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#ifndef _GPXE_BITMAP_H
#define _GPXE_BITMAP_H
/** @file
*
* Bitmaps for multicast downloads
*
*/
FILE_LICENCE ( GPL2_OR_LATER );
#include <stdint.h>
#include <stddef.h>
#include <stdlib.h>
/** A single block of bits within a bitmap */
typedef unsigned long bitmap_block_t;
/** Size of a block of bits (in bits) */
#define BITMAP_BLKSIZE ( sizeof ( bitmap_block_t ) * 8 )
/**
* Block index within bitmap
*
* @v bit Bit index
* @ret index Block index
*/
#define BITMAP_INDEX( bit ) ( (bit) / BITMAP_BLKSIZE )
/**
* Block mask within bitmap
*
* @v bit Bit index
* @ret mask Block mask
*/
#define BITMAP_MASK( bit ) ( 1 << ( (bit) % BITMAP_BLKSIZE ) )
/** A bitmap */
struct bitmap {
/** Bitmap data */
bitmap_block_t *blocks;
/** Length of the bitmap, in bits */
unsigned int length;
/** Index of first gap in the bitmap */
unsigned int first_gap;
};
extern int bitmap_resize ( struct bitmap *bitmap, unsigned int new_length );
extern int bitmap_test ( struct bitmap *bitmap, unsigned int bit );
extern void bitmap_set ( struct bitmap *bitmap, unsigned int bit );
/**
* Free bitmap resources
*
* @v bitmap Bitmap
*/
static inline void bitmap_free ( struct bitmap *bitmap ) {
free ( bitmap->blocks );
}
/**
* Get first gap within bitmap
*
* @v bitmap Bitmap
* @ret first_gap First gap
*
* The first gap is the first unset bit within the bitmap.
*/
static inline unsigned int bitmap_first_gap ( struct bitmap *bitmap ) {
return bitmap->first_gap;
}
/**
* Check to see if bitmap is full
*
* @v bitmap Bitmap
* @ret is_full Bitmap is full
*
* The bitmap is full if it has no gaps (i.e. no unset bits).
*/
static inline int bitmap_full ( struct bitmap *bitmap ) {
return ( bitmap->first_gap == bitmap->length );
}
#endif /* _GPXE_BITMAP_H */
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