomwalters@0: Pointer deleteFillableSource( source )
tomwalters@0: struct _fillable_source *source ;
tomwalters@0: {
tomwalters@0:     DeleteBuffer( source->buffer ) ;
tomwalters@0: 
tomwalters@0:     return ( DeleteSource( source ) ) ;
tomwalters@0: }
tomwalters@0: 
tomwalters@0: 
tomwalters@0: /* derived fillable source */
tomwalters@0: 
tomwalters@0: typedef struct {
tomwalters@0:  struct _fillable_source parent ;
tomwalters@0:  Pointer data, end, ptr ;
tomwalters@0:  } *RepeatingSource ;
tomwalters@0: 
tomwalters@0: static Pointer repeating_callback( source, bytes, buffer )
tomwalters@0: RepeatingSource source ;
tomwalters@0: ByteCount *bytes ;
tomwalters@0: Pointer buffer ;
tomwalters@0: {
tomwalters@0:     register int last = *bytes == 0 ;
tomwalters@0:     register Pointer bptr = buffer ;
tomwalters@0:     register Pointer bend = buffer + *bytes ;
tomwalters@0:     register ByteCount segment ;
tomwalters@0: 
tomwalters@0:     if( !last ) {
tomwalters@0: 
tomwalters@0: 	while( bptr < bend ) {
tomwalters@0: 
tomwalters@0: 	    segment = source->end - source->ptr ;
tomwalters@0: 	    if( segment > bend - bptr )
tomwalters@0: 		segment = bend - bptr ;
tomwalters@0: 
tomwalters@0: 	    CopyArray( (char *) source->ptr, (char *) bptr, segment ) ;
tomwalters@0: 
tomwalters@0: 	    source->ptr += segment ;
tomwalters@0: 	    bptr        += segment ;
tomwalters@0: 
tomwalters@0: 	    if( source->ptr == source->end )
tomwalters@0: 		source->ptr = source->data ;
tomwalters@0: 	}
tomwalters@0: 
tomwalters@0: 	return ( buffer ) ;
tomwalters@0:     }
tomwalters@0:     else
tomwalters@0: 	return ( DeleteFillableSource( source ) ) ;
tomwalters@0: }
tomwalters@0: 
tomwalters@0: Source newRepeatingSource( data, segment )
tomwalters@0: Pointer data ;
tomwalters@0: ByteCount segment ;
tomwalters@0: {
tomwalters@0:     DeclareNew( RepeatingSource, source ) ;
tomwalters@0: 
tomwalters@0:     source->data = data ;
tomwalters@0:     source->end  = data + segment ;
tomwalters@0: 
tomwalters@0:     source->ptr  = source->data ;
tomwalters@0: 
tomwalters@0:     return ( SetFillableSource( source, repeating_callback, "fillable.c repeating" ) ) ;
tomwalters@0: }
tomwalters@0: 
tomwalters@0: typedef struct {
tomwalters@0:  struct _fillable_source parent ;
tomwalters@0:  Source input ; ByteCount segment ;
tomwalters@0:  } *SegmentingSource ;
tomwalters@0: 
tomwalters@0: static Pointer segmenting_callback( source, bytes, buffer )
tomwalters@0: SegmentingSource source ;
tomwalters@0: ByteCount *bytes ;
tomwalters@0: Pointer buffer ;
tomwalters@0: {
tomwalters@0:     register int last = *bytes == 0 ;
tomwalters@0:     Pointer bptr = buffer ;
tomwalters@0:     ByteCount segment ;
tomwalters@0: 
tomwalters@0:     do {
tomwalters@0: 
tomwalters@0: 	segment = source->segment ;
tomwalters@0: 
tomwalters@0: 	if( segment > buffer + *bytes - bptr )
tomwalters@0: 	    segment = buffer + *bytes - bptr ;
tomwalters@0: 
tomwalters@0: 	(void) FillSome( source->input, &segment, bptr ) ;
tomwalters@0: 
tomwalters@0: 	bptr += segment ;
tomwalters@0: 
tomwalters@0:     } while ( bptr < buffer + *bytes ) ;
tomwalters@0: 
