skarg
62 lines
1.7 KiB
C
62 lines
1.7 KiB
C
/*
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+----------------------------------------------------+
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| Thunderbird Software |
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+----------------------------------------------------+
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| Filespec : Queue.c |
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| Date : September 29, 1994 |
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| Time : 10:16AM |
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| Revision : 1.0 |
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+----------------------------------------------------+
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| Programmer: Scott Andrews |
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| Address : 5358 Summit RD SW |
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| City/State: Pataskala, Ohio |
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| Zip : 43062 |
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+----------------------------------------------------+
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| Released to the Public Domain |
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+----------------------------------------------------+
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*/
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#include <stdlib.h>
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#include "queue.h"
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QUEUE *alloc_queue( int size)
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{ QUEUE *retval;
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retval = (QUEUE *) malloc( sizeof( QUEUE) + (size_t) size);
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if ( (QUEUE *) 0 != retval)
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{ retval->size = size;
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retval->head = 0;
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retval->tail = 0;
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retval->avail = size;
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retval->buffer = ( (char *) retval) + sizeof( QUEUE);
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}
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return retval;
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}
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int en_queue( QUEUE *queue, char data)
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{ int retval = -1;
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if ( 0 != queue->avail)
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{ *( queue->buffer + queue->head) = data;
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queue->head += 1;
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if ( queue->head == queue->size)
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queue->head = 0;
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queue->avail -= 1;
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retval = queue->avail;
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}
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return retval;
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}
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int de_queue( QUEUE *queue)
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{ int retval = -1;
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if ( queue->avail != queue->size)
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{ retval = *( queue->buffer + queue->tail);
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queue->tail += 1;
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if ( queue->tail == queue->size)
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queue->tail = 0;
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queue->avail += 1;
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}
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return retval;
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}
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/* End of Queue.c */
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