/
githubmirror
/
postgres
Обзор
Документация
Войти
/
githubmirror
/
postgres
Код
Запросы
0
Пакеты
0
Релизы
0
Аналитика
Безопасность
master
src/include/nodes/bitmapset.h
141 строка
5 KB
David Rowley
Introduce bms_offset_members() function
08 июл 2026, 16:11
08 июл 2026, 16:11
bb7ded1
Код
Авторство
О чём код?
/*------------------------------------------------------------------------- * * 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, we always represent the * empty set by a NULL pointer. * * * Copyright (c) 2003-2026, PostgreSQL Global Development Group * * src/include/nodes/bitmapset.h * *------------------------------------------------------------------------- */ #ifndef BITMAPSET_H #define BITMAPSET_H #include "nodes/nodes.h" /* * Forward decl to save including pg_list.h */ struct List; /* * Data representation * * Larger bitmap word sizes generally give better performance, so long as * they're not wider than the processor can handle efficiently. We use * 64-bit words if pointers are that large, else 32-bit words. */ #if SIZEOF_VOID_P >= 8 #define BITS_PER_BITMAPWORD 64 typedef uint64 bitmapword; /* must be an unsigned type */ typedef int64 signedbitmapword; /* must be the matching signed type */ #else #define BITS_PER_BITMAPWORD 32 typedef uint32 bitmapword; /* must be an unsigned type */ typedef int32 signedbitmapword; /* must be the matching signed type */ #endif typedef struct Bitmapset { pg_node_attr(custom_copy_equal, special_read_write, no_query_jumble) NodeTag type; int nwords; /* number of words in array */ bitmapword words[FLEXIBLE_ARRAY_MEMBER]; /* really [nwords] */ } Bitmapset; /* result of bms_subset_compare */ typedef enum { BMS_EQUAL, /* sets are equal */ BMS_SUBSET1, /* first set is a subset of the second */ BMS_SUBSET2, /* second set is a subset of the first */ BMS_DIFFERENT, /* neither set is a subset of the other */ } BMS_Comparison; /* result of bms_membership */ typedef enum { BMS_EMPTY_SET, /* 0 members */ BMS_SINGLETON, /* 1 member */ BMS_MULTIPLE, /* >1 member */ } BMS_Membership; /* Select appropriate bit-twiddling functions for bitmap word size */ #if BITS_PER_BITMAPWORD == 32 #define bmw_leftmost_one_pos(w) pg_leftmost_one_pos32(w) #define bmw_rightmost_one_pos(w) pg_rightmost_one_pos32(w) #define bmw_popcount(w) pg_popcount32(w) #elif BITS_PER_BITMAPWORD == 64 #define bmw_leftmost_one_pos(w) pg_leftmost_one_pos64(w) #define bmw_rightmost_one_pos(w) pg_rightmost_one_pos64(w) #define bmw_popcount(w) pg_popcount64(w) #else #error "invalid BITS_PER_BITMAPWORD" #endif /* * 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 Bitmapset *bms_offset_members(const Bitmapset *a, int offset); extern bool bms_is_subset(const Bitmapset *a, const Bitmapset *b); extern BMS_Comparison bms_subset_compare(const Bitmapset *a, const Bitmapset *b); extern bool bms_is_member(int x, const Bitmapset *a); extern int bms_member_index(Bitmapset *a, int x); extern bool bms_overlap(const Bitmapset *a, const Bitmapset *b); extern bool bms_overlap_list(const Bitmapset *a, const struct List *b); extern bool bms_nonempty_difference(const Bitmapset *a, const Bitmapset *b); extern int bms_singleton_member(const Bitmapset *a); extern bool bms_get_singleton_member(const Bitmapset *a, int *member); 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); /* NULL is now the only allowed representation of an empty bitmapset */ #define bms_is_empty(a) ((a) == NULL) /* these routines recycle (modify or free) their non-const inputs: */ 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_replace_members(Bitmapset *a, const Bitmapset *b); extern Bitmapset *bms_add_range(Bitmapset *a, int lower, int upper); 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_next_member(const Bitmapset *a, int prevbit); extern int bms_prev_member(const Bitmapset *a, int prevbit); /* support for hashtables using Bitmapsets as keys: */ extern uint32 bms_hash_value(const Bitmapset *a); extern uint32 bitmap_hash(const void *key, Size keysize); extern int bitmap_match(const void *key1, const void *key2, Size keysize); #endif /* BITMAPSET_H */