tomwalters@0:     if( !last )
tomwalters@0: 	return ( buffer  ) ;
tomwalters@0:     else
tomwalters@0: 	return ( DeleteFillableSource( source ) ) ;
tomwalters@0: }
tomwalters@0: 
tomwalters@0: Source newSegmentingSource( input, segment )
tomwalters@0: Source input ;
tomwalters@0: ByteCount segment ;
tomwalters@0: {
tomwalters@0:     DeclareNew( SegmentingSource, source ) ;
tomwalters@0: 
tomwalters@0:     source->input = input ;
tomwalters@0: 
tomwalters@0:     source->segment = segment ;
tomwalters@0: 
tomwalters@0:     return ( SetFillableSource( source, segmenting_callback, "segmenting" ) ) ;
tomwalters@0: }
tomwalters@0: 
tomwalters@0: 
tomwalters@0: 
tomwalters@0: /* higher level methods to sources */
tomwalters@0: 
tomwalters@0: 
tomwalters@0: typedef struct _callback_source {
tomwalters@0:  struct _fillable_source parent ;
tomwalters@0:  Pointer state ;
tomwalters@0:  void (*callback)(), (*close)() ;
tomwalters@0:  } *CallbackSource ;
tomwalters@0: 
tomwalters@0: Source setCallbackSource( source, filler, state, callback, close, name )
tomwalters@0: CallbackSource source ;
tomwalters@0: Pointer (*filler)() ;
tomwalters@0: Pointer state ;
tomwalters@0: void (*callback)(), (*close)() ;
tomwalters@0: char *name ;
tomwalters@0: {
tomwalters@0:     source->state    = state    ;
tomwalters@0:     source->callback = callback ;
tomwalters@0:     source->close    = close    ;
tomwalters@0: 
tomwalters@0:     return ( SetFillableSource( source, filler, name ) ) ;
tomwalters@0: }
tomwalters@0: 
tomwalters@0: Source newCallbackSource( filler, state, callback, close, name )
tomwalters@0: Pointer (*filler)() ;
tomwalters@0: Pointer state ;
tomwalters@0: void (*callback)(), (*close)() ;
tomwalters@0: char *name ;
tomwalters@0: {
tomwalters@0:     return ( setCallbackSource( New( CallbackSource ), filler, state, callback, close, name ) ) ;
tomwalters@0: }
tomwalters@0: 
tomwalters@0: static Pointer externalFiller( source, bytes, buffer )
tomwalters@0: CallbackSource source ;
tomwalters@0: ByteCount *bytes ;
tomwalters@0: Pointer buffer ;
tomwalters@0: {
tomwalters@0:     register int last = *bytes == 0 ;
tomwalters@0: 
tomwalters@0:     source->callback( source->state, bytes, buffer, buffer+*bytes ) ;
tomwalters@0: 
tomwalters@0:     if( !last )
tomwalters@0: 	return ( buffer ) ;
tomwalters@0:     else {
tomwalters@0: 	if( source->close != (void ( * )()) 0 )
tomwalters@0: 	    source->close( source->state ) ;
tomwalters@0: 
tomwalters@0: 	return ( DeleteFillableSource( source ) ) ;
tomwalters@0:     }
tomwalters@0: }
tomwalters@0: 
tomwalters@0: Source newExternalSource( state, callback, close, name )
tomwalters@0: Pointer state ;
tomwalters@0: void (*callback)(), (*close)() ;
tomwalters@0: char *name ;
tomwalters@0: {
tomwalters@0:     return ( newCallbackSource( externalFiller, state, callback, close, name ) ) ;
tomwalters@0: }
tomwalters@0: 
tomwalters@0: typedef struct _through_source {
tomwalters@0:  struct _callback_source parent ;
tomwalters@0:  Source input ;
tomwalters@0:  } *ThroughSource ;
tomwalters@0: 
tomwalters@0: static Source setThroughSource( source, filler, state, callback, close, input, name )
