1 /* Author : Stephen Smalley, <sds@epoch.ncsc.mil> */
2 
3 /* FLASK */
4 
5 /*
6  * An extensible bitmap is a bitmap that supports an
7  * arbitrary number of bits.  Extensible bitmaps are
8  * used to represent sets of values, such as types,
9  * roles, categories, and classes.
10  *
11  * Each extensible bitmap is implemented as a linked
12  * list of bitmap nodes, where each bitmap node has
13  * an explicitly specified starting bit position within
14  * the total bitmap.
15  */
16 
17 #ifndef _SEPOL_POLICYDB_EBITMAP_H_
18 #define _SEPOL_POLICYDB_EBITMAP_H_
19 
20 #include <stdint.h>
21 #include <string.h>
22 #include <sys/cdefs.h>
23 
24 __BEGIN_DECLS
25 
26 #define MAPTYPE uint64_t	/* portion of bitmap in each node */
27 #define MAPSIZE (sizeof(MAPTYPE) * 8)	/* number of bits in node bitmap */
28 #define MAPBIT  1ULL		/* a bit in the node bitmap */
29 
30 typedef struct ebitmap_node {
31 	uint32_t startbit;	/* starting position in the total bitmap */
32 	MAPTYPE map;		/* this node's portion of the bitmap */
33 	struct ebitmap_node *next;
34 } ebitmap_node_t;
35 
36 typedef struct ebitmap {
37 	ebitmap_node_t *node;	/* first node in the bitmap */
38 	uint32_t highbit;	/* highest position in the total bitmap */
39 } ebitmap_t;
40 
41 #define ebitmap_length(e) ((e)->highbit)
42 #define ebitmap_startbit(e) ((e)->node ? (e)->node->startbit : 0)
43 #define ebitmap_startnode(e) ((e)->node)
44 
ebitmap_start(const ebitmap_t * e,ebitmap_node_t ** n)45 static inline unsigned int ebitmap_start(const ebitmap_t * e,
46 					 ebitmap_node_t ** n)
47 {
48 
49 	*n = e->node;
50 	return ebitmap_startbit(e);
51 }
52 
ebitmap_init(ebitmap_t * e)53 static inline void ebitmap_init(ebitmap_t * e)
54 {
55 	memset(e, 0, sizeof(*e));
56 }
57 
ebitmap_next(ebitmap_node_t ** n,unsigned int bit)58 static inline unsigned int ebitmap_next(ebitmap_node_t ** n, unsigned int bit)
59 {
60 	if ((bit == ((*n)->startbit + MAPSIZE - 1)) && (*n)->next) {
61 		*n = (*n)->next;
62 		return (*n)->startbit;
63 	}
64 
65 	return (bit + 1);
66 }
67 
ebitmap_node_get_bit(ebitmap_node_t * n,unsigned int bit)68 static inline int ebitmap_node_get_bit(ebitmap_node_t * n, unsigned int bit)
69 {
70 	if (n->map & (MAPBIT << (bit - n->startbit)))
71 		return 1;
72 	return 0;
73 }
74 
75 #define ebitmap_for_each_bit(e, n, bit) \
76 	for (bit = ebitmap_start(e, &n); bit < ebitmap_length(e); bit = ebitmap_next(&n, bit)) \
77 
78 extern int ebitmap_cmp(const ebitmap_t * e1, const ebitmap_t * e2);
79 extern int ebitmap_or(ebitmap_t * dst, const ebitmap_t * e1, const ebitmap_t * e2);
80 extern int ebitmap_union(ebitmap_t * dst, const ebitmap_t * e1);
81 extern int ebitmap_and(ebitmap_t *dst, ebitmap_t *e1, ebitmap_t *e2);
82 extern int ebitmap_xor(ebitmap_t *dst, ebitmap_t *e1, ebitmap_t *e2);
83 extern int ebitmap_not(ebitmap_t *dst, ebitmap_t *e1, unsigned int maxbit);
84 extern int ebitmap_andnot(ebitmap_t *dst, ebitmap_t *e1, ebitmap_t *e2, unsigned int maxbit);
85 extern unsigned int ebitmap_cardinality(ebitmap_t *e1);
86 extern int ebitmap_hamming_distance(ebitmap_t * e1, ebitmap_t * e2);
87 extern int ebitmap_cpy(ebitmap_t * dst, const ebitmap_t * src);
88 extern int ebitmap_contains(const ebitmap_t * e1, const ebitmap_t * e2);
89 extern int ebitmap_get_bit(const ebitmap_t * e, unsigned int bit);
90 extern int ebitmap_set_bit(ebitmap_t * e, unsigned int bit, int value);
91 extern void ebitmap_destroy(ebitmap_t * e);
92 extern int ebitmap_read(ebitmap_t * e, void *fp);
93 
94 __END_DECLS
95 #endif				/* _EBITMAP_H_ */
96 
97 /* FLASK */
98