Fix xslt_process() to ensure that it inserts a NULL terminator after the
[PostgreSQL.git] / src / include / nodes / bitmapset.h
blobb2e3ae855f884533690804c7ba90938d469a03db
1 /*-------------------------------------------------------------------------
3 * bitmapset.h
4 * PostgreSQL generic bitmap set package
6 * A bitmap set can represent any set of nonnegative integers, although
7 * it is mainly intended for sets where the maximum value is not large,
8 * say at most a few hundred. By convention, a NULL pointer is always
9 * accepted by all operations to represent the empty set. (But beware
10 * that this is not the only representation of the empty set. Use
11 * bms_is_empty() in preference to testing for NULL.)
14 * Copyright (c) 2003-2009, PostgreSQL Global Development Group
16 * $PostgreSQL$
18 *-------------------------------------------------------------------------
20 #ifndef BITMAPSET_H
21 #define BITMAPSET_H
24 * Data representation
27 /* The unit size can be adjusted by changing these three declarations: */
28 #define BITS_PER_BITMAPWORD 32
29 typedef uint32 bitmapword; /* must be an unsigned type */
30 typedef int32 signedbitmapword; /* must be the matching signed type */
32 typedef struct Bitmapset
34 int nwords; /* number of words in array */
35 bitmapword words[1]; /* really [nwords] */
36 } Bitmapset; /* VARIABLE LENGTH STRUCT */
39 /* result of bms_membership */
40 typedef enum
42 BMS_EMPTY_SET, /* 0 members */
43 BMS_SINGLETON, /* 1 member */
44 BMS_MULTIPLE /* >1 member */
45 } BMS_Membership;
49 * function prototypes in nodes/bitmapset.c
52 extern Bitmapset *bms_copy(const Bitmapset *a);
53 extern bool bms_equal(const Bitmapset *a, const Bitmapset *b);
54 extern Bitmapset *bms_make_singleton(int x);
55 extern void bms_free(Bitmapset *a);
57 extern Bitmapset *bms_union(const Bitmapset *a, const Bitmapset *b);
58 extern Bitmapset *bms_intersect(const Bitmapset *a, const Bitmapset *b);
59 extern Bitmapset *bms_difference(const Bitmapset *a, const Bitmapset *b);
60 extern bool bms_is_subset(const Bitmapset *a, const Bitmapset *b);
61 extern bool bms_is_member(int x, const Bitmapset *a);
62 extern bool bms_overlap(const Bitmapset *a, const Bitmapset *b);
63 extern bool bms_nonempty_difference(const Bitmapset *a, const Bitmapset *b);
64 extern int bms_singleton_member(const Bitmapset *a);
65 extern int bms_num_members(const Bitmapset *a);
67 /* optimized tests when we don't need to know exact membership count: */
68 extern BMS_Membership bms_membership(const Bitmapset *a);
69 extern bool bms_is_empty(const Bitmapset *a);
71 /* these routines recycle (modify or free) their non-const inputs: */
73 extern Bitmapset *bms_add_member(Bitmapset *a, int x);
74 extern Bitmapset *bms_del_member(Bitmapset *a, int x);
75 extern Bitmapset *bms_add_members(Bitmapset *a, const Bitmapset *b);
76 extern Bitmapset *bms_int_members(Bitmapset *a, const Bitmapset *b);
77 extern Bitmapset *bms_del_members(Bitmapset *a, const Bitmapset *b);
78 extern Bitmapset *bms_join(Bitmapset *a, Bitmapset *b);
80 /* support for iterating through the integer elements of a set: */
81 extern int bms_first_member(Bitmapset *a);
83 /* support for hashtables using Bitmapsets as keys: */
84 extern uint32 bms_hash_value(const Bitmapset *a);
86 #endif /* BITMAPSET_H */