tomwalters@0: ThroughSource source ;
tomwalters@0: Pointer (*filler)() ;
tomwalters@0: Pointer state ;
tomwalters@0: void (*callback)(), (*close)() ;
tomwalters@0: Source input ;
tomwalters@0: char *name ;
tomwalters@0: {
tomwalters@0:     source->input = input ;
tomwalters@0: 
tomwalters@0:     return ( setCallbackSource( (CallbackSource) source, filler, state, callback, close, name ) ) ;
tomwalters@0: }
tomwalters@0: 
tomwalters@0: Source newThroughSource( filler, state, callback, close, input, name )
tomwalters@0: Pointer (*filler)(), state ;
tomwalters@0: void (*callback)(), (*close)() ;
tomwalters@0: Source input ;
tomwalters@0: char *name ;
tomwalters@0: {
tomwalters@0:     return ( setThroughSource( New( ThroughSource ), filler, state, callback, close, input, name ) ) ;
tomwalters@0: }
tomwalters@0: 
tomwalters@0: 
tomwalters@0: static Pointer processingFiller( source, bytes, buffer )
tomwalters@0: ThroughSource source ;
tomwalters@0: ByteCount *bytes ;
tomwalters@0: Pointer buffer ;
tomwalters@0: {
tomwalters@0:     register int last = *bytes == 0 ;
tomwalters@0: 
tomwalters@0:     source->parent.callback( source->parent.state, bytes, buffer, buffer+*bytes, PullSome( source->input, bytes ) ) ;
tomwalters@0: 
tomwalters@0:     if( !last )
tomwalters@0: 	return ( buffer ) ;
tomwalters@0:     else {
tomwalters@0: 	if( source->parent.close != (void ( * )()) 0 )
tomwalters@0: 	    source->parent.close( source->parent.state ) ;
tomwalters@0: 
tomwalters@0: 	return ( DeleteFillableSource( &source->parent ) ) ;
tomwalters@0:     }
tomwalters@0: }
tomwalters@0: 
tomwalters@0: Source newProcessingSource( state, callback, close, input, name )
tomwalters@0: Pointer state ;
tomwalters@0: void (*callback)(), (*close)() ;
tomwalters@0: Source input ;
tomwalters@0: char *name ;
tomwalters@0: {
tomwalters@0:     return ( newThroughSource( processingFiller, state, callback, close, input, name ) ) ;
tomwalters@0: }
tomwalters@0: 
tomwalters@0: Source newSimpleProcessingSource( callback, input, name )
tomwalters@0: void (*callback)() ;
tomwalters@0: Source input ;
tomwalters@0: char *name ;
tomwalters@0: {
tomwalters@0:     return ( NewProcessingSource( (Pointer) 0, callback, (void ( * )()) 0, input, name ) ) ;
tomwalters@0: }
tomwalters@0: 
tomwalters@0: typedef struct {
tomwalters@0:     struct _fillable_source parent ;
tomwalters@0:     Pointer *states ;
tomwalters@0:     int (*callback)() ;
tomwalters@0:     void (*close)() ;
tomwalters@0:     int channels ;
tomwalters@0:     Source input ;
tomwalters@0: } *MultiplexedSource ;
tomwalters@0: 
tomwalters@0: static Pointer multiplexed_callback( source, bytes, buffer )
tomwalters@0: MultiplexedSource source ;
tomwalters@0: ByteCount *bytes ;
tomwalters@0: Pointer buffer ;
tomwalters@0: {
tomwalters@0:     register int last = *bytes == 0 ;
tomwalters@0:     Pointer iptr = PullSome( source->input, bytes ) ;
tomwalters@0:     Pointer optr = buffer ;
tomwalters@0:     Pointer end = buffer + *bytes ;
tomwalters@0:     ByteCount data_size ;
tomwalters@0:     int channel ;
tomwalters@0: 
tomwalters@0:     for( channel=0 ; channel<source->channels ; channel++ ) {
