ebitmap.h 1.6 KB

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  1. /*
  2. * An extensible bitmap is a bitmap that supports an
  3. * arbitrary number of bits. Extensible bitmaps are
  4. * used to represent sets of values, such as types,
  5. * roles, categories, and classes.
  6. *
  7. * Each extensible bitmap is implemented as a linked
  8. * list of bitmap nodes, where each bitmap node has
  9. * an explicitly specified starting bit position within
  10. * the total bitmap.
  11. *
  12. * Author : Stephen Smalley, <sds@epoch.ncsc.mil>
  13. */
  14. #ifndef _SS_EBITMAP_H_
  15. #define _SS_EBITMAP_H_
  16. #define MAPTYPE u64 /* portion of bitmap in each node */
  17. #define MAPSIZE (sizeof(MAPTYPE) * 8) /* number of bits in node bitmap */
  18. #define MAPBIT 1ULL /* a bit in the node bitmap */
  19. struct ebitmap_node {
  20. u32 startbit; /* starting position in the total bitmap */
  21. MAPTYPE map; /* this node's portion of the bitmap */
  22. struct ebitmap_node *next;
  23. };
  24. struct ebitmap {
  25. struct ebitmap_node *node; /* first node in the bitmap */
  26. u32 highbit; /* highest position in the total bitmap */
  27. };
  28. #define ebitmap_length(e) ((e)->highbit)
  29. #define ebitmap_startbit(e) ((e)->node ? (e)->node->startbit : 0)
  30. static inline void ebitmap_init(struct ebitmap *e)
  31. {
  32. memset(e, 0, sizeof(*e));
  33. }
  34. int ebitmap_cmp(struct ebitmap *e1, struct ebitmap *e2);
  35. int ebitmap_cpy(struct ebitmap *dst, struct ebitmap *src);
  36. int ebitmap_contains(struct ebitmap *e1, struct ebitmap *e2);
  37. int ebitmap_get_bit(struct ebitmap *e, unsigned long bit);
  38. int ebitmap_set_bit(struct ebitmap *e, unsigned long bit, int value);
  39. void ebitmap_destroy(struct ebitmap *e);
  40. int ebitmap_read(struct ebitmap *e, void *fp);
  41. #endif /* _SS_EBITMAP_H_ */