| /*------------------------------------------------------------------------- |
| * |
| * bitmapset.h |
| * PostgreSQL generic bitmap set package |
| * |
| * A bitmap set can represent any set of nonnegative integers, although |
| * it is mainly intended for sets where the maximum value is not large, |
| * say at most a few hundred. By convention, a NULL pointer is always |
| * accepted by all operations to represent the empty set. (But beware |
| * that this is not the only representation of the empty set. Use |
| * bms_is_empty() in preference to testing for NULL.) |
| * |
| * |
| * Copyright (c) 2003-2009, PostgreSQL Global Development Group |
| * |
| * $PostgreSQL: pgsql/src/include/nodes/bitmapset.h,v 1.8 2006/03/05 15:58:56 momjian Exp $ |
| * |
| *------------------------------------------------------------------------- |
| */ |
| #ifndef BITMAPSET_H |
| #define BITMAPSET_H |
| |
| /* |
| * Data representation |
| */ |
| |
| /* The unit size can be adjusted by changing these three declarations: */ |
| #define BITS_PER_BITMAPWORD 32 |
| typedef uint32 bitmapword; /* must be an unsigned type */ |
| typedef int32 signedbitmapword; /* must be the matching signed type */ |
| #define BITS_PER_BITMAPWORD_LOG2 5 |
| |
| typedef struct Bitmapset |
| { |
| int nwords; /* number of words in array */ |
| bitmapword words[1]; /* really [nwords] */ |
| } Bitmapset; /* VARIABLE LENGTH STRUCT */ |
| |
| |
| /* result of bms_membership */ |
| typedef enum |
| { |
| BMS_EMPTY_SET, /* 0 members */ |
| BMS_SINGLETON, /* 1 member */ |
| BMS_MULTIPLE /* >1 member */ |
| } BMS_Membership; |
| |
| |
| /* |
| * function prototypes in nodes/bitmapset.c |
| */ |
| |
| extern Bitmapset *bms_copy(const Bitmapset *a); |
| extern bool bms_equal(const Bitmapset *a, const Bitmapset *b); |
| extern int bms_compare(const Bitmapset *a, const Bitmapset *b); |
| extern Bitmapset *bms_make_singleton(int x); |
| extern void bms_free(Bitmapset *a); |
| |
| extern Bitmapset *bms_union(const Bitmapset *a, const Bitmapset *b); |
| extern Bitmapset *bms_intersect(const Bitmapset *a, const Bitmapset *b); |
| extern Bitmapset *bms_difference(const Bitmapset *a, const Bitmapset *b); |
| extern bool bms_is_subset(const Bitmapset *a, const Bitmapset *b); |
| extern bool bms_is_member(int x, const Bitmapset *a); |
| extern bool bms_overlap(const Bitmapset *a, const Bitmapset *b); |
| extern bool bms_nonempty_difference(const Bitmapset *a, const Bitmapset *b); |
| extern int bms_singleton_member(const Bitmapset *a); |
| extern int bms_num_members(const Bitmapset *a); |
| |
| /* optimized tests when we don't need to know exact membership count: */ |
| extern BMS_Membership bms_membership(const Bitmapset *a); |
| extern bool bms_is_empty(const Bitmapset *a); |
| |
| /* these routines recycle (modify or free) their non-const inputs: */ |
| |
| extern Bitmapset *bms_assign(Bitmapset *tgt, const Bitmapset *src); |
| extern Bitmapset *bms_add_member(Bitmapset *a, int x); |
| extern Bitmapset *bms_del_member(Bitmapset *a, int x); |
| extern Bitmapset *bms_add_members(Bitmapset *a, const Bitmapset *b); |
| extern Bitmapset *bms_int_members(Bitmapset *a, const Bitmapset *b); |
| extern Bitmapset *bms_del_members(Bitmapset *a, const Bitmapset *b); |
| extern Bitmapset *bms_join(Bitmapset *a, Bitmapset *b); |
| |
| /* support for iterating through the integer elements of a set: */ |
| extern int bms_first_from(const Bitmapset *a, int x); |
| |
| #define bms_foreach(_member, _set) \ |
| for ((_member) = bms_first_from((_set), 0); \ |
| (_member) >= 0; \ |
| (_member) = bms_first_from((_set), (_member)+1)) |
| |
| /* return first member and delete it from the set */ |
| extern int bms_first_member(Bitmapset *a); |
| |
| /* support for hashtables using Bitmapsets as keys: */ |
| extern uint32 bms_hash_value(const Bitmapset *a); |
| |
| #endif /* BITMAPSET_H */ |