tomwalters@0: 	data_size = source->callback( source->states[channel], optr, end, iptr, source->channels ) ;
tomwalters@0: 	iptr += data_size ;
tomwalters@0: 	optr += data_size ;
tomwalters@0:     }
tomwalters@0: 
tomwalters@0:     if( !last )
tomwalters@0: 	return ( buffer ) ;
tomwalters@0:     else {
tomwalters@0: 	if( source->close != (void ( * )()) 0 )
tomwalters@0: 	    for( channel=0 ; channel<source->channels ; channel++ )
tomwalters@0: 		source->close( source->states[channel] ) ;
tomwalters@0: 
tomwalters@0: 	Delete( source->states ) ;
tomwalters@0: 
tomwalters@0: 	return ( DeleteFillableSource( source ) ) ;
tomwalters@0:     }
tomwalters@0: }
tomwalters@0: 
tomwalters@0: Source newMultiplexedSource( states, callback, close, channels, input, name )
tomwalters@0: Pointer *states ;
tomwalters@0: int (*callback)() ;
tomwalters@0: void (*close)() ;
tomwalters@0: int channels ;
tomwalters@0: Source input ;
tomwalters@0: char *name ;
tomwalters@0: {
tomwalters@0:     DeclareNew( MultiplexedSource, source ) ;
tomwalters@0: 
tomwalters@0:     source->states   = states   ;
tomwalters@0:     source->callback = callback ;
tomwalters@0:     source->close    = close    ;
tomwalters@0:     source->channels = channels ;
tomwalters@0: 
tomwalters@0:     source->input    = input    ;
tomwalters@0: 
tomwalters@0:     return ( SetFillableSource( source, multiplexed_callback, name ) ) ;
tomwalters@0: }
tomwalters@0: 
tomwalters@0: typedef struct _merging_source {
tomwalters@0:  struct _callback_source parent ; Source *inputs ;
tomwalters@0:  } *MergingSource ;
tomwalters@0: 
tomwalters@0: static Pointer mergingFiller( source, bytes, buffer )
tomwalters@0: MergingSource source ;
tomwalters@0: ByteCount *bytes ;
tomwalters@0: Pointer buffer ;
tomwalters@0: {
tomwalters@0:     register int last = *bytes == 0 ;
tomwalters@0:     Pointer input1, input2 ;
tomwalters@0:     int n ;
tomwalters@0: 
tomwalters@0:     input1 = PullSome( source->inputs[0], bytes ) ;
tomwalters@0: 
tomwalters@0:     for( n=1 ; _SPTR( source->inputs[n] ) != (struct _source *) 0 ; n++ ) {
tomwalters@0: 
tomwalters@0: 	input2 = PullSome( source->inputs[n], bytes ) ;
tomwalters@0: 
tomwalters@0: 	source->parent.callback( source->parent.state, bytes, buffer, buffer+*bytes, input1, input2 ) ;
tomwalters@0: 
tomwalters@0: 	input1 = buffer ;
tomwalters@0:     }
tomwalters@0: 
tomwalters@0:     if( !last )
tomwalters@0: 	return ( buffer ) ;
tomwalters@0:     else {
tomwalters@0: 	Delete( source->inputs  ) ;
tomwalters@0: 
tomwalters@0: 	return ( DeleteFillableSource( &source->parent ) ) ;
tomwalters@0:     }
tomwalters@0: }
tomwalters@0: 
tomwalters@0: Source newMergingSource( state, callback, close, inputs, name )
tomwalters@0: Pointer state ;
tomwalters@0: void (*callback)(), (*close)() ;
tomwalters@0: Source *inputs ;
tomwalters@0: char *name ;
tomwalters@0: {
tomwalters@0:     DeclareNew( MergingSource, source ) ;
tomwalters@0: 
tomwalters@0:     source->inputs = inputs ;
tomwalters@0: 
tomwalters@0:     return ( setCallbackSource( (CallbackSource) source, mergingFiller, state, callback, close, name ) ) ;
tomwalters@0: }
tomwalters